AB055. PKCε inhibits isolation and stemness of side population cells via the suppression of ABCB1 transporter and PI3K/Akt, MAPK/ERK signaling in renal cell carcinoma cell line 769P

BACKGROUND: In this study, to identify the function of PKCε in renal cancer stemness of 769P SP cells. METHODS: we reduced the expression of PKCε in 769P cells by using siRNA. Then, the ratios of sorted SP cells were evaluated. Moreover, cancer stem cell (CSC) phenotype of 769P SP cells was assessed by performing clone formation assays, drug sensitivity assays in vitro and in vivo. RESULTS: Down-regulation of PKCε suppressed the CSC potential of sorted 769P SP cells and inhibited proliferation potential, resistance to chemotherapeutics and in vivo tumor formation ability. CONCLUSIONS: Our study reveals that PKCε contributed to the SP cells isolation from 769P cell line, proliferation, and resistance to chemotherapeutics. Thus, PKCε may work as an important mediator in cancer stem cell pathogenesis of renal cell cancer.