HIF - 1α as a marker of risk assessment for malignant transformation in oral submucous fibrosis: An immunohistochemical study.

Background: Oral submucous fibrosis (OSMF) is a potentially malignant disorder associated with habit of chewing betel quid containing arecanut. Morphological features of OSMF especially fibrosis suggests a possibility of the hypoxic environment in diseased tissues. The adaptation of cells to hypoxia appears to be mediated via hypoxia inducible factor-1α (HIF-1α) which is also said to be associated with malignant transformation of epithelial cells in various other carcinomas like prostate and cervical carcinoma. Therefore, the main objective of this study was to investigate the role of HIF-1α in progression and malignant transformation of OSMF. Materials and Methods: The study group consisted of histo-pathologically diagnosed 30 cases of oral submucous fibrosis and 10 cases of OSCC were taken as control. The immunohistochemistry was carried out on neutral buffered formalin-fixed paraffin-embedded tissue sections by using the monoclonal antibody of HIF-1α. Statistical analysis was done using SPSS software version 2.0. Results: A gradual and significant rise in the expression of HIF-1α was observed in various grades of OSMF and OSCC cases. HIF 1α expression was increased in cases showing hylanization and constricted blood vessels. A cut off value of 39.6% of HIF-1α positive cells was determined statistically to categorize the cases into high risk and low risk group for malignant transformation. Conclusion: Overexpression of HIF-1α may contribute to the progression and malignant transformation of OSMF. Cases expressing more than 40% of HIF-1α positive cells are at a greater risk for malignant transformation.

Quantitative assessment of CD15 positive tissue eosinophils in Oral Squamous Cell Carcinoma: effects on mast cells and tumor angiogenesis.

BACKGROUND: The present study determines to correlate eosinophil, mast cell and microvessel densities with the histopathological grades and clinical staging of Oral Squamous Cell Carcinoma (OSCC) cases, as the potential role of inflammatory mediators within tumor stroma remains debatable. METHODS: The study sample comprised 60 cases consisting of 40 cases of Well to moderately differentiated OSCC (group 1) and 20 cases of poorly differentiated OSCC (group 2). Immunohistochemistry with anti-CD15 antibody and antifactor VIII antibody; and toluidine blue special stain were employed for the detection of eosinophils, microvessels, and mast cells, respectively. RESULTS: The mean numbers of eosinophils, mast cells, and microvessels per high power field in group 1 and group 2 were 15.37±11.86 and 12.62±14.30, 6.00±4.84 and 4.51±4.51, 13.96±6.25 and 6.62±2.05, respectively. Eosinophil density had a positive correlation with both mast cell and microvessel density. Also, the correlation of primary tumor size (T status) with microvessel density was found to be statistically significant (P≤0.05). CONCLUSIONS: The cohesive interpretation of the aforementioned mediators in OSCC suggested that while these variables correlate well with the differentiation of tumor, the quantification did not correlate with the clinical staging of the disease.