Matta Ajay, DeSouza Leroi V, Shukla Nootan Kumar, Gupta Siddhartha D, Ralhan Ranju, Siu K W Michael
Department of Biochemistry, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India.
J Proteome Res. 2008 May;7(5):2078-87. doi: 10.1021/pr7007797. Epub 2008 Apr 12.
Diagnostic oncoproteomics is an emerging field; at present, studies on evaluation of prognostic utility of potential biomarkers identified using proteomic techniques are limited. Analysis with isobaric mass tags (iTRAQ) by multidimensional liquid chromatography-mass spectrometry (LC-MS/MS) to identify proteins that are differentially expressed in human head-and-neck/oral squamous cell carcinomas (HNOSCCs) versus noncancerous head-and-neck tissues has led to the discovery, identification, and verification of consistently increased expression of a panel of proteins, including stratifin (14-3-3sigma) and YWHAZ (14-3-3zeta), that may serve as potential cancer biomarkers. Herein, we describe the prognostic utility of these two candidate biomarkers for head-and-neck/oral squamous cell carcinoma (HNOSCC). To determine the clinical significance of stratifin and YWHAZ in head-and-neck tumorigenesis, the expressions of these two proteins were analyzed in HNOSCCs (51 cases) and nonmalignant tissues (39 cases) using immunohistochemistry. Significant increase in stratifin expression was observed in the HNOSCCs as compared to the nonmalignant mucosa [p=0.003, Odd's Ratio (OR)=3.8, 95% CI=1.6-9.2]. Kaplan-Meier survival analysis reveals correlation of stratifin overexpression with reduced disease-free survival of HNOSCC patients (p=0.06). The most intriguing finding is the significant decrease in median disease-free survival (13 months) in HNOSCC patients showing overexpression of both stratifin and YWHAZ proteins, as compared to patients that did not show overexpression of these proteins (median disease-free survival=38 months, p=0.019), underscoring their utility as adverse prognosticators for HNOSCCs. Co-immunoprecipitation assays show the formation of stratifin-YWHAZ heterodimers in HNOSCC cells and tissue samples, and interactions with NFkappaB, beta-catenin, and Bcl-2 proteins. These results suggest the involvement of these proteins in the development of head-and-neck cancer and their association with adverse disease outcome.
诊断肿瘤蛋白质组学是一个新兴领域；目前，关于评估使用蛋白质组学技术鉴定出的潜在生物标志物的预后效用的研究有限。通过多维液相色谱 - 质谱联用（LC - MS/MS）的等压质量标签（iTRAQ）分析，以鉴定在人类头颈部/口腔鳞状细胞癌（HNOSCC）与非癌性头颈部组织中差异表达的蛋白质，这导致发现、鉴定并验证了一组蛋白质的表达持续增加，包括层粘连蛋白（14 - 3 - 3σ）和YWHAZ（14 - 3 - 3ζ），它们可能作为潜在的癌症生物标志物。在此，我们描述这两种候选生物标志物对头颈部/口腔鳞状细胞癌（HNOSCC）的预后效用。为了确定层粘连蛋白和YWHAZ在头颈部肿瘤发生中的临床意义，使用免疫组织化学分析了这两种蛋白质在51例HNOSCC和39例非恶性组织中的表达。与非恶性黏膜相比，在HNOSCC中观察到层粘连蛋白表达显著增加[p = 0.003，优势比（OR）= 3.8，95%置信区间= 1.6 - 9.2]。Kaplan - Meier生存分析显示层粘连蛋白过表达与HNOSCC患者无病生存期缩短相关（p = 0.06）。最引人注目的发现是，与未显示这些蛋白质过表达的患者相比（无病生存期中位数= 38个月，p = 0.019），同时显示层粘连蛋白和YWHAZ蛋白过表达的HNOSCC患者的无病生存期中位数显著缩短（13个月）。这突出了它们作为HNOSCC不良预后指标的效用。免疫共沉淀分析显示在HNOSCC细胞和组织样本中层粘连蛋白 - YWHAZ异二聚体的形成，以及与NFκB、β - 连环蛋白和Bcl - 2蛋白的相互作用。这些结果表明这些蛋白质参与了头颈部癌症的发展及其与不良疾病结局的关联。
