Figure 4.

Pro-apoptotic activity of alkaloids 1–8 in human cancer cells. (A) Analysis of DNA fragmentation in HeLa cells treated with compounds 1–8 for 48 h at the concentrations of IC₅₀. The number of cells with fragmented DNA was assessed with flow cytometry and assumed as the sub-G1 population in cycle analysis; and (B) analysis of caspase-3/7 activity in HeLa cells under the treatment with the compounds 1–8 at the concentrations of IC₅₀ for 48 h. Cisplatin was used as a positive control. Concentrations used corresponded to IC₅₀ for HeLa cells as presented in Table 1. * indicates a statistically significant difference (p < 0.05) from the control value.