FUTURE TREATMENT OF NSCLC PATIENTS WITH NEW EGFR … · 2018. 2. 15. · 3! ABSTRACT&...

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FUTURE TREATMENT OF NSCLC PATIENTS WITH NEW EGFR TARGETING DRUGS Avoidance of EGFRTKI resistance through inhibition of CMET and the use of new generation EGFRTKI’s Mutated EGFR kinase complex in association with gefitinib(Michalczyk et al. 2008). Student: S. de Waard Supervisor: Prof. dr. F.A.E. Kruyt, Department of Medical Oncology, UMCG Date: 2006201

Transcript of FUTURE TREATMENT OF NSCLC PATIENTS WITH NEW EGFR … · 2018. 2. 15. · 3! ABSTRACT&...

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FUTURE  TREATMENT  OF  NSCLC  PATIENTS  WITH  NEW  EGFR  TARGETING  DRUGS  

Avoidance  of  EGFR-­‐TKI  resistance  through  inhibition  of  C-­‐MET  and  the  use  of  new  generation  EGFR-­‐TKI’s  

                 

                                       Mutated  EGFR  kinase  complex  in  association  with  gefitinib(Michalczyk  et  al.  2008).  

           Student:  S.    de  Waard  Supervisor:  Prof.  dr.  F.A.E.  Kruyt,  Department  of  Medical  Oncology,  UMCG                                                                                                                                                                                                    Date:  20-­‐06-­‐201  

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TABLE OF CONTENT        ABSTRACT  ........................................................................................................................................................  3    INTRODUCTION  ..............................................................................................................................................  3    NSCLC  IN  RELATION  WITH  EGFR  ..............................................................................................................  3    HOW  DID  THEY  TREAT  NSCLC  IN  THE  PAST?  .......................................................................................  4    RESISTANCE  OF  EGFR-­‐TKIS  ........................................................................................................................  5    ALK/ROS1-­‐RECEPTOR  ..................................................................................................................................  6    DIAGNOSTICS  OF  NSCLC  ...............................................................................................................................  6    EGFR-­‐TKI  RESISCTANC:  NEW  APPROACH  ..............................................................................................  7    PROTO-­‐ONCOGENE  TYROSINE  KINASE:  SRC  .........................................................................................  8    EFFICACY  OF  THE  DUAL  TREATMENT  OF  NEW  GENERATION  EGFR-­‐TKI  AND  CRIZOTINIB..8    TOXICITY  ...........................................................................................................................................................  8    DISCUSSION    ...................................................................................................................................................  12    REFERENCES  ..................................................................................................................................................  10                        

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ABSTRACT  The   treatment   of   non-­‐small   cell   lung   carcinoma   (NSCLC)   patients   with   epidermal   growth   factor  receptor   tyrosine  kinase   inhibitors   (EGFR-­‐TKI’s),   such  as  gefitinib  and  erlotinib,  was  proven  to  be  effective   in   a   subset   of   patients   with   a   mutated   constitutive   active   EGFR.   However,   during  treatment  the  cancer  cells  evolve  and  develop  resistance  against  these  EGFR-­‐TKI’s,  causing  a  major  hurdle  for  successful  treatment.  A  number  of  mechanisms  were  identified  responsible  for  this  type  of   EGFR-­‐TKI   resistance;   the  most   common  are   the   gatekeeper   EGFR-­‐T790M  mutation   and  C-­‐Met  amplification.   Some   patients   have   NSCLC   due   to   a   ROS1   or   anaplastic   lymphoma   kinase   (ALK)  chromosomal  rearrangement  while  they  have  the  same  pathology.  The  most  efficient  methods  for  this  identification  are  fluorescent  in  situ  hybridization’  (FISH)  and  immuno-­‐  histochemistry  (IHC).  To  overcome   resistance,   new   drugs   like   crizotinib   were   used   to   target   the   C-­‐Met   receptor.  Furthermore  new  generation  EGFR-­‐TKI’s  including  afatinib  and  WZ4002,  have  been  developed.  The  efficacy  of   these  new  drugs  was  tested   in  different   type  of  NSCLC  cells,   in  various   in  vitro  and   in  vivo  models.  The  combination  of  WZ4002  with  crizotinib  showed  the  most  dramatic  effect  against  the  mutated  cells,  while  the  side  effects  and  toxicity  were  marginal  compared  to  the  afatinib  and  crizotinib  combination.  Thus,  the  use  of  crizotinib  and  WZ4002  can  overcome  EGFR-­‐TKI  resistance    the  case  of  a  mutated  EGFR.      INTRODUCTION  Lung  cancer   is   the  most   lethal   form  of  cancer  throughout   the   world,   28%   of   the   male   and  26%   of   all   woman   cancer   deaths   are   due   to  lung  cancer   (Siegel  et  al.   2014).  85%  of   these  patients  have  NSCLC.  Often  these  patients  are  non-­‐smokers,  while  other  types  of  lung  cancer  like   small   cell   lung   carcinoma   (SCLC)   are  usually   more   correlated   with   smoking  (Selinger  et  al.  2013).  NSCLC  is  a  large  group  of  epithelial   lung   cancer   types   like   large   cell  carcinoma,   adenocarcinoma   and   squamous  cell   carcinoma.   Histologically   these   cancer  types   have   larger   cells   compared   to   SCLC.  Unfortunately,   NSCLC   is   quite   insensitive   to  chemotherapy   and   this   type   of   cancer   easily  metastasizes   throughout   the   body.   Patients  without  a  metastasis   are  usually   treated  with  surgery   and   radiation.   Although   NSCLC   is  insensitive   for   chemo-­‐therapy   the  old   fashion  way   to   treat   this   type   of   cancer   was   with  conventional  cytotoxic  chemicals,  especially   if  the   tumor   metastasizes.   These   chemicals  induce  DNA  damage,   inhibit  DNA  synthesis  or  the   uptake   of   nutrients   and   therefore  proliferation.   Since   these   processes   are  obviously   essential   to   all   dividing   cells   in   the  body,  these  drugs  generally  cause  severe  side  effects  (Ciarimboli  2014).  Even  if  this  approach  is  combined  with  surgery  and  radiation,  it  is  in  most   cases   not   enough   to   eradicate   the  disease  (Zhang  et  al.  2007).  This  is  why  there  is  a   lot   of   research   nowadays   to   identify   and  

develop   alternative   drugs   to   effectively   treat  NSCLC   patients.   Because   the   tumor   is   often  depending   on   specific   pathways   that   drive  proliferation,   these   drugs   are   targeted   on  specific   components   of   those   pathways.   The  RAS  and  Akt  pathways  for  instance,  which  can  be  activated  with  the  EGFR,  can  lead  to  NSCLC  pathology   (Figure   1).   In   the   case   of   EGFR  related   NSCLC   a   new   approach   is   used   to  effectively   inhibit   the   receptor   with   either  antibodies   or   tyrosine   kinase   inhibitors   (TKI),  this   essay   will   primarily   focus   on   the   latter  one.   One   of   those   drugs   are   first   generation  EGFR-­‐TKI’s   like   gefitinib   and   erlotinib.  Although   these  drugs  work  quite  well   against  NSCLC,   resistance   is   becoming   a   major  problem.   So   the  main   question   of   this   thesis  is:  What   is   the   cause   of   EGFR-­‐TKI   resistance    and  how  can  it  be  prevented?  

