Enhanced differentiation and clonogenicity of human endometrial polyp stem cells

Endometrial polyps arise from endometrial overgrowth and may cause intermenstrual bleeding, irregular bleeding, and menorrhagia. In this study, endometrial polyps were harvested from hysterectomized specimens from 6 female patients not on hormone therapy. Endometrial polyp mesenchymal stem cells (EPMSCs) were isolated and characterized. Selected cells were spindle-shaped, and expressed surface markers CD90 and CD146. The EPMSCs proliferated actively in vitro. A colony-forming study demonstrates that EPMSCs had a colony-generating capacity. When cultured in a defined medium, EPMSCs can differentiate to osteoblast-, adipocyte-, and neuron-like cells. No telomerase reverse transcriptase (TERT) expression was noted. Experimental results demonstrate that EPMSCs are a population of mesenchymal progenitor cells existing in human endometrial polyps that are capable of proliferation, differentiation, and colonogenicity exceeding that of bone marrow stem cells and endometrial stromal cells. These EPMSCs may be an alternative resource of adult stem cells for future regenerative therapy.