Linked Life Data

2403032

Source:http://linkedlifedata.com/resource/pubmed/id/2403032

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1990-10-26
pubmed:abstractText
Magnetic resonance spectroscopy (MRS) uniquely provides noninvasive access to chemistry in vivo. 31P MRS can be used to monitor the high energy phosphates--phosphocreatine (PCr) and ATP, and their breakdown product--Pi, in situ in animals or patients. In several experimental tumor lines in animals it has been shown that the PCr/ATP and other related ratios steadily decline as the tumor increases in size, and that this effect is reversed when the tumor is treated with a therapeutic modality to which it responds. Acid extracts of freeze-clamped tumors at different stages of growth have confirmed these MRS observations and give additional information on related compounds such as creatine and ADP. Results show that, in the tumors studied, at least 80% of the ADP and about 40% of the Pi are bound and not in solution in the cytosol. Histological sections have indicated that the MRS response to endocrine therapy, in an NMU-induced estrogen-sensitive mammary tumor model, precedes any histological changes or any measurable regression. If these findings can be translated into a clinical setting, this may mean that MRS can be used in the clinic as an early predictor of tumor responsiveness to treatment. In untreated tumor growth, the cause of the decrease in PCr and ATP relative to Pi is probably due to the tumors outgrowing their blood supply and the cells becoming increasingly hypoxic. The PCr is lost more rapidly than ATP, indicating that the equilibrium in the creatine kinase reaction is maintained in these tumors. When the tumor is treated, cellular growth ceases and the requirement for oxygen and other nutrients is greatly reduced. This would allow the cellular energy reserves to be repleted and thus lead to the paradoxical improvement in the high energy phosphate status of a tumor that is about to regress.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0065-2571
pubmed:author
pubmed:issnType
Print
pubmed:volume
30
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
217-30
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Monitoring tumor growth and regression by 31P magnetic resonance spectroscopy.
pubmed:affiliation
Department of Cellular and Molecular Sciences, St. George's Hospital Medical School, London, U.K.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't