Cancer stem cell markers, Nanog, Oct-4 and SOX-2, are upregulated in cisplatin resistant cells.

<p> Total proteins were isolated from parent and corresponding cisplatin resistant sublines and subjected to SDS-PAGE gel electrophoresis and transfer by Western blot. Using a panel of human embryonic stem cell markers, Nanog, Oct-4 and SOX-2 protein expression was examined between parent and resistant cell lines. While H460, A549 and SKMES-1 resistant cells exhibited increased expression of Nanog and SOX-2 proteins, Oct-4 expression was significantly upregulated in MOR, H460 and A549 cells only. Cisplatin resistant MOR cells demonstrated increased levels of SOX-2 and Oct-4 proteins relative to parental cells. Data are expressed as Mean ± SEM from three independent experiments (n = 3) (^*p<0.001).