b-catenin Confers Resistance to PI3K and AKT Inhibitors and Subverts FOXO3a to Promote Metastasis in Colon Cancer

Oriol Arqués STEM CELLS and CANCER LABORATORY

Vall Hebron Institute of Onocology Barcelona, Spain

Tenbaum et al. Nat Med. 2012

INTESTINAL EPITHELIUM TUMOR

b

b b

Dsh

LRP

Wnt

Fz

TCF/LEF genes

Lef b

ON

b

b b

TCF/LEF genes

Lef b

ON

b

b

90% of CRC patients present activating mutations in Wnt pathway

b

Vitamin D

b

b b

LRP

Wnt

Dsh

Fz

TCF/LEFgenes

LEF

b

VDR genes

VDR

b

Target Genes ?

FOXO3a b

Target genes ?

? b

NICHE

CELL FATE

CANCER CELL

?

Other Ligands

LRP

?

Other Ligands

What is the role of FOXO3a/b-catenin crosstalk in colon cancer?

n = 13 22 135 14

ADENOMA

CARCINOMA

I+II III+IV LIVER

METASTASIS

0.08

0.04

0

0.06

0.02

*= 0.0177P

Time (months)0 12 24 36 48 60 72 84 96 108 120

0

20

40

60

80

100 HighLow

P = 0.0003

n = 113

Pati

en

ts s

urv

ivin

g (

%)

Nu

cle

ar

FO

XO

3a &

b-c

at

co

nte

nt

(r.

u. )

FOXO3a FOXO3a

b-cat b-cat

FOXO3a FOXO3a

b-cat b-cat

Merge Merge

Nuclear

FOXO3a & b-catenin

a b

c d

Tenbaum et al. Nat Med. 2012

b

APC -/-; K-RasV12

METASTASIS Proliferation APOPTOSIS

- NICHE

- GENETIC

LEVELS of REGULATION

HETEROGENEOUS CARCINOMA

Normal cell APC -/-

APC -/-

ADENOMA

Stress or

PI3K/AKT Inhibitors?

PROLIFERATION

NUCLEAR FOXO3a

b

NUCLEAR b-CATENIN NUCLEAR b-CATENIN

Tenbaum et al. Nat Med. 2012

b

CELL FATE

FOXO3a ON

OXIDATIVE ESTRESS

JNK

FOXO3a

RAS

GROWTH FACTORS

RTK

EGFR/PI3K/AKT INHIBITORS

PI3K

AKT

APOPTOSIS

API-2

CETUXIMAB

b

b

b b

PROLIFERATION

b

ON

WNT INHIBITORS

Axin b

CYCLE ARREST & METASTASIS

LEF

XAV-939

BKM-120

b

b

E-cadh Phalloidin

c

a

e f

Tenbaum et al. Nat Med. 2012

b

e

AP

OP

TOSI

S (%

An

nex

in V

po

siti

ve c

ells

)

Tenbaum et al. Nat Med. 2012

T4940

30

20

10

PATIENT XENOGRAFTPATIENT XENOGRAFT

0

T49 T49T49 T49

c

T6130

20

10

0

T61 T61 T61 T61

β-cat

LY-294002XAV-939

++

+--

--

API-2 --- -

+

+ +

--

-+

BKM120

+--

-

--++ --- -- -

a

Time (days) Time (days)

d

b

b

Tenbaum et al. Nat Med. 2012

CRC PATIENT

NUCLEAR b-CATENIN ANALYSIS

PI3K & AKT INHIBITORS

PI3K & AKT INHIBITORS + WNT INHIBITORS

RESISTANCE METASTASIS

RESPONSE APOPTOSIS

OR

HIGH

LOW

GENOTYPING SEQUENOM

APC CTNNB1 AXIN1

PTEN PI3KA AKT

Fundación Olga Torres

b

TCF/LEF Target genes

ER FOXO3a

b

DOX

b-cat S33Y

rtTA2

x LEF rtTA2

4OHT

b b

ER FOXO3a

FOXO Target genes

Unknown Target genes

eGFP

E-cadh b

E-cadh

b b

rtTA2

TRE

IRES EGFP

hPGK1

b-cat

FLAG S33Y

All-in-one Lentivirus: TetON-Flag-bcatS33Y-IRES-EGFP

b

VEHICLE 4OHT DOX 4OHT + DOX

DLD-1Fb-C7

APOPTOSIS

b-catenin dominant

PROLIFERATION

FOXO3a dominant

DLD1 -1Fb-C7 XENOGRAFT DLD1 -1Fb-C7 XENOGRAFT

b

Tenbaum et al. Nat Med. 2012

E-cadherin relocation

E-cadherin Phalloidin

- - 4OHT + +

E-cadh (Clone 36)

Tubulin

Snail1

DOX + + - -

E-cadh (HECD1)

- 120

- 120

- 28

- 50

VEHICLE

DOX

4OHT

4OHT+DOX

Increased cell adhesion

A

A B B

Increased cell motility

b

Tenbaum et al. Nat Med. 2012