Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The urokinase-dependent activation of plasminogen by breast cancer cells plays an important role in metastasis. We have previously shown that the metastatic breast cancer cell line MDA-MB-231 over-expresses urokinase and binds and efficiently activates plasminogen at the cell surface compared to non-metastatic cells. The aim of this study was to further characterise plasminogen binding and determine the topology of cell surface-bound plasminogen in terms of its potential for activation. The lysine-dependent binding of plasminogen at 4 degrees C to MDA-MB-231 cells was stable and resulted in an activation-susceptible conformation of plasminogen. Topologically, a fraction of bound plasminogen was co-localised with urokinase on the surfaces of MDA-MB-231 cells where it could be activated to plasmin. At 37 degrees C plasmin was rapidly lost from the cell surface. Apart from actin, other candidate plasminogen receptors were either not expressed or did not co-localise with plasminogen at the cell surface. Thus, based on co-localisation with urokinase, plasminogen binding is partitioned into two functional pools on the surface of MDA-MB-231 cells. In conclusion, these results shed further light on the functional organisation of the plasminogen activation cascade on the surface of a metastatic cancer cell.
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PMID:The topology of plasminogen binding and activation on the surface of human breast cancer cells. 1155 45

Eukaryotic initiation factor 4E (eIF4E) binds the 5'-cap of eukaryotic mRNAs and overexpression of eIF4E in epithelial cell cancers correlates with the metastases/tissue invasion phenotype. Photolabeling of eIF4E with [gamma-32P]8-azidoguanosine 5'-triphosphate (8-N3GTP) demonstrated cross-linking at Lys-119 in the S4-H2 loop which is distant from the m7GTP binding site [Marcotrigiano et al. (1997) Cell 89, 951-961; Friedland et al. (1997) Protein Sci. 6, 125-131]. Modeling studies indicate that 8-N3GTP cross-linked with Lys-119 because it binds a site that is occupied by the second nucleotide of a bound mRNA. Mutagenesis of the S4-H2 loop produced proteins with a 5-10-fold higher affinity for m7GTP than wild-type eIF4E. These mutants of eIF4E may have uses in selectively purifying mRNAs with intact 5'-ends or in determining how the promyelocytic leukemia protein decreases the affinity of eIF4E for mRNA caps.
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PMID:Mutations in the S4-H2 loop of eIF4E which increase the affinity for m7GTP. 1195 93

Isopeptides (ϵ-peptides) of lysine, with a given Mw and low polydispersity (10-400 units), were synthesized to study the relationship between their chemical structure and biological effect. The designed compounds were of high purity, low polydispersity and high stereochemical purity. The effect of the compounds was tested on a human erythroleukemia cell line (K-562) and on four transplantable mouse tumors (L1210 lymphoid leukemia, P38 macrophage derived tumor, Ehrlich ascites carcinoma, Lewis lung tumor /LLT/). In case of the L1210 and P388 tumors and the Ehrlich carcinoma, survival of the animals was used as an indicator of the effect. In case of the Lewis lung tumor, the number and size of metastases in the lung and/or liver of treated and untreated mice were used as indicators. The polymers of polymerisation degree 80-120 (Mw 10.2-15.4 KD) showed the strongest antiproliferative effect both on K562 cells and the tumors growing in vivo. This effect was manifest with a significantly higher survival rate as compared to the control (L1210, P38, Ehrlich ascites), furthermore, by a decrease in the number and size of liver and lung metastases (LLT).
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PMID:Antitumor effect of lysine-isopeptides. 1207 54

