Chronic Lymphocytic Leukemia |
* Institut de Génétique Moléculaire de Montpellier, UMR5535, Montpellier, France
° Department of Statistics and Operation Research, University of Jaén, Spain
# Laboratory for Experimental Oncology and Radiobiology, Amsterdam Medical Center, Amsterdam, The Netherlands
@ Service dHématologie Biologique, Groupe Hospitalier La Pitié-Salpêtrière, Paris, France
Correspondence: Lourdes Planelles, PhD, Department of Immunology and Oncology, Centro Nacional de Biotecnologia/CSIC, Darwin 3, UAM Campus de Cantoblanco, 28049 Madrid, Spain. Phone: international +34.915854855. Fax: international +34.9.13720493. E-mail: lplanelles{at}cnb.uam.es
|
|
|---|
Key words: LLC, APRIL serum levels, overall survival, prognostic factor.
BLyS is a fundamental survival factor for transitional and mature B cells, whereas APRIL mainly affects B-1 cell activity, humoral responses and immunoglobulin class switching.1 We recently reported that aging APRIL transgenic mice develop B-1 cell-associated tumors that are highly reminiscent of human CLL; our initial analysis showed increased levels of circulating APRIL in CLL patients (n=22) compared to healthy donors.2 Two other reports described that BLyS and APRIL can act in an autocrine manner in CLL tumor cells, promoting cell survival.3,4 In addition, APRIL produced by inflammatory cells that infiltrate tumor lesions appears to contribute to disease in B cell lymphoma.5
To further evaluate APRIL and BLyS implication in CLL, we performed a retrospective study of a cohort of 95 patients diagnosed with CLL according to NCI criteria.6 After informed consent was obtained, peripheral blood samples were collected from 1991 to 2005, aliquoted and frozen. As a control, 32 sera from age- and sex-matched healthy donors were processed in the same manner. The sera tested were of patients at different stages (A, B and C), but mostly (80%) of untreated patients at either stage A or B. Circulating APRIL was measured by ELISA as described2 and the mean APRIL serum level was 10.5 ng/ml in healthy donors (range=1.8–25.3 ng/mL; n=32) and 64.5 ng/mL in CLL patients (range=1.5–208.5 ng/mL; n=95; p<0.0001; Figure 1A); 75% of all CLL patients showed an increase in circulating APRIL protein compared to controls. We also observed significant differences in APRIL levels in CLL patients grouped by Binets staging; the mean APRIL serum level was 53.5 ng/mL in stage A patients (n=57) and 79.9 ng/mL in B/C patients (n=37; p=0.02).
![]() View larger version (10K): [in a new window] [Download PPT slide] |
Figure 1. Serum APRIL (A) and BLyS (A) levels in CLL. The retrospective study included 95 patients diagnosed with typical CLL according to NCI criteria6 and 32 sera from age- and sex-matched healthy donors. Circulating APRIL and BLyS were measured by ELISA. Sera were tested three times each; solid lines represent the mean value for each group. (C) Kaplan-Meier curves of overall survival based on serum APRIL levels for all patients.
|
To evaluate the clinical relevance of circulating APRIL on CLL, we divided the patient cohort according to the median APRIL serum level. Patients were considered APRILhigh when serum APRIL concentration
56 ng/mL or APRILlow when APRIL concentration was <56 ng/mL. A description of our CLL patient population and distribution according to the median APRIL levels is shown in Table 1. Fishers exact test showed no significant association between APRIL levels and Binets stage or VH mutational status when all patients where considered. Nevertheless, when analyzing the association of APRIL levels and VH mutational status in subgroups defined by Binets stage, we found that B/C patients with unmutated VH genes were associated with higher serum APRIL levels than B/C patients with VH mutated genes (p=0.04).
|
View this table: [in a new window] [Download PPT slide] |
Table 1. CLL patient distribution related to APRIL levels.
|
Funding: MH and LPC were supported by Action Concertee Incitative Jeunes Chercheurs (ACI), Association pour la Recherche sur le Cancer (ARC), Fondation Recherche Médicale (FRM), Fondation de France and Ramón y Cajal Program. JPM was sponsored by a Dutch Cancer Society grant (2003-2812).
|
|
|---|
This article has been cited by other articles:
![]() |
J Morel, C Roubille, L Planelles, C Rocha, L Fernandez, C Lukas, M Hahne, and B Combe Serum levels of tumour necrosis factor family members a proliferation-inducing ligand (APRIL) and B lymphocyte stimulator (BLyS) are inversely correlated in systemic lupus erythematosus Ann Rheum Dis, June 1, 2009; 68(6): 997 - 1002. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. C. Kimberley, L. van Bostelen, K. Cameron, G. Hardenberg, J. A. Marquart, M. Hahne, and J. P. Medema The proteoglycan (heparan sulfate proteoglycan) binding domain of APRIL serves as a platform for ligand multimerization and cross-linking FASEB J, May 1, 2009; 23(5): 1584 - 1595. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Bonci, M. Musumeci, V. Coppola, A. Addario, C. Conticello, M. Hahne, M. Gulisano, F. Grignani, and R. De Maria Blocking the APRIL circuit enhances acute myeloid leukemia cell chemosensitivity Haematologica, December 1, 2008; 93(12): 1899 - 1902. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Hardenberg, L. Fernandez, J. Hendriks, K. Chebli, C. Jacquet, M. Sitbon, M. Hahne, and J. P. Medema APRIL facilitates viral-induced erythroleukemia but is dispensable for T cell immunity and lymphomagenesis J. Leukoc. Biol., August 1, 2008; 84(2): 380 - 388. [Abstract] [Full Text] [PDF] |
||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||