Life Sciences Institute, Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region 530021, P.R. China.
College of Pharmacy, Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region 530021, P.R. China.
Int J Oncol. 2021 May;58(5). doi: 10.3892/ijo.2021.5199. Epub 2021 Mar 24.
At present, effective therapeutic drugs for triple‑negative breast cancer (TNBC) are lacking due to the absence of identified or available targets. Therefore, the present study aimed to identify key molecular targets and a specific targeted therapeutic drug to aid with the development of novel therapeutic strategies for TNBC. Based on the high expression of EGFR and Rac1 in TNBC and inspired by a novel antitumor strategy termed combi‑targeting, novel anthraquinone‑quinazoline hybrid 7B was synthesized to simultaneously target EGFR and Rac1. It was hypothesized that hybrid 7B may possess enhanced potency compared with its parent compounds. Breast cancer cell viability was detected by performing MTT assays. Flow cytometry was conducted to detect the effects of hybrid 7B on the cell cycle, apoptosis and the mitochondrial outer membrane potential. Ultrastructural alterations were observed by transmission electron microscopy. Cell invasion and migration were assessed by performing Transwell and wound‑healing assays, respectively. The expression levels of epithelial‑mesenchymal transition (EMT) markers and metastasis‑related proteins were detected by western blotting. Compared with Rhein and gefitinib, hybrid 7B displayed superior antiproliferative activity in MDA‑MB‑231 cells with an IC value of 2.31 M, which was 14‑fold higher compared with the EGFR tyrosine kinase inhibitor gefitinib. Further experiments demonstrated that hybrid 7B significantly reduced the mitochondrial membrane potential, enhanced MDA‑MB‑231 cell apoptosis and induced cell cycle arrest at the G/M phase compared with the control group. Typical morphological alterations of apoptotic cells were observed in hybrid 7B‑treated MDA‑MB‑231 and MCF‑7 cells. Compared with the control group, hybrid 7B significantly inhibited MDA‑MB‑231 cell invasion and migration by downregulating Rac1, EGFR, matrix metalloproteinases, snail family transcriptional repressor 1, Vimentin and β‑catenin protein expression levels, and upregulating E‑cadherin protein expression levels. The present study demonstrated that hybrid 7B inhibited TNBC cell migration and invasion by reversing EMT and targeting EGFR and Rac1; therefore, hybrid 7B may serve as a promising therapeutic agent for TNBC.
目前，由于缺乏明确或可用的靶点，三阴性乳腺癌（TNBC）缺乏有效的治疗药物。因此，本研究旨在确定关键的分子靶点和特定的靶向治疗药物，以帮助开发 TNBC 的新治疗策略。基于 EGFR 和 Rac1 在 TNBC 中的高表达，并受到一种称为联合靶向的新型抗肿瘤策略的启发，合成了新型蒽醌-喹唑啉杂合体 7B，以同时靶向 EGFR 和 Rac1。假设杂合体 7B 可能比其母体化合物具有更强的效力。通过 MTT 法检测乳腺癌细胞活力。通过流式细胞术检测杂合体 7B 对细胞周期、细胞凋亡和线粒体膜电位的影响。通过透射电子显微镜观察超微结构改变。通过 Transwell 和划痕愈合试验分别评估细胞侵袭和迁移。通过 Western blot 检测上皮-间充质转化（EMT）标志物和转移相关蛋白的表达水平。与大黄酸和吉非替尼相比，杂合体 7B 在 MDA-MB-231 细胞中表现出优越的增殖抑制活性，IC 值为 2.31μM，是 EGFR 酪氨酸激酶抑制剂吉非替尼的 14 倍。进一步的实验表明，与对照组相比，杂合体 7B 显著降低了线粒体膜电位，增强了 MDA-MB-231 细胞凋亡，并诱导细胞周期停滞在 G/M 期。在杂合体 7B 处理的 MDA-MB-231 和 MCF-7 细胞中观察到典型的凋亡细胞形态改变。与对照组相比，杂合体 7B 通过下调 Rac1、EGFR、基质金属蛋白酶、锌指转录因子家族 1、波形蛋白和β-连环蛋白蛋白表达水平，上调 E-钙黏蛋白蛋白表达水平，显著抑制 MDA-MB-231 细胞的侵袭和迁移。本研究表明，杂合体 7B 通过逆转 EMT 并靶向 EGFR 和 Rac1 抑制 TNBC 细胞迁移和侵袭；因此，杂合体 7B 可能成为 TNBC 的一种有前途的治疗药物。
