Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2000-4-27
pubmed:abstractText
We examined the frequency of p53 mutations in 38 oropharyngeal squamous cell carcinomas (SCC), using both a yeast functional assay and a conventional immunohistochemical staining method (IHC) to detect p53 mutations. We also explored the clinical importance of p53 mutations in oropharyngeal SCC. An accumulation of p53 protein was detected in 17 of the 38 (45%) tumors by IHC, whereas the yeast-based assay detected 6 additional p53 mutations, for a total of 23 tumors (61%) with p53 mutations. The cDNA sequencing analysis revealed that the 6 mutations undetected by IHC consisted of 3 frameshift, 1 nonsense and 2 missense mutations. Thus, the yeast functional assay was more sensitive than conventional IHC for detecting p53 mutations. Subsequently, the relationship between p53 mutations and the clinico-pathological parameters in oropharyngeal SCC was evaluated using the results of the functional assay. Mutation of p53 was not associated with the patient age, sex, tumor stage or degree of tumor cell differentiation. Interestingly, heavy drinking had a significant positive correlation with the p53 mutation, but heavy smoking did not, suggesting that prolonged exposure to alcohol is more related to p53 mutation in oropharyngeal SCC than to tobacco consumption. Radiation sensitivity was examined by comparing tumor size on magnetic resonance images before and after completion of therapy with 45 Gy radiation, in the 18 cases of T2 oropharyngeal SCC that were initially treated by radiotherapy. The results showed that tumors with wild-type p53 decreased in size significantly compared to those with mutant p53. In 33 patients treated with curative intent, the overall survival after the completion of therapy was better in patients with a wild-type p53 tumor than in patients with a mutant p53 tumor. We conclude that p53 mutation is associated with radiation resistance and a decreased probability of survival in oropharyngeal SCC.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0020-7136
pubmed:author
pubmed:copyrightInfo
Copyright 2000 Wiley-Liss, Inc.
pubmed:issnType
Print
pubmed:day
20
pubmed:volume
89
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
187-93
pubmed:dateRevised
2009-11-3
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Clinical significance of p53 functional loss in squamous cell carcinoma of the oropharynx.
pubmed:affiliation
Department of Otolaryngology, Kumamoto University School of Medicine, Kumamoto, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't