Preparation, Characterization and in Vitro Evaluation of the Antitumor Activity of the Biologically Synthesized Silver Nanoparticles

Abstract

This study was concentrated on the biosynthesis of silver nanoparticles from Penicillium auran-tiogresium (IMI 89372) with a focus on its cytotoxicity in MCF-7 and MCT cancer cell lines as well as Vero (normal) cell line that was assessed by crystal violet assay after treatment with various concentrations (0.44 – 145 µg/ml) for 24 h. The cell morphology was examined by inverted light microscopy. Further, the radiosensitizing effect of silver nanoparticles (AgNPs) on MCF-7 was also demonstrated by assessing cell morphology, cell proliferation of MTT assay, LDH activity and in-duction of apoptosis through checking of some apoptotic genes that altered during carcinogenesis, including caspase-3, Bax and Bcl-2. Caspase-3 activity was also estimated. Synthesis of AgNPs was determined by UV-Visible spectrum and it was further characterized by TEM, FT-IR and X-Ray analysis (EDX, XRD). The biosynthesized AgNPs were spherical and of 12.7 nm in size as recorded by direct electron microscopy visualization. The biosynthesized AgNPs showed variation in cyto-toxicity against MCF-7, MCT and Vero cell lines in a concentration dependant response with a var-ied degree of alteration in cell morphology. The result showed that AgNPs were highly toxic to-wards MCF-7 with IC50 value of 10.5 µg/ml. Treatment of MCF-7 (10.5 µg/ml) prior to irradiation improved the effect of irradiation dose (6 Gy) via increasing alteration of cell morphology, inhibi-tion of cell proliferation, activation of the lactate dehydrogenase (LDH) and caspase-3 leading to induction of apoptosis which was further confirmed through increasing nuclear DNA damage and up regulation of caspase 3 and Bax genes and downrgulation of Bcl-2 genes. In conclusion, the present findings clearly indicated that AgNPs showed dose dependant cytotoxicity and verified * Corresponding author. O. E. Elshawy et al. 150 that AgNPs acted as a potent radiosensitizer and could enhance gamma irradiation induced killing of MCF-7 breast cancer cells.