Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0598934 (tumor growth)
 58,965 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

70 BD-IX rats, in which chemically induced mixed gliomas have been transplanted intracerebrally, were investigated by microangiography. The pattern and the degree of tumor vascularisation of all animals was correlated with the histological findings. Depended on the type of the tumor different localisations of tumor growth could be found: G XII-gliomas preferred the juxtaventricular region and subarachnoid space whereas GL 2.2-gliomas mainly grew as solid intracerebral space occupying lesions. Microangiograms of all tumor stages from the 14th to 42nd day after transplantation revealed a typical vascular pattern consisting of lacunar, glomerulose and netlike vessels. Further, necrosis, bleedings into the tumor, and irregularities of the capillary network could be demonstrated. The volume, age and vascularisation of the tumors are correlated and the results are discussed with regard to the principles of tumor growth and malignancy.
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PMID:[Neuroradiology of the normal and pathological anatomy of the rat brain. II Microangiographic investigations of the vascularisation of transplanted malignant brain tumors (author's transl)]. 645 95

Human low-grade gliomas represent a population of brain tumors that remain a therapeutic challenge. Preclinical evaluation of agents, to test their preventive or therapeutic efficacy in these tumors, requires the use of animal models. Spontaneous gliomas develop in models of chemically induced carcinogenesis, such as in the transplacental N-ethyl-N-nitrosourea (ENU) rat model. However, without the ability to detect initial tumor formation, multiplicity or to measure growth rates, it is difficult to test compounds for their interventional or preventional capabilities. In this study Fisher-334 rats, treated transplacentally with ENU, underwent magnetic resonance imaging (MRI) examination in order to evaluate this approach for detection of tumor formation and growth. ENU-induced intracranial cerebral tumors were first observable in T2-weighted images beginning at 4 months of age and grew with a mean doubling time of 0.487 +/- 0.112 months. These tumors were found histologically to be predominately mixed gliomas. Two therapeutic interventions were evaluated using MRI, vitamin A (all-trans retinol palmitate, RP), as a chemopreventative agent and the anti-angiogenic drug SU-5416. RP was found to significantly delay the time to first tumor observation by one month (P = 0.05). No differences in rates of tumor formation or growth rates were observed between control and RP-treated groups. MRI studies of rats treated with SU-5416 resulted in reduction in tumor growth rates compared to matched controls. These results show that MRI can be used to provide novel information relating to the therapeutic efficacy of agents against the ENU-induced tumor model.
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PMID:Magnetic resonance imaging of ethyl-nitrosourea-induced rat gliomas: a model for experimental therapeutics of low-grade gliomas. 1171 57

Serial magnetic resonance images of 27 patients with untreated World Health Organization grade II oligodendrogliomas or mixed gliomas were reviewed retrospectively to study the kinetics of tumor growth before anaplastic transformation. Analysis of the mean tumor diameters over time showed constant growth. Linear regression, using a mixed model, found an average slope of 4.1mm per year (95% confidence interval, 3.8-4.4mm/year). Untreated low-grade oligodendrogliomas or mixed gliomas grow continuously during their premalignant phase, and their pattern of growth can be predicted within a relatively narrow range. These findings could be of interest to optimize patients management and follow-up.
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PMID:Continuous growth of mean tumor diameter in a subset of grade II gliomas. 1266 21