Clinical significance of cylindromatosis expression in primary hepatocellular carcinoma

Background and study aim: There is currently a lack of sensitive biomarkers for the diagnosis of hepatocellular carcinoma (HCC). Low expression of cylindromatosis (CYLD), a tumor suppressor gene that encodes a deubi-quitinase, is associated with the development of HCC. The present study, therefore, aimed to determine the clinical utility of measuring CYLD expression in the early diagnosis of HCC.Patients and methods: The present study comprised 257 patients from the Affiliated Hospital of Qingdao Uni-versity including 90 patients with HCC, 41 patients with liver cirrhosis (LC), 46 patients with hepatitis B (HB), and 80 healthy controls. qPCR was used to measure the amounts of CYLD mRNA in stored blood samples. The sensitivity and specificity of CYLD mRNA in diagnosing HCC was analyzed using receiver operator characteristic (ROC) curves. We also obtained HCC data from the Oncomine database to further verify our results.Results: The relative levels of CYLD mRNA in peripheral blood from patients with HCC (median, 0.060; inter -quartile range [IQR], 0.019-0.260) was significantly lower than in blood from patients with LC (median, 3.732; IQR, 0.648-14.573), HB (median, 0.419; IQR, 0.255-1.809) and healthy controls (median, 1.262; IQR, 0.279-3.537; P < 0.05). CYLD mRNA levels in peripheral blood were significantly higher in patients with LC compared to healthy controls and patients with HB. Oncomine data demonstrated that CYLD mRNA expression levels in HCC tissues were significantly lower than in normal liver tissues. ROC analysis demonstrated that the combined use of peripheral blood levels of CYLD and AFP had the greatest diagnostic accuracy for HCC (area under the curve (AUC), 0.897; 95 % confidence interval [CI], 0.853-0.942). CYLD had utility as a supplementary marker to AFP for diagnosing HCC.Conclusion: Circulating levels of CYLD mRNA are significantly decreased in patients with HCC, indicating CYLD may have utility as a biomarker of HCC. Combined measurement of CYLD mRNA and AFP protein had the greatest diagnostic accuracy.