The Role of Salivary Micro RNAs as a Diagnostic Marker in Early Detection of Oral Squamous Cell Carcinoma

OBJECTIVE: To assess the diagnostic role of salivary microRNA for early detection oforal squamous cell carcinoma and to compare the salivary microRNA with Biopsy in thediagnosis of oral squamous cell carcinoma.Methodology: The descriptive cross-sectional study was conducted in the department of pathology and molecular laboratory, department of oral & maxillofacial surgery of Liaquat University of Medical Health Sciences, Jamshoro / Hyderabad.Inclusion Criteria: All histopathologicaly diagnosed OSCC patients of both genders with age group 18 years and above will be included in the study after taking their informed consent.  Whole saliva samples (inactivated) were collectedfrom subjects diagnosed as OSCC and controls. The subjects were counseled to avoid eating, drinking, smoking or oral procedures for at least 1 h prior to the collection of saliva. Subjects are asked to rinse their mouth well with distilled drinking water for one minute before taking the saliva samples. After five minutes of oral rinsing spit 5 mL of saliva into a 50 mL sterile tube placed on the ice. The tube should remain on ice while collecting the saliva samples. Fourhundred microliters of the whole saliva mixture (200 ?L whole saliva and 200 ?L RNA later),and 400 ?L of the supernatant saliva was used for RNA extraction. Saliva samples wereextracted using the mirVana™ miRNA Isolation Kit according to the manufacturer's guideline(Ambion Inc., Austin, TX). Whole saliva samples were preserved with RN Alater (QIAGENInc., Valencia, CA) and supernatant saliva samples were preserved with SUPE Rase. In™ (Ambion Inc., Austin, TX). The data was entered in the statistical package for social sciences for windows (SPSS) V: 26.RESULTS: A total of 120 samples of oral squamous cell carcinoma were taken, which met theinclusion criteria. Mean age of the patients was 47.45+10.85 years. 85(70.8%) were married and35 (29.2%) were unmarried. 90.0% were married and 5.0% were unmarried, while 5.0% werewidow. Cigarette smoking, paan, chaalia and naswar were the commonest cause of the oralsquamous cell carcinoma. Lips, buccal mucosa and tong were the commonest t sites of the oralsquamous cell carcinoma. 16.7% cases had positive family history of oral squamous cellcarcinoma. Out of all study subjects, most of the cases 59.2% had moderately differentiatedSCC, 30.0% cases had well-differentiated SCC and 10.8% of the cases had poor differentiatedSCC. Out of all study subjects, 87.5% of the patients had positive micro-RNA expression.Micro-RNA expression was significantly associated, with poorly differentiated squamous cellcarcinoma (p=0.016). CONCLUSION: Study revealed that the salivary miroRNA expression were significantlypositive in patients of OSCC. Therefore, salivary microRNA could be considered as a useful andadvantageous biomarker for the detection and tracking of OSCC across various levels of tissueabnormalities