Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.
PLoS One. 2010 May 3;5(5):e10441. doi: 10.1371/journal.pone.0010441.
Biomarkers play a key role in risk assessment, assessing treatment response, and detecting recurrence and the investigation of multiple biomarkers may also prove useful in accurate prediction and prognosis of cancers. Immunohistochemistry (IHC) has been a major diagnostic tool to identify therapeutic biomarkers and to subclassify breast cancer patients. However, there is no suitable IHC platform for multiplex assay toward personalized cancer therapy. Here, we report a microfluidics-based multiplexed IHC (MMIHC) platform that significantly improves IHC performance in reduction of time and tissue consumption, quantification, consistency, sensitivity, specificity and cost-effectiveness.
METHODOLOGY/PRINCIPAL FINDINGS: By creating a simple and robust interface between the device and human breast tissue samples, we not only applied conventional thin-section tissues into on-chip without any additional modification process, but also attained perfect fluid control for various solutions, without any leakage, bubble formation, or cross-contamination. Four biomarkers, estrogen receptor (ER), human epidermal growth factor receptor 2 (HER2), progesterone receptor (PR) and Ki-67, were examined simultaneously on breast cancer cells and human breast cancer tissues. The MMIHC method improved immunoreaction, reducing time and reagent consumption. Moreover, it showed the availability of semi-quantitative analysis by comparing Western blot. Concordance study proved strong consensus between conventional whole-section analysis and MMIHC (n = 105, lowest Kendall's coefficient of concordance, 0.90). To demonstrate the suitability of MMIHC for scarce samples, it was also applied successfully to tissues from needle biopsies.
CONCLUSIONS/SIGNIFICANCE: The microfluidic system, for the first time, was successfully applied to human clinical tissue samples and histopathological diagnosis was realized for breast cancers. Our results showing substantial agreement indicate that several cancer-related proteins can be simultaneously investigated on a single tumor section, giving clear advantages and technical advances over standard immunohistochemical method. This novel concept will enable histopathological diagnosis using numerous specific biomarkers at a time even for small-sized specimens, thus facilitating the individualization of cancer therapy.
生物标志物在风险评估、评估治疗反应以及检测复发方面发挥着关键作用，对多个生物标志物的研究也可能有助于癌症的准确预测和预后。免疫组织化学（IHC）一直是识别治疗生物标志物和对乳腺癌患者进行亚分类的主要诊断工具。然而，目前尚没有适用于个性化癌症治疗的多重 IHC 检测的平台。在此，我们报告了一种基于微流控的多重免疫组织化学（MMIHC）平台，该平台通过减少时间和组织消耗、量化、一致性、灵敏度、特异性和成本效益，显著提高了 IHC 的性能。
方法/主要发现：通过在设备和人乳腺癌组织样本之间创建一个简单而强大的接口，我们不仅将传统的薄切片组织直接应用于芯片上，而无需任何额外的修饰过程，而且还实现了对各种溶液的完美流体控制，没有任何泄漏、气泡形成或交叉污染。在乳腺癌细胞和人乳腺癌组织上同时检测了四种生物标志物，即雌激素受体（ER）、人表皮生长因子受体 2（HER2）、孕激素受体（PR）和 Ki-67。MMIHC 方法改善了免疫反应，减少了时间和试剂的消耗。此外，通过与 Western blot 进行比较，它还显示了半定量分析的可用性。一致性研究证明了传统全切片分析与 MMIHC 之间的强烈一致性（n = 105，最低肯德尔协和系数为 0.90）。为了证明 MMIHC 适用于稀缺样本，它还成功地应用于针吸活检组织。
结论/意义：微流控系统首次成功应用于人临床组织样本，并实现了对乳腺癌的组织病理学诊断。我们的研究结果表明，几种癌症相关蛋白可以同时在单个肿瘤切片上进行研究，与标准免疫组织化学方法相比具有明显的优势和技术进步。这一新颖的概念将使组织病理学诊断能够同时使用多个特定的生物标志物，即使对于小样本也能实现，从而促进癌症治疗的个体化。
