NSC 66811 is a small-molecule inhibitor of the murine double minute 2 (MDM2) p53 interaction with Ki value of 120nM [1].
The N-terminus of p53 and a deep hydrophobic cleft in MDM2 form a short helix between p53 and MDM2. NSC 66811 binds the active site of this cleft. NSC 66811 has a high binding affinity with Ki of 120nM and is 56 times more potent than the natural p53 peptide. The stereoisomers of NSC 66811 mimic the three key residues of p53 (Phe19, Trp26, and Leu26), mediating the interaction with MDM2. NSC 66811 is reported to induce the accumulation of p53, MDM2, and p21cip1/waf proteins in the HCT-116 human colon cancer cell line with wild-type p53. However, NSC 66811 has no effect on the levels for p53, MDM2, and p21cip1/waf protein in the isogenic HCT-116 p53 /cell line [1].
References:
[1] Lu Y, Nikolovska-Coleska Z, Fang X, Gao W, Shangary S, Qiu S, Qin D, Wang S. Discovery of a nanomolar inhibitor of the human murine double minute 2 (MDM2)-p53 interaction through an integrated, virtual database screening strategy. J Med Chem. 2006 Jun 29;49(13):3759-62.