Mehmet ALPTEKİN, Necati UCLER, Ibrahim ERKUTLU, Murat GEYİK, Mert NAZİK, Ali ATADAG, Ali NEHİR

Comparison of serum and tissue values of miRNAs related to autophagy in glial brain tumors and metastases other than lmphoma

Aim: Central nervous system tumors are seen in both children and adults, and most of these tumors cause disability and death. Current studies are focused on the molecular pathogenesis to identify new targets for the diagnosis and follow-up of patients. In this study, we investigated whether serum micro ribonucleic acid (miRNA) values could be used as biomarkers of these tumors by examining miRNA levels associated with autophagy in serum and tissue.Material and Methods: We included 27 patients who underwent surgery at our clinic and were diagnosed with glial tumor or metastasis other than lymphoma after pathological examination. The serum and tissue levels of miRNAs associated with autophagy were compared, and correlations between the obtained values were determined using Student’s t-test.Results: Based on histopathological examination, there were 14 glioblastomas, 3 oligodendrogliomas, 2 anaplastic astrocytomas, 2 carcinoma metastases, 2 pilocytic astrocytomas, 1 anaplastic ependymoma, 1 anaplastic oligodendroglioma, 1 diffuse astrocytoma, and 1 ependymoma. Serum Ct values were significantly higher than tissue Ct values. Correlations were found between serum and tissue levels of 5 miRNA subtypes. In addition, we could not determine the Ct value in some serum samples for 5 of the 12 miRNA subtypes.Conclusion: Although correlations were found between serum and tissue miRNA levels in the literature, we did not find any reasonable correlation, which might be explained by the less number of patients in our study. Therefore, considering the results of this study, we believe it is too early to determine that miRNAs cannot be biomarkers of brain tumors.

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