***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND The positive association between obesity and postmenopausal breast cancer has been attributed , in part , to the fact that estrogen , a risk factor for breast cancer , is synthesized in adipose tissue . Obesity is also associated with high levels of insulin , a known mitogen . However , no prospect i ve studies have directly assessed associations between circulating levels of insulin and /or insulin-like growth factor (IGF)-I , a related hormone , and the risk of breast cancer independent of estrogen level . METHODS We conducted a case-cohort study of incident breast cancer among nondiabetic women who were enrolled in the Women 's Health Initiative Observational Study ( WHI-OS ) , a prospect i ve cohort of 93,676 postmenopausal women .  Fasting serum sample s obtained at study entry from 835 incident breast cancer case subjects and from a subcohort of 816 r and omly chosen WHI-OS subjects were tested for levels of insulin , glucose , total IGF-I , free IGF-I , insulin-like growth factor binding protein-3 , and estradiol .  Multivariable Cox proportional hazards models were used to estimate associations between levels of the serologic factors and baseline characteristics ( including body mass index [ BMI ] ) and the risk of breast cancer . All statistical tests were two-sided . Results Insulin levels were positively associated with the risk of breast cancer ( hazard ratio [ HR ] for highest vs lowest quartile of insulin level = 1.46 , 95 % confidence interval [ CI ] = 1.00 to 2.13 , P(trend ) = .02 ) ; however , the association with insulin level varied by hormone therapy ( HT ) use ( P(interaction ) = .01 ) . In a model that controlled for multiple breast cancer risk factors including estradiol , insulin level was associated with breast cancer only among nonusers of HT ( HR for highest vs lowest quartile of insulin level = 2.40 , 95 % CI = 1.30 to 4.41 , P(trend ) < .001 ) . Obesity ( BMI > or=30 kg/m(2 ) ) was also associated with the risk of breast cancer among nonusers of HT ( HR for BMI > or=30 kg/m(2 ) vs 18.5 to < 25 kg/m(2 ) = 2.12 , 95 % CI = 1.26 to 3.58 , P(trend ) = .003 ) ; however , this association was attenuated by adjustment for insulin ( P(trend ) = .40 ) . CONCLUSION These data suggest that hyperinsulinemia is an independent risk factor for breast cancer and may have a substantial role in explaining the obesity-breast cancer relationship Objective : Hepatocyte growth factor ( HGF ) has been reported the cause of many biological events , including cell proliferation , movement , invasiveness , morphogenesis , and angiogenesis . Elevated hepatocyte growth factor content in tumor tissue was reported to predict a more aggressive biology in non – small cell lung cancer patients . However , there is still limited knowledge about the role of HGF in breast cancer . This study was design ed with the aim to eluci date the possible relationship between the preoperative circulating soluble HGF and breast cancer . Material s and Methods : One hundred twenty-four consecutive patients with invasive breast cancer undergoing surgery were prospect ively included and evaluated . Venous blood sample s were collected before the surgery . Sera were obtained by centrifugation and stored at −70 ° C until assayed . The control group consisted of 35 patients with benign breast tumor ( 20 with fibrocystic disease and 15 with fibroadenoma ) .  Serum concentrations of soluble HGF were measured by the quantitative s and wich enzyme immunoassay technique . The data on primary tumor staging , age , estrogen receptor status , lymph node status , distant metastases status , histologic grading , and tumor-node-metastasis ( TNM ) staging were review ed and recorded . Results : The mean value of serum soluble HGF in patients with invasive breast cancer was 529.05 ± 123.33 pg/mL and that of control group was 343.00± 31.03 pg/mL and the difference was significant ( P < 0.001 ) . Furthermore , there were significantly higher serum levels of soluble HGF in patients with negative estrogen receptor ( P = 0.035 ) , in patients with poorer differentiated tumor ( P < 0.001 ) , in patients with more advanced primary tumor staging ( P < 0.001 ) , in patients with more advanced lymph node status ( P < 0.001 ) , in patients with distant metastases ( P < 0.001 ) , and in patients with