CTLA4 and neoplasm: Individual markers such as CD274 (PD-L1) (P = 0.04) and CTLA4 (P = 0.01) as well as signatures associated with effector cell types such as activated CD8 T cells (P = 0.05) and NK cells (P = 0.05) were also significantly elevated in responders based upon pretreatment tumor samples.