Association between the level of circulating bioactive tumor necrosis factor alpha and the tumor necrosis factor alpha gene polymorphism at -308 in patients with rheumatoid arthritis treated with a tumor necrosis factor alpha inhibitor

OBJECTIVE: The tumor necrosis factor alpha (TNFalpha) -308A polymorphism has been associated with high production of TNFalpha and poor response to anti-TNFalpha therapy, but these associations remain controversial. The aim of this study was to explore the association between circulating TNFalpha bioactivity, the TNFalpha -308 polymorphism, and the clinical response to infliximab in patients with rheumatoid arthritis (RA). METHODS: One hundred ninety-eight patients with RA were treated with infliximab and methotrexate. Responses at 6 months according to the American College of Rheumatology (ACR) preliminary criteria for improvement in RA were recorded. Genotyping for the TNFalpha -308 polymorphism was performed by enzyme-linked oligosorbent assay. Circulating TNFalpha bioactivity was evaluated in 50 patients with RA by assessing the production of interleukin-6 (IL-6) in synoviocytes induced by a small amount of TNFalpha plus plasma. IL-6 production in 48-hour supernatants and the levels of TNFalpha protein and IL-6 were measured by enzyme-linked immunosorbent assay. RESULTS: The TNFalpha -308 polymorphism was not associated with the ACR response to infliximab. The level of circulating TNFalpha bioactivity was higher in patients with the TNFalpha -308 A/A or A/G genotype than that in patients with the G/G genotype (median 50.0 ng/ml [interquartile range (IQR) 31.5-62.0] versus 33.0 ng/ml [IQR 16.5-47.5]; P < 0.02). However, no difference was observed for the TNFalpha protein level according to genotype (median 0.62 pg/ml [IQR 0.00-8.85] for G/G versus 3.35 pg/ml [IQR 1.55-4.63] for A/A or A/G; P not significant). The level of circulating TNFalpha bioactivity was higher in good responders (> or =50% improvement) than in poor responders (< or =20% improvement) (median 45.0 ng/ml [IQR 21.0-59.0] versus 28.0 ng/ml [IQR 14.0-39.0]; P = 0.05). However, the level of TNFalpha protein was similar in both groups. CONCLUSION: The level of functional circulating TNFalpha is partially genetically determined and is predictive of the clinical response to infliximab. Nonresponders to anti-TNFalpha therapy are likely to have a disease that is not primarily driven by TNFalpha.     

Polymorphism at position -308 of the tumor necrosis factor alpha gene influences outcome of infliximab therapy in rheumatoid arthritis

OBJECTIVE: To test whether the G-to-A polymorphism at position -308 in the promoter of the tumor necrosis factor alpha (TNFalpha) gene influences response to infliximab therapy in patients with rheumatoid arthritis (RA). METHODS: We genotyped 59 RA patients by polymerase chain reaction and subdivided them into two groups: those with the A/A or A/G genotype and those with the G/G genotype. We compared the groups' clinical responses to infliximab treatment after 22 weeks, using the Disease Activity Score in 28 joints (DAS28). RESULTS: We found that 42% of patients in the A/A and A/G group and 81% of patients in the G/G group had improvement of at least 1.2 in the DAS28 score (P = 0.0086). The average improvement in the DAS28 score was 1.24 in the A/A and A/G patients and 2.29 in the G/G patients (P = 0.029). CONCLUSION: These data suggest that patients with a TNFalpha -308G/G genotype are better infliximab responders than are patients with A/A or A/G genotypes. TNFalpha -308 genotyping may be a useful tool for predicting response to infliximab treatment.     