Despite improvements in treatment of patients with head and neck squamous cell carcinoma (HNSCC) over the last two decades, the survival rate of these patients has not increased significantly. One of the major factors in the poor outcome of the disease is regional metastasis. To better understand the mechanisms of this process at the protein level, we performed two-dimensional electrophoresis (2-DE) and mass spectrometry using SELDI ProteinChip technology to identify proteins differentially expressed in two HNSCC cell lines, UMSCC10A and UMSCC10B, from the same patient. UMSCC10A was derived from the primary tumor and UMSCC10B from a metastatic lymph node. The differentially expressed proteins were excised from the gels. Following in-gel digestion by trypsin, mass profiles of the peptides were generated. Proteins were identified by submitting the peptide mass profiles to a public available NCBInr databases (www.proteometrics.com). Two membrane-associated proteins, annexin I and annexin II and glycolytic protein enolase-alpha were found to be upregulated, and calumenin precursor down-regulated, in metastatic cell line UMSCC10B. The identity of these proteins was confirmed by analyzing additional peptide mass fingerprints obtained by endoproteinase lysine-C digestion. The results were also validated by Western blotting analysis. Our results showed that enolase-alpha, annexin-I and annexin-II might be important molecules in head and neck cancer invasion and metastasis. The results also suggest an important complementary role for proteomics in identification of molecular abnormalities important in cancer development and progression.
Clin Exp Metastasis 2002
PMID:Identification and validation of metastasis-associated proteins in head and neck cancer cell lines by two-dimensional electrophoresis and mass spectrometry. 1209 Apr 72

Female transgenic FVB mice transfected with the mammary erbB-2/neu oncogene were injected 0.1 ml 0.9% solution of sodium chloride (control), 1 meg Vilon peptide (Lys-Glu) or Epitalon peptide (Ala-Glu-Asp-Glu), s.c., 5 days in succession once a month, beginning from the age of 2 months. The characteristics of mammary tumor induction in the control and experimental groups did not differ until the age of 9 months. Later on, Epitalon-treated mice revealed distinct inhibition of carcinogenesis. One tumor per animal was detected in 7% (control), 4% (Vilon) and 16% (Epitalon) (p < 0.05). Two or more tumors per animal were in 75%, 95% and 56%, respectively (p < 0.05). Largest diameter of mammary adenocarcinoma in the Epitalon group was smaller than in controls by 33% (p < 0.05). Although the number of mice with metastases to the lung in all three groups was practically identical, their incidence in the Vilon group was 2.6 times higher than in Epitalon-treated animals (p < 0.05). Largest diameter of metastasis in the Epitalon group was the smallest, too. Our data point to inhibition of mammary carcinogenesis by Epitalon in transgenic erbB-2/neu mice.
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PMID:[Effect of Epitalon and Vilon treatment on mammary carcinogenesis in transgenic erbB-2/NEU mice]. 1210 68

In view of the rising melanoma incidence and the absence of effective treatments for metastatic disease, there is an urgent need for new methods that allow the early detection of melanoma. To this end, in vivo detection by patient imaging with single-chain Fv (scFv) antibody fragments is an attractive diagnostic approach. However, high non-specific accumulation of scFvs in the kidney reduces image quality in this body area and prevents the use of scFvs for melanoma radioimmunotherapy. We have tested the effect of coadministration of L-lysine with (125)I-labelled scFvs against melanoma-associated proteoglycan on kidney accumulation in a nude mouse xenograft model. Coadministration of L-lysine had no significant effect on tumour accumulation of scFvs or blood clearance, but decreased kidney accumulation by factors of 2.25, 2.3, 6.3 and 5.8, respectively, at 1, 3, 6 and 18 h post-injection, and improved tumour to muscle contrast. The reduction in kidney accumulation was maximal at time points that can be extrapolated to patient studies. The time dependence of the effect suggests that further improvements could be achieved with an optimized dosing regimen. When combined with other strategies to reduce kidney accumulation of scFvs, coadministration of L-lysine has the potential to significantly improve tumour to kidney contrast.
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PMID:Reducing renal accumulation of single-chain Fv against melanoma-associated proteoglycan by coadministration of L-lysine. 1217 Jan 87

