HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 281, Issue 14, 9238-9250, April 7, 2006

This Article Full Text Full Text (PDF) All Versions of this Article: 281/14/9238    most recent M600228200v1 Submit a Letter to Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Calipel, A. Articles by Mascarelli, F. Search for Related Content PubMed PubMed Citation Articles by Calipel, A. Articles by Mascarelli, F. Social Bookmarking                      What's this?

Extracellular Signal-regulated Kinase-dependent Proliferation Is Mediated through the Protein Kinase A/B-Raf Pathway in Human Uveal Melanoma Cells^*

Armelle Calipel¹, Frédéric Mouriaux, Anne-Lise Glotin¹, François Malecaze^¶, Anne-Marie Faussat^||, and Frédéric Mascarelli²

From the INSERM U598 and ^||IFR58, Institut Biomédical des Cordeliers, Paris 75006, France, Service d'Ophtalmologie, CHU Caen 14000, France, ^¶Service d'Ophthalmologie, Hopital Purpan, CHRU, Toulouse 31000, France

Mutated B-Raf-mediated constitutive activation of ERK1/2 is involved in about 66% of cutaneous melanoma. By contrast, activating mutations in B-RAF are rare in ocular melanoma. This study aimed to determine the role of wild-type B-Raf (^WTB-Raf) in uveal melanoma cell growth. We used cell lines derived from primary tumors of uveal melanoma to assess the role of ^WTB-Raf in cell proliferation and to characterize its upstream regulators and downstream effectors. Melanoma cell lines expressing ^WTB-Raf and ^WTRas grew with similar proliferation rates, showed constitutive activation of ERK1/2, and had similar levels of B-Raf expression and B-Raf kinase activity as melanoma cell lines expressing the activating V600E mutation (^V600EB-Raf). They were equally as sensitive to pharmacological inhibition of MEK1/2 for cell proliferation and transformation as ^V600EB-Raf cells. siRNA-mediated depletion of Raf-1 did not affect either ERK1/2 activation, whereas siRNA-mediated depletion of B-Raf reduced cell proliferation by up to 65% through the inhibition of ERK1/2 activation, irrespective of the mutational status of B-Raf. Pharmacological inhibition of cAMP-dependent protein kinase (PKA) and siRNA-mediated depletion of PKA greatly reduced B-Raf activity, ERK1/2 activation, and cell proliferation in ^WTB-Raf cells, whereas it did not affect ^V600EB-Raf cells, demonstrating a key role of PKA in mediating ^WTB-Raf/ERK signaling for uveal melanoma cell growth. Moreover, inactivation or depletion of PKA did not affect Rap-1 activity, and Rap-1 depletion did not affect either B-Raf activity or ERK1/2 activation. This ruled out a role for Rap1 in the PKA-mediated B-Raf/ERK activation in ^WTB-Raf cells. Finally, we demonstrated the importance of cyclin D1 in mediating PKA/^WTB-Raf signaling for cell proliferation. Altogether, our results suggest that the PKA/B-Raf pathway is a potential target for therapeutic strategies against ^WTB-Raf-expressing uveal melanoma.

Received for publication, January 10, 2006

^* This work was supported by grants from the Association pour la Recherche sur le Cancer. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

¹ Supported by fellowships from the French Ministère de la Recherche.

² To whom correspondence should be addressed: Institut Biomédicaldes Cordeliers, INSERM U598, 15 Rue de l'Ecole de Médecine, Paris 75006, France. E-mail: fmascar{at}infobiogen.fr.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				G. Lefevre, N. Babchia, A. Calipel, F. Mouriaux, A.-M. Faussat, S. Mrzyk, and F. Mascarelli Activation of the FGF2/FGFR1 Autocrine Loop for Cell Proliferation and Survival in Uveal Melanoma Cells Invest. Ophthalmol. Vis. Sci., March 1, 2009; 50(3): 1047 - 1057. [Abstract] [Full Text] [PDF]

				M. D. Onken, L. A. Worley, M. D. Long, S. Duan, M. L. Council, A. M. Bowcock, and J. W. Harbour Oncogenic Mutations in GNAQ Occur Early in Uveal Melanoma Invest. Ophthalmol. Vis. Sci., December 1, 2008; 49(12): 5230 - 5234. [Abstract] [Full Text] [PDF]

