As expected, Nano-MP@PSI is highly active against retinoblastoma in vitro and in vivo through MDMX degradation and subsequent p53 as well as p73 restoration, and it suppressed the tumor progression in a patient-derived tumor xenograft (PDX) model of pancreatic carcinoma harboring the mutant Kras G12D, while showing a highly favorable clearable profile of rapid excretion from the living body. This evidence concerns the gene MDM4 and neoplasm.