title: Field effect in oral precancer as assessed by DNA flow cytometry and array-CGH.
abstract: OBJECTIVE
  'Field cancerization' is an accepted model for oral carcinogenesis. So far, genetically altered fields have been just reported in the presence of carcinomas. This study assessed the distant mirror fields (MFs) of oral precancer by DNA high-resolution flow cytometry (hr DNA-FCM) and array-Comparative Genomic Hybridization (a-CGH).
  
  
  METHODS
  Five leukoplakias without dysplasia (OLs), seven dysplastic leukoplakias (DOLs), and 12 corresponding visually normal and non-dysplastic MFs were analyzed. DNA aneuploidy (DNA Index, DI ≠ 1) was detected by hr DNA-FCM on DAPI stained nuclei suspensions. The epithelial DNA aneuploid subclones were FCM-sorted to obtain genomic DNA for a-CGH.
  
  
  RESULTS
  Mirror fields, OLs, and DOLs showed increasing prevalence of DNA aneuploidy of, respectively, 8%, 20%, and 57%. The average number of chromosome aberrations (Ch-Abs) was 2.8 in MFs, 3 in OLs, and 10.6 in DOLs. MFs relative to OLs and DOLs had average numbers of Ch-Abs, respectively, of 1.8 and 3.6. Ch-Abs were also observed in DNA diploid sublines, and often the same aberrations were observed in both MFs and corresponding OLs/DOLs.
  
  
  CONCLUSIONS
  DNA aneuploidy and Ch-Abs in MFs, the last ones being mainly gains, indicate an early onset of field effect in oral carcinogenesis.
authors.affiliation: Department of Clinical and Biological Sciences, Oral Medicine and Oral Oncology Section, University of Turin, Turin, Italy. monica.pentenero@unito.it
authors.forename: Monica
authors.initials: M
authors.lastname: Pentenero
authors.forename: Alessandra
authors.initials: A
authors.lastname: Donadini
authors.forename: Emanuela
authors.initials: E
authors.lastname: Di Nallo
authors.forename: Massimo
authors.initials: M
authors.lastname: Maffei
authors.forename: Roberto
authors.initials: R
authors.lastname: Marino
authors.forename: Ubaldo
authors.initials: U
authors.lastname: Familiari
authors.forename: Patrizio
authors.initials: P
authors.lastname: Castagnola
authors.forename: Sergio
authors.initials: S
authors.lastname: Gandolfo
authors.forename: Walter
authors.initials: W
authors.lastname: Giaretti
mesh_terms: D000328:Adult; D000368:Aged; D000782:Aneuploidy; D002467:Cell Nucleus / Q000648:ultrastructure; D002471:Cell Transformation, Neoplastic / Q000235:genetics / Q000473:pathology; D043171:Chromosomal Instability / Q000235:genetics; D002869:Chromosome Aberrations / Q000145:classification; D055028:Comparative Genomic Hybridization / Q000379:methods*; D004273:DNA, Neoplasm / Q000032:analysis*; D004171:Diploidy; D005260:Female; D005434:Flow Cytometry / Q000379:methods*; D005456:Fluorescent Dyes; D006801:Humans; D007211:Indoles; D007972:Leukoplakia, Oral / Q000235:genetics / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009061:Mouth Mucosa / Q000166:cytology; D009062:Mouth Neoplasms / Q000235:genetics* / Q000473:pathology; D010865:Pilot Projects; D011230:Precancerous Conditions / Q000235:genetics* / Q000473:pathology
chemical_list: D004273:DNA, Neoplasm; D005456:Fluorescent Dyes; D007211:Indoles; C007293:DAPI