Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1980-7-26
pubmed:abstractText
Studies on Morris hepatomas demonstrate that the specific activity of the enzymes of the Leloir pathway are subject to a variation in tumor tissue. The key enzyme of the galactose pathway, uridine diphosphogalactose 4'-epimerase, is elevated 5- to 9-fold in the rapidly growing and poorly differentiated Tumors 3924A and 7777; in line 9618A2, an even 28-fold increase was found. The observed correlation between enzyme activity, growth rate, and degree of differentiation of the hepatoma suggests that the differences are not coincidental variations. Conversely, the activity of uridine diphosphoglucose: galactose-1-phosphate uridyltransferase was diminished by 40 to 70% as compared to host liver, and the level of galactokinase showed only minor changes. The uptake of galactose and galactosamine by the hepatoma is heavily impaired, whereas the transport of other hexoses and amino sugars (2-deoxyglucose, L-fucose, N-acetylglucosamine, N-acetylmannosamine) is hardly affected. It appears that part of the carrier-mediated diffusion for hexoses is altered without a decisive impact on the whole system. Moreover, autoradiographic analysis of [14C]galactose-labeled tumor plasma membranes revealed a shift of the incorporation pattern from high- to lower-molecular-weight galactopolypeptides. Our results indicate that specific alterations of the D-galactose metabolism are a characteristic feature of Morris hepatomas.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0008-5472
pubmed:author
pubmed:issnType
Print
pubmed:volume
40
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2026-32
pubmed:dateRevised
2003-11-14
pubmed:meshHeading
pubmed:year
1980
pubmed:articleTitle
Alterations of D-galactose metabolism in Morris hepatomas.
pubmed:publicationType
Journal Article