Higher NO levels may exert cytotoxic effects and induce apoptosis or programmed cell death in cancer cells and affect the apoptosis process by regulating Bcl-2 family proteins, promoting the expression of pro-apoptotic proteins such as Bax and Bad, and inhibiting the expression of anti-apoptotic proteins Bcl-2 and Bcl-xL (82). This evidence concerns the gene BCL2 and cancer.