ependymoma/tyrosine

Malignant gliomas and childhood ependymomas have a high rate of treatment failure. Epidermal growth factor receptor (EGFR) activation has been implicated in the tumorigenesis and radioresistance of many cancers, including brain tumors. Therefore, combining EGFR targeting with irradiation is a

Up to now, several clinical studies have been started investigating the relevance of receptor tyrosine kinase (RTK) inhibitors upon progression free survival in various pediatric brain tumors. However, single targeted kinase inhibition failed, possibly due to tumor resistance mechanisms. The present

We have used the polymerase chain reaction to clone and characterize growth factor receptor tyrosine kinases (RTKs) expressed in 3 pathologically distinct pediatric brain tumors, an anaplastic ependymoma, a glioblastoma multiforme and a primitive neuroectodermal tumor (PNET). These neoplasms are

KIT receptor tyrosine kinase is expressed in tumor endothelial cells of adult glioblastomas, but its expression in pediatric brain tumor endothelial cells is unknown. We assessed expression of KIT, phosphorylated KIT, stem cell factor (SCF) and vascular endothelial growth factor receptor-2 (VEGFR-2)

Here, we review the recent literature on molecular discoveries in ependymomas and pediatric diffuse gliomas. Ependymomas can now be categorized into three location-related subgroups according to their biological profile: posterior fossa ependymomas, group A (PFA) and B (PFB), and supratentorial

C-kit is a proto-oncogene located on the long arm of chromosome 4. Its product, CD117, is a specific immunohistochemical (IHQ) marker that is associated with response to a potent tyrosine kinase inhibitor therapy with STI-571 (Gleevec®) in chronic myelogenous leukemia and GISTs. In our study, we

Vascular endothelial growth factor (VEGF) is a hypoxia-inducible angiogenic factor, which is known to be upregulated in most cases of glioblastoma multiforme (GBM). The expression of VEGF and its receptors in ependymomas, oligodendrogliomas, and particularly the expression during anaplastic

Tumor angiogenesis and receptor tyrosine kinases (RTK) are major novel targets in anticancer molecular therapy. Accordingly, we characterized the vascular network and the expression pattern of angiogenic RTK in the most frequent pediatric brain tumors. In a retrospective collection of 44 cases (14

Pediatric ependymomas are enigmatic tumors, and their clinical management remains one of the more difficult in pediatric oncology. The identification of biological correlates of outcome and therapeutic targets remains a significant challenge in this disease. We therefore analyzed a panel of

Children with ependymoma (EPN) are cured in less than 50% of cases, with little improvement in outcome over the last several decades. Chemotherapy has not affected survival in EPN, due in part to a lack of preclinical models that has precluded comprehensive drug testing. We recently developed two

By qPCR we found that EDG3 and SHC3 were amplified in 60% of ependymomas but none in choroid plexus papillomas. In ependymomas EDG3 and SHC3 amplification increased Shc3 protein levels while EDG3 was less affected. Both proteins were co-immunoprecipitated from ependymoma and Shc3 was tyrosine

OBJECTIVE This study was designed to investigate the biological and therapeutic significance of ERBB1, ERBB2, ERBB3, and ERBB4 in childhood ependymoma. METHODS The expression frequency and clinical significance of ERBB1-4 was analyzed in a large cohort of pediatric ependymoma (n = 121) using

Sunitinib malate is a small multi-targeted tyrosine kinase inhibitor that inhibits vascular endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor (PDGFR) and stem cell factor receptor (KIT), which are highly expressed by some high-grade brain tumors. We conducted a

The basis for molecular and cellular heterogeneity in ependymomas of the central nervous system is not understood. This study suggests a basis for this phenomenon in the selection for mitogen-independent (MI) stem-like cells with impaired proliferation but increased intracranial tumorigenicity. MI

OBJECTIVE Primary central nervous system (CNS) tumors represent a diverse group of tumor types with heterogeneous molecular mechanisms that underlie their formation and maintenance. CNS tumors depend on angiogenesis and often display increased activity of ErbB-associated pathways. Current