Department of Biomedical Engineering , University at Buffalo, The State University of New York , 332 Bonner Hall , Buffalo , New York 14260 , United States.
Department of Biostatistics , University at Buffalo, The State University of New York , 710 Kimball Tower , Buffalo , New York 14214 , United States.
ACS Appl Mater Interfaces. 2018 Dec 19;10(50):43375-43386. doi: 10.1021/acsami.8b13971. Epub 2018 Dec 6.
Tumor-derived exosomes (TEXs) play instrumental roles in tumor growth, angiogenesis, immune modulation, metastasis, and drug resistance. TEX RNAs are a new class of noninvasive biomarkers for cancer. Neither current techniques, such as quantitative reverse transcription polymerase chain reaction (qRT-PCR) and next-generation sequencing, nor new ones, such as electrochemical or surface plasmon resonance-based biosensors, are able to selectively capture and separate TEXs from normal cell-derived exosomes, making TEX RNAs potentially less sensitive biomarkers. We developed an immuno-biochip that selectively captures TEXs using antibodies against tumor-associated proteins and quantifies in situ TEX RNAs using cationic lipoplexes containing molecular beacons. We used the immuno-biochip to measure the expression of miR-21 microRNA and TTF-1 mRNA in EGFR- or PD-L1-bearing exosomes from human sera and achieved absolute sensitivity and specificity in distinguishing normal controls from non-small cell lung cancer patients. Our results demonstrated that the effective separation of TEXs from other exosomes greatly improved the detection sensitivity and specificity. Compared with the traditional immunomagnetic separation-RNA isolation-qRT-PCR workflow, the immuno-biochip showed superior lung cancer diagnostic performance, consumed less samples (∼30 μL), and shortened assay time from ∼24 to 4 h.
肿瘤来源的外泌体 (TEXs) 在肿瘤生长、血管生成、免疫调节、转移和耐药性中发挥重要作用。TEX RNA 是癌症的一类新型非侵入性生物标志物。目前的技术，如定量逆转录聚合酶链反应 (qRT-PCR) 和下一代测序，以及新的技术，如电化学或基于表面等离子体共振的生物传感器，都无法从正常细胞来源的外泌体中选择性地捕获和分离 TEXs，这使得 TEX RNA 作为潜在的生物标志物的敏感性降低。我们开发了一种免疫生物芯片，该芯片使用针对肿瘤相关蛋白的抗体选择性捕获 TEXs，并使用含有分子信标的阳离子脂质体原位定量 TEX RNA。我们使用免疫生物芯片测量了来自人血清的携带 EGFR 或 PD-L1 的外泌体中的 miR-21 微 RNA 和 TTF-1 mRNA 的表达水平，并在区分正常对照和非小细胞肺癌患者方面实现了绝对的敏感性和特异性。我们的结果表明，有效分离 TEXs 与其他外泌体大大提高了检测的敏感性和特异性。与传统的免疫磁分离-RNA 分离-qRT-PCR 工作流程相比，免疫生物芯片显示出优越的肺癌诊断性能，消耗的样本更少（约 30 μL），并且将检测时间从约 24 小时缩短至 4 小时。