Tumour necrosis factor (TNF)alpha -308 G/G promoter polymorphism and TNFalpha levels correlate with a better response to adalimumab in patients with rheumatoid arthritis

OBJECTIVE: To investigate the influence of -308 tumour necrosis factor-alpha (TNFalpha) promoter polymorphism and circulating TNFalpha levels in the clinical response to adalimumab treatment in patients with rheumatoid arthritis (RA). METHODS: Eighty-one patients with active RA were genotyped for the -308 TNFalpha polymorphism by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis and subdivided into two groups for each polymorphism (G/A and G/G genotype). All received 40 mg of adalimumab subcutaneously every other week. We compared the groups' clinical responses to adalimumab at 8, 16, and 24 weeks using the Disease Activity Score in 28 joints (DAS28). RESULTS: Both groups showed a significant improvement from baseline. A significant difference between groups was found at week 24. We found that 88.2% of G/G versus 68.4% of G/A for the -308 polymorphism were DAS28 responders (p = 0.05). The score improvement at week 24 was 2.5 +/- 1.3 in the G/G group and 1.8 +/- 1.3 in the G/A group for the -308 polymorphism (p = 0.04). The median of serum TNFalpha levels of the G/A group were lower than those of the G/G group, and statistically different at weeks 8 and 24 (p < 0.039 and p < 0.043). When comparing baseline levels to those achieved at 8, 16, and 24 weeks for the whole group, only responder patients showed a statistically significant overall increase in TNFalpha over time (p < 0.000001). CONCLUSION: A relationship between DAS28 improvement, the -308 G/G polymorphism, and increased circulating TNFalpha levels was found in Chilean RA patients treated with adalimumab.     

The -308 tumour necrosis factor-alpha gene polymorphism predicts therapeutic response to TNFalpha-blockers in rheumatoid arthritis and spondyloarthritis patients

OBJECTIVE: To examine whether the G-to-A polymorphism at position -308 in the promoter of the tumour necrosis factor-alpha (TNFalpha) gene influences the therapeutic response to TNFalpha-blockers in patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) and ankylosing spondylitis (AS). METHODS: A total of 54 patients with RA, 10 with PsA and 22 with AS were genotyped by polymerase chain reaction for the -308 TNFalpha promoter polymorphism. They were treated with infliximab (n = 63), adalimumab (n = 10) or etanercept (n = 13). Clinical response was assessed after 24 weeks by the Disease Activity Score in 28 joints (DAS28) for RA and PsA, and the Bath Ankylosing Spondylitis Activity Index (BASDAI) for AS patients. RESULTS: All patients with the A/A genotype (n = 3, all RA) and two patients with the A/G genotype (AS) failed to respond to anti-TNF treatment. Irrespective of the underlying disease, moderate response (n = 44) was predominantly associated with the A/G genotype (A/G 18/22, G/G 4/22), whereas good response (n = 59) was exclusively seen in patients with the G/G genotype. The average improvement in the DAS28 score was 0.83 in the A/A, 1.50 in the A/G and 2.64 in the G/G group of RA and PsA patients (P < 0.0001). The BASDAI score in AS improved on average by 1.21 in the A/G and by 3.30 in the G/G group (P < 0.005). CONCLUSIONS: The data suggest that humans with a TNFalpha -308 G/G genotype are better responders to anti-TNFalpha treatment than those with A/A or A/G genotypes independent of the treated rheumatic disease (RA, PsA or AS).     

Tumor necrosis factor-alpha promoter -308 A/G polymorphism and rheumatoid arthritis susceptibility: a metaanalysis

OBJECTIVE: Tumor necrosis factor-alpha (TNF-alpha) promoter -308 A/G polymorphism has been reported to be associated with rheumatoid arthritis (RA) with inconsistent results. We investigated whether TNF-alpha -308 A/G polymorphism confers susceptibility to RA. METHODS: We conducted a random effect metaanalysis on the association of genotypes A/A (recessive effect), A/A + A/G (dominant effect), A allele, and A/A vs G/G genotypes of the TNF-alpha -308 polymorphisms with RA overall and within different ethnic populations. RESULTS: Fourteen studies, 10 of Europeans, 3 of Latin Americans, and one Asian, were included in this metaanalysis. An association between RA and the TNF-alpha -308 A allele was not found in the overall population (OR 1.005, 95% CI 0.715-1.412, p = 0.976). However, stratification by ethnicity indicated that the TNF-alpha A allele was significantly associated with RA in Latin Americans (OR 2.004, 95% CI 1.158-3.467, p = 0.013). Conversely, there was no association detected for the TNF-alpha A allele with RA patients from the European samples (OR 0.911, 95% CI 0.684-1.212, p = 0.520). The OR for the A/A + A/G genotype, the A/A genotypes, and the A/A vs G/G genotypes in samples overall and in each ethnic group showed a similar trend to those for the TNF-alpha A allele. CONCLUSION: This metaanalysis demonstrates that the TNF-alpha -308 A/G polymorphism may represent a significant risk factor for RA in Latin Americans, but not in Europeans.     

