Copy Number Alteration of Cyclin D1 (CCND 1) Gene as a Prognostic Factor in Oral Squamous Cancers and its Correlation with Immunohistochemistry (IHC)

Background Oral squamous cancers remain the most common cancers among males in India and the third most common cancer among men and women combined, with an age standardized ratio of 9.1 per 100,000 population. Surgery and chemoradiation have not improved survival rates significantly and hence, newer therapeutic targets are needed. Cyclin D1 (CCND1) is a proto-oncogene which is located on chromosome 11q13 and has been found to be amplified in many cancers including oral cancers. It is said to correlate with aggressive tumor growth and a poorer prognosis. Aim This article correlates cyclin D1 (CCND1) gene copy number alteration with clinicopathologic prognostic factors in oral squamous cancers. Materials and Methods Sixty-three patients who underwent surgery for oral cancer between January and June 2022 were included in the study after obtaining informed consent and ethics approval. Copy number alteration of CCND1 was assessed using quantitative polymerase chain reaction (Qf PCR) and correlated with clinical and histopathological prognostic factors, including short-term recurrence. Statistical analysis was performed using the SPSS software. Results A statistically significant correlation was determined between the Qf PCR values of CCND1 gene and locoregional recurrence. Gene copy number alteration also correlated strongly with a higher grade of the primary tumor. There was also a significant correlation between the Qf PCR values and the immunohistochemistry for cyclin D1. Conclusion Cyclin D1 offers a new therapeutic target in oral cancers and may improve survival without significant treatment-related morbidity.