PML and RARA mutations in relapsed

Acute Promyelocytic Leukemia

Licia Iaccarino

Department of Biomedicine and Prevention

University of Tor Vergata, Rome

Rome, September 25, 2017

7th INTERNATIONAL SYMPOSIUM ON

ACUTE PROMYELOCYTIC LEUKEMIA

Zhu H.H., et al, NEJM 2014

PML and RARA mutations associated to therapy-resistance in APL

•  ATRA resistance is associated to mutations in the ligand-binding domain of the

RARA moiety of PML/RARA

•  PML mutations within the B2 domain of PML/RARA confer ATO resistance

•  Mutations in PML and RARA genes have been described in up to 47% of

relapsed APL patients Goto E., et al, Blood 2011; Zhu H.H., et al, NEJM 2014; Chendamarai E., et al, Plos One 2015; Lou Y., et al, Ann Hematol 2015; Iaccarino L., et al, BJH 2016

RA

RA

RXR

Corepressors

RARE

Granulocytic differentiation Promoter clearance

PML

PML

PML NBs reformation

ATO

ATO

ATO P53 activation

Loss of

self-renewal

Jeanne M, et al., Cancer Cell 2010

ATO

PML ATO

RARA

PML PML/RARA

degradation

*

* mutations

PML mutations in APL

RARA mutations in APL

RA

RA

RXR

RARE

Granulocytic differentiation

ATRA

ATRA

PML

ATRA

RARA

PML

PML/RARA degradation

PML

PML

PML NBs reformation

P53 activation

Loss of self-renewal

Ablain J., et al, Nat Med 2014

*

** mutations

Coactivators

•  Mutations in the normal PML allele have been proposed as additional

mechanism associated with ATO resistance

PML and RARA mutations associated to therapy-resistance in APL

ATO

PML

PML

PML NBs reformation

ATO

ATO

ATO

P53 activation

Loss of self-renewal

* *

PML degradation

•  Two refractory APL cases with PML A216V mutation reported

Jeanne M., et al, Cancer Cell 2010 * mutations

Lehmann-Che et al, NEJM 2014; Iaccarino et al, BJH 2016

Iaccarino L., et al, BJH 2016

ATRA/CHT

11 months 9 months 2°relapse

* *

APL Diagnosis

12 months

Death

* **

3 months

1° relapse

ATRA/ATO CHT

* **

PML A216V

RARA R272Q

RARA T285I

PML/RARA

Mutation

PML unrearranged

*

ATRA

ATO

Chemotherapy

PML and RARA mutations associated to therapy-resistance in APL

Lehmann-Che et al, NEJM 2014; Iaccarino et al, BJH 2016

•  Mutations in the normal PML allele have been proposed as additional

mechanism associated with ATO resistance

•  Two refractory APL cases with PML A216V mutation reported

! Design a sensitive NGS assay for detection of PML and RARA

mutations predictive of treatment resistance in APL patients

!  Investigate the time of onset of the mutations

Aims of the study

firstPCR

nestedPCR

bcr3 bcr2 bcr1

PML RARA

firstPCR

nestedPCR

1 2 3 4 5 6 7 8 9

bcr3 bcr1-2 PML

1 2 3 4 5 6 2 3 4 5 6 7 8

B2 domain ligand binding domain

•  23 APL patients relapsing after ATRA-CHT (n=14) and/or ATRA-ATO (n=9)

PML/RARA mutational analysis by NGS

Coverage (mean): PML: 33886X per base

RARA: 26051X per base

•  6/23 patients (26%) had at least one mutation in PML and RARA genes

• No mutations detectable at initial diagnosis in 3 of 6 available samples

single mutation wild-type multiple mutations ATRA-CHT ATRA-ATO

Results: mutational profile of PML and RARA at relapse

#1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 #14 #15 #16 #17 #18 #19 #20 #21 #22 #23

ATRA-CHTATRA-ATOPMLRARA

B2 LBD

PML RARA

A216V (2)

A216T (1)

L224I (1)

T291A (1) T285I

(1)

C235F (1)

F286del (1)

R272Q (1)

I222_D223insE (1)

W225C (1)

S287L (1)

3% ≤ VAF ≤ 100%

B2

PML

A216V (2)

A216T (1) E224G

(1)

L220P (1)

L290V (1)

Results: location of mutations in PML and RARA

14 mutations in 6 pts

4 mutations in 2 pts

B2 LBD

PML RARA

A216V 5%

A216T 4%

T291A 21% T285I

60%

C235F 4%

R272Q 12%

I222_D223insE 6%

B2

PML

A216V 79%

A216T 6% E224G

3%

therapy-related APL with multiple relapses after ATRA-CHT and ATRA-ATO

UPN 17

B2 LBD

PML RARA

L224I 12%

B2

PML

A216V 12%

de novo APL relapsed after ATRA-ATO as first-line therapy

UPN 23

• High prevalence of PML and RARA mutations in relapsed APL

•  A sensitive method for PML and RARA mutational analysis is required

to early detect resistant clones

•  Screening of PML and RARA mutations may help to identify ATRA and/

or ATO-resistant APL patients candidates to alternative treatment

strategies

Conclusions

Tiziana Ottone Mariadomenica Divona Laura Cicconi Serena Lavorgna Valentina Alfonso Claudia Ciardi Syed Khizer Hasan Adriano Venditti Sergio Amadori William Arcese Maria Teresa Voso Francesco Lo-Coco

Roberto Cairoli, Niguarda Hospital, Milan Monica Bocchia, University of Siena

Acknowledgements

Annette Fasan

Constance Regina Bär

Torsten Haferlach