Recently, we found that p53 in renal cell carcinoma (RCC) cells can be regulated by both mouse double minute 2 homolog (protein: MDM2; gene: MDM2) through proteasomal degradation [1] and by transglutaminase 2 (protein: TGase 2; gene: TGM2) through autophagosomal degradation [2]. The gene discussed is MDM2; the disease is renal cell carcinoma.