Linked Life Data

19445022

Source:http://linkedlifedata.com/resource/pubmed/id/19445022

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2009-5-14
pubmed:abstractText
Previous gene expression profiles revealed the T-lymphocyte maturation-associated protein (MAL) gene as being frequently downregulated in head and neck cancer. To define the relationship between the MAL gene and the metastatic process, we evaluated the expression status of the gene in matched primary and metastatic tumors of head and neck cancer by semiquantitative reverse transcription-polymerase chain reaction. Furthermore, we aimed to identify potential genetic and epigenetic mechanisms associated with downregulation of MAL, including loss of heterozygosity (LOH), mutation, and hypermethylation. Thirty-five cell lines of University of Turko squamous cell carcinoma (UT-SCC) series derived from head and neck cancer, including nine pairs from matched primary and metastatic tumors, and 30 pairs of matched primary and metastatic tumor samples were analyzed. Twenty out of 35 (57%) cell lines showed downregulation of MAL expression, whereas no expression was found in 10 cell lines (29%). Considering matched primary and metastatic tumor-derived cell-line pairs, four pairs showed decreased expression only in metastasis-derived cells compared with their primary counterparts. Expression analysis of 21 tissue samples demonstrated decreased or no expression of MAL mRNA in 43% of metastatic tumors compared with matched primary tumors. Relating to mechanisms of downregulation, LOH was observed in 30% of primary tumors and 38% of their metastatic counterparts by a MAL-specific microsatellite marker. Furthermore, we found restoration of MAL mRNA after treatment with demethylating agent (5-aza-2'-deoxycytidine) in 9 (45%) out of 20 cell lines. No mutation was found in UT-SCC cell lines. In conclusion, our findings indicate selective downregulation of MAL expression in metastatic cells, suggesting the MAL gene as a new metastasis-suppressor candidate for head and neck cancer. LOH and hypermethylation appeared to be important mechanisms for inactivation of MAL function.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1349-7006
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
100
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
873-80
pubmed:meshHeading
pubmed-meshheading:19445022-Adult, pubmed-meshheading:19445022-Aged, pubmed-meshheading:19445022-Aged, 80 and over, pubmed-meshheading:19445022-Azacitidine, pubmed-meshheading:19445022-Carcinoma, Squamous Cell, pubmed-meshheading:19445022-Cell Line, Tumor, pubmed-meshheading:19445022-Female, pubmed-meshheading:19445022-Gene Expression Regulation, Neoplastic, pubmed-meshheading:19445022-Head and Neck Neoplasms, pubmed-meshheading:19445022-Heterozygote, pubmed-meshheading:19445022-Humans, pubmed-meshheading:19445022-Male, pubmed-meshheading:19445022-Membrane Transport Proteins, pubmed-meshheading:19445022-Middle Aged, pubmed-meshheading:19445022-Mutation, pubmed-meshheading:19445022-Myelin Proteins, pubmed-meshheading:19445022-Neoplasm Metastasis, pubmed-meshheading:19445022-Proteolipids, pubmed-meshheading:19445022-RNA, Messenger, pubmed-meshheading:19445022-Tumor Markers, Biological
pubmed:year
2009
pubmed:articleTitle
T-lymphocyte maturation-associated protein gene as a candidate metastasis suppressor for head and neck squamous cell carcinomas.
pubmed:affiliation
Department of Otolaryngology Head and Neck Surgery, Wakayama Medical University, Wakayama, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't