Presentation by Dr. Wafik El-Deiry on June 4, 2017 entitled "Emerging Complexity of Tumor Heterogeneity and Clinical Practice" at the Tumor and Clinical Heterogeneity Education Session in the Tumor Biology Track at the 2017 ASCO meeting in Chicago.

1. Emerging Complexity of Tumor
Heterogeneity and Clinical Practice
Wafik El-Deiry, MD, PhD, FACP
Deputy Cancer Center Director for Translational Research
Co-Leader, Molecular Therapeutics Program
Fox Chase Cancer Center
Tumor and Clinical Heterogeneity Educational Session
June 4, 2017

2. Disclosures
Presented by: Wafik El-Deiry, MD, PhD, FACP
• Oncoceutics: Founder, Shareholder (no research funding)
– Clinical stage company developing ONC201/TIC10 as cancer therapeutic
– El-Deiry Lab performs basic research on cell death, TRAIL signaling and ONC201
• P53-Therapeutics: Founder, Shareholder (no research funding)
– Early stage company developing small molecules targeting mutant p53
– El-Deiry Lab performs basic research on p53 mechanisms and therapeutics
• Morphotek: Sponsored Research Funding
– Supports 3D organoid cultures as predictive assays in immune suppressive microenvironments
• Caris Life Sciences: Co-Chair National Steering Committee for Centers of Excellence Network
(no research funding)
– Precision medicine company

3. Learning Objectives
After reading and reviewing this material, the
participant should be able to:
• Appreciate clinical and molecular heterogeneity of cancer
– Focus on colorectal cancer (lessons relevant to other tumors)
• Understand complexities and issues for patient care with
tumor heterogeneity
Presented by: Wafik El-Deiry, MD, PhD, FACP

4. Presentation Outline
• Landscape of clinical and molecular heterogeneity
in colorectal cancer
• Issues in care of patients with heterogeneous
tumors and treatment responses
• Open questions in the field and future directions
Presented by: Wafik El-Deiry, MD, PhD, FACP

5. Clinical heterogeneity of CRC
• Landscape of clinical and molecular heterogeneity
in colorectal cancer
Presented by: Wafik El-Deiry, MD, PhD, FACP

6. Clinical heterogeneity of CRC
• Landscape of clinical and molecular heterogeneity
in colorectal cancer
Presented by: Wafik El-Deiry, MD, PhD, FACP
Age, Stage (I-IV), Location (right, left,
rectal), Risk (family history, IBD)
WT, KRAS/NRAS, BRAF, MSI

7. Clinical heterogeneity of CRC
• Landscape of clinical and molecular heterogeneity
in colorectal cancer
Presented by: Wafik El-Deiry, MD, PhD, FACP
Age, Stage (I-IV), Location (right, left,
rectal), Risk (family history, IBD)
WT, KRAS/NRAS, BRAF, MSI
Operable Inoperable

8. Landscape of host & tumor heterogeneity
Presented by: Wafik El-Deiry, MD, PhD, FACP
• Clinical heterogeneity
• Host heterogeneity
• drug metabolism
• Microbiome
Cellular & Molecular Heterogeneity
• Inter-patient tumor heterogeneity
• Intra-tumoral heterogeneity
• within primary tumor
• within metastases
• within a metastasis
• Intergenic heterogeneity
• TME heterogeneity; immune, stroma
• Response heterogeneity
• Tumor evolutionVogelstein etal. Science 239:1546-1558,2013

9. Clinical heterogeneity of CRC
• Landscape of clinical and molecular heterogeneity
in colorectal cancer
Presented by: Wafik El-Deiry, MD, PhD, FACP
In early stage CRC we currently do not
assess molecular heterogeneity beyond
universal testing for MMR protein
expression and genetic risk in those with
family history or early age-of-onset
disease

10. Molecular heterogeneity of CRC
• Landscape of clinical and molecular heterogeneity
in colorectal cancer
Presented by: Wafik El-Deiry, MD, PhD, FACP
• In CRC, including advanced disease,
no two tumors are exactly alike
• Drivers
• Passengers
From Volgelstein and colleagues:
Wood et al. Science 318:1108-1113,2007

11. Host heterogeneity in CRC treatment
• Landscape of clinical and molecular heterogeneity
in colorectal cancer
Presented by: Wafik El-Deiry, MD, PhD, FACP
Host heterogeneity in 5-FU
metabolism described in late 1990’s

12. • Landscape of clinical and molecular heterogeneity
in colorectal cancer
Presented by: Wafik El-Deiry, MD, PhD, FACP
PK-guided dosing of 5-FU allows for
more cycles before adverse side
effects including in early stage CRC
Kline et al., Clinical Colorectal Cancer 13:119-126, 2014
Host heterogeneity in CRC treatment

