Overexpression in Sjögren's Syndrome Patients May Be Regulated by rs4932178 SNP in Its Promoter Region and Correlates with Gene Expression.

Background: The gene encodes for the protease enzyme Furin, which promotes proteolytic maturation of important regulators of the immune response, and also enhances the secretion of interferon-γ (IFN). Several studies have suggested its possible involvement in the pathogenesis of chronic inflammatory diseases.

Methods: We investigated the gene expression level in peripheral blood mononuclear cells isolated from Sjögren's Syndrome (SS) patients and healthy controls and we evaluated a possible correlation with gene expression. Moreover, we also explored the variability of two genetic polymorphisms (rs4932178 and rs4702) to evaluate a possible association between these polymorphisms and the expression levels of this gene.

Results: We observed, by RT-qPCR, that the expression level was significantly higher in SS patients compared to the controls ( = 0.028), and we confirmed a positive correlation between and expression levels ( < 0.001). Moreover, we reported that the variant homozygous genotype of rs4932178 SNP is associated with a higher expression of the gene ( = 0.038) and with the SS susceptibility ( = 0.016).

Conclusions: Our data suggest that Furin could play a role in SS development, also promoting IFN-γ secretion.