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CCR Focus Archive
Immunotherapy: Facts and Hopes
Cancer Therapy: Preclinical
Effects of Anti-VEGF Treatment Duration on Tumor Growth, Tumor Regrowth, and Treatment Efficacy
Anil Bagri, Leanne Berry, Bert Gunter, Mallika Singh, Ian Kasman, Lisa A. Damico, Hong Xiang, Maike Schmidt, Germaine Fuh, Beth Hollister, Oliver Rosen and Greg D. Plowman
Anil Bagri
Leanne Berry
Bert Gunter
Mallika Singh
Ian Kasman
Lisa A. Damico
Hong Xiang
Maike Schmidt
Germaine Fuh
Beth Hollister
Oliver Rosen
Greg D. Plowman
DOI: 10.1158/1078-0432.CCR-09-3100 Published August 2010
Purpose: Inhibition of the vascular endothelial growth factor (VEGF) axis is the basis of all currently approved antiangiogenic therapies. In preclinical models, anti-VEGF blocking antibodies have shown broad efficacy that is dependent on both tumor context and treatment duration. We aimed to characterize this activity and to evaluate the effects of discontinuation of treatment on the dynamics of tumor regrowth.
Experimental Design: We evaluated the effects of anti-VEGF treatment on tumor growth and survival in 30 xenograft models and in genetic mouse models of cancer. Histologic analysis was used to evaluate the effects of treatment on tumor vasculature. We used a variety of treatment regimens to allow analysis of the effects of treatment duration and cessation on growth rate, survival, and vascular density.
Results: Preclinical tumor models were characterized for their varied dependence on VEGF, thereby defining models for testing other agents that may complement or augment anti-VEGF therapy. We also found that longer exposure to anti-VEGF monoclonal antibodies delayed tumor growth and extended survival in established tumors from both cell transplants and genetic tumor models and prevented regrowth of a subset of residual tumors following cytoablative therapy. Discontinuation of anti-VEGF in established tumors resulted in regrowth at a rate slower than that in control-treated animals, with no evidence of accelerated tumor growth or rebound. However, more rapid regrowth was observed following discontinuation of certain chemotherapies. Concurrent administration of anti-VEGF seemed to normalize these accelerated growth rates.
Conclusions: In diverse preclinical models, continuous VEGF suppression provides maximal benefit as a single agent, combined with chemotherapy, or as maintenance therapy once chemotherapy has been stopped. Clin Cancer Res; 16(15); 3887–900. ©2010 AACR.
Translational Relevance
Inhibition of the vascular endothelial growth factor (VEGF) axis is the basis of most antiangiogenic therapies used in the treatment of human cancer. These studies provide evidence that continuous VEGF blockade provides significant benefit in the setting of established progressing tumors and in models of residual disease, either alone or in combination with chemotherapy. Quantification of tumor growth rates both during and after treatment with anti-VEGF found no evidence of tumor "rebound" secondary to selective VEGF inhibition. These studies provide evidence that continuous, prolonged anti-VEGF treatment delays the growth of established tumors and may prevent regrowth of some residual tumors. Finally, we characterize a large panel of tumor xenografts for their varied dependence on VEGF, thereby defining models for characterization of other antiangiogenic agents that may complement or augment anti-VEGF therapy.
Angiogenesis has long been associated with aggressive tumor growth (1), leading to the proposal that blocking this process may be a viable for the treatment of cancer (2). The discovery of vascular endothelial growth factor (VEGF) as a major regulator of endothelial cell growth and survival (3, 4) paved the way for translating these concepts into clinical practice, and validation of this approach came in 2004 with the approval of the anti-VEGF monoclonal antibody (mAb) bevacizumab for the treatment of metastatic colorectal cancer in combination with standard chemotherapy (5). Bevacizumab has now been approved by the Food and Drug Administration for use in combination with chemotherapy/immunotherapy in colon, breast, lung, and renal cell cancers and as a single agent in glioblastoma. Additional antiangiogenic agents, such as sunitinib, sorafenib, and pazopanib, have also been approved as single agents in specific indications, further substantiating this approach to cancer therapy.
Debate continues over the optimal duration of bevacizumab treatment, prompting additional preclinical and clinical studies to address these questions (6, 7). This is of clinical importance because the current paradigm for cancer treatment duration is limited to experience with cytotoxic chemotherapy. The prolonged use of cytotoxic therapy in common solid tumors has, in general, not provided a compelling survival benefit, but has instead resulted in increased cumulative toxicities (8, 9). These findings have raised the question whether treatment until tumor progression with current cytotoxics and bevacizumab provides clinical benefit for patients.
Data from clinical studies suggest that longer duration of bevacizumab treatment may result in improved patient benefit. Analysis of a large randomized phase III study (NO16966) evaluating bevacizumab in first- and second-line therapy metastatic colorectal cancer (10) showed that there was an unexpectedly high incidence of premature discontinuation of bevacizumab (e.g., due to chemotherapy-associated cumulative toxicity), and further analysis revealed a more pronounced clinical benefit in patients who continued on bevacizumab [hazard ratio, 0.63 (P < 0.0001) versus 0.83 (P = 0.0023) for prespecified on-treatment PFS end point compared with the general treatment PFS end point]. This analysis suggests that continuation of bevacizumab until disease progression is necessary to optimize the clinical benefit.
Recent efforts have focused on understanding the biological properties of tumors following discontinuation of first-line therapy, with reports of "tumor rebound" (11–14), or the emergence of a more aggressive and invasive disease following discontinuation of antiangiogenic therapy (15–18). These reports followed the observation of rapid tumor revascularization after discontinuation of a VEGFR tyrosine kinase inhibitor (TKI; ref. 19). Clinical evidence suggestive of rebound following discontinuation of bevacizumab has been reported from a limited patient series (12) or from analytic modeling of clinical trial data sets (14), but has not been rigorously addressed.
Based on these clinical results and a number of reports of rebound and adaptive evasion in response to angiogenic blockade, we conducted preclinical studies to better describe the tumor regrowth kinetics after discontinuation of anti-VEGF treatment. These studies are intended to determine if there is rationale for prolonged treatment duration, including treatment beyond progression, and if there is evidence for growth beyond control rates on cessation of an anti-VEGF mAb. A better understanding of these angiogenic mechanisms could have a significant effect on the management of patients.
All studies were conducted in accordance with the Guide for the Care and Use of Laboratory Animals, published by the NIH (NIH Publication 85-23, revised 1985). The Institutional Animal Care and Use Committee approved all animal protocols.
Characterization of murine and human cross-reactive anti-VEGF mAbs
Measurement of the relative binding affinity in solution was done by ELISA and surface plasmon resonance as previously described (20).
Pharmacokinetic analysis of anti-VEGF antibodies
A single-dose pharmacokinetic study was done for two anti-VEGF mAbs, B20-4.1 and B20-4.1.1. A single i.v. bolus dose of 5 mg/kg for B20-4.1 and a single i.v. dose of 5, 15, or 25 mg/kg for B20.4.1.1 were administered to mice. Serum samples were collected from three animals in each group at various time points and analyzed in triplicate using an ELISA as previously described (20). Serum concentration-time profiles were used to estimate pharmacokinetic parameters for B20-4.1 and B20-4.1.1 by noncompartmental analysis using WinNonlin Model 201 (WinNonlin-Enterprise, version 5.1.1, Pharsight Corporation).
Tumor model studies
For cell transplant studies, cultured tumor cells were resuspended in PBS and implanted s.c. into the right flank of naïve mice as described in Supplementary Methods. Mice with tumors of a mean volume of 80 to 200 mm3 were grouped into treatment cohorts of 10 mice each. For genetic model studies, we used RIP-TbAg mice, which were a transgenic insulinoma model that phenocopy the RIP1-Tag2 mice10 that were treated as noted in Supplementary Methods. Anti-VEGF antibody was administered in PBS at 5 mg/kg twice weekly for 3 to 5 weeks unless otherwise noted. Additionally, chemotherapeutic agents were dosed for selected experiments as noted. Body weights and caliper measurements were taken twice per week during the study.
For analysis of growth rates during and after anti-VEGF treatment, mixed-effect models were used to model tumor growth profiles over time (see Supplementary Methods).
All data were fit and plotted using the ns, lme, and xyplot functions in R version 2.9.0 statistical software.11 Relative growth inhibition (Table 1; Fig. 1A) was determined for each individual tumor study {100 − [2(anti-VEGF growth rate − control growth rate)] × 100}.
Growth characteristics and response to anti-VEGF treatment of various tumor cell lines
In vivo response of tumor xenograft lines to anti-VEGF treatment. A, RGI of various tumor xenograft models during treatment with anti-VEGF. Models are ordered from the most responsive to the least responsive. B, control growth rate [log2(mm3)/d] for a panel of tumor models. Values are ordered from fastest to slowest growth rates. C and D, representative examples of early- and delayed-onset growth inhibition, which reflect two distinct patterns of response to anti-VEGF treatment. Best-fit curves were generated for control (black) and anti-VEGF (red) treatment groups. In models depicting an early-onset response (C) typified by A375 cell line, the two curves separated before 7 d after initiation of treatment. In models depicting a delayed-onset response (D) typified by DLD-1, the two curves were overlapping for a minimum of 7 d and did not separate until later time points.
