Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C1658953 (tumor vasculature)
 2,390 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ten myxoid liposarcomas (ML) were studied ultrastructurally in an attempt to determine the histogenesis of this neoplasm and structural associations which might contribute to their relatively benign clinical behavior. The findings were compared with normal and neoplastic adipose tissue. Three cell types were observed, i.e., "primitive" mesenchymal cells, intermediate cell types, and lipoblasts at various stages of development. The principle differences between the lipoblastic elements were the number and the size of intracytoplasmic fat vacuoles, the development of basement membrane-like material, micropinocytotic vesicles along the plasma membrane and the quantity and pleomorphism of mitochondria. The tumor vasculature was complex but consistently demonstrated a multilayered basal lamina. This finding has been described in neoplasms associated with a relatively good prognosis. This study demonstrates that the better differentiated lipoblasts in ML share some features with normal brown fetal fat and hibernoma. It is, thus, suggested that ML may be derived from brown adipose tissue.
 ...
PMID:Myxoid liposarcoma. An electronmicroscopic study: biological and histogenetic considerations. 15 52

Of 190 sets selective celiac and/or hepatic angiograms obtained in patients with hepatocellular carcinoma (HCC), comparison with gross anatomy of the liver was subsequently made by autopsy in 77 and by surgery in 23. It was found that the gross anatomy of HCC can be assessed with certain accuracy by careful interpretation of the angiograms, because tumor vasculature and vascular alterations in the noncancerous parenchyma are closely related to the mode of tumor growth, size of tumor nodules and their distribution. Even a fibrous capsule of the tumor may be discerned as a radiolucent zone around the tumor contour. Diagnosis of the gross anatomical type of HCC is important to the selection of therapeutic measure and assessment of prognosis.
 ...
PMID:Angiographic assessment of gross anatomy of hepatocellular cardinoma: comparison of celiac angiograms and liver pathology in 100 cases. 19 72

Postirradiation reoxygenation kinetics of the Walker 256 carcinoma were examined and related to radiation-induced changes in tumor vascular functions. Changes in the hypoxic cell component of irradiated Walker tumors may occur by two mechanisms. Reoxygenation of previously hypoxic cells may be due to an increased rate of blood flow in some parts of the tumor. Hypoxic tumor cells may also be eliminated by cell death due to prolonged or severe hypoxia in other parts of the tumor as a result of substantial damage to the tumor vasculature as seen in radiation-induced changes in vascular volume and blood vessel permeability. Reoxygenation of experimental tumors following single, massive doses of radiation may be different from that occurring in human tumors during the course of multifraction radiotherapy.
 ...
PMID:Tumor reoxygenation and postirradiation vascular changes. 66 81

A postmenopausal patient presented with a pelvic mass and ascites. The CA-125 level was 329 U/ml, and transvaginal color Doppler sonography of the tumor vasculature suggested malignancy. At laparotomy, a luteinized thecoma and cytologically benign ascites were found. On rare occasions ovarian thecoma may be associated with ascites without hydrothorax. Preoperative evaluation of the patient with ascites and a pelvic mass may suggest malignancy, but histologic confirmation is necessary to exclude this rare association.
 ...
PMID:Transvaginal color Doppler sonography and CA-125 elevation in a patient with ovarian thecoma and ascites. 132 79

The concept of antiangiogenic therapy was first proposed in the early 1970s as a method of restricting tumor growth by inhibiting angiogenesis. In subsequent years sufficient knowledge about the process of angiogenesis itself was obtained so that it is now possible to begin to develop antiangiogenic therapy for clinical use. At least three strategies are feasible: (i) inhibition of release of angiogenic molecules from tumor cells; (ii) neutralization of angiogenic molecules that have already been released; and (iii) inhibition of vascular endothelial cells from responding to angiogenic stimulation. Most of the angiogenic inhibitors that have been discovered at the time of writing, directly interfere with the ability of endothelial cells to form new capillary blood vessels. Antiangiogenic activity is a newly found property of alpha-interferon. Although alpha-interferon is a relatively weak angiogenesis inhibitor in comparison to others, it has been very successful in the treatment of life-threatening hemangiomas in children. Early clinical experience with this first angiogenesis inhibitor to reach clinical trial, indicates that optimal antiangiogenic therapy in the future is likely to be based on the long-term use of inhibitors with low toxicity, and with little chance of inducing drug-resistance. It is apparent that different types of angiogenesis inhibitor may be administered together and that these compounds may also be administered to cancer patients as adjuncts to conventional chemotherapy. It is important to recognize that tumor vasculature has other properties besides angiogenesis, which make it a potential specific target for anti-cancer therapy.
 ...
PMID:Inhibition of angiogenesis. 137 14

Photodynamic therapy (PDT) is an experimental form of cancer therapy which employs photoactivation of a sensitizing chemical by light of a given wavelength via the production of toxic oxygen species. PDT causes local destruction of cancer, and relies on a therapeutic index between normal and malignant tissue since the latter seems to selectively retain the sensitizer. PDT has both direct tumoricidal effects as well as indirect effects on tumor vasculature causing an early hemorrhagic necrosis of tissue. The treatment has been used for the treatment of endobronchial obstruction by primary and metastatic tumors. Most recently, trials are being performed to evaluate this therapy as a surgical adjunct in the treatment of pleural malignancies such as mesothelioma.
 ...
PMID:Photodynamic therapy for thoracic malignancies. 138 70

