Role of reactive oxygen species: In the cytotoxicity and apoptosis of colon cancer cell line due to green lead nanoparticles

Nanoparticles are involved in regulating the biology of cancer cell treatment, but their mechanism is not fully understood. We synthesized and characterized new green lead nanoparticles (gPbNPs) by using an extract of Ziziphus spina christi leaves. Its cytotoxic and apoptotic effect on the human colon cancer Cacoa2 cell line was evaluated. The gPbNPs were characterized by using energy dispersive X-rays, scanning electron microscopes, and transmission electron microscopes. The cytotoxic effects of gPbNPs against the human colon cancer Cacoa2 cell line were investigated, as were the possible mechanisms underlying the induction of apoptosis. In this experiment, we observed the production of intracellular reactive oxygen species (ROS) in cells, and the installation of caspase 3/7 was higher in cells at 16 mu g/mL of gPbNPs. Moreover, the Bax gene was upregulated and the Bcl2 gene was downregulated, and increased caspase-3/7 activity confirmed the apoptotic effect of gPbNPs in cells. The cytotoxicity test confirmed that gPbNPs were selectively toxic in cancer cells and induced apoptosis by activating bad, bax, caspase-3/7, p27, p53 protein, and proteins involved in apoptosis. Our observation showed that gPbNPs induced cell toxicity, increased generation of intracellular ROS, and gene expression of Bcl2, and Bax, in the Cacoa2 cell line. In conclusion, these findings demonstrated that gPbNPs executed toxic effects on the Cacoa2 cell line by activating caspase-3/7 activity.