Identification of novel natural treatment to combat cancer is a current need. This study was aimed at assessing the anticancer effects of ethanol-extracted Cameroonian propolis (EEP). The antitumor effect of EPP was evaluated in vitro by measuring; cell viability, cell cycle, cell death mechanism, cell migration/invasion, reactive oxygen species (ROS), mitochondrial potential (ΔΨm), caspase activity, and apoptosis-regulating proteins (Bcl-2 and Bcl-XL) in cell lines. In vivo, the effect of EEP against 7,12 dimethylbenz(a)anthracene (DMBA)-induced breast tumorigenesis in rats was assessed. EEP was found to induce cytotoxicity against ER negative MDA-MB-231 breast cancer cells by activating apoptosis through ROS-mediated mitochondrial pathway. The extract equally triggered caspase-3 and caspase-9, increment of ROS level, disruption of ΔΨm and down-regulation of Bcl-XL and Bcl-2 proteins. Besides, EPP prevented migration and invasion activities by inhibiting MMP-2 activity. At all doses it prevented breast tumor incidence (20% in EEP 150 mg/kg vs 70% in DMBA) as well as tumor burden. Tumor sections from EEP-treated rats showed middle proliferation of mammary ducts with weak inflammatory responses. In summary, Cameroonian propolis exhibited antimammary tumor effects via the intrinsic pathway of apoptosis.

中文翻译：

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Adamawa 地区（喀麦隆）蜂胶乙醇提取物的抗乳腺肿瘤作用是通过活性氧介导的线粒体途径凋亡

目前需要确定抗癌的新型自然疗法。本研究旨在评估乙醇提取的喀麦隆蜂胶 (EEP) 的抗癌作用。EPP的体外抗肿瘤作用通过测定进行评价；细胞活力、细胞周期、细胞死亡机制、细胞迁移/侵袭、活性氧 (ROS)、线粒体电位 (ΔΨm)、半胱天冬酶活性和细胞系中的凋亡调节蛋白 (Bcl-2 和 Bcl-XL)。在体内，评估了 EEP 对 7,12 二甲基苯 (a) 蒽 (DMBA) 诱导的大鼠乳腺肿瘤发生的影响。发现 EEP 通过 ROS 介导的线粒体途径激活细胞凋亡，从而诱导对 ER 阴性 MDA-MB-231 乳腺癌细胞的细胞毒性。提取物同样触发 caspase-3 和 caspase-9，增加 ROS 水平，ΔΨm 的破坏和 Bcl-XL 和 Bcl-2 蛋白的下调。此外，EPP 通过抑制 MMP-2 活性来阻止迁移和侵袭活动。在所有剂量下，它都能预防乳腺肿瘤发生率（EEP 150 mg/kg 为 20%，DMBA 为 70%）以及肿瘤负荷。来自 EEP 治疗的大鼠的肿瘤切片显示出具有微弱炎症反应的乳腺导管的中等增殖。总之，喀麦隆蜂胶通过细胞凋亡的内在途径表现出抗乳腺肿瘤作用。