Can tumor necrosis factor receptor II gene 676T>G polymorphism predict the response grading to anti-TNFα therapy in rheumatoid arthritis?

In this study we analyzed whether the polymorphisms 676T>G in the tumor necrosis factor receptor (TNFR) II gene and -308G>A in the TNFalpha promoter gene may influence the response grading to anti-TNFalpha therapy in rheumatoid arthritis. We enrolled and genotyped 105 RA patients treated with etanercept (n = 55), infliximab (n = 40) and adalimumab (n = 10) for 1 year. The clinical response was evaluated according to the ACR criteria every 3 months. Patients with TNFRII 676TG genotype was significantly associated with lower ACR response compared with 676TT genotype, at 3 (OR 3.78 95% CI 1.07-13.31) and 12 months (OR 4.30 95% CI 1.16-15.99) of treatment. No significant association between TNFalpha -308G>A polymorphism and the clinical response was found. TNFRII 676TG genotype is associated with a lower response to anti-TNFalpha therapy, independently from the specific agent used. This polymorphism could become a useful genetic marker for predicting the different response grading to anti-TNFalpha therapy.     

Polymorphism at position −308 of the tumor necrosis factor α gene influences outcome of infliximab therapy in rheumatoid arthritis

Objective

To test whether the G‐to‐A polymorphism at position −308 in the promoter of the tumor necrosis factor α (TNFα) gene influences response to infliximab therapy in patients with rheumatoid arthritis (RA).

Methods

We genotyped 59 RA patients by polymerase chain reaction and subdivided them into two groups: those with the A/A or A/G genotype and those with the G/G genotype. We compared the groups' clinical responses to infliximab treatment after 22 weeks, using the Disease Activity Score in 28 joints (DAS28).

Results

We found that 42% of patients in the A/A and A/G group and 81% of patients in the G/G group had improvement of at least 1.2 in the DAS28 score (P = 0.0086). The average improvement in the DAS28 score was 1.24 in the A/A and A/G patients and 2.29 in the G/G patients (P = 0.029).

Conclusion

These data suggest that patients with a TNFα −308G/G genotype are better infliximab responders than are patients with A/A or A/G genotypes. TNFα −308 genotyping may be a useful tool for predicting response to infliximab treatment.

     

Influence of -308 A/G polymorphism in the tumor necrosis factor alpha gene on etanercept treatment in rheumatoid arthritis

OBJECTIVE: To determine whether the -308 A/G tumor necrosis factor alpha (TNFalpha) gene polymorphism can predict the outcome of etanercept therapy in 86 patients with rheumatoid arthritis (RA), as already observed in patients treated with infliximab. METHODS: Eighty-six RA patients treated with etanercept were genotyped for -308 A/G TNFalpha gene polymorphism by polymerase chain reaction and melting curve analysis, using specific gene primers and probes. Patients were subdivided into group A (G/A genotype) and group G (G/G genotype). We compared clinical responses to etanercept between groups A and G after 6 months, using the Disease Activity Score in 28 joints (DAS28). After 12-month treatment, 48 of 86 patients were evaluated again. RESULTS: Of 86 patients, 18 (21%) belonged in group A and 68 (79%) belonged in group G. After 6-month treatment, 55.6% of patients in group A and 82.4% of patients in group G had DAS28 improvement >1.2 (P = 0.027 by chi-square). The mean +/- SD DAS28 improvement was 1.69 +/- 1.31 in group A and 2.23 +/- 1.19 in group G (P = 0.098 by t-test). After 1-year treatment 48 patients were tested again: 10 (21%) belonged in group A and 38 (79%) belonged in group G. Forty percent of patients in group A and 87% in group G had DAS28 improvement >1.2 (P = 0.005 by chi-square). The mean +/- SD DAS28 improvement was 1.334 +/- 1.37 in group A and 2.29 +/- 1.47 in group G (Mann-Whitney U test = 115, P = 0.0057). CONCLUSION: RA patients with a -308 G/G TNFalpha genotype respond to etanercept better than patients with a -308 A/G genotype.     

