Quantification of plasma hTERT DNA in hepatocellular carcinoma patients by quantitative fluorescent polymerase chain reaction.

PURPOSE To investigate the levels of human telomerase reverse transcriptase (hTERT) DNA in the plasma of patients with hepatocellular carcinoma (HCC), and to evaluate the diagnostic value and correlation of hTERT DNA with clinical parameters in HCC. METHODS A real-time quantitative fluorescent polymerase chain reaction (FQ-PCR) system was designed and evaluated. Plasma samples were collected from 60 HCC patients, 21 patients with hepatitis B virus (HBV) and 29 healthy controls. Plasma DNA was extracted and quantified by FQ-PCR. The diagnostic value of plasma hTERT DNA levels and their relationships with clinical characteristics were analyzed statistically. RESULTS Plasma levels of hTERT DNA in HCC patients were significantly higher than in HBV patients (4.18×104±4.94×104 copies/μl vs 1.21×104±6.63×103 copies/μl, P=0.003) and healthy controls (4.18×104±4.94×104 copies/μl vs 1.44×104±6.61×103 copies/μl, P < 0.001). Receiver operating characteristic curve analysis indicated a sensitivity of 64% and a specificity of 90% for the ability of hTERT DNA levels to detect malignancy at a cutoff value of 1.87×104 copies/μl. Association analysis revealed that plasma hTERT DNA levels were closely related to tumor size, portal vein cancer embolus and TNM stage (P=0.013, P=0.010, and P=0.029, respectively), but were not associated with lymph node metastasis, hepatitis B surface antigen, or α-fetoprotein (AFP) (all P > 0.05). The levels of plasma hTERT DNA in HCC patients with AFP ≤20 ng/ml were significantly higher than in HBV patients (4.59×104±4.98×104 copies/μl vs 1.44×104±6.63×103 copies/μl, P=0.016) and in healthy controls (4.59×104±4.98×104 copies/μl vs 1.21×104±6.63×103 copies/μl, P=0.001). CONCLUSIONS Quantitation of plasma hTERT DNA by FQ-PCR may provide a novel complementary tool with potential clinical applications for the screening and detection of HCC. Plasma hTERT DNA has the potential to be a broad tumor marker for common cancers.