Histology and staining
Tumors were fixed in 10% neutral buffered formalin for 12 to 16 hours before paraffin embedding. Histologic sections (4-5 μm thick) were stained with H&E as described previously (21). Vascular density was assessed in MECA-32 (anti-PLVAP)-stained histologic sections of tumors, essentially as described previously (22). For each tumor, three representative images, centered 500 μm from the tumor margin, were analyzed.
Pharmacokinetic properties of human-murine cross-reactive anti-VEGF antibody
Modeling the therapeutic activity of VEGF blockade in human xenografts requires reagents that can effectively and specifically neutralize both human and mouse VEGF because both tumor and host stromal elements are known to contribute VEGF to drive tumor angiogenesis (20). Furthermore, use of genetically engineered mouse models (GEMM) requires "murinized" antibodies that recognize murine VEGF and have nonimmunogenic backbones to allow for extended dosing in immunocompetent animals (23). Many of the issues related to species compatibility of VEGF inhibitors could be avoided through the use of VEGFR-targeted TKIs. However, such agents do not serve as good surrogates for selective VEGF blockade because their activity within the VEGF axis is much broader than that of a VEGF mAb. These TKIs also have activity against additional receptor tyrosine kinases beyond VEGFR2 (19), making it difficult to attribute any observed biology exclusively to inhibition of VEGF signaling. We therefore chose to use a VEGF-specific function-blocking mAb in our preclinical studies. Bevacizumab is selective for human VEGF, but has barely any detectable binding to murine VEGF (20). Two series of cross-species reactive function-blocking mAbs targeting VEGF (B20, G6) have previously been described (20). These antibodies were identified for their ability to selectively neutralize all isoforms of VEGF-A, with no detectable activity against the related VEGF-family ligands, including placental growth factor, VEGF-B, VEGF-C, and VEGF-D (20). For this study, we selected the B20 series of anti-VEGF antibodies as a surrogate for preclinical modeling of bevacizumab activity because they have VEGF affinities similar to bevacizumab, yet effectively block both the human and the murine ligands (20). Two optimized clones were developed for in vivo studies, B20-4.1 and the variant B20-4.1.1, which has been optimized for recombinant production in mammalian cells.
Both B20-4.1 and B20-4.1.1 IgGs have relative affinities to human (EC50, 0.20 and 0.17 nmol/L, respectively) and murine VEGF (EC50, 0.39 and 0.17 nmol/L, respectively) that are similar to that of bevacizumab binding to human VEGF (EC50 = 0.40 nmol/L). These affinities are consistent with their potency in inhibiting VEGF-stimulated endothelial cell growth (data not shown). Single-dose pharmacokinetic data were obtained for each antibody, and dosing regimens were simulated that would result in a minimum trough concentration at steady state (Cmin ss) of ∼30 μg/mL, similar to that achieved in >90% of bevacizumab patients. The simulation indicated that this Cmin ss would be predicted for both B20-4.1 and B20-4.1.1 at a dose of 5 mg/kg twice a week or 10 mg/kg weekly (Supplementary Table S1). In addition, serum samples collected from an efficacy study in RIP-TbAg mice with B20-4.1.1 dosed at 5 mg/kg twice a week resulted in a Cmin ss of 43.9 ± 12.1 μg/mL. These results are consistent with the predicted Cmin profile and is above both the target trough concentration for bevacizumab in the clinic and the recommended Cmin for antibodies in preclinical mouse models (24). Based on these analyses, the dosing of the cross-reactive anti-VEGF antibodies in preclinical models is predicted to effectively block >97% systemic VEGF, based on the equilibrium kinetic assumption of % bound VEGF = (anti-VEGF) × 100 / [KD + (anti-VEGF)]. This is similar to what is predicted for bevacizumab use in the clinic (25).
Anti-VEGF has broad efficacy that is influenced by tumor context
Preclinical tumor models support a role for VEGF in all stages of tumorigenesis (23), including early-stage or dormant tumors, to trigger an "angiogenic switch" and initiate the recruitment of a supportive vasculature (26). In established, late-stage primary and metastatic tumors, VEGF continues to influence the tumor vasculature, as evidenced by decreased microvascular density (MVD) on treatment with anti-VEGF antibodies. However, the resulting effect on tumor growth can vary because additional angiogenic factors can compensate for the loss of VEGF, resulting in tumors with varied sensitivities to angiogenic blockade (27–29). Such models can be used to study escape or evasion from anti-VEGF therapy and can help to identify additional angiogenic targeting approaches to be used alone or in combination with anti-VEGF.
To better define the spectrum of primary dependence that tumor xenograft models have on tumor and host-derived VEGF, we evaluated the in vivo effectiveness of anti-VEGF treatment in 30 tumor xenograft cell lines encompassing a number of different tumor types, including breast, ovarian, colorectal, lung, pancreatic, renal, prostate, and lymphoma. Mice were dosed with 5 mg/kg anti-VEGF (B20-4.1) twice a week for 3 to 5 weeks and tumors were measured twice each week. A number of efficacy measures were evaluated including percent tumor growth inhibition (%TGI), defined as the difference between the median tumor volumes of treated and control groups on the last day when all animals remain on study and expressed as a percentage of the control group; time to end point (TTE), time to reach a predefined end point tumor volume where each tumor is measured twice each week; percent tumor growth delay (%TGD), defined as the percent increase in median TTE in the treatment group compared with the control group; and relative growth inhibition (RGI), percent decrease in the slope of the log2 fitted line for the treated group compared with that of the control group's growth curve. We found that %TGD is influenced by the growth rate of the tumor line and the duration of treatment, whereas RGI better reflects the on-treatment effect of anti-VEGF in each of the model.
There is a wide range of VEGF dependence among the 30 tumor lines, as evidenced by the RGI values from anti-VEGF–treated mice (Table 1; Fig. 1A). We attribute the range of responses to the biological differences inherent in donor tissues because multiple studies from a given tumor cell line gave similar results (data not shown). RGI ranged from 77% (most VEGF dependent) to 7% (least VEGF dependent; Fig. 1A). Because multiple tumor types were represented by five or more different cell lines (breast, colorectal, and lung), we evaluated the data for any trends of response based on tumor type. No tumor type–specific patterns were observed. Models such as EL4 and LLC had reduced responsiveness to anti-VEGF and have previously been characterized as refractory models, due in part to the influence of BV8 produced by infiltrating CD11b+Gr1+ monocytes (28, 29). Models most responsive to anti-VEGF treatment included MX-1, OVCAR3, and DLD-1 and were derived from different human tumor donor sources. Percent TGD ranged from 10% (least VEGF-dependent) to >100% (most VEGF dependent; data not shown). Again, no tumor type–specific patterns were observed. Percent TGD is influenced by the growth rate of the tumor line and the duration of treatment, whereas RGI better reflects the effects on tumor growth either during or after treatment. Thus, we have evaluated a series of transplant tumor models and have characterized their sensitivity to anti-VEGF treatment using two different metrics, thereby defining their dependence on VEGF for growth.
To understand the relationship between RGI and %TGD, we also evaluated the correlation between these two metrics. As predicted, we found a correlation (slope of fit = 0.64; P = 0.048) indicating that models that have higher %TGD generally show higher RGI (both being defined as more VEGF dependent; data not shown). In models with high RGI, the near cytostatic response to anti-VEGF translated into an extended time on study and resulted in a delay in reaching the study end point. Interestingly, no such correlation was found between %TGI or TTE and either %TGD or RGI (data not shown). Tumor growth rates varied by 10-fold among the 30 lines, with the most rapid growth observed in the B16, HM7, LL, and A375 models (Table 1; Fig. 1B). Although fast-growing tumors are often stated to be highly angiogenic (30, 31), we saw no correlation between RGI and the control growth rate of these tumors (slope of fit = 0.01; P = 0.97), indicating that anti-VEGF sensitivity was not a function of tumor growth rate (Supplementary Fig. S1). We also evaluated if VEGF dependence was a function of VEGF expression levels. Evaluation of a cohort of models indicated that neither %TGD (data not shown) nor RGI (Supplementary Fig. S2) correlated with tumor VEGF expression levels, confirming the observations made in patient populations (32, 33).
Anti-VEGF treatment resulted in two primary patterns of growth inhibition (Fig. 1C and D). In some models (typified by A375), we saw an almost immediate separation of the growth rate curves of the anti-VEGF–treated versus control-treated animals (Fig. 1C). We termed this pattern "early-onset growth inhibition." In the remaining models, the growth rate of treated animals mirrored the control rate for a brief initial period (4-15 days depending on the cell line) before separating to show reduced growth rate (Fig. 1D). We termed this pattern (typified by DLD-1) as "delayed-onset growth inhibition." Of note, many of the less VEGF-dependent models (low RGI) displayed a delayed pattern, suggesting that although they lacked an immediate response to anti-VEGF, their growth was delayed with continued VEGF blockade. Notably, two other growth patterns were not observed in any of the xenograft models: transient and cytostatic growth inhibition. Transient inhibition would be reflective of an initial growth delay that then accelerates back to the rate of control-treated tumors while still on anti-VEGF. This pattern might have implicated an adaptive response, development of resistance to VEGF blockade, or selection of a subpopulation of cells within the xenograft that are less dependent on VEGF for growth. A cytostatic response, characterized by a negative growth rate, might have been anticipated in highly VEGF-driven tumors. Although there may seem to be a cytoreductive response to anti-VEGF in newly engrafted tumors, this pattern was not observed in any of the established and actively growing tumor models used in these studies.
