title: Evaluation of MAGE A1 in oral squamous cell carcinoma.
abstract: MAGE A1 is a cancer testis antigen (CTA) described in a variety of human             cancers. CTAs exhibit a highly restricted tissue expression and by virtue of their             immunogenic potential, these genes are promising target molecules for cancer vaccines.             DNA hypomethylation is associated with gene regulation in several types of tumours.             The aim of this project was to identify the presence of MAGE A1 in oral squamous             cell carcinoma (OSCC) samples and to investigate the hypomethylation profile of             CpG islands situated in the promoter region of this gene. The expression of MAGE             A1 in OSCC and healthy oral mucosal samples was determined by real-time quantitative             and conventional endpoint PCR and also by immunohistochemistry staining. In addition,             to investigate the hypomethylation profile of promoter MAGE A1 CpG islands, we             performed bisulphite sequencing. Real-time quantitative and endpoint PCR assays             demonstrated a lower level of MAGE A1 transcription. Endpoint PCR showed expression             of MAGE A1 in 10% (2/20) of OSCCs. Sodium bisulphite sequencing analysis of MAGE             A1 CpG islands did not reveal a difference between OSCC and normal oral mucosal             samples. We further assessed MAGE A1 protein immunoexpression and found 80% (16/20)             of immunopositivity in OSCCs. We did not observe a correlation between the presence             of MAGE A1 protein and lower levels of transcripts. Identification of MAGE A1             protein in OSCCs and absence of immunoexpression in normal oral mucosa support             the idea that this protein can be used as a biomarker for detection of OSCC; however,             it is not associated with hypomethylation or high expression of the MAGE A1 gene.
authors.affiliation: School of Dentistry, Federal University of Minas Gerais, Belo Horizonte-MG 31270-901, Brazil.
authors.forename: Cláudia Maria
authors.initials: CM
authors.lastname: Pereira
authors.forename: Carolina Cavaliéri
authors.initials: CC
authors.lastname: Gomes
authors.forename: Jeane
authors.initials: J
authors.lastname: De Fátima Correia Silva
authors.forename: Monica
authors.initials: M
authors.lastname: Bucciarelli Rodriguez
authors.forename: Alvimar Afonso
authors.initials: AA
authors.lastname: Barbosa
authors.forename: Ricardo Santiago
authors.initials: RS
authors.lastname: Gomez
mesh_terms: D001483:Base Sequence; D014408:Biomarkers, Tumor / Q000032:analysis; D002294:Carcinoma, Squamous Cell / Q000737:chemistry* / Q000235:genetics*; D018899:CpG Islands; D019175:DNA Methylation; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D058950:Melanoma-Specific Antigens / Q000032:analysis* / Q000096:biosynthesis / Q000235:genetics*; D009061:Mouth Mucosa / Q000473:pathology; D009062:Mouth Neoplasms / Q000737:chemistry* / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic; D017422:Sequence Analysis, DNA
chemical_list: D014408:Biomarkers, Tumor; C072011:MAGEA1 protein, human; D058950:Melanoma-Specific Antigens