***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: OBJECTIVE To eluci date the potential mechanisms involved in the physiopathology of endometriosis . We analyzed the differential gene expression profiles of eutopic and ectopic tissues from women with endometriosis . DESIGN Prospect i ve laboratory study . SETTING University hospital . PATIENT(S ) Seventeen patients in whom endometriosis was diagnosed and 11 healthy fertile women . INTERVENTION(S ) Endometrial biopsy specimens from the endometrium of healthy women without endometriosis and from the eutopic and ectopic endometrium tissues of patients with endometriosis were obtained in the early proliferative phase of the menstrual cycle . MAIN OUTCOME MEASURE(S ) Six paired sample s of eutopic and ectopic tissue were analyzed by subtractive hybridization .  To evaluate the expression of genes found by rapid subtraction hybridization methods , we measured CTGF , SPARC , MYC , MMP , and IGFBP1 genes by real-time polymerase chain reaction in all sample s. RESULT ( S ) This study identified 291 deregulated genes in the endometriotic lesions . Significant expression differences were obtained for SPARC , MYC , and IGFBP1 in the peritoneal lesions and for MMP3 in the ovarian endometriomas . Additionally , significant differences were obtained for SPARC and IGFBP1 between the peritoneal and ovarian lesions . No significant differences were found for the studied genes between the control and the eutopic endometrium . CONCLUSION ( S ) This study identified 291 genes with differential expression in endometriotic lesions . The deregulation of the SPARC , MYC , MMP3 , and IGFBPI genes may be responsible for the loss of cellular homeostasis in endometriotic lesions To determine the value of  leukemia inhibitory factor ( LIF ) assessment for predicting the reproductive outcome OBJECTIVE To analyze the expression of the glycodelin gene to better underst and the molecular environment of endometriotic lesions and to eluci date the potential mechanisms that underlie the complex physiopathology of endometriosis . DESIGN Prospect i ve laboratory study . SETTING University hospital . PATIENT(S ) Eleven healthy fertile women and 17 patients with endometriosis in the early proliferative phase of the menstrual cycle . INTERVENTION(S ) Endometrial biopsy specimens were obtained from the endometrium of healthy women without endometriosis ( controls ) and from eutopic and ectopic endometrium tissues ( pelvic and ovarian endometriotic implants ) of endometriosis patients . MAIN OUTCOME MEASURE(S ) The glycodelin relative expression level by real-time polymerase chain reaction ( PCR ) analysis . RESULT ( S ) The glycodelin down-regulation found in the endometriotic lesions was 332.26 and 123.17-fold lower , respectively , when compared with the eutopic tissue and the control endometrium . CONCLUSION ( S ) Glycodelin may be one of the molecules that contributes to the loss of cellular homeostasis in endometriotic lesions OBJECTIVE To test whether hemoglobin may accumulate in the peritoneal cavity in case of endometriosis and to assess whether heme oxygenases ( HO ) , detoxifying heme , are expressed in ectopic endometrium and peritoneal cells . DESIGN Prospect i ve study involving patients with and without endometriosis . SETTING Department of gynecology in a university hospital . PATIENT(S ) Seventy-six patients undergoing laparoscopy for tubal sterilization or infertility and /or pelvic pain . INTERVENTION(S ) Collection of peritoneal fluid ( PF ) , blood sample s , and biopsies from endometrium and peritoneum . MAIN OUTCOME MEASURE(S ) Measurement of free hemoglobin and its byproduct , total and direct bilirubin , in serum and PF and analysis of HO-1 and HO-2 expression in biopsies by reverse transcription polymerase chain reaction and semiquantitative immunohistochemistry . RESULT ( S ) Higher levels of hemoglobin were found in the PF of patients with endometriosis . There was no concomitant increase in bilirubin concentrations in the PF , and HO-1 was poorly expressed in peritoneal mesothelium and macrophages . Heme oxygenase-1 and HO-2 were strongly expressed in ectopic endometrium , especially in red lesions . CONCLUSION ( S ) Our results suggest that heme may be involved in the pathogenesis and /or development of endometriosis and that