Melanoma, one of the most malignant tumors, is difficult to treat due to its high drug resistance. Silver nanoparticles (AgNPs) are widely used as antimicrobial agents in biomedical fields. In this study, the spherical AgNPs with average sizes of 5[Formula: see text]nm were prepared using a dopamine reduction method. The in vitro study shows that AgNPs with the concentrations of 0.5[Formula: see text][Formula: see text]g/mL and 1[Formula: see text][Formula: see text]g/mL exhibit 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 induced intracellular oxidative stress by generating the reactive oxygen species and reducing the superoxide dismutase, which further reduces the mitochondrial membrane potential. Moreover, 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 confirms 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 obtained results show the antitumor ability of AgNPs and provide a potential strategy for cancer treatment.

中文翻译：

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银纳米颗粒对 B16 黑色素瘤的体外和体内抗肿瘤活性

黑色素瘤是最恶性的肿瘤之一，由于其高耐药性而难以治疗。银纳米粒子（AgNPs）被广泛用作生物医学领域的抗菌剂。在这项研究中，使用多巴胺还原法制备了平均尺寸为 5[公式：见正文]nm 的球形 AgNP。体外研究表明，浓度为0.5[公式：见文][公式：见文]g/mL和1[公式：见文][公式：见文]g/mL的AgNPs对3T3L1成纤维细胞具有良好的生物相容性细胞。相同浓度的AgNPs显着抑制B16黑色素瘤细胞的生长。在 B16 细胞培养中，AgNPs 通过产生活性氧和减少超氧化物歧化酶来诱导细胞内氧化应激，从而进一步降低线粒体膜电位。而且，线粒体的损​​伤可以激活线粒体介导的细胞凋亡。FITC-Annexin V/碘化丙啶双染法分析B16细胞凋亡，证实AgNPs引起不同阶段凋亡细胞的丰度。因此，AgNPs 在体外显示出抗肿瘤活性。然后，在携带 B16 黑色素瘤的小鼠中评估体内治疗效果。获得的结果显示了 AgNPs 的抗肿瘤能力，并为癌症治疗提供了潜在的策略。在携带 B16 黑色素瘤的小鼠中评估了体内治疗效果。获得的结果显示了 AgNPs 的抗肿瘤能力，并为癌症治疗提供了潜在的策略。在携带 B16 黑色素瘤的小鼠中评估了体内治疗效果。获得的结果显示了 AgNPs 的抗肿瘤能力，并为癌症治疗提供了潜在的策略。