Increased efficacy is observed with longer duration of anti-VEGF treatment
Inhibition of VEGF by selective mAbs may essentially be considered irreversible due to the high kon and low koff of these reagents [B20-4.1 hVEGF: kon = 2.4 × 104 (mol/L)−1 s−1, koff = 0.41 × 10−4 s−1, KD = 1.7 nmol/L; B20-4.1 mVEGF: kon = 4.8 × 104 (mol/L)−1 s−1, koff = 1.1 × 10−4 s−1, KD = 2.3 nmol/L; B20-4.1.1 hVEGF: kon = 7.1 × 104 (mol/L)−1 s−1, koff = 5.94 × 10−4 s−1, KD = 8.3 nmol/L; B20-4.1.1 mVEGF: kon = 5.6 × 104 (mol/L)−1 s−1, koff = 5.66 × 10−4 s−1, KD = 10.1 nmol/L, based on 1:1 monovalent binding fitting]. However, the continuous production of VEGF by both tumor and host stromal cells and the local sequestration of VEGF by heparin binding matrix components (34) would suggest that prolonged and continuous inhibition might be necessary for most effective inhibition of tumor growth. To evaluate this, we conducted a number of preclinical studies in established xenograft tumors, comparing short-term anti-VEGF treatment with treatment for the entire duration of the study (end of study). SW620 colon cancer xenografts were allowed to grow to 600 mm3, after which they were treated with control antibody, anti-VEGF for 3 weeks, or anti-VEGF until the end of study. Short-term anti-VEGF treatment caused a rapid and constant growth delay consistent with the 45% RGI seen on treatment of smaller 200-mm3 tumors (Table 1). There was also a 16-day extension of the median TTE compared with control animals. Long-term, continuous exposure to anti-VEGF maintained this level of growth inhibition with a 25-day extension of the median TTE. The Kaplan-Meier plot reveals the survival advantage offered by short- and long-term anti-VEGF treatment, with longer-duration VEGF blockade resulting in optimal outcome (Fig. 2B). Interestingly, the short-term treatment group exhibited tumor regrowth and a reduction in survival starting approximately 1 week after the last dose of anti-VEGF. Additional preclinical studies in moderately anti-VEGF–responsive human breast (MDA-MB-231) and non–small-cell lung (A549) cancer models also showed a delay in tumor growth (data not shown) and improved survival (Supplementary Fig. S3) with both short- and long-term VEGF blockade. This effect was independent of anti-VEGF sensitivity because Bx-PC3 (anti-VEGF sensitive model) and H460 (anti-VEGF refractory model) both showed improved survival (Supplementary Fig. S3) with longer-duration therapy. Together, these data are consistent with the idea that continuous VEGF suppression exerts a cytostatic effect and delays the growth of established tumors, and that treatment withdrawal is followed by regrowth of tumors likely due to the ability of active VEGF to continue to promote angiogenesis.
Increased anti-VEGF efficacy is observed with longer duration of treatment in xenograft and GEMM tumor models. A and B, mean tumor volume (A) and Kaplan-Meier survival plots (B) for SW620 colon cancer line treated with control (black), anti-VEGF for 3 wk (red), or anti-VEGF for the duration of the study (10 wk; orange). A, anti-VEGF treatment for 3 wk resulted in reduced tumor growth compared with control tumors, whereas longer-term treatment resulted in slower growth compared with the other groups. EOS, end of study. B, similarly, treatment with anti-VEGF for 3 wk resulted in increased survival benefit compared with control-treated mice; treatment with anti-VEGF for 10 wk resulted in a further improvement in survival. P < 0.05, between control and 3 wk of anti-VEGF and between anti-VEGF for 3 wk and anti-VEGF to end of study (log-rank test). C to E, increased survival (C) is also observed with longer-duration treatment in the RIP-TbAg GEMM of pancreatic islet cell carcinoma. Compared with control (red) animals, short-term treatment for 2 wk (blue) did not show significant survival benefit. However, longer-term treatment to end of study (green) significantly improved survival compared with the other treatment groups. P < 0.05, between short-term and long-term anti-VEGF treatment (log-rank test). D, tumors from animals that died 5 or more weeks after initiation of treatment were also evaluated for MVD. Short-term anti-VEGF treatment for 2 wk did not result in a significant difference in final MVD in the treated versus control group, as assessed by MECA-32 staining at ∼3 wk after last dose of anti-VEGF. However, anti-VEGF treatment to end of study did result in a significant reduction of MVD. Points, average density of each tumor. Significance was calculated by t test. E, representative examples of MECA-32–stained tumor vasculature (green) in the three groups [control (left), short-term anti-VEGF treatment (anti-VEGF q7d × 3; middle), and longer-term anti-VEGF treatment (anti-VEGF q7d to end of study; right)]. Micrographs are shown from tumors harvested at approximately 5 wk after the start of treatment at low magnification (×100; top row) and at higher magnification (×200; bottom row). Note that tumors on longer-term anti-VEGF treatment have less vasculature than control tumors or short-term anti-VEGF–treated tumors. Tumor nuclei are stained with 4′,6-diamidino-2-phenylindole (blue) in the low-magnification images to facilitate visualization of the tumor mass.
The vasculature of implanted human xenograft tumors is structurally distinct from that of human tumors (35, 36). We therefore wanted to evaluate the effect of longer-duration anti-VEGF treatment on tumors that arise endogenously in orthotopic organs. The RIP-Tag genetically engineered model of pancreatic islet cell carcinoma has been extensively used for evaluating the role of antiangiogneic therapy in tumor treatment (37). This model has a stereotypic and autochthonous vasculature that develops through neoplastic progression of the lesions. These GEMMs of cancer are thought to be more representative of human tumor vasculature. Previous studies in this model have shown that the early preneoplastic lesions are highly dependent on VEGF through week 10, but following activation of the angiogenic switch and development of multiple solid tumors, they recruit additional angiogenic factors and become less dependent on VEGF (26). We have used a conditional variant of this model, termed RIP-TbAg, in which the expression of SV40 large T-antigen is driven by a RIP-FLP transgene. This RIP-TbAg model maintains the same temporal progression of multistage islet cell carcinogenesis as RIP-Tag2 and also exhibits a similar response to early intervention (before week 10) with anti-VEGF that results in a dramatic reduction of tumors. However, late intervention, at 11.7 weeks, with short-term anti-VEGF treatment (2 weeks) showed little effect on overall survival (Fig. 2C, blue versus red lines). However, when these older animals remained on anti-VEGF until end of study, there was a modest but significant improvement in overall survival compared with the control-treated group (15.1 versus 14.3 weeks, P < 0.05; Fig. 2C, green versus red lines). To better understand the lack of benefit following short-term anti-VEGF treatment, we evaluated the vasculature of the treated tumors, both early (1 week) and late (∼3 weeks) after stopping treatment. At the early time point, treatment with anti-VEGF caused a significant decrease in MVD (data not shown). Thus, although there was not a robust effect on tumor growth in response to 2 weeks anti-VEGF treatment, this unresponsiveness was not the result of "resistance" to VEGF blockade. Instead, it seems that the Rip-TbAg tumors do not require excessive vascularization for their growth. Three weeks after stopping anti-VEGF treatment, the MVD returned to the level of control-treated animals (Fig. 2D and E). However, mice on extended anti-VEGF treatment maintained a reduced MVD, suggesting that continuous suppression of tumor vasculature translates into increased efficacy.
GEMMs have recently been generated that recapitulate the development, progression, and pathophysiology of human lung and pancreatic cancers (35, 36). These models are based on tissue-specific activation of key molecular drivers for each disease (KRas and p53 for non–small-cell lung cancer, Rb and p53 for small-cell lung cancer, and KRas and p16/p19 for pancreatic ductal adenocarcinoma) and exhibit similar histopathology to their human counterparts. The endogenously derived vasculature present in these tumors is structurally similar to that observed in human disease and provides a unique opportunity to evaluate the efficacy of therapeutic regimens containing antiangiogenic agents. Response to anti-VEGF in these models correlated with the responses observed in the clinic because VEGF blockade promoted a significant and durable response, both alone and in combination with chemotherapy in the non–small-cell lung cancer model, yet had only a modest and transient response in the pancreatic adenocarcinoma model (data not shown). These GEMMs complement the xenograft models and provide further support that continuous VEGF blockade delays progression and prolongs survival.
