Role of signal peptide-Cub-Egf domain-containing protein-1 in serum as a predictive biomarker of outcome after severe traumatic brain injury.

Background: Signal peptide-Cub-Epidermal growth factor domain-containing protein 1 (SCUBE1), a marker for coagulation, is secreted under hypoxia and inflammatory conditions from platelet α granules. This study was designed to determine the associations of serum SCUBE1 concentrations with trauma severity and prognosis after severe traumatic brain injury.

Methods: Serum SCUBE1 concentrations of 113 patients and 113 controls were measured. An unfavorable outcome was defined as Glasgow Outcome Scale score of 1-3.

Results: Serum SCUBE1 concentrations were significantly higher in patients than in controls (15.5 ± 6.0 vs. 1.1 ± 0.3 ng/ml, P < 0.001) and were associated with Glasgow coma scale scores (r = -0.439, P < 0.001) and blood platelet count (r = 0.420, P < 0.001). SCUBE1 was identified as an independent prognostic marker of 6-month unfavorable outcome (odds ratio, 1.357; 95% confidence interval, 1.159-1.589; P < 0.001), and had high predictive value according to receiver operating characteristic curve (area under curve, 0.830; 95% confidence interval, 0.748-0.890; P < 0.001).

Conclusions: Increased serum SCUBE1 concentrations are associated highly with trauma severity, platelet activation and poor outcome, suggesting that SCUBE1 might be a novel prognostic biomarker after traumatic brain injury.