TNF-alpha -308A promoter polymorphism is associated with enhanced TNF-alpha production and inflammatory activity in Crohn's patients with fistulizing disease

OBJECTIVE: Tumor necrosis factor-alpha (TNF-alpha) plays a key role in the inflammatory response and pathogenesis of Crohn's disease (CD). TNF-alpha -308A polymorphism within the TNF-alpha gene promoter has been associated with enhanced TNF-alpha production in vitro. The aim of this study was to investigate the effect of TNF-alpha promoter polymorphism at -308 on the susceptibility and phenotypic expression of fistulizing CD. METHODS: The distribution of -308 TNF-alpha genotypes was analyzed in 50 patients with fistulizing CD and 100 healthy matched controls. TNF-alpha, interleukin-1beta, and interleukin-6 serum levels were measured by ELISA. Serum amyloid-A, C-reactive protein, alpha1-antitrypsin, alpha1-acid glycoprotein, and haptoglobin were measured by nephelometry. RESULTS: No significant differences were found in the allele frequencies of the polymorphism between patients and controls. However, compared with -308GG patients, those carrying -308AG had a significant increase of serum levels of TNF-alpha (58 +/- 79 vs 8 +/- 19 pg/ml, p < 0.001), interleukin-1beta (36 +/- 45 vs 16 +/- 20 pg/ml, p = 0.048), and acute phase proteins (APPs). -308A carriers had also a higher frequency of arthritis (66% vs 26%, p = 0.039). The logistic regression model showed that the patients carrying -308A polymorphism had a relative risk for developing arthritis of 5.45 (95% CI = 1.1-25.6). No other clinical or analytical findings were predictive for the risk of development of arthritis. CONCLUSIONS: TNF-alpha -308A polymorphism is associated with enhanced TNF-alpha production, more intense inflammatory activity, and an increased risk for arthritis susceptibility in CD patients with fistulizing disease.     

TNF-alpha -308 promoter polymorphism in patients with rheumatoid arthritis

OBJECTIVES: Rheumatoid arthritis (RA) is a chronic inflammatory disease in which tumour necrosis factor-alpha (TNF-alpha) plays an important role. There are, however, controversial reports that TNF-alpha promoter polymorphism may be an independent marker of susceptibility and severity of RA. The aim of the present study was to examine the TNF-alpha -308 promoter polymorphism in patients with RA. METHODS: We examined 91 patients with RA diagnosed according to the criteria of the American College of Rheumatology. Polymerase chain reaction (PCR) amplification was used for analysis of the polymorphism at position -308 in promoter of TNF-alpha gene. RESULTS: Distribution of TNF-alpha genotypes in RA patients did not differ from that in control subjects. Moreover, there was no association between TNF-alpha genotypes and age at disease diagnosis, disease activity in global physician's assessment, and joint and extra-articular involvement. There was also no correlation between TNF-alpha polymorphism and disease activity measures, including erythrocyte sedimentation rate (ESR), CRP, number of swollen and tender joints, and morning stiffness duration. CONCLUSIONS: We suggest that TNF-alpha -308 promoter polymorphism is not a genetic risk factor for RA susceptibility and severity.     