Increased efficacy of anti-VEGF in combination with chemotherapy
Bevacizumab is approved for use in combination with a number of chemotherapy regimens in colon, lung, and breast cancers. We therefore tested the ability of anti-VEGF combined with the maximum tolerated dose of several cytotoxic agents to characterize the influence of chemotherapy class, tumor type, and disease setting on response. In the moderately VEGF-dependent MDA-MB-231 breast tumor model, 5 days of treatment with paclitaxel had a strong cytoablative effect, resulting in a 40% to 100% objective response rate in several studies. A representative study is shown in Fig. 3. However, in all studies, the tumors regrew at approximately 4 weeks after completion of paclitaxel treatment (Fig. 3A and C), indicating that residual cells were able to survive chemotherapy and subsequently reconstitute the tumor. Concurrent treatment with anti-VEGF had both early and late effects on tumor growth. The combination resulted in an initial objective response rate of 90%, with more complete responses than seen with chemotherapy alone (50% versus 10%, respectively). However, if anti-VEGF was stopped after 3 weeks, the objective response rate deteriorated by the end of study (Fig. 3C and D) and tumors regrew at a rate similar to animals receiving single agent paclitaxel (Fig. 3C). We then asked what effect extended anti-VEGF maintenance therapy would have on recurrence of tumors in this residual disease model. When anti-VEGF was continued for 7 weeks after chemotherapy, 60% of these early responses were sustained, often resulting in no detectable tumors even at 50 days after stopping the anti-VEGF treatment (Fig. 3D). This posttreatment disease-free interval is longer than the dormancy period of 4 weeks observed with single agent paclitaxel and extends beyond the time of systemic VEGF inhibition, suggesting additional synergistic activity with prolonged anti-VEGF treatment. The Kaplan-Meier and TTE plots (Fig. 3B and E) highlight the benefit of extended maintenance anti-VEGF following chemotherapy (Fig. 3B). The early and late effects of anti-VEGF in combination with taxanes were observed in several other tumor xenograft models of various solid tumor origins, including the anti-VEGF–refractory model SKMES and the anti-VEGF–sensitive models Bx-PC3 (Supplementary Fig. S4) and MV-522 (data not shown), suggesting that this finding is not specific to a single tumor type and is consistent across models with varied anti-VEGF sensitivities. Future studies will follow animals for several months after stopping all therapies and will evaluate for histochemical evidence of residual tumor.
Anti-VEGF extends the activity of cytotoxic chemotherapy and significantly delays regrowth of residual tumors. A and B, mean tumor volume (A) and Kaplan-Meier survival plots (B) for MDA-MB-231 breast cancer line treated with control (black), paclitaxel (blue), paclitaxel plus 3 wk of anti-VEGF (solid purple), or paclitaxel plus 7 wk of anti-VEGF (dashed purple). A, treatment with paclitaxel results in an effective cytoreduction of the tumor mass, although tumors regrow by day 40, indicating the survival and recurrence of residual disease. Addition of anti-VEGF for 3 wk to paclitaxel extends the duration of disease-free survival, whereas addition of anti-VEGF for 7 wk extends this benefit. B, anti-VEGF treatment and paclitaxel treatment result in significant (P < 0.05) survival benefit compared with control treatment. A significant (P < 0.05) further improvement is observed with the combination treatment, reflecting increased tumor growth inhibition. However, the overall survival is significantly improved (P < 0.05) with longer duration of anti-VEGF combination therapy. Significance was calculated by log-rank test. C, growth curves for each animal in the control, paclitaxel, and the two combination treatment groups. Regrowth after paclitaxel treatment occurs in a stochastic manner at approximately 4 to 5 wk after treatment. Tumor regrowth is delayed when anti-VEGF is added to paclitaxel treatment. Extended treatment with anti-VEGF results in a further reduction in the number of animals exhibiting tumor regrowth. D, individual tumor growth volumes at the end of study (d90) show that whereas paclitaxel treatment resulted in inhibition of tumor regrowth in 1 animal, the addition of 3 wk of anti-VEGF to paclitaxel resulted in 4 animals with no tumor regrowth and addition of 7 wk of anti-VEGF to paclitaxel resulted in 6 animals with no tumor regrowth. E, TTE for each animal in the study shows that whereas 2 animals did not reach end point during the course of the experiment when treated with paclitaxel, addition of 3 wk of anti-VEGF to paclitaxel increased this number to 6 animals and addition of 7 wk of anti-VEGF to paclitaxel further increased this number to 9 animals.
Similar combination studies were extended to additional cytotoxic agents to determine if the anti-VEGF effects were limited to a particular class of agents. We observed combination activity with a number of cytotoxic agents including nucleoside analogues (gemcitabine and 5-fluorouracil), anthracyclines (doxorubicin), platins (carboplatin and cisplatin; Supplementary Fig. S4), topoisomerase I inhibitors (CPT-11), and other taxanes (docetaxel; data not shown). Additionally, this effect did not seem to be model or tumor type dependent because a number of agents including paclitaxel and gemcitabine showed efficacy in multiple tumor models (Supplementary Fig. S4). Generally, these models followed a similar pattern of a profound response to chemotherapy followed by eventual regrowth weeks after the cessation of treatment. In many instances, anti-VEGF treatment was able to significantly delay or prevent the regrowth of the tumors. More than 100 studies were done. We saw additive activity of anti-VEGF and chemotherapy in ∼25% of the studies, and importantly, in the remaining 75%, we saw no evidence of antagonism in any of these combinations (data not shown). These findings suggest that anti-VEGF is able to extend the activity of many cytotoxic agents and that this is likely mechanism specific.
These residual disease models provide preliminary evidence that longer-duration anti-VEGF not only delays regrowth of residual tumors but may also result in sustained and durable inhibition of tumor growth. Conceptually, there may be a limited length of time in which these residual tumors can survive without activating an angiogenic switch and recruiting vasculature. What is currently unclear is whether extended VEGF depletion may ultimately lead to the demise of such tumors, leading to prevention rather than just delay of recurrence.
No evidence of rebound on cessation of anti-VEGF therapy
Our analysis in a diverse collection of tumor lines shows that, during treatment, anti-VEGF causes a reduction in the tumor growth rate. Recent reports have postulated a "rebound phenomena" of increased growth of tumors and their vasculature following discontinuation of an angiogenic blockade (11–19). These studies generally use multispectrum VEGFR-targeted kinase inhibitors, or VEGFR2-targeted antibodies, and surprisingly, none have actually quantified the growth rates of treated and recovering tumors. We sought to quantify tumor growth rates following selective blockade of VEGF with anti-VEGF neutralizing antibodies. We calculated the growth rate of tumors during the recovery period, which we defined as the period following the last dose of anti-VEGF, and compared this rate to that observed in control-treated tumors. A 10-day period for antibody washout was used to ensure that no direct anti-VEGF–mediated effects were included in the calculation. In 25 of 26 cases (96%), we found the recovery rate to be less than the control rates, arguing against the existence of rebound following release of an angiogenic blockade (Fig. 4A). Only a single tumor line (SKMES) showed an increased recovery rate following anti-VEGF treatment. To identify the factors that influenced the tumor regrowth rates, we evaluated a number of parameters, including VEGF expression levels, control tumor growth rate, and growth rate while on anti-VEGF treatment. The only significant correlation identified was between the rates of tumor growth during and after treatment with anti-VEGF (Supplementary Fig. S5). Examples of tumor growth curves for anti-VEGF–sensitive (MX-1, SKOV-3), moderately anti-VEGF–sensitive (MCF-7), and anti-VEGF–refractory (Panc-1) tumor models show that no increased growth rates are observed regardless of anti-VEGF sensitivity (Supplementary Fig. S6).
Cessation of anti-VEGF treatment does not result in tumor rebound. A, graph of change in growth rate for different tumor lines. The difference in growth rate was calculated as the growth rate after anti-VEGF treatment minus the control growth rate. Positive value (gray column) indicates faster growth after cessation of anti-VEGF treatment compared with control. Negative values (black columns) indicate slower growth rate after anti-VEGF treatment compared with control. Note that most tumor lines (25 of 26) show negative change in growth rates. B and C, relative regrowth rate for tumors treated with chemotherapy or chemotherapy in combination with anti-VEGF. Growth rates were calculated by normalizing the regrowth rates of the chemotherapy or the combination groups to the growth rate of the control group. A value >1 indicates faster growth compared with control, and a value <1 indicates slower growth. B, MDA-MB-231 tumors were treated with different chemotherapeutic agents, alone (solid columns) or in combination with anti-VEGF (hatched columns). Analysis of tumor regrowth rates shows that prior chemotherapy generally results in a slower regrowth rate (the exception being gemcitabine) compared with control tumors. Furthermore, this rate was always reduced with concurrent anti-VEGF treatment. C, various tumor lines treated with paclitaxel, alone (solid columns) or in combination with anti-VEGF (hatched columns), showing that anti-VEGF results in reduced regrowth rates compared with tumors treated with single agent paclitaxel.
Because bevacizumab is more commonly used in combination with chemotherapy, we also evaluated the in vivo effects of chemotherapy, both alone and in combination with anti-VEGF on rebound rates. Most tumors grew slower during the regrowth phase after cytoreduction, compared with control rates (black columns, Fig. 4B and C). This blunted growth was seen with multiple chemotherapies in the same tumor model (Fig. 4B) and with the same chemotherapy in different tumor cell lines (Fig. 4C). In a few instances, a significant increase in growth rate was noted following discontinuation of single-agent chemotherapy (gemcitabine in MDA-MB-231 and paclitaxel in Bx-PC3). However, regrowth rates were always lower when anti-VEGF was combined with chemotherapy compared with regrowth rates following single-agent chemotherapy. In the Bx-PC3 model, anti-VEGF cotherapy prevented "rebound" elicited by paclitaxel (Fig. 4C). Taken together, these data suggest that tumor rebound can occur following discontinuation of paclitaxel or gemcitabine, but these uncommon examples of rebound are not associated with discontinuation of anti-VEGF treatment. Furthermore, anti-VEGF treatment has a beneficial effect on regrowth rates both alone and in combination with chemotherapy.
