Genetic variation in the nuclear factor kappa B pathway in relation to susceptibility to rheumatoid arthritis
ANNALS OF THE RHEUMATIC DISEASES
Authors: Dieguez-Gonzalez, R.; Akar, S.; Calaza, M.; Perez-Pampin, E.; Costas, J.; Torres, M.; Vicario, J. L.; Velloso, M. L.; Navarro, F.; Narvaez, J.; Joven, B.; Herrero-Beaumont, G.; Gonzalez-Alvaro, I.; Fernandez-Gutierrez, B.; de la Serna, A. R.; Carreno, L.; Lopez-Longo, J.; Caliz, R.; Collado-Escobar, M. D.; Blanco, F. J.; Fernandez-Lopez, C.; Balsa, A.; Pascual-Salcedo, D.; Gomez-Reino, J. J.; Gonzalez, A.
Abstract
Objective: To examine genetic association between rheumatoid arthritis (RA) and known polymorphisms in core genes of the nuclear factor (NF)kappa B pathway, the major intracellular pathway in RA pathogenesis. Methods: Discovery and replication sample sets of Spanish patients with RA and controls were studied. A total of 181 single nucleotide polymorphisms ( SNPs) uniformly spaced along the genomic sequences of 17 core genes of the NFkB pathway (REL, RELA, RELB, NFKB1, NFKB2, NFKBIA, NFKBIB, NFKBIE, IKBKA, IKBKB, IKBKE, IKBKAP, KBRAS1, KBRAS2, MAP3K1, MAP3K14, TAX1BP1) were studied by mass spectrometry analysis complemented with 5'-nuclease fluorescence assays in the discovery set, 458 patients with RA and 657 controls. SNPs showing nominal significant differences were further investigated in the replication set of 1189 patients with RA and 1092 controls. Results: No clear reproducible association was found, although 12 SNPs in IKBKB, IKBKE and REL genes showed significant association in the discovery set. Interestingly, two of the SNPs in the IKBKE gene, weakly associated in the discovery phase, showed a trend to significant association in the replication phase. Pooling both sample sets together, the association with these two SNPs was significant. Conclusion: We did not find any major effect among the explored members of the NF-kappa B pathway in RA susceptibility. However, it is possible that variation in the IKBKE gene could have a small effect that requires replication in additional studies.
Integrated Genomics Reveals Convergent Transcriptomic Networks Underlying Chronic Obstructive Pulmonary Disease and Idiopathic Pulmonary Fibrosis
AMERICAN JOURNAL OF RESPIRATORY AND CRITICAL CARE MEDICINE
Authors: Kusko, Rebecca L.; Brothers, John F., II; Tedrow, John; Pandit, Kusum; Huleihel, Luai; Perdomo, Catalina; Liu, Gang; Juan-Guardela, Brenda; Kass, Daniel; Zhang, Sherry; Lenburg, Marc; Martinez, Fernando; Quackenbush, John; Sciurba, Frank; Limper, Andrew; Geraci, Mark; Yang, Ivana; Schwartz, David A.; Beane, Jennifer; Spira, Avrum; Kaminski, Naftali
Abstract
Rationale: Despite shared environmental exposures, idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease are usually studied in isolation, and the presence of shared molecular mechanisms is unknown. Objectives: We applied an integrative genomic approach to identify convergent transcriptomic pathways in emphysema and IPF. Methods: We defined the transcriptional repertoire of chronic obstructive pulmonary disease, IPF, or normal histology lungs using RNA-seq (n = 87). Measurements and Main Results: Genes increased in both emphysema and IPF relative to control were enriched for the p53/hypoxia pathway, a finding confirmed in an independent cohort using both gene expression arrays and the nCounter Analysis System (n = 193). Immunohistochemistry confirmed overexpression of HIFIA, MDM2, and NFKBIB members of this pathway in tissues from patients with emphysema or IPF. Using reads aligned across splice junctions, we determined that alternative splicing of p53/hypoxia pathway-associated molecules NUMB and PDGFA occurred more frequently in IPF or emphysema compared with control and validated these findings by quantitative polymerase chain reaction and the nCounter Analysis System on an independent sample set (n = 193). Finally, by integrating parallel microRNA and mRNA-Seq data on the same samples, we identified MIR96 as a key novel regulatory hub in the p53/hypoxia gene-expression network and confirmed that modulation of MIR96 in vitro recapitulates the disease-associated gene-expression network. Conclusions: Our results suggest convergent transcriptional regulatory hubs in diseases as varied phenotypically as chronic obstructive pulmonary disease and IPF and suggest that these hubs may represent shared key responses of the lung to environmental stresses.