MUC4 Expression in Oral Dysplastic Epithelium and Oral Squamous Cell Carcinoma: An Immunohistochemical Study

MUCIN4 (MUC4) glycosylation is linked to the oncogenesis and progression of a neoplastic process. It can suggest information pertaining to tumor progression, management and its natural properties. Thus, MUC4 can play a pivotal role in prognostic diagnosis. This study aimed to analyze the MUC4 expression in oral cell squamous carcinoma and oral dysplastic epithelium.

The research included 45 samples of oral epithelial dysplasia (OED) and 45 cases of oral squamous cell carcinoma (OSCC). In order to carry out the investigation, tissue blocks of previously diagnosed cases of OED and OSCC were retrieved from the relevant archives. Forty-five OED cases were categorized into three group's mild, moderate and severe dysplasia, with 15 cases in each respective category. Forty-five OSCC cases were categorized into three groups: well differentiated, moderately differentiated, and poorly differentiated OSCC with 15 cases in each respective category. Ten tissue biopsies of normal oral mucosa were obtained from subjects in the control group. The chi-square test and one-way ANOVA were used for statistical analysis.

There was an absence of MUC4 expression in normal mucosa, whereas the OED and OSCC groups had a significant amount of observable variance. Within the OED category of cases, a consistent progression from mild to severe dysplasia was seen in terms of the staining pattern. Cases with severe dysplasia displayed a staining pattern that covered the complete thickness of the tissue in the epithelium. Expression of MUC4 was shown to be lower in moderate differentiated squamous cell carcinoma (MDSCC), and poorly differentiated squamous cell carcinoma (PDSCC) as compared to well differentiated squamous cell carcinoma (WDSCC). It showed decreasing pattern across all grades of OSCC. In WDSCC, an intense highest staining response was noticed, particularly among the cells that are highly differentiated and take the form of a honeycomb pattern.

Analysis of the expression profile of MUC4 and the aberrant expression of this gene in OSCC suggests that it may serve as a useful diagnostic marker. Therefore, it is possible to draw the conclusion that MUC4 plays a very significant part in the pathogenesis of OSCC and also acts as a marker that may be taken into consideration for the accurate diagnosis of OED and OSCC.