title: Carcinogenic ability ofSchistosoma haematobiumpossibly through oncogenic mutation ofKRASgene.
abstract: Schistosoma haematobiumis a parasitic flatworm that infects millions of people, mostly in the developing world, and is associated with high incidence of bladder cancer, although why is not clear. Previously, we have used CD-1 mice to show thatSchistosoma haematobiumtotal antigen (Sh) has a carcinogenic ability. Sh intravesically instillation induced the development of several urothelial lesions, namely nodular hyperplasia and dysplasia (LGIUN-Low Grade Intra-Urothelial Neoplasia) after 40 weeks of treatment. These results suggested that Sh induce urothelium malignization. Bladder carcinoma frequently harbours gene mutations that constitutively activate the receptor tyrosine kinase-Ras pathway for this reason we studied activating mutations inKRASgene. Twenty percent of the bladders with dysplasia presented aKRASmutation in codon 12 of exon 2. We concluded from these results that the parasite extract ofS. haematobiumhas carcinogenic ability possibly through oncogenic mutation ofKRASgene.
authors.affiliation: INSA - National Institute of Health, Department of Health Promotion, Porto, Portugal ; IPATIMUP - Institute of Pathology and Molecular Immunology of Porto University, Porto, Portugal.
authors.forename: Mónica C
authors.initials: MC
authors.lastname: Botelho
authors.affiliation: IPO - Portuguese Institute of Oncology, Department of Genetics, Porto, Portugal.
authors.forename: Isabel
authors.initials: I
authors.lastname: Veiga
authors.affiliation: CECAV - Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro (UTAD), 5001-801, Vila Real, Portugal.
authors.forename: Paula A
authors.initials: PA
authors.lastname: Oliveira
authors.affiliation: ICBAS - Institute of Biomedical Sciences Abel Salazar, Department of Cellular Biology and Immunology, Porto University, Porto, Portugal ; IPO - Portuguese Institute of Oncology, Department of Pathology, Porto, Portugal.
authors.forename: Carlos
authors.initials: C
authors.lastname: Lopes
authors.affiliation: IPO - Portuguese Institute of Oncology, Department of Genetics, Porto, Portugal ; ICBAS - Institute of Biomedical Sciences Abel Salazar, Department of Cellular Biology and Immunology, Porto University, Porto, Portugal.
authors.forename: Manuel
authors.initials: M
authors.lastname: Teixeira
authors.affiliation: INSA - National Institute of Health, Department of Health Promotion, Porto, Portugal.
authors.forename: José M Correia
authors.initials: JM
authors.lastname: da Costa
authors.affiliation: IPATIMUP - Institute of Pathology and Molecular Immunology of Porto University, Porto, Portugal ; IPO - Portuguese Institute of Oncology, Department of Pathology, Porto, Portugal.
authors.forename: José C
authors.initials: JC
authors.lastname: Machado
keywords: Schistosoma haematobium; bladder cancer; kras mutation; oncogenes