Secreted frizzled-related protein 2 (SFRP2) expression promotes lesion proliferation via canonical WNT signaling and indicates lesion borders in extraovarian endometriosis.

STUDY QUESTION: What is the role of SFRP2 in endometriosis? SUMMARY ANSWER: SFRP2 acts as a canonical WNT/CTNNB1 signaling agonist in endometriosis, regulating endometriosis lesion growth and indicating endometriosis lesion borders together with CTNNB1 (also known as beta catenin). WHAT IS KNOWN ALREADY: Endometriosis is a common, chronic disease that affects women of reproductive age, causing pain and infertility, and has significant economic impact on national health systems. Despite extensive research, the pathogenesis of endometriosis is poorly understood, and targeted medical treatments are lacking. WNT signaling is dysregulated in various human diseases, but its role in extraovarian endometriosis has not been fully elucidated. STUDY DESIGN, SIZE, DURATION: We evaluated the significance of WNT signaling, and especially secreted frizzled-related protein 2 (SFRP2), in extraovarian endometriosis, including peritoneal and deep lesions. The study design was based on a cohort of clinical samples collected by laparoscopy or curettage and questionnaire data from healthy controls and endometriosis patients. PARTICIPANTS/MATERIALS, SETTING, METHODS: Global gene expression analysis in human endometrium (n = 104) and endometriosis (n = 177) specimens from 47 healthy controls and 103 endometriosis patients was followed by bioinformatics and supportive qPCR analyses. Immunohistochemistry, Western blotting, primary cell culture and siRNA knockdown approaches were used to validate the findings. MAIN RESULTS AND THE ROLE OF CHANCE: Among the 220 WNT signaling and CTNNB1 target genes analysed, 184 genes showed differential expression in extraovarian endometriosis (P < 0.05) compared with endometrium tissue, including SFRP2 and CTNNB1. Menstrual cycle-dependent regulation of WNT genes observed in the endometrium was lost in endometriosis lesions, as shown by hierarchical clustering. Immunohistochemical analysis indicated that SFRP2 and CTNNB1 are novel endometriosis lesion border markers, complementing immunostaining for the known marker CD10 (also known as MME). SFRP2 and CTNNB1 localized similarly in both the epithelium and stroma of extraovarian endometriosis tissue, and interestingly, both also indicated an additional distant lesion border, suggesting that WNT signaling is altered in the endometriosis stroma beyond the primary border indicated by the known marker CD10. SFRP2 expression was positively associated with pain symptoms experienced by patients (P < 0.05), and functional loss of SFRP2 in extraovarian endometriosis primary cell cultures resulted in decreased cell proliferation (P < 0.05) associated with reduced CTNNB1 protein expression (P = 0.05). LIMITATIONS REASONS FOR CAUTION: SFRP2 and CTNNB1 improved extraovarian endometriosis lesion border detection in a relatively small cohort (n = 20), although larger studies with different endometriosis subtypes in variable cycle phases and under hormonal medication are required. WIDER IMPLICATIONS OF THE FINDINGS: The highly expressed SFRP2 and CTNNB1 improve endometriosis lesion border detection, which can have clinical implications for better visualization of endometriosis lesions over CD10. Furthermore, SFRP2 acts as a canonical WNT/CTNNB1 signaling agonist in endometriosis and positively regulates endometriosis lesion growth, suggesting that the WNT pathway may be an important therapeutic target for endometriosis. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by the Academy of Finland and by Tekes: Finnish Funding Agency for Innovation. The authors have no conflict of interest to declare.

Prevalence of Pain Symptoms Suggestive of Endometriosis Among Finnish Adolescent Girls (TEENMAPS Study).