more advanced TNM staging ( P < 0.001 ) . In multivariate analysis by the multiple linear regression method , TNM staging ( P < 0.001 ) seemed an independent factor regarding the significant higher serum levels of soluble HGF . Conclusion : Patients with more advanced TNM staging were shown to have higher serum soluble HGF . Thus , preoperative serum soluble HGF levels might reflect the severity of invasive breast cancer and deserve further evaluation Obesity has been associated with an increased risk of postmenopausal breast cancer . Adipokines and systemic inflammation have been hypothesized to underlie this association . In a case – control study nested within the Multiethnic Cohort , conditional logistic regression was used to calculate the ORs and 95 % confidence intervals ( CI ) for postmenopausal breast cancer associated with prediagnostic levels of serum leptin , adiponectin , the leptin : adiponectin ratio , and C-reactive protein ( CRP ) . The 706 cases and 706 controls were matched on ethnicity , location ( Hawaii or Los Angeles ) , birth year , date and time of blood draw , hours fasting before blood draw , and hormone replacement therapy use at blood draw . Higher circulating levels of leptin [ ORQ4 vs. Q1 , 1.94 ( 1.37–2.75 ) ; Ptrend ≤ 0.001 ) , the leptin : adiponectin ratio [ OR , 1.91 ( 1.36–2.68 ) ; Ptrend = 0.005 ] , and CRP [ OR , 1.41 ( 1.01–1.96 ) ; Ptrend = 0.014 ] were associated with an increased risk of postmenopausal breast cancer . The positive associations for these markers remained after adjustment for body mass index ( BMI ) . No associations were detected for adiponectin . These data suggest that adipokines and systemic inflammation may be associated with the risk of postmenopausal breast cancer independently of BMI . Further prospect i ve studies examining the role of adipokines and inflammatory processes in the etiology of postmenopausal breast cancer are warranted . Cancer Prev Res ; 6(3 ) ; 188–95 . © 2013 AACR Introduction Breast cancer is the most common type of cancer seen in women in western countries . Thus , diagnostic modalities sensitive to early-stage breast cancer are needed . Antibody-based array platforms of a data -driven type , which are expected to facilitate more rapid and sensitive detection of novel biomarkers , have emerged as a direct , rapid means for profiling cancer-specific signatures using small sample s. In line with this concept , our group constructed an antibody bead array panel for 35 analytes that were selected during the discovery step . This study was aim ed at testing the performance of this 35-plex array panel in profiling signatures specific for primary non-metastatic breast cancer and validating its diagnostic utility in this independent population . Methods Thirty-five analytes were selected from more than 50 markers through screening steps using a serum bank consisting of 4,500 sample s from various types of cancer .  An antibody-bead array of 35 markers was constructed using the Luminex ™ bead array platform .  A study population consisting of 98 breast cancer patients and 96 normal subjects was analysed using this panel . Multivariate classification algorithms were used to find discriminating biomarkers and vali date d with another independent population of 90 breast cancer and 79 healthy controls . Results Serum concentrations of epidermal growth factor , soluble CD40-lig and and proapolipoprotein A1 were increased in breast cancer patients . High-molecular-weight-kininogen , apolipoprotein A1 , soluble vascular cell adhesion molecule-1 , plasminogen activator inhibitor-1 , vitamin-D binding protein and vitronectin were decreased in the cancer group . Multivariate classification algorithms distinguished breast cancer patients from the normal population with high accuracy ( 91.8 % with r and om forest , 91.5 % with support vector machine , 87.6 % with linear discriminant analysis ) . Combinatorial markers also detected breast cancer at an early stage with greater sensitivity . Conclusions The current study demonstrated the usefulness of the antibody-bead array approach in finding signatures specific for primary non-metastatic breast cancer and illustrated the potential for early , high sensitivity detection of breast cancer . Further validation is required before array-based technology is used routinely for early detection of breast