N-acetylneuraminic acid: A scrutinizing tool in oral squamous cell carcinoma diagnosis

BACKGROUND: Oral cancer has one of the highest mortality rate among other malignancies. An attempt has been made to assess the genetic expression of a cell surface glycoprotein component - sialic acid released by the malignant cells which will reflect on the oral squamous cell carcinoma (OSCC). The aim of this study was to estimate and correlate the salivary and serum sialic acid levels in OSCC. MATERIALS AND METHODS: In our case–control study, saliva and blood samples were obtained from Group 1 - 10 healthy controls, Group 2 - 12 well-differentiated OSCC, Group 3 - 7 moderately differentiated and 2 poorly differentiated OSCC. Serum and salivary total sialic acid levels were analyzed by Warren's thiobarbituric acid method and acidic ninhydrin method, respectively. The results were analyzed statistically by Student's t-test and Pearson's correlation coefficient (P ≤ 0.05). RESULTS: A significant difference in the serum and salivary sialic acid levels was observed between Group 1 and Group 3 (P = 0.01 and < 0.0001) and in salivary sialic acid between Group 2 and Group 3 (P = 0.02). A significant positive correlation was observed between salivary and serum sialic acid in Groups 2 and 3 together (P = 0.015). CONCLUSION: As the histopathological grade progresses, there is a marked increase in level of sialic acid. There is a significant positive correlation between serum and salivary sialic acid levels in OSCC. Further research with larger sample size along with grading and staging system may highlight its significance in OSCC.