Linked Life Data

8893877

Source:http://linkedlifedata.com/resource/pubmed/id/8893877

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5 Suppl 10
pubmed:dateCreated
1996-11-27
pubmed:abstractText
Cisplatin and gemcitabine both have activity in solid tumors, such as non-small cell lung, ovarian, and head and neck cancers. These drugs have the desired features needed to obtain synergistic activity, different side effect profiles, and mechanisms of action. Cisplatin acts by forming DNA-DNA cross-links (both intrastrand and interstrand) and DNA-protein cross-links; resistance to cisplatin is thought to be due to excision repair of the affected DNA. Gemcitabine acts by its incorporation into nucleic acids, leading to masked chain termination. By combining gemcitabine with cisplatin, it might be possible to achieve a better therapeutic effect than either drug alone and to bypass resistance to one or both drugs. Acquired resistance to gemcitabine was associated with a deoxycytidine kinase deficiency in vitro, but this was difficult to achieve in vivo. Proper scheduling may overcome intrinsic and transient resistance due to physiologic circumstances or aberrant biochemical properties. Preclinical in vitro and in vivo combination studies with cisplatin showed schedule- and model-dependent synergistic and additive effects between cisplatin and gemcitabine. Incorporation of gemcitabine into DNA might facilitate cisplatin-DNA adduct formation. Combining gemcitabine and cisplatin inhibited the DNA excision-repair process more than gemcitabine alone. This implies that if gemcitabine nucleotide is incorporated into the DNA strand, the action of the proofreading exonucleases is less efficient. In addition, both deoxyribonucleotide and ribonucleotide pools, essential for good functioning of DNA repair, are seriously depleted by gemcitabine. It is concluded that combining gemcitabine with cisplatin can be at least additive providing the right schedule is chosen, giving the best balance between acceptable toxicity and an enhanced antitumor activity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0093-7754
pubmed:author
pubmed:issnType
Print
pubmed:volume
23
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
16-24
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Preclinical combination therapy with gemcitabine and mechanisms of resistance.
pubmed:affiliation
Department of Oncology, Free University Hospital, Amsterdam, The Netherlands.
pubmed:publicationType
Journal Article, Review, Research Support, Non-U.S. Gov't