STUDY OBJECTIVE: To evaluate the prevalence of pain symptoms suggestive of endometriosis among adolescent girls aged 15-19 years. DESIGN: Cross-sectional study. SETTING: University hospital. PARTICIPANTS: Adolescent girls aged 15-19 years attending elementary school, high school, or vocational institute at 3 cities in Southwest Finland in 2010-2011. INTERVENTIONS: The school nurses distributed a detailed questionnaire to 2582 girls who were attending school at the time of the study. Completion of the questionnaire was voluntary and anonymous. MAIN OUTCOME MEASURES: Prevalence and severity of dysmenorrhea, acyclic abdominal pain, dyspareunia, dyschezia, and dysuria. Severity was evaluated with an 11-point numerical rating scale (NRS). RESULTS: A total of 1103 eligible answers were analyzed. The prevalence of dysmenorrhea was 68% (738/1092) with mean NRS of 7.0 (SD = 2.0). Acyclic abdominal pain, dyspareunia, dyschezia, and dysuria were less frequent (19% [207/1085], 12% [53/458], 8% [87/1088] and 5% [50/1084], respectively). The prevalence of severe dysmenorrhea (NRS 8-10) was 33% (355/1089). Severe dysmenorrhea was associated with increased risk of concurrent acyclic abdominal pain (odds ratio [OR] = 2.7; 95% confidence interval [CI], 2.0-3.6), dyschezia (OR = 2.5; 95% CI, 1.6-3.9), and regular absenteeism from school or hobbies (OR = 10.0; 95% CI, 4.2-23.6). Using different criteria, 2%-10% (21-106/1103) of all girls could be identified as having symptoms suggestive of endometriosis. Five percent of girls (n = 53/1103) had severe dysmenorrhea, used oral contraceptive pills, and reported inadequate relief from pain medication. CONCLUSION: One-third (355/1089) of 15- to 19-year-old girls had severe menstrual pain and 14% (49/355) of them were regularly absent from school or hobbies. Five percent of all teenage girls (53/1103) were poor responders to conventional therapy for primary dysmenorrhea.

Serum HE4 concentration is not dependent on menstrual cycle or hormonal treatment among endometriosis patients and healthy premenopausal women.

OBJECTIVE: Human epididymal secretory protein E4 (HE4) is a new promising tumor marker developed for the diagnostics and follow up of ovarian cancer. It has yet to become widely accepted in clinical practice, and its biological properties have not been inclusively studied. The aim of this study was to investigate whether serum HE4 concentration varies within the normal menstrual cycle and whether common gynecological hormonal treatments have an effect on HE4 values. METHODS: Our study population consisted of 180 women, including 126 endometriosis patients and 54 healthy women. We measured their serum HE4 and CA125 concentrations and evaluated the effect of the menstrual cycle and the possible hormonal medication on these marker concentrations. RESULTS: We found no significant variation in serum HE4 concentrations in samples taken at different phases of the menstrual cycle. The median HE4 concentrations in proliferative, secretory and menstrual phase were 41.5, 45.1 and 35.3 pM in healthy women, and 43.4, 44.3 and 43.0 pM in endometriosis patients, respectively. The use of combined estrogen and progestin contraceptives did not affect serum HE4 levels significantly. CONCLUSIONS: The present study shows that the HE4 measurement in healthy premenopausal women as well as in women with endometriosis can be carried out at any phase of the menstrual cycle, and irrespective of hormonal medication, extending the benefits of HE4 use in clinical practice.

Serum HE4 concentration differentiates malignant ovarian tumours from ovarian endometriotic cysts.

Human epididymal secretory protein E4 (HE4, also known as WAP four-disulphide core domain protein 2) is a new promising biomarker for ovarian cancer but its specificity against ovarian endometriotic cysts is only superficially known. We, thus, analysed serum HE4 concentrations together with a tumour marker CA125 in serum samples of women diagnosed with various types of endometriosis, endometrial cancer or ovarian cancer, and in samples from healthy controls. The mean serum concentration of HE4 was significantly higher in serum samples of patients with both endometrial (99.2 pM, P<0.001) and ovarian (1125.4 pM, P<0.001) cancer but not with ovarian endometriomas (46.0 pM) or other types of endometriosis (45.5 pM) as compared with healthy controls (40.5 pM). The serum CA125 concentrations were elevated in patients with ovarian cancer, advanced endometriosis with peritoneal or deep lesions, or ovarian endometriomas, but not in the patients with endometrial cancer. The microarray results revealed that the mRNA expression of the genes encoding HE4 and CA125 reflected the serum protein concentrations. Taken together, measuring both HE4 and CA125 serum concentrations increases the accuracy of ovarian cancer diagnosis and provides valuable information to discriminate ovarian tumours from ovarian endometriotic cysts.