Proteome Expression Profile for Red Blood Cells Enables Diagnostics for Hepatocellular Carcinoma

BackgroudEarly diagnosis of hepatocellular carcinoma (HCC) has not been clinically resolved, which has been causing more death in patients with HCC. HCC is also a systemic disease related to disorders of blood homeostasis, and the association of red blood cells (RBCs) and HCC tumorigenesis is still elusive. This study explored the protein characteristics of RBCs at the progressive pathological stages comparing with healthy individuals, including liver cirrhosis (LC) and established HCC, to fully understand the tumorigenesis of HCC from a different view and identify potentially novel diagnostic biomarkers for HCC in RBCs.MethodsData independent acquisition (DIA) proteomic analyses were performed with 72 clinical RBCs samples from a cohort of subjects including HCC, LC and healthy controls. Bioinformatics analysis was conducted for significantly differentially expressed proteins (DEPs) through the whole process of tumorigenesis to characterize the clinical relevanve of RBCs and tumorigenesis in HCC. The highly potential tumorigenesis-associated molecular biomarkers were evaluated with clinical samples by parallel reaction monitoring (PRM) technology.ResultsWe observed that red blood cells number dynamically changes during the tumorigenesis of HCC, and LC is a developmental stage more closely approaching HCC based on the protein expresson profiles in RBCs. The expression of hemoglobin (HbA, HbF) in erythroid cells also dynamically alters during the whole process of HCC tumorigenesis, suggesting immature erythroid cells exist in peripheral blood of HCC patients and erythropoiesis in the patients starts to be influenced with the occurance of LC. We observed that the autophagy pathway is disturbed in RBCs with the onset of LC and maintained during the tumorigenesis of HCC. Oxytocin pathway and GnRH pathway are disturbed and first identified during the development of LC into HCC. SMIM1, ANXA7, HBA1 and HBE1 that are significantly altered during tumorigenesis were verified as promising biomarkers for HCC early diagnosis.ConclusionsThis study underlied the clinical relevance of the proteins in RBCs and the tumorigenesis of HCC, and provided the potential biomarkers for early diagnosis in HCC from a new perspective. Our results provided a novel strategy with RBCs for HCC early diagnosis, which will improve the translational research and application in diagnosis of HCC.