Immunohistochemical Evaluation of Epstein-Barr Virus Encoded Latent Membrane Protein-1 (Lmp-1) In Oral Epithelial Dysplasia and Oral Squamous Cell Carcinoma”

Abstract

BACKGROUND:
Oral cancer, ranking 16th globally, is linked to tobacco use and viral infections. Viral infections, especially by HPV and herpes group viruses, are significant risk factors of Oral squamous cell carcinoma (OSCC). Oncogenic viruses infect without killing host cells, often evading immune responses and establishing long-term infections. Early Diagnosis and treatment of precursors can prevent malignancy. Epstein-Barr Virus Latent Membrane Protein-1 (EBV LMP1) protein is of particular interest as a Potential biomarker for early malignant transformation of Oral Epithelial Dysplasia (OED) and therapeutic target in oral cancer due to its ability to alter cell behaviour and mimic CD40. Studies on LMP-1 expression in OED and OSCC are scarce and remain obscure. This study aimed to evaluate the expression of LMP-1 in OED and OSCC.

MATERIAL & METHODS:
Immunohistochemistry was used to evaluate the expression of LMP-1 in formalin fixed paraffin-embedded embedded tissue blocks from 17 histopathologically confirmed cases of oral epithelial dysplasia (OED), oral squamous cell carcinoma (OSCC), and normal oral mucosa (NOM). In each case, the number of positive cells was tallied out of a total of 1000 cells. The percentage of positive cells was measured. A mean percentage of positive cells was calculated, which was used to compare the groups.

RESULT:
The mean percentage of EBV LMP-1-positive cells in OED was 17.21±10.45 (mean±SD), OSCC was 60.38±11.18 (mean±SD), and in NOM it was 4.75±3.39 (mean±SD). The mean percentage of EBV LMP1 expression in OED, OSCC, and NOM when compared using one-way analysis of variance (ANOVA) indicated a statistically significant difference between and within the groups with a p value of 0.0001. Pairwise comparison of 3 groups with a mean percentage of EBV LMP-1 positive cells using the Tukey multiple post-hoc procedure indicated a statistically significant difference between OED vs. OSCC (p = 0.0001) and OSCC vs. NOM (p = 0.0001). EBV LMP1 expression showed a significant increase from normal oral mucosa (NOM) to oral epithelial dysplasia (OED) to oral squamous cell carcinoma (OSCC).

CONCLUSION:
The present study demonstrated elevated levels of EBV LMP1 as disease progressed from oral epithelial dysplasia (OED) to oral squamous cell carcinoma (OSCC), suggesting its involvement in the advancement of cancer. These findings suggest EBV LMP1’s potential as a marker to differentiate OED from OSCC. However, more study with a larger sample size is required to conclude on its utility to be used as a marker to differentiate OED from OSCC.