the HO system , although expressed , might be insufficient to detoxify heme in women with endometriosis BACKGROUND The aim of our study was to test the hypothesis that multiple-sensory small-diameter nerve fibres are present in a higher density in endometrium from patients with endometriosis when compared with women with a normal pelvis , enabling the development of a semi-invasive diagnostic test for minimal-mild endometriosis . METHODS Secretory phase endometrium sample s ( n = 40 ) , obtained from women with laparoscopically/histologically confirmed minimal-mild endometriosis ( n = 20 ) and from women with a normal pelvis ( n = 20 ) were selected from the biobank at the Leuven University Fertility Centre . Immunohistochemistry was performed to localize neural markers for sensory C , Adelta , adrenergic and cholinergic nerve fibres in the functional layer of the endometrium . Sections were immunostained with anti-human protein gene product 9.5 ( PGP9.5 ) , anti-neurofilament protein , anti-substance P ( SP ) , anti-vasoactive intestinal peptide ( VIP ) , anti-neuropeptide Y and anti-calcitonine gene-related polypeptide . Statistical analysis was done using the Mann-Whitney U-test , receiver operator characteristic analysis , stepwise logistic regression and least-squares support vector machines . RESULTS The density of small nerve fibres was approximately 14 times higher in endometrium from patients with minimal-mild endometriosis ( 1.96 + /- 2.73 ) when compared with women with a normal pelvis ( 0.14 + /- 0.46 , P < 0.0001 ) . CONCLUSIONS The combined analysis of neural markers PGP9.5 , VIP and SP could predict the presence of minimal-mild endometriosis with 95 % sensitivity , 100 % specificity and 97.5 % accuracy . To confirm our findings , prospect i ve studies are required BACKGROUND In order to test our hypothesis that endometriosis is associated with abnormal expression of telomerase and telomere lengthening in endometrium , we assessed endometrial expression of the human telomerase enzyme and telomere length ( TL ) . METHODS This prospect i ve pilot study , included 29 women with symptomatic , surgically diagnosed endometriosis ( Group 1 ) and 27 healthy , fertile , symptom-free women without endometriosis ( Group 2 , confirmed by laparoscopy ) .  Seventeen women in Group 1 and 15 women in Group 2 had endometrial biopsies taken on Day 21 + /- 2 of the cycle . A further 12 women in each group were biopsied on Day 26 + /- 2 . Telomerase and estrogen receptor beta ( ERbeta ) expression was evaluated by immunohistochemistry . Mean TL was determined by quantitative PCR . RESULTS The endometria of fertile healthy women showed either weak or no telomerase immunoreactivity throughout the luteal phase . Immunostaining for telomerase was significantly increased during the implantation window and the premenstrual endometria of women with endometriosis ( P < 0.0001 ) . This was associated with a loss of stromal and vascular ERbeta immunostaining ( P < 0.05 ) . The mean TL were significantly longer in endometria of women with endometriosis during the implantation window ( P = 0.005 ) , indicating the biological relevance of our novel finding of telomerase in benign endometrium . There was positive correlation of the circulating estradiol with peripheral blood TL in women . CONCLUSIONS We speculate that aberrant endometrial expression of telomerase mediates alterations in cell fate that enhance proliferation , contributing to the pathogenesis of endometriosis OBJECTIVE To investigate mRNA expression of aromatase and 17beta-hydroxysteroid dehydrogenase type 2 ( 17betaHSD2 ) in epithelial and stromal cells from eutopic and ectopic endometrium of patients with deep endometriosis . DESIGN Prospect i ve study . SETTING University hospital . PATIENT(S ) Patients with deep endometriosis and fertile women with macroscopically normal pelvic cavities . INTERVENTION(S ) During surgery , 30 endometrial and 16 endometriotic sample s were obtained from 30 patients with deep endometriosis . Control endometrial sample s were obtained from 24 fertile women with macroscopically normal pelvic cavities who underwent laparoscopic tubal ligation or reversal of tubal sterilization .  