Transcript 1 - ndmctsgh.edu.tw

Deciphering and targeting EMT-mediated
cancer stemness
Muh-Hwa Yang, M.D., Ph.D.
Institute of Clinical Medicine, National Yang-Ming University
Division of Hematology-Oncology, Department of Medicine,
Taipei Veterans General Hospital
2015-08-22
Epithelial-Mesenchymal Transition (EMT)
• EMT is a biologic process that the polarized epithelial cell,
which normally interacts with basement membrane, to
undergo multiple changes that enable it to assume a
mesenchymal cell phenotype:
• enhanced migratory capacity
• Invasiveness
• elevated resistance to apoptosis
• increased production of ECM components
2
J Clin Invest 2009;119: 1438-49
EMT is defined by cellular morphology
Yang MH et al. Nat Cell Biol 2010; 12:982-992
Yang MH et al. Nat Cell Biol 2008; 10:295-305
3
EMT in the invasive front of cancer
Normal
Tumor
Invasive front
E-cadherin
vimentin
4
Yang MH et al. Nat Cell Biol 2008; 10:295-305
EMT signaling in cancer metastasis
5
Yang & Weinberg. Cell 2004; 118:277-9
EMT Generates Cells with Properties of Stem Cells
Mani et al. Cell 2008:133:704-15
1. Blocking EMT-induced cancer stem cells
expansion reverses anti-EGFR resistance
in colon cancer
7
Symmetrical vs. Asymmetrical Division in Stem Cells
• Stem cells undergo two types of division:
ACD (asymmetrical cell division): maintain tissue homeostasis
SCD (symmetrical cell division): promote tissue regeneration
Deregulation of asymmetric cell division
in cancer stem cells
• Asymmetric cell division: one
daughter stem cells and one
differentiated daughter cells,
maintain stem cell pool
• Symmetric cell division: two
daughter stem cells, expand
stem cell pool
Question: whether EMT expands CSC pool
for facilitating cancer progression?
9
Cell Stem Cell 2013;12:602-15
Enrichment colon cancer stem cells (CCSC) through tumorispheres
SDCSC: sphere-derived cancer stem cells
SDAC: sphere-derived adherent cells
Increased symmetrical division in CCSC
CE: co-expression
IE: inverse expression
miR146a is the top-ranked miRNA in two CCSC miR-seq
miR146a is segregated into the daughter stem cells
Snail is the major EMT factor for guiding symmetrical division
CE: co-expression
IE: inverse expression
Snail regulates MIR146A transcription through -catenin/TCF4 complex
miR146a represses Numb to activate Wnt pathway
Numb and cell division mode determination
•
•
•
•
A cell-fate determinant during development
Has been found to be associated with Notch1, LNX1, EPS15
Plays crucial role in asymmetrical cell division.
During cell division, Numb is asymmetrically localized in daughter cells.
The daughter cell containing Numb is able to differentiate.
• Inhibits Notch signaling through ubiquitylation of Notch
Numb interacts with -catenin to promote its polyubiquitylation & degradation
EGFR Expression in Solid Tumors
EGFR is expressed in a variety of solid tumors
Head and neck
(SCCHN)
Colorectal
Lung
(NSCLC)
Tumor Target
%
Colorectal cancer
72–89
Head and neck cancer
95–100
Lung cancer (NSCLC)
40–80
Breast cancer
14–91
Ovarian cancer
35–70
Renal cell cancer
50–90
Pancreatic cancer
30-95
Cunningham et al. N Engl J Med 2004;351:337–345; Grandis et al. Cancer 1996;78:1284–1292; Salomon et al. Crit Rev Oncol
Hematol 1995;19:183–232; Walker & Dearing. Breast Cancer Res Treat 1999;53:167–176; Folprecht et al. ASCO 2004 (Abs283).
KRAS mutation confers anti-EGFR resistance in CCSC
Crosstalk of EGFR and Wnt pathway in CCSC
Inhibiting MEK or Wnt activity of SDCSCs
reduces symmetric division and suppresses tumor growth
PD98059: MEK inhibitor
IWR: Wnt inhibitor
Snail(+)Numb(-) profile predicts cetuximab resistance & poor prognosis
of colorectal cancer patients
Yang MH*, et al. Nat Cell Biol 2014;16: 268-280
News & Views in Nat Cell Biol 2014;16: 212-214
2. Targeting Twist1-mediated signal
prevents EMT induces invasiveness
in head and neck cancer
27
The role of let-7 family microRNAs in stem cell and cancer
Cell 140, February 19, 2010
let-7 is important for stem cell differentiation
Nature Genetics , volume 41, number 7 (July ,2009 )
let-7 is critical for suppressing cancer progression
Downregulation of let-7i enhances stem-like properties
29
Twist1 represses let-7i expression
30
let-7i does not affect EMT phenotype
EMT reorganizes cytoskeleton to enable
cancer cell movement
32
Nat Rev Mol Cell Biol 2014; 15:178-96
33
Repression of let-7i promotes cellular protrusions & elongation
in 3D culture
OECM1mCherry
OECM1let7i-1
FaDuspg-ctrl
FaDuspg-let7i-1
F-actin
/DAPI
F-actin
/DAPI
34
let-7i is critical in Twist1-induced movement
through targeting the Rac1 activators NEDD9 & DOCK3
35
Repression of let-7i is critical for Twist1-induced local invasion
FaDu + control vector
FaDu + Twist1
FaDu + let7i sponge
FaDu + Twist1 + let7i
36
Yang WH, et al. Nat Cell Biol 2012; 14: 366-74
Clinical Characteristics of head and neck cancer
 Includes cancers originating from oral
cavity, oropharynx, hypopharynx, and
larynx.
 4th cause of male cancer death in Taiwan
 > 90 %: squamous cell carcinoma (HNSCC)
 Associated with smoking, drinking, betel
nut chewing
 Frequent local invasion with tissue
destruction but low incidence of distant
metastasis
Clinical significance of let-7i
in head and neck cancer patients
Invasion to adjacent tissue
Current Biology 2012
Head and neck cancer and glioma are
“invasive-predominant cancers”.
Is there any common strategy
for treating the invasive-predominant
cancers?
40
Imipramine blue halts mesenchymal migration of
head and neck cancer
41
Imipramine blue treatment reverses Twist1-induced EMT
IB inhibits NF-B activity in head and neck cancer cells
Imipramine blue promotes Twist1 degradation through FBXL14mediated polyubiquitination
4444
Imipramine blue promotes degradation of multiple EMT factors
Blocking Twist-mediated signals attenuates
EMT and local invasion
46
Yang WH., et al. (Oncogene 2015 Aug 10 online )
Acknowledgements
Institute of Clinical Medicine,
National Yang-Ming University,
Taipei, Taiwan
Wei-Lun Hwang (postdoc)
Wen-Hao Yang (previous postdoc)
Chun-Hung Chou (PhD student)
Chia-Hsin Hsieh (PhD student)
Po-Hsien Chiu (research assistant)
Hsin-Yi Lang (research assistant)
Hsiao-Jun Wang (research assistant)
Wen-Hao Hsu (research assistant)
Yun-Hsuan Su (master student)
Prof. Hsei-Wei Wang (NYMU, Taiwan)
Prof. Shyh-Kuan Tai (Taipei Veterans General
Hospital)
Prof. Jack L. Arbiser (Emory School of
Medicine, USA)