ABSTRACT
Tumor necrosis factor α (TNFα) may contribute to the pathologic process of congestive heart failure (CHF). TNFα signaling occurs through two receptors; TNFR1 (TNFRSF1A) and TNFRII (TNFRSF1B). In humans a single nucleotide polymorphism (rs1061622 in TNFRSF1B exon 6; T587G) encodes two different amino acids (M196R) in the transmembrane region. The 587G allele is associated with greater severity and/or prevalence of some inflammatory diseases, but its role in CHF in unknown. This study sought to test the hypothesis that the 587G allele is associated with a worse outcome or more severe phenotype in CHF. Peripheral blood DNA was isolated and genotyped from 379 heart failure patients enrolled in a genetic outcome study (GRACE); (44.7% ischemic, 70.4% male, 8.5% black race, age 55.6 ± 11.7 yr (SD), LVEF 24.5 ± 8.3%, NYHA 2.53 ± 0.64). Genotyping was performed by PCR-RFLP. Cardiac function was assessed from medical records at study entry. The distribution of genotypes in this population was 54% T/T, 38.4% G/T and 7.7% G/G. Mean LV ejection fraction (T/T 24.4 ± 8.2, T/G 25.0 ± 8.4, G/G 23.3 ± 8.6, n=352, p=ns) and LV end-diastolic dimensions (T/T 6.57 ± 0.93, T/G 6.53 ± 1.0, G/G 6.57 ± 0.78, n=211, p=ns) were comparable in all groups. Transplant-free survival (median 23 months (range 1-62 months) did not vary by genotype (p=0.95). A lack of effect (p=0.74) on transplant-free survival was also observed in a subset of patients with ischemic heart failure (n=169). The TNFRSF1B 587G allele is not associated with the severity of heart failure phenotype or clinical outcomes in patients with chronic CHF.
Subject(s)
Heart Failure/genetics , Heart Failure/therapy , Receptors, Tumor Necrosis Factor, Type II/genetics , Alleles , Amino Acid Substitution , Base Sequence , Female , Genetic Predisposition to Disease , Genotype , Humans , Male , Middle Aged , Polymorphism, Single Nucleotide , Sequence Analysis, DNA , Treatment Outcome , Tumor Necrosis Factor-alpha/geneticsABSTRACT
HYPOTHESIS: Adenoviral-mediated (AdV-T2) overexpression of TIMP-2 would blunt ventricular remodeling and improve survival in a murine model of chronic ischemic injury. METHODS: Male mice (n = 124) aged 10-14 weeks underwent either (1) left coronary artery ligation to induce myocardial infarction (MI group, n = 36), (2) myocardial injection of 6 × 10¹° viral particles of AdV-T2 immediately post-MI (MI + T2 group, n = 30), (3) myocardial injection of 6 × 10¹° viral particles of a control adenovirus (MI + Ct, n = 38), or 4) received no intervention (controls, n = 20). On post-MI day 7, surviving mice (n = 79) underwent echocardiographic, immunohistochemical, and biochemical analysis. RESULTS: In infarcted animals, the MI + T2 group demonstrated improved survival (p < 0.02), better preservation of developed pressure and ventricular diameter (p < 0.04), and the lowest expression and activity of MMP-2 and MMP-9 (p < 0.04) compared with MI and MI + Ct groups. All infarcted hearts displayed significantly increased inflammatory cell infiltration (p < 0.04 vs. control, MI, or MI + T2), with infiltration highest in the MI + Ct group and lowest in the MI + T2 group (p < 0.04). CONCLUSIONS: Adenoviral mediated myocardial delivery of the TIMP-2 gene improves post-MI survival and limits adverse remodeling in a murine model of MI.
Subject(s)
Gene Transfer Techniques , Genetic Therapy , Myocardial Infarction/physiopathology , Myocardial Infarction/therapy , Tissue Inhibitor of Metalloproteinase-2/genetics , Tissue Inhibitor of Metalloproteinase-2/therapeutic use , Ventricular Remodeling/physiology , Animals , Blotting, Western , Cardiomegaly/etiology , Cardiomegaly/pathology , Cardiomegaly/physiopathology , Collagen/metabolism , Dilatation , Immunohistochemistry , Male , Matrix Metalloproteinases/metabolism , Mice , Mice, Inbred C57BL , Myocardial Infarction/complications , Myocardium/enzymology , Myocardium/pathology , Survival AnalysisABSTRACT
Alterations in DNA mismatch repair (MMR) proteins result in microsatellite instability (MSI), increased mutation accumulation at target genes and cancer development. About one-third of gastric cancers display high-level microsatellite instability (MSI-High) and low-level microsatellite instability (MSI-Low) is frequently detected. To determine whether variations in the levels of MMR proteins or mutations in the main DNA MMR genes are associated with MSI-Low and MSI-High in gastric cancer cell lines, the MSI status (MSI-High, MSI-Low or MS-Stable (MSS)) of 14 gastric cancer lines was determined using multiple clone analysis with a panel of five microsatellite markers. Protein levels of hMLH1, hMSH2, hMSH6, hPMS2 and hPMS1 were determined by Western blot. Sequence analysis of hMLH1 and hMSH2 was performed and the methylation status of the hMLH1 promoter was examined. The cell lines SNU1 and SNU638 showed MSI-High, decreased to essentially absent hMLH1 and hPMS2 and reduced hPMS1 and hMSH6 protein levels. The hMLH1 promoter region was hypermethylated in SNU638 cells. The MKN28, MKN87, KATOIII and SNU601 cell lines showed MSI-Low. The MMR protein levels of cells with MSI-Low status was similar to the levels detected in MSS cells. A marked decrease in the expression levels of MutL MMR proteins (hMLH1, hPMS2 and hPMS1) is associated with high levels of MSI mutations in gastric cancer cells. Gastric cancer cell lines with MSI-Low status do not show significant changes in the levels of the main DNA MMR proteins or mutations in the DNA mismatch repair genes hMSH2 and hMLH1. These well-characterized gastric cancer cell lines are a valuable resource to further our understanding of DNA MMR deficiency in cancer development, progression and prognosis.
