In the context of tumorigenesis and tumor development, B cells often inhibit anti‐tumor immune responses through IC signaling, thereby promoting tumor progression.[26] These IC signals regulate CD4+ T cells, CD8+ T cells, and regulatory T cells (Tregs), promote the release of IL‐10 from B cells and influence the functions of antigen presentation, co‐stimulation and memory properties of B cells, thus directly or indirectly modulating tumor immunity (Figure 2). Here, CD4 is linked to neoplasm.