Compare serum and tissue miRNA level associated with autophagy in the patient who has glial tumor or metastatic tumor except lymphoma

Introduction: Central nervous system tumors occur in both pediatric and adult patients and many of these tumors cause morbidity and mortality. In an effort to identify new targets for diagnosis and follow up the patients, recent studies have focused on molecular area. In this study, It was aimed to investigate whether serum miRNA levels can be used as a biomarker, especially by looking at tissue and serum levels of miRNA associated with autophagy. Method: In this study, we include 27 patients who were operated in our clinic, whose pathology specimen reported as a glial tumor or metastatic tumors. We compared serum and tissue levels of miRNAs which are especially associated with autophagy and checked the correlation between these values by using student t-test. Results: In the histopathological examination; 14 glioblastomas, 3 olidendrogliomas, 2 anaplastic astrocytomas, 2 metastatic tumors, 2 pilocytic astrocytomas, 1 anaplastic ependymoma, 1 anaplastic oligodendroglioma, 1 diffuse astrocytoma and 1 ependymoma were observed. In all ceses serum Ct levels are statistically higher than tissue Ct levels (p<0,001). On the other hand we found the correlation between serum and tissue levels only for five miRNA subtypes. In addition we could not detect ant Ct in 5 of 12 miRNA subtypes in the some serum samples. Conclusion: Although there is correlation between levels of serum miRNA levels in the tumor tissue in the literature, we did not find any plausible correlation in this study. The low number of patients in our study may explain the inconsistency with this literature. So, looking at the results of this study, we believe that it is early to say that miRNA can not be a biomarker for brain tumors. Keywords: Glial tumors, miRNA, autophagy, biomarker