Epithelial cells and stromal cells from endometrial or endometriotic tissues were microdissected using laser capture microdissection . MAIN OUTCOME MEASURE(S ) Expression levels of aromatase and 17betaHSD2 mRNA in microdissected epithelial and stromal cells were determined using quantitative real-time reverse transcriptase polymerase chain reaction . RESULT ( S ) Aromatase mRNA expression was significantly higher in epithelial cells than in stromal cells in both eutopic and ectopic endometrium obtained from endometriosis patients . In the ectopic endometrium of 8 patients ( 8/16 , 50 % ) , 17betaHSD2 expression was not detected in either epithelial or stromal cells . In eutopic endometrium from endometriosis patients , 17betaHSD2 expression in epithelial cells was significantly increased during the early , middle , and late secretory phases compared with the late proliferative phase , whereas no significant cyclical difference was detected in control endometrium . CONCLUSION ( S ) Local estrogen concentration may be much higher in epithelial cells than in stromal cells in deep endometriotic tissue OBJECTIVE To determine the distribution of catalase in eutopic and ectopic endometria in patients with endometriosis or adenomyosis . DESIGN Retrospective r and omized study . SETTING Department of obstetrics and gynecology in a university hospital . PATIENT(S ) Thirty-three patients with endometriosis , 36 with adenomyosis , and 47 fertile controls ( total , 116 women ) . MAIN OUTCOME MEASURE(S ) Semiquantitative immunostaining of endometrial cells obtained by biopsy sampling , followed by calculation of an evaluation nomogram score . RESULT ( S ) The score of catalase in the gl and ular epithelium of controls group fluctuated during the menstrual cycle ; it was lowest in the early proliferative phase and peaked in the late secretory phase . In patients with endometriosis , catalase scores did not fluctuate during the cycle , and scores were high compared with controls throughout the menstrual cycle . Catalase scores did not vary in patients with adenomyosis , and scores in this group were consistently higher than those in patients with endometriosis throughout the cycle . CONCLUSION ( S ) Abnormal expression of catalase in the eutopic and ectopic endometrium strongly suggests pathologic involvement of free radicals in endometriosis and adenomyosis OBJECTIVE To evaluate the effects of administering combination oral contraceptives ( COCs ) to patients with endometriosis on the regulation of cell growth in the eutopic endometrium . DESIGN Prospect i ve study . SETTING Research institute and clinical fertility center . PATIENT(S ) Thirteen women with untreated endometriosis and 13 controls . INTERVENTION(S ) Biopsy specimens of the eutopic endometrium were obtained from all subjects . Apoptosis , cell proliferation , and Bcl-2 and Bax expression were examined at the epithelial and stromal levels in the eutopic endometrium from patients with endometriosis before and after 30 days of daily exposure to COCs and from controls . MAIN OUTCOME MEASURE(S ) Apoptotic cells were detected by using the dUTP nick-end labeling assay ; Ki-67 , Bcl-2 , and Bax expressions were assessed by using immunohistochemical techniques . RESULT ( S ) After exposure to COCs , apoptosis was significantly increased in the eutopic endometrium compared with before COC administration , both at epithelial and stromal levels . Cell proliferation was significantly lowered by COCs . CONCLUSION ( S ) COCs showed a positive effect on patients with endometriosis by down-regulating cell proliferation and enhancing apoptosis in the eutopic endometrium OBJECTIVE To examine differential messenger RNA ( mRNA ) expression of relevant cytokines , metalloproteases , growth and adhesion factors in endometrium and peritoneum from women with endometriosis when compared with women without the disease during menstrual and luteal phases of the cycle . DESIGN Patients with endometriosis were compared with control patients . SETTING University hospital . PATIENT(S ) A total of 35 patients ( 20 patients during the luteal phase and 15 patients during the menstrual phase ) were selected for this study on the basis of cycle phase and presence or absence of endometriosis . INTERVENTION(S ) In this 
    Output:
    
This systematic review identified several reports of endometrial differences which have the potential to be biomarkers of endometriosis .