Publications by authors named "Sevdalin Natchev"

Aims: The chemokine receptor CXCR7 is found on glioma cells and glioma-associated vessels and dependent upon its localisation on tumour or endothelial cells the CXCR7 receptor can mediate glioma cell invasion and tumour angiogenesis. Its expression predicts survival in several types of cancers.

Methods: We immunohistochemically studied the expression of CXCR7 and its ligand SDF1α in a cohort of 354 human patients with glioma.

View Article and Find Full Text PDF

Background: Recently, isocitrate dehydrogenase 1 (IDH1) was identified as a major participant in glioma pathogenesis. At present, the enzymatic activity of the protein has been the main topic in investigating its physiological function, but its signaling pathway allocation was unsuccessful. Interestingly, proteins regulated by phosphoinositide 3-kinase (PI3K)/Akt signaling, are among the top downregulated genes in gliomas associated with high percentage of IDH1 and IDH2 mutations.

View Article and Find Full Text PDF

Gliomas are the most common primary brain tumours. Several independent studies have shown that isocitrate dehydrogenase 1 (IDH1) mutation in diffuse gliomas is associated with a more favourable patient outcome. The aim of this study was to evaluate the prognostic relevance of an antibody specifically detecting the R132H point mutation of IDH1 in tissue sections in a large series of human gliomas.

View Article and Find Full Text PDF

Background: Animal studies have shown cooperative contribution of the Ras/Raf/MAPK and PI3K/Akt/mTOR signaling pathways in glioblastoma formation. However, this joint action has not yet been confirmed in human studies.

Methods: The expression of Raf kinase inhibitory protein (RKIP) was examined in 159 patients with high-grade and low-grade gliomas and correlated with previously obtained data on the activation of signal transducer and activator of transcription 3 (STAT3), a downstream effector of the PI3K/Akt/mTOR signaling pathway.

View Article and Find Full Text PDF

Signal transducer and activator of transcription protein 3 (STAT3) is a regulator of central nervous system (CNS) development and a promising therapeutic target in human cancers. Activation of STAT3 promotes oncogenesis in a variety of tissues, but knowledge of its role in glioblastoma is still limited. Recent results indicate that STAT3 acts as a tumor suppressor or an oncogene depending upon the genetic background of the tumor.

View Article and Find Full Text PDF