Based on the finding that melatonin significantly inhibited cell proliferation through inhibiting PRMT1 expression in p53-wild NSCLC cells (Fig. 1, Fig. S6A, C) but had no effect on PRMT1 protein in p53-deficient and p53-mutated NSCLC (Fig. 4), we hypothesized that inhibition of PRMT1 could further enhance the anticancer effects of melatonin. This evidence concerns the gene TP53 and non-small cell lung carcinoma.