CASP3 and cervical carcinoma: To investigate the clinical relevance of our findings, we isolated primary cervical cancer cells from surgical samples obtained from in-house surgery and treated cells with increasing concentration of topotecan (Fig. 7A) inducing rising levels of intrinsic apoptosis, as indicated by the levels of cells in sub-G0 and caspase-3/7 activity (Fig. 7B, C).