title: Epithelial mesenchymal transition status is associated with anti-cancer responses towards receptor tyrosine-kinase inhibition by dovitinib in human bladder cancer cells.
abstract: BACKGROUND
  Dovitinib (TKI-258) is a receptor tyrosine kinase (RTK) inhibitor targeting fibroblast growth factor receptor (FGFR) and further related RTKs. TKI-258 is under investigation as anticancer drug for the treatment of various cancers including bladder cancer with aberrant RTK signaling. Here, we analyzed the responses of ten human bladder cancer cell lines towards TKI-258 treatment in relation to the epithelial mesenchymal transition (EMT) status of the cells.
  
  
  METHODS
  Expression of epithelial marker E-cadherin as well as mesenchymal markers N-cadherin and vimentin was determined by quantitative RT-PCR and Western-blot in RNA and protein extracts from the cultured cell lines. The cell responses were analyzed upon addition of TKI-258 by viability/proliferation (XTT assay) and colony formation assay for measurement of cell contact independent growth.
  
  
  RESULTS
  The investigated bladder cancer cell lines turned out to display quite different EMT patterns as indicated by the abundance of E-cadherin or N-cadherin and vimentin. Protein and mRNA levels of the respective components strongly correlated. Based on E-cadherin and N-cadherin mRNA levels that were expressed approximately mutual exclusively, an EMT-score was calculated for each cell line. A high EMT-score indicated mesenchymal-like cells and a low EMT-score epithelial-like cells. Then, we determined the IC₅₀ values for TKI-258 by dose response curves (0-12 μM TKI-258) in XTT assays for each cell line. Also, we measured the clonogenic survival fraction after adding TKI-258 (1 μM) by colony formation assay. We observed significant correlations between EMT-score and IC₅₀ values (r = 0.637, p = 0.0474) and between EMT-score and clonogenic survival fraction (r = 0.635, p = 0.0483) as analyzed by linear regression analyses.
  
  
  CONCLUSIONS
  In sum, we demonstrated that the EMT status based on E-cadherin and N-cadherin mRNA levels may be useful to predict responses towards TKI-258 treatment in bladder cancer.
authors: Department of Urology and Pediatric Urology, Philipps University of Marburg, Baldingerstraße, 35043 Marburg, Germany. joerg.haenze@med.uni-marburg.de.
authors: Jörg
authors: J
authors: Hänze
authors: Marcus
authors: M
authors: Henrici
authors: Axel
authors: A
authors: Hegele
authors: Rainer
authors: R
authors: Hofmann
authors: Peter J
authors: PJ
authors: Olbert
mesh_terms: D015703:Antigens, CD / Q000378:metabolism; D000970:Antineoplastic Agents / Q000494:pharmacology*; D001562:Benzimidazoles / Q000494:pharmacology*; D015820:Cadherins / Q000378:metabolism; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D004354:Drug Screening Assays, Antitumor; D058750:Epithelial-Mesenchymal Transition / Q000187:drug effects*; D015870:Gene Expression; D006801:Humans; D020128:Inhibitory Concentration 50; D015363:Quinolones / Q000494:pharmacology*; D020794:Receptor Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D051498:Receptor, Fibroblast Growth Factor, Type 3 / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D001749:Urinary Bladder Neoplasms; D014746:Vimentin / Q000378:metabolism
chemical_list: C500007:4-amino-5-fluoro-3-(5-(4-methylpiperazin-1-yl)-1H-benzimidazol-2-yl)quinolin-2(1H)-one; D015703:Antigens, CD; D000970:Antineoplastic Agents; D001562:Benzimidazoles; C513384:CDH1 protein, human; C050361:CDH2 protein, human; D015820:Cadherins; D015363:Quinolones; D014746:Vimentin; C496365:FGFR3 protein, human; D020794:Receptor Protein-Tyrosine Kinases; D051498:Receptor, Fibroblast Growth Factor, Type 3