CD274 and neoplasm: To further corroborate our findings, we analyzed tumor tissues by IHC assay and found significant increased infiltration of CD8+ T cells in the stroma but decreased expression of PD-L1 and the proliferation marker Ki67 in RBMS1-depleted tumor tissues (Fig. 2I), conforming that knockdown of RBMS1 promoted anti-tumor immunity in the 4T1 tumor model.