title: The mutational spectrum of FOXA2 in endometrioid endometrial cancer points to a tumor suppressor role.
abstract: BACKGROUND
  Forkhead box protein A2 (FOXA2) plays an important in development, cellular metabolism and tumorigenesis. The Cancer Genome Atlas (TCGA) identified a modest frequency of FOXA2 mutations in endometrioid endometrial cancers (EEC). The current study sought to determine the relationship between FOXA2 mutation and clinicopathologic features in EEC and FOXA2 expression.
  
  
  METHODS
  Polymerase chain reaction (PCR) amplification and sequencing were used to identify mutations in 542 EEC. Western blot, quantitative reverse transcriptase PCR (qRT-PCR) and immunohistochemistry (IHC) were used to assess expression. Methylation analysis was performed using combined bisulfite restriction analysis (COBRA) and sequencing. Chi-squared, Fisher's exact, Student's t- and log-rank tests were performed.
  
  
  RESULTS
  Fifty-one mutations were identified in 49 tumors (9.4% mutation rate). The majority of mutations were novel, loss of function (LOF) (78.4%) mutations, and most disrupted the DNA-binding domain (58.8%). Six recurrent mutations were identified. Only two tumors had two mutations and there was no evidence for FOXA2 allelic loss. Mutation status was associated with tumor grade and not associated with survival outcomes. Methylation of the FOXA2 promoter region was highly variable. Most tumors expressed FOXA2 at both the mRNA and protein level. In those tumors with mutations, the majority of cases expressed both alleles.
  
  
  CONCLUSIONS
  FOXA2 is frequently mutated in EEC. The pattern of FOXA2 mutations and expression in tumors suggests complex regulation and a haploinsufficient or dominant-negative tumor suppressor function. In vitro studies may shed light on how mutations in FOXA2 affect FOXA2 pioneer and/or transcription factor functions in EEC.
authors.affiliation: Division of Gynecologic Oncology, James Comprehensive Cancer Center at The Ohio State University, Columbus, OH, United States.
authors.forename: B
authors.initials: B
authors.lastname: Smith
authors.affiliation: Division of Gynecologic Oncology, James Comprehensive Cancer Center at The Ohio State University, Columbus, OH, United States.
authors.forename: R
authors.initials: R
authors.lastname: Neff
authors.affiliation: Division of Gynecologic Oncology, James Comprehensive Cancer Center at The Ohio State University, Columbus, OH, United States.
authors.forename: D E
authors.initials: DE
authors.lastname: Cohn
authors.affiliation: Division of Gynecologic Oncology, James Comprehensive Cancer Center at The Ohio State University, Columbus, OH, United States.
authors.forename: F J
authors.initials: FJ
authors.lastname: Backes
authors.affiliation: Department of Pathology, Wexner Medical Center at The Ohio State University, Columbus, OH, United States.
authors.forename: A A
authors.initials: AA
authors.lastname: Suarez
authors.affiliation: Division of Gynecologic Oncology, Washington University School of Medicine, St. Louis, MO, United States.
authors.forename: D G
authors.initials: DG
authors.lastname: Mutch
authors.affiliation: Division of Gynecologic Oncology, James Comprehensive Cancer Center at The Ohio State University, Columbus, OH, United States.
authors.forename: C M
authors.initials: CM
authors.lastname: Rush
authors.affiliation: Division of Gynecologic Oncology, James Comprehensive Cancer Center at The Ohio State University, Columbus, OH, United States.
authors.forename: C J
authors.initials: CJ
authors.lastname: Walker
authors.affiliation: Division of Gynecologic Oncology, James Comprehensive Cancer Center at The Ohio State University, Columbus, OH, United States. Electronic address: Paul.Goodfellow@osumc.edu.
authors.forename: P J
authors.initials: PJ
authors.lastname: Goodfellow
mesh_terms: D000368:Aged; D018269:Carcinoma, Endometrioid / Q000473:pathology*; D016889:Endometrial Neoplasms / Q000235:genetics*; D004717:Endometrium / Q000378:metabolism; D005260:Female; D016147:Genes, Tumor Suppressor; D051542:Hepatocyte Nuclear Factor 3-beta / Q000235:genetics*; D006801:Humans; D008875:Middle Aged; D009154:Mutation
chemical_list: C496502:FOXA2 protein, human; D051542:Hepatocyte Nuclear Factor 3-beta