Anti-VEGF treatment showed broad activity in a diverse panel of ∼30 tumor models. These results were expected based on the proposed antiangiogenic mechanism and the acknowledged importance of VEGF to tumor angiogenesis (3, 4). However, we have quantified a surprisingly broad range of responses to anti-VEGF among these models, allowing them to be classified based on their dependence on VEGF for growth. Furthermore, we confirmed the sensitivity to VEGF-axis inhibition in a subset of these models by comparing the effects of anti-VEGF and an intermediate dose of the small-molecule inhibitor of VEGF receptors, ABT-869 (ref. 38; Supplementary Fig. S7). VEGF-dependent models could potentially be used to more thoroughly understand the anti-VEGF mechanism of action (20). By the same token, the VEGF-independent models can be used to study anti-VEGF escape and to identify additional factors (29) that may drive angiogenesis in the context of maximal VEGF blockade. Indeed, such approaches have already provided insights into the tumor microenvironment and have led to the identification of angiogenic and metastatic factors produced by infiltrating immune cells and activated stromal cells (28, 39).
There are multiple end points used in clinical trails to measure response and efficacy. In these preclinical studies, we used %TGD and RGI as distinct metrics of efficacy. We found a correlation between these independent measures, thereby providing increased confidence in each. However, we did not identify any correlation between tissue of tumor origin and efficacy. These findings support the notion that blocking tumor angiogenesis is a broadly applicable approach to cancer therapy but may also imply that the vasculature of cell-transplant tumor models may not faithfully represent the disease from where tumor cells originate. Among the models used in this article, GEMMs may more accurately model human disease because their tumor vasculature develops in concert with malignant progression and may be more suitable for investigating the disease-specific effects of antiangiogenic agents (35, 36).
Target overexpression or pathway activation may correlate with response to a targeted therapy and has led to the development of diagnostics and the selection of patient subsets more likely to respond. Although human tumors that express high levels of VEGF, including renal, ovarian, and glioblastoma, seem to be more responsive to single-agent antiangiogenic therapy than other solid tumors (40), no predictive biomarker has yet been identified for bevacizumab or other antiangiogenic agents (32). VEGF levels have been found to be prognostic for more aggressive tumors, but they have not conclusively been shown to be predictive of response to bevacizumab or other VEGFR-targeted agents (32, 41). In our diverse collection of tumor models, we did confirm high levels of VEGF expression in renal and glioblastoma tumors (Table 1), but found no correlation between tumor VEGF expression and either the growth rate of untreated tumors or their RGI in response to anti-VEGF (Supplementary Fig. S2).
We also examined the effect of treatment duration on response to VEGF blockade. In established tumors, we found that anti-VEGF treatment resulted in two primary patterns of growth inhibition that we refer to as "delayed onset" or "early onset." The majority of models had a delayed onset pattern of growth inhibition where VEGF blockade was not immediately reflected by a change in tumor growth rate. Given that a majority of the antivascular effects of anti-VEGF manifest within the first 48 hours of treatment (42), the exact cause for this delay is unclear and may reflect the excess vascular reserve that is generally found in many biological contexts. Not surprisingly, we also observed improved tumor growth control and survival in mice maintained on an extended course of anti-VEGF. In xenografts, we saw no evidence for an increased rate of tumor growth while remaining on anti-VEGF therapy. However, robust yet transient responses to anti-VEGF have been observed in non–small-cell lung cancer GEMMs, suggesting that these genetic models may be useful for identifying factors responsible for escape or evasion from anti-VEGF treatment.
The influence of treatment duration is likely due to the fact that tumors and host stroma continue to produce VEGF, which, on withdrawal of anti-VEGF, is capable of activating angiogenesis to support tumor growth. This is confirmed by the regrowth of tumor vasculature up to, but not exceeding, the density observed in the control tumor within weeks of stopping anti-VEGF treatment. Similar results are also observed on withdrawal of VEGFR TKIs (11, 19). Additionally, we have observed a similar trend when anti-VEGF was used in combination with chemotherapy both in human tumor xenografts (Fig. 3) and in GEMMs.
We also examined the effect of prolonged VEGF blockade in the setting of residual disease. Cytotoxic chemotherapy can effectively reduce established tumors to yield a partial or complete response. However, residual tumor cells or clusters often remain behind and can lie dormant for weeks to years. Our studies show that these lesions are highly dependent on VEGF and, when appropriately suppressed, exhibit dramatic and durable growth inhibition. Such efficacy is likely due to a failure in their ability to recruit a vasculature and enable these isolated cells to progress and grow to a size that will be detectable by conventional computed tomography scans. Such residual disease models have been used to study the effect of prolonged VEGF blockade following chemotherapy (43–46) and have shown that anti-VEGF therapy primarily functions to delay rather than prevent tumor regrowth. However, we believe that these studies are the first to show that in some models of residual tumor burden, prolonged anti-VEGF therapy can prevent tumor regrowth for prolonged periods. Further studies with longer follow-up and histochemical analysis will be required to determine if this extended treatment would result in durable relapse-free survival.
Recent reports have questioned whether there is a rebound in tumor growth following discontinuation of antiangiogenic therapy with VEGFR TKIs. Because of the multiple targets inhibited by current VEGF TKIs (19), such an effect cannot be attributed exclusively to inhibition of VEGF signaling. Rebound can be defined as an increase in tumor growth rate following treatment withdrawal that exceeds that of placebo-treated controls. To address the specific effect of VEGF inhibition on tumor regrowth, we measured these rates following cessation of therapy with a VEGF-specific mAb in more than 20 models. We found no evidence of accelerated growth beyond that of control tumors. Although it is possible that accelerated regrowth may occur in another time window, we believe this is unlikely to be related to discontinuation of VEGF suppression because our studies spanned a diverse collection of models representing multiple tumor types, varied primary growth rates, and a broad range of VEGF dependence. Additionally, these studies do not address the altered metastatic patterns described with TKI inhibition (47, 48) because most of the models do not have observable metastases. In contrast, we observed a few examples of an increased rate of tumor regrowth following cessation of chemotherapy. This is in agreement with previous reports (44) of tumor rebound following treatment with certain cytotoxic agents, and it may be related to reports of enhanced invasive and metastatic properties of tumors treated with broad-spectrum TKIs (47, 48). However, our studies found that, when combined with chemotherapy, anti-VEGF delays, rather than exacerbates, tumor regrowth. These results suggest that the action of anti-VEGF is mechanistically distinct from those of less specific antiangiogenic agents (17, 48). Although tumor and tumor vasculature regrow after anti-VEGF is cleared from circulation, they do so at a rate, and to a degree (density), consistent with that of an untreated tumor of comparable size.
Tumor models with a wide range of dependence on VEGF provide evidence that continuous VEGF blockade is required to maximize benefit as a single agent, combined with chemotherapy, or in the maintenance setting. We also find no evidence of excessive or aggressive tumor regrowth or vascular "rebound" once VEGF blockade is discontinued. These data provide a rationale for considering the use of bevacizumab with various lines of chemotherapy or for considering longer-maintenance use in early-stage disease.
All authors except B. Hollister are full-time employees of Genentech, Inc.
We thank the Genentech employees, Sarajane Ross and Jennifer Thompson for their technical assistance with the in vivo efficacy studies; David Goldenberg for analysis of tumor histology; Laura Sanders for determining tumor VEGF levels; Wei-Ching Liang and Vivian Lee for antibody generation and characterization; Napo Ferrara, Carlos Bais, Jakob Dupont, and Bob Mass for helpful comments; and Chuck Harrison, Cheryl Napier, Kay Meshaw, Alan Meshaw, and Kathy Sheridan at Piedmont Research Center for technical assistance with in vivo models.
Note: Supplementary data for this article are available at Clinical Cancer Research Online (http://clincancerres.aacrjournals.org/).
↵10Singh et al., in preparation.
↵11R: a language and environment for statistical computing, R Development Core Team, R Foundation for Statistical Computing, Vienna, Austria; NLME package authored by Douglas Bates and José Pinheiro.
Revision received April 27, 2010.
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The box was so heavy that Marshall had to help Todd carry it home.
When did Kerri come see you?
Darci was surprised by what he saw.
Andy is mopping the floor.
Leslie told me he wouldn't be late, but he still hasn't shown up.
Did you ever talk to Stanley?
Sergei came close to being run over.
Mann is quite popular, isn't he?
Where is Rod going to get shoes that fit?
Ethan is a professional surfer.
Jenine doesn't know whether the concert went well or not.
Hitoshi seems to have it in for me.
Brent walked out the door without saying goodbye.
Tommy knew Nils needed some food.
