The expression levels of stem cell markers importin13, c-kit, CD146, and telomerase are decreased in endometrial polyps

BACKGROUND To investigate the expression levels of importin13 (IPO13), c-kit, CD146, telomerase, caspase-3, bcl-2 and bax in endometrial polyps (EPs). MATERIAL/METHODS We detected the mRNA expression levels of IPO13, c-kit, bcl-2 and bax in endometrial polyps (EPs) using real-time PCR. We detected the protein expression levels of IPO13, telomerase, CD146, caspase-3, bcl-2 and bax in EPs using S-P (Streptavidin-Peroxidase) immunohistochemistry. Western blotting was performed to determine the levels of importin13 and bcl-2 proteins in EPs. RESULTS The expression levels of IPO13, c-kit, telomerase, caspase3, and bax were lower in the EP tissue compared to normal endometrial tissue during the proliferation and secretion phases of the menstrual cycle (p<0.05). The expression of CD146 was decreased in the EP tissue compared to the normal endometrial tissue during the proliferation phase of the menstrual cycle (p<0.05). The expression of bcl-2 was increased in the EP tissue compared to the normal endometrial tissue during the proliferation and secretion phases of the menstrual cycle (p<0.05). CONCLUSIONS The expression levels of IPO13, c-kit, telomerase, caspase3, and bax were decreased; however, the expression of bcl-2 was increased in the EP tissue compared to the normal endometrial tissue. These findings suggest that the development of EPs is associated with the deregulated activities of the endometrial stem/progenitor cells and the decreased apoptosis of endometrial cells, with the latter being the major factor involved in the development of EPs.