CD4 and cancer: According to the findings, PRKDC was relevant to tumor purity in 9 different kinds of cancers, and also remarkably associated with the infiltration levels of B cells, CD8+ T cells, CD4+ T cells, macrophages, neutrophils, and DCs in 15, 21, 14, 18, 21, and 19 kinds of tumors, separately (Fig. 5A and Fig S4–7, Supplemental Digital Content, http://links.lww.com/MD/G879).