Crude or semi-purified extracts of plants can play a significant role as antitumor agents. They were used as stabilizing and reducing agents in the preparation of silver nanoparticles (AgNPs) that allows these particles to have more efficient cytotoxic activity. In the current study, the extract of Marrubium alysson L., a plant of common occurrence in Egypt was used to synthesize AgNPs for the first time, where comparison of anticancer activity of crude and phenolic extracts with the AgNPs were extensively studied against cancer cell lines PC-3 and HCT-116. Interestingly, AgNPs of the crude extract exhibited promising cytotoxicity with IC50 values of 10.4 and 16.3 μg/ml, while AgNPs of the phenolic extract exhibited very potent cytotoxicity with IC50 values of 2.66 and 1.34 μg/ml compared to Doxorubicin (as a standard reference drug) that exhibited IC50 values of 5.13 and 4.36 μg/ml, respectively against the tested cells. Additionally, AgNPs of the phenolic extract induced apoptosis in HCT-116 with a higher ratio than in PC-3 cells. It induced apoptosis in PC-3 cells by 79.3-fold change, while it induced total colon apoptotic cell death by 228.3-fold change compared to untreated control. Finally, the apoptotic activity of AgNPs of the phenolic extract in the treated PC-3 and HCT-116 cells was confirmed using RT-PCR. As a result, AgNPs of the phenolic extract could be considered a promising anticancer candidate through apoptosis-induction.Communicated by Ramaswamy H. Sarma.
Keywords: Marrubium alysson L; PC-3 and HCT-116; apoptosis; silver nanoparticles.