The heterogeneity and poor prognosis of triple-negative breast cancer (TNBC) have limited the treatment options and made clinical management challenging. This has nurtured a major effort to discover druggable molecular targets. Currently, chemotherapy is the primary treatment strategy for this disease. Doxorubicin is the most frequently used chemotherapeutic drug for TNBC and due to the fact that chemotherapeutic drugs have a lot of side effects, we evaluated the synergistic effect of the phytocompound anethole and doxorubicin. The cytotoxic effect of anethole in combination with doxorubicin on MDA-MB-231 cells was evaluated by various parameters, including apoptosis, cell cycle analysis, DNA damage, and cell proliferation. Furthermore, mitochondrial membranepotential (MMP), endoplasmic reticulum (ER) stress, and reactive oxygen species (ROS) levels were also evaluated in the cells treated with/without anethole and doxorubicin. Expression of the apoptotic proteins was evaluated by Western blot analysis. Initial evaluation of cytotoxicity of anethole on MDA-MB-231 cells demonstrated preferential suppression of cell proliferation and when treated along with doxorubicin it showed enhanced cytotoxicity with a synergistic effect. Cell cycle analysis revealed arrest at different stages of the cell cycle, such as sub G0-G1, G0-G1, S, and G2M in various treatment groups and apoptotic cell death was subsequently evident with propidium iodide (PI) staining. The synergistic action of anethole and doxorubicin effectively induced mitochondrial membrane potential loss, which, in turn, led to a burst of ROS production, which eventually produced unfolded protein response by damaging the ER. Synergistic anticancer effect was observed on exposure of MDA-MB-231 cells to anethole and doxorubicin in inducing cell death.

中文翻译：

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茴香脑和多柔比星的协同作用可减轻三阴性乳腺癌细胞的细胞增殖、细胞周期停滞和内质网应激，并促进 ROS 介导的细胞凋亡

三阴性乳腺癌 (TNBC) 的异质性和预后不良限制了治疗选择，并使临床管理具有挑战性。这促进了发现可药用分子靶点的重大努力。目前，化疗是该病的主要治疗策略。阿霉素是 TNBC 最常用的化疗药物，由于化疗药物有很多副作用，我们评估了植物化合物茴香脑和阿霉素的协同作用。茴香脑联合阿霉素对 MDA-MB-231 细胞的细胞毒作用通过各种参数评估，包括细胞凋亡、细胞周期分析、DNA 损伤和细胞增殖。此外，线粒体膜电位 (MMP)、内质网 (ER) 应激、还评估了用/不用茴香脑和阿霉素处理的细胞中的活性氧 (ROS) 水平。通过蛋白质印迹分析评估凋亡蛋白的表达。茴香脑对 MDA-MB-231 细胞的细胞毒性的初步评估显示优先抑制细胞增殖，并且当与多柔比星一起处理时，它显示出增强的细胞毒性和协同效应。细胞周期分析显示细胞周期的不同阶段停滞，例如不同治疗组的亚 G0-G1、G0-G1、S 和 G2M，随后用碘化丙啶 (PI) 染色明显可见凋亡细胞死亡。茴香脑和多柔比星的协同作用有效地诱导了线粒体膜电位的丧失，这反过来又导致了 ROS 的产生，最终通过破坏 ER 产生未折叠的蛋白质反应。在 MDA-MB-231 细胞暴露于茴香脑和多柔比星诱导细胞死亡时观察到协同抗癌作用。