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Introduction: The most common and aggressive primary malignancy of the central nervous system is Glioblastoma that, as a wide range of malignant solid tumor, is characterized by extensive hypoxic regions. A great number of PET
mTOR/S6K pathway is a crucial regulator of cell growth and metabolism. Deregulated signalling via S6K has been linked to various human pathologies, including metabolic disorders and cancer. Many of the molecules signalling upstream of S6K have been shown to be either mutated or overexpressed in
The pathogenesis of many tumors, including brain tumors, has been associated with hypoxia, which induces the transcriptional activity of hypoxia-inducible Factor-1α (HIF-1α). HIF-1α is normally degradated by the von Hippel-Lindau protein (pVHL) but, in hypoxia, pVHL/HIF-1α interaction is inhibited
We consider emergent collective behavior of a multicellular biological system. Specifically, we investigate the role of hypoxia (lack of oxygen) in migration of brain tumor cells. We performed two series of cell migration experiments. In the first set of experiments, cell migration away from a tumor
Oxygen is a fundamental element for all living organisms, and modifications in its concentration influence several physiological and pathological events such as embryogenesis, development and also aging. Regulation of oxygen levels is an important factor in neural stem cell biology (e.g.
OBJECTIVE
Primary brain tumors are common type of neoplasms. The most common are astrocytic tumors, so do meningiomas of various grades. The etiology is still unknown; however, there are lots of data presenting new theories about genetic alterations responsible for low- or high-grade astrocytic
Tissue hypoxia results from the interaction of cellular respiration, vascular oxygen carrying capacity, and vessel distribution. We studied the relationship between tumor vasculature and regions of low pO(2) using quantitative analysis of binding of the 2-nitroimidazole EF5 given to patients
The presence of radioresistant hypoxic cells in human brain tumors limits the overall effectiveness of conventional fractionated radiation therapy. Tumor-specific therapies that target hypoxic cells are clearly needed. We have investigated the expression of suicide genes under hypoxia by a
The resistance of gliomas to treatment with radiation and antineoplastic drugs may result in part from the effects of the extensive, severe hypoxia that is present in these tumors. It is clear that brain tumors contain extensive regions in which the tumor cells are subjected to unphysiological
Hypoxia is associated with resistance to radiotherapy and chemotherapy in malignant gliomas, and it can be imaged by positron emission tomography with 18F-fluoromisonidazole (18F-FMISO). Previous results for patients with brain cancer imaged with 18F-FMISO at a
Malignant brain tumors exhibit distinct metabolic characteristics. Despite high levels of lactate, the intracellular pH of brain tumors is more alkaline than normal brain. Additionally, with increasing malignancy, brain tumors display intratumoral hypoxia. Carbonic anhydrase (CA) IX and XII are
Adult human adipose-derived mesenchymal stem cells (hAMSCs) are multipotent cells, which are abundant, easily collected, and bypass the ethical concerns that plague embryonic stem cells. Their utility and accessibility have led to the rapid development of clinical investigations to explore their
PURPOSE
The aim of this study was to generate a multivariate model using various MRI markers of blood flow and vascular permeability and accumulation of
18F-fluorodeoxyglucose (FDG) to predict the extent of
hypoxia in an
18F-fluoromisonidazole
OBJECTIVE
The aim of this study was to clarify the relationship between tumor hypoxia and microscopic diffusion capacity in primary brain tumors using (62)Cu-Diacetyl-Bis (N4-Methylthiosemicarbazone) ((62)Cu-ATSM) PET/CT and diffusion-weighted MR imaging (DWI).
METHODS
This study was approved by the
The membrane-anchored metalloproteinase tumor necrosis factor-alpha-converting enzyme (TACE/a disintegrin and metalloproteinase [ADAM] 17) is key in proteolytic ectodomain shedding of several membrane-bound growth factors, cytokines and receptors. The expression and activity of ADAM17 increases