Over-expression of Cyclin D1 was found to confer gemcitabine and cisplatin resistance to pancreatic cancer cell [49]; CCNE1, CDK2, and CDKN1A, previously reported to be up-regulated by gemcitabine as confirmed in our study, were also implied in chemotherapy resistance [50,51]. The gene discussed is CDKN1A; the disease is pancreatic neoplasm.