NSCLC  IN  RELATION  WITH  EGFR  About   15%   of   the   Caucasian   and   30-­‐60%   of  the   Asian   NSCLC   patients   have   a  mutation   in  the  EGFR  (Selinger  et  al.  2013).  The  EGFR   is  a  member   of   the   ErbB   cell   surface   receptors,  which  are  all  receptor  tyrosine  kinases  (RTKs).  In  1959  researchers  tried  to  find  an  oncogene  that   causes   neuroblastoma,   this   gene   was  identified   as  neu   (Schechter   et   al.   1984).   The  neu  oncogene  is  homological  comparable  to  v-­‐erbB,   this   is   a   viral   oncogene   which   can   be  

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isolated   from   an   erythroblastosis   retrovirus,  this   virus   actually   encodes   a   fragment   of   the  chicken   EGFR.   If   a   bird   is   infected   with   this  virus,   it   can   cause   cancer   (Schechter   et   al.  1984).   Because   of   this   phenomenon   the  researchers   thought   that   a   mutated   EGFR  could   cause   cancer.   Later   in   1965   Cohen   and  colleagues   discovered   the   epidermal   growth  factor  (EGF)  and  the  role  of  its  receptor,  which  is   to   activate   gene   transcription   and   control  the  cell  cycle  progression  (Cohen  1965).    

 Figure  1:  Downstream  signaling  pathways  in  NSCLC.  This   picture   summarizes   the   most   important   signaling  pathways   leading   to   NSCLC.   This   picture   was   modified  from    (Janku,  Stewart  &  Kurzrock  2010).    The   EGFR   receptor   consist   of   an   intra-­‐   and  extracellular   domain;   the   active   receptor   can  communicate   through   complex   pathways   in  the   cytoplasm.   The   EGFR   and   other   ErbB  receptors   can   form   dimers,   this   is   a   state   in  which   the   receptor   is   normally   active   (Zhang  et  al.  2007).  The  dimerization  process  requires  a   ligand-­‐receptor   interaction,   after   the  dimerization   the   intrinsic   protein-­‐tyrosine  kinase   domain   of   the   receptor   is   stimulated.  Because  of  this  ATP  can  bind  the  lysine  residue  of   the   tyrosine   kinase   domain   and   therefore  provides   an   organic   phosphate   group.   This   is  followed   by   an   auto   phosphorylation   process  of   several   other   tyrosine   kinase   domains   on  the   intracellular   part   of   the   receptor.   This  process   will   induce   the   RAS,   AKT   and   other    transduction   pathways   (see   also   Figure   1)  (Dawson   et   al.   2005).   The   above-­‐mentioned  pathways   are   responsible   for   several   key  regulatory   cell   processes,   for   instance  angiogenesis,   inhibition   of   apoptosis,   cell  proliferation   and   migration/invasion  

properties  (Oda  et  al.  2005).    Most  of  the  time  the  mutations   in   the   EGFR   of  NSCLC   patients  are   heterozygous,   furthermore   the   mutant  allele   can   be   overexpressed   because   of   gene  amplification.  The  EGFR  L858R  point  mutation  in   exon   21   and   the   deletion   of   exon   19   are  both   in   the   intracellular   catalytic   domain   of  the   EGFR   receptor.   These   mutations   are   the  most  common  and  can  cause  activation  of  the  receptor  (Soh  et  al.  2009).  

HOW  DID  THEY  TREAT  NSCLC  IN  THE  PAST?  The   way   NSCLC   patients   are   treated   is  depending   on   the   tumor   stage   and   patient  condition.   Stage   I,   II   and   IIIA   patients   are  treated   with   radiation,   cytotoxic  chemotherapy   and   surgery   (Bulzebruck   et   al.  1992).  Unfortunately   this   approach   is   in   a   lot  of  cases  not  enough  to  eradicate  the  tumor  in  advanced   NSCLC.   Small   molecule   EGFR-­‐TKI’s  like  erlotinib  (Tarceva®)  and  gefitinib  (Iressa®)  are   common   drugs   for   patients   with   a  mutated   overactive   EGFR.   These   drugs   can  compete  with  ATP  for  the  binding  sites  on  the  tyrosine  kinase  domain  of  the  receptor  (Figure  2A).   As   a   consequence   the   phosphorylation  and   activation   of   the   downstream   signaling  pathways  of  the  EGFR  are  disrupted.  A  double-­‐blinded   phase   III   trial   experiment   between   a  placebo   and   both   erlotinib   and   gefitinib  proved  that  these  drugs  have  a  positive  effect  on  the  survival  of  Asian  and  Caucasian  NSCLC  patients,   because   these   groups   of   patients  usually  have  the  proper  EGFR  mutation  (Chang  et   al.   2006,   Sheikh,   Chambers   2013).  Moreover,   compared   to   classical   cisplatin-­‐based   chemotherapy   both   drugs   have   a  significant   higher   efficacy,   an   extended  progression   free   survival   (PFS)   from   8.4   to  13.1  months  and  a  better  quality  of  life  (Zhou  et   al.   2011).   These   two   drugs   are   most  commonly  used  in  the  case  of  the  L858R  point  mutation  in  exon  21  or  the  deletion  of  exon  19.  Despite   the   fact   that   these  drugs   seem   to  be  quite   effective,   only   a   selected   group   of  patients  have  high  response  rates.  

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 Figure  2:  Mechanism  of  EGFR-­‐TKI  resistance.  Figure  A  shows  a  computer  simulation  of  the  crystallo-­‐  graphically  determined  binding  of  erlotinib  to  the  EGFR.  Figure  B  shows  the  steric  hindrance  due  to  the  bulkier  methionine  residue  (orange)  caused  by  the  T790M  mutation.  In  figure  C  the  steric  hindrance  of  gefitinib  and  the  T790M  mutated  EGFR  is  shown,  figure  D  shows  a  the  steric  hindrance  of  an  irreversible  EGFR-­‐TKI  with  the  mutated  EGFR  (Kobayashi  et  al.  2005).    

This   is   for   instance   the  case  with  East  Asians,  non-­‐smokers  and  female  patients.  In  a  normal  population   the   response   rate   is   just   about  10%.   Additionally,   studies   have   shown   that  there   are   many   other   important   factors   that  can   influence   EGFR-­‐TKI’s   sensitivity   (Fukuoka  et  al.  2003,  Miller  et  al.  2004).    

