Aberrant methylation of nucleotide excision repair genes is associated with chronic arsenic poisoning
BIOMARKERS
Authors: Zhang, Aihua; Li, Huiyao; Xiao, Yun; Chen, Liping; Zhu, Xiaonian; Li, Jun; Ma, Lu; Pan, Xueli; Chen, Wen; He, Zhini
Abstract
Objective: To define whether aberrant methylation of DNA repair genes is associated with chronic arsenic poisoning.Methods: Hundred and two endemic arsenicosis patients and 36 healthy subjects were recruited. Methylight and bisulfite sequencing (BSP) assays were used to examine the methylation status of ERCC1, ERCC2 and XPC genes in peripheral blood lymphocytes (PBLs) and skin lesions of arsenicosis patients and NaAsO2-treated HaCaT cells.Results: Hypermethylation of ERCC1 and ERCC2 and suppressed gene expression were found in PBLs and skin lesions of arsenicosis patients and was correlated with the level of arsenic exposure. Particularly, the expression of ERCC1 and ERCC2 was associated with the severity of skin lesions. In vitro studies revealed an induction of ERCC2 hypermethylation and decreased mRNA expression in response to NaAsO2 treatment.Conclusion: Hypermethylation of ERCC1 and ERCC2 and concomitant suppression of gene expression might be served as the epigenetic marks associated with arsenic exposure and adverse health effects.
Comprehensive Molecular Characterization of Muscle-Invasive Bladder Cancer
CELL
Authors: Robertson, A. Gordon; Kim, Jaegil; Al-Ahmadie, Hikmat; Bellmunt, Joaquim; Guo, Guangwu; Cherniack, Andrew D.; Hinoue, Toshinori; Laird, Peter W.; Hoadley, Katherine A.; Akbani, Rehan; Castro, Mauro A. A.; Gibb, Ewan A.; Kanchi, Rupa S.; Gordenin, Dmitry A.; Shukla, Sachet A.; Sanchez-Vega, Francisco; Hansel, Donna E.; Czerniak, Bogdan A.; Reuter, Victor E.; Su, Xiaoping; Carvalho, Benilton de Sa; Chagas, Vinicius S.; Mungall, Karen L.; Sadeghi, Sara; Pedamallu, Chandra Sekhar; Lu, Yiling; Klimczak, Leszek J.; Zhang, Jiexin; Choo, Caleb; Ojesina, Akinyemi I.; Bullman, Susan; Leraas, Kristen M.; Lichtenberg, Tara M.; Wu, Catherine J.; Schultz, Nicholaus; Getz, Gad; Meyerson, Matthew; Mills, Gordon B.; McConkey, David J.; Weinstein, John N.; Kwiatkowski, David J.; Lerner, Seth P.
Abstract
We report a comprehensive analysis of 412 muscleinvasive bladder cancers characterized by multiple TCGA analytical platforms. Fifty-eight genes were significantly mutated, and the overall mutational load was associated with APOBEC-signature mutagenesis. Clustering by mutation signature identified a high-mutation subset with 75% 5-year survival. mRNA expression clustering refined prior clustering analyses and identified a poor-survival "neuronal'' subtype in which the majority of tumors lacked small cell or neuroendocrine histology. Clustering by mRNA, long non-coding RNA ( lncRNA), and miRNA expression converged to identify subsets with differential epithelial-mesenchymal transition status, carcinoma in situ scores, histologic features, and survival. Our analyses identified 5 expression subtypes that may stratify response to different treatments.