The Hippo pathway effector, Yes-associated protein (YAP), is a transcriptional coactivator implicated in cholangiocarcinoma (CCA) pathogenesis. YAP is known to be regulated by a serine/threonine kinase relay module (MST1/2-LATS1/2) culminating in phosphorylation of YAP at Serine 127 and cytoplasmic sequestration. However, YAP also undergoes tyrosine phosphorylation, and the role of tyrosine phosphorylation in YAP regulation remains unclear. Herein, YAP regulation by tyrosine phosphorylation was examined in human and mouse CCA cells, as well as patient-derived xenograft (PDX) models. YAP was phosphorylated on tyrosine 357 (Y357) in CCA cell lines and PDX models. SRC family kinase (SFK) inhibition with dasatinib resulted in loss of YAPY357 phosphorylation, promoted its translocation from the nucleus to the cytoplasm, and reduced YAP target gene expression, including cell lines expressing a LATS1/2-resistant YAP mutant in which all serine residues were mutated to alanine. Consistent with these observations, precluding YAPY357 phosphorylation by site-directed mutagenesis (YAPY357F) excluded YAP from the nucleus. Targeted siRNA experiments identified LCK as the SFK that most potently mediated YAPY357 phosphorylation. Likewise, inducible CRISPR/Cas9-targeted LCK deletion decreased YAPY357 phosphorylation and its nuclear localization. The importance of LCK in CCA biology was demonstrated by clinical observations suggesting LCK expression levels were associated with early tumor recurrence following resection of CCA. Finally, dasatinib displayed therapeutic efficacy in PDX models. Mol Cancer Res; 16(10); 1556-67. ©2018 AACR.

• MeSH
• adaptorové proteiny signální transdukční genetika   MeSH
• buněčné jádro účinky léků   MeSH
• cholangiokarcinom farmakoterapie   genetika   patologie   MeSH
• cytoplazma účinky léků   MeSH
• dasatinib aplikace a dávkování   MeSH
• fosfoproteiny genetika   MeSH
• fosforylace účinky léků   MeSH
• lidé MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• proliferace buněk účinky léků   MeSH
• protein-serin-threoninkinasy genetika   MeSH
• regulace genové exprese u nádorů účinky léků   MeSH
• signální proteiny YAP MeSH
• signální transdukce účinky léků   MeSH
• skupina kinas odvozených od src-genu antagonisté a inhibitory   genetika   MeSH
• transkripční faktory MeSH
• tyrosin genetika   MeSH
• tyrosinkinasa p56(lck), specifická pro lymfocyty genetika   MeSH
• xenogenní modely - testy protinádorové aktivity MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Názvy látek
• adaptorové proteiny signální transdukční MeSH
• dasatinib MeSH
• fosfoproteiny MeSH
• LATS1 protein, human MeSH Prohlížeč
• LCK protein, human MeSH Prohlížeč
• protein-serin-threoninkinasy MeSH
• signální proteiny YAP MeSH
• skupina kinas odvozených od src-genu MeSH
• transkripční faktory MeSH
• tyrosin MeSH
• tyrosinkinasa p56(lck), specifická pro lymfocyty MeSH
• YAP1 protein, human MeSH Prohlížeč