Regarding caspase activities (Figure 2B), we observed that CIS did not induce caspase-9 activation in SiHaCIS-R; while PTX alone or in combination with CIS induced higher activity of caspase-9 in SiHaP and SiHaCIS-R cells compared to the UCG or CIS treatment (p < 0.001). This evidence concerns the gene CASP9 and in situ carcinoma.