Cancer cells are addicted to
inhibitors of apoptosis
Jean-Pierre Abastado
Institut de Recherches Internationales Servier
1
Disclaimer
 I am full-time employee of ‘Servier Research Group’,
a French Research—based group dedicated to
healthcare with research & clinical-stage programs in
oncology.
2
Outlines
 Rationale for targeting inhibitors of apoptosis
 Clinical development of inducers of apoptosis
3
Outlines
 Rationale for targeting inhibitors of apoptosis
 Clinical development of inducers of apoptosis
4
Resistance to apoptosis:
hallmark of cancer
5
Resistance to apoptosis
 Hallmark of cancer
 Sensitization to:
– Mitosis inhibiting agents
– Oncogene inhibition (EGFR, RAF, MEK..)
– Chemotherapy
 Common mechanism of drug resistance
– Cancer stem cells and resistance to chemotherapy
6
Mitochondrial apoptosis is controlled by
the Bcl-2 protein family
Death cues
DNA Damage
Death receptors
Oncogenic stress
Cytoskeleton damage
NOXA
PUMA
tBID
BIM
BAD
PRO-APOPTOTIC
ANTI-APOPTOTIC
EXECUTOR
MOMP Permeabilization
7
Resistance to apoptosis:
a hallmark of cancer
 Bcl-2: at the t(14;18) translocation breakpoint in FL
- Overexpression (translocation, amplification, loss of miRNA,
transcriptional activation …) in CLL, NHL, SCLC, luminal BC, ProCa
 Mcl-1: induced by TPA in ML-1 cells
– overexpression in AML, MCL, DLBCL, NHL, MM
8
Bcl2l1 is frequently amplified in cancer
Copy-number profiles among 50 tumors of various lineages (shown across the top) with focal
amplification of BCL-XL (Bcl2L1) are displayed for the region around BCL2L1
Beroukhim et al.; Nature, 2010
9
Oncogene activation induces
apoptosis or transformation
Oncogene
Bcl-2 family
members
Apoptosis
Oncogene
Bcl-2 family
members
Transformation
Apoptosis
Transformation
10
Oncogene addiction
11
Resistance to oncogene inhibition
MEKi=selumitinib
Corcoran et al. Cancer Cell 2013
12
Combined Bcl-XL and MEK inhibition:
synthetic lethality
Corcoran et al. Cancer Cell 2013
HCT116 CRC KRASmt
Colland et al. Unpublished
LTI8: Bcl-XL-specific inhibitor
Pimasertib MEK1/2 inhibitor
13
Synthetic lethality of BRAF and
Bcl-XL inhibition
300nM
100nM
30nM
10nM
LTI8
300nM
100nM
30nM
LTI8
10nM
DMSO
Cleaved caspase-3 COLO205 treated in
association with PLX-4032 6h + cpd 16h
PLX-4032 1µM
PLX-4032 1µM +
P-ERK
Bim
PARP
Actin
LTI8
LTI8
+ PLX-4032
PLX-4032 = vemurafenib
COLO205: CRC BRAFV600E
Colland et al. Unpublished
14
Synergy with Mitosis Inhibiting
Agents
Mcl-1 degradation
Cell vulnerability
to apoptosis
15
Synergy with mitosis inhibiting
agents
Taxol
Mitotic arrest
Mcl-1 ubiquitination
Mcl-1 degradation
Bcl-XL dependancy
Wertz et al Nature 2011
16
Role of Bcl-xL in resistance
to taxol in ovarian cancer
Paclitaxel (nM)
Clinical response to Taxanes
Bcl-xL expression (IHC)
ABT-263
Synergy between Taxol and ABT-263
Poor
responders
Responders
Wong et al Mol. Cancer Ther 2012
17
Synergy between Taxol and
Bcl-xL inhition
Caspase 3 activation
PARP
BclXL
Mcl-1
Bax
+Taxol
HCT116