13. • Landscape of clinical and molecular heterogeneity
in colorectal cancer
Presented by: Wafik El-Deiry, MD, PhD, FACP
PK-guided dosing of 5-FU in CRC remains
as an opportunity for personalized therapy
given the large variation among
individuals in 5-FU metabolism
More work is needed for prospective
validation but it is important
Host heterogeneity in CRC treatment

14. Molecular heterogeneity of mCRC
Presented by: Wafik El-Deiry, MD, PhD, FACP
A series of well-described molecular
genetic and epigenetic changes
occur leading to colorectal cancer

15. Molecular heterogeneity of mCRC
Presented by: Wafik El-Deiry, MD, PhD, FACP
Nearly 50% of CRCs are driven by
KRAS or NRAS mutations while
~10% have BRAF mutations; the rest
are wild-type for Ras and BRAF
Louisa Lo, Timothy Price, Joanne Young and Amanda
Townsend (2016). BRAF Mutation in Colorectal Cancer,
Colorectal Cancer - From Pathogenesis to Treatment, Prof. Luis
Rodrigo (Ed.), InTech, DOI: 10.5772/62226. Available from:
https://www.intechopen.com /books/col orectal-cancer-from-
pathogenesis-to-tr eatment/br af-m utati on-i n-col or ectal-cancer

16. Molecular heterogeneity of mCRC
Presented by: Wafik El-Deiry, MD, PhD, FACP
Low intra-patient inter-
metastatic genetic
heterogeneity and genomic
complexity are associated with
favorable patient outcome
Sveen A, et al. Intra-patient Inter-metastatic
Genetic Heterogeneity in Colorectal Cancer as
a Key Determinant of Survival after Curative
Liver Resection. PLOS Genetics 12(7):
e1006225, 2016.
https://doi.org/10.1371/journal.pgen.1006225
http://journals.plos.org/plosgenetics/article?id=
10.1371/journal.pgen.1006225

17. Limited heterogeneity in treatment-naïve tumors
Presented by: Wafik El-Deiry, MD, PhD, FACP
• Passenger mutations accounted for all intra-tumoral
heterogeneity
• Genetic similarity among founding cells of metastases
was higher than expected for any two cells from a
normal tissue
• Uniformity of drivers among metastases encouraging

18. Response heterogeneity of mCRC
Presented by: Wafik El-Deiry, MD, PhD, FACP
Chemotherapy plus cetuximab is
associated with improved OS (vs
chemo alone) in (extended) WT RAS
mCRC; OS worse if mutant Ras with
combination
Van Cutsem et al., Journal of Clinical
Oncology 33:692-700, 2015
Follow-up of CRYSTAL study

19. Molecular heterogeneity of mCRC
Presented by: Wafik El-Deiry, MD, PhD, FACP
Misale et al., Cancer Discovery 4:1269-1280, 2014
• Response to anti-EGFR therapies
accompanied by selection of
preexisting resistant clones.
• Resistant clonescan emerge with
therapy
• Clones carrying distinct alterations
in KRAS, NRAS, EGFR, BRAF muta
tions or KRAS, HER2,
or MET amplifications can coexist in
the same metastaticsite or in
different metastaticsites.
Bardelli and colleagues:

20. EGFR and Ras mutations in mCRC following cetuximab
Presented by: Wafik El-Deiry, MD, PhD, FACP
Mutation in the extracellular domain of EGFR in patients who have been treated with
cetuximab: S492R is still sensitive to panitumumab. Other mutations described at
2014 ASCO include R451C and K467T. In some but not all patients, mutations
preexisted at the time of diagnosis.

21. Resistance to anti-EGFR in mCRC is heterogeneous
Presented by: Wafik El-Deiry, MD, PhD, FACP
Resistance mechanisms identified
from 116 KRAS WT PDX models:
ERBB2, MET, EGFR mutation,
FGFR1, PDGFRA, Ras pathway,
PI3K pathway
Nature 2015

22. Heterogeneous response following resistance to anti-EGFR in mCRC
Presented by: Wafik El-Deiry, MD, PhD, FACP
Russo et al., Cancer Discovery 6:147-153, 2016
• Corcoran and colleagues identified MEK1
pK57T as a resistance mechanism
• A heterogeneous response was observed to
panitumumab plus trametinib
v Serial analysis of plasma ctDNA during therapy
v Known MAP2K1 p.K57T mutation decreased
v A KRAS p.Q61H mutation emerged in plasma
v Segment 5 liver lesion biopsied after progression
and NGS detected KRAS p.Q61H seen in ctDNA
v The MAP2K1 p.K57T mutation in segment 8 was
not detected in biopsy of segment 5, suggesting
independent evolution of distinct resistance
mechanisms in these two metastatic lesions.

