In this study, we employed the drug sensitivity data in GDSC combined with TCGA database to identify Endoplasmic Reticulum Aminopeptidase 2 (ERAP2) as the key gene associated with cellular gemcitabine sensitivity and patient prognosis, providing a new option for adjuvant gemcitabine chemotherapy for pancreatic cancer. The gene discussed is ERAP2; the disease is familial pancreatic carcinoma.