 RESISTANCE  OF  EGFR-­‐TKIs  EGFR-­‐TKI   Resistance   is   a   major   problem   for  NSCLC   patients.   If   some   pathways   are  inhibited  by  a  drug,  other  pathways  can  simply  take   it   over.   There   are   several   important  mutations   for   an   NSCLC   cell   to   develop  resistance   for   EGFR-­‐TKI’s.   The  most   common  is  the  T790M  mutation,  this  mutation  replaces  threonine  residue  at  location  790  with  a  bulky  methionine   residue   (T790M).   Because   of   this  substitution,   the   EGFR-­‐tyrosine   kinase   pocket  has   higher   affinity   for   ATP,   resulting   in   a  decreased   affinity   for   erlotinib   and   gefitinib  (Figure  2B,  2C).  The  T790M  mutation  occurs  in  half   of   the   tumors   that   were   treated   with  EGFR-­‐TKI’s,   the   mutation   is   usually   already  present  without  EGFR-­‐TKI  treatment,  only  the  cells   with   the   mutation   survive   because   of  clonal   selection.   However,   some   studies  

suggest  this  mutation  can  originate  because  of  the   treatment   (Kobayashi   et   al.   2005).   To  come  up  with  a  solution  researchers  came  up  with   irreversible   EGFR-­‐TKI’s,   these   small  molecules   can   bind   covalently   to   a   cysteine  residue   of   the   EGFR-­‐tyrosine   kinase   pocket.  Unfortunately   most   irreversible   EGFR-­‐TKI’s  have  many   severe   side   effects   like   skin   rash,  stomatitis,   nail   loss   and   diarrhea.   Afatinib  (Giotrif®)   is   the   most   promising   irreversible  EGFR-­‐TKI’s   while   the   side   effects   are   less  compared   to   other   experimental   irreversible  EGFR-­‐TKI’s  which  seem  to  be  less  specific  and  influence   other   tyrosine   kinase   receptors   as  well    (Tao  et  al.  2014).        

   Figure   3:   The   loss   of   tumor   suppressor   gene   PTEN.  Figure   A   demonstrates   the   continuously   activated  PI3K/Akt   pathway,   which   leads   to   Cell   survival.   EGFR-­‐TKI’s  are  able  to   inhibit  the  receptor  and  as  a  result  the  PI3P/Akt  pathway  (Figure  B).  C  shows  loss  of  PTEN:  PIP3  levels  stay  elevated  which  promotes  the  activation  of  the  PI3K/Akt  pathway.  This  mechanism  can  cause  EGFR-­‐TKI’s  resistance  (Yamamoto  et  al.  2010).    Secondly,   the   resistance   against   first   and  second   generation   EGFR-­‐TKI’s   can   be  bypassed   because   of   c-­‐Met   (MET)  amplification,   both   the   MET   and   EGF-­‐

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receptors   play   an   important   role   in   the  activation   of   the   RAS-­‐Erk1/2   pathway.  Hepatocyte   growth   factor   (HGF)   is   the   ligand  of   MET   and   it   can   activate   the   receptor  through   an   adaptor   protein   (Gab1).   This  triggers  resistance  to  reversible  EGFR-­‐TKI’s  like  erlotinib   and   irreversible   EGFR-­‐TKI’s   like  afatinib.   Because   the   EGFR   downstream  signaling   pathway   is   bypassed   through   the  MET  pathway  (Turke  et  al.  2010,  Yamada  et  al.  2010,   Yano   et   al.   2008).   In   a   Japanese   study  with   mutant   EGFR   patient’s   researchers  observed  that  HGF  was  overexpressed  in  61%  of   the   tumors   with   acquired   resistance.   This  indicates   that   HGF   can   be   a   useful   target   in  combination   with   EGFR-­‐TKI’s   to   prevent  resistance  (Yano  et  al.  2011).  

Thirdly,   activation   AKT   downstream  pathway  is  possible  because  of  the  loss  of  the  tumor   suppressor   gene   PTEN.   Normally   this  gene   is   responsible   for   the  conversion  of  PIP3  to   PIP2.   However   if   PIP3   levels   stay   elevated,  Akt   can   be   activated   without   EGFR   activity.  This  will  result  in  cell  growth  and  inhibition  of  apoptosis  (Figure  3)  (Yamamoto  et  al.  2010).      ALK/ROS1-­‐RECEPTOR.  Anaplastic   Lymphoma   Kinase   (ALK)   is   a  tyrosine  kinase   receptor  of   the   insulin   family,  it   is   an   important   receptor   in   the   central  nervous   system   where   its   expression   levels  are   low   (Iwahara   et   al.   1997).   Through   the  RAS,  PLCγ  and  STAT  pathways  ALK   is   involved  in  cell  division  and  cell  proliferation  (Figure  1).  Changes   in   ALK   can   give   rise   to   a   permanent  active   ALK   complex.   In   3-­‐4%   of   the   cases  NSCLC   is   caused   by   a   chromosomal  translocation   of   ALK   and   the   echinoderm  microtubule-­‐associated   protein-­‐like   4   (EML4);    a   protein   necessary   for   the   formation   of  microtubules.   This   translocation   will   fuse   the  3’   kinase   domain   of   ALK   with   ELM4   and   its  promoter,   as   a   result   the     translocation  generates  an  ELM4-­‐ALK   fusion  protein,  which  leads  to  ALK  activation     (Selinger  et  al.  2013).  Therefore  ALK  will  be  present   in   relative  high  concentrations  in  all  kinds  of  tissues,  while  it  is  generally   only   present   in   the   central   nervous  system   (Jiang   et   al.   2013).   Furthermore,  because   the   fusion   disturbs   the   coiled   coil  domain   of   the   receptor,   ELM4-­‐ALK   is   able   to  

dimerize   without   the   ligand   of   ALK.   This  process   can   lead   to   a   signal   independent  kinase  activity,  which  can   inhibit  apoptosis  or  stimulate   cell   proliferation   and   division.   The  above-­‐mentioned   mechanism   is   the   most  common   type   of   ALK   activation   in   NSCLC  patients   (Selinger   et   al.   2013).   Although   the  cause   of   the   underlying   mechanism   is  completely   different,   both   the   ALK   mutation  and  EGFR  mutation  have  the  same  pathology.  For  this  reason  it  is  not  possible  to  identify  the  cause   of   NSCLC   just   with   the   clinical   picture.  Because  there  are  two  groups  of  patients  with  different   targets   it   is   important   to   have   a  thorough  test  to  decide  whether  a  patient  has  ELM4-­‐ALK  or  EGFR  related  NSCLC,  more  about  this  in  the  diagnostic  section.    

Another   receptor   that   can  play   a   role  in   NSCLC   is   the   ROS1   receptor.   Like   the   ALK  receptor  ROS1   is  a   tyrosine  kinase   insulin-­‐like  receptor,   which   can   form   fusion   proteins   as  well.  Approximately  1.6%  of  the  patients  have  NSCLC  due   to   a   fusion   in  ROS1.   There   are   14  different  genes   for   the   fusion  with   the  ROS1-­‐terosine   kinase   domain   that   can   lead   to  NSCLC.   The   most   common   is   the   SDC4-­‐ROS1  fusion,   SDC4   is   generally   a   trans-­‐   membrane  structure  that  is  involved  in  the  attachment  of  extracellular   structures   (Stumpfova,   Janne  2012).  Like  the  EML4-­‐ALK  fusion  ROS1  fusions  are   oncogenic   because   the   receptor   can  dimerize   without   ligand.   Moreover,   some  fusions   deliver   a   stronger   promoter,   that   can  lead   to   a   higher   transcription   rate.   This   can  result   in  high  receptor  concentrations   in  both  ALK  and  ROS1.  