Tumor necrosis factor-alpha and Interleukin-10 gene promoter polymorphisms in Turkish rheumatoid arthritis patients

Tumor necrosis factor and interleukin 10 have been implicated in the pathogenesis of rheumatoid arthritis (RA). Certain single-nucleotide polymorphisms (SNPs) within the promoter region of the IL-10 and TNF genes have been associated with altered levels of circulating IL10 and TNF. We aimed to explore the association of IL-10 and TNF-alpha polymorphisms in Turkish RA patients. We analyzed the association of TNF-alpha (-308G/A, -238G/A, -376G/A) and IL10 (-1082G/A, -819C/T, -592C/A) polymorphisms in 98 Turkish patients with rheumatoid arthritis and 122 healthy subjects using ARMS-PCR. The correlation of these findings with RF positivity and erosive disease in RA patients was also sought. A significant association was found between having RA and -1082 G allele (p = 0.008; OR = 1.44, 95% CI 1.11-1.86). There was no association between RA and -819C/T polymorphism. Significant differences were observed in IL10 GCC and ACC haplotypes distribution between RA and control subjects (p = 0.006; OR = 1.46, 95% CI 1.13-1.89 and p = 0.011; OR = 1.43, 95% CI 1.09-1.88, respectively). No statistically significant association was found between TNF-alpha 308G/A, -238G/A, -376G/A polymorphisms and RA. No significant association was found between RF positivity and erosive disease and TNF-alpha, IL10 gene polymorphisms. In addition, when combined genotypes were analyzed, no significant difference was found between RA patients and healthy controls. Our findings suggest that IL-10 1082 G/A polymorphism or GCC, ACC haplotypes may be associated with RA in Turkish patients.     

Response to combination therapy with interferon alfa-2a and ribavirin in chronic hepatitis C according to a TNF-alpha promoter polymorphism

BACKGROUND: Tumor necrosis factor-alpha (TNF-alpha) is involved in the pathogenesis of chronic active hepatitis C. Polymorphisms in the promoter region of the TNF-alpha gene can alter the TNF-alpha expression and modify the host immune response. The present study aimed at the correlation of the G308A TNF-alpha polymorphism with the response to antiviral combination therapy in chronic hepatitis C. PATIENTS AND METHODS: 62 patients with HCV and 119 healthy unrelated controls were genotyped for the G308A TNF-alpha promoter polymorphism. The patients received 3 x 3 million units of interferon alfa-2a and 1,000-1,200 mg ribavirin daily according to their body weight. A response was defined as absence of HCV-RNA and normalization of S-ALT after 6 months of combination therapy. RESULTS: With respect to the allele and genotype frequency, a significant difference was not observed between controls and patients with chronic hepatitis C. Furthermore, such a difference was also not observed if responders and non-responders to antiviral therapy were compared. CONCLUSIONS: The promoter polymorphism of the TNF-alpha gene investigated herein is equally distributed in healthy individuals and patients with hepatitis C and does not seem to predict the response to therapy with interferon alfa-2a and ribavirin.     

Association of TNF-alpha -308 G/A and IL-4 -589 C/T gene promoter polymorphisms with asthma susceptibility in the south of Iran.

BACKGROUND: Both tumor necrosis factor alpha (TNF-alpha) and interleukin (IL) 4 have been implicated in the pathogenesis of asthma. Furthermore, a G/A substitution at position -308 of the TNF-alpha gene promoter and a C/T substitution at position -589 of the IL-4 gene promoter have been associated with increased production of TNF-alpha and IL-4, respectively. OBJECTIVE: The aim of the present study was to analyze the association between TNF-alpha-308 G/A and IL-4-589 C/T polymorphisms and susceptibility to asthma in a group of patients from southern Iran. METHODS: We analyzed the frequency of TNF-alpha -308 G/A and IL-4-589 C/T polymorphisms in a total of 203 asthmatic patients compared to 113 nonasthmatic control subjects. RESULTS: An association was observed between the TNF-alpha -308 G/A polymorphism and susceptibility to asthma in patients with a ratio between forced expiratory volume in 1 second and forced vital capacity of less than 75% compared with normal subjects; however, the association did not achieve statistical significance (P = .054). The IL-4-589 C/T polymorphism was associated with asthma susceptibility (P = .02). In addition, the association between this polymorphism and asthma severity approached statistical significance (P = .07). CONCLUSION: These results provide further evidence for a role of TNF-alpha-308 G/A and IL-4-589 C/T polymorphisms in susceptibility to and severity of asthma. Further studies involving a larger number of patients may help to confirm our observations.     

