JN122, a spiroindoline-containing molecule, is a MDM2 inhibitor. JN122 Inhibits MDM2/p53 protein–protein interaction and exerts robust in vivo antitumor efficacy. JN122 has antiproliferative activity in HCT-116 cells and HEK-293 cells with IC 50 values of 39.6 nM and 4.28μM, respectively. JN122 can promote activation of p53 and its target genes, inhibited cell cycle progression, and induced cell apoptosis.