Downregulation of salivary miR-3928 as a potential biomarker in patients with oral squamous cell carcinoma and oral lichen planus

Objectives: Recent studies highlighted the role of miR expressed in saliva as reliable diagnostic and prognostic tools in the long-term monitoring of cancer processes such as oral squamous carcinoma (OSCC). Based on a few previous studies, it seems the miR-3928 can be considered a master regulator in carcinogenesis, and it can be therapeutically exploited. This is the first study that compared oral potentially malignant disorder (OLP) and malignant (OSCC) lesions for miR-3928 expression. Materials and Methods: In this cross-sectional study, saliva samples from 30 healthy control individuals, 30 patients with erosive/atrophic oral lichen planus, and 31 patients with OSCC were collected. The evaluation of miR-3928 expression by q-PCR and its correlation with clinicopathological indices were analyzed by Shapiro-Wilk, Kruskal-Wallis, Pearson's chi(2), and Mann-Whitney tests. The p-value less than .05 indicated statistically significant results. Results: Based on nonparametric Kruskal-Wallis test results, there was a statistically significant difference between the ages of three study groups (p < .05). This test demonstrated a statistically significant difference between the average of miR-3928 expression in three study groups (p < .05). The result of the chi 2 test showed a statistically significant difference in miR-3928 expression between patients with OLP (p = .01) and also patients with OSCC (p < .0001) in comparison to the control group. Conclusions: The salivary miR-3928 can play a tumor suppressive role in the pathobiology of OSCC, and it is significantly downregulated in patients. According to the potential tumor suppressive role of miR-3928 in the OSCC process, we can consider this microRNA as a biomarker for future early diagnosis, screening, and potential target therapy.