Fcgamma receptor type IIIA genotype and response to tumor necrosis factor alpha-blocking agents in patients with rheumatoid arthritis

OBJECTIVE: To determine whether a functional single-nucleotide polymorphism in the gene encoding Fcgamma receptor type IIIA (FcgammaRIIIA) correlates with the response to treatment with tumor necrosis factor alpha inhibitors in rheumatoid arthritis (RA). METHODS: The study population comprised 282 Swedish patients with RA in whom the therapeutic efficacy of conventional disease-modifying antirheumatic drugs had been insufficient. Infliximab or etanercept treatment was initiated, and patients were evaluated after 3 months, using the American College of Rheumatology 20% improvement criteria (ACR20), the ACR50, and the ACR70 or the European League Against Rheumatism (EULAR) criteria. The chi-square test was used to compare response rates across FcgammaRIIIA genotypes. RESULTS: No differences in genotype distribution were observed among nonresponders compared with ACR20 responders (P = 0.80), ACR50 responders (P = 0.56), or ACR70 responders (P = 0.91). Similar results were observed when analyzing infliximab and etanercept separately or when using the EULAR response criteria. CONCLUSION: Unlike the findings of a previous study, the results of the current study suggest that the 158V/F polymorphism of FcgammaRIIIA is very unlikely to influence the clinical efficacy of infliximab or etanercept in patients with RA.     

Lack of association of tumor necrosis factor alpha gene polymorphism in patients with rheumatoid arthritis in central Taiwan

The aim of this study was to investigate the association of tumor necrosis factor alpha (TNFalpha) gene promoter polymorphisms in Chinese patients with rheumatoid arthritis (RA) in central Taiwan. A total of 106 RA patients and 253 normal controls were studied. Polymerase chain reaction (PCR)-based restriction analysis was used to identify A/G polymorphism at position 308 in the promoter region of the TNFalpha, which is located at 6q21.3. For the genotype of TNFalpha-308 polymorphism, there was no statistically significant difference between RA patients and normal controls (Fisher's exact test, P=0.82). Additionally, no statistical association in the distribution of TNFalpha-308 polymorphism between rheumatoid factor (RF)-positive and -negative patients was noted. The lack of an association of TNFalpha-308 polymorphism with RA and RF in our study implies that TNFalpha-308 polymorphism cannot serve as a candidate gene marker for screening RA patients in Taiwan.     

TNF-alpha promoter region gene polymorphisms in HIV-positive patients with lipodystrophy

OBJECTIVE: The pathogenic mechanisms underlying lipodystrophy in HIV-positive patients are largely unknown. TNF-alpha has many actions that are consistent with the features of lipodystrophy; therefore, an analysis was carried out to determine whether functionally active polymorphisms in the promoter region of the TNF-alpha gene are associated with the development of lipodystrophy. DESIGN: Genetic case-control association study. METHODS: Individuals were genotyped for the -238 and -308 polymorphisms in the TNF-alpha gene using polymerase chain reaction-restriction fragment length polymorphism analysis. The genotype and allele frequencies for 61 HIV-positive patients with lipodystrophy were compared with (a) 35 HIV-positive patients with no evidence of lipodystrophy and (b) 239 healthy HIV-negative individuals. RESULTS: The frequency of the variant rare -238 allele was significantly different (P = 0.01) in HIV-positive patients with lipodystrophy than in those without lipodystrophy. At the genotype level, a trend towards a difference between patients with and without lipodystrophy was observed (chi2 for linear trend 5.2, P = 0.02). For the -308 polymorphism, no difference was found in genotype and allele frequencies between HIV patients with and without lipodystrophy. CONCLUSIONS: The data suggest that the -238 (but not the -308) promoter region TNF-alpha gene polymorphism is a determinant in the development of HIV-related lipodystrophy. However, the results need to be confirmed in larger numbers of patients as well as in an ethnically diverse population.     