Scintigraphic imaging of metastatic melanoma lesions requires highly tumor-specific radiopharmaceuticals. Because both melanotic and amelanotic melanomas overexpress melanocortin-1 receptors (MC1R), radiolabeled analogues of alpha-melanocyte-stimulating hormone (alpha-MSH) are potential candidates for melanoma diagnosis. Here, we report the in vivo performance of a newly designed octapeptide analogue, [betaAla(3), Nle(4), Asp(5), D-Phe(7), Lys(10)]-alpha-MSH(3-10) (MSH(OCT)), which was conjugated through its N-terminal amino group to the metal chelator 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) to enable incorporation of radiometals (e.g., indium-111) into the peptide. DOTA-MSH(OCT) displayed high in vitro MC1R affinity (IC(50) 9.21 nM). In vivo [(111)In]DOTA-MSH(OCT) exhibited a favorable biodistribution profile after injection in B16-F1 tumorbearing mice. The radiopeptide was rapidly cleared from blood through the kidneys and, most importantly, accumulated preferentially in the melanoma lesions. Lung and liver melanoma metastases could be clearly imaged on tissue section autoradiographs 4 h after injection of [(111)In]DOTA-MSH(OCT). A comparative study of [(111)In]DOTA-MSH(OCT) with [(111)In]DOTA-[Nle(4), D-Phe(7)]-alpha-MSH ([(111)In]-DOTA-NDP-MSH) demonstrated the superiority of the DOTA-MSH(OCT) peptide, particularly for the amount of radioactivity taken up by nonmalignant organs, including bone, the most radiosensitive tissue. These results demonstrate that [(111)In]DOTA-MSH(OCT) is a promising melanoma imaging agent.
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PMID:DOTA alpha-melanocyte-stimulating hormone analogues for imaging metastatic melanoma lesions. 1285 39

Following the first synthesis of tritiated alpha-melanocyte-stimulating hormone (alpha-MSH, alpha-melanotropin) in 1974 by Medzihradszky et al., several alpha-MSH analogs were designed containing between 2 and 12 tritium atoms, the latter of which displayed a specific radioactivity of 12.21 GBq/micromol (330 Ci/mmol). Similarly, radioiodinated alpha-MSH analogs of high purity, full biological activity and a specific radioactivity of approximately 140 GBq/micromol were obtained. Although tritiated and radioiodinated alpha-MSH became indispensable tools as tracer molecules for numerous in vitro and in vivo studies, above all for receptor identification and characterization as well as for structure-activity studies, they did not fulfill the criteria required for therapeutic in vivo targeting of metastatic melanoma. Therefore, we recently developed alpha-MSH analogs containing the universal metal chelator 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) in different positions of the molecule. As DOTA can equally well incorporate diagnostic (e.g. (111)In, (67,68)Ga) and therapeutic (e.g. (90)Y, (67)Cu) radionuclides, DOTA-MSH compounds may serve for both melanoma scintigraphy and therapy. The analog DOTA-[betaAla(3), Nle(4), Asp(5), D-Phe(7), Lys(10)]-alpha-MSH(3-10) (DOTA-MSH(OCT)), which contains the metal chelator at its N-terminal end, displayed good in vitro MC1R affinity (IC(50) 9.21 nm). In vivo, [(111)In]DOTA-MSH(OCT) exhibited a favorable biodistribution profile after injection in B16-F1 tumor-bearing mice. The radiopeptide was rapidly cleared from blood through the kidneys and, most importantly, accumulated preferentially in the melanoma lesions. Lung and liver melanoma metastases could be clearly imaged on tissue section autoradiographs 4 h after injection of [(111)In]DOTA-MSH(OCT). A comparative study of [(111)In]DOTA-MSH(OCT) with [(111)In]DOTA-[Nle(4), D-Phe(7)]-alpha-MSH ([(111)In]DOTA-NDP-MSH) demonstrated the superiority of the DOTA-MSH(OCT) peptide, particularly with respect to the amount of radioactivity taken up by non-malignant organs, including bone, the most radiosensitive tissue. These results demonstrate that [(111)In]DOTA-MSH(OCT) specifically targets melanoma metastases and represents a lead compound for the development of therapeutic DOTA-MSH analogs.
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PMID:Radiolabeled alpha-melanocyte-stimulating hormone analogs for receptor-mediated targeting of melanoma: from tritium to indium. 1452 36

