STAT3 and neoplasm: The findings from these studies of human Bregs in cancer underscores the ability of different Breg subsets to mediate immunosuppression in support of tumour growth through a variety of mechanisms; suppressive cytokine production (IL-10, TGF-β, IL-35), suppression of T cells and NK cells and the expansion of suppressive Tregs and myeloid-derived suppressor cells [30], expression of inhibitory ligands such as PD-L1 to dampen anti-tumour immunity [81] and STAT3 mediated promotion of angiogenesis and Treg augmentation [22, 68, 82].