Association of acute phase protein-haptoglobin, and epithelial-mesenchymal transition in buccal cancer: a preliminary report.

Background: The aim of this study was to determine the influence of inflammation on acute phase protein and epithelial-mesenchymal transition (EMT) in buccal cancer. Methods: Western blotting was carried out to investigate the expression of haptoglobin and epithelial-mesenchymal transition in oral cancer cell lines with or without IL-6 stimulation. We studied patients with buccal cancer patients without distant metastasis at diagnosis. Correlation between cellular haptoglobin, EMT, and clinical characteristics of buccal cancer was analyzed to assess the prognostic value of cellular haptoglobin level and EMT. The relationship of haptoglobin, and EMT expression with survival was assessed using Cox proportional hazard models. Results: Western blotting analysis showed that increased haptoglobin protein was associated with overexpression of vimentin. Under IL-6 stimulation, overexpression of haptoglobin, EMT-associated motile phenotype was noted in OC2 cell lines. Overexpression of haptoglobin was also associated with an increased risk for locoregional recurrence [hazard ratio (HR) 1.04; p=0.011] after adjusting for age, gender, disease site, stage, and treatment modality. Conclusions: Increased cellular expression of haptoglobin is associated with EMT in oral cancer cell lines and this phenomenon could be exaggerated with IL-6. Cellular expression of haptoglobin is related to locoregional recurrence rate in buccal cancer patients. [ABSTRACT FROM AUTHOR]