We carried out an open, non-randomized phase II study including all patients treated with whatever chemotherapy or combined modality regimen for whatever cancer who were in clinical objective response (complete response, CR, or partial response, PR) or stable disease (SD). The treatment consisted of administration of recombinant interleukin-2 (rIL-2) at a dose of 1.8 MIU subcutaneously three times/week (every other day) for the first 2 weeks of every month plus medroxyprogesterone acetate (MPA) 500 mg/day every other day plus antioxidant agents alpha-lipoic acid 300 mg/day and N-acetyl cysteine 1800 mg/day or carbocysteine lysine salt oral solution 2.7 g/day. The treatment was administered for 1 year except when progression of disease occurred. The primary study endpoints were to define clinical outcome, i.e. duration of response, survival (overall survival, OS and progression-free survival, PFS), the toxicity profile, and the evaluation of quality of life (QL). As secondary endpoints, we measured the changes of lymphocyte count, serum levels of proinflammatory cytokines, IL-2, C-reactive protein (CRP) and leptin, blood levels of reactive oxygen species (ROS) and antioxidant enzymes (glutathione peroxidase, GPx and superoxide dismertase, SOD). From July 1998 to June 2003, 42 patients were enrolled in the study (M/F ratio, 39/3; mean age, 62.5 years). Twenty (47.6%) patients were elderly (> 65 years). The majority of patients had either head and neck cancer or lung cancer, 88% had locally advanced or metastatic disease at diagnosis, and 76% had ECOG 0. Forty patients were previously treated with chemotherapy (27 also with radiotherapy), two with IL-2 and interfiron (IFN), one with endocrine therapy and one with only surgery. We obtained an objective response to maintenance treatment of 50%. Median duration of response was 19 months and median PFS was 33 months. Median duration of maintenance treatment was 12 months, median follow-up duration from diagnosis to June 2003 was 40 months, and median follow-up duration from study entry to June 2003 was 17 months. The median overall survival has not been reached. Toxicity was negligible. As for QL, a significant improvement of cognitive functions was observed, whereas all other functioning and symptom scales did not change significantly. As for laboratory parameters, absolute lymphocyte count increased significantly, IL-6, IL-1 beta, tumor necrosis factor-alpha, CRP, and fibrinogen decreased significantly whereas IL-2 and leptin increased significantly after treatment. ROS decreased significantly, whereas GPx increased significantly after treatment. Patients alive at study end showed a significant increase in absolute lymphocyte count, IL-2, leptin, and GPx and a significant decrease of proinflammatory cytokines, CRP, fibrinogen, and ROS, whereas patients who died before study end exhibited only a significant increase in absolute lymphocyte count, IL-2, and GPx and a significant decrease of ROS. Long-term combined maintenance therapy with rIL-2 + MPA + antioxidant agents is feasible, has a very low toxicity, and results in the improvement of clinical outcome, QL, and laboratory parameters.
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PMID:Subcutaneous interleukin-2 in combination with medroxyprogesterone acetate and antioxidants in advanced cancer responders to previous chemotherapy: phase II study evaluating clinical, quality of life, and laboratory parameters. 1456 91

Epigenetic silencing is now recognized as a 'third pathway' in Knudson's model of tumor-suppressor gene inactivation in cancer and can affect gene function without genetic changes. DNA methylation within gene promoters and alterations in histone modifications appear to be primary mediators of epigenetic inheritance in cancer cells. For selected genes, epigenetic changes are tightly related to neoplastic transformation in colorectal cancers (CRCs). In the colon, aberrant DNA methylation arises very early, initially in normal appearing mucosa, and may be part of the age-related field defect observed in sporadic CRCs. Aberrant methylation also contributes to later stages of colon cancer formation and progression through a hypermethylator phenotype termed CpG Island Methylator Phenotype (CIMP), which appears to be a defining event in about half of all sporadic tumors. CIMP+ CRCs are distinctly characterized by pathology, clinical and molecular genetic features. Histone modifications, recently recognized as a 'histone code' that affects chromatin structure and gene expression also play an important role in the establishment of gene silencing during tumorigenesis. DNA methylation and histone H3 lysine 9 hypoacetylation and methylation appear to form a mutually reinforcing silencing loop that contributes to tumor-suppressor gene inactivation in CRCs. Understanding epigenetic alterations as a driving force in neoplasia opens new fields of research in epidemiology, risk assessment, and treatment in CRCs.
Cancer Metastasis Rev
PMID:Epigenetic changes in colorectal cancer. 1500 Jan 47


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