In pancreatic cancer, one study showed that a distinct population of CD133pos/CXCR4pos expressing CSCs were exclusively tumorigenic, mediated metastasis, and highly resistant to chemotherapy [117], however, a more recent study countered this notion by suggesting that CD133 is not a robust marker for CSCs in pancreatic cancer [118]. The gene discussed is PROM1; the disease is pancreatic neoplasm.