title: Allelic loss in amalgam-associated oral lichenoid lesions compared to oral lichen planus and mucosa.
abstract: BACKGROUND
  The amalgam-associated oral lichenoid lesion (AAOLL) shows clinical and histopathological features similar to oral lichen planus (OLP). Molecular researches to improve knowledge of pathogenesis and clinical behavior of AAOLL are still scarce.
  
  
  OBJECTIVE
  We investigated for the first time the use of loss of heterozygosity (LOH) as a molecular approach for genetic characterization of AAOLL in comparison with OLP and evaluated the cell proliferation index.
  
  
  METHODS
  The sample comprised nine AAOLLs, 10 OLPs, and eight NOMs matched by patients' gender and age. LOH was assessed using polymorphic microsatellite markers at chromosomes 9p (D9S157, D9S162, D9S171), 11q (D11S1369), and 17p (TP53, AFM238WF2). Cell proliferation was assessed by immunohistochemical expression of Ki-67 (MIB-1). The association between LOH and Ki-67 was investigated.
  
  
  RESULTS
  Loss of heterozygosity occurred in 5/9 AAOLLs and in 2/10 OLPs in at least one marker each, while NOM showed no LOH. Cell proliferation index in AAOLL ranged from 2 to 23%. There was no association between cell proliferation and LOH, independent of the marker.
  
  
  CONCLUSIONS
  Our study shows that the profile of molecular changes in AAOLL and OLP, evaluated by LOH and Ki-67 expression, is similar. Additional studies including larger samples should be performed to confirm or to refute our findings.
authors.affiliation: Department of Oral Surgery and Pathology, School of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
authors.forename: L N
authors.initials: LN
authors.lastname: Rodrigues
authors.affiliation: Department of Oral Surgery and Pathology, School of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
authors.forename: S F
authors.initials: SF
authors.lastname: Sousa
authors.affiliation: Department of Oral Surgery and Pathology, School of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Rcc
authors.initials: R
authors.lastname: Silva
authors.affiliation: Department of Community and Preventive Dentistry, School of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Mhg
authors.initials: M
authors.lastname: Abreu
authors.affiliation: Oral Pathology, School of Dentistry, Universidade Estadual do Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: F R
authors.initials: FR
authors.lastname: Pires
authors.affiliation: Department of Oral Surgery and Pathology, School of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
authors.forename: R A
authors.initials: RA
authors.lastname: Mesquita
authors.affiliation: Department of Basic Life Sciences, Life Sciences Institute, Universidade Federal de Juiz de Fora, Governador Valadares, Brazil.
authors.forename: L
authors.initials: L
authors.lastname: Bastos-Rodrigues
authors.affiliation: Department of Surgery, School of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
authors.forename: L
authors.initials: L
authors.lastname: De Marco
authors.affiliation: Department of Pathology, Biological Sciences Institute, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
authors.forename: C C
authors.initials: CC
authors.lastname: Gomes
authors.affiliation: Department of Oral Surgery and Pathology, School of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
authors.forename: R S
authors.identifier: http://orcid.org/0000-0001-8770-8009
authors.initials: RS
authors.lastname: Gomez
authors.affiliation: Department of Pathology, Biological Sciences Institute, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
authors.forename: V F
authors.identifier: http://orcid.org/0000-0003-0194-7434
authors.initials: VF
authors.lastname: Bernardes
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D049109:Cell Proliferation; D003723:Dental Amalgam / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism; D017676:Lichen Planus, Oral / Q000235:genetics / Q000503:physiopathology; D017512:Lichenoid Eruptions / Q000209:etiology* / Q000235:genetics / Q000503:physiopathology; D019656:Loss of Heterozygosity; D008297:Male; D018895:Microsatellite Repeats; D008875:Middle Aged; D009059:Mouth Diseases / Q000209:etiology* / Q000235:genetics / Q000503:physiopathology; D009061:Mouth Mucosa / Q000503:physiopathology*; D011110:Polymorphism, Genetic
chemical_list: D019394:Ki-67 Antigen; D003723:Dental Amalgam
keywords: amalgam-associated oral lichenoid lesion; cell proliferation index; loss of heterozygosity; oral lichen planus