DIAGNOSTICS  OF  NSCLC  For   an   effective   NSCLC   treatment   it   is  important   that   the   molecular   background   of  the   patient   is   thoroughly   examined.   This   is  because   ALK   related   NSCLC   has   the   same  pathology  compared  to  EGFR  related  NSCLC.  If,  for   example,   a   patient   has   a   mutated   EGFR  receptor,   an   ALK-­‐TKI   drug   will   obviously   not  work.   An   effective   method   to   test   for   AKL-­‐translocation  is  ‘break  apart  fluorescent  in  situ  hybridization’   (FISH).   Both   genes   are  positioned   on   the   short   arm   (p)   of  chromosome  2:  EML4   is   located  on  2p21  and  ALK   is   located   on   locus   2p23   (Figure   4).   This  

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technique  uses  two  locus  specific  probes  (LSP)  with  different  colors.  A  red  probe  binds  to  the  last   (3’   end)   part   of   the   ALK   gene,   the   green  probe   covers   a   piece   of   the   enhancer-­‐promoter  region  of  the  EML4  gene  (Shaw  et  al.  2009).   If   a   NSCLC   patient   has   an   EML4-­‐ALK  fusion   gene   because   of   break   resulting   in   a  translocation   or   inversion,   it   is   easily  recognized   with   a   fluorescent   microscope.  This  will   be   visible   as   separate   red  and  green  dots.   If   the   probes   are   close   together,   it   is  often   visible   as   a   yellow   dot   (Figure   4E).   If  more   than   50%   of   the   cells   have   a  chromosomal   translocation   pattern,   the  patient  is  EML4-­‐ALK  positive.  If,  however,   less  that  10%  of  the  cells  are  negative,  the  patient  is  considered  EML4-­‐ALK  negative.    

 Figure  4:  Translocation  leading  to  ELM4-­‐ALK.  4A:  In  the  wild  type  chromosome  the  FISH  probes  are  close  together,  after  the  translocation  the  probes  are  separated.  Wild  type  cells  are  shown  in  4B  and  4D,  the  mutated  cells  are  shown  in  figure  4C  and  4E  analyzed  with  immunohistochemistry  and  FISH  respectively.  This  picture  is  modified  from  (Selinger  et  al.  2013).  

     

When   the   results   of   the   positive   cells   are  >10%  and   <50%,   another   50   cells   are   scored.  When   15%   of   these   cells   shows   a  chromosomal   translocation,   the   test   is  considered   positive   (Teixidó   2014).   Similarly,  ROS1   translocations   can   be   identified   with  break   apart   FISH   as   well.   Because   of   this  arbitrary   cutoff   of   15%   some   patients   are  classified  as  EML4-­‐ALK  or  SDC4-­‐ROS1  negative.  In   the   past   a   patient   with   13%   positive   cells  was   regarded   as   EML4-­‐ALK   negative   while  being   EML4-­‐ALK   positive.   In   addition,   if   an  inversion  involves  a  small   locus   it  could  result  in  a  false  negative  as  well  (Soda  et  al.  2007).    

A   second   technique   is   the  use  of   IHC,  there   are   several   antibody’s   (ALK1,   5A4   and  D5F3)  on  the  market  with  the  same  specificity  compared  to  a  break  apart  FISH  test  (Figure  4B,  4C)   (Selinger   et   al.   2013).   Although   it   is   a  promising  and  easy   technique,   the  use  of   IHC  is  unfortunately  not  commercially  available   in  a  lot  of  countries  like  the  US  because  it   is  not  approved  by  the  food  and  drug  administration  (FDA).   It   is   also   possible   to   screen   NSCLC  patients  with  RT-­‐PCR,  this  is  a  rapid  and  cheap  identification  method   for   each  unique   known  variant.   The   problem   with   this   technique  however   is   that   a   specific   probe   is   required.  For   this   reason   unknown   variants  will   not   be  detected   (Fu   et   al.   2014).   The   the   most  effective   method   for   the   screening   of   a  translocation   seems   to   be   IHC,   especially  when   it   is   commercially   available   in   all  countries.    

EGFR-­‐TKI  RESISCTANC:  NEW  APPROACH  To  overcome  the  resistance  against  EGFR-­‐TKI’s  and  researchers  came  up  with  new  generation  of  promising  EGFR-­‐TKI’s  like  crizotinib  (Xalori®),  afatinib   and  WZ4002.   Crizotinib   is   capable   of  inhibiting   the   ALK,   ROS1   and  MET   receptors.  Like   other   TKI’s   crizotinib   competes  with  ATP  for   the   binding   sites   on   the   tyrosine   kinase  domain   of   these   receptors.   This   drug   is  already  been  used  for  the  treatment  of  EML4-­‐ALK   NSCLC   patients   and   is   approved   by   the  FDA  since  august  2011  (Ou  et  al.  2012,  Rodig,  Shapiro   2010).   WZ4002   is   a   third   generation  mutant-­‐selective  irreversible  EGFR-­‐TKI.    

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PROTO-­‐ONCOGENE  TYROSINE-­‐KINASE:  SRC  Recent   studies   showed   that   the   previous  mentioned  mutations  like  the  gatekeeper  and  MET   amplification   are   not   the   only   ways   a  NSCLC   tumor   can   acquire   resistance   to  gefitinib  and  afatinib.  There  are  several  other  alternative   kinases   that   can   activate   the  downstream   signaling   pathways.   The   Proto-­‐oncogene   SRC   for   instance   is   a   non-­‐receptor  tyrosine   kinase   that   is   capable   of  phosphorylating   many   other   proteins  (Wheeler,   Iida   &   Dunn   2009).   One   of   the  proteins   that   can   be   activated   by   Src   is   the  intracellular   part   of   the   MET-­‐receptor.  Therefore   HGF-­‐independent   activation   of   the  MET   receptor   is   possible   through   Scr  activation,   this   is   commonly   seen   in   erlotinib  resistant  cells  (Stabile  et  al.  2013).  In  addition,  Src   is   capable   of   activating   the   AKT,   RAS   and  STAT   pathways.   To   block   these   downstream  signaling  pathways  a  Src  inhibitor  can  be  used.  Moreover,   Src   can   inhibit   Anoikis.   This   is   a  form  of  programmed  cell  death  like  apoptosis,  it’s   normally   mediated   through   the  detachment   of   the   cell   and   the   extracellular  matrix   in   anchorage-­‐dependent   cells.   This  process   can   inhibited   by   Src.   Because   of   Src  activation   the   lung   tumor   can   become  resistant   to   anoiksis   (Sakuma   et   al.   2010).   A  Japanese  study  showed  that  WZ4002  is  able  to  block   the   Scr   pathway   more   efficiently  compared   to   Src   inhibitors   in   lung  adenocarcinomas   and   other   types   of   NSCLC.  This  was  tested  with  the  HCC827  (del  747-­‐750)  and   the   H1975   (double   mutation:  T790M/L858R)  cell  lines  (Sakuma  et  al.  2012).    

