Diapositive%201

1
Comparison of Chronic Lymphocytic Leukemia
patients expressing high or low level of ZAP70
mRNA new prognostic factors, differences in
microRNA expression and interaction with the
microenvironment.
B. Stamatopoulos, B. Haibe-Kains, C. Equeter, N.
Meuleman, A. Sorée, C. De Bruyn, D. Hanosset, D.
Bron, P. Martiat, L. Lagneaux
Experimental Hematology, Institut Jules Bordet
(ULB)
23rd annual general meeting of the BHS, January
25, 2008
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Introduction

• CLL 2 distinct evolutions

• Prognostic factors IgVH mutational status
• and its surrogate ZAP70, LPL,

• ZAP70 measured by flow cytometry

3

• ZAP70 measured by quantitative real time PCR

TFS
OS
(Stamatopoulos B. et al, Clin. Chem, 2007)
4
Aims of the study

• To determine gene expression profiles linked to
  ZAP70 expression using Affymetrix technology

• To find genes associated with prognosis but
  also with biology

• To confirm differentially expressed microRNA
  and link them to TFS and OS

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Patient selection
ZAP70 mRNA expression among 108 patients by qPCR
Low
high
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Patient characteristics
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Methods
Purification with anti-CD19 magnetic beads
98-100 purity
blood collection
PBMC gradient isolation
(1,5µg)
RNA extraction

• - 50 000 oligonucleotides
• 47 000 transcripts
• 39 500 human genes

Affymetrix Protocole
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Results

• 937 probe sets with Plt0.05
• 135 probe sets with Plt0.001
• 43 probe sets with FDRlt10
• Top of the list

qPCR validation
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Novel genes and clinical outcome
TFS OS
but also TLR7, LPL, PCDH9, MYBL1,
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PDE8A a novel therapeuthic target ?
Control (ethanol)
Dipyridamol 15µM
Propidium Ioide - PE
Annexine V - FITC
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Gene set enrichment analysis
Lagneaux L. et al, Blood, 1998 Ghia P., Semin
Cancer Biol, 2002
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ZAP70 and CXCR4 modulation by ME
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Adhesion and migration
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MicroRNA expression
TFS OS
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Conclusions

• ZAP70 and patients
• distinc gene expression
  profiles
• new prognostic factors genes and microRNA
• new potential therapeutic target
• gene set implicated in migration and adhesion
• ZAP70 better adhesion and migration
  capacities into their microenvironment
• Better survival of ZAP70 cells and the
  agressiveness of the disease

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Acknowledgments
PhD director Laurence Lagneaux and ALL MEMBERS
of the Laboratory of Experimental Hematology of
Pr. Philippe Martiat
CLL sample collection Nathalie
Meuleman Dominique Bron Philippe Martiat Philippe
Herman (St-Pierre Hospital) Alain Kentos (Erasme
Hospital ULB)
(Bordet Institute ULB)
This work was financed by F.R.I.A. grant and the
Télévie fund, both of which are affiliated with
the F.R.S-F.N.R.S.
Thank you for your attention.