Investigation of mirnas in the peripheral circulation of patients with uveal malignant melanoma

Uveal malignant melanoma is a type of intraocular malignancy in adults, that seriously affects eyesight and quality of life. As a poor prognosis tumor in the early stages, shortens the survival time. Therefore, it seems that there is a need for new markers for both the development of treatment protocols and for early diagnosis. In addition, genetic and epigenetic researches related to uveal malignant melanoma are extremely limited. MicroRNAs are a member of non-protein-coding RNAs, containing approximately 22 nucleotides, regulate the suppression of gene expression and post-transcriptional activity of target mRNAs. Therefore, it plays an important role in cancer development. It contributes to malignant transformation of cells by affecting proliferation, differentiation and apoptosis. In the presented study, expression of miR-181b, miR-155, miR-454 occurred in serum samples of 72 uveal melanoma patients cohort and 72 healthy controls. For gene expression analysis, RNA isolation from peripheral blood, cDNA synthesis specific to miRNAs followed by Real-Time PCR methods were performed. As a result of the study, it was seen that miRNA gene expression levels increased more than twice in the patient groups compared to healthy controls and it was statistically significant (p<0,05). The p values obtained for each miRNA; p miR-181b, p< 0,001; miR-155, p< 0,001 miR-454, p=0,005. In addition, when miRNA expression levels were compared with the clinical data of the patients; There was a significant relationship between miR-155 and radiation treatment option (P value= 0,040), and relationship between miR-454 and smoking (p value=0,009 ) and alchol intake (p value= 0,026) of patients. The findings suggest that the miRNAs examined have an oncogenic character in cancer patients and thus, trigger primer and metastatic uveal malignant melanoma. The miR-181b, miR-155 and miR-454 molecules are thought to be highly potential biomarkers for detecting uveal melanoma and demonstrating prognosis. Key Words: Uveal malignant melanoma, miR-181b, miR-155, miR-454, Biomarker. The present work was supported by the Research Fund of Istanbul University. Project No. TDK-2019-35336.