title: Biomarkers and transcription levels of cancer-related genes in cockles Cerastoderma edule from Galicia (NW Spain) with disseminated neoplasia.
abstract: Disseminated neoplasia (DN) is a pathological condition reported for several species of marine bivalves throughout the world, but its aetiology has not yet been satisfactorily explained. It has been suggested that chemical contamination could be a factor contributing to neoplasia. The aim of the present study was to compare cell and tissue biomarkers and the transcription level of cancer-related genes in cockles (Cerastoderma edule) affected by DN with those of healthy cockles in relation to chemical contaminant burdens. For this, cockles were collected from a natural bed in Cambados (Ria de Arousa, Galicia) in May 2009. The prevalence of DN was 12.36% and 3 degrees of DN severity were distinguished. No significant differences in metal accumulation, non-specific inflammatory responses and parasites were observed between healthy and DN-affected cockles. Lysosomal membrane stability was significantly reduced in cockles affected by DN, which indicates a poorer health condition. Very low frequencies of micronuclei were recorded and no significant differences were detected between DN severity groups. Haemolymph analyses showed a higher frequency of mitotic figures and binucleated cells in cockles affected by moderate and heavy DN than in healthy ones. Neoplastic animals showed significantly higher transcription levels of p53 and ras than healthy cockles and mutational alterations in ras gene sequence were detected. Low concentrations of metals, polycyclic aromatic hydrocarbons, polychlorinated biphenyls and phthalate esters were measured in cockles from Cambados. In conclusion, cockles affected by DN suffer a general stress situation and have altered patterns of cancer-related gene transcription. Further studies are in progress to elucidate mechanisms of carcinogenesis in this species.
authors.affiliation: CBET Research Group, Department Zoology and Animal Cell Biology, Research Centre for Experimental Marine Biology and Biotechnology PIE, University of the Basque Country UPV/EHU, Sarriena z/g, E-48940 Leioa, Basque Country, Spain.
authors.forename: Pamela
authors.initials: P
authors.lastname: Ruiz
authors.forename: Seila
authors.initials: S
authors.lastname: Díaz
authors.forename: Amaia
authors.initials: A
authors.lastname: Orbea
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Carballal
authors.forename: Antonio
authors.initials: A
authors.lastname: Villalba
authors.forename: Miren P
authors.initials: MP
authors.lastname: Cajaraville
mesh_terms: D000818:Animals; D001483:Base Sequence; D014408:Biomarkers, Tumor / Q000378:metabolism*; D049873:Cardiidae / Q000235:genetics* / Q000378:metabolism*; D017931:DNA Primers / Q000235:genetics; D004785:Environmental Pollutants / Q000032:analysis / Q000633:toxicity*; D052138:Genes, Neoplasm / Q000235:genetics*; D011905:Genes, ras / Q000235:genetics; D006458:Hemolymph / Q000737:chemistry / Q000166:cytology; D015162:Micronucleus Tests; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D009369:Neoplasms / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D013030:Spain; D018709:Statistics, Nonparametric; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D017931:DNA Primers; D004785:Environmental Pollutants; D016159:Tumor Suppressor Protein p53