Identification of SCARA5 as a Potential Biomarker for Oral Squamous Cell Carcinoma using MALDI-TOF-MS Analysis.

PURPOSE: To find the potential biomarkers in the diagnostic model of oral and squamous cell carcinoma (OSCC), and to further validate the biomarker. EXPERIMENTAL DESIGN: With the MALDI-TOF-MS analysis between tissues from oral cancer patients and normal oral mucosa from healthy controls, scavenger receptor class A member 5 (scara5) is found to be potentially significant after searching the protein database. In addition, Immunohistochemical staining, PCR, ELISA, and Western blot technique are used to detect scara5 expression in clinical samples and cell lines. RESULTS: In this study, the results indicate that scara5 expression is decreased in tumor group in the MALDI-TOF-MS analysis. Furthermore, down-regulation of scara5 expression is related with cell proliferation and invasion. Serum scara5 detection can discriminate OSCC samples from normal samples with high sensitivity. CONCLUSIONS AND CLINICAL RELEVANCE: Scara5 has the potential to be considered as a serum biomarker in the early diagnosis of OSCC. The clinical relevance of the study lies in finding the biomarker by proteomics and subsequently validating it with clinical samples and cell lines.