CD4 and neoplasm: Among the 22 subtypes of tumor-infiltrating immune cells in TIMER version 2.0 database, higher infiltrating percentage of macrophages M0, macrophages M2 and neutrophils were significantly associated with the poor prognosis of BCa, while lower infiltrating percentage of T cells CD8, T cells CD4 memory activated or T cells follicular helper were significantly associated with the poor prognosis of BCa according to the risk score derived from the molecular prognostic index (P < 0.05, Fig. 10a).