Fig 9.

SCO2-induced expression of apoptotic genes is absent in ASK-1 knockdown tumors. A PCR gene array for genes involved in the regulation of cellular apoptosis was conducted by using SCO2 cDNA-transfected HCT p53^+/+, HCT p53^−/−, HCT p53^+/+ ASK-1^−/−, and HCT p53^−/− ASK-1^−/− tumor xenografts. SCO2 transfection in the HCT p53^+/+ and HCT p53^−/− tumors resulted in significant increases in apoptotic gene expression levels (lanes 1 and 2). The effect of SCO2 on the expression of apoptotic genes was abolished in HCT p53^+/+ ASK-1^−/− and HCT p53^−/− ASK-1^−/− tumor xenografts (lanes 4 and 6). NAC- and SCO2-treated tumors (lanes 8 and 10 to 12) and untreated tumors (lanes 3, 5, 7, and 9) were used as controls (n = 5).