Patricia Steeg, PhD, Chief of Women's Cancers Section at the Center for Cancer Research at NCI, will present her novel research relating to metastatic breast cancer, including the development of experimental models of brain metastasis. Join SHARE and Dr. Steeg for this nformative webinar.

1. New Strategies to Prevent Breast Cancer Metastasis
Patricia S. Steeg, Ph.D.
Women’s Malignancies Branch
NCI

3. Breast Cancer Survival by Subtype, After Initial Metastatic Diagnosis
DFCI
N= 188
The Netherlands
N= 815
Br. Ca. Res. Trt. 141: 507, 2013
JNCCN 12: 71, 2014

4. Retrospective Evaluation of 199 MBC Patients (2004-2007) at DFCI
Number of Lines of Chemotherapy by Disease Subtype

5. Metastasis can be prevented:
Prevention of a first metastasis
Prevention of additional metastases in limited
metastatic setting
We will need new clinical trial designs to validate this:
Primary metastasis prevention
Secondary metastasis prevention

6. Nature 485:S58, 2012

7. Nature 485:S58, 2012

8. Metastatic Dormancy
What is it?
Can we drug it?
What trials are needed?

9. EDG2/LPA1/LPAR1
• High levels of Lysophosphatidic
acid (LPA) in the blood stream –
(approximately 0.1 to 0.5 uM)
• LPA is a potent motogen for tumor
cells.
• LPA1 (or EDG2) is a G protein-coupled
cell surface receptor for
LPA.
• Several inhibitors of LPA1 have
been described.
Mills, Nature Rev Cancer, :582-591, 2003
Liu, Cancer Cell 15:539, 2009

10. Day: 0 2 10 70
Inject Randomize Remove Autopsy
4T1 Drug Primary PK
Mfp vs. Vehicle Tumor Metastasis
PD Markers
4T1
4T1 +
Nm23-H1
Vehicle
Debio 0719
Vehicle
Experimental Outline

11. Histological Analysis of Liver and Lung Metastasis
P < 0.0001
P < 0.0001
Average Liver Metastasis
35
Average Number of Metastasis
30
25
20
15
10
5
0
Control
LPA1 Inhibitor
Nm23-M1
Average Lung Metastasis
9
8
Slide
7
Per 6
Counts 5
4
Average 3
2
1
0
1 Control
LPA1 Inhibitor
Nm23-M1

12. LPA1 Inhibition Induced Aspects of Metastatic Dormancy
P = NS
P = 0.005
Dapi
Ki67
Cell Cycle Quiescence
Primary tumor, vehicle Primary tumor, Debio 0719
Liver Metastasis, vehicle Liver metastasis, Debio 0719
JNCI 104:1306, 2012

13. Metastatic Dormancy
Asymptomatic clinical stage, well known in breast cancer, where
metastatic progression is unapparent for years-decades.
Thought to be caused by various factors including cell cycle
quiescence, lack of angiogenesis, immune responses, etc.
Factors inducing or breaking dormancy are poorly understood
Extending dormancy a clinical goal
Several metastasis suppressor genes promote metastatic dormancy

14. Hypothetical mechanisms underlying metastasis dormancy.
Zhang X H et al. Clin Cancer Res 2013;19:6389-6397
©2013 by American Association for Cancer Research

15. Doxorubicin inhibited growth of metastases but did not decrease the number of dormant cells
as measured by signal void area.
Townson J L et al. Cancer Res 2009;69:8326-8331
©2009 by American Association for Cancer Research

16. LPA1 Inhibitors are Under Clinical Development for Fibrosis
Debio 0719 not orally
bioavailable.
SAR 100842 in phase II
trial for systemic
sclerosis.
Other LPA1 inhibitors in
trials for idiopathic
pulmonary fibrosis
Nature Med. 18: 1028, 2012

