CASP9 and neoplasm: The data demonstrated that TAX promoted the expression of the pro-apoptotic gene Bax, Caspase-3, and Caspase-9, and inhibited the expression of the anti-apoptotic gene Bcl-2 and oncogene Poly ADP ribose polymerase (PARP1) in SPC-A1 and LLC tumor cells (Figure 5A and Figure S3A).