Unravelling hypoxia's role in oral cancer progression: Analysing HIF-1α and HIF-2α in epithelial dysplasia immunohistochemically.

Abstract

Background: In the world, oral squamous cell carcinoma is a leading cause of mortality and morbidity. Numerous factors are known to influence the tumour microenvironment, promoting the development of neoplasms. Among them, hypoxia plays a crucial role in neo-angiogenesis by stimulating factors that are proangiogenic in order to thrive with an adequate supply of blood, thereby increasing tumour aggressiveness and worsening the prognosis in neoplasms. Oral cancer is most often preceded by OPMDs with a histological connotation of epithelial dysplasia.

Aim and objective: The aim is to assess the expression of HIF-1α and HIF-2α in various grades of epithelial dysplasia and normal buccal mucosa, which will aid in comprehending the mechanism of malignant conversion of OPMD.

Methodology: Assessment of HIF-1α and HIF-2α expression was done in 90 samples of epithelial dysplasia, which were categorised histologically into 30 samples each of mild, moderate and severe dysplasia immunohistochemically.

Results: A statistically significant difference was noted between expression of HIF-1 alpha and HIF-2 alpha in each mild (0.133 ± 0.098 and 0.014 ± 0.008, respectively), moderate (2.050 ± 0.530 and 1.200 ± 0.406, respectively) and severe grades of dysplasia (6.350 ± 0.939 and 2.400 ± 0.674, respectively). (P = 0.001, P = 0.002, P = 0.001, respectively).

Conclusion: Hypoxia is a crucial factor that triggers the switch of angiogenesis and other inflammatory mediators, facilitating tumorigenesis. This is essential for anticipating the malignant conversion of epithelial dysplasia and, in turn, also predicts the prognosis.