In Vitro And In Vivo Antitumor Activity Of Silver Nanoparticles On B16 Melanoma

Melanoma is one of the most malignant tumors.Melanoma has a high mortality rate due to its high drug resistance and advanced metastatic properties.The current therapeutic agents used for melanoma treatment are inefficient due to severe side effects and toxicity on noncancerous tissues.It is well known that silver nanoparticles(AgNPs)are widely used as antimicrobial agents in biomedical fields.With further research on AgNPs,it has been found that AgNPs have powerful cytotoxicity to tumor cells.Although AgNPs are gradually promoted and used in cancer treatment,they have side effects on normal tissues.Therefore,how to increase the biological safety of AgNPs without affecting its excellent anti-tumor activity is a challenge that people face.In this study,the spherical AgNPs with average sizes of 5 nm and good dispersion were prepared using a dopamine reduction method.In vitro study,through cell proliferation,live/dead staining and cell nuclear staining,AgNPs with the concentrations of 0.5 ?g/m L and 1?g/m L showed the good biocompatibility to 3T3L1 fibroblast cells.AgNPs with the same concentrations significantly inhibited the growth of B16 melanoma cells.In culture with B16 cells,AgNPs increased the content of reactive oxygen species(ROS)and reduce the activity of superoxide dismutase(SOD),indicating AgNPs induced intracellular oxidative stress by the generation of ROS and the reduction of SOD.Excessive oxidative stress causes a decrease in mitochondrial membrane potential,which leads to the damage of mitochondrial.JC-1staining confirmed the damage of mitochondrial membrane.The damage in mitochondria could activate mitochondrion-mediated cell apoptosis.The B16 cells apoptosis was analyzed by FITC-Annexin V/propidium iodide double staining assay,which confirmed that AgNPs caused the abundance of apoptotic cells in different stages.Thus,AgNPs displayed the antitumor activity in vitro.Then,the therapeutic efficacy in vivo was evaluated in mice bearing B16 melanoma tumors.The results revealed that tumor-bearing mice in the treated group had the smallest tumor volume and the highest survival rate.The results of tissue staining showed that AgNPs caused a weak inflammatory response to the kidneys of mice,but the heart,liver,spleen,and lung tissue were normal.In conclusion,AgNPs exhibited antitumor ability in vivo and in vitro in this work.The present study also provided a potential strategy for cancer treatment.