Tumor necrosis factor alpha, its soluble receptor I, and -308 gene promoter polymorphism in patients with rheumatoid arthritis with or without amyloidosis: implications for the pathogenesis of nephropathy and anemia of chronic disease in reactive amyloidosis

OBJECTIVE: To study tumor necrosis factor alpha (TNFalpha) -308 gene promoter polymorphism and circulating levels of TNFalpha and soluble TNF receptor type I (sTNFRI) in rheumatoid arthritis (RA) patients with and without reactive amyloidosis. METHODS: In a retrospective study, we examined 55 RA patients with biopsy-proven reactive amyloidosis and 55 control RA patients without amyloidosis (matched for age, sex, rheumatoid factor titer, and RA duration). Inflammatory activity was assessed by measuring the erythrocyte sedimentation rate and C-reactive protein level. TNFalpha gene promoter polymorphism was studied using polymerase chain reaction-restriction fragment length polymorphism assay. Cytokine and receptor levels were measured by enzyme-linked immunoassays. RESULTS: Patients with RA and amyloidosis had significantly higher TNFalpha and sTNFRI levels than did the control RA patients. The increased circulating levels of TNFalpha correlated with interleukin-18 levels, but not with the serum amyloid A protein levels or with TNFalpha -308 gene promoter polymorphism (reported to be associated with high TNFalpha levels and certain disease susceptibilities). In the patients with RA and amyloidosis, those with anemia had significantly higher TNFalpha and sTNFRI levels than did those without anemia, and circulating TNFalpha and sTNFRI levels correlated negatively with hemoglobin concentrations. In the patients with RA and amyloidosis, those with nephropathy had significantly higher TNFalpha and sTNFRI levels than did those without nephropathy; in patients with isolated proteinuria (but no creatinine elevation) the TNFalpha level was also significantly increased, indicating that the TNFalpha elevation was not merely a consequence of impaired renal function. CONCLUSION: This study shows that circulating levels of TNFalpha and sTNFRI are significantly increased in RA patients with amyloidosis as compared with control RA patients without amyloidosis and that the increased levels may be implicated in the pathogenesis of certain disease manifestations, including anemia of chronic disease and renal pathology in reactive amyloidosis.     

A positive response to infliximab in Crohn disease: association with a higher systemic inflammation before treatment but not with -308 TNF gene polymorphism

BACKGROUND: Two-thirds to three-fourths of patients with either refractory luminal or fistulizing Crohn disease respond to infliximab treatment. The ability or inability to respond seems to persist over time. Biological characteristics and/or genetic background can influence the response to treatment. The aim was to assess the value of C-reactive protein and TNF-alpha serum levels before treatment as well as the TNF -308 gene polymorphism in the prediction of response to infliximab treatment in Crohn disease. METHODS: Two-hundred-and-twenty-six Crohn disease patients treated in the setting of an expanded access programme to infliximab in Belgium were studied. There were 136 refractory luminal diseases and 90 refractory fistulizing diseases. Luminal diseases were treated with one single infusion; fistulizing diseases with three infusions at weeks 0, 2 and 6. A clinical response to treatment was defined as either a Crohn disease activity index <150 (complete) or a drop of 70 points (partial) at week 4, for luminal disease, and as either complete fistula healing (complete) or a decrease of at least 50% of the number of draining fistulas on two consecutive visits between weeks 0 and 18, for fistulizing disease. CRP and serum TNF-alpha levels were measured at week 0 before treatment and were compared between responders and non-responders. Patients were genotyped for the -308 TNF gene polymorphism, and allelic as well as genotype frequencies were compared between responders and non-responders. RESULTS: There were 73.2% responders (46.4% complete and 26.8% partial) and 26.8% non-responders. Response rates were similar in luminal and fistulizing diseases. CRP level before treatment was significantly higher in responders than in non-responders (16.8 mg/l (5-160) versus 9.6 mg/l (5-143); P = 0.02). Furthermore, response rate was significantly higher in patients with elevated CRP (>5 mg/l) than in patients with a normal CRP value (<5 mg/l) before treatment (76% versus 46%; P=0.004; OR: 0.26 (0.11-0.63)). Allelic and genotype frequencies for -308 TNF gene polymorphism were not significantly different between responders and non-responders--with the exception of a slightly higher TNF2 frequency in non-responders in luminal disease (22.1 % versus 11.6%; P = 0.04). However, this was not associated with a significant difference in genotype frequencies. CONCLUSION: A positive clinical response to infliximab was associated with a higher CRP level before treatment in our population of Crohn disease patients, but there was no relevant association with -308 TNF gene polymorphism. We therefore suggest that CRP level may help to identify better candidates for infliximab treatment.     

