Institute of Analytical Chemistry and Radiochemistry, CCB - Center for Chemistry and Biomedicine, Leopold-Franzens University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria; Institute of Legal Medicine, Innsbruck Medical University, Muellerstraße 44, 6020 Innsbruck, Austria.
J Proteomics. 2013 Oct 8;91:500-14. doi: 10.1016/j.jprot.2013.08.003. Epub 2013 Aug 14.
New biomarkers are needed to improve the specificity of prostate cancer detection and characterisation of individual tumors. In a proteomics profiling approach using MALDI-MS tissue imaging on frozen tissue sections, we identified discriminating masses. Imaging analysis of cancer, non-malignant benign epithelium and stromal areas of 15 prostatectomy specimens in a test and 10 in a validation set identified characteristic m/z peaks for each tissue type, e.g. m/z 10775 for benign epithelial, m/z 6284 and m/z 6657.5 for cancer and m/z 4965 for stromal tissue. A 10-fold cross-validation analysis showed highest discriminatory ability to separate tissue types for m/z 6284 and m/z 6657.5, both overexpressed in cancer, and a multicomponent mass peak cluster at m/z 10775-10797.4 overexpressed in benign epithelial tissue. ROC AUC values for these three masses ranged from 0.85 to 0.95 in the discrimination of malignant and non-malignant tissue. To identify the underlying proteins, prostate whole tissue extract was separated by nano-HPLC and subjected to MALDI TOF/TOF analysis. Proteins in fractions containing discriminatory m/z masses were identified by MS/MS analysis and candidate marker proteins subsequently validated by immunohistochemistry (IHC). Biliverdin reductase B (BLVRB) turned out to be overexpressed in PCa tissue.
In this study on cryosections of radical prostatectomies of prostate cancer patients, we performed a MALDI-MS tissue imaging analysis and a consecutive protein identification of significant m/z masses by nano-HPLC, MALDI TOF/TOF and MS/MS analysis. We identified BLVRB as a potential biomarker in the discrimination of PCa and benign tissue, also suggesting BVR as a feasible therapeutic target.
为了提高前列腺癌检测的特异性和个体肿瘤的特征,需要新的生物标志物。在使用 MALDI-MS 组织成像对冷冻组织切片进行的蛋白质组学分析中,我们鉴定出了有区别的物质。在测试组的 15 个前列腺切除术标本和验证组的 10 个标本中,对癌症、非恶性良性上皮和基质区域进行成像分析,确定了每种组织类型的特征 m/z 峰,例如良性上皮的 m/z 10775、癌症的 m/z 6284 和 m/z 6657.5 以及基质组织的 m/z 4965。十重交叉验证分析显示,m/z 6284 和 m/z 6657.5 对区分癌症和非恶性组织具有最高的辨别能力,这两个峰都在癌症中过度表达,而在良性上皮组织中过度表达的 m/z 10775-10797.4 的多组分质量峰簇。这三个物质的 ROC AUC 值在区分恶性和非恶性组织时,范围在 0.85 到 0.95 之间。为了鉴定潜在的蛋白质,通过纳诺 HPLC 分离前列腺全组织提取物,并进行 MALDI-TOF/TOF 分析。通过 MS/MS 分析鉴定含有有区别的 m/z 质量的馏分中的蛋白质,并通过免疫组织化学(IHC)随后验证候选标记蛋白。胆红素还原酶 B(BLVRB)在 PCa 组织中过度表达。
在这项对前列腺癌患者根治性前列腺切除术的冷冻切片的研究中,我们进行了 MALDI-MS 组织成像分析,并通过纳诺 HPLC、MALDI-TOF/TOF 和 MS/MS 分析对有意义的 m/z 质量进行连续的蛋白质鉴定。我们鉴定出 BLVRB 是区分 PCa 和良性组织的潜在生物标志物,这也表明 BVR 是一个可行的治疗靶点。