[Mutation and expression of SEMA3B and SEMA3F gene in nasopharyngeal carcinoma].
Ai Zheng
; 22(1): 16-20, 2003 Jan.
Article
em Zh
| MEDLINE
| ID: mdl-12561429
ABSTRACT
BACKGROUND & OBJECTIVE:
Though the molecular etiology of nasopharyngeal carcinoma(NPC) is currently unknown, evidence from both loss of heterozygosity analysis and functional studies suggested that there are NPC-associated tumor suppressor genes(TSGs) residing in chromosome 3p21.3. Recently, two members of semaphorin family, SEMA3B and SEMA3F gene, located at 3p21.3, were characterized as TSGs. Studies showed that SEMA3B and SEMA3F are capable of suppressing the growth of tumor cells and inducing apoptosis. Loss of SEMA3B mRNA expression or aberrant SEMA3F cellular localization were found in lung cancers. In order to investigate the involvement of SEMA3B and SEMA3F in NPC, the authors examined both mutation and expression of these two genes in NPC.METHODS:
The entire coding regions, the splice donor/acceptor sites, and partial regulatory regions of SEMA3B and SEMA3F gene were screened for mutations by PCR-sequencing in 21 primary NPC tumors and 2 NPC cell lines(CNE2 and SUNE1). The mRNA expression levels were determined by semi-quantitative RT-PCR analysis.RESULTS:
No somatic mutation was found in either SEMA3B or SEMA3F gene. However, two missense polymorphisms including Thr415Ile and lle242Met were found in SEMA3B in NPC. For the Thr415Ile polymorphism, the Ile allele type which leads to SEMA3B function defects was predominant in NPC with the allele frequency of 64% (27/42). SEMA3B mRNA was expressed in all 6 non-neoplastic nasopharyngeal epithelia, but was absent or down-regulated in 76% (16/21) of primary NPC tumors. No significant difference of SEMA3B expression was observed between NPC and noncancerous controls.CONCLUSION:
High frequency of SEMA3B expression alterations suggests that the inactivation of this gene was strongly associated with NPC. SEMA3B may be a tumor suppressor on 3p21.3 involved in NPC.
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Base de dados:
MEDLINE
Assunto principal:
Glicoproteínas de Membrana
/
Neoplasias Nasofaríngeas
/
Genes Supressores de Tumor
/
Mutação de Sentido Incorreto
/
Proteínas de Membrana
/
Proteínas do Tecido Nervoso
Limite:
Humans
Idioma:
Zh
Revista:
Ai Zheng
Assunto da revista:
NEOPLASIAS
Ano de publicação:
2003
Tipo de documento:
Article