MDM2 and neoplasm: Similarly, HDM201, an MDM2 inhibitor, inhibited the ubiquitinated degradation of p53 by MDM2, increased dendritic cells as well as the CD8+/Treg ratio, promoted a durable tumor-specific immune memory response and improved the anti-tumor response of anti-PD-L1 antibody/anti-PD-1 antibody against colon cancer.160