23. Heterogeneity of metastatic sites in CRC
Presented by: Wafik El-Deiry, MD, PhD, FACP
• Her2 overexpressed in ~4% of
lung mets (Odds ratio 2.247);
note HERACLES trial
• Based on Topo1 and ERCC1,
irinotecan preferred for
peritoneal metastases
• Anti-c-MET worth further
testing in liver mets

24. Heterogeneity of Ras mutations in CRC
Presented by: Wafik El-Deiry, MD, PhD, FACP
• A number of hotspots are
observed in various Ras genes
• More work is needed to
understand differences in
biology and implications for
therapy
ASCO 2016

25. Evolution of treatments for BRAF mutant CRC
Presented by: Wafik El-Deiry, MD, PhD, FACP
• The knowledge of
differences between BRAF-
mutant melanoma and CRC
has been evolving for
several years as has the
progress for therapy of
BRAF-mutant mCRC
• Data from 2015 ASCO

26. Not all BRAF mutations are the same in mCRC
Presented by: Wafik El-Deiry, MD, PhD, FACP
How should they be treated?

27. There is immune heterogeneity in CRC and
variability in tumor mutation burden
Presented by: Wafik El-Deiry, MD, PhD, FACP
• MMR-deficient CRCs have immune infiltrates and
can respond to immune checkpoint therapy; these
tumors have a high mutation burden
• Non-MMR-deficient tumors do not generally
respond to single agent immune checkpoint
therapeutics; these tumors typically do not have a
high mutation burden

28. Potentially actionable mutations in MMR-deficient CRC
Presented by: Wafik El-Deiry, MD, PhD, FACP
• Of 1104 profiled CRCs from a 2nd cohort (COSMIC), MSH2/MLH1-mutant CRCs showed higher
mutation rates in BRCA2 vs non-MMR-deficient tumors (38% vs 6%, P < 0.0000001)
• Some BRCA2 mutations predicted to disrupt interactions with partner proteins DSS1 & RAD51
• EGFR was mutated in 45.5% of MSH2/MLH1-mutant vs 6.5% of non-MMR-deficient tumors (P
< 0.0000001). 15% of EGFR mutations found maybe actionable including N700D, G719D,
T725M, T790M,and E884K
• NTRK gene mutations identified in MSH2/MLH1-mutant CRC including NTRK1 I699V, NTRK2
P716S, and NTRK3 R745L
What to do beyond
resistance to
immunotherapy; need trials
based on the new insights

29. Treatment options based on molecular heterogeneity in mCRC
Presented by: Wafik El-Deiry, MD, PhD, FACP
First-line therapy:
• Unknown status: FOLFOX, FOLFIRI, or FOLFOXIRI plus bevacizumab
• KRAS/NRAS WT: FOLFIRI (or FOLFOX) plus cetuximab
Second-line therapy:
• KRAS/NRAS WT: FOLFIRI + cetuximab (following FOLFOX + bevacizumab)
• KRAS/NRAS mutant: FOLFIRI + bevacizumab (following FOLFOX plus
bevacizumab in first-line setting)
Therapy for refractory disease:
• V600E BRAF mutant: Vemurafenib + irinotecan + cetuximab or dabrafenib
+ trametinib + panitumumab (not all BRAF mutants are the same); not yet
approved by FDA
• MSI: Immune checkpoint therapy (e.g. pembrolizumab)
• FOLFIRI + zaltrap, regorafenib, lonsurf, clinical trial, genomic profiling

30. There are many open questions regarding
managing heterogeneous colorectal tumors
Presented by: Wafik El-Deiry, MD, PhD, FACP
• When and how often to do extensive tumor profiling (and using
what platform), and will it help the patient
• How to better predict relapse or resistance
• Liquid biopsy versus tumor tissue biopsy
• What to do with multiple actionable targets
• How to combine immune checkpoint therapy & targeted agents
• How to manage mixed responses
• How to overcome therapy resistance
• How to manage heterogeneous resistance mechanisms

31. Summary
• Molecular heterogeneity and tumor evolution
present a challenge to effective colorectal cancer
therapy
• Knowledge is rapidly evolving to allow precise
therapies and algorithms for molecular subtypes
• More work is needed to unravel resistance
mechanisms, to monitor tumor evolution, and to
target therapy escape mechanisms
Presented by: