CDK4 and gastric cancer: Moreover, the viability of neferine on gastric cancer cells was detected by the CCK8 assay, the ability of neferine to inhibit colony formation was verified by the monoclonal assay, neferine induced apoptosis in gastric cancer cells and blocked the cell cycle by flow cytometry, and neferine inhibited the proliferation of gastric cancer by inhibiting the expression of the cycling complexes CDK4/CDK6/CyclinD1, as detected by the qRT-PCR and Western Blot.