Description
The side population (SP), recently identified in several normal tissues and in a variety of tumors, may comprise cells endowed with stem cell features. In this study, we investigated the presence of SP in epithelial ovarian cancer (EOC) and found it in 4 out of 6 primary cultures from xenotransplants, as well as in 9 out of 25 clinical samples analyzed. SP cells from one xenograft bearing a large SP fraction were characterized in detail and they were capable of recreate the full repertoire of cancer cell populations observed in the parent tumor. Moreover, SP cells had higher proliferation rates, were much less apoptotic compared to non-SP cells, and generated tumors more rapidly than non-SP cells.