Wild-typep53 (tumor suppressor transcription factor TP53) and mutated RAS-bearinglung adenocarcinoma cell line A549 was used as a model in our studies.Here, we demonstrate cisplatin concentration-dependent opposing rolesof JNK in killing cancer cells: a cell-protective role at low cisplatinconcentrations and an apoptosis-promoting (or neutral) role at highconcentrations. The gene discussed is TP53; the disease is cancer.