Linked Life Data

1841712

Source:http://linkedlifedata.com/resource/pubmed/id/1841712

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1992-12-2
pubmed:abstractText
The importance of thioproteins, essential to the ribonucleotide reduction pathway, has been demonstrated in human primary and metastatic melanoma tissues. The thioredoxin reductase/thioredoxin and the glutathione reductase/glutathione/glutaredoxin electron transfer pathways represent alternative electron donors for ribonucleotide reductase and regulate the synthesis of deoxyribonucleotides, the substrates for DNA synthesis, in the S phase of the cell cycle. In addition to their important role in DNA synthesis and cell division, these thioproteins provide effective antioxidant defence against oxygen radicals and hydrogen peroxide. In human metastatic melanoma cells and tissues the thioredoxin reductase/thioredoxin system is located both in the cell cytosol and on plasma membranes and is under allosteric regulation by calcium. As a consequence, calcium plays an important role in determining the intracellular redox status, cell division and differentiation. Recently, the intracellular redox conditions have been shown to be important in the reaction of alkylating anti-tumour drugs such as the chloroethylnitrosoureas. In addition to previously established mechanisms, these highly reactive drugs inhibit thioredoxin reductase, glutathione reductase and ribonucleotide reductase by chloroethylation of their respective thiolate active sites. Incorporation of the 14C chloroethyl group in drug sensitive and resistant human metastatic melanoma cell lines depends on the redox status, with resistant cells being more oxic than sensitive cells. Thioredoxin reductase is 500-fold more sensitive than glutathione reductase to the newly developed nitrosourea, Fotemustine (diethyl-1-[3,2 chloroethyl]-3-nitrosoureido ethyl phosphonate). It has been shown that melanomas which respond to Fotemustine therapy contain more thioredoxin reductase whereas resistant metastases yielded the opposite result.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0960-8931
pubmed:author
pubmed:issnType
Print
pubmed:volume
1
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
159-67
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:articleTitle
New aspects in the pathophysiology of cutaneous melanoma: a review of the role of thioproteins and the effect of nitrosoureas.
pubmed:affiliation
Department of Dermatology, University of Hamburg, Germany.
pubmed:publicationType
Journal Article, Review, Research Support, Non-U.S. Gov't