In this study, we demonstrated the inhibitory effect of PPI on lung cancer cell growth through stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK)-mediated inhibition of NF-kB subunit p65 and DNMT1 protein levels, subsequently; this resulted in the reduction of EZH2 gene expression. The gene discussed is MAPK9; the disease is lung carcinoma.