Investigation of antiproliferative mechanisms of Alstonia angustiloba-silver nanoparticles in skin squamous cell carcinoma (A431 cell line)

Abstract

Plant-based synthesis of silver nanoparticles (AgNPs) has emerged as a promising green synthesis method. Herein, we reported the biogenic synthesis of Alstonia angustiloba-AgNPs using the aqueous extract of A. angustiloba leaves and the assessment of its antiproliferative mechanisms. Initially, the physiochemical properties of A. angustiloba-AgNPs were characterised using UV–Vis spectrophotometry, FT-IR, FESEM, EDX, TEM, and zeta sizer analyses. The cytotoxicity of A. angustiloba aqueous extract and A. angustiloba-AgNPs was examined by MTT assays against the A431 cancer cell line. The morphology of the treated cells was examined using fluorescence microscopy and the antiproliferative mechanisms of the nanoparticles in A431 cells were investigated by annexin-FITC/propidium iodide (PI) staining and DNA cell cycle analysis using flow cytometry. The results revealed that the nanoparticles showed a spherical shape with a mean hydrodynamic size of 61.21 ± 3.96 nm and a zeta potential value of –18.67 ± 3.12 mV. The nanoparticles inhibited the growth of A431 cells with an IC50 value of 39.58 µg/mL after 72 h of treatment. Further investigation has shown that the nanoparticles induced both apoptosis and cell cycle arrest in A431 cells. In summary, the present study suggests that the biosynthesised A. angustiloba-AgNPs can be further exploited for potential anticancer applications.