Interactions between galectin-3 and integrinbeta3 in regulating endometrial cell proliferation and adhesion.
BACKGROUND
Galectin-3 (gal-3) is a beta-galactoside-binding protein which can be detected in endometrium. The study was designed to investigate synergism of gal-3 and integrinbeta3 in endometrial cell proliferation and adhesion in an in vitro model of endometrial receptivity.


METHODS
The RL95-2 cell line was employed as an in vitro model for receptive endometrium. Cells transfected with gal-3 siRNA or treated with exogenous gal-3 were incubated with or without function-blocking integrinbeta1/3 antibody for evaluating synergism of gal-3 and integrins on cell proliferation and adhesion. Proliferation was measured by BrdU incorporation, and adhesion to fibronectin (FN) was determined by an adhesion assay. Integrin expression was analyzed by Flow Cytometry and western blots. Bewo spheroids were co-cultured with the RL95-2 monolayer to mimic the blastocyst-endometrial interaction, and colocalization of gal-3, integrinbeta3 and FN at the interface was observed by confocal microscopy.


RESULTS
The knock-down of gal-3 inhibited RL95-2 cell proliferation and adhesion. However, a reduction of proliferation and adhesion was also observed in presence of exogenous gal-3, and this was further reduced by a functional block to integrinbeta3. Moreover, gal-3 knock-down significantly increased integrinbeta3 expression, however, the colocalization of integrinbeta3 and FN was not increased. As expected, the colocalization of integrinbeta3 was decreased with the knock-down of gal-3.


CONCLUSIONS
This study has provided an in vitro model for the complex interactions between gal-3 and integrinbeta3 in the regulation of endometrial cell proliferation and adhesion.
Lei
Cai-Xia
CX
Department of Reproductive Endocrinology, Obstetrics & Gynecology Hospital, Fudan University, Shanghai 200011, China.
Zhang
Wei
W
Zhou
Jian-Ping
JP
Liu
Yin-Kun
YK
D002448:Cell Adhesion; D002460:Cell Line; D049109:Cell Proliferation; D004717:Endometrium / Q000166:cytology / Q000378:metabolism*; D005260:Female; D005353:Fibronectins / Q000378:metabolism; D037502:Galectin 3 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D006801:Humans; D039661:Integrin beta3 / Q000378:metabolism*; D034622:RNA Interference
D005353:Fibronectins; D037502:Galectin 3; D039661:Integrin beta3