RESUMO
BACKGROUND: The aim of the present study was to evaluate the methylation pattern in the suppressor of cytokine signaling 1 (SOCS1) gene in smokers and non-smokers with chronic periodontitis (CP). METHODS: Methylation-specific polymerase chain reaction (PCR) was performed to determine the methylation status of the SOCS1 promoter in 45 saliva samples from smokers and non-smokers with CP. RESULTS: Cells from the saliva of CP patients who smoked were 7.08 times more likely to have a methylated SOCS1 promoter than cells from the saliva of non-smoking patients. CONCLUSIONS: SOCS1 gene promoter methylation, with its potential effects on the expression of this gene, seems to be a consequence of exposure to tobacco and not to periodontal disease. Further studies are needed to elucidate the relationship between the epigenetic control of immune response gene expression, exposure to environmental factors, and the development, progression, and prognosis of CP.
Assuntos
Periodontite Crônica , Metilação de DNA , Células Epiteliais , Humanos , Regiões Promotoras Genéticas , Saliva , Proteína 1 Supressora da Sinalização de CitocinaRESUMO
Tumor suppressor gene promoter CpG island methylation is a well-recognized mechanism in cancer pathogenesis, but its role in multiple myeloma (MM) is controversial. The present study investigated the methylation status and expression of P16, suppressor of cytokine signaling 1 (SOCS-1), P73, E-cadherin and Src homology region 2 domain-containing phosphatase 1 (SHP-1), as well as global methylation in patients with MM during active disease and remission. Bone marrow samples were obtained from 43 patients at the Multiple Myeloma Clinic, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán (Mexico City, Mexico) during active disease and remission. Methylation-specific polymerase chain reaction and ELISA were performed on bisulfite-treated or untreated DNA to determine promoter-specific or genomic methylation, respectively. Gene expression was measured using reverse-transcription polymerase chain reaction. The results indicated that SOCS-1 methylation occurred more frequently during active disease than remission [29 vs. 3.2% (P=0.021)] and was associated with more advanced forms of the disease [international staging system (ISS) 3, 16.67% vs. ISS 1, 8.3% (P=0.037)]. SHP-1 methylation during active disease was associated with a lower probability of survival at 39-month follow up (median), 52.5 vs. 87.5% (P=0.025). The percentage of methylation was associated with active disease at remission, but this was not significant. Global hypomethylation at remission was a negative predictor factor for overall survival (OS). The results indicated that methylated P16, SOCS-1 and SHP-1 were associated with clinical variables of poor prognosis in MM, likewise the persistence of global hypomethylation at remission. The negative impact on OS of global hypomethylation at remission must be confirmed in a larger sample. Future studies are necessary to investigate whether patients with global hypermethylation at remission should receive more aggressive treatments to improve their OS.
RESUMO
Recent studies provide evidence on the emerging role of the SOCS1 gene in the development and progression of atherosclerotic lesions. This gene encodes for the suppressor of the cytokine signaling-1 protein that interacts directly with the Janus kinases that are essential intracellular mediators of the immune cytokine action. The aim of this study was to test for associations between SOCS1 gene single nucleotide polymorphisms (SNPs) and the risk of developing acute coronary syndromes (ACS) in a group of Mexicans patients. Four SNPs [-3969 C>T (rs243327), -1656 G>A (rs243330), -820 G>T (rs33977706) and +1125 G>C (rs33932899)] of SOCS1 gene were determined for TaqMan genotyping assays in a group of 447 patients with ACS and 622 healthy controls. Under heterozygous model, the -3969 C>T (rs243327) SNP was associated with increased risk of ACS (OR=1.45, P(Het)=0.021). On the other hand, under co-dominant and heterozygous models, the -1656 G/A (rs243330) SNP was associated with increased risk of ACS (OR=1.47, P(Co-dom)=0.038 and OR=1.50, P(Het)=0.013, respectively). Moreover, under co-dominant, dominant, and heterozygous models, the -820T/G (rs33977706) SNP was associated with increased risk of ACS (OR=1.59, P(Co-dom)=0.03, OR=1.48, P(Dom)=0.028 and OR=1.61, P(Het)=0.01). Finally, under co-dominant and heterozygous models, the +1125 G/C (rs33932899) SNP was associated with increased risk of ACS (OR=1.54, P(Co-dom)=0.006, OR=1.58, P(Het)=0.012, respectively). Models were adjusted for gender, age, body index mass, dyslipidemia, alcohol consumption, and smoking. In summary, our data suggests that the four studied polymorphisms of the SOCS1 gene play an important role as susceptibility markers for developing ACS.