PROX1 is a transcription factor with an essential role in embryonic development and determination of cell fate. In addition, PROX1 has been ascribed suppressive as well as oncogenic roles in several human cancers, including brain tumors. In this study we explored the correlation between PROX1 expression and patient survival in high-grade astrocytomas.
View Article and Find Full Text PDFGlioblastoma (grade IV glioma) is the most common and aggressive adult brain tumor. A better understanding of the biology of glioblastoma cells is crucial to identify molecular targets stimulating cell death. NPM1 (nucleophosmin) is a multifunctional chaperone that plays an important role in cancer development.
View Article and Find Full Text PDFBackground: The survival of high-grade glioma patients is poor and the treatment of these patients can cause severe side effects. This fosters the necessity to identify prognostic biomarkers, in order to optimize treatment and diminish unnecessary suffering of patients. The aim of this study was to identify prognostic biomarkers for high-grade glioma patients.
View Article and Find Full Text PDFRecent studies suggest that the regulatory networks controlling the functions of stem cells during development may be abnormally active in human cancers. An embryonic stem cell (ESC) gene signature was found to correlate with a more undifferentiated phenotype of several human cancer types including gliomas, and associated with poor prognosis in breast cancer. In the present study, we used tissue microarrays of 80 low-grade (WHO Grade II) and 98 high-grade human gliomas (WHO Grades III and IV) to investigate the presence of the ESC-related proteins Nanog, Klf4, Oct4, Sox2 and c-Myc by immunohistochemistry.
View Article and Find Full Text PDFThe homeobox gene PROX1 is critical for organ development during embryogenesis. The Drosophila homologue, known as prospero has been shown to act as a tumor suppressor by controlling asymmetric cell division of neuroblasts. Likewise, alterations in PROX1 expression and function are associated with a number of human cancers including hematological malignancies, carcinomas of the pancreas, liver and the biliary system, sporadic breast cancer, Kaposiform hemangioendothelioma, colon cancer, and brain tumors.
View Article and Find Full Text PDFGABA (γ-aminobutyric acid) is the main inhibitory neurotransmitter in the CNS and is present in high concentrations in presynaptic terminals of neuronal cells. More recently, GABA has been ascribed a more widespread role in the control of cell proliferation during development where low concentrations of extrasynaptic GABA induce a tonic activation of GABA receptors. The GABA-A receptor consists of a ligand-gated chloride channel, formed by five subunits that are selected from 19 different subunit isoforms.
View Article and Find Full Text PDFJ Neuropathol Exp Neurol
February 2010
PROX1 is a prospero-related transcription factor that plays a critical role in the development of various organs including the mammalian lymphatic and central nervous systems; it controls cell proliferation and differentiation through different transcription pathwaysand has both oncogenic and tumor-suppressive functions. We investigated PROX1 expression patterns in 56 human astrocytic gliomas of different grades using immunohistochemistry. An average of 79% of cells in World Health Organization Grade IV (glioblastoma, n = 15) and 57% of cells in World Health Organization Grade III (anaplastic astrocytoma, n = 13) were strongly PROX1 positive; low-grade diffuse astrocytomas (Grade II, n = 13) had 21% of cells that were strongly positive; Grade I tumors (n = 15) had 1.
View Article and Find Full Text PDFTranscriptional regulation by p53 is critical for p53-mediated tumour suppression; however, p53-mediated transactivation has been dissociated from p53-mediated biological processes including apoptosis, DNA repair, and differentiation. We compared the effects of a mutant allele, p53(QS - val135), containing a double mutation in the amino-terminus abrogating transactivation activity and a modification at amino acid 135 partially affecting DNA binding, to complete loss of p53. We applied in vitro endpoints correlated with epithelial tumourigenesis and an in vivo assay of tumour phenotype to assess whether loss of p53-mediated transcriptional regulation underlies the malignant phenotype of p53(-/-)/v-ras(Ha)-overexpressing keratinocytes.
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