A.G. Reznikov, O.A. Salivonyk, O.V. Sachynskaya, L.V. Chaikovskaya, L.I. Polyakova, V.N. Grigorenko, A.V. Usatenko

Study of the gold nanoparticles various dosage effects on human prostate cancer xenografts

Administration of the gold nano-particles might be one of the promising therapeutic modalities in prostate cancer. In this work, there were studied effects of colloidal solution of the gold nano-particles covered with polyvinylpyrrolidone with an average size of 25 nm at daily doses of 0.64 mg/kg, 1.7 mg/kg, 6.4 mg/kg body weight subcutaneously on growth and histological structure of the human prostate cancer xenografts that had been transplanted under the kidney capsule of CBA mice.Injections of the preparation have been started on the fourth day after transplantation. Effect of the treatment on the xenografts growth and histology of the xenografts and gonads in comparison with controls was evaluated. Androgen-dependent phenotype of the tumors was proved by xenografts growth attenuation after androgen ablation in previously castrated recipient mice. Three-day administration of the preparation caused growth arrest of the xenografts. Pathohistological examination of the xenografts revealed the features of dose-dependent cytotoxic effect of gold nanoparticles on malignant prostate epithelium. The gonad weights did not change, pathomorphological changes in their tissues were not revealed. This observation indicates that gold nano-particles effect on the tumor tissues is rather the result of direct influence, not a decrease in testosterone secretion. The results of the study make reasonable further investigation gold nano-particles effects on prostate cancer in other experimental models.