RRM2 and neoplasm: Inhibition of pancreatic cancer cell lines by co-administration of Adriamycin and RRM2 siRNA was four times higher than that provided by Adriamycin administration alone (41).RRM2 overexpression upregulates VEGF in oral and pancreatic cancers and promotes tumor angiogenesis through the PI3K/AKT signaling pathway (42, 43).