				A. S. Rocha, S. Paternot, K. Coulonval, J. E. Dumont, P. Soares, and P. P. Roger Cyclic AMP Inhibits the Proliferation of Thyroid Carcinoma Cell Lines through Regulation of CDK4 Phosphorylation Mol. Biol. Cell, November 1, 2008; 19(11): 4814 - 4825. [Abstract] [Full Text] [PDF]

				Y. Dai, S. Chen, X.-Y. Pei, J. A. Almenara, L. B. Kramer, C. A. Venditti, P. Dent, and S. Grant Interruption of the Ras/MEK/ERK signaling cascade enhances Chk1 inhibitor-induced DNA damage in vitro and in vivo in human multiple myeloma cells Blood, September 15, 2008; 112(6): 2439 - 2449. [Abstract] [Full Text] [PDF]

				N. Babchia, A. Calipel, F. Mouriaux, A.-M. Faussat, and F. Mascarelli 17-AAG and 17-DMAG-Induced Inhibition of Cell Proliferation through B-Raf Downregulation in WTB-Raf-Expressing Uveal Melanoma Cell Lines Invest. Ophthalmol. Vis. Sci., June 1, 2008; 49(6): 2348 - 2356. [Abstract] [Full Text] [PDF]

				W. Maat, S. H. W. Beiboer, M. J. Jager, G. P. M. Luyten, N. A. Gruis, and P. A. van der Velden Epigenetic Regulation Identifies RASEF as a Tumor-Suppressor Gene in Uveal Melanoma Invest. Ophthalmol. Vis. Sci., April 1, 2008; 49(4): 1291 - 1298. [Abstract] [Full Text] [PDF]

				G. Ambrosini, H. S. Cheema, S. Seelman, A. Teed, E. B. Sambol, S. Singer, and G. K. Schwartz Sorafenib inhibits growth and mitogen-activated protein kinase signaling in malignant peripheral nerve sheath cells Mol. Cancer Ther., April 1, 2008; 7(4): 890 - 896. [Abstract] [Full Text] [PDF]

				B. Wang, Y. Yang, and P. A. Friedman Na/H Exchange Regulatory Factor 1, a Novel AKT-associating Protein, Regulates Extracellular Signal-regulated Kinase Signaling through a B-Raf-Mediated Pathway Mol. Biol. Cell, April 1, 2008; 19(4): 1637 - 1645. [Abstract] [Full Text] [PDF]

				M. Ye, D. Hu, L. Tu, X. Zhou, F. Lu, B. Wen, W. Wu, Y. Lin, Z. Zhou, and J. Qu Involvement of PI3K/Akt Signaling Pathway in Hepatocyte Growth Factor-Induced Migration of Uveal Melanoma Cells Invest. Ophthalmol. Vis. Sci., February 1, 2008; 49(2): 497 - 504. [Abstract] [Full Text] [PDF]

				W. Maat, E. Kilic, G. P. M. Luyten, A. de Klein, M. J. Jager, N. A. Gruis, and P. A. Van der Velden Pyrophosphorolysis Detects B-RAF Mutations in Primary Uveal Melanoma Invest. Ophthalmol. Vis. Sci., January 1, 2008; 49(1): 23 - 27. [Abstract] [Full Text] [PDF]

				J. R. Latendresse, L. Muskhelishvili, A. Warbritton, and W. H. Tolleson Two Cases of Uveal Amelanotic Melanoma in Transgenic Tyr-HRAS+ Ink4a/Arf Heterozygous Mice Toxicol Pathol, October 1, 2007; 35(6): 825 - 830. [Abstract] [Full Text] [PDF]

				R. Rao, R. Redha, I. Macias-Perez, Y. Su, C. Hao, R. Zent, M. D. Breyer, and A. Pozzi Prostaglandin E2-EP4 Receptor Promotes Endothelial Cell Migration via ERK Activation and Angiogenesis in Vivo J. Biol. Chem., June 8, 2007; 282(23): 16959 - 16968. [Abstract] [Full Text] [PDF]

				G. Bartholomeusz, M. Talpaz, W. Bornmann, L.-Y. Kong, and N. J. Donato Degrasyn Activates Proteasomal-Dependent Degradation of c-Myc Cancer Res., April 15, 2007; 67(8): 3912 - 3918. [Abstract] [Full Text] [PDF]