Human sample collection
The peripheral blood and tissue samples of 30 cases pathologically-diagnosed with HCC in the General Surgery Department at Tianjin Medical University General Hospital were collected prior to surgery from October 2015 to July 2017. Tumor tissues and paired non-tumor control tissues were at distances > 5 cm. All specimens were divided into two aliquots: one aliquot was frozen at −80 °C for protein extraction; and the other specimen was fixed with 4% formalin for immunohistochemical (IHC) detection. Peripheral venous blood  (2–3ml) were obtained from 20 volunteers who served as healthy controls. The study was planned according to the ethical guidelines following the Declaration of Helsinki. This project was approved by the Ethics Committee of Tianjin Medical University General Hospital. All subjects gave informed consent prior to enrollment in the investigation.