Green Synthesized Silver Nanoparticles Induce Apoptosis and G2/M Arrest Via Signalling Pathways in MCF-7 Breast Cancer Cell Lines.

Abstract

Objective: In the present study, silver nanoparticles (AgNPs) were synthesized from leaf extracts of Cleome gynandra, and their anticancer and antioxidant activities were evaluated.

Experimental: The synthesized silver nanoparticles were characterized by UV-visible spectroscopy (UV-Vis), Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Photoluminescence analysis, Zeta Potential, and Particle size analysis. The SEM image showed rod-shaped silver nanoparticles with a diameter range of 520nm. The maximum absorption of silver nanoparticles was recorded at 400nm in UV-visible spectroscopy due to Surface Plasmonic Resonance (SPR). FT-IR spectroscopy revealed that silver nanoparticles had different functional groups. Synthesized AgNP was assessed for its antioxidant and cytotoxic effect against MCF-7 cells.

Results: The zeta potential for silver nanoparticles was found to be -18.2 mV which indicated their stability. The photoluminescence results confirmed an excitation peak at 397.07nm and an emission peak at 579.85nm. The synthesized silver nanoparticles were subjected to anticancer and antioxidant activities. Antioxidant results determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay,  hydrogen peroxide assay, and reducing power assay revealed efficient antioxidant potential of the biosynthesized AgNPs. MCF cells treated with the nanoparticle showed a significant decrease in cell viability in a concentration-dependent manner.

Discussion:  DNA fragmentation assay showed that the AgNPs induced apoptosis by cleaving nuclear DNA by forming a ladder pattern. Apoptotic activity of the nanoparticles could be due to the accumulation of the AgNPs in the mitochondria and nucleus. They interact with DNA and damage the cells.

Conclusion: Based on the results obtained, it is evident that the aqueous extract of Cleome gynandra is an effective reducing agent for the green synthesized AgNPs with antioxidant and anticancer activities, which provides a promising approach for alternative nano-drug development.