title: Defects in the Fanconi Anemia Pathway in Head and Neck Cancer Cells Stimulate Tumor Cell Invasion through DNA-PK and Rac1 Signaling.
abstract: OBJECTIVE
  Head and neck squamous cell carcinoma (HNSCC) remains a devastating disease, and Fanconi anemia (FA) gene mutations and transcriptional repression are common. Invasive tumor behavior is associated with poor outcome, but relevant pathways triggering invasion are poorly understood. There is a significant need to improve our understanding of genetic pathways and molecular mechanisms driving advanced tumor phenotypes, to develop tailored therapies. Here we sought to investigate the phenotypic and molecular consequences of FA pathway loss in HNSCC cells.
  
  
  METHODS
  Using sporadic HNSCC cell lines with and without FA gene knockdown, we sought to characterize the phenotypic and molecular consequences of FA deficiency. FA pathway inactivation was confirmed by the detection of classic hallmarks of FA following exposure to DNA cross-linkers. Cells were subjected to RNA sequencing with qRT-PCR validation, followed by cellular adhesion and invasion assays in the presence and absence of DNA-dependent protein kinase (DNA-PK) and Rac1 inhibitors.
  
  
  RESULTS
  We demonstrate that FA loss in HNSCC cells leads to cytoskeletal reorganization and invasive tumor cell behavior in the absence of proliferative gains. We further demonstrate that cellular invasion following FA loss is mediated, at least in part, through NHEJ-associated DNA-PK and downstream Rac1 GTPase activity.
  
  
  CONCLUSIONS
  These findings demonstrate that FA loss stimulates HNSCC cell motility and invasion, and implicate a targetable DNA-PK/Rac1 signaling axis in advanced tumor phenotypes.
authors.affiliation: Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
authors.forename: Lindsey E
authors.initials: LE
authors.lastname: Romick-Rosendale
authors.affiliation: Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
authors.forename: Elizabeth E
authors.initials: EE
authors.lastname: Hoskins
authors.affiliation: Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Privette Vinnedge
authors.affiliation: Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
authors.forename: Grant D
authors.initials: GD
authors.lastname: Foglesong
authors.affiliation: Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
authors.forename: Marion G
authors.initials: MG
authors.lastname: Brusadelli
authors.affiliation: Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
authors.forename: S Steven
authors.initials: SS
authors.lastname: Potter
authors.affiliation: Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
authors.forename: Kakajan
authors.initials: K
authors.lastname: Komurov
authors.affiliation: Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
authors.forename: Samantha A
authors.initials: SA
authors.lastname: Brugmann
authors.affiliation: McArdle Laboratory for Cancer Research, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin.
authors.forename: Paul F
authors.initials: PF
authors.lastname: Lambert
authors.affiliation: Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin.
authors.forename: Randall J
authors.initials: RJ
authors.lastname: Kimple
authors.affiliation: Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana.
authors.forename: Elizabeth L
authors.initials: EL
authors.lastname: Virts
authors.affiliation: Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana. Department of Otorhinolaryngology, Heinrich Heine University, Duesseldorf, Germany. Department of Pediatrics III, University Children's Hospital Essen, University of Duisburg-Essen, Essen, Germany.
authors.forename: Helmut
authors.initials: H
authors.lastname: Hanenberg
authors.affiliation: Internal Medicine-Hematology & Oncology, Comprehensive Cancer Center, The Ohio State, University College of Medicine, Columbus, Ohio.
authors.forename: Maura L
authors.initials: ML
authors.lastname: Gillison
authors.affiliation: Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio. Susanne.Wells@cchmc.org.
authors.forename: Susanne I
authors.initials: SI
authors.lastname: Wells
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics; D019295:Computational Biology / Q000379:methods; D003599:Cytoskeleton / Q000378:metabolism; D051747:DNA-Activated Protein Kinase / Q000378:metabolism*; D051856:Fanconi Anemia Complementation Group Proteins / Q000235:genetics / Q000378:metabolism*; D020869:Gene Expression Profiling; D055785:Gene Knockdown Techniques; D063990:Gene Ontology; D006258:Head and Neck Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D010641:Phenotype; D015398:Signal Transduction; D000077195:Squamous Cell Carcinoma of Head and Neck; D020830:rac1 GTP-Binding Protein / Q000378:metabolism*
chemical_list: D051856:Fanconi Anemia Complementation Group Proteins; D051747:DNA-Activated Protein Kinase; D020830:rac1 GTP-Binding Protein