EFFICACY  OF  THE  NEW  GENERATION  EGFR-­‐TKI  AND  CRIZOTINIB  DUAL  TREATMENT    To  compare  the  effect  of  crizotinib  alone  or  in  combination   with   afatinib   and   WZ4002,  Japanese   researchers   used   different   NSCLC  cell  types  (Nanjo  et  al.  2013).  The  first  cell  line  is  an  EGFR  mutant  with  a  deletion   in  exon  19  resulting   in   a   high   expression   of   the   EGFR  receptor.   Secondly,   MET   amplification   cells  were   used,   these   cells   have   the   same  deletions  with  a  MET  gene  amplification  (Suda  et   al.   2010).   Thirdly,   the   researchers   used  NSCLC   cells   with   the   T790M   mutation.   The  cells   were   exposed   to   increasing  

concentrations   of   EGFR-­‐TKI’s:     afatinib   and  WZ4002.   At   the   same   time   the   cells   were  exposed   to   crizotinib   (ALK,   ROS1   and   MET  inhibitor),   HGF   and   the   combination   of  crizotinib  and  HGF  while   the  cell  proliferation  was  monitored.  In  both  the  cell  lines  crizotinib  and   afatinib   reduced   proliferation.   However,  the   external   added   HGF   generated   EGFR-­‐TKI  resistance,   this   process   could   be   reduced   by  the  use  of  an  EGFR-­‐TKI  and  crizotinib.  Another  experiment   showed   that   the   gefitinib    resistant   cells   were   sensitive   to   afatinib   and  WZ4002.   Although   HGF   was   exogenously  added,   crizotinib   still   sensitized   those   cells.  Furthermore,   the   combination   of   crizotinib  and   a   new   generation   EGFR-­‐TKI   reduced   cell  proliferation   significantly   in   the   MET  amplificated   cells   even   with   exogenously  added  HGF.    

These   experiments   indicate   that   the  combination   of   crizotinib   plus   WZ4002   or  afatinib   can   prevent   EGFR-­‐TKI   resistance   in  NSCLC   cells   with  MET   receptor   amplification,  HGF  overexpression  and  the  T790M  mutation  (Nanjo  et  al.  2013).  Secondly  WZ4002  is  about  30   -­‐  100   times  more  potent  compared   to   the  currently   used   EGFR-­‐TKI’s   like   afatinib   and  erlotinib,   especially   against   the   T790M   EGFR  mutant  cell  lines  (Sakuma  et  al.  2012)              

To   examine   the   efficacy   of   crizotinib  and   the   new   generation   EGFR-­‐TKI’s   (afatinib,  WZ4002)   in  vivo,  mouse  models  were  used   in  another   experiment.   NSCLC   cells   with   the  T790M   mutation   and   the   same   cells   with   a  HGF   gene   transfection   were   injected   in  immunodeficiency  (SCID)  mice.  As  a  result  the  mice   developed   tumors.   The  most   successful  treatment  of  the  T790M  HGF  transfected  cells  was   observed   with   the   combination   of  crizotinib   and   WZ4002   or   afatinib.   A  treatment   with   just   crizotinib,   afatinib   or  WZ4002   alone   was   not   effective   with   these  cells.   The   administration   of   just   afatinib   or  WZ4002   inhibited   growth   significantly   in   the  cells  with   just   the   T790M  mutation,   however  the   administration   of   only   crizotinib   was   not  effective.   This   strongly   suggests   that   the  resistance   against   EGFR-­‐TKI   is   induced  by   the  expression  of  HGF  in  vivo  (Nanjo  et  al.  2013).  

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TOXICITY  The  above  results  show  that  both  afatinib  and  WZ4002   are   quite   effective   in   combination  with   crizotinib.   However,   a   lot   of   EGFR-­‐TKI’s  can   induce   severe   side   effects.   This   is  especially  the  case  in  high  concentrations  or  in  combination   with   other   drugs.   Afatinib   for  instance   can   causes   diarrhea   and   acneiforn  (acne  like  skin  condition)  in  more  than  30%  of  the   patients.   Some   side   effects   of   EGFR-­‐TKI’s  like   deceased   appetite,   itching,   weight   loss  and  nose  bleeds  are  less  common,  they  occur  in  about  10-­‐29%  (Tao  et  al.  2014).  To  test  the  

toxicity   of   a   dual   treatment   of   afatinib   or  WZ4002   with   crizotinib   during   the   in   vivo  experiment,  Najo  and  his  group  measured  the  mice   body   weight.   The   intestinal   mucosal  damage   was   analyzed   as   well.           The   treatment   of   the   three   agents  alone   and   the   combination   of   WZ4002   and  crizotinib   had   a   minor   effect   of   intestinal  damage   or   bodyweight.   However,   the  combination  of  afatinib  and  crizotinib  cause  a  massive   drop   in   bodyweight.   Furthermore,  this   combination   induced   severe   intestinal  mucosal  damage  (Nanjo  et  al.  2013).  

 

DISCUSSION  The  use  of  crizotinib  is  already  successful  with  EML4-­‐ALK  NSCLC  patients.  In  addition,  mouse  models  and  cell  culture  experiments  show  that  the  combination  of  a  new  generation  EGFR-­‐TKI’s  (afatinib  or  WZ4002)  with  crizotinib  can  overcome  resistance  to  reversible  EGFR-­‐TKI’s  like  erlotinib  and  gefitinib.  These   results   suggest   that   the   blockage   of   both   the  mutant   EGFR   and  MET   eceptors   by   the   dual  treatment   of   crizotinib,   and   new   the   generation   EGFR-­‐TKI’s   can   be   quite   promising.    Because  the  combination  of  afatinib  and  crizotinib  can  induce  severe  side  effects  the  combination  of  crizotinib  and  WZ4002,  which   is   less   toxic,   is  more   favorable.   Furthermore   the  Src  pathway   that   is  blocked   by   WZ4002   can   actually   play   an   important   role   as   well.   In   the   future   proper   clinical  experiments   are   needed   to   test   this   combination   in   humans.   The   personal   approach   to   treat  different  types  of  NSCLC  can  only  be  performed  if  the  molecular  characteristics  are  fully  known.  This  can  be  accomplished  through  the  use  of  IHC  or  a  ‘brake  apart  FISH‘  analysis.    

 

 

 

 

 

 

 

 

 

 

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REFERENCES  

 Bulzebruck,  H.,  Bopp,  R.,  Drings,  P.,  Bauer,  E.,  Krysa,  S.,  Probst,  G.,  van  Kaick,  G.,  Muller,  K.M.  &  Vogt-­‐Moykopf,  I.  1992,  "New  aspects  in  the  staging  of  lung  cancer.  Prospective  validation  of  the  International  Union  Against  Cancer  TNM  classification",  Cancer,  vol.  70,  no.  5,  pp.  1102-­‐1110.  

Chang,  A.,  Parikh,  P.,  Thongprasert,  S.,  Tan,  E.H.,  Perng,  R.P.,  Ganzon,  D.,  Yang,  C.H.,  Tsao,  C.J.,  Watkins,  C.,  Botwood,  N.  &  Thatcher,  N.  2006,  "Gefitinib  (IRESSA)  in  patients  of  Asian  origin  with  refractory  advanced  non-­‐small  cell  lung  cancer:  subset  analysis  from  the  ISEL  study",  Journal  of  thoracic  oncology  :  official  publication  of  the  International  Association  for  the  Study  of  Lung  Cancer,  vol.  1,  no.  8,  pp.  847-­‐855.  

