Unknown,Transcriptomics,Genomics,Proteomics

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Transcription profiling of human normal prostate epithelial cells following exposure to low-dose cadmium

ABSTRACT: BACKGROUND: Cadmium (Cd) is implicated in prostate carcinogenesis but its oncogenic action remains unclear. OBJECTIVES: This study aims to decipher changes in cell growth and the transcriptome in an immortalized human normal prostate epithelial cell line (NPrEC) following exposure to low-dose Cd. METHODS: Synchronized NPrEC cells were exposed to different doses of Cd and assayed for cell viability and cell-cycle progression. Temporal changes in transcriptome were investigated by global profiling. Ingenuity Pathways Analyses were used to develop propositions about functional connections among differentially expressed genes. A neutralizing antibody was used to negate the effect of Cd-induced upregulation of TNF in NPrEC. RESULTS: Exposure of NPrEC to 2.5 microM of Cd enhanced cell viability and accelerated cell-cycle progression. Global expression profiling identified 48 genes that exhibited â?¥1.5-fold changes in expression after 4, 8, 16 and 32 hr of Cd treatment. Pathway analyses inferred a functional connection among 35 of these genes in one major network with TNF as the most prominent node. Fourteen out of the 35 genes in the network are related to TNF with 11 exhibited an average of â?¥2-fold changes in gene expression. Real-time RT-PCR confirmed the upregulation of 7 of the 11 genes (ADAM8, EDN1, IL8, IL24, IL13RA2, COX2/PTGS2 and SERPINB2) and uncovered a 28-fold transient increase in TNF expression in Cd-treated NPrEC. A TNF-neutralizing antibody effectively blocked Cd-induced elevations in the expression of these genes. CONCLUSIONS: Non-cytotoxic, low-dose Cd has growth-promoting effects on NPrEC and induces transient overexpression of TNF, leading to upregulation of genes with oncogenic and immunomodulation functions. Experiment Overall Design: A total of 19 samples were analyzed, each experimental condition having two biological replicates, except Cadmium 4hr which has only 1 sample. Cadmium-treated and control samples were taken at 0, 4, 8, 16, and 32 hours.

ORGANISM(S): Homo sapiens

SUBMITTER: Xiang Zhang

PROVIDER: E-GEOD-9951 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Transcription profiling of human normal prostate epithelial cells following exposure to low-dose cadmium

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