IL10 and neoplasm: Anti-tumorigenic B cells have a strong tumor suppressive activity by presenting tumor antigens to T cells and producing anti-tumor antibodies (IgG1), but specific pro-tumorigenic B lymphocyte subsets, namely, regulatory B (Breg) cells secrete immunosuppressive cytokines such as IL-10 and IL-35 thereby promoting cancer progression and evading immunosurveillance in PDAC (20).