Our results showed gene up-regulation of CASP 9, CASP 7, and CASP 3 as well as protein up-regulation of active-caspase 3 and cleavage-PARP with TB treatment (Figures 6 and 7), indicating intrinsic caspases pathway as a main pathway involved in TB-induced apoptosis of A549 cells. The gene discussed is CASP3; the disease is tuberculosis.