title: Calpain5 expression is decreased in endometriosis and regulated by HOXA10 in human endometrial cells.
abstract: Calpains have been implicated in the regulation of apoptosis. Here, we identified Calpain5 as a target of HOXA10 transcriptional regulation in endometrial cells as well as its aberrant regulation in endometriosis. Histologically confirmed biopsies of endometriosis were obtained from 20 women. Eutopic endometrium was collected by endometrial biopsy from 30 controls and from the 20 subjects with endometriosis. First trimester decidual samples were obtained from five subjects at the time of pregnancy termination. Immunohistochemistry was used to identify Calpain5 expression. Calpain5 was expressed in endometrial stromal and glandular cells throughout the menstrual cycle and in decidua. Calpain5 protein expression was decreased in both stromal and glandular cells from women with endometriosis compared with that of fertile controls. Human endometrial stromal and epithelial cell lines were transfected with pcDNA/HOXA10, HOXA10 siRNA or respective controls. Quantitative real-time RT-PCR was performed to determine expression of HOXA10 and Calpain5 in each group. Transfection of HESC cells with an HOXA10 expression construct led to increased Calpain5 expression, whereas transfection with siRNA resulted in decreased expression. In conclusion, Calpain5 expression is regulated by HOXA10. Calpain5 expression was decreased in endometriosis likely as a result of decreased HOXA10 expression. Decreased apoptosis in endometrial cells may promote the development of endometriosis through a pathway involving HOXA10, Calpain5 and caspase.
authors.affiliation: Division of Reproductive Endocrinology and Infertility, Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA.
authors.forename: Ivan
authors.initials: I
authors.lastname: Penna
authors.forename: Hongling
authors.initials: H
authors.lastname: Du
authors.forename: Rui
authors.initials: R
authors.lastname: Ferriani
authors.forename: Hugh S
authors.initials: HS
authors.lastname: Taylor
mesh_terms: D000328:Adult; D015153:Blotting, Western; D002154:Calpain / Q000378:metabolism* / Q000502:physiology; D002460:Cell Line; D045744:Cell Line, Tumor; D003656:Decidua / Q000378:metabolism; D004715:Endometriosis / Q000378:metabolism*; D004717:Endometrium / Q000166:cytology / Q000378:metabolism*; D005260:Female; D000080905:Homeobox A10 Proteins; D018398:Homeodomain Proteins / Q000235:genetics / Q000502:physiology; D006801:Humans; D007150:Immunohistochemistry; D011247:Pregnancy; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D000080905:Homeobox A10 Proteins; D018398:Homeodomain Proteins; C069634:HOXA10 protein, human; D002154:Calpain; C494426:Capn5 protein, human