CD8A and familial pancreatic carcinoma: Moreover, the protein expression level of ITGA2 in pancreatic cancer tissues was negatively correlated with the protein expression levels of CD4 and CD8 (r = -0.344, P < 0.05 and r = -0.398, P < 0.05, respectively).The study found that as the expression level of ITGA2 increased, the expression level of CD4 and CD8 protein decreased.