Promotion of apoptosis in leukemia K562 cells by natural plant-derived antimicrobial solution(PAMs)

In this study, the leukemia K562 cell line was used as a model to elucidate the anticancer effects and preliminary mechanisms of PAMs. MTT assay showed that PAMs could cause cytotoxicities in K562 cells in dose- and time-dependent manners. AO-EB, Annexin-FITC/PI staining showed that the killing effects of PAMs in K562 cells were related to apoptosis, which was further confirmed by the following molecular and enzymatic assay. The mRNA levels of pro-apoptotic genes caspase-3, caspase-9 and bax were remarkably increased while the anti-apoptotic gene bcl-2 was significantly decreased determined by fluorescent quantitative PCR. Western blotting disclosed that PAMs could up-regulate caspase-3 and down-regulate anti-apoptotic survivin protein expression. The latter was also consistent with the results that PAMs could increase the enzymatic activities of both caspase-3 and caspase-9. All these results suggested that PAMs could effectively inhibit the proliferation of K562 cells and the mechanisms may be closely related to apoptosis induction. The work provides evidence basis for PAMs to be potentially developed as anti-cancer leukemia Chinese medicine.