RESUMO
Differential display-polymerase chain reaction was used to compare gene expression between human chondrosarcoma cell lines and normal cartilage. A new gene, CSAGE, has been cloned and belongs to a gene family that includes the taxol resistance associated gene (TRAG)-3. CSAGE, like TRAG-3, does not confer resistance to taxol when transfected in vitro. Both genes have alternatively spliced variants. CSAGE and TRAG-3 are expressed in chondrosarcoma, melanoma, and cartilage and testis, but not in other normal tissues. TRAG-3 has been reported to be a cancer/testis antigen. Our results suggest that CSAGE belongs to the growing list of cancer/testis antigens as well. In all of the CSAGE positive samples, the melanoma antigen gene family was also expressed. This is the first report on the expression of cancer/testis antigens in chondrosarcoma.
Assuntos
Antígenos de Neoplasias/genética , Condrossarcoma/genética , Proteínas de Neoplasias/genética , Processamento Alternativo , Sequência de Aminoácidos , Sequência de Bases , Northern Blotting , Condrossarcoma/patologia , Resistencia a Medicamentos Antineoplásicos , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Células K562 , Dados de Sequência Molecular , Paclitaxel/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Células Tumorais Cultivadas/efeitos dos fármacosRESUMO
OBJECTIVE: Atherosclerosis is influenced by the interaction of environmental and genetic susceptibility risk factors. We used global microarray expression profiling to investigate differentially regulated genes in aorta during development of atherosclerosis in a susceptible genetically modified mouse model in response to the interaction between risk factors including hyperlipidemic genotype, shear stress, diet, and age. METHODS AND RESULTS: In this study we investigated transcriptional changes in lesion-prone and lesion-resistant regions of aortas in genetically modified mice lacking both genes of the LDL receptor and the apolipoprotein B mRNA editing enzyme (LDb; Ldlr(-/-)Apobec1(-/-)). Risk factors including hyperlipidemic genotype (LDb vs. C57BL/6 wildtype), shear stress (lesion-prone vs. lesion resistant aortic regions), diet (chow vs. Western high-fat), and age (2- vs. 8-months) were studied. We hybridized aortic RNA samples with microarray chips containing probes for 45,000 mouse genes and expressed sequence tags (ESTs). Overall, the differentially expressed genes were components of 20 metabolic and physiological pathways. Notably, calcium signaling is the major pathway identified with differential regulation of 30 genes within this pathway. We also found differential expression of calcium-signaling genes in cultured primary endothelial cells from lesion-prone and lesion-resistant arterial regions (LDb mice vs. C57BL/6 controls), providing further support for involvement of calcium signaling in the pathogenesis of atherosclerosis. Moreover, we demonstrated protein expression of genes in the calcium-signaling pathway using Western blot analysis and immunofluorescence. CONCLUSIONS: Our results suggest that calcium signaling may play an important role in regulation of genes expressed in aorta during development of atherosclerosis. Calcium signaling may act via mechanistic responses to genetic, mechanical, and environmental insults that trigger an imbalance of intracellular calcium homeostasis, resulting in altered biological processes leading to lesion development.