Serum IL-17 and TNFα as prognostic biomarkers in systemic sclerosis patients: a prospective study.

Recent reports have demonstrated that endothelial injury is critical in the pathogenesis of systemic sclerosis (SSc) and is associated with increased levels of circulating inflammatory biomarkers. This study aims to analyze the serum concentrations of selected cytokines and evaluate their relationship with SSc clinics and the long-term course of the disease. This study included 43 SSc patients and 24 matched healthy controls. In both groups, we measured serum levels of inflammatory cytokines related to the inflammatory response, such as tumor necrosis factor (TNF)α, interferon (IFN)γ, interleukin (IL)-4, IL-6, IL-10, and IL-17, and fibroblast activation protein (FAP). Additionally, in SSc patients, we evaluated the presence of four single nucleotide polymorphisms (SNPs) located in the promotor region of the TNFA gene, namely rs361525, rs1800629, rs1799964, and rs1799724, which might be related to increased TNFα concentrations. The main aim consisted of associating inflammatory cytokines with (1) clinical disease characteristics and (2) longitudinal observation of survival and cancer prevalence. SSc patients were characterized by a 17% increase in serum TNFα. There was no other difference in serum cytokines between the studied groups and diffuse vs. limited SSc patients. As expected, evaluated serum cytokines correlated with inflammatory biomarkers (e.g., IL-6 and C-reactive protein). Interestingly, patients with higher IL-17 had decreased left ventricle ejection fraction. During the median 5-year follow-up, we recorded four cases of neoplastic diseases (lung cancer in two cases, squamous cell carcinoma of unknown origin, and breast cancer with concomitant multiple myeloma) and nine deaths. The causes of death included lung cancer (n = 2), renal crisis (n = 1), multiple-organ failure (n = 1), and unknown reasons in five cases. Surprisingly, higher TNFα was associated with an increased cancer prevalence, while elevated IL-17 with death risk in the follow-up. Furthermore, the AG rs361525 genotype referred to higher TNFα levels than GG carriers. Both AG rs361525 and CT rs1799964 genotypes were associated with increased cancer risk. Higher serum concentrations of TNFα characterize the SSc patients, with the highest values associated with cancer. On the other hand, increased IL-17 in peripheral blood might predict poor SSc prognosis. Further research is needed to validate these findings.

Association between clinical features and course of systemic sclerosis and serum interleukin-8, vascular endothelial growth factor, basic fibroblast growth factor, and interferon alpha.

BACKGROUND: Certain mediators, such as soluble growth factors and cytokines, among others, are implicated in the immunopathogenesis of systemic sclerosis (SSc). OBJECTIVES: This study aimed to examine the association between serum levels of vascular endothelial growth factor (VEGF), interleukin-8 (IL-8), interferon alpha (IFN-α), and basic fibroblast growth factor (bFGF) and the clinical presentation and course of SSc. MATERIAL AND METHODS: This longitudinal, observational study included 43 patients with SSc and 24 healthy subjects. Serum concentrations of VEGF, IL-8, IFN-α, and bFGF were measured at baseline in patients previously treated for SSc. Medical history of patients was analyzed retrospectively at the time of cytokine measurement to infer clinical correlations, and during follow-up for a median of 5 years, assessing the incidence of death or cancer. RESULTS: The bFGF and IFN-α concentrations differed between SSc patients and controls (p < 0.01). In turn, organ involvement and SSc phenotypes did not impact studied cytokine concentrations, similar to systemic steroid and/or immunosuppressant use at enrollment. However, we have documented a positive correlation between the current oral steroid dose and serum levels of IL-8 and bFGF. Furthermore, patients with a VEGF level ≥95.7 pg/mL and IFN-α level ≥3.6 pg/mL required cyclophosphamide therapy more often, currently or in the past (approx. 3-fold and 4-fold, respectively). Substantially elevated VEGF and IFN-α concentrations at baseline were associated with higher cancer occurrence (n = 4) during follow-up, while elevated circulating IL-8 level was associated with an increased risk of death (n = 9). CONCLUSIONS: The SSc group was characterized by higher serum concentrations of bFGF and IFN-α compared to healthy controls. Patients treated with cyclophosphamide or receiving higher systemic steroid doses, thus suffering from a more severe disease type, had increased cytokine levels. Elevated circulating IFN-α and VEGF levels might be correlated with cancer, whereas raised IL-8 levels may be associated with an increased risk of death. However, further research is needed to verify our findings.

Genetic Association between TNFA Polymorphisms (rs1799964 and rs361525) and Susceptibility to Cancer in Systemic Sclerosis.

Tumor necrosis factor (TNF)-α is a proinflammatory cytokine that plays an important role in the pathogenesis of autoimmune diseases. The aim of the study was to establish an association between TNF-α promoter variability and systemic sclerosis (SSc). The study included 43 SSc patients and 74 controls. Four single nucleotide polymorphisms (rs361525, rs1800629, rs1799724, and rs1799964) located at the promoter of the TNFA gene were genotyped using commercially available TaqMan allelic discrimination assays with real-time PCR. The rs1799724 allele was associated with an increased SSc susceptibility (p = 0.028). In turn, none of the polymorphisms studied were related to the clinical and laboratory parameters of SSc patients, except for a higher prevalence of anti-Ro52 antibodies in the AG rs1800629 genotype in comparison to GG carriers (p = 0.04). Three of four cancer patients had both CT rs1799964 and AG rs361525 genotypes; thus, both of them were related to the increased risk of cancer, as compared to the TT (p = 0.03) and GG carriers (p = 0.0003), respectively. The TNFA C rs1799724 variant is associated with an increased risk of SSc, while the CT rs1799964 and AG rs361525 genotypes might enhance cancer susceptibility in SSc patients, although large observational and experimental studies are needed to verify the above hypothesis.