CD4 and neoplasm: Tumor-proximal DCs can capture the antigens generated and released during tumorigenesis and present captured tumor-associated antigens (TAAs) in cooperation with costimulatory molecules, such as CD80 and CD86, through the major histocompatibility complex (MHC)-I and MHC-II molecules to naïve CD8+ T cytotoxic cells and naïve CD4+ T helper cells, respectively, leading to the initiation and activation of antitumor immune responses (76, 77).