Malignant melanoma is an aggressive cancer with a poor prognosis despite numerous advances in therapeutic strategies. Quercetin is a plant-derived flavonoid suggested to have potent anticancer properties. Quercetin has no demonstrable toxicity in humans, further supporting the possibility of using quercetin therapeutically. We chose to investigate quercetin efficacy against B16 murine melanoma cells and identify the mechanisms of anticancer activity. Treatment of B16 melanoma cells with 50 μg/mL quercetin resulted in a 75% reduction in viability from 6 through 48 h post-treatment. The reduction in cancer cell viability was comparable to or greater than what was observed with etoposide, an established chemotherapeutic. Specifically, we found Quercetin reduced the proliferation of B16 melanoma cells at 48 h as much or more than etoposide. Although quercetin reduced the proportion of cells in the S and G2/M stages of the cell cycle, this could largely be explained by an increase in the subG1 population in quercetin-treated cells (suggesting apoptosis). Quercetin-induced apoptosis was confirmed by flow cytometry analysis of Annexin V+ cells. Collectively, our findings demonstrate quercetin reduces proliferation and induces apoptosis of B16 melanoma cells in vitro.

中文翻译：

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槲皮素在体外抑制 B16 黑色素瘤细胞的增殖并诱导其凋亡。

尽管治疗策略取得了许多进展，但恶性黑色素瘤是一种预后不良的侵袭性癌症。槲皮素是一种植物来源的黄酮类化合物，被认为具有有效的抗癌特性。槲皮素对人体没有明显的毒性，进一步支持了槲皮素用于治疗的可能性。我们选择研究槲皮素对 B16 鼠黑色素瘤细胞的功效并确定抗癌活性的机制。用 50 μg/mL 槲皮素处理 B16 黑色素瘤细胞导致处理后 6 至 48 小时的存活率降低 75%。癌细胞活力的降低与依托泊苷（一种已建立的化学治疗剂）所观察到的相当或更大。具体来说，我们发现槲皮素在 48 小时内减少 B16 黑色素瘤细胞的增殖与依托泊苷一样多或更多。尽管槲皮素降低了细胞周期 S 和 G2/M 阶段的细胞比例，但这在很大程度上可以通过槲皮素处理的细胞中亚 G1 种群的增加来解释（表明细胞凋亡）。通过膜联蛋白 V+ 细胞的流式细胞术分析证实了槲皮素诱导的细胞凋亡。总的来说，我们的研究结果表明槲皮素可减少 B16 黑色素瘤细胞的增殖并诱导其凋亡体外。