Validation of salivary microRNA 301a as a potential non-invasive diagnostic biomarker in gastric carcinoma.

[CONTEXT] Early detection of cancer is key to good prognosis and improved survival rate. Gastric cancer (GC) is fatal and presents with poor prognosis as it is usually diagnosed only at advanced stages. Saliva is emerging as a preferred diagnostic tool due to its advantages of being non-invasive, easy to collect, and cost-effective. Salivary microRNAs (miRNA) are more reliable due to their stability, resistance to degradation and its abundant involvement in cancer progression.

[AIM] To estimate and validate the potential of salivary miRNA 301a in the diagnosis of Gastric cancer.

[METHODS AND MATERIALS] This Cross-sectional study comprised of 60 GC patients (Group I) and 60 normal controls (Group II). Fold change (FC) values of serum and salivary miRNA301a levels were estimated using the Real Time-Polymerisation Chain Reaction (RT-PCR) and compared between the study groups. Correlation between the serum and salivary miRNA301a levels was also evaluated. MiRNA301a levels were compared and correlated, with the clinical stage and histopathological grades of GC.

[RESULTS] The mean FC of serum (Mean ± SD = 2.62 ± 0.75, Mean Rank = 90.5) and salivary (Mean ± SD = 2.03 ± 0.56, Mean Rank = 90.5) miRNA301a was significantly higher in Gastric cancer patients compared to controls (Mean ± SD = 0.99 ± 0.004, Mean Rank = 30.5). Salivary miRNA301a levels exhibited significant positive correlation with serum miRNA301a in gastric cancer patients (r = 0.941). The mean FC of serum and salivary microRNA 301a exhibited significant correlation with the clinical stages and histopathological grades of GC.

[CONCLUSION] Salivary miRNA301a is a potential reliable diagnostic tool for early screening of Gastric cancer.