title: Association between dense CADM1 promoter methylation and reduced protein expression in high-grade CIN and cervical SCC.
abstract: We previously showed that silencing of TSLC1, recently renamed CADM1, is functionally involved in high-risk HPV-mediated cervical carcinogenesis. CADM1 silencing often results from promoter methylation. Here, we determined the extent of CADM1 promoter methylation in cervical (pre)malignant lesions and its relation to anchorage-independent growth and gene silencing to select a CADM1-based methylation marker for identification of women at risk of cervical cancer. Methylation-specific PCRs targeting three regions within the CADM1 promoter were performed on high-risk HPV-containing cell lines, PBMCs, normal cervical smears, and (pre)malignant lesions. CADM1 protein expression in cervical tissues was analysed by immunohistochemistry. All statistical tests were two-sided. Density of methylation was associated with the degree of anchorage-independent growth and CADM1 gene silencing in vitro. In cervical squamous lesions, methylation frequency and density increased with severity of disease. Dense methylation (defined as >or= 2 methylated regions) increased from 5% in normal cervical samples to 30% in CIN3 lesions and 83% in squamous cell carcinomas (SCCs) and was significantly associated with decreased CADM1 protein expression (p < 0.00005). The frequency of dense methylation was significantly higher in >or= CIN3 compared with <or= CIN1 (p = 0.005), as well as in SCCs compared with adenocarcinomas (83% versus 23%; p = 0.002). Detection of dense CADM1 promoter methylation will contribute to the assembly of a valuable marker panel for the triage of high-risk HPV-positive women at risk of >or= CIN3.
authors.affiliation: Department of Pathology, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: R M
authors.initials: RM
authors.lastname: Overmeer
authors.forename: F E
authors.initials: FE
authors.lastname: Henken
authors.forename: P J F
authors.initials: PJ
authors.lastname: Snijders
authors.forename: D
authors.initials: D
authors.lastname: Claassen-Kramer
authors.forename: J
authors.initials: J
authors.lastname: Berkhof
authors.forename: T J M
authors.initials: TJ
authors.lastname: Helmerhorst
authors.forename: D A M
authors.initials: DA
authors.lastname: Heideman
authors.forename: S M
authors.initials: SM
authors.lastname: Wilting
authors.forename: Y
authors.initials: Y
authors.lastname: Murakami
authors.forename: A
authors.initials: A
authors.lastname: Ito
authors.forename: C J L M
authors.initials: CJ
authors.lastname: Meijer
authors.forename: R D M
authors.initials: RD
authors.lastname: Steenbergen
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis*; D015153:Blotting, Western; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000378:metabolism; D016022:Case-Control Studies; D000075982:Cell Adhesion Molecule-1; D015815:Cell Adhesion Molecules; D002461:Cell Line, Transformed; D019175:DNA Methylation; D005260:Female; D020868:Gene Silencing; D006801:Humans; D007136:Immunoglobulins / Q000032:analysis / Q000235:genetics*; D007150:Immunohistochemistry; D016015:Logistic Models; D008565:Membrane Proteins / Q000032:analysis / Q000235:genetics*; D011401:Promoter Regions, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D025521:Tumor Suppressor Proteins / Q000032:analysis / Q000235:genetics*; D002583:Uterine Cervical Neoplasms / Q000235:genetics* / Q000378:metabolism; D002578:Uterine Cervical Dysplasia / Q000235:genetics* / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; C403514:CADM1 protein, human; D000075982:Cell Adhesion Molecule-1; D015815:Cell Adhesion Molecules; D007136:Immunoglobulins; D008565:Membrane Proteins; D025521:Tumor Suppressor Proteins