Actin
Colland et al. Unpublished
18
Bcl-2-mediated chemoresistance
of HCC Cancer Stem Cells
Ma et al. Oncogene 2008
19
Bcl-xL- mediated chemoresistance of colon CSC
Growth of spheroid cultures
Caspase activation in
spheroid cultures
Oxaliplatin
ABT-199 (Bcl-2i) + Oxaliplatin
ABT-737 (Bcl-2i/Bcl-xLi) + Oxaliplatin
WEHI-539 (Bcl-xLi) + Oxaliplatin
Colak et al. CDD 2014
20
 Rationale for targeting inhibitors of apoptosis
 Clinical development of inducers of apoptosis
21
The Bcl-2 proteins are essential for the development
and homeostasis of the hematopoietic system
Brinkmann et al CDD 2014
22
Multi-specific inhibitors
 AT-101 (Gossypol pro-drug)*-> pan-Bcl-2. Heme tox
 Obatoclax*: pan-Bcl-2-> Limited activity in Hodgkin’s
lymphoma
 ABT-737: Bcl-xL, Bcl-2 and Bcl-w -> poor ADME
 ABT-263 (Navitoclax): Bcl-xL, Bcl-2 and Bcl-w -> activity in
CLL but thrombocytopenia
* Induce apoptosis in BAX/BAK deficient cells (Vogler et al CDD 2009)
24
Bcl-2-specific inhibitors
Company
Drug
Target
Comments
Phase
Indication
Genta
Genasense
(Oblimersen)
Antisense oligo
targeting Bcl-2
Various combinations
Failure and bankruptcy
Ph 3
AML, CLL,
MM, Mel,
NSCLC
AbbVie
Genentech
ABT-199
(Venetoclax)
Bcl-2
+RTX vs Benda + RTX
Ph 3
CLL
Servier
Novartis
S 55746
Bcl-2
monotherapy
+ RTX
+ Obituzumab
+RTX and Bendamustine
+ R-CHOP ou Obi-CHOP
CLL, NHL
Ph 1
Ph 1b
Ph 1b
Ph 1b
monotherapy
+ Decitabine or Aza
+ Cytarabine
Ph 2
Ph 1
Ph 1/2
AML
monotherapy
+ Bortezomid and Dexamethasone
Ph 1
Ph 1b
MM
monotherapy
Ph 1
CLL, NHL
AML, MDS
25
BCL-2-selective S55746 induces
apoptosis with no platelet toxicity
Apoptosis induction in RS4;11
leukemia xenograft model
Platelet count
(16 hours post
Per Os treatment)
(16 hours post Per Os treatment
DEVDase/Caspase-3 activities in tumour lysates,)
1400
1200
Platelets (x103/µl)
10000
8000
6000
4000
1000
800
600
400
2000
200
ABT-263
100 mg/kg
S 55746
100 mg/kg
Vehicle
0
Untreated
ABT-263
100 mg/kg
S 55746
100 mg/kg
S 55746
25 mg/kg
1
Vehicle
0
Untreated
DEVDase activity (RFUs)
12000
Geneste et al. Unpublished
26
Activity of S 55746 in ALL model
Leukemia xenograft model (RS4;11) per os administration:
RS 4;11 MTT IC50 = 61 nM
2500
2250
Tumour weight (mg)
Median +/- IQR
2000
1750
1500
1250
Dosing
1000
750
Control (untreated)
500
12.5 mg/kg
25 mg/kg
250
50 mg/kg
0
100 mg/kg
0
5
10
15
20
25
30
35
40
45
50
55
Time after treatment initiation (days)
Geneste et al. Unpublished
27
Ongoing clinical studies w S55746
 Phase I dose-escalation study of oral administration
of the selective Bcl-2 inhibitor S 55746 in patients
with refractory or relapsed Chronic Lymphocytic
Leukemia and B-Cell Non-Hodgkin Lymphoma
 Phase I dose-escalation study of the orally
administrated selective Bcl-2 inhibitor S 55746 as
monotherapy for the treatment of patients with
Acute Myeloid Leukemia (AML) or high or very high
risk Myelodysplastic Syndrome (MDS)
28
Mcl-1 is frequently amplified in
human cancers
Most frequently amplified
