RESUMO
BACKGROUND: Anti-tumour necrosis factor α (TNFα) therapy effectively induces and maintains remission in Crohn's disease (CD). Up to 40% of patients, however, fail to respond to anti-TNFα. OBJECTIVE: To identify the mechanisms underlying the persistence of mucosal lesions in patients who fail to respond to anti-TNFα therapy. DESIGN: An observational study based on whole-genome transcriptional analysis was carried out using intestinal biopsy specimens from patients with CD receiving (n=12) or not (n=10) anti-TNFα therapy. The transcriptional signature of responders was compared with that of non-responders after anti-TNFα therapy. Controls with non-inflammatory bowel disease (non-IBD) (n=17) were used for comparisons. Genes of interest were validated by real-time RT-PCR in an independent cohort of patients with CD receiving (n=17) or not (n=16) anti-TNFα and non-IBD controls (n=7). RESULTS: We confirmed that response to anti-TNFα is accompanied by significant regulation of a large number of genes, including IL1B, S100A8, CXCL1, which correlated with endoscopic activity. Remarkably, patients who failed to respond to anti-TNFα showed a mixed signature, maintaining increased expression of IL1B, IL17A and S100A8, while showing significant modulation of other genes commonly upregulated in active CD, including IL6 and IL23p19. CONCLUSIONS: Our results show that anti-TNFα therapy significantly downregulates a subset of inflammatory genes even in patients who fail to achieve endoscopic remission, suggesting that these genes may not be dominant in driving inflammation in non-responders. On the other hand, we identified IL1B and IL17A as genes that remained altered in non-responders, pointing to potentially more relevant targets for modulating mucosal damage in refractory patients.
Assuntos
Doença de Crohn/tratamento farmacológico , Fármacos Gastrointestinais/uso terapêutico , Mediadores da Inflamação/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adalimumab , Adulto , Idoso , Anti-Inflamatórios não Esteroides/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Colo/metabolismo , Doença de Crohn/genética , Doença de Crohn/metabolismo , Feminino , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Infliximab , Interleucina-6/biossíntese , Interleucina-6/genética , Mucosa Intestinal/metabolismo , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Ativação Transcricional , Falha de Tratamento , Adulto JovemRESUMO
It has been suggested that the R92Q mutation of the tumour necrosis factor receptor superfamily 1A (TNFRS1A) gene may be implicated in different inflammatory disorders. The aim of this study was to establish the role of this mutation as a determinant of Crohn`s disease (CD) susceptibility and/or clinical phenotype. One hundred and sixty-five CD patients and 203 healthy controls were prospectively included. The frequency of individuals carrying the R92Q mutation was similar between CD patients (4.24 percent) and controls (4.43 percent) (OR: 0.95; 95 percent CI = 0.34-2.62). In the genotype-phenotype evaluation, the univariate analysis showed that extra-intestinal manifestations were positively associated with the presence of R92Q mutation (p = 0.025; OR: 5.56; 95 percent CI = 1.04-29.6). In the multivariate analysis, presence of R92Q mutation was independently associated to extra-intestinal manifestations of CD, specially cutaneous manifestations (p = 0.02; OR: 5.17, 95 percent CI = 1.07-24.8). The R92Q mutation of TNFRSF1A gene is not a determinant of CD susceptibility, but contributes to the appearance of extra-intestinal manifestations of the disease.
Se ha sugerido que la mutación R92Q del gen de la super-familia del receptor del factor de necrosis tumoral 1A (TNFRS1A) podría estar relacionada con diversos trastornos inflamatorios. El objetivo de este estudio fue determinar el papel de esta mutación como factor determinante de la susceptibilidad y/o fenotipo clínico de la enfermedad de Crohn (EC). Ciento sesenta y cinco pacientes con EC y 203 controles sanos fueron incluidos de manera prospectiva. La frecuencia de individuos portadores de la mutación R92Q fue similar entre los pacientes con EC (4,24 por ciento) y los controles (4,43 por ciento) (OR: 0,95; 95 por ciento IC = 0,34-2,62). En la evaluación genotipo-fenotipo, el análisis univariado indicó que las manifestaciones extra-intestinales estaban relacionadas con la presencia de la mutación R92Q (p = 0,025; OR: 5,56; 95 por ciento IC = 1,04-29,6). En el análisis multivariado, la presencia de la mutación R92Q estuvo relacionada de manera independiente con las manifestaciones extra-intestinales de la EC, especialmente manifestaciones cutáneas (p = 0,02; OR: 5,17, 95 por ciento IC = 1,07-24,8). La mutación R92Q del gen TNFRSF1A no es un factor determinante de susceptibilidad a EC, pero contribuye a la aparición de manifestaciones extra-intestinales de la enfermedad.
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Doença de Crohn/complicações , Doença de Crohn/genética , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Doenças Inflamatórias Intestinais/genética , Dermatopatias/etiologia , Estudos de Casos e Controles , Seguimentos , Fenótipo , Genótipo , MutaçãoRESUMO
BACKGROUND: The main objective was to identify risk factors for extent progression in distal ulcerative colitis. The secondary objective was to determine clinical characteristics of disease at the time of progression. METHODS: Data were obtained from a prospective database. Distal colitis was defined as disease limited to rectum and sigmoid colon (n = 178), extensive colitis as involvement of at least the descending colon (n = 179), and colitis with progression when there was a change of category from distal to extensive (n = 63). To study clinical characteristics at the time of progression, a nested case-control study was performed. RESULTS: Compared to distal colitis, colitis with progression was associated to significantly higher prevalence of extraintestinal manifestations (42.9% versus 15.5%) steroid-refractory course (28.0% versus 2.2%), requirement of thiopurines (44.3% versus 17.3%), cyclosporine (25.4% versus 1.9%), infliximab (9.5% versus 1.2%), surgery (20.6% versus 0.6%), and incidence of neoplasia (6.3% versus 0%). However, these differences appeared after disease progression. Regression analysis demonstrated that preexisting independent predictive factors for progression were younger age at diagnosis (hazard ratio [HR] 0.979 95% confidence interval [CI] 0.959-0.999) and presence of sclerosing cholangitis (HR 12.83, 95% CI 1.36-121.10). The nested case-control study showed that at the time of progression the flare was more severe in cases than in matched controls, with significant differences in markers of disease severity, therapeutic requirements, hospitalizations, and surgery. CONCLUSIONS: Patients with distal ulcerative colitis diagnosed at a younger age or with associated sclerosing cholangitis are at higher risk for progression. Disease flare associated with progression follows a severe course with high therapeutic requirements.