| Autor: |
Kim TY; Lineberger Comprehensive Cancer Center, Department of Pharmacology, and Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599., Jackson S, Xiong Y, Whitsett TG, Lobello JR, Weiss GJ, Tran NL, Bang YJ, Der CJ |
| Jazyk: |
angličtina |
| Zdroj: |
Proceedings of the National Academy of Sciences of the United States of America [Proc Natl Acad Sci U S A] 2013 Oct 15; Vol. 110 (42), pp. 16868-73. Date of Electronic Publication: 2013 Sep 30. |
| DOI: |
10.1073/pnas.1306358110 |
| Abstrakt: |
DLC1 encodes a RhoA GTPase-activating protein and tumor suppressor lost in cancer by genomic deletion or epigenetic silencing and loss of DLC1 gene transcription. We unexpectedly identified non-small cell lung cancer (NSCLC) cell lines and tumor tissue that expressed DLC1 mRNA yet lacked DLC1 protein expression. We determined that DLC1 was ubiquitinated and degraded by cullin 4A-RING ubiquitin ligase (CRL4A) complex interaction with DDB1 and the FBXW5 substrate receptor. siRNA-mediated suppression of cullin 4A, DDB1, or FBXW5 expression restored DLC1 protein expression in NSCLC cell lines. FBXW5 suppression-induced DLC1 reexpression was associated with a reduction in the levels of activated RhoA-GTP and in RhoA effector signaling. Finally, FBXW5 suppression caused a DLC1-dependent decrease in NSCLC anchorage-dependent and -independent proliferation. In summary, we identify a posttranslational mechanism for loss of DLC1 and a linkage between CRL4A-FBXW5-associated oncogenesis and regulation of RhoA signaling. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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