Targeting B cell receptor signaling in cancer: preclinical and clinical advances Jan Burger Innovations in Hematology Dan Tel Aviv Hotel, Tel Aviv, Israel May 29, 2018
Targeting B cell receptor signaling in cancer: preclinical and clinical advances
Jan Burger
Innovations in Hematology
Dan Tel Aviv Hotel, Tel Aviv, Israel
May 29, 2018
Targets in the BCR signaling pathway
Burger & O’Brien Nat Rev Clin Onc 2018
VH D JH C
NN
Somatic mutations
1/51 1/27 1/6
B-Cell Diversity: IGHV
Rearrangement and Mutation
VH in chronic lymphocytic leukemia (CLL)
– U-CLL, with 98% or more sequence homology with the corresponding consensus germline sequence
– M-CLL, with less than 98% sequence homology
Su
rviv
ing
(%
)
Survival of CLL Patients With Mutated vsUnmutated IGHV
All patients (N=84) Stage-A CLL patients (n=62)
Su
rviv
ing
(%
)
0 50 100 150 200 250 3000
20
40
60
80
100
Months
P=0.0008
Months
P=0.001
0 50 100 150 200 250 3000
20
40
60
80
100
Mutated
UnmutatedUnmutated
Mutated
Hamblin TJ et al. Blood. 1999;94:1848-1854.
In CLL:
Sites of proliferation =
sites of BCR activation
CLL lymph nodes
From: Soma LA et al,
Human Pathology. 2006;37:152-159
Proliferation
centers
Burger & O’Brien Nat Rev Clin Onc 2018
Fro
m: Y
He
rish
an
ue
t a
l., B
loo
d. 2
01
1
• Pro-B cells to pre-B cells : generation of μ heavy chain by rearranging VDJ segments
• The pre-B cell receptor (pre-BCR) μ heavy chain paired with the surrogate light chain (λ5 and VpreB)
• Mature B cells express IgM and IgD
• Subsequent B cell development occurs in the secondary lymphoid organs (SLOs)
• In the germinal centre (GC), the enzyme activation- induced cytidine deaminase (AID) introduces mutations in IGHV and IGLV to diversify the Ig repertoire (somatic hypermutation)
• AID also mediates class switch recombinationto generate IgA, IgG or IgE
• Selected GC B cells give rise to memory B cells and long-lived plasma cells
• Plasma cells home to the bone marrow or reside in SLOs, where they secrete antibodies
Burger & Wiestner, NRC 2018
• Centroblasts: somatic hypermutation in the dark zone
• Centrocytes in the light zone: antigen selection and affinity maturation
• Differentiation into memory B cells or plasma cells
• CLL cells proliferate in proliferation centers, in close contact with T cells and nurselike cells
• Antigen triggers BCR signaling in CLL cells in SLO
Antigen-dependent and oncogenic BCR signaling in B cell malignancies
a) Chronic infections can lead to clonal B cell expansion. Autoantigen can stimulate polyreactive BCRs. Autonomous BCR signalling,
b) Antigen-dependent chronic active BCR signalling is increased by oncogenic mechanisms. Mutations in CD79A and CD79B contribute to the activation of BCR signalling in ABC-DLBCL.
c) Oncogenic tonic BCR signaling. In Burkitt lymphoma (BL), expression of MYC and transcription factor 3 (TCF3) cooperate to promote tonic BCR signalling; MYC upregulates the microRNAs miR-19a and miR-19b, which in turn decrease expression of the PI3K negative regulator PTEN.
