Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2004-3-12
pubmed:abstractText
We studied the transcriptional activity of p53 protein in 50 tissues of hepatocellular carcinoma (HCC) using a yeast functional assay. In this assay, red yeast colonies indicate that p53 protein cannot bind to its specific domain and has lost its transcriptional activity. We also clarified whether mutant p53 protein could inactivate wild-type p53 protein in a transdominant manner using a modified yeast assay. In addition, we examined whether immunohistochemically detectable p53 protein was functionally inactive. The incidence of p53 inactivation was significantly higher in tumors with capsular invasion. Out of 21 tumors diagnosed with p53 mutations, 11 exhibited >75% red colonies, and all contained missense mutations. In these tumors, p53 function was lost because there was supposedly no intact p53 gene on either allele. One missense mutant produced <60% red colonies, but it was also considered inactive as a p53 protein heterotetramer because of its transdominant activity. In 7 of the remaining 9 tumors, p53 was considered to be mutated on one allele and intact on the other. All of these 7 tumors contained nonsense or frameshift mutations and had no transdominant activity, which suggested that p53 function remained intact. Alternately, immunohistochemical analysis demonstrated that all of the tumors with missense mutations were positively immunostained, whereas those that contained nonsense or frameshift mutations were negatively stained. Consequently, positively immunostaining tumors mostly coincided with p53-inactive tumors. These yeast-based assays suggested that p53 function was retained in some mutant cases. Immunohistochemistry was helpful in screening functionally inactive p53 protein in HCCs.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0046-8177
pubmed:author
pubmed:issnType
Print
pubmed:volume
35
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
350-6
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:15017592-Adult, pubmed-meshheading:15017592-Aged, pubmed-meshheading:15017592-Aged, 80 and over, pubmed-meshheading:15017592-Apoptosis, pubmed-meshheading:15017592-Carcinoma, Hepatocellular, pubmed-meshheading:15017592-DNA, Neoplasm, pubmed-meshheading:15017592-DNA Mutational Analysis, pubmed-meshheading:15017592-Female, pubmed-meshheading:15017592-Genes, p53, pubmed-meshheading:15017592-Humans, pubmed-meshheading:15017592-Immunoenzyme Techniques, pubmed-meshheading:15017592-In Situ Nick-End Labeling, pubmed-meshheading:15017592-Liver Neoplasms, pubmed-meshheading:15017592-Male, pubmed-meshheading:15017592-Middle Aged, pubmed-meshheading:15017592-Mutation, pubmed-meshheading:15017592-RNA, Neoplasm, pubmed-meshheading:15017592-Reverse Transcriptase Polymerase Chain Reaction, pubmed-meshheading:15017592-Saccharomyces cerevisiae, pubmed-meshheading:15017592-Transcription, Genetic, pubmed-meshheading:15017592-Tumor Suppressor Protein p53
pubmed:year
2004
pubmed:articleTitle
Loss of p53 transcriptional activity in hepatocellular carcinoma evaluated by yeast-based functional assay: comparison with p53 immunohistochemistry.
pubmed:affiliation
Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Japan.
pubmed:publicationType
Journal Article, Comparative Study