|
|
Prepublished online as a Blood First Edition Paper on January 30, 2003; DOI 10.1182/blood-2002-08-2501.
Previous Article | Table of Contents | Next Article 
Blood, 1 June 2003, Vol. 101, No. 11, pp. 4561-4568
NEOPLASIA
Tetrocarcin-Ainduced ER stress mediates apoptosis in B-CLL cells via a Bcl-2independent pathway
Gabriele Anether,
Inge Tinhofer,
Monika Senfter, and
Richard Greil
From the Laboratory of Molecular Cytology, Department of Hematology and Oncology, University of Innsbruck, Austria; and the Tyrolean Cancer Research Institute at the University of Innsbruck, Austria.
Tetrocarcin-A (TC-A), an antibiotic agent isolated from actinomycetes, has recently been described to antagonize Bcl-2 functions, thereby sensitizing tumor cells to cell death signals under control of Bcl-2. In this study, we analyzed the direct proapoptotic effect of TC-A in the B-chronic lymphocytic leukemia (B-CLL) model. We focused on the signal cascade triggered by TC-A in B-CLL cells and identified activated mitochondrial as well as endoplasmatic reticulum (ER) stress signals. The expression levels of known effector molecules mediating mitochondrial signaling, such as Bax and Bid, and the antagonistic molecule Bcl-2 did not influence sensitivity of B-CLL cells to TC-A. Furthermore, the molecular chaperone and sensor of ER stress, HSP70, though significantly up-regulated in B-CLL cells undergoing TC-Atriggered apoptosis, was ineffective to exert its anti-apoptotic function described in multiple cell death pathways. Autologous T cells of B-CLL patients were significantly less sensitive to TC-A as were also T cells from healthy donors when compared with their normal B-cell fraction. Furthermore, sensitivity of B-CLL cells to TC-A treatment in vitro was dependent neither on the expression levels of CD38a prognostic factor for survival of B-CLL patients as well as for their response to therapynor on the clinical stage or pretreatment status of patients. From our data showing that TC-A induced a cell death pathway via ER stress preferentially in B cells and that it acted independently of important markers of drug sensitivity and of clinical markers, we conclude that TC-A might represent an attractive candidate drug for further evaluation in preclinical trials.

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

|
 |

|
 |
 
S. LUST, B. VANHOECKE, M. VAN GELE, J. BOELENS, H. VAN MELCKEBEKE, M. KAILEH, W. VANDEN BERGHE, G. HAEGEMAN, J. PHILIPPE, M. BRACKE, et al.
Xanthohumol Activates the Proapoptotic Arm of the Unfolded Protein Response in Chronic Lymphocytic Leukemia
Anticancer Res,
October 1, 2009;
29(10):
3797 - 3805.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. Fang, Y. Zhang, L. Huang, X. Jia, Q. Zhang, X. Zhang, G. Tang, and W. Liu
Cloning and Characterization of the Tetrocarcin A Gene Cluster from Micromonospora chalcea NRRL 11289 Reveals a Highly Conserved Strategy for Tetronate Biosynthesis in Spirotetronate Antibiotics
J. Bacteriol.,
September 1, 2008;
190(17):
6014 - 6025.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. S. Carew, S. T. Nawrocki, Y. V. Krupnik, K. Dunner Jr, D. J. McConkey, M. J. Keating, and P. Huang
Targeting endoplasmic reticulum protein transport: a novel strategy to kill malignant B cells and overcome fludarabine resistance in CLL
Blood,
January 1, 2006;
107(1):
222 - 231.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
D. T. Jones, E. Addison, J. M. North, M. W. Lowdell, A. V. Hoffbrand, A. B. Mehta, K. Ganeshaguru, N. I. Folarin, and R. G. Wickremasinghe
Geldanamycin and herbimycin A induce apoptotic killing of B chronic lymphocytic leukemia cells and augment the cells' sensitivity to cytotoxic drugs
Blood,
March 1, 2004;
103(5):
1855 - 1861.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. L. Aron, M. R. Parthun, G. Marcucci, S. Kitada, A. P. Mone, M. E. Davis, T. Shen, T. Murphy, J. Wickham, C. Kanakry, et al.
Depsipeptide (FR901228) induces histone acetylation and inhibition of histone deacetylase in chronic lymphocytic leukemia cells concurrent with activation of caspase 8-mediated apoptosis and down-regulation of c-FLIP protein
Blood,
July 15, 2003;
102(2):
652 - 658.
[Abstract]
[Full Text]
[PDF]
|
 |
|
|
|