17. The Fibrosis: Metastasis Connection
Cox T R et al. Cancer Res 2013;73:1721-1732

18. SAR100842, Experimental Designs
SAR100842:
LPA1, LPA3 antagonist in nm range
Orally available
In phase II trials for systemic scleroderma
Will SAR100842 induce metastatic
dormancy?
4T1 Model System:
MDA-MB-231 Model System:

19. Primary Metastasis Prevention Scenarios –
•Multiple positive lymph nodes
•Chest wall recurrences
•Post-neoadjuvant therapy
Locally Advanced Breast Cancer
Neoadjuvant therapy
pCR No pCR
FDA Guidance for Opportunity for
Drug Approval Metastasis
(Pertuzumab) Prevention ?

20. Post Neo-Adjuvant Randomized Phase II Trial to Prevent Metastasis
“Primary” Metastasis Prevention
Entry: Patients with locally advanced primary breast cancers
Undergo neoadjuvant chemotherapy
No Pathologic complete response
Randomization: +/- Metastasis Preventive
End Point: Metastasis Free Survival
Toxicity, QOL
Biopsies for molecular markers at progression

21. Brain Metastases
Why doesn’t chemo work?
Can it be prevented?
What trials are needed?

22. Possible “soils” for brain metastatic colonization:
Perivascular space
Parenchyma, altered by neuroinflammation
Leptomeninges
Steeg, Camphausen and Smith
Nat. Rev. Cancer 11: 1, 2011

23. Development of the 231-BR Brain Metastatic Model System
MDA-MB-231
Parental cells
(231P)
Brain tumor isolation;
growth in cell culture
Intracardiac
Inoculation
Re-injection of 231-Brain cell line (six
MDA 231- Brain Cell Line
(231Br)
1.
2.
3.
4.
5.
sequential rounds)
Brain Metastasis
6.
Yoneda et. al, (2001) J. Bone and Mineral Research

24. Additional Experimental Brain Metastasis Models Reflect the Heterogeneity
of the Disease
Sum190 BR3 (Her-2+, IBC) 4T1 BR5 (triple neg)
Jimt1-BR3 (Her-2+) MCF7 Her-2 BR3(ER+, Her-2+)

25. What is the role of the Blood-Tumor Barrier ?
None-
Gadolinium gets into brain metastases for imaging
Mice harboring experimental brain metastases, when
injected with Evans Blue, get blue lesions.
Uh-uh, the blood-tumor barrier is still at least partially functional-
Chemotherapy does not work in the brain

26. BRAIN SYSTEMIC
Reduced
Efflux
Transport
Inject with brain-tropic breast cancer cells, allow mets to form
Inject dyes or radiolabelled drugs into the circulation
Perfuse dyes and drugs from the circulation
At necropsy, make a single section of the brain
Image Image Image drug uptake
Metastases Marker uptake using phospho-imager
Using GFP on Red flourescent
channel
Efflux
Transport
TUMOR

27. 14
Heterogeneous Uptake of C-Paclitaxel in Brain Metastases
Metastasis 3kDa TR Dextran C- 14 Paclitaxel
Clin. Cancer Res. 16: 5664, 2010
15% = normal brain
47% increased < 10-fold;
27% increased 10-50-fold;
10% > 50-fold
Pearson r2 = 0.034

28. Concentrations of Capecitabine and its Metabolites in Craniotomy Specimens
Patient, Drug
Morikawa et al, Neuro-Oncology, In press

31. NONE of the Drugs Tested Had “Treatment” Activity in the 231-BR Model
Detectable Metastasis : Single Metastatic Cell or Micrometastasis:
Millions of tumor cells A few tumor cells
Tortuous blood supply Fairly normal blood supply
Needs to induce tumor cell Cytostatic molecular
death inhibitors could keep it dormant
Drug delivery difficult Drug delivery ok

32. Clinical Trial Designs for Brain Metastasis Patients
Progression after WBRT. Most trials. Easy to recruit.
Endpoint- lesion shrinkage
Is this different biologically from less advanced disease?
Concurrent with WBRT. The elusive radiation sensitizers
Endpoint – lesion shrinkage
Brain metastasis prevention.
Metastatic setting
Endpoint: Time until brain metastasis
Time, $$$, recruitment criteria?

