Clinicopathological correlation of microRNA 21 expression in oral cancer patients with tobacco chewing habits

Introduction: Oral cancer is one of the most common malignancies and has a significant association with tobacco chewing. Micro RNA 21 (mi-RNA 21) has been identified as oncogenic RNA, implicated in etio-pathogenesis of various neoplastic lesions. Objective: (i) To assess the microRNA 21 expression in oral cancer patients with history of tobacco chewing habits and (ii) to carry out its clinicopathological correlation. Material and Method: The present study was carried out as a case-control study, for a two year period in which a total of 20 biopsy tissue specimen obtained from oral cancer patients having tobacco chewing habits were enrolled as cases and an equal number of biopsy tissue specimen obtained from age, and sex-matched patients of oral leukoplakia were enrolled as controls. Clinical details, personal habits were noted and histopathological assessment was done. miRNA21 was done using Taq Man microRNA assay (ABI) using Polymerase Chain Reaction (PCR).Real time PCR results was analyzed and expressed as relative miRNA expression of the threshold cycle (CT) values. Mean values were compared using independent samples ‘t’-test and ANOVA using SPSS 21.0 software. p-value less than 0.05 indicated a statistically significant association. Results: Mean age of cases was 52.65±7.82 years, majority of cases were males (85%). Among cases, majority (70%) had clinical stage I and were histo-pathologically well differentiated (75%). There were 3 (15%) cases with metastasis. Mean relative miRNA 21 expression were significantly higher in cases (10.53±3.52) as compared to that in controls (8.76±1.16) (p=0.029). Relative miRNA21 values showed a significant increasing trend with increasing clinical stage, histopathological grade and metastasis. Conclusion: miRNA21 expression was able to differentiate between leukoplakia and oral cancer cases. miRNA21 also showed a significant correlation with clinicopathological factors.