ABCG2 and familial pancreatic carcinoma: We also investigated the expression levels of the pancreatic cancer stem cell markers ABCG2 [12] and EZH2 [13] by qRT-PCR, and we found that ABCG2 and EZH2 mRNA expression levels were significantly decreased following siRNA-mediated knockdown of PIM-1 expression (Fig. 3).