33. Clinical Trial Designs for Brain Metastasis Patients
Progression after WBRT. Most trials. Easy to recruit.
Endpoint- lesion shrinkage
Is this different biologically from less advanced disease?
Concurrent with WBRT. The elusive radiation sensitizers
Endpoint – lesion shrinkage
Secondary Prevention. Prevention of additional metastases in patients with
limited brain metastases.
Endpoint: Time until a new brain metastasis
Examples: Lapatinib, Temozolomide, Pazopanib
Nature 485:S58, 2012
Brain metastasis prevention.
Metastatic setting
Endpoint: Time until brain metastasis
Time, $$$, recruitment criteria?

35. Vehicle
TMZ
TMZ
Days: 0 20 40 60 80 100 120 140

36. TMZ is Ineffective in a Brain Metastasis Treatment Scenario
Also:
TMZ prevention of brain metastasis was MGMT dependent

37. Randomized Secondary Brain Metastasis Prevention Trial
Christina Tsien, PI University of Michigan for SWOG
Enrollment: HER2+ Patients with 1-3 brain metastases,
treated with SRS or surgery, No WBRT.
At very high risk for development of additional
metastatses.
Randomize: T-DM1 as backbone systemic therapy
TMZ, metronomic dose and schedule- or none
Endpoint: Time to development of a new metastasis outside
of the SRS bed, at 3 mo.
NOT shrinkage of the existing lesion
Toxicity, QOL
Time to WBR
Status: Phase I run in under development, in collaboration
with Genentech

38. Trials of Interest: LANDSCAPE
Single arm phase 2 trial
HER2+ MBC with brain mets
no WBRT, Lapatinib, Capecitabine
Primary endpt- 50% volumetric response
in absence of increased steroid
no progressive neurological symptoms
no progressive CNS disease
Lancet Oncol. 14: 64, 2013

39. “Window of Opportunity” study
Phase II trial of Laptinib/Capecitabine in patients with
Brain metastases, locally treated
Minesh Mehta
University of Maryland
Trial under development

40. Pazopanib Preclinical Data
231-BR-HER2:
B-Raf inhibitor
No change in
vessel density
MCF7-HER2-BR3:
By MRI
Clin. Cancer Res. 17:142, 2010

41. Pazopanib Inhibits the Astrocytic Neuro-inflammatory Response
A Subpopulation of Astrocytes are Phospho-PDGFR-b+
Experimental Metastases
Human Craniotomy Specimen
Am. J. Pathol. 182:2368, 2013

42. How To Enroll Primary Brain Metastasis Prevention Trials?

44. BBrraaiinnMMeettssBBCC..oorrgg
Understanding brain metastases, available treatments,
and emerging research.
A Website for Patients and Families . . .
Musa Mayer
Helen Schiff
Lilla Romeo (deceased)

45. GEORGE SLEDGE, STANFORD
ANDY SEIDMAN, MSKCC
DAVID PEEREBOOM, CCF
RENATA DUCHNOWSKA,
JACEK JASSEM, POLAND
QUENTIN SMITH, TEXAS TECH
PAUL LOCKMAN, W VA UNIVERSITY
SWOG:
CHRISTINA TSIEN
MARK GILBERT
GABRIEL HORTOBAGYI
FUNDING:
DOD CENTER OF EXCELLENCE
NCI
BREAST CANCER STAMP FUND
NCI:
DIANE PALMIERI
BRUNILDE GRIL
STEPHAN WODITSCHKA
TIFFANY LYLE
EMILY HUA
YONG QIAN
JEAN CLAUDE MARSHALL
JOSHUA COLLINS
ADVOCATES:
MUSA MAYER
LILA ROMEO (DECEASED)
HELEN SCHIFF