Ciarimboli,  G.  2014,  "Membrane  transporters  as  mediators  of  cisplatin  side-­‐effects",  Anticancer  Research,  vol.  34,  no.  1,  pp.  547-­‐550.  

Cohen,  S.  1965,  "The  stimulation  of  epidermal  proliferation  by  a  specific  protein  (EGF)",  Developmental  biology,  vol.  12,  no.  3,  pp.  394-­‐407.  

Dawson,  J.P.,  Berger,  M.B.,  Lin,  C.C.,  Schlessinger,  J.,  Lemmon,  M.A.  &  Ferguson,  K.M.  2005,  "Epidermal  growth  factor  receptor  dimerization  and  activation  require  ligand-­‐induced  conformational  changes  in  the  dimer  interface",  Molecular  and  cellular  biology,  vol.  25,  no.  17,  pp.  7734-­‐7742.  

Fu,  S.,  Wang,  F.,  Shao,  Q.,  Zhang,  X.,  Duan,  L.P.,  Zhang,  X.,  Zhang,  L.  &  Shao,  J.Y.  2014,  "Detection  of  EML4-­‐ALK  Fusion  Gene  in  Chinese  Non-­‐Small  Cell  Lung  Cancer  by  Using  a  Sensitive  Quantitative  Real-­‐Time  Reverse  Transcriptase  PCR  Technique",  Diagnostic  molecular  pathology  :  the  American  journal  of  surgical  pathology,  part  B,  .  

Fukuoka,  M.,  Yano,  S.,  Giaccone,  G.,  Tamura,  T.,  Nakagawa,  K.,  Douillard,  J.Y.,  Nishiwaki,  Y.,  Vansteenkiste,  J.,  Kudoh,  S.,  Rischin,  D.,  Eek,  R.,  Horai,  T.,  Noda,  K.,  Takata,  I.,  Smit,  E.,  Averbuch,  S.,  Macleod,  A.,  Feyereislova,  A.,  Dong,  R.P.  &  Baselga,  J.  2003,  "Multi-­‐institutional  randomized  phase  II  trial  of  gefitinib  for  previously  treated  patients  with  advanced  non-­‐small-­‐cell  lung  cancer  (The  IDEAL  1  Trial)  [corrected",  Journal  of  clinical  oncology  :  official  journal  of  the  American  Society  of  Clinical  Oncology,  vol.  21,  no.  12,  pp.  2237-­‐2246.  

Iwahara,  T.,  Fujimoto,  J.,  Wen,  D.,  Cupples,  R.,  Bucay,  N.,  Arakawa,  T.,  Mori,  S.,  Ratzkin,  B.  &  Yamamoto,  T.  1997,  "Molecular  characterization  of  ALK,  a  receptor  tyrosine  kinase  expressed  specifically  in  the  nervous  system",  Oncogene,  vol.  14,  no.  4,  pp.  439-­‐449.  

Janku,  F.,  Stewart,  D.J.  &  Kurzrock,  R.  2010,  "Targeted  therapy  in  non-­‐small-­‐cell  lung  cancer-­‐-­‐is  it  becoming  a  reality?",  Nature  reviews.Clinical  oncology,  vol.  7,  no.  7,  pp.  401-­‐414.  

Jiang,  K.,  Brownstein,  S.,  Sekhon,  H.S.,  Laurie,  S.A.,  Lam,  K.,  Gilberg,  S.  &  Britton,  W.  2013,  "Ocular  metastasis  of  lung  adenocarcinoma  with  ELM4-­‐ALK  translocation:  A  case  report  with  a  review  of  the  literature",  Saudi  journal  of  ophthalmology  :  official  journal  of  the  Saudi  Ophthalmological  Society,  vol.  27,  no.  3,  pp.  187-­‐192.  

Kobayashi,  S.,  Boggon,  T.J.,  Dayaram,  T.,  Janne,  P.A.,  Kocher,  O.,  Meyerson,  M.,  Johnson,  B.E.,  Eck,  M.J.,  Tenen,  D.G.  &  Halmos,  B.  2005,  "EGFR  mutation  and  resistance  of  non-­‐small-­‐cell  lung  cancer  to  gefitinib",  The  New  England  journal  of  medicine,  vol.  352,  no.  8,  pp.  786-­‐792.  

Page 11: FUTURE TREATMENT OF NSCLC PATIENTS WITH NEW EGFR … · 2018. 2. 15. · 3! ABSTRACT& Thetreatment&of&non>small&cell&lung&carcinoma&(NSCLC)&patients&with&epidermal&growth&factor&

   

11  

Michalczyk,  A.,  Kluter,  S.,  Rode,  H.B.,  Simard,  J.R.,  Grutter,  C.,  Rabiller,  M.  &  Rauh,  D.  2008,  "Structural  insights  into  how  irreversible  inhibitors  can  overcome  drug  resistance  in  EGFR",  Bioorganic  &  medicinal  chemistry,  vol.  16,  no.  7,  pp.  3482-­‐3488.  

Miller,  V.A.,  Kris,  M.G.,  Shah,  N.,  Patel,  J.,  Azzoli,  C.,  Gomez,  J.,  Krug,  L.M.,  Pao,  W.,  Rizvi,  N.,  Pizzo,  B.,  Tyson,  L.,  Venkatraman,  E.,  Ben-­‐Porat,  L.,  Memoli,  N.,  Zakowski,  M.,  Rusch,  V.  &  Heelan,  R.T.  2004,  "Bronchioloalveolar  pathologic  subtype  and  smoking  history  predict  sensitivity  to  gefitinib  in  advanced  non-­‐small-­‐cell  lung  cancer",  Journal  of  clinical  oncology  :  official  journal  of  the  American  Society  of  Clinical  Oncology,  vol.  22,  no.  6,  pp.  1103-­‐1109.  

Nanjo,  S.,  Yamada,  T.,  Nishihara,  H.,  Takeuchi,  S.,  Sano,  T.,  Nakagawa,  T.,  Ishikawa,  D.,  Zhao,  L.,  Ebi,  H.,  Yasumoto,  K.,  Matsumoto,  K.  &  Yano,  S.  2013,  "Ability  of  the  Met  kinase  inhibitor  crizotinib  and  new  generation  EGFR  inhibitors  to  overcome  resistance  to  EGFR  inhibitors",  PloS  one,  vol.  8,  no.  12,  pp.  e84700.  

Oda,  K.,  Matsuoka,  Y.,  Funahashi,  A.  &  Kitano,  H.  2005,  "A  comprehensive  pathway  map  of  epidermal  growth  factor  receptor  signaling",  Molecular  systems  biology,  vol.  1,  pp.  2005.0010.  

Ou,  S.H.,  Bartlett,  C.H.,  Mino-­‐Kenudson,  M.,  Cui,  J.  &  Iafrate,  A.J.  2012,  "Crizotinib  for  the  treatment  of  ALK-­‐rearranged  non-­‐small  cell  lung  cancer:  a  success  story  to  usher  in  the  second  decade  of  molecular  targeted  therapy  in  oncology",  The  oncologist,  vol.  17,  no.  11,  pp.  1351-­‐1375.  