Franklin hasn't talked to Ed in years.
Israel is determined to have his way.
Jem was a manager until 2010 when Audrey took over the lead.
Juliet wanted to finish making breakfast before Lanny woke up.
Why are you wearing Tony's jacket?
I'd go visit Nici in the hospital if I were you.
I asked Nathan for Elias's phone number.
Kyung is a pretty stupid guy.
Toerless looked over his shoulders, expecting to see someone.
Peggy reluctantly gave Ramon the money she asked for.
Dana and John were arrested at a local bar.
Stefan's desk was so untidy that the cleaner refused to clean the room.


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"This book was great," is a gross understatement.
While The Longest Ride sparked the fire for reading again, Love Arrives in Pieces really set that fire ablaze.
This book really got me back into my reading like crazy. It was the first book in a long time that I stayed up to read. Like I stayed up past 11pm reading for hours. It was fantastic.
There was just something about this story that had the perfect combination of the realness of human emotions and love, and all the emotions we may experience on that journey.
Stella is an interior designer who is an old beauty pageant star. She has endured some heartache over the past couple years, and is now trying to figure out her true self since she has hidden behind a marriage or tiaras for so long.
Chase is a contractor who just recently lost his fiance in a car accident. Because of this loss, he lives life in the moment and realizes he needs to move back home to reconnect with his family.
Chase and Stella start working together to rebuild a theater in their hometown. During this project they must face their past and overcome some heartache.
The story is about the two of them finding their way and also finding love may not come automatically.
What I enjoyed about this book is the realness. Sometime in romance fiction things may be over dramatized and show the air of a fairy tale set in modern times. This book highlights struggles and insecurities both individuals may face on the way to love. There are obstacles for each person to overcome to be in a place to really put down walls and let someone in like that.
I also really appreciated that God was the center of this book, and not in a overly pushy way. I think sometimes when you read Christian novels they can get preachy and make you think you can never attain that. Again the author was real with how a person would talk to God and look for guidance. It was a reminder that you don't have to have a perfect life to seek out God's help and faith.
I really enjoyed how St. Amant chose her words and the flow of the story. She would give you little pieces at a time of why each character was struggling. It was like she was slowly peeling an onion for you to reveal more layers. She switched between Stella and Chase's point of view, so you could see both perspectives. It's an honest and raw view of how God can take the broken pieces of our past and use them to put us in the right place for something beautiful.
It's been a long time since a book got me good in the gut like this, so I don't know if my heart was just itching for it, but I loved it all the same. I really enjoyed the complexity of the book, one page was deep but yet the next would be light-hearted, which I think sometimes how we portray ourselves in life.
If you are looking for something new, I would definitely recommend this book. There is another book with some of the same characters that I am not sure if it is a prequel since All's Fair in Love and Cupcakes details Stella's sister's love story. But from the excerpt it does look like the timeline of that plot-line proceeds this one. I will definitely be checking that one out.
Have you read any books that have kept you up late reading past your bedtime?
This entry was posted in Books and tagged Betsy St. Amant, Love Arrives in Pieces, reading til dawn. Bookmark the permalink.


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ROCHESTER, NY- July 12, 2016- iV4, Inc., an industry leading IT Consulting, Managed IT Solutions, and Security company today announced it has been named Microsoft's 2016 Northeast US SMB Cloud Partner of the Year. This award solidifies iV4's superior partner performance and commitment to delivering Microsoft cloud solutions to hundreds of clients. iV4 was recognized and received the award at the Microsoft's Worldwide Partner Conference in Toronto, Canada on July 11, 2016.
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iV4 was previously named the Microsoft Northeast SMB Partner of the Year for 2015. The company is a Microsoft Gold Partner and certified in multiple Microsoft Competencies: Gold Cloud Productivity, Gold Datacenter, Gold Midmarket Solutions Provider, Silver Cloud Platform, and Silver Small and Midmarket Cloud Solutions.
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I don't generally do much writing on my blog. Mostly because I'm pretty sure you are here for the pictures instead of the words. But this blog post had to come with the words.
Olivia booked me for their wedding without ever meeting me in person. This isn't something I normally do. I normally like to meet for coffee or at least Skype to make sure it's a good fit photography-wise and personality-wise. But everything Olivia said she wanted in photography, is exactly what I do. And if you know me at all, you know I'm most happy outside and we have a love affair with camping and hiking and the water.
Jim is SUPER into being outdoors, so Olivia planned their wedding around what they love, family and the outdoors. She wanted Jim to love every part of their wedding as much as she knew she would. She wanted portraits but she wanted everything to feel natural and comfortable and candid. This is exactly what I'm about - telling YOUR personal story. Once we arrived at The Gunflint Lodge, I worked with their super accommodating staff to have one of them drive us up one of their dog sledding trails so we could hike around the woods a bit for photos. Jim and Olivia were both so happy to be doing what they loved instead of standing around posing and that is visible on their faces in every picture.
I love these intimate weddings because they're so personal and special. They're not about anything else other than their love, those they love, being where they love, and doing what they love. Big weddings are so beautiful and so amazing but they're not for everyone. If you're one of those that wants or needs to scale back and do something smaller or more intimate for your wedding, reach out to me. I'd love to work with you.


Over at the Washington Post, Paul Waldman notes the Capitol-sized elephant in the room that the candidates in Tuesday night's Democratic debate could not honestly address: Should you win the presidency, how are you going to work with a Congress full of chowder-headed nihilistic conservatives who see opposing your agenda not as a difference of political opinion, but as the defining battle in determining the course of Western civilization?
Okay, Waldman was not that apocalyptic. But the question, which was directed at Bernie Sanders, reminds us that all the attention paid so far to the presidential primaries has obscured one that is just as consequential to the success of a Hillary Clinton or Bernie Sanders presidency: Which party will control the Senate after 2016, and how effective will it be in working with a Democratic president?
Conventional wisdom has it that Democrats have a good chance of retaking the Senate majority just two years after losing it in the 2014 midterms. Of the 34 seats up for grabs, 24 belong to Republicans, some of whom were swept into office in the 2010 Tea Party wave and could get swept right back out again if the voting public decides it has seen enough of that crowd's government-by-temper-tantrum ethos.
If Democrats can snare a net gain of four seats (five if there's a GOP president), they will control the Senate. With the House of Representatives a lost cause for the party until congressional district maps get redrawn after the 2020 census, the fate of any major legislation pushed by a Democratic president will rest in the upper chamber. As anyone who recalls the push to pass Obamacare knows, those first two years are when a new president has the best chance of pushing big-ticket items, so Clinton or Sanders will want to push legislation before the 2018 midterms roll around and possibly give the Senate back to the GOP.
There are some Republican-held seats that are vulnerable to Democratic challenges. In Illinois, the native state of Hillary Clinton and adopted home of Barack Obama, Rep. Tammy Duckworth has an excellent chance to knock off Sen. Mark Kirk. (She must first get past a spirited primary challenge from former Chicago Urban League president Andrea Zopp.) In Wisconsin, former Senator Russ Feingold could take the seat he lost in 2010 back from Ron Johnson, whose major accomplishments in office involve mostly sounding like a snarky jackass, a job usually better left to political opinion writers. Democrats also have a good shot at picking up currently Republican-held seats in New Hampshire, Florida and Ohio.
So Democrats grabbing the Senate and being able to write some legislation is quite possible -- though it's questionable how progressive it will be if Wall Street bagman Chuck Schumer, as expected, takes over as majority leader for the retiring Harry Reid. But that is a fight to be had after the election.
Of course the Republicans will fight any Democrat in the White House. We should assume Mitch McConnell's goal, should he revert to being the minority leader come January of 2017, will once again be to deny the president a second term. And if the GOP holds onto the Senate, the likely governmental paralysis that results if McConnell is still a majority leader saddled with a flat-out crazy person installed as Speaker of the House (a distinct possibility) is almost too depressing to comprehend.
Neither of the two front-running Democrats has a good strategy for dealing with congressional gridlock, probably because there isn't one. Hillary Clinton recently made some noise about using executive orders to implement her agenda, but even that approach has pretty severe limits legally. Sanders in his debate answer talked about a "revolution" with "millions of people coming together" and "giving the Republicans an offer they can't refuse" and promising to look elected legislators in the eye and tell them that Bernie's Army will push them out of their jobs if they don't get with the program, an approach so laughable for reasons ably described by Waldman that you had to wonder if the candidate was shrooming when he suggested it. (It's not the first time Sanders has suggested this course of action.) The days of using leverage like earmarks against congressional reps are over; it's not 1967 and Bernie Sanders is not Lyndon Johnson.
Still, in terms of pushing the country to the left on at least a few issues, putting Democrats back in charge of the Senate is an important step. Even with a moderate like Hillary Clinton in the White House (the leftier-than-thou scolding of dunderheads who think that online click-bait polls represent a groundswell carrying Bernie Sanders inexorably to the nomination notwithstanding). It's not going to be a big step forward. But progress in our system comes slowly when it comes at all.


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In 1973, a spiritual awakening captures the hearts of the Woodlawn High School Football team. Lead by their coach, Tandy Geralds, and fueled by the team's dedication to love and unity in a school filled with racism and hate, the team makes an astounding run at the playoffs, leading to the largest high school football game ever played in the torn city of Birmingham, Alabama, and the rise of its first African American superstar - Tony Nathan.
