Abstract:
Introduction: Breast cancer (BC) diagnostics lack noninvasive methods and procedures for screening and monitoring disease dynamics. Admitted CellSearch® is used for fluid biopsy and capture of circulating tumor cells of only epithelial origin. Here we describe an RNA aptamer (MDA231) for detecting BC cells in clinical samples, including blood. The MDA231 aptamer was originally selected against triple-negative breast cancer cell line MDA-MB-231 using cell-SELEX. Methods: The aptamer structure in solution was predicted using mFold program and molecular dynamic simulations. The affinity and specificity of the evolved aptamers were evaluated by flow cytometry and laser scanning microscopy on clinical tissues from breast cancer patients. CTCs were isolated form the patients\' blood using the developed method of aptamer-based magnetic separation. Breast cancer origin of CTCs was confirmed by cytological, RT-qPCR and Immunocytochemical analyses. Results: MDA231 can specifically recognize breast cancer cells in surgically resected tissues from patients with different molecular subtypes: triple-negative, Luminal A, and Luminal B, but not in benign tumors, lung cancer, glial tumor and healthy epithelial from lungs and breast. This RNA aptamer can identify cancer cells in complex cellular environments, including tumor biopsies (e.g., tumor tissues vs. margins) and clinical blood samples (e.g., circulating tumor cells). Breast cancer origin of the aptamer-based magnetically separated CTCs has been proved by immunocytochemistry and mammaglobin mRNA expression. Discussion: We suggest a simple, minimally-invasive breast cancer diagnostic method based on non-epithelial MDA231 aptamer-specific magnetic isolation of circulating tumor cells. Isolated cells are intact and can be utilized for molecular diagnostics purposes.
摘要:
简介:乳腺癌(BC)诊断缺乏筛查和监测疾病动态的非侵入性方法和程序。接受的CellSearch®用于流体活检和捕获仅上皮来源的循环肿瘤细胞。在这里,我们描述了一种用于检测临床样品中BC细胞的RNA适体(MDA231),包括血.最初使用细胞-SELEX针对三阴性乳腺癌细胞系MDA-MB-231选择MDA231适体。方法:利用mFold程序和分子动力学模拟预测溶液中的适体结构。通过流式细胞术和激光扫描显微镜对乳腺癌患者的临床组织评估了进化适体的亲和力和特异性。使用开发的基于适体的磁分离方法从患者血液中分离CTC。通过细胞学证实了CTC的乳腺癌起源,RT-qPCR和免疫细胞化学分析。结果:MDA231可以特异性识别不同分子亚型患者手术切除组织中的乳腺癌细胞:三阴性,管腔A,和管腔B,但不是良性肿瘤,肺癌,胶质肿瘤和健康的肺和乳腺上皮。这种RNA适体可以在复杂的细胞环境中识别癌细胞,包括肿瘤活检(例如,肿瘤组织vs.边缘)和临床血液样本(例如,循环肿瘤细胞)。基于适体的磁性分离CTC的乳腺癌起源已通过免疫细胞化学和乳腺球蛋白mRNA表达得到证明。讨论:我们建议一个简单的,基于非上皮MDA231适体特异性循环肿瘤细胞磁分离的微创乳腺癌诊断方法.分离的细胞是完整的并且可用于分子诊断目的。