Identification of over-expressed proteins in oral squamous cell carcinoma (OSCC) patients by clinical proteomic analysis

BackgroundOral cancer is a worldwide problem. It is a universal aggressive disease in the population of smoking and drinking. The oral cancer mortality has been ranked 5th place in Taiwan in male cancer patients. A number of protein markers for oral cancer are still not applicable in large populations. Proteomic technologies provide excellent tools for rapid screening of a large number of potential biomarkers in malignant cells.MethodProteomics and real-time quantitative RT-PCR were used to analyze over-expressed proteins in 10 OSCC patients.ResultForty-one proteins were identified as commonly over-expressed in OSCC tissues. In OSCC tissues, αB-crystallin, tropomyosin 2, myosin light chain 1, heat shock protein 27 (HSP27), stratifin, thioredoxin-dependent peroxide reductase, flavin reductase, vimentin, rho GDP-dissociation inhibitor 2 (rho GDI-2), glutathione S-transferase Pi (GST-pi) and superoxide dismutase [Mn] (MnSOD) were significantly over-expressed (an average of 7.2, 6.0, 5.7, 4.3, 3.6, 3.4, 3.0, 3.0, 2.6, 2.5, 2.1-fold, respectively). In real-time quantitative RT-PCR analysis, the gene expressions of αB-crystallin, HSP27 and MnSOD were also increased in the cancer tissues, consistent with proteomic results.ConclusionThe identified proteins in this experiment may be used in future studies of carcinogenesis or as diagnostic markers and therapeutic targets for OSCC.