MCL1 and cancer: Given the key roles of Mcl-1 and Bcl-xl against CRC apoptosis resistance and autocrine VEGF signaling and CD133 in protecting cancer cells against drug treatment, in promoting EMT, and in supporting stem cell phenotype41, one could believe that the partially maintained pro-survival molecules (Mcl-1, Bcl-xl, VEGF, and CD133) may protect the residual cells against Rego.