Balto III: Wings of Change
Join the world's most courageous dog in his third animated adventure through the frozen north! A daring airplane pilot claims he can deliver mail and supplies faster than a sled dog team, but when his plane crashes on the side of a mountain, it's up to Balto and his pals, including his pup Kodi, to prove their worth by bringing help where it's needed. Featuring the voice talents of Sean Astin, Keith Carradine, Jean Smart and Kathy Najimy, it's a fun, heartfelt, high-flying adventure that proves...
A dozen different souls – all moving in different directions, all longing for something more. As their lives unexpectedly intersect, they each are about to discover there is power in the Cross of Christ… even if they don't yet believe it. When a local pastor is shaken to the core by the visible faith of an old street-corner preacher, he is reminded that true belief always requires action. His response ignites a faith-fueled journey that powerfully impacts everyone it touches in ways that only...
Balto 3-Movie Adventure Pack
Experience the complete adventures of one of the most courageous canines of all time with the Balto 3-Movie Adventure Pack ! Inspired by an incredible true story, the original film follows Balto as he braves an Arctic storm to retrieve life-saving medicine for Alaska's children. In Balto II: Wolf Quest , the hero returns in a breathtaking new quest to help his daughter Aleu discover her wolf heritage and fulfill her own heroic destiny. Balto rises to the challenge once again in Balto III: Wings...
Films of Faith 3-Movie Collection (The Case for Christ / Do You Believe? / I'm Not Ashamed)
The Case for Christ : Working to disprove the growing Christian faith of his wife, an investigative journalist chases down the biggest story of all time…with unexpected, life-altering results! The Case of Christ is based on the true-life story of Lee Strobel, author of the bestselling book. Do You Believe? : When a pastor is shaken to his core by a street-corner preacher's courage, the ensuing faith-fueled journey is a powerfull reminder that true belief always requires action. I'm Not Ashamed...
Films of Faith 3-Movie Collection (God's Not Dead / Woodlawn / Indivisible)
God's Not Dead : When an atheist Philosophy professor (Kevin Sorbo) plans to forego "dusty arguments" in his class, he insists the new students declare that "God is dead." Unable to do this, Josh (Shane Harper) is challenged to defend his faith and prove to the class that God's Not Dead . Against all odds, Josh stands up for his faith and takes on the challenge. Woodlawn : In 1973, a spiritual awakening captures the hearts of the Woodlawn High School football team. Led by their coach, Tandy...

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April 16, 2020 By Helen Brown Leave a Comment
Prospect Research for the Here and Now
In the midst of any crisis, after the first moments of stopping and taking stock of what is happening around us, the next thing people normally do is jump into action to help. This week my colleague Grace Chandonnet shares her perspective on practical ways that we in prospect research can jump into action to be helpful to our organizations. Be well. ~Helen
We're a few weeks into the new (for now) normal and lucky to be in an industry that lends itself well to remote work. It seems like a good time to be strategizing around ways to get through an economic downturn with our organizations intact, and also a good time to look ahead and prepare for the future.
I've been thinking about things that we fundraising intelligence pros can do to make the present moment more productive and satisfying that will also help prepare us to move ahead through – and past – turbulent times. Here are some practical things that we can do now.
Projects and Planning
This might be a good time to consider all those things on your to-do list that you never seem to have time to fit in. What can you be doing to look to the future and be ready to hit the ground running when we emerge? For example:
In-person events are off the table right now, but can you work on prospecting projects for future event attendees?
Now is a great time to plan and implement analytics projects to find the hidden gems in your own databases. Consider appending free or inexpensive data to make your data insight projects even more robust.
Research and draw relationship maps to identify strong prospects who might know your organization's friends and family and want to be engaged?
If you're working at a school or university, now is a good time to re-imagine your parents research programs as we're heading into summer.
Supporting the Front Line
Now is a great time to be looking for additional ways to support our frontline fundraisers. Our extroverted colleagues may be really struggling in a time of enforced social distancing. The logistics of business as usual – building relationships with donors and prospects – has been suddenly altered drastically. If you're a prospect development pro, take the opportunity of having more planning time with frontline colleagues and discuss their priorities and concerns to strengthen your relationships with them.
Work with fundraisers to help them re-balance their portfolios to set them up for future success. This could include re-assessing capacity with an eye toward the industries that are recession-proof vs. those that might not be – we can lead these discussions and also touch on the overarching economic outlook.
Use the aforementioned analytics and prospecting projects to target the prospects that will help fundraisers meet their visit and solicitation goals.
Set up some interactive trainings or presentations geared toward frontline fundraisers – perhaps a quick training on basic research – to give them tools for things that they can do themselves to get ready for a meeting or phone call when there is no time for formal research.
It might also be a good time to focus on process-oriented training, such as short sessions on entering research requests, prospect management moves, and/or contact reports into your organization's CRM.
Now might also be a great time to host a few virtual coffee breaks – that have no set agenda – with small groups of fundraisers and you or your team of researchers just to get to know each other a little better.
Take advantage of trainings and webinars
We can also be focusing on our own professional development. Apra and many of its chapters as well as familiar vendors like iWave and DonorSearch offer ongoing, as well as timely and relevant virtual trainings and webinars on a variety of topics relevant to our industry and ways we can weather the pandemic. Is there something that you've been wanting to know more about? Wishing to take a deeper dive into certain industries, or know more about the hands-on intricacies of data analytics? With fewer research requests in the queue, it could be a good time to set aside some time for some of these free training opportunities.
"Self-care" is an oft-used expression that means different things to different people, but there is no doubt that most of us are experiencing an increase in stress and anxiety, and a little self-care couldn't hurt. It's more important than ever to take a few minutes during your day to stand up and stretch, step outside and maybe take a walk around the block (as weather and social distancing guidelines allow), try out a meditation app, or to just sit quietly and breathe for a few minutes.
I do believe that our industry will weather this. We are a resourceful bunch (literally!) and we've been through troubled waters before. Let's have each other's backs and we and our organizations can emerge stronger than before.
Filed Under: Career development, Non-profit trends Tagged With: Grace Chandonnet, practical tips, prospect research
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David's career in prospect research began in 2009, as a graduate research assistant at the Shippensburg University Foundation. In 2011, He became a development researcher for the University of Virginia. In 2015, David became assistant director of prospect research at the University of Baltimore, serving for 3 years. Recently, he was the director of development for Trees Forever. David Joined the Helen Brown Group as a research assistant in January 2020. He earned a B.A. in Theater at Indiana University of Pennsylvania and a M.A. in Applied History at Shippensburg University. David is a member of APRA and APRA Great Plains.
Kenny has worked in development since 1999 and has been involved in prospect research since 2002.
Prior to joining The Helen Brown Group, he was the director of donor and prospect research at the United Way of Massachusetts Bay. Kenny is a member of APRA and NEDRA.
Tara first began her career in development in 2002 supporting the Major Gifts department at Simmons College, and ultimately went on to serve as Assistant Director of Prospect Research. Since that time, she has also worked as a Senior Research Analyst at MIT, as Associate Director of Prospect Management and Research at the Harvard Graduate School of Education, and as Director of Development Research at Combined Jewish Philanthropies (CJP).
Tara originally joined the Helen Brown Group team in 2007 and served as a Research Associate and ShareTraining coordinator until 2008 – she rejoined the company as a Senior Researcher in 2013 and was promoted to her current role in 2018.
She has been an active volunteer with NEDRA for many years and served on the board of directors from 2010-2016. During her time on the NEDRA board, she served in many different roles, including terms as Vice President, Secretary, Chair of the Website and Technology Committee, Chair of the Volunteer Committee, and as Chair and Editor of NEDRA News. She is currently a member of the NEDRA Bootcamp faculty. In addition, Tara has also been involved as a volunteer with Apra, serving stints on the Membership Committee, Chapters Committee, and Bylaws Task Force.
Angie began her career in development in 1999 at Virginia Tech in Corporate and Foundation Relations and later in prospect research at the University of Connecticut Foundation.
A graduate of the University of Tennessee at Martin, her experience includes grants management at the University of South Carolina, program evaluation for South Carolina Research Authority and human resources analysis for Nissan North America.
She returned to development in 2007 and worked in various prospect research positions at Vanderbilt University, including Associate Director. She was named Director for Vanderbilt University Medical Center's research office in 2015, and joined The Helen Brown Group in 2016.
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Josh began his career in development as the Phonathon Coordinator at Keene State College. He then worked at non-profit consulting firm Schultz & Williams in Philadelphia.
He started his research career at the University of Pennsylvania as a Research Assistant in 2005. He then moved over to the Wharton School of Business, where he became the Associate Director, Research and Prospect Management. Josh joined the Helen Brown Group in 2016.
Josh is also a Colorado licensed Realtor and graduate of Lehigh University.
In March 2017, Kristina joined the Helen Brown Group as a Research Associate. Before joining HBG, she was the Research Manager at Pratt Institute in Brooklyn and an Associate Manager of Prospect Research at City Harvest, a food rescue organization. Kristina started her non-profit career as a legal assistant at the Metropolitan Museum of Art in 2004. She is a member of Apra and Apra Greater New York. She was Apra Greater New York's Director of Programming from June 2014 to May 2016. Kristina graduated from The University of Chicago and the Bard Graduate Center.
