Reduced gene expression of Survivin in PBMCs from patients with limited systemic sclerosis

Systemic sclerosis (SSc) is a rheumatologic disease, and fibroblasts are the main cells responsible for SSc pathogenesis. The BIRC5 gene encodes survivin, an inhibitor of apoptosis protein. Studies have suggested a role for survivin overexpression in leading to decreased apoptosis of fibroblasts in SSc patients. This study explored the frequencies of two single nucleotide polymorphisms (SNPs) in the BIRC5 gene (rs9904341 [G>C] and rs17878467 [C>T]) in SSc patients and evaluated survivin gene expression in the peripheral blood mononuclear cells (PBMC) of patients and compared it with that of healthy individuals. The allelic and genotypic frequencies of rs9904341 in 459 SSc patients and 487 healthy controls were assessed. For the rs17878467 SNP, the survivin gene in 214 SSc patients and 246 controls was analyzed. Genomic analyses were carried out on DNA samples isolated from whole blood by the phenol-chloroform method. TaqMan rt-PCR was used to investigate the survivin gene alleles. Survivin gene expression was also investigated in 53 patients (lSSc = 25, dSSc = 28) and 55 controls by specific primers for the survivin gene (SYBR Green Real-time PCR method). The allelic and genotypic frequencies of both SNPs showed no significant difference in patients and controls; however, survivin expression level was significantly lower in limited SSc (lSSc) and total SSc patients than in controls. The results suggest that survivin might have a role in the pathogenesis of SSc; however, more research is needed to confirm the relationship.