title: Progesterone-induced cyclin G1 inhibits the proliferation of endometrial epithelial cell and its possible molecular mechanism.
abstract: Under normal conditions, progesterone inhi-bits the estrogen-induced proliferation of endometrial epithelium. Our previous studies have shown that cyclin G1 was progesterone-dependent in mouse endometrial epithelium at peri-implantation, and exogenous cyclin G1 suppressed the proliferation of endometrial cancer cells. The objectives of this study are to determine whether cyclin G1, as a negative regulator of the cell cycle, is involved in the antiproliferative action of progesterone on endometrial epithelial cells, and to explore the possible molecular mechanism of cyclin G1 inhibition. The siRNA-mediated elimination of cyclin G1 attenuated the antiproliferative action of progesterone on endometrial epithelial cells. Immunoprecipitation showed that progesterone-induced cyclin G1 could interact with PP2A to mediate its phosphatase activity. The block of PP2A activity also attenuated the antiproliferative action of progesterone on endometrial epithelial cells and increased the phosphorylated Rb. In conclusion, progesterone-induced cyclin G1 mediates the inhibitory effect of progesterone on endometrial epithelial cell proliferation possibly through the recruitment of PP2A to dephosphorylate Rb.
authors.affiliation: Department of Physiology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, P. R. China.
authors.forename: D-z
authors.initials: DZ
authors.lastname: Yuan
authors.affiliation: Department of Physiology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, P. R. China.
authors.forename: X-l
authors.initials: XL
authors.lastname: Ding
authors.affiliation: Department of Physiology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, P. R. China.
authors.forename: H-l
authors.initials: HL
authors.lastname: Yu
authors.affiliation: Department of Physiology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, P. R. China.
authors.forename: Z
authors.initials: Z
authors.lastname: Cheng
authors.affiliation: Department of Physiology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, P. R. China.
authors.forename: X-r
authors.initials: XR
authors.lastname: Tang
authors.affiliation: Department of Physiology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, P. R. China.
authors.forename: Y-p
authors.initials: YP
authors.lastname: He
authors.affiliation: Department of Physiology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, P. R. China.
authors.forename: J-h
authors.initials: JH
authors.lastname: Zhang
authors.affiliation: Department of Obstetrics and Gynecology, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: L J
authors.initials: LJ
authors.lastname: Blok
authors.affiliation: Department of Obstetrics and Gynecology, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: P
authors.initials: P
authors.lastname: Hanifi-Moghaddam
authors.affiliation: Department of Obstetrics and Gynecology, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: C W
authors.initials: CW
authors.lastname: Burger
authors.affiliation: Department of Physiology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, P. R. China.
authors.forename: L-M
authors.initials: LM
authors.lastname: Yue
mesh_terms: D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D056766:Cyclin G1 / Q000378:metabolism*; D004717:Endometrium / Q000166:cytology*; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D005260:Female; D006801:Humans; D051379:Mice; D019319:Okadaic Acid / Q000494:pharmacology; D011374:Progesterone / Q000494:pharmacology*; D011485:Protein Binding / Q000187:drug effects; D054648:Protein Phosphatase 2 / Q000378:metabolism; D034741:RNA, Small Interfering / Q000378:metabolism
chemical_list: D056766:Cyclin G1; D034741:RNA, Small Interfering; D019319:Okadaic Acid; D011374:Progesterone; D054648:Protein Phosphatase 2