RUNX3 and immune system disorder: RUNX is a family of proteins that participate down-stream of TGF-β1 signaling, and their loss is involved in severe inflammation and tumor formation in the gastrointestinal tract [95]; RUNX3 is involved in the differentiation of CD8 and NK cells; thus, Runx3−/− mice develop immunodeficiency by the absence of these cells [96].