Lin-28 homologue A (LIN28A) promotes cell cycle progression via regulation of cyclin-dependent kinase 2 (CDK2), cyclin D1 (CCND1), and cell division cycle 25 homolog A (CDC25A) expression in cancer.
J Biol Chem
; 287(21): 17386-17397, 2012 May 18.
Article
em En
| MEDLINE
| ID: mdl-22467868
ABSTRACT
The RNA-binding protein LIN28A regulates the translation and stability of a large number of mRNAs as well as the biogenesis of certain miRNAs in embryonic stem cells and developing tissues. Increasing evidence indicates that LIN28A functions as an oncogene promoting cancer cell growth. However, little is known about its molecular mechanism of cell cycle regulation in cancer. Using tissue microarrays, we found that strong LIN28A expression was reactivated in about 10% (7.1-17.1%) of epithelial tumors (six tumor types, n = 369). Both in vitro and in vivo experiments demonstrate that LIN28A promotes cell cycle progression in cancer cells. Genome-wide RNA-IP-chip experiments indicate that LIN28A binds to thousands of mRNAs, including a large group of cell cycle regulatory mRNAs in cancer and embryonic stem cells. Furthermore, the ability of LIN28A to stimulate translation of LIN28A-binding mRNAs, such as CDK2, was validated in vitro and in vivo. Finally, using a combined gene expression microarray and bioinformatics approach, we found that LIN28A also regulates CCND1 and CDC25A expression and that this is mediated by inhibiting the biogenesis of let-7 miRNA. Taken together, these results demonstrate that LIN28A is reactivated in about 10% of epithelial tumors and promotes cell cycle progression by regulation of both mRNA translation (let-7-independent) and miRNA biogenesis (let-7-dependent).
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Regulação Neoplásica da Expressão Gênica
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Ciclo Celular
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Neoplasias Epiteliais e Glandulares
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Ciclina D1
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Fosfatases cdc25
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Proteínas de Ligação a DNA
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Quinase 2 Dependente de Ciclina
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Proteínas de Neoplasias
Limite:
Female
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Humans
Idioma:
En
Ano de publicação:
2012
Tipo de documento:
Article