Park Soyeun
College of Pharmacy, Keimyung University, Daegu, Korea.
J Cancer Prev. 2018 Jun;23(2):87-92. doi: 10.15430/JCP.2018.23.2.87. Epub 2018 Jun 30.
The mechanical deformability of cancer cells has attracted particular attention as an emerging biomarker for the prediction of anti-cancer drug sensitivity. Nevertheless, it has not been possible to establish a general rubric for the identification of drug susceptibility in breast cancer cells from a mechanical perspective. In the present study, we investigated the mechanical alteration associated with resistance to adjuvant therapy in breast cancer cells.
We performed an 'atomic force microscopy (AFM)-based nanomechanical study' on 'drug-sensitive (MCF-7)' and 'drug-resistant (MCF-7/ADR)' breast cancer cells. We also conducted cell viability tests to evaluate the difference in doxorubicin responsiveness between two breast cancer cell lines. We carried out a wound closure experiment to investigate the motility changes associated with chemotherapeutic resistance. To elucidate the changes in molecular alteration that accompany chemotherapeutic resistance, we investigated the expression of vinculin and integrin-linked kinase-1-which are proteins involved in substrate adhesion and the actin cytoskeleton-using Western blotting analysis.
A MTT assay confirmed that the dose-dependent efficacy of doxorubicin was reduced in MCF-7/ADR cells compared to that in MCF-7 cells. The wound assay revealed enhanced two-dimensional motility in the MCF-7/ADR cells. The AFM mechanical assay showed evidence that the drug-resistant breast cancer cells exhibited a significant decrease in mechanical deformability compared to their drug-sensitive counterparts. The mechanical alteration in the MCF-7/ADR cells was accompanied by upregulated vinculin expression.
The obtained results manifestly showed that the altered mechanical signatures-including mechanical deformability and motility-were closely related with drug resistance in the breast cancer cells. We believe that this investigation has improved our understanding of the chemotherapeutic susceptibility of breast cancer cells.
癌细胞的机械变形能力作为一种预测抗癌药物敏感性的新兴生物标志物，已引起特别关注。然而，从机械角度建立一种识别乳腺癌细胞药物敏感性的通用标准仍未实现。在本研究中，我们调查了与乳腺癌细胞辅助治疗耐药性相关的机械改变。
我们对“药物敏感（MCF-7）”和“耐药（MCF-7/ADR）”乳腺癌细胞进行了“基于原子力显微镜（AFM）的纳米力学研究”。我们还进行了细胞活力测试，以评估两种乳腺癌细胞系对阿霉素反应性的差异。我们进行了伤口愈合实验，以研究与化疗耐药性相关的运动性变化。为了阐明伴随化疗耐药性的分子改变，我们使用蛋白质印迹分析研究了纽蛋白和整合素连接激酶-1（参与底物粘附和肌动蛋白细胞骨架的蛋白质）的表达。
MTT 分析证实，与 MCF-7 细胞相比，MCF-7/ADR 细胞中阿霉素的剂量依赖性疗效降低。伤口实验显示 MCF-7/ADR 细胞的二维运动性增强。AFM 力学分析表明，与药物敏感的乳腺癌细胞相比，耐药乳腺癌细胞的机械变形能力显著降低。MCF-7/ADR 细胞的机械改变伴随着纽蛋白表达上调。
获得的结果明显表明，包括机械变形能力和运动性在内的机械特征改变与乳腺癌细胞中的耐药性密切相关。我们相信这项研究增进了我们对乳腺癌细胞化疗敏感性的理解。