Association between tumor necrosis factor-α (TNF-α) promoter −308 G/A and response to TNF-α blockers in rheumatoid arthritis: a meta-analysis

Abstract

Objectives Tumor necrosis factor (TNF)-α promoter ?308G/A polymorphism has been shown to be associated with high TNF-α production and poor response to anti-TNF-α treatment. However, not all patients show a good response to TNF-α antagonists, so this association remains controversial. This study was designed to investigate whether TNF-α promoter ?308 G/A polymorphism is associated with responsiveness to anti-TNF therapy in rheumatoid arthritis (RA) patients. The 28-joint count Disease Activity Score (DAS) 28 or the American College of Rheumatology (ACR) improvement criteria 20 were used to measure patient response.

Methods A meta-analysis was performed. Pooled ORs and 95 % CIs were calculated by both dominant and recessive genetic models.

Results Fifteen studies with a total of 2127 patients were included in this meta-analysis. The results showed that patients with the G allele responded better to the treatment (OR = 1.87, 95 % CI 1.26–2.79). A subanalysis showed similar results.

Conclusions Based on the results of this meta-analysis, RA patients with the TNF-α promoter ?308 G allele respond better to TNF-α antagonist treatment, suggesting that this allele plays a major role in anti-TNF-alpha treatment response.     

Influence of −308 A/G polymorphism in the tumor necrosis factor α gene on etanercept treatment in rheumatoid arthritis

Objective

To determine whether the ?308 A/G tumor necrosis factor α (TNFα) gene polymorphism can predict the outcome of etanercept therapy in 86 patients with rheumatoid arthritis (RA), as already observed in patients treated with infliximab.

Methods

Eighty‐six RA patients treated with etanercept were genotyped for ?308 A/G TNFα gene polymorphism by polymerase chain reaction and melting curve analysis, using specific gene primers and probes. Patients were subdivided into group A (G/A genotype) and group G (G/G genotype). We compared clinical responses to etanercept between groups A and G after 6 months, using the Disease Activity Score in 28 joints (DAS28). After 12‐month treatment, 48 of 86 patients were evaluated again.

Results

Of 86 patients, 18 (21%) belonged in group A and 68 (79%) belonged in group G. After 6‐month treatment, 55.6% of patients in group A and 82.4% of patients in group G had DAS28 improvement >1.2 (P = 0.027 by chi‐square). The mean ± SD DAS28 improvement was 1.69 ± 1.31 in group A and 2.23 ± 1.19 in group G (P = 0.098 by t‐test). After 1‐year treatment 48 patients were tested again: 10 (21%) belonged in group A and 38 (79%) belonged in group G. Forty percent of patients in group A and 87% in group G had DAS28 improvement >1.2 (P = 0.005 by chi‐square). The mean ± SD DAS28 improvement was 1.334 ± 1.37 in group A and 2.29 ± 1.47 in group G (Mann‐Whitney U test = 115, P = 0.0057).

Conclusion

RA patients with a ?308 G/G TNFα genotype respond to etanercept better than patients with a ?308 A/G genotype.