Download (microenvironment) of the CLL cell

The “outside” (microenvironment)
of the CLL cell: new insights into disease
biology and new therapeutic targets
Versteckspiel im Wald
by Friedrich Eduard Meyerheim (1808-1879)
Conventional therapies
Stromal
cell
protect
CLL
Jan Burger, MD PhD
Department of Leukemia
MD Anderson Cancer Center
Microenvironment in CLL


From: Soma LA et al,
Human Pathology.
2006;37:152-159
From: PE Patten et al.
Blood. 2008;111:5173-81
Messmer BT, et al.
J Clin Invest. 115(3): 755-764, 03/2005
Larger proliferating CLL
cells form proliferation
centers (pseudofollicles),
a hallmark finding in CLL
Within pseudofollicles,
CLL cells are in close
contact with accessory
cell (stomal cells, T cells)
CLL#1
CLL#2
CLL#3
normal
tonsil
From: J Rual et al. Clinical Cancer Research 12, 5622-31, 2006
Bhattacharya and Mertens et al., Leukemia (2011) 25, 722–726
Microenvironment in CLL:
a-SMA and CD14/68+ cells
CLL in vitro model: BMSC co-cultures
• Standardized CLL-stroma coculture conditions for drug
testing
• Ideal for testing drug
combinations
From: Sivina et al., Leukemia 26:1812-20, 08/2012
IN VITRO MODEL : Nurselike cells
BAFF-R, BCMA, TACI*
BAFF, APRIL
CXCR5¶
BCR
#
CXCL13 CXCL12
?antigen
CD31,
plexin-B1
CXCR4†
CD38, CD100‡
* Nishio M et al. Blood 106:1012-20, 2005
¶ Burkle A et al. Blood 110:3316-25, 2007
† Burger JA et al. Blood 96, 2655-63, 2000
‡ Deaglio S et al. Blood 105(8):3042-50, 2005
# Burger JA et al. Blood. 113:3050-8, 2009
The lymph node microenvironment
promotes BCR signaling
CCL4
CCL3

CLL cells isolated from lymph
nodes showed upregulation of
CCL3 and CCL4

LN signature GEPs have a
remarkable similarity to GEP of
CLL cells after co-cultured with
nurselike cells, including
upregulation of CCL3, CCL4,
EGR2, EGR3, and MYC
From: Y Herishanu et al., Blood. 2011 Jan 13;117(2):563-74
Summary: molecular interactions
in the CLL microenvironment



From: Burger JA et al., Blood. 2009 Oct 15;114(16):3367-75
The moleculoar
interactions between CLL
cells and their
microenvironment are
complex
Soluble factors, BCR
signaling and cell-cell
interactions are important
Chemokine receptors and
BCR-associated kinases
are current drug targets
Targeting the microenvironment in
CLL: Plerixafor (AMD3100)
Plerixafor is a CXCR4
antagonist and blocks
HIV-1 entry into T cells
 Plerixafor is a bicyclam
 Plerixafor binds to Asp171
in TM-IV and Asp262 in
TM-VI of CXCR4

