Other studies have reported models focusing on one [30] or on parallel [31] pathways of inhibitory factors induced by Treg, TGF-β and/or IL-10 that promote tumor growth and reduce the cytotoxicity of effector cells (i.e., CD8+ cells and others such as DC, CD4+ helper T cells, and IL-2). This evidence concerns the gene TGFB1 and neoplasm.