Involvement of elevated expression of multiple cell-cycle regulator, DTL/RAMP (denticleless/RA-regulated nuclear matrix associated protein), in the growth of breast cancer cells.
Oncogene
; 27(43): 5672-83, 2008 Sep 25.
Article
en En
| MEDLINE
| ID: mdl-18542055
ABSTRACT
To investigate the detailed molecular mechanism of mammary carcinogenesis and discover novel therapeutic targets, we previously analysed gene expression profiles of breast cancers. We here report characterization of a significant role of DTL/RAMP (denticleless/RA-regulated nuclear matrix associated protein) in mammary carcinogenesis. Semiquantitative RT-PCR and northern blot analyses confirmed upregulation of DTL/RAMP in the majority of breast cancer cases and all of breast cancer cell lines examined. Immunocytochemical and western blot analyses using anti-DTL/RAMP polyclonal antibody revealed cell-cycle-dependent localization of endogenous DTL/RAMP protein in breast cancer cells; nuclear localization was observed in cells at interphase and the protein was concentrated at the contractile ring in cytokinesis process. The expression level of DTL/RAMP protein became highest at G(1)/S phases, whereas its phosphorylation level was enhanced during mitotic phase. Treatment of breast cancer cells, T47D and HBC4, with small-interfering RNAs against DTL/RAMP effectively suppressed its expression and caused accumulation of G(2)/M cells, resulting in growth inhibition of cancer cells. We further demonstrate the in vitro phosphorylation of DTL/RAMP through an interaction with the mitotic kinase, Aurora kinase-B (AURKB). Interestingly, depletion of AURKB expression with siRNA in breast cancer cells reduced the phosphorylation of DTL/RAMP and decreased the stability of DTL/RAMP protein. These findings imply important roles of DTL/RAMP in growth of breast cancer cells and suggest that DTL/RAMP might be a promising molecular target for treatment of breast cancer.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Neoplasias de la Mama
/
Proteínas Nucleares
Tipo de estudio:
Risk_factors_studies
Límite:
Animals
/
Female
/
Humans
Idioma:
En
Revista:
Oncogene
Asunto de la revista:
BIOLOGIA MOLECULAR
/
NEOPLASIAS
Año:
2008
Tipo del documento:
Article
País de afiliación:
Japón