Bingham Victoria, Ong Chee Wee, James Jacqueline, Maxwell Pamela, Waugh David, Salto-Tellez Manuel, McQuaid Stephen
Molecular Pathology Programme, Centre for Cancer Research and Cell Biology, Queen's University, Belfast, UK BT9 7AE.
Prostate Cancer Research Group, Centre for Cancer Research and Cell Biology, Queen's University, Belfast, UK BT9 7AE.
Hum Pathol. 2016 Jan;47(1):95-103. doi: 10.1016/j.humpath.2015.09.009. Epub 2015 Sep 25.
Immunohistochemical staining for phosphatase and tensin homolog (PTEN) does not have either an acceptable standard protocol or concordance of scoring between pathologists. Evaluation of PTEN mRNA with a unique and verified sequence probe may offer a realistic alternative providing a robust and reproducible protocol. In this study, we have evaluated an in situ hybridization (ISH) protocol for PTEN mRNA using RNAScope technology and compared it with a standard protocol for PTEN immunohistochemistry (IHC). PTEN mRNA expression by ISH was consistently more sensitive than PTEN IHC, with 56% of samples on a mixed-tumor tissue microarray (TMA) showing high expression by ISH compared with 42% by IHC. On a prostate TMA, 49% of cases showed high expression by ISH compared with 43% by IHC. Variations in PTEN mRNA expression within malignant epithelium were quantifiable using image analysis on the prostate TMAs. Within tumors, clear overexpression of PTEN mRNA on malignant epithelium compared with benign epithelium was frequently observed and quantified. The use of SpotStudio software in the mixed-tumor TMA allowed for clear demonstration of varying levels of PTEN mRNA between tumor samples by the mRNA methodology. This was evident by the quantifiable differences between distinct oropharyngeal tumors (up to 3-fold increase in average number of spots per cell between 2 cases). mRNA detection of PTEN or other biomarkers, for which optimal or standardized immunohistochemical techniques are not available, represents a means by which heterogeneity of expression within focal regions of tumor can be explored with more confidence.
磷酸酶和张力蛋白同源物（PTEN）的免疫组织化学染色既没有可接受的标准方案，病理学家之间的评分也不一致。使用独特且经过验证的序列探针评估PTEN mRNA可能提供一种切实可行的替代方法，从而提供一种可靠且可重复的方案。在本研究中，我们评估了使用RNAScope技术检测PTEN mRNA的原位杂交（ISH）方案，并将其与PTEN免疫组织化学（IHC）的标准方案进行了比较。ISH检测的PTEN mRNA表达始终比PTEN IHC更敏感，在混合肿瘤组织微阵列（TMA）上，56%的样本ISH显示高表达，而IHC为42%。在前列腺TMA上，49%的病例ISH显示高表达，而IHC为43%。使用前列腺TMA的图像分析可量化恶性上皮内PTEN mRNA表达的差异。在肿瘤内，经常观察到并量化恶性上皮与良性上皮相比PTEN mRNA的明显过表达。在混合肿瘤TMA中使用SpotStudio软件可以通过mRNA方法清楚地展示肿瘤样本之间PTEN mRNA的不同水平。这在不同的口咽肿瘤之间的可量化差异中很明显（2例之间每个细胞的平均斑点数增加了3倍）。对于没有最佳或标准化免疫组织化学技术的PTEN或其他生物标志物的mRNA检测，是一种可以更有信心地探索肿瘤局部区域内表达异质性的方法。
