Linked Life Data

7553622

Source:http://linkedlifedata.com/resource/pubmed/id/7553622

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
20
pubmed:dateCreated
1995-11-8
pubmed:abstractText
Loss of heterozygosity on 9p21, where the p16/CDKN2 tumor suppressor and the p15INK4B cell cycle regulator genes are located, is a common genetic alteration in bladder cancer. However, it has been difficult to demonstrate homozygous deletions and intragenic mutations in either of these two genes in primary transitional cell carcinomas (TCC) of the bladder. Similarly, colon cancer-derived cell lines have shown no homozygous deletions of the p16/CDKN2 locus in contrast to a wide variety of tumor-derived cell lines. We have investigated abnormal methylation of the 5' CpG islands of the p16/CDKN2 and p15INK4B genes as an alternative mechanism of inactivation of these genes in bladder and colon cancers. De novo methylation of the 5' CpG island of p16/CDKN2 was observed in 12 of 18 (67%) uncultured bladder TCCs and in 2 of 3 (67%) bladder cell lines. In contrast, only 1 of 10 (10%) colon carcinomas showed methylation of the 5' CpG island of p16/CDKN2. It was striking to find that this region was extensively methylated and the gene not expressed in the normal colonic mucosa of 6 of 10 (60%) patients with colon cancer, whereas 5 of the corresponding colon tumors showed no methylation and high levels of p16/CDKN2 expression. Our data show a significant correlation (P = 0.00001, two-sided) between the absence of p16/CDKN2 expression and methylation of its 5' CpG island in bladder tumors, cell lines, and normal colon mucosa. In contrast, no association was observed between expression and methylation status of the 5' CpG island of p15INK4B. Our results suggest that the p16/CDKN2 tumor suppressor gene may be inactivated by methylation of its 5' CpG island in TCCs of the bladder. We also present evidence of methylation of the 5' CpG island in this autosomal gene in normal colonic tissue.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0008-5472
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
55
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4531-5
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:7553622-Base Sequence, pubmed-meshheading:7553622-Carrier Proteins, pubmed-meshheading:7553622-Cell Cycle Proteins, pubmed-meshheading:7553622-Chromosomes, Human, Pair 9, pubmed-meshheading:7553622-Colonic Neoplasms, pubmed-meshheading:7553622-CpG Islands, pubmed-meshheading:7553622-Cyclin-Dependent Kinase Inhibitor p15, pubmed-meshheading:7553622-Cyclin-Dependent Kinase Inhibitor p16, pubmed-meshheading:7553622-DNA, Neoplasm, pubmed-meshheading:7553622-DNA Primers, pubmed-meshheading:7553622-Exons, pubmed-meshheading:7553622-Gene Expression Regulation, Neoplastic, pubmed-meshheading:7553622-Genes, pubmed-meshheading:7553622-Genes, Tumor Suppressor, pubmed-meshheading:7553622-Humans, pubmed-meshheading:7553622-Methylation, pubmed-meshheading:7553622-Molecular Sequence Data, pubmed-meshheading:7553622-RNA, Neoplasm, pubmed-meshheading:7553622-Transcription, Genetic, pubmed-meshheading:7553622-Tumor Cells, Cultured, pubmed-meshheading:7553622-Tumor Suppressor Proteins, pubmed-meshheading:7553622-Urinary Bladder Neoplasms
pubmed:year
1995
pubmed:articleTitle
Methylation of the 5' CpG island of the p16/CDKN2 tumor suppressor gene in normal and transformed human tissues correlates with gene silencing.
pubmed:affiliation
Urological Research Laboratory, USC/Norris Comprehensive Cancer Center, Los Angeles, CA 90033, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.