Several studies have demonstrated that SNPs in some genes, such as EGFR and p53, and in microRNAs are related to lung cancer development.8, 9, 10, 11 Our recent study showed that USP24 variants from SNPs and RNA editing products increased the levels of USP24 and MDM2, which regulates Suv39h1 in lung cancer cells, subsequently resulting in an increase in metastatic activities during lung cancer progression.12 However, the role of USP24 in cancer formation is unknown. Here, MDM2 is linked to lung cancer.