As shown in Fig. 7A, the expression of p-AKT, TYMS, DHFR, CDK4, CDK6, Cyclin D1, Cyclin E2, and p-RB was significantly downregulated both in A549 and H1299 cells treated with diosbulbin C as compared to the untreated groups, further proving the effect of diosbulbin C on cell cycle progression in NSCLC. This evidence concerns the gene DHFR and non-small cell lung carcinoma.