CTLA4 and neoplasm: The values were not correlated with the stage of the tumor.3 These peritumoral CD4+CD25+ T cells had a regulatory phenotype, as indicated by an increased expression of several molecules (e.g., cytotoxic T lymphocyte antigen 4 [CTLA-4, CD152] and glucocorticoid-induced TNF receptor superfamily member 18 [GITR, CD357]), expression of a biomarker for regulatory T cells (i.e., FOXP3), and decreased expression of CD45RA.