The prognostic role of tissue and serum transthyretin expression in patients with surgically resected non-small cell lung cancer

Abstract Background Transthyretin (TTR) is a traditional biomarker for nutritional and inflammatory. The present study was conducted to explore the clinical value of TTR in serum and tumor tissue in patients with surgically resected non-small cell lung cancer (NSCLC). Methods TTR expression levels were determined in paraffin-embedded NSCLC tissue specimens using immunohistochemistry. Serum TTR expression levels were measured from patients with lung cancer and healthy controls using enzyme-linked immunosorbent assay (ELISA). Results The expression levels of TTR were significantly higher in lung cancer tissues than in paracancerous tissues, and TTR expression was significantly associated with TNM stage (P = 0.002) and lymph node metastasis (P = 0.032). Multivariate analysis revealed that increased expression of TTR was an independent risk factor for overall survival (OS) (P = 0.012) and disease-free survival (DFS) (P = 0.011) in NSCLC patients. The expression levels of TTR in serum from lung cancer patients were lower than those of healthy controls (P = 0.002). A high expression of TTR in tumor tissue was associated with a higher serum level (r = 0.799, P = 0.001). Conclusions TTR expression is upregulated in lung cancer patients, and its expression was correlated with poor prognosis in NSCLC patients.