Signaling gene cascade in silver nanoparticle induced apoptosis.

Nanoscale materials are presently gaining much importance for biological applications especially in the field of medicine. The large numbers of nanomaterial based products that are currently being developed - with projected applications in medicine - have inspired a growing interest in exploring their impact on cellular gene expression. The present study examines the effects of silver nanoparticles (NPs) on genes expression in an endeavor to assess the fundamental mechanisms that contribute to silver NP induced programmed cell death. Here, we have used RT-PCR to study the gene expression, flow cytometry analyses to probe the extent of apoptosis (FACS) and atomic force microscopy (AFM) to follow the cell membrane topology change induced by Ag NPs. The gene expression study revealed that Ag NP induced p53-mediated apoptotic pathway through which most of the chemotherapeutic drugs trigger apoptosis (programmed cell death). The results also suggest that Ag NPs could be attributed as therapeutic agent for biomedical and pharmaceutical applications. Copyright 2010 Elsevier B.V. All rights reserved.