Quantitative proteogenomic characterization in MUC1 and MUC4 in oral squamous cell carcinoma, oral potentially malignant disorders, and normal oral mucosa in carcinogenesis

Mucins are glycoproteins with a significant molecular weight that have a diverse range of biological functions. MUC1 & MUC4 are transmembrane mucin family members that are expressed in airway epithelial cells and body fluids. It is expressed excessively in numerous carcinomas in addition to their altered expression. A thorough review of the literature reveals very limited research about MUC1 & 4 expressions in oral malignancies and oral premalignant disorders. The aim of the research is to assess the pattern and quantity of gene expression in MUC1 & MUC4 individually in various grades of oral squamous cell carcinoma (OSCC), oral premalignant disorders (OPMDs)- oral epithelial dysplasia (OED), oral submucous fibrosis (OSF), oral lichen planus (OLP), and compared with normal oral mucosa (NOM).

Immunohistochemistry and qRTPCR evaluation of MUC1 & 4 on sixty-three cases of OSCC, OPMD, and NOM was accomplished. The one-way ANOVA test and Chi-square test were done for statistical analysis.

The overall immunoexpression of MUC1 & 4 increased significantly from NOM to OPMDs to OSCC. In the subgrades of OSCC and OPMDs, the staining intensity varied. For MUC4, the intensity was strongest in well-differentiated grades and MUC1, exhibiting a higher expression in poorly differentiated grades of OSCC and OPMDs.

The study's results indicate that MUC1 & 4 individually are crucial for monitoring OSCC and OPMD pathogenesis as the former gives an idea of highly undifferentiated grades while the latter indicated more differentiated tumors and perhaps a better prognosis. Therefore, the two can be useful tumor markers for determining the severity and eliminating it in its early phases.