An attractive approach to the therapy of solid tumors would be to target cytotoxic agents or coagulants to the vasculature of the tumor rather than to the tumor cells themselves. This strategy has 3 advantages: (a) it should be applicable to many types of solid tumors because all require a blood supply for survival and growth; (b) the target endothelial cells are directly accessible through the blood and are normal cells, making the outgrowth of resistant mutants unlikely; and (c) there is an in-built amplification mechanism because thousands of tumor cells are reliant on each capillary for nutrients and oxygen. Despite its theoretical attractions, the approach of tumor vascular targeting has not been testable because antibodies that recognize tumor vascular endothelial cell antigens with adequate specificity are currently not available. In this study, we developed a model system in which to investigate the antibody-directed targeting of vascular endothelial cells in solid tumors in mice. A neuroblastoma transfected with the mouse interferon-gamma gene, C1300(Mu gamma), was grown in antibiotic-treated BALB/c nude mice. The interferon-gamma secreted by the tumor induces the expression of major histocompatibility complex Class II antigens on the tumor vascular endothelium. Class II antigens are absent from the vasculature of normal tissues, although they are present on B-lymphocytes, cells of monocyte/macrophage lineage, and some epithelial cells. Anti-Class II antibody administered i.v. strongly stains the tumor vasculature, whereas an antitumor antibody directed against a major histocompatibility complex Class I antigen of the tumor allograft produces classical perivascular tumor cell staining. This model should enable the theoretical superiority of tumor vascular targeting over conventional tumor cell targeting to be tested.
 ...
PMID:A murine model for antibody-directed targeting of vascular endothelial cells in solid tumors. 139 21

Cell surface antigens of transformed cells are the traditional targets for antibody-guided detection and therapy of solid neoplasms. Alternative targets may be found in the tumor stroma, which contains newly formed blood vessels, reactive fibroblasts, and extracellular matrix proteins. The F19 cell surface glycoprotein of reactive fibroblasts is a prototypic stromal antigen since it is found in the stroma of > 90% of common epithelial cancers but is absent or expressed at low levels in normal tissues and benign epithelial tumors. In the present study, we define an additional tumor stromal antigen, FB5, that is selectively expressed in vascular endothelial cells of malignant tumors. Immunohistochemical analysis of 128 tumors identified FB5 in endothelial cells in 67% of the samples (including 41 of 61 sarcomas, 26 of 37 carcinomas, and 18 of 25 neuroectodermal tumors) whereas normal blood vessels and other adult tissues tested lacked FB5 expression. In vitro studies showed that FB5 is a M(r) 165,000 cell surface glycoprotein, comprised of a M(r) 95,000 core polypeptide and highly sialyated O-linked oligosaccharides but few if any N-linked sugars, and that the FB5 gene is located on chromosome 11q13-qter. The restricted tissue distribution of the FB5 protein, which we refer to as endosialin, suggests strategies for tumor imaging and therapy that are aimed primarily at the tumor vasculature.
 ...
PMID:Identification of endosialin, a cell surface glycoprotein of vascular endothelial cells in human cancer. 143 85

In December 1991, the National Cancer Institute held a workshop to evaluate the role of magnetic resonance (MR) spectroscopy in human cancer biology. The clinical and basic cancer research issues requiring use of MR spectroscopy, the advantages and limitations of MR spectroscopy, and future directions in MR spectroscopy of cancer were discussed. Consensus-building panels were formed on the following four topics: cell membrane biochemistry, tumor therapeutic response or drug resistance, appropriate model systems, and potential clinical applications of MR spectroscopy. The workshop members concluded that large prospective clinical studies as well as in vivo animal and human studies to define prognostic variables should be performed, with correlation between MR spectroscopic results and biochemical and physiologic features. Studies of phospholipid metabolism, the pharmacokinetics of anticancer agents, and effects of new cancer treatments on the tumor vasculature and normal tissues are needed.
 ...
PMID:Proceedings of a National Cancer Institute workshop: MR spectroscopy and tumor cell biology. 143 79

A noninvasive dynamic method for the measurement of blood flow, using 15O-labeled water and positron emission tomography, has been developed and used to study 20 patients with breast carcinoma. The mean tumor flow was 29.8 +/- 17.0 (SE) ml/dl/min of tissue, while normal breast flow was 5.6 +/- 1.4 ml/dl/min of tissue. The exchanging water space of tissue known as the volume of distribution of the tracer (Vd) was also derived. This is defined as the volume of water in tissue that exchanges with a unit volume of water in arterial blood during the period of the study (7 min). The mean tumor Vd was 0.56 +/- 0.15 ml/ml while normal breast Vd was 0.14 +/- 0.05 ml/ml. The low value in normal breast is partly due to the high fat content of the tissue. The mean flow per unit of exchangeable volume was similar in tumor (52.8 +/- 22.0) and normal breast tissue (45.2 +/- 20.0). This suggests that the major discrepancy seen in measured values of flow between breast tumors and normal breast principally reflects the different composition of the two tissues. This method is rapid and suited for studying the reactivity of human tumor vasculature, so extending studies are being performed on animal tumors.
 ...
PMID:Measurements of blood flow and exchanging water space in breast tumors using positron emission tomography: a rapid and noninvasive dynamic method. 154 Sep 69


1 2 3 4 5 6 7 8 9 10 Next >>