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

A hybrid toxin targeted to melanotropin receptors and selectively cytotoxic to melanoma cell lines in vitro has recently been developed. The toxin, a recombinant fusion protein (designated DAB389-MSH), contains the peptide sequences of alpha-melanocyte-stimulating hormone (alpha-MSH) and the catalytic (cytotoxic; Fragment A) and lipophilic (part of Fragment B) domains of diphtheria toxin. In the present study, binding of DAB389-MSH to melanotropin receptors in biopsy specimens of human and mouse melanoma metastases was assessed by measuring its ability to inhibit binding of a radiolabeled, superpotent analogue of alpha-MSH (125I-[Nle4,D-Phe7]-alpha-MSH; 125I-NDP-MSH) and comparing its potency in this system with those of the established ligands NDP-MSH and alpha-MSH. Radioligand binding to tissue sections in vitro was localized and quantified by autoradiography and image analysis. DAB389-MSH inhibited binding of 125I-NDP-MSH to experimental murine B16-F1C23 melanoma metastasis tissue and to melanoma metastases of three patients. In both mouse and human melanoma tissues, concentration-response relationships for DAB389-MSH-mediated inhibition of 125I-NDP-MSH binding were parallel, and its maximal effects were comparable in magnitude, to those of NDP-MSH and alpha-MSH. Half-maximal peptide concentrations for inhibition of 125I-NDP-MSH binding to mouse melanoma tissue sections were: NDP-MSH, 0.63 nM; alpha-MSH, 3.14 nM; and DAB389-MSH, 10.1 nM. In human melanoma tissues, the respective half-maximal peptide concentrations for inhibition of 125I-NDP-MSH binding to mouse melanoma tissue sections were: NDP-MSH, 1.80 nM; alpha-MSH, 2.43 nM; and DAB389-MSH, 11.9 nM. Taken together, these results suggest that NDP-MSH, alpha-MSH, and DAB389-MSH bind to a common melanotropin receptor in human metastatic melanoma cells. Since previous work has shown that melanotropin receptors are detectable in melanoma metastases of about 80% of human patients, malignant melanoma cells of many patients may be susceptible to killing by the melanotropin receptor-targeted cytotoxin DAB389-MSH.
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PMID:Interaction of an alpha-melanocyte-stimulating hormone-diphtheria toxin fusion protein with melanotropin receptors in human melanoma metastases. 131 97

Pharmacological control of the angiogenic process (i.e., the neovascularization necessary for the growth and progression of tumors and metastases) is considered to be one of the most promising approaches to antineoplastic therapy. Endostatin, a 20-kDa protein derived from collagen XVIII, is one of the first recently discovered endogeneous antiangiogenic substances, but its cell targets and mechanism(s) of action are still unknown. We thought it would be interesting to test whether shorter peptides derived from endostatin might preserve its antiangiogenic activity. Four synthetic peptides corresponding to the sequences 6-49 (I), 50-92 (II), 93-133 (III), and 134-178 (IV) of human endostatin were tested for their ability to inhibit endothelial cell proliferation, migration, and both in vitro and in vivo angiogenesis. Fragment I (and fragment IV in the tests performed) was found to be fully biologically active in all of the angiogenesis assays, and sometimes showed even greater potency and efficacy than full-length human endostatin itself.
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PMID:Human endostatin-derived synthetic peptides possess potent antiangiogenic properties in vitro and in vivo. 1258 42

There is an urgent need to identify new therapeutic opportunities for metastatic melanoma. Fragment-based screening has led to the discovery of orally available, ATP-competitive AKT kinase inhibitors, AT13148 and CCT129254. These compounds also inhibit the Rho-kinases ROCK 1 and ROCK 2 and we show they potently inhibit ROCK activity in melanoma cells in culture and in vivo. Treatment of melanoma cells with CCT129254 or AT13148 dramatically reduces cell invasion, impairing both "amoeboid-like" and mesenchymal-like modes of invasion in culture. Intravital imaging shows that CCT129254 or AT13148 treatment reduces the motility of melanoma cells in vivo. CCT129254 inhibits melanoma metastasis when administered 2 days after orthotopic intradermal injection of the cells, or when treatment starts after metastases have arisen. Mechanistically, our data suggest that inhibition of ROCK reduces the ability of melanoma cells to efficiently colonize the lungs. These results suggest that these novel inhibitors of ROCK may be beneficial in the treatment of metastasis.
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PMID:Rho kinase inhibitors block melanoma cell migration and inhibit metastasis. 2584 Sep 82