Rodig,  S.J.  &  Shapiro,  G.I.  2010,  "Crizotinib,  a  small-­‐molecule  dual  inhibitor  of  the  c-­‐Met  and  ALK  receptor  tyrosine  kinases",  Current  opinion  in  investigational  drugs  (London,  England  :  2000),  vol.  11,  no.  12,  pp.  1477-­‐1490.  

Sakuma,  Y.,  Takeuchi,  T.,  Nakamura,  Y.,  Yoshihara,  M.,  Matsukuma,  S.,  Nakayama,  H.,  Ohgane,  N.,  Yokose,  T.,  Kameda,  Y.,  Tsuchiya,  E.  &  Miyagi,  Y.  2010,  "Lung  adenocarcinoma  cells  floating  in  lymphatic  vessels  resist  anoikis  by  expressing  phosphorylated  Src",  The  Journal  of  pathology,  vol.  220,  no.  5,  pp.  574-­‐585.  

Sakuma,  Y.,  Yamazaki,  Y.,  Nakamura,  Y.,  Yoshihara,  M.,  Matsukuma,  S.,  Nakayama,  H.,  Yokose,  T.,  Kameda,  Y.,  Koizume,  S.  &  Miyagi,  Y.  2012,  "WZ4002,  a  third-­‐generation  EGFR  inhibitor,  can  overcome  anoikis  resistance  in  EGFR-­‐mutant  lung  adenocarcinomas  more  efficiently  than  Src  inhibitors",  Laboratory  investigation;  a  journal  of  technical  methods  and  pathology,  vol.  92,  no.  3,  pp.  371-­‐383.  

Schechter,  A.L.,  Stern,  D.F.,  Vaidyanathan,  L.,  Decker,  S.J.,  Drebin,  J.A.,  Greene,  M.I.  &  Weinberg,  R.A.  1984,  "The  neu  oncogene:  an  erb-­‐B-­‐related  gene  encoding  a  185,000-­‐Mr  tumour  antigen",  Nature,  vol.  312,  no.  5994,  pp.  513-­‐516.  

Selinger,  C.I.,  Rogers,  T.M.,  Russell,  P.A.,  O'Toole,  S.,  Yip,  P.,  Wright,  G.M.,  Wainer,  Z.,  Horvath,  L.G.,  Boyer,  M.,  McCaughan,  B.,  Kohonen-­‐Corish,  M.R.,  Fox,  S.,  Cooper,  W.A.  &  Solomon,  B.  2013,  "Testing  for  ALK  rearrangement  in  lung  adenocarcinoma:  a  multicenter  comparison  of  immunohistochemistry  and  fluorescent  in  situ  hybridization",  Modern  pathology  :  an  official  journal  of  the  United  States  and  Canadian  Academy  of  Pathology,  Inc,  vol.  26,  no.  12,  pp.  1545-­‐1553.  

Shaw,  A.T.,  Yeap,  B.Y.,  Mino-­‐Kenudson,  M.,  Digumarthy,  S.R.,  Costa,  D.B.,  Heist,  R.S.,  Solomon,  B.,  Stubbs,  H.,  Admane,  S.,  McDermott,  U.,  Settleman,  J.,  Kobayashi,  S.,  Mark,  E.J.,  Rodig,  S.J.,  Chirieac,  L.R.,  Kwak,  E.L.,  Lynch,  T.J.  &  Iafrate,  A.J.  2009,  "Clinical  features  and  outcome  of  

Page 12: FUTURE TREATMENT OF NSCLC PATIENTS WITH NEW EGFR … · 2018. 2. 15. · 3! ABSTRACT& Thetreatment&of&non>small&cell&lung&carcinoma&(NSCLC)&patients&with&epidermal&growth&factor&

   

12  

patients  with  non-­‐small-­‐cell  lung  cancer  who  harbor  EML4-­‐ALK",  Journal  of  clinical  oncology  :  official  journal  of  the  American  Society  of  Clinical  Oncology,  vol.  27,  no.  26,  pp.  4247-­‐4253.  

Sheikh,  N.  &  Chambers,  C.R.  2013,  "Efficacy  vs.  effectiveness:  erlotinib  in  previously  treated  non-­‐small-­‐cell  lung  cancer",  Journal  of  oncology  pharmacy  practice  :  official  publication  of  the  International  Society  of  Oncology  Pharmacy  Practitioners,  vol.  19,  no.  3,  pp.  228-­‐236.  

Siegel,  R.,  Ma,  J.,  Zou,  Z.  &  Jemal,  A.  2014,  "Cancer  statistics,  2014",  CA:  a  cancer  journal  for  clinicians,  vol.  64,  no.  1,  pp.  9-­‐29.  

Soda,  M.,  Choi,  Y.L.,  Enomoto,  M.,  Takada,  S.,  Yamashita,  Y.,  Ishikawa,  S.,  Fujiwara,  S.,  Watanabe,  H.,  Kurashina,  K.,  Hatanaka,  H.,  Bando,  M.,  Ohno,  S.,  Ishikawa,  Y.,  Aburatani,  H.,  Niki,  T.,  Sohara,  Y.,  Sugiyama,  Y.  &  Mano,  H.  2007,  "Identification  of  the  transforming  EML4-­‐ALK  fusion  gene  in  non-­‐small-­‐cell  lung  cancer",  Nature,  vol.  448,  no.  7153,  pp.  561-­‐566.  

Soh,  J.,  Okumura,  N.,  Lockwood,  W.W.,  Yamamoto,  H.,  Shigematsu,  H.,  Zhang,  W.,  Chari,  R.,  Shames,  D.S.,  Tang,  X.,  MacAulay,  C.,  Varella-­‐Garcia,  M.,  Vooder,  T.,  Wistuba,  I.I.,  Lam,  S.,  Brekken,  R.,  Toyooka,  S.,  Minna,  J.D.,  Lam,  W.L.  &  Gazdar,  A.F.  2009,  "Oncogene  mutations,  copy  number  gains  and  mutant  allele  specific  imbalance  (MASI)  frequently  occur  together  in  tumor  cells",  PloS  one,  vol.  4,  no.  10,  pp.  e7464.  

Stabile,  L.P.,  He,  G.,  Lui,  V.W.,  Thomas,  S.,  Henry,  C.,  Gubish,  C.T.,  Joyce,  S.,  Quesnelle,  K.M.,  Siegfried,  J.M.  &  Grandis,  J.R.  2013,  "c-­‐Src  activation  mediates  erlotinib  resistance  in  head  and  neck  cancer  by  stimulating  c-­‐Met",  Clinical  cancer  research  :  an  official  journal  of  the  American  Association  for  Cancer  Research,  vol.  19,  no.  2,  pp.  380-­‐392.  

Stumpfova,  M.  &  Janne,  P.A.  2012,  "Zeroing  in  on  ROS1  rearrangements  in  non-­‐small  cell  lung  cancer",  Clinical  cancer  research  :  an  official  journal  of  the  American  Association  for  Cancer  Research,  vol.  18,  no.  16,  pp.  4222-­‐4224.  

