Ovarian tumor initiating cell populations persist following paclitaxel and carboplatin chemotherapy treatment in vivo

Development of recurrent platinum resistant disease following chemotherapy presents a challenge in managing ovarian cancer. Using tumors derived from genetically defined mouse ovarian cancer cells, we investigated the stem cell properties of residual cells post-chemotherapy. Utilizing CD133 and Sca-1 as markers of candidate tumor initiating cells (TIC), we determined that the relative levels of CD133(+) and sca-1(+) cells were unaltered following chemotherapy. CD133(+) and Sca-1(+) cells exhibited increased stem cell-related gene expression, were enriched in G(0)/G(1)-early S phase and exhibited increased tumor initiating capacity, giving rise to heterogeneous tumors. Our findings suggest that residual TICs may contribute to recurrent disease. (C) 2013 Elsevier Ireland Ltd. All rights reserved.