LAUSR

e13008 Background: The new 2016 WHO classification of tumors of the central nervous system takes into consideration mutational status of IDH genes. Research of molecular changes in gliomas remain to be an actual issue. We analyzed the gene expression of some significant pathways in gliomas. Methods: 27 patients (12 females, 15 males) aged from 27 to 76 years with verified brain tumors (glioblastomas (G4) – 67%, anaplastic astrocytomas and oligoastrocytomas (G3) – 11%, astrocytomas (G2) – 22%) were investigated. 7 mutations in the IDH1 gene and 5 ones in IDH2 in fresh frozen tumor tissues were detected by RT-qPCR with Therascreen IDH1/2 RGQPCR kit (Qiagen). The expressions of EGFR, SMAD4, SMAD7, SMO, NOTCH1, NOTCH2, HBP1, HIF1A, EGLN1, EGLIN3, KDM1B, KDM1A, MSI1, MSI2, TET1 genes in tumor and normal brain tissue obtained while surgical access were assessed with RT-qPCR. PSMC, TBP and RPLO were used as reference genes. Results: Analysis of IDH1/2 status revealed only R132H mutation of IDH1 in 6 patients. The ratio of the relative expression of genes in tumor tissue with mutation and wild-type and the significance of the differences in the Mann-Whitney test are presented in the table below . Conclusions: Expression of SMAD7, EGLN1, EGLN3 as an activating factor of TGF-b-signaling pathway potentially may be used as an additional prognostic marker of gliomas progression.[Table: see text]