title: Loss of galectin-3 expression in mucinous colorectal carcinomas is associated with 5'CpG island methylation in Tunisian patients.
abstract: The β-galactoside-binding protein galectin-3 (gal-3) has pleitropic biological functions and has been implicated in cell growth, differentiation, adhesion, RNA processing, apoptosis, and malignant transformation. To investigate the pattern of inactivation of the gal-3 gene (LGALS3) in colorectal cancers (CRC), we studied a series of Tunisian patients with CRC to identify abnormal methylation in LGALS3 promoter using a methylation-specific PCR. We also examined the gal-3 gene expression by reverse transcription-PCR and the expression of gal-3 protein by immunohistochemistry. Analysis of DNA methylation in nonmucinous colorectal carcinomas expressing gal-3 protein showed an unmethylated profile of LGALS3 promoter, whereas gal-3 was aberrantly methylated in mucinous colorectal carcinomas. Complete loss of the gal-3 expression both at mRNA and the protein level was associated with the gal-3 methylation in the mucinous colorectal carcinomas. Our results show that methylation of the gal-3 promoter could be an important mechanism in the regulation of the expression of this gene in mucinous CRCs.
authors.affiliation: Department of Colorectal Cancer Research, UR03ES04 Science University El Manar, Tunisia. liliakria77@yahoo.com
authors.forename: Lilia Kria Ben
authors.initials: LK
authors.lastname: Mahmoud
authors.forename: Amira
authors.initials: A
authors.lastname: Arfaoui
authors.forename: Mariem
authors.initials: M
authors.lastname: Khiari
authors.forename: Ines
authors.initials: I
authors.lastname: Chaar
authors.forename: Olfa
authors.initials: O
authors.lastname: El Amine
authors.forename: Abdel Majid Ben
authors.initials: AM
authors.lastname: Hmida
authors.forename: Lasaad
authors.initials: L
authors.lastname: Gharbi
authors.forename: Sabeh Regaya
authors.initials: SR
authors.lastname: Mzabi
authors.forename: Saadia
authors.initials: S
authors.lastname: Bouraoui
mesh_terms: D024506:5' Flanking Region / Q000235:genetics; D002288:Adenocarcinoma, Mucinous / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D003106:Colon / Q000378:metabolism* / Q000473:pathology; D015179:Colorectal Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D018899:CpG Islands / Q000235:genetics; D019175:DNA Methylation; D037502:Galectin 3 / Q000235:genetics / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic; D007150:Immunohistochemistry; D011401:Promoter Regions, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014416:Tunisia
chemical_list: D037502:Galectin 3