Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
Medical Oncology Unit - IRCCS Istituto Tumori "Giovanni Paolo II" of Bari, Italy; Department of Biomedical Sciences and Human Oncology, University of Bari "Aldo Moro", Bari, Italy.
Int J Biol Macromol. 2020 Nov 1;162:1283-1292. doi: 10.1016/j.ijbiomac.2020.06.130. Epub 2020 Jun 18.
Breast cancer (BC) is among the leading causes of mortality from cancer in women. Many of the available anticancer drugs have various side effects. Therefore, researchers are seeking novel anticancer agents particularly from natural compounds and in this regard, snake venom is still one of the main sources of drug discovery. Previous studies showed potential anticancer effects of Cytotoxin II (CTII) from Naja naja oxiana against the different types of cancers. In this study, a pET-SUMO-CTII vector was transformed into SHuffle® T7 Express, an Escherichia coli strain, for recombinant protein expression (rCTII) and the cytotoxic effects of this protein was assessed in MCF-7 cells. The flow cytometry assay was applied to measure the apoptosis and cell cycle. Also, mRNA levels of the Bax, Bcl2, P53, caspase-3, caspase-8, caspase-9, caspase-10, matrix metalloproteinases (MMP)-3, and MMP-9 were analyzed by quantitative real-time PCR to determine the underlying cellular pathways affected by rCTII. The results of this study showed that treatment with 4 μg mL of rCTII enhanced apoptosis through the intrinsic and extrinsic pathways. Also, the increase of the cells' proportion in the sub-G1 phase as well as a reduction in S phase was observed. In addition, the expression of MMP-3 and MMP-9 was decreased in the treated group in comparison to the control group that may contribute to the reduced migratory ability of tumor cells. These experimental results indicate that rCTII has anti-proliferative potential, and so this protein could be a potential drug for BC therapy in combination with other drugs.
乳腺癌（BC）是女性癌症死亡的主要原因之一。许多现有的抗癌药物都有各种副作用。因此，研究人员正在寻找新的抗癌药物，特别是从天然化合物中寻找，在这方面，蛇毒仍然是药物发现的主要来源之一。以前的研究表明，来自眼镜蛇的细胞毒素 II（CTII）对不同类型的癌症具有潜在的抗癌作用。在这项研究中，将 pET-SUMO-CTII 载体转化为 SHuffle® T7 Express，一种大肠杆菌菌株，用于重组蛋白表达（rCTII），并评估该蛋白在 MCF-7 细胞中的细胞毒性作用。流式细胞术用于测量细胞凋亡和细胞周期。此外，通过定量实时 PCR 分析 Bax、Bcl2、P53、caspase-3、caspase-8、caspase-9、caspase-10、基质金属蛋白酶（MMP）-3 和 MMP-9 的 mRNA 水平，以确定受 rCTII 影响的潜在细胞途径。这项研究的结果表明，用 4μg/mL 的 rCTII 处理可通过内在和外在途径增强细胞凋亡。此外，观察到细胞在 S 期的比例增加和亚 G1 期的比例减少。此外，与对照组相比，处理组中 MMP-3 和 MMP-9 的表达降低，这可能有助于降低肿瘤细胞的迁移能力。这些实验结果表明，rCTII 具有抗增殖潜力，因此该蛋白可能与其他药物联合用于治疗 BC。
