In order to further verify the contribution of mitochondria to FDN-induced apoptosis in A549 lung cancer cells, the mRNA expression levels of some Bcl-2 family members, namely Bax, Bad (pro-apoptotic protein), and Bcl-2 (anti-apoptotic), which are crucial mediators of the mitochondrial apoptotic pathway, were evaluated using qRT-PCR analysis. The gene discussed is BAX; the disease is lung cancer.