Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
18
pubmed:dateCreated
1996-10-24
pubmed:abstractText
p16 (CDKN2/MTS1/p16INK4a) is frequently deleted, methylated, or mutated in many malignancies including squamous cell carcinoma of the head and neck (HNSCC). p16 beta is an alternative transcript derived from a newly described exon (exon 1 beta) located more than 15 kb 5' to exon 1 of p16. Moreover, the p16 beta transcript theoretically encodes a protein distinct from p16 derived from a divergent reading frame putatively initiated in exon 1 beta. To test the contribution of both of these transcripts in carcinogenesis, full-length cDNA of p16 and p16 beta were cloned in separate vector constructs and then transfected into HNSCC cell lines characterized for p16 status (p16[+/+], p16[mut/-], and p16[methylated]). Transfection of either p16 or p16 beta resulted in marked growth inhibition in all three HNSCC lines tested, regardless of p16 status. However, p16 beta but not p16 inhibited the growth of HeLa cells, a cell line with inactive pRB due to expression of E7 papillomavirus protein. Moreover, transfection of all three HNSCC lines with either p16 or p16 beta resulted in a marked increase in cells in G0-G1 consistent with a cell cycle arrest in G1. These data are consistent with the hypothesis that p16 and p16 beta are growth-inhibitory genes active in HNSCC and that both act by blocking progression through the G1-S transition of the cell cycle. Furthermore, the suppressive effects of p16 beta on HeLa growth suggest that p16 beta mediates its effect independently from pRB.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0008-5472
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
56
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4119-23
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:8797577-Alternative Splicing, pubmed-meshheading:8797577-Base Sequence, pubmed-meshheading:8797577-Blotting, Western, pubmed-meshheading:8797577-Carrier Proteins, pubmed-meshheading:8797577-Cell Cycle, pubmed-meshheading:8797577-Cell Line, pubmed-meshheading:8797577-Cell Survival, pubmed-meshheading:8797577-Cyclin-Dependent Kinase Inhibitor p16, pubmed-meshheading:8797577-DNA Primers, pubmed-meshheading:8797577-Enzyme Inhibitors, pubmed-meshheading:8797577-Exons, pubmed-meshheading:8797577-Genes, Tumor Suppressor, pubmed-meshheading:8797577-Head and Neck Neoplasms, pubmed-meshheading:8797577-Humans, pubmed-meshheading:8797577-Molecular Sequence Data, pubmed-meshheading:8797577-Polymerase Chain Reaction, pubmed-meshheading:8797577-Protein Kinase Inhibitors, pubmed-meshheading:8797577-Transcription, Genetic, pubmed-meshheading:8797577-Transfection, pubmed-meshheading:8797577-Tumor Cells, Cultured
pubmed:year
1996
pubmed:articleTitle
p16 and p16 beta are potent growth suppressors of head and neck squamous carcinoma cells in vitro.
pubmed:affiliation
Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins Oncology Center, Johns Hopkins University, Baltimore, Maryland 21205, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't