Molecular Grading of Oral Squamous Cell Carcinomas Infected with EBV

Area of Science:

• Oncology
• Virology
• Molecular Biology

Background:

• Squamous Cell Carcinoma (SCC) is a prevalent cancer in the head and neck, with viruses being key etiological factors.
• Viral infections can disrupt cellular proliferation and apoptosis regulators like p53, c-myc, and bcl-2.

Purpose of the Study:

• To determine the molecular grading of oral squamous cell carcinoma (OSCC) in patients infected with the Epstein-Barr Virus (EBV).
• To investigate the relationship between EBV infection and the expression of proliferation and apoptosis regulators.

Main Methods:

• Biopsies from 27 OSCC patients were analyzed for EBV infection using in situ hybridization (EBER) and immunohistochemistry (LMP-1, EBNA-1).
• Cell proliferation and apoptosis regulator expression (p53i, c-myc, bcl-2) were assessed via immunohistochemical analysis to establish molecular grades.

Main Results:

• The study identified a correlation where only EBV nuclear antigen-1 (EBNA-1) expression significantly affected inactive p53 (p53i) expression.
• A novel molecular grading system for EBV-infected OSCC was proposed, categorizing cases into Grade I (low), Grade II (medium), and Grade III (high) based on EBNA-1 and p53i expression levels.

Conclusions:

• In EBV-infected OSCC, EBNA-1 expression is the sole determinant influencing p53i expression.
• This finding suggests a specific molecular pathway in EBV-associated oral cancers that can be utilized for refined grading and potentially targeted therapies.