YY1 and cancer: This upregulation of p63 and p73 proteins was also observed in hMSCs undergoing apoptosis through CP2c OE or YY1 KD (Figure 4F,G) but not in cancer cells (MDA‐MB‐231 cells with a p53 R280K mutation) with normal cell proliferation by CP2c OE or YY1 KD (Figure 4D; Figure S14B, Supporting Information).