We found that CD70-KO in C666 cells greatly enhanced cytotoxicity-dependent tumor cell death (Figs. 3j–l), preferentially in a co-culture system similar to the physiological T-cell landscape in NPC patients, with a higher expression of CD27 on CD4+ T cells (Supplementary Figs. 3h–j). This evidence concerns the gene CD4 and nasopharyngeal carcinoma.