Burger & Wiestner, NRC 2018
The B cell receptor signaling pathway
Burger & Wiestner, NRC 2018
IgM and IgD receptors are highly expressed in CLL
subsets
M-C
LL
U-C
LL
CD38
neg
CD38
pos
ZAP70
neg
ZAP70
pos
del13
q,tri1
2,neg
del11
q,del
17p
0
100
200
300
MF
IR
**** ns ** *
IgMIgM IgD
M-C
LL
U-C
LL
CD38
neg
CD38
pos
ZAP70
neg
ZAP70
pos
del13
q,tri1
2,neg
del11
q,del
17p
0
50
100
150
200
MF
IR
** ns *** ns
IgD
Ten Hacken E, J Immunol. 2016
IgD stimulation induces strong HS1 protein activation
anti-IgM
(minutes)
0 2 5 0 2 5
2 5 2 5100
150
200
250
300
350
HS
1 p
ho
sp
ho
ryla
tio
n
(% u
ntr
eate
d c
on
tro
l)
Minutes of anti-IgM
Minutes of anti-IgD
**
anti-IgM
(minutes)
anti-IgD
(minutes)
anti-IgD
(minutes)
P-HS1
(Y397)
HS1
IgM and IgD: upstream signaling responses
Ten Hacken E, J Immunol. 2016
IgM induces prolonged pathway activation
P-ERK
ERK
0 2 5 15 30 0 2 5 15 30
anti-IgM
(minutes)
anti-IgD
(minutes)
5 15 302 60
100
200
300
400
BCR stimulation (minutes)
ER
K p
ho
sp
ho
ryla
tio
n
(%u
ntr
ea
ted
co
ntr
ol)
* *
*
IgM
IgD
IgM and IgD: downstream signaling responses
Ten Hacken E, J Immunol. 2016
IgM signaling exclusively induces CCL3 and CCL4 secretion
an
ti-I
gM
an
ti-I
gD
0 1000 2000 3000 4000
Untreated
0.5 µg/mL
1 µg/mL
5 µg/mL
10 µg/mL
0.5 µg/mL
1 µg/mL
5 µg/mL
10 µg/mL
CCL3 (pg/mL)
0 2000 4000 6000 8000 10000
Untreated
0.5 µg/mL
1 µg/mL
5 µg/mL
10 µg/mL
0.5 µg/mL
1 µg/mL
5 µg/mL
10 µg/mL
CCL4 (pg/mL)an
ti-I
gM
an
ti-I
gD
IgM and IgD: CCL3 and CCL4 chemokine secretion
Ten Hacken E, J Immunol. 2016
IgM induces CCL3 secretion through BCL6 down-regulation
3 6 9 12 240
500
1000
1500
BCR stimulation (hours)
CC
L3
(pg
/mL
)
anti-IgM
anti-IgD
BCL6
GAPDH
anti-IgM stimulation
(hours)
0 3 6 9 12 24
Untreated
(hours)
3 6 9 12 24
3 6 9 12 24
anti-IgD stimulation
(hours)
0 3 6 9 12 24
Untreated
(hours)
BCL6
GAPDH
BCL
6
IgM and IgD: mechanism of CCL3 production
Ten Hacken E et al., J Immunol. 2016 Sep 15;197(6):2522-31
Ten Hacken E, J Immunol. 2016
Variable CCL3 protein expression in CLL lymph nodes
• In 42 cases: 24 CCL3 positive (56%) and 19 CCL3 negative (44%) cases. • Membranous staining, impression of secretion of CCL3 into the
environment• Prolymphocytes and paraimmunoblasts particularly in the proliferation
centers were positive
Hartmann EM,… & Rosenwald A. Leukemia& Lymphoma 12:1-9, 10/2015
• CCL3 positive cases (B) shows more prominent T cell infiltrates (CD3, CD4 and CD8) • CCL3 positive cases (B) have higher number of CD57 positive cells and a higher
proliferation fraction (Ki-67-pos.)
Hartmann EM,… & Rosenwald A. Leukemia& Lymphoma 12:1-9, 10/2015
Association between CCL3 and T cell densityCCL3-neg. CCL3-pos. CCL3-neg. CCL3-pos.
BCR-RELATED BIOMARKERS:CCL3, CCL4 (MIP-1α,β)
CCL3
CCL4
pg
/mL
time (days)
pre-treatment
S. Ponader et al., Blood 119: 1182-9, 2012
pre-treatment
Ibrutinib trial
Idelalisib trial
Hoellenriegel J et al.; Blood 118(13):3603-12, 09/2011
Heavy water labeling of CLL cells prior to ibrutinib therapy
MDACC
KineMed, Inc.