Suda,  K.,  Murakami,  I.,  Katayama,  T.,  Tomizawa,  K.,  Osada,  H.,  Sekido,  Y.,  Maehara,  Y.,  Yatabe,  Y.  &  Mitsudomi,  T.  2010,  "Reciprocal  and  complementary  role  of  MET  amplification  and  EGFR  T790M  mutation  in  acquired  resistance  to  kinase  inhibitors  in  lung  cancer",  Clinical  cancer  research  :  an  official  journal  of  the  American  Association  for  Cancer  Research,  vol.  16,  no.  22,  pp.  5489-­‐5498.  

Tao,  H.,  Guo,  L.,  Tang,  J.,  Zhu,  Y.,  Xu,  L.,  Meng,  Q.,  Wu,  W.,  Li,  M.,  Wu,  W.,  Tong,  L.,  Wu,  H.,  Shi,  L.  &  Liu,  Z.  2014,  "Adverse  Events  of  Afatinib  as  First-­‐line  Treatment  for  Five  Cases  of  AdvancedLung  Adenocarcinoma  and  Review  of  Literature",  Zhongguo  fei  ai  za  zhi  =  Chinese  journal  of  lung  cancer,  vol.  17,  no.  4,  pp.  342-­‐346.  

Teixidó,  C.  2014,  "Concordance  of  IHC,  FISH  and  RT-­‐PCR  for  EML4-­‐ALK  rearrangements",  Translational  Lung  Cancer  Research,  vol.  3,  no.  2.  

Turke,  A.B.,  Zejnullahu,  K.,  Wu,  Y.L.,  Song,  Y.,  Dias-­‐Santagata,  D.,  Lifshits,  E.,  Toschi,  L.,  Rogers,  A.,  Mok,  T.,  Sequist,  L.,  Lindeman,  N.I.,  Murphy,  C.,  Akhavanfard,  S.,  Yeap,  B.Y.,  Xiao,  Y.,  Capelletti,  M.,  Iafrate,  A.J.,  Lee,  C.,  Christensen,  J.G.,  Engelman,  J.A.  &  Janne,  P.A.  2010,  "Preexistence  and  clonal  selection  of  MET  amplification  in  EGFR  mutant  NSCLC",  Cancer  cell,  vol.  17,  no.  1,  pp.  77-­‐88.  

Wheeler,  D.L.,  Iida,  M.  &  Dunn,  E.F.  2009,  "The  role  of  Src  in  solid  tumors",  The  oncologist,  vol.  14,  no.  7,  pp.  667-­‐678.  

Page 13: FUTURE TREATMENT OF NSCLC PATIENTS WITH NEW EGFR … · 2018. 2. 15. · 3! ABSTRACT& Thetreatment&of&non>small&cell&lung&carcinoma&(NSCLC)&patients&with&epidermal&growth&factor&

   

13  

Yamada,  T.,  Matsumoto,  K.,  Wang,  W.,  Li,  Q.,  Nishioka,  Y.,  Sekido,  Y.,  Sone,  S.  &  Yano,  S.  2010,  "Hepatocyte  growth  factor  reduces  susceptibility  to  an  irreversible  epidermal  growth  factor  receptor  inhibitor  in  EGFR-­‐T790M  mutant  lung  cancer",  Clinical  cancer  research  :  an  official  journal  of  the  American  Association  for  Cancer  Research,  vol.  16,  no.  1,  pp.  174-­‐183.  

Yamamoto,  C.,  Basaki,  Y.,  Kawahara,  A.,  Nakashima,  K.,  Kage,  M.,  Izumi,  H.,  Kohno,  K.,  Uramoto,  H.,  Yasumoto,  K.,  Kuwano,  M.  &  Ono,  M.  2010,  "Loss  of  PTEN  expression  by  blocking  nuclear  translocation  of  EGR1  in  gefitinib-­‐resistant  lung  cancer  cells  harboring  epidermal  growth  factor  receptor-­‐activating  mutations",  Cancer  research,  vol.  70,  no.  21,  pp.  8715-­‐8725.  

Yano,  S.,  Wang,  W.,  Li,  Q.,  Matsumoto,  K.,  Sakurama,  H.,  Nakamura,  T.,  Ogino,  H.,  Kakiuchi,  S.,  Hanibuchi,  M.,  Nishioka,  Y.,  Uehara,  H.,  Mitsudomi,  T.,  Yatabe,  Y.,  Nakamura,  T.  &  Sone,  S.  2008,  "Hepatocyte  growth  factor  induces  gefitinib  resistance  of  lung  adenocarcinoma  with  epidermal  growth  factor  receptor-­‐activating  mutations",  Cancer  research,  vol.  68,  no.  22,  pp.  9479-­‐9487.  

Yano,  S.,  Yamada,  T.,  Takeuchi,  S.,  Tachibana,  K.,  Minami,  Y.,  Yatabe,  Y.,  Mitsudomi,  T.,  Tanaka,  H.,  Kimura,  T.,  Kudoh,  S.,  Nokihara,  H.,  Ohe,  Y.,  Yokota,  J.,  Uramoto,  H.,  Yasumoto,  K.,  Kiura,  K.,  Higashiyama,  M.,  Oda,  M.,  Saito,  H.,  Yoshida,  J.,  Kondoh,  K.  &  Noguchi,  M.  2011,  "Hepatocyte  growth  factor  expression  in  EGFR  mutant  lung  cancer  with  intrinsic  and  acquired  resistance  to  tyrosine  kinase  inhibitors  in  a  Japanese  cohort",  Journal  of  thoracic  oncology  :  official  publication  of  the  International  Association  for  the  Study  of  Lung  Cancer,  vol.  6,  no.  12,  pp.  2011-­‐2017.  

Zhang,  H.,  Berezov,  A.,  Wang,  Q.,  Zhang,  G.,  Drebin,  J.,  Murali,  R.  &  Greene,  M.I.  2007,  "ErbB  receptors:  from  oncogenes  to  targeted  cancer  therapies",  The  Journal  of  clinical  investigation,  vol.  117,  no.  8,  pp.  2051-­‐2058.  

Zhou,  C.,  Wu,  Y.L.,  Chen,  G.,  Feng,  J.,  Liu,  X.Q.,  Wang,  C.,  Zhang,  S.,  Wang,  J.,  Zhou,  S.,  Ren,  S.,  Lu,  S.,  Zhang,  L.,  Hu,  C.,  Hu,  C.,  Luo,  Y.,  Chen,  L.,  Ye,  M.,  Huang,  J.,  Zhi,  X.,  Zhang,  Y.,  Xiu,  Q.,  Ma,  J.,  Zhang,  L.  &  You,  C.  2011,  "Erlotinib  versus  chemotherapy  as  first-­‐line  treatment  for  patients  with  advanced  EGFR  mutation-­‐positive  non-­‐small-­‐cell  lung  cancer  (OPTIMAL,  CTONG-­‐0802):  a  multicentre,  open-­‐label,  randomised,  phase  3  study",  The  lancet  oncology,  vol.  12,  no.  8,  pp.  735-­‐742.