Project description:Malignant mesothelioma is an aggressive cancer that often originates in the pleural and peritoneal mesothelium. Exposure to asbestos is a frequent cause. But studies in rodents showed that certain multiwalled carbon nanotubes (MWCNTs) can induce malignant mesotheliomas. This study aimed to understand molecular pathways leading to the development of malignant mesotheliomas induced by MWCNTs and amosite asbestos in Wistar rats. Using Affymetrix microarrays, we carried out genome-wide transcriptome analysis on malignant peritoneal meosotheliomas induced by MWCNTs and amosite asbestos. The transcriptome of MWCNTs and amosite asbestos-induced mesotheliomas exhibited commonalities, but also differences pertaining to differentially-expressed genes (DEGs), regulated canonical pathways, and molecular functions.
Project description:Malignant mesothelioma is an aggressive tumour arising from the mesothelial cells lining the pleura, peritoneum or pericardium. The principal carcinogen associated with malignant mesothelioma is asbestos . A transgenic mouse model, denoted MexTAg, which encodes the Simian Virus 40 (SV40) large T antigen (TAg) downstream of the mesothelin promoter was developed. Inactivation of the tumour suppressors p53 and RB following binding to TAg results. In this model mesothelioma develops in the mesothelial cell compartment after the mice have been exposed to asbestos. The MexTAg transgenic mouse model of mesothelioma model enables analysis of the molecular events associated with asbestos induced mesothelioma and is utilised here to investigate the molecular dynamics of tumours induced in these mice, using gene expression patterns as a read out.
Project description:Exposure to asbestos is a risk for malignant mesothelioma in humans. We carried out array comparative genomic hybridization (CGH) analysis in a rat model by repeated intraperitoneal injections of three types of asbestos including chrysotile, crocidolite and amosite. We found a common chromosomal deletion mapped to the chromosome 5q32 locus, containing the genes encoding tumour suppressor genes CDKN2A/2B/ARF. Homozygous deletion of CDKN2A/2B/ARF was observed in the majority (92.6%) of the rat MM samples.
Project description:Exposure to asbestos is a risk for malignant mesothelioma in humans. We carried out array comparative genomic hybridization (CGH) analysis in a rat model by repeated intraperitoneal injections of three types of asbestos including chrysotile, crocidolite and amosite. We found a common chromosomal deletion mapped to the chromosome 5q32 locus, containing the genes encoding tumour suppressor genes CDKN2A/2B/ARF. Homozygous deletion of CDKN2A/2B/ARF was observed in the majority (92.6%) of the rat MM samples. Carcinogenesis protocol was performed using specific pathogen-free male and female F1 hybrid rats between Fischer344 and Brown-Norway strains. A total of 27 tumor samples were profiled on Agilent 244A aCGH arrays according to manufacturer's instructions for the screening purpose.
Project description:Human malignant mesothelioma (MM) is an aggressive tumor strongly associated with asbestos exposure. SM patients generally have poorer prognosis compared to EM patients. To identify potential genes accounting for the differential prognosis between these two subtypes, we compared the microarray gene expression profiles of rat SM and EM tissues induced by intraperitoneal injections of 3 types of asbestos (chrysotile,crocidolite and amosite).
Project description:Human malignant mesothelioma (MM) is an aggressive tumor strongly associated with asbestos exposure. SM patients generally have poorer prognosis compared to EM patients. To identify potential genes accounting for the differential prognosis between these two subtypes, we compared the microarray gene expression profiles of rat SM and EM tissues induced by intraperitoneal injections of 3 types of asbestos (chrysotile,crocidolite and amosite). Carcinogenesis protocol was performed using specific pathogen-free male and female F1 hybrid rats between Fischer344 and Brown-Norway strains. A total of 28 microarrays (Whole Rat Genome Microarray) were used for screening purpose: The 2 arrays were used for knife-scraped peritoneal mesothelial cells, 2 arrays for cultured peritoneal mesothelial cells and 24 arrays for MM samples.
Project description:Asbestos has been shown to cause chromosomal damage and DNA aberrations. The fiber is associated with many different lung diseases such as asbestosis, malignant mesothelioma, and lung cancer, but the disease-related processes are still largely unknown. Our aim was to identify specific gene expression profiles by using Affymetrix arrays, in human cell lines A549, Beas-2B, and MeT5A exposed to asbestos in a time-dependent manner. The hybridization data was analyzed using an algorithm specifically designed for clustering short time series expression data, a canonical correlation analysis (CCA) for identifying correlations between the cell lines, and a Gene Ontology (GO) analysis method for the identification of enriched differentially expressed biological processes. Keywords: time course, gene expression, cell line, asbestos