MG277 has a significantly decreased potency in reducing the level of MDM2 protein in cells and fails to activate wild-type p53. MG-277 is highly potent and effective in inhibition of cell growth in cancer cell lines with wild-type p53, mutated p53, or deleted p53, indicating a p53-independent mechanism. MG-277 induces rapid GSPT1 degradation in cancer cells in a p53- and MDM2-independent manner but in a manner dependent upon cereblon, CUL4 E3 ubiquitin ligase, and proteasomes[1].