title: Aurora kinase targeting in lung cancer reduces KRAS-induced transformation.
abstract: BACKGROUND
  Activating mutations in KRAS are prevalent in lung cancer and have been causally linked to the oncogenic process. However, therapies targeted to oncogenic RAS have been ineffective to date and identification of KRAS targets that impinge on the oncogenic phenotype is warranted. Based on published studies showing that mitotic kinases Aurora A (AURKA) and B (AURKB) cooperate with oncogenic RAS to promote malignant transformation and that AURKA phosphorylates RAS effector pathway components, the aim of this study was to investigate whether AURKA and AURKB are KRAS targets in lung cancer and whether targeting these kinases might be therapeutically beneficial.
  
  
  METHODS
  In order to determine whether oncogenic KRAS induces Aurora kinase expression, we used qPCR and western blotting in three different lung cell-based models of gain- or loss-of-function of KRAS. In order to determine the functional role of these kinases in KRAS-induced transformation, we generated KRAS-positive A549 and H358 cells with stable and inducible shRNA-mediated knockdown of AURKA or AURKB and evaluated transformation in vitro and tumor growth in vivo. In order to validate AURKA and/or AURKB as therapeutically relevant KRAS targets in lung cancer, we treated A549 and H358 cells, as well as two different lung cell based models of gain-of-function of KRAS with a dual Aurora kinase inhibitor and performed functional in vitro assays.
  
  
  RESULTS
  We determined that KRAS positively regulates AURKA and AURKB expression. Furthermore, in KRAS-positive H358 and A549 cell lines, inducible knockdown of AURKA or AURKB, as well as treatment with a dual AURKA/AURKB inhibitor, decreased growth, viability, proliferation, transformation, and induced apoptosis in vitro. In addition, inducible shRNA-mediated knockdown of AURKA in A549 cells decreased tumor growth in vivo. More importantly, dual pharmacological inhibiton of AURKA and AURKB reduced growth, viability, transformation, and induced apoptosis in vitro in an oncogenic KRAS-dependent manner, indicating that Aurora kinase inhibition therapy can specifically target KRAS-transformed cells.
  
  
  CONCLUSIONS
  Our results support our hypothesis that Aurora kinases are important KRAS targets in lung cancer and suggest Aurora kinase inhibition as a novel approach for KRAS-induced lung cancer therapy.
authors: Department of Biochemistry, Chemistry Institute, University of São Paulo, São Paulo, SP, Brazil. edmilson.ozorio@usp.br.
authors: Edmilson Ozorio
authors: EO
authors: Dos Santos
authors: Department of Biochemistry, Chemistry Institute, University of São Paulo, São Paulo, SP, Brazil. tatty.lobo@gmail.com.
authors: Tatiana Correa
authors: TC
authors: Carneiro-Lobo
authors: Department of Biochemistry, Chemistry Institute, University of São Paulo, São Paulo, SP, Brazil. mateusaoki@hotmail.com.
authors: Mateus Nobrega
authors: MN
authors: Aoki
authors: Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA. elevanti@bidmc.harvard.edu.|Institute of Biomedical Technologies, National Research Council (CNR), Pisa, Italy. elevanti@bidmc.harvard.edu.
authors: Elena
authors: E
authors: Levantini
authors: Department of Biochemistry, Chemistry Institute, University of São Paulo, São Paulo, SP, Brazil. basseres@iq.usp.br.
authors: Daniela Sanchez
authors: DS
authors: Bassères
mesh_terms: D000818:Animals; D064096:Aurora Kinase A / Q000037:antagonists & inhibitors / Q000378:metabolism*; D064107:Aurora Kinase B / Q000037:antagonists & inhibitors / Q000378:metabolism*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002471:Cell Transformation, Neoplastic / Q000187:drug effects / Q000473:pathology*; D055785:Gene Knockdown Techniques; D008175:Lung Neoplasms / Q000201:enzymology*; D008297:Male; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D058990:Molecular Targeted Therapy; D010641:Phenotype; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D016283:Proto-Oncogene Proteins p21(ras) / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000378:metabolism; D023041:Xenograft Model Antitumor Assays
chemical_list: C117307:KRAS protein, human; D047428:Protein Kinase Inhibitors; D034741:RNA, Small Interfering; C576917:AURKA protein, human; C576921:AURKB protein, human; D064096:Aurora Kinase A; D064107:Aurora Kinase B; D016283:Proto-Oncogene Proteins p21(ras)