Grace began her career in development in 2001 as Executive Assistant to the Chief Development Officer with Brigham and Women's Hospital (BWH), a Harvard Medical School-affiliated academic medical center.
In 2003, she became a prospect researcher for the BWH principal and major gifts team and spent the next 11 years in various research positions with BWH, culminating as Assistant Director of Prospect Research. She has been affiliated with The Helen Brown Group since January 2014.
Heather began her career in 2002 as a prospect research coordinator for the Rocky Mountain Elk Foundation and then moved to Carroll College in 2004.
In 2005, Heather began working on her own as a freelancer and eventually started her own consulting firm, Willis Research Services, in 2007. She joined The Helen Brown Group in 2012.
Heather is a member of the Association of Professional Researchers for Advancement and the Montana Nonprofit Association.
Jennifer began her career in development at her alma mater, Wheaton College, where she was an administrative assistant for the major gifts department.
She joined The Helen Brown Group in March 2008. She earned a master's degree in library science from the Southern Connecticut State University in May 2009. Jennifer is a member of APRA and NEDRA.
Rick has been a member of the Helen Brown Group team since 2005. Prior to joining HBG, Rick was director of research at St. Paul's School in Concord, New Hampshire. Rick has worked in development since 1996, both in prospect research and major gifts fund raising. His experience includes the University of Vermont, Phillips Exeter Academy and St. Paul's School.
Rick is past president of NEDRA and is a member of and frequent volunteer for APRA.
Mandi has worked in prospect research and management since 2006. She began her development career as a research analyst in development research at City of Hope, an NCI-designated comprehensive cancer center in Los Angeles. From there, she became the manager of prospect development at Huntington Memorial Hospital, a community hospital in Pasadena, CA. Most recently, she was the associate director of prospect research and management at Occidental College, a private liberal arts college in LA.
Mandi has a BA degree in print journalism from Southern Methodist University and a master's degree of library and information science from UCLA.
She joined the Helen Brown Group in May 2019.
Kelly began her career in development in 2008 as an administrative assistant in Major Gifts at Wheaton College.
In 2010, she became a research analyst at Dana-Farber Cancer Institute in the Division of Development & Jimmy Fund as part of the prospect identification team. Kelly joined The Helen Brown Group in 2013.
She is a member of APRA and NEDRA.
Jayme began her career in development in 2008 at the Rutgers University Foundation, where she spent the next seven years, first in prospect management and then prospect research. She spent several years at Monmouth University as their senior prospect research analyst, working with the fundraising staff, university president, and top leadership. She has worked as both a volunteer and consultant for non-profits in the areas of research and writing.
She earned a bachelor of arts degree from Drew University and a master of communication and information sciences from Rutgers University. She is a member of APRA.
Jayme joined The Helen Brown Group in April 2019.
Julie has managed finances for The Helen Brown Group since its founding.
In her spare time, she is an editor for the PBS series Masterpiece at WGBH. Julie was nominated twice for an Emmy award for her work on the PBS show Zoom.
Heather began her career in development in 2001 as a prospect researcher for National Wildlife Federation (NWF). She was with NWF for more than thirteen years, including nearly five years as director of research and analytics. Heather is a former secretary of the board of directors of APRA-Metro DC.
She joined The Helen Brown Group in October 2014.
David began his career in development at The Gunnery school in northwest Connecticut in 2011, where he worked in database management and prospect research. Subsequently, he joined the College of Saint Rose as a development research analyst before leading Albany Medical Center Foundation's prospect research efforts as Associate Director of Prospect Research. He has a Bachelor's Degree in Sociology from Siena College and is a member of APRA and CASE.
Michele began her career in development in 2012 when she joined the UC Berkeley corporate and foundation relations team as a development analyst. She spent a year and a half at Cal before returning to UC Davis as a prospect analyst. She was with the prospect management and relations team at UC Davis for almost three years prior to joining the research and relationship management team at George Washington University as a Senior Prospect Analyst in 2016.
Michele received her BA in creative writing from Florida State University and her MA in higher education leadership from CSU Sacramento. She currently resides in Northern Virginia, is a member of Apra International, and serves as the social media chair for Apra Metro DC. Michele joined The Helen Brown Group in July 2018.
Angie has worked in development since 2002, partnering with a wide range of nonprofit institutions. She began her professional career at Vanderbilt University in research and prospect development.
She has also worked with a number of community nonprofits in front-line fundraising, grant-writing, and event management. Angie holds an MPA in Nonprofit Management from the Indiana University Lilly Family School of Philanthropy and a BS in Journalism from Middle Tennessee State University. She resides in Nashville, Tennessee, and is a member of AFP Nashville and APRA MidSouth, where she has been active on the executive team.
Maureen has been a part of the non-profit world since 1991. She started out in annual giving at Harvard Law School and continued her career as director of annual/special gifts at UC Santa Cruz.
In 1999 she made the switch from front-line fundraising to serve as director of prospect research/management at Bentley University and in 2001 began her role as administrator for the North American Foundation for the University of Manchester. She became part of the HBG team in September of 2011.
Helen has been a development professional since 1987. Her previous experience includes The University of North Carolina at Chapel Hill, the Albert Einstein Institution, Boston College, the Harvard School of Public Health and Northeastern University.
Currently she works with a variety of clients to establish, benchmark and re-align research departments; identify major gift prospects; and train researchers and other fundraisers through on-site and web-based training services.Helen is a former member of the board of the Association of Professional Researchers for Advancement (APRA) and is past president of the New England Development Research Association (NEDRA). In 2006 she received the NEDRA Ann Castle Award for service to the prospect research community.
Helen is Special Advisor on Fundraising to the North American Foundation for the University of Manchester and is a member of the board of directors of Factary Ltd. (Bristol, UK). She is a member of NEDRA, APRA, the Association of Independent Information Professionals (AIIP), Women In Development, the Association of Fundraising Professionals (AFP) and Researchers in Fundraising (UK).
Helen is a frequent speaker and has led seminars for a number of professional associations, including Action Planning, AFP, APRA, the Council for Advancement and Support of Education (CASE), NEDRA, RIF, the Planned Giving Council of Central Massachusetts, the Georgia Center on Nonprofits, the International Fundraising Congress and Resource Alliance.
Helen is also co-author (with Jen Filla) of the book, Prospect Research for Fundraisers (Wiley & Sons, 2013).


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Arnold Schwarzenegger donates $100,000 to 'anti-hate organization' after Charlottesville violence
By Kelcie Willis, Cox Media Group National Content Desk
Arnold Schwarzenegger is putting his money where his mouth is after seeing coverage of the violence at a white supremacist rally in Charlottesville, Virginia, Saturday.
In a statement posted on a note on his Facebook page Sunday, the former governor of California said he had been "horrified by the images of Nazis and white supremacists marching in Charlottesville and I was heartbroken that a domestic terrorist took an innocent life. My thoughts and prayers are with the families of Heather Heyer, Lt. Cullen, and Trooper-Pilot Bates." He announced he would be donating $100,000 to an "anti-hate organization."
Heather Heyer was killed after police said James Alex Fields Jr. drove into a crowd of counterprotesters at the rally.
Lt. H. Jay Cullen and Trooper-Pilot Burke M.M. Bates were killed in a helicopter crash Saturday while assisting with the incident in Charlottesville. The crash, which is under investigations, happened in a wooded area near a home. The two were the only fatalities.
"While these so-called 'white nationalists' are lucky to live in a country that defends their right to voice their awful, incorrect, hateful opinions, the rest of us must use our voices and resources to condemn hate and teach tolerance at every opportunity," Schwarzenegger's statement said.
"My message to them is simple: you will not win. Our voices are louder and stronger. There is no white America - there is only the United States of America. You were not born with these hateful views - you can change, grow, and evolve, and I suggest you start immediately."
Schwarzenegger then said he would donate $100,000 to the Simon Wiesenthal Center, a Los Angeles non profit organzation
"I'm sending $100,000 to an anti-hate organization I've worked with for decades - the Simon Wiesenthal Center, named after the great Nazi hunter who I was lucky to call a friend."
According to its website, the Simon Wiesenthal Center "confronts anti-Semitism, hate and terrorism, promotes human rights and dignity, stands with Israel, defends the safety of Jews worldwide, and teaches the lessons of the Holocaust for future generations."
In a statement Monday, the Wiesenthal Center called on President Donald Trump to "specifically condemn the extreme alt-right and white nationalists who sow seeds of hate, distrust and violence. They and all other extremists, left or right, have no place in the mainstream of our nation."
That same day, Trump denounced white supremacists, Nazis and KKK members in a prepared statement. It was two days after the violence in Charlottesville.
On Wednesday, he backtracked, returning to his initial statement Saturday in which he said "many sides" were to blame for the violence.
"I think there's blame on both sides. And I have no doubt about it," he said at a news conference Wednesday.
That initial response drew criticism from Democrats and Republicans.
Kelcie Willis, Cox Media Group National Content Desk