Tumor necrosis factor-stimulated gene-6-a new serum identification marker to identify severe and symptomatic carotid artery stenosis

Abstract

BackgroundThe main pathological change causing carotid artery stenosis is atherosclerosis, and studies suggest that tumor necrosis factor-stimulated gene-6 (TSG-6) has an anti-atherogenic effect and may be a new target for the diagnosis of carotid artery stenosis disease. We hypothesized that serum TSG-6 levels might also be associated with carotid artery stenosis. The aim of this study was to evaluate the diagnostic significance and potential predictive value of serum TSG-6 levels in patients with severe carotid artery stenosis and symptomatic stenosis. MethodsSerum TSG-6 levels were measured in 96 patients with carotid stenosis and 40 sex and age matched control healthy subjects. The expression of TSG-6 in carotid plaques (4 severe stenoses, 4 moderate stenoses, and 4 mild stenoses) and 4 superficial temporal artery vascular tissues of 12 patients with carotid stenosis who underwent endarterectomy at our hospital were detected by Western blot. Histological analysis of carotid plaque and superficial temporal artery tissues was also performed. ResultsCompared with controls, serum TSG-6 levels were higher in patients with carotid stenosis, TSG-6 expression was increased in tissues with moderate and severe stenosis, and TSG-6 expression was significantly higher in the fibrous cap component of the plaque than in the non-fibrous cap component. Serum TSG-6 levels were higher in patients with symptomatic stenosis than in patients with asymptomatic stenosis. Tissue TSG-6 staining levels and serum TSG-6 levels were positively correlated (r = 0.694, p < 0.05) and tissue TSG-6 staining levels were positively correlated with macrophage staining levels (r = 0.932, p < 0.05). Logistic regression analysis showed that serum TSG-6 was an independent factor for the presence of severe carotid stenosis and symptomatic stenosis in patients (p < 0.001). Serum TSG-6 levels were more diagnostically efficient than other indices in identifying severe and symptomatic carotid stenosis (p < 0.05), especially in identifying symptomatic stenosis (p < 0.01). We further significantly increased the diagnostic power of symptomatic stenosis using a combined model of serum TSG-6 and homocysteine (p < 0.05). ConclusionsSerum TSG-6 may serve as a new non-invasive and easily measured biomarker to better screen people with severe and symptomatic carotid stenosis in clinical practice.