Zheng et al. further showed the Berberine-induced lung cancer cell proliferation inhibition and G2/M cell cycle arrest is mediated by reducing the expressions of transcription factor SP1 and 3-phosphoinositide-dependent protein kinase-1 (PDPK1), which was suggested to prevent the interaction between the two, resulting in the inhibition of a downstream effector DNA methyltransferase 1 (DNMT1) expression involved in tumor growth and progression [101]. This evidence concerns the gene DNMT1 and lung cancer.