CTLA4 and neoplasm: However, the CTLA-4 and PDL-1 gene expression, which was statistically significant between triple-negative and Her-2 tumors versus Luminal A and Luminal B tumors in univariate analysis (p = 0.02 and p = 0.009), was no longer significant (p = 0.21) after adjusting for tumor grade in a multivariable regression model.