S-adenosylmethionine inhibits the growth of cancer cells by reversing the hypomethylation status of c-myc and H-ras in human gastric cancer and colon cancer.
Int J Biol Sci
; 6(7): 784-95, 2010 Dec 06.
Article
em En
| MEDLINE
| ID: mdl-21152119
ABSTRACT
A global DNA hypomethylation might activate oncogene transcription, thus promoting carcinogenesis and tumor development. S-Adenosylmethionine (SAM) serves as a major methyl donor in biological transmethylation events. The object of this study is to explore the influence of SAM on the status of methylation at the promoter of the oncogenes c-myc, H-ras and tumor-suppressor gene p16 (INK4a), as well as its inhibitory effect on cancer cells. The results indicated that SAM treatment inhibited cell growth in gastric cancer cells and colon cancer cells, and the inhibition efficiency was significantly higher than that in the normal cells. Under standard growth conditions, C-myc and H-ras promoters were hypomethylated in gastric cancer cells and colon cancer cells. SAM treatment resulted in a heavy methylation of these promoters, which consequently downregulated mRNA and protein levels. In contrast, there was no significant difference in mRNA and protein levels of p16 (INK4a) with and without SAM treatment. SAM can effectively inhibit the tumor cells growth by reversing the DNA hypomethylation on promoters of oncogenes, thus down-regulating their expression. With no influence on the expression of the tumor suppressor genes, such as P16, SAM could be used as a potential drug for cancer therapy.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
S-Adenosilmetionina
/
Neoplasias Gástricas
/
Proteínas Proto-Oncogênicas c-myc
/
Genes ras
/
Regiões Promotoras Genéticas
/
Metilação de DNA
/
Proliferação de Células
Limite:
Humans
Idioma:
En
Revista:
Int J Biol Sci
Assunto da revista:
BIOLOGIA
Ano de publicação:
2010
Tipo de documento:
Article