cancer The cytokines tumor necrosis factor-alpha ( TNF-alpha ) , soluble TNF receptors p55 and p75 , and interleukin 6 ( IL-6 ) are involved in host defense against several microbiological agents , in the process of inflammation and also in body weight regulation . In the present study , we sought to assess the influence of age , gender , smoking , and body mass index on plasma levels of TNF-alpha , TNF receptors , and IL-6  in more than 550 adult subjects r and omly selected from the Bavarian population . None of the cytokine parameters had a normal distribution and all distributions were significantly skewed . The cytokine plasma levels investigated increased significantly with age , while gender had a relatively weaker influence on the plasma levels . Plasma levels of TNF-alpha , TNF receptors , and IL-6 correlated significantly with the BMI . The study provides insights into factors influencing the cytokine levels investigated in a r and omly chosen study sample The aim of our study was to determine whether adipocyte-derived hormones leptin , adiponectin and resistin contribute to the improvement of insulin sensitivity after very-low calorie diet ( VLCD ) . Therefore , serum levels of these hormones were measured in fourteen obese females before and after three weeks VLCD and in seventeen age- and sex-matched healthy controls .  Body mass index , HOMA index , serum insulin and leptin levels in obese women before VLCD were significantly higher than in control group ( BMI 48.01+/-2.02 vs. 21.38+/-0.42 kg/m(2 ) , HOMA 10.72+/-2.03 vs. 4.69+/-0.42 , insulin 38.63+/-5.10 vs. 18.76+/-1.90 microIU/ml , leptin 77.87+/-8.98 vs. 8.82+/-1.52 ng/ml ) . In contrast , serum adiponectin and soluble leptin receptors levels were significantly lower in obese women before VLCD than in the control group . No differences were found in serum glucose and resistin levels between the obese group before VLCD and the control group . VLCD significantly decreased BMI , HOMA index , serum glucose , insulin and leptin levels and increased soluble leptin receptor levels . The changes in serum adiponectin and resistin levels in obese women after VLCD did not reach statistical significance . We conclude that leptin and soluble leptin receptor levels were affected by VLCD while adiponectin and resistin concentrations were not . Therefore , other mechanisms rather than changes in the endocrine function of the adipose tissue are probably involved in the VLCD-induced improvement of insulin sensitivity OBJECTIVE Obese patients demonstrate a variety of biochemical , metabolic , and pulmonary abnormalities . Inflammatory mediators such as tumor necrosis factor-alpha and interleukin-6 ( IL-6 ) may have a direct effect on glucose and lipid metabolism . Hypoxemia in itself induces release of IL-6 . The aim of this study was to examine the relationship between IL-6 levels in healthy volunteers ( control group ) and three different groups of obese patients : patients without obstructive sleep apnea syndrome ( OSAS ) , patients with OSAS , and patients with obesity hypoventilation syndrome ( OHS ) ( daytime baseline oxygen saturation of < 93 % ) . RESEARCH METHODS AND PROCEDURES We measured  serum IL-6 levels  in 25 obese patients ( body mass index of > 35 kg/m2 ) and 12 healthy women . RESULTS The results demonstrate statistically significant differences in serum IL-6 levels between the control group ( 1.28 + /- 0.85 pg/mL ) and obese patients without OSAS ( 7.69 + /- 5.06 pg/mL , p < 0.05 ) and with OSAS ( 5.58 + /- 0.37 pg/mL , p < 0.0005 ) . In the patients with OHS , IL-6 concentrations were highest ( 43.13 + /- 24.27 pg/mL ) . DISCUSSION We conclude that serum IL-6 is increased in obese patients . The highest IL-6 levels were found in the patients with OHS Obesity is considered the most important risk and prognostic factor for estrogen-dependent breast cancer in postmenopausal women . Adipokines , in particular lept 
    Output:
    
Decreased concentrations of adiponectin , and increased concentrations of leptin , IL-6 , IL-8 , TNF-α , resistin and visfatin were significantly associated with risk of breast cancer .
Adipokine levels were strongly associated with breast cancer among Asian women as compared to non-Asian women .
Our results might explain the relationship of obesity , adipokine levels and risk of breast cancer , especially in Asian women