Purpose of investigation: Presence of subset of small population of cancer stem like cells called “Side population” (SP) cells, which are responsible for multi-drug resistance and cancer relapse. The present study was designed to reveal the possible link between elevated dysadherin and drug resistance of SP cells from high-grade ovarian cancer.
Materials and methods: The cancer samples were analysed for presence of SP cells by fluorescenceactivated cell sorting method (FACs). By siRNA technology, the expression of dysadherin in SP cells was compromised and therefore we compared the extent of drug and apoptosis sensitivity of SP cells.
Results: By FACS, we have identified 3.3% of side population cells in ovarian cancer. Further, the sorted SP cells showed enhanced expression of dysadherin, ABCG2 (ABC transporter), stem cell markers such as CD133, Oct-4, and EpCAM which are responsible for multi-drug resistance and maintenance of selfrenewal of SP cells. In addition, we showed that siRNA transfected SP cells, showed increased sensitivity towards different chemotherapeutic drugs and apoptosis.
Conclusion: Our data suggest that ovarian cancer SP cells possess elevated expression of dysadherin which are responsible for ABCG2 mediated drug resistance and reduced rate of apoptosis. Therefore, novel anticancer drugs targeting the expression of dysadherin could effectively prevent the tumour recurrence and metastasis.