TP53 and inflammatory bowel disease: Also supporting the contribution of programmed cell death in IBD, the apoptosis-inducing factor (PDCD8) was identified as the most regulated molecule in a proteomic analyses from intestinal tissue from IBD patients [93], along with the upregulation of PUMA (p53-upregulated modulator of apoptosis) in UC patients, which was associated with the degree of apoptosis induction and colitis severity [81].