HLA-C and neoplasm: In contrast, PHLDA2 was negatively correlated with the infiltration levels of several immunocompetent tumor-infiltrating cells, including TemCD8, Th1, and NKT cells, and PHLDA2 was negatively correlated with most immunomodulators (immune promoters, MHC molecules, chemokines, and chemokine receptors) in PAAD, so they can be used as potential targets of PAAD immunotherapy and molecular indicators to predict the efficacy of immunotherapy.