Targeted therapies
Beroukhim et al. Nature (2009)
29
BH3 mimetics activity in AML
cell lines
Activity on AML cell lines:
Cell line
IC50 (M)
HL-60
5.25E-08
KG-1
7.65E-08
MOLM-13
2.00E-09
NOMO-1
5.00E-09
OCI-AML2
5.95E-08
PL-21
4.40E-08
THP-1
9.00E-09
MV4;11
1.37E-09
Activity in primary AML:
S-Mcl1-i2
S-Mcl1-i1
Control
Wei et al. Unpublished
30
Mcl-1 inhibition in primary AML
S-Mcl1-i1
Wei et al. Unpublished
31
In vivo activity in xenograft models
MM model: AMO-1
AML model: MV4;11
3000
2800
2600
2400
3
T u m o u r v o lu m e s (m m )
2200
00
00
00
00
00
00
00
00
00
2000
M e d ia n + /- IQ R
00
1800
1600
1400
1200
1000
800
T r e a tm e n t Q 1 D x 5
600
S 6 4 3 1 5 - 1 3 . 1 2 5 m g /k g IV Q D 5
400
S 6 4 3 1 5 - 1 6 .2 5 m g / k g IV Q D 5
200
S 6 4 3 1 5 - 1 1 2 .5 m g / k g IV Q D 5
0
C o n tr o l ( u n tr e a te d )
0
4
8
12
16
20
24
28
32
36
40
44
48
52
56
60
64
D a y s a fte r tr e a tm e n t in itia tio n ( D a y s )
00
T r e a tm e n t Q 1 D x 5
00
T r e a tm e n t Q 1 D x 5
00
S 6 4 3 1 5 - 1 3 . 1 2 5 m g /k g IV Q D 5 S 6 4 3 1 5 - 1 3 . 1 2 5 m g /k g IV Q D 5
00
S 6 4 3 1 5 - 1 6 .2 5 m g / k g IV Q D 5
S 6 4 3 1 5 - 1 6 .2 5 m g / k g IV Q D 5
S 6 4 3 1 5 - 1 1 2 .5 m g / k g IV Q D 5
S 6 4 3 1 5 - 1 1 2 .5 m g / k g IV Q D 5
S-Mcl1-i1
00
Control
0
C o n tr o l ( u n tr e a te d )
C o n tr o l ( u n tr e a te d )
2 0 0 2 4 4 2 8 8 3 21 2 3 61 6 4 02 0 4 42 4 4 82 8 5 23 2 5 63 6 6 04 0 6 44 4
48
D a y s a fte r tr e a tm e n t in itia D
tioany s( Da afte
y sr )tr e a tm e n t in itia tio n ( D a y s )
52
56
60
Geneste et al. Unpublished
64
32
Synergy between Mcl-1 and
MEK inhibition
Untreated
S-Mcl1-i1
MEK1/2i
Combination
Geneste et al. Unpublished
33
Synergy between BCL-xL/Mcl1 inhibition
S-Mcl1-i
LT18
+
S-Mcl1-i
NSCLC
Colland et al. Unpublished
34
Conclusions
 The balance between pro- and anti-apoptotic Bcl-2
family proteins is altered in many cancers
 Strong rationale to inhibit anti-apoptotic proteins
 Need for highly specific drugs with good ADME
properties
 Combinations with chemo- or targeted therapies
35
Acknowledgments
Servier
Director
Project Leaders
Chemistry
John Hickman
Olivier Geneste
Frédéric Colland
Andras Kotschy
Zoltan Szlavik
Jerôme Starck
Arnaud Le Tiran
Ana Leticia Maragno
Gaëtane Le Toumelin
Ghislaine Guasconi
In vitro Pharmacology
Marion Zarka
Aurélie Studeny
Vincent Lemesre
In vivo Pharmacology
Alain Bruno
Maïa Chanrion
Gaelle Lysiak
Emilie Schneider
Anne Marie Girard
Vernalis
Biophysics and Structural Sciences James Murray
Structure Guided Med. Chem.
James Davidson
Modelling
Ijen Chen
The Alfred Hospital
Monash Univ
Project leader
Andrew Wei
Donia Moujalled
Tse-Chieh Teh
36
Triple inhibition of MEK, PI3K and
Bcl-XL in NSCLC cells
MEK + Bcl-XL
MEK + Bcl-XL + PI3K
Tan et al. MCT 2013
37
Oncogene activation induces
apoptosis or transformation
Oncogene
Bcl-2 family
members
Apoptosis
Oncogene
Bcl-2 family
members
Transformation
Apoptosis
Transformation
38