Connecting cyto-nano-architectural attributes and epithelial molecular expression in oral submucous fibrosis progression to cancer.

OBJECTIVE: Problems in pre-cancer diagnosis complicate cancer theragnosis as well as life expectancy. There is uncertainty regarding malignant transformation of oral submucous fibrosis (OSF), an oral pre-cancer with dysplastic (OSFWD) and non-dysplastic (OSFWT) subtypes. Understanding the structural, molecular and physical aspects of epithelial homeostasis may be useful.

MATERIALS AND METHODS: Histopathological grading of biopsy sections was performed using H&E staining. Alterations in epithelial surface architecture in different groups was evaluated using scanning electron microscopy (SEM). The expression of crucial epithelial genes (p63, CK-5/6, CK-10, E-cadherin and β-catenin) was studied by immunohistochemistry, Western blot and RT-PCR analysis.

RESULTS: SEM observations revealed that the surface epithelial ridge pattern became thick and dense, and pit pattern gradually decreased in OSFWD and oral squamous cell carcinoma (OSCC). p63, ΔNp63 and CK-5/6 were up-regulated in OSFWD and OSCC but down-regulated in OSFWT. CK-10 was down-regulated in OSFWD compared to OSFWT. Cytoplasmic expression of E-cadherin and β-catenin was elevated in dysplastic and cancerous conditions. Moreover, statistical correlation between SEM features (ridges and pits) and molecular attributes demonstrated a significant positive relationship between the ridge-to-pit ratio and p63 population density (r=0.85) and the ridge-to-pit ratio and CK-5/6 intensity (r=0.63).

CONCLUSIONS: Molecular changes related to epithelial progressive maturation and cellular proliferation are correlated with concomitant alteration of epithelial surface architecture which helps to predict the malignant potentiality of OSF.