Fig. 4. Cytotoxic effects of topotecan treatment in SW620 and SKOV3 cell lines (Annexin V/PI and Western blot assays).

The cells were treated with topotecan (20 nM for SW620, 70 nM for SKOV3) in the presence or absence of 25 μM of Q-VD. a Fractions of viable and apoptotic cells estimated with the Annexin V/PI assay. The lines and whiskers indicate mean ± standard deviation (N = 5). b Western blot analysis of protein levels. The samples are indicated above; the proteins of interest are indicated on the left; molecular weight markers are indicated on the right. “Contr” – control samples; “Topo” – topotecan.