Runt-related transcription factor 3 is a protein in humans that is encoded by RUNX3 gene. CBF binds to the core site, 5'-PYGPYGGT-3', of a number of enhancers and promoters, including murine leukemia virus, polyomavirus enhancer, T-cell receptor enhancers, lck, IL-3 and GM-CSF promoters. In association with ZFHX3, upregulates CDKN1A promoter activity following TGF-beta stimulation.