Expression and diagnostic value of CCT3 and IQGAP3 in hepatocellular carcinoma.

BACKGROUND: To evaluate plasma chaperonin containing TCP1 complex subunit 3 (CCT3) and IQ-motif-containing GTPase-activating protein-3 (IQGAP3) as biomarker for hepatocellular carcinoma (HCC) screening and diagnosis. METHODS: Blood samples were collected from 126 HCC patients with HCC, 88 patients with cirrhosis and 50 healthy volunteers to detect plasma α-fetoprotein (AFP), CCT3 and IQGAP3 levels. Plasma AFP, CCT3 and IQGAP3 protein levels were measured by enzyme linked immunosorbent assay (ELISA). RESULTS: In the plasma of HCC patients, both CCT3 and IQGAP3 were significantly higher than in patients with cirrhosis and in healthy controls (P < 0.01). CCT3 and IQGAP3 protein level correlated well with HCC etiology, tumor size, TNM stage, and child-pugh classification. CCT3 protein had higher sensitivity in the diagnosis of HCC when compared with AFP (87.3 vs 69.8 %). In addition, CCT3 and IQGAP3 protein were able to complement AFP in detecting AFP-negative HCC patients with sensitivity and specificity of 92.1 and 70.5 % and 81.6 and 71.6 %, respectively. In the small HCC group, CCT3 and IQGAP3 protein had sensitivity of 76.6 and 74.5 %, respectively. The combination of AFP + CCT3 + IQGAP3 (0.954) had significantly superior discriminative ability than AFP alone (0.815; P < 0.01). CONCLUSIONS: CCT3 and IQGAP3 are novel complementary biomarkers for HCC screening and diagnosis, especially for AFP-negative and small HCC patients.