From: Gerlach LE et al.,
J. Biol. Chem. 276:14153, 2001
Results: Best Confirmed
Response*
0.08
mg/kg
n=3
0.16
mg/kg
n=4
0.24
mg/kg
n=3
0.32
mg/kg
n=7
0.42
mg/kg
n=4
Overall
n=21
No. of Evaluable Patients
3
3
2
7
3
18
Evaluable patients with, n
(%):
Complete Response
Partial Response (PR)
Stable Disease (SD)
Progressive Disease
Relapsed Disease
Treatment Failure
0
2 (67)
0
1 (33)
0
0
0
0
0
3 (100)
0
0
0
0
0
2 (100)
0
0
0
4 (57)
2 (29)
1 (14)
0
0
0
2 (67)
0
0
0
1 (33)
0
8 (44)
2 (11)
7 (39)
0
1 (6)
* Responses were assessed based on definitions provided by the National Cancer Institutesponsored Working Group guidelines for chronic lymphocytic leukemia. Cheson BD, et al; Blood.
1996 Jun 15;87(12):4990-7.
Targeting of BCR signaling in CLL
•
•
•
•
From: Nat Rev Immunol 2:945
BCR-associated kinases are
targets of new drugs in
preclinical and clinical
development
SYK (Spleen tyrosine
kinase) inhibitors:
fostamatinib (R788)
BTK (Bruton’s tyrosine
kinase) inhibitors: ibrutinib
(formerly: PCI-32765)
PI3 kinases: IsoformSelective Inhibitor of PI 3Kinases, GS-110 (formerly:
CAL-101)
Mean % Change from Baseline
Pattern of Response:
Blood Lymphocytes vs Lymph Nodes
ALC
SPD
SCR(61)
1(60)
2(57)
3(52)
4(50)
5(51)
Cycle
6(47)
7(46)
8(48)
9(43)
10(38)
11(31)
12
SPD- sum of products of lymph node dimension
Inhibition of chemotaxis
Migrated cells (% of input)
CXCL12
CXCL13
*
*
+ chemokine
means of 6 patients ± SEM, *p≤0.05 compared to Medium
*
*
+ chemokine
S. Ponader et al.,
Blood 119: 1182-9, 2012
GS-1101 (CAL-101) inhibits CLL cell
chemotaxis towards CXCL12 and CXCL13
Hoellenriegel J et al.; Blood 118(13):3603-12, 09/2011
GS-1101 (CAL-101) antagonizes CLL cell migration
beneath marrow stroma cells (pseudoemperipolesis)
Hoellenriegel J et al.; Blood 118(13):3603-12, 09/2011
PCI-32765: effects on
adhesion and migration
VCAM-1
adhesion assay
Chemotaxis
assay
From: Rooij et al., Blood 119: 2590-2594, 2012
TCL1 MOUSE MODEL OF CLL
EFFECTS OF BTK INHIBITOR IBRUTINIB
Vehicle control
Control
Ibrutinib 25mg/kg/day
+ Ibrutinib
P=0.137
30
P=0.356
20
10
0
Ctrl
(n=4)
Ibrutinib (mg/kg/day)
2.5
(n=3)
25
(n=4)
1.6
P=0.028
25
(n=4)
Outliers
S. Ponader et al., Blood 119: 1182-9, 2012
Spleen weight (g)
Body weight (g)
2.5 mg/kg/d
25mg/kg/day
P=0.64
1.4
1.2
1.0
P=0.05
P=0.01
0.8
0.6
0.4
0.2
0
Ctrl
(n=4)
Ibrutinib (mg/kg/day)
2.5
(n=3)
25
(n=4)
25
(n=4)
Outliers
BCR-RELATED BIOMARKER:
CCL3, CCL4 (MIP-1α,β)
Ibrutinib trial
pre-treatment
CCL3
CCL4
pg/mL
pre-treatment
GS-1101 trial
time (days)
S. Ponader et al., Blood 119: 1182-9, 2012
Hoellenriegel J et al.; Blood 118(13):3603-12, 09/2011
Key effects of inhibitors of
BCR-associated kinases Btk, Syk, PI3Kδ
Inhibitors of BCR
signaling and
block survival and
proliferation,
 but also homing
and tissue
retention of CLL
cells
 Effects on either
pathway differ
between patients

Adapted after: Burger JA et al., Blood. 2009 Oct 15;114(16):3367-75
Summary and outlook
Chemokine receptors and adhesion molecules are
essential for tissue homing and migration of CLL
cells
 CXCR4 and BCR-associated kinases (SYK, BTK,
PI3Kδ) are targeted in clinical trials in CLL
 These therapies “mobilize” CLL cells from the
tissues into the blood
 There is promising clinical activity of these new
therapeutic approaches
