Prepublished online as a Blood First Edition Paper on October 24, 2002; DOI 10.1182/blood-2002-07-2034.
Previous Article | Table of Contents | Next Article 
Blood, 15 February 2003, Vol. 101, No. 4, pp. 1336-1343
HEMATOPOIESIS
The peripheral cannabinoid receptor Cb2, a novel oncoprotein,
induces a reversible block in neutrophilic
differentiation
Meritxell Alberich Jordà,
Bob Löwenberg, and
Ruud Delwel
From The Institute for Hematology, Erasmus Medical
Center, The Netherlands.
We previously identified a novel common virus integration
site, Evi11, by means of retroviral insertional
mutagenesis. We demonstrated that the gene encoding the peripheral
cannabinoid receptor (Cb2) is the potential target,
suggesting that Cb2 is a proto-oncogene. To elucidate a
role for this G protein-coupled receptor (GPCR) in leukemic
transformation we generated a Cb2-EGFP cDNA construct that
was introduced into 32D/G-CSF-R cells. These cells require interleukin
3 (IL-3) to proliferate in vitro, whereas in the presence of
granulocyte-colony-stimulating factor (G-CSF) they differentiate
toward mature neutrophils. We demonstrate that 32D/G-CSF-R/Cb2-EGFP
cells migrate in a transwell assay in reponse to the Cb2 ligand
2-arachidonoylglycerol (2-AG), indicating that the fusion protein was
functional. When cultured in the presence of G-CSF neutrophilic
differentiation of Cb2-EGFP-expressing 32D/G-CSF-R cells was
completely blocked. Moreover, a Cb2-specific antagonist fully recovered
the G-CSF-induced neutrophilic differentiation of 32D/G-CSF-R/Cb2-EGFP
cells. To investigate which signal transduction pathway(s) may be
involved in the block of neutrophilic maturation, differentiation
experiments were carried out using specific inhibitors of signaling
routes. Interestingly, full rescue of G-CSF-induced neutrophilic
differentiation was observed when cells were cultured with the
mitogen-induced extracellular kinase (MEK) inhibitors, PD98059 or
U0126, and partial recovery was detected with the phosphoinositide 3-kinase (PI3-K) inhibitor LY-294002. These studies demonstrate that
the Cb2 receptor is an oncoprotein that blocks neutrophilic differentiation when overexpressed in myeloid precursor cells. Cb2
appears to mediate its activity through MEK/extracellular signal-related kinase (ERK) and PI3-K pathways.

CiteULike Connotea Del.icio.us Digg Reddit Technorati What's this?
This article has been cited by other articles:

|
 |

|
 |
 
D. Zheng, A. M. Bode, Q. Zhao, Y.-Y. Cho, F. Zhu, W.-Y. Ma, and Z. Dong
The Cannabinoid Receptors Are Required for Ultraviolet-Induced Inflammation and Skin Cancer Development
Cancer Res.,
May 15, 2008;
68(10):
3992 - 3998.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
Q. Zhao, Z. He, N. Chen, Y.-Y. Cho, F. Zhu, C. Lu, W.-y. Ma, A. M. Bode, and Z. Dong
2-Arachidonoylglycerol Stimulates Activator Protein-1-dependent Transcriptional Activity and Enhances Epidermal Growth Factor-induced Cell Transformation in JB6 P+ Cells
J. Biol. Chem.,
July 22, 2005;
280(29):
26735 - 26742.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
P. Casellas
CB2, a paradigm for a novel class of "onco-GPCRs"?
Blood,
July 15, 2004;
104(2):
302 - 303.
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Alberich Jorda, N. Rayman, M. Tas, S. E. Verbakel, N. Battista, K. van Lom, B. Lowenberg, M. Maccarrone, and R. Delwel
The peripheral cannabinoid receptor Cb2, frequently expressed on AML blasts, either induces a neutrophilic differentiation block or confers abnormal migration properties in a ligand-dependent manner
Blood,
July 15, 2004;
104(2):
526 - 534.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
E. J. C. Rombouts, B. Pavic, B. Lowenberg, and R. E. Ploemacher
Relation between CXCR-4 expression, Flt3 mutations, and unfavorable prognosis of adult acute myeloid leukemia
Blood,
July 15, 2004;
104(2):
550 - 557.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. J. Erkeland, M. Valkhof, C. Heijmans-Antonissen, A. van Hoven-Beijen, R. Delwel, M. H. A. Hermans, and I. P. Touw
Large-Scale Identification of Disease Genes Involved in Acute Myeloid Leukemia
J. Virol.,
February 15, 2004;
78(4):
1971 - 1980.
[Abstract]
[Full Text]
[PDF]
|
 |
|
|
|