Feinstein Institute
Burger J JCI Insight 2017; 2(2):e89904
Heavy water labeling of CLL cells prior to ibrutinib therapy:Effects of ibrutinib on birth and death rates
• CLL cell proliferation (“birth”) rates: before ibrutinib therapy 0.39% down to 0.05% on ibrutinib
• Death rates increased from 0.18% to 1.5%
• First direct in vivo measurements of ibrutinib’s anti-leukemia activity
• Profound inhibition of CLL cell proliferation
• Promotion of high rates of CLL cell death
Burger J JCI Insight 2017; 2(2):e89904
Role of tumour-infiltrating B cells in pancreatic ductal adenocarcinoma
Burger & Wiestner, NRC 2018
Clonal evolution on ibrutinib
Ahn, Underbayev, et al Blood 2017
Mutations in BTK & PLCG2 confer BTKi resistance
From Wiestner, Haematologica 2015
Chang, ASCO 2013; Woyach, NEJM 2014; Furman, NEJM 2014
Early clonal shifts during treatment with ibrutinib
Landau DA Nature Comm 2017
Ibrutinib-resistant patients
MDACC cohortPt # Age
(yrs)/
Gender
/
Rai
stage
Prior therapy Pre-ibrutinib
FISH cytogenetics
IGHV
(M, U)
Treatment Best
response
to
ibrutinib
Time to
PD on
ibrutinib
1 59/M
Rai III
FCR del (17p),
del (13q)
ND Ibrutinib PR 983
2 36/F
Rai IV
FCR,
R+HDMP
del (11q)* U Ibrutinib +
rituximab
PR 176
3 85/F
Rai IV
R, BR, CLB,
R+HDMP
del (17p),
del (13q), trisomy
12*
U Ibrutinib PR 554
4 58/M
Rai IV
FCR, FR,
CHOP, allo-
Tx, BR,
revlimid,
ofatumuma
b
del (17p),
del (11q),
del (13q)*
U Ibrutinib PR 669
5 58/M
Rai II
FCR, F, R, B del (11q),
del (13q)
U Ibrutinib PR 392
*Complex cytogenetics pre-ibrutinib:Pt 2: 46,XX,del(2q37),del(6q21q23), add(7q36),del(11q21q25)Pt 3: 45,X,add(X)(q24), add(6p23), add(12p13), del(17p11.2), -21Pt 4: 45,XY,del(6q13q23), add(8p21), del(11q21q24), -17,-18,+mar[5]
Clonal evolution in CLL patients during
ibrutinib therapy: Patient #1
Burger, Landau …. & Wu Nature Comm 2017
Clonal evolution during ibrutinib therapy:
transdifferentiation into histiocytic sarcoma
Burger, Landau …. & Wu Nature Comm 2017
Droplet-based detection of resistance subclonesat the time of ibrutinib treatment initiation
Conclusion: our analyses support the presence of resistant sub-clones at treatment initiation, in line with theoretical predictions
Burger JA Nature Comm 2017
SUMMARY• Ibrutinib and other BCR signaling inhibitors including
idelalisib results in major clinical benefit for patients with CLL
• However, this therapy also exerts strong selective pressure, which can promote the outgrowth of resistant subclones
• Long-term toxicity and resistance development are problems with long-term use of ibrutinib (plus: high costs)
• Intermittant therapy could help addressing these issues
Thank-
you!Collaborators:• Würzburg University: A Rosenwald, E
Hartmann• CLLGRF: F Caligaris-Cappio, N
Chiorazzi, Z Estrov, N Kay• MDACC: M Keating, W Wierda, S
O’Brien, H Kantarjian, V Gandhi, A Ferrajoli, K Balakrishnan
• UCSD: T Kipps, L Rassenti• UC Irvine: D Wodarz, N Komarova• DFCI, Broad I: C Wu, D Landau
My laboratory: Mariela Sivina, Julia Hoellenriegel, Stefan Koehrer, Ekaterina Kim, Elisa ten Hacken, ShubhchintanRandhawaFunding: CPRIT, MD Anderson Moonshot,Leukemia & Lymphoma Society
Dept. of Leukemia, MDACC