The present work was designed to study the effect of new conjugated caffeic and folic acid with silver nanoparticles with definite molecular size applied with and without gamma radiation exposure, as an antitumor agent against experimentally induced Ehrlich tumor and attempted to identify their potential molecular mechanisms of action throughout determination of anti-tumor activities using MTT cytotoxic assay against two human carcinoma cell lines in vitro, such as apoptosis analysis by flow cytometry through caspase-8, caspase-3 and TNF determination in vivo. This evidence concerns the gene CASP8 and Ehrlich tumor carcinoma.