Circular RNA hsa_circ_0078602 may have potential as a prognostic biomarker for patients with hepatocellular carcinoma

Circular RNA (circRNA), a type of endogenous non-coding RNA, is a closed continuous loop of RNA with no poly(A) tail. Previously, studies have identified that circRNAs are closely associated with several cancer types. However, their function in hepatocellular carcinoma (HCC) has rarely been studied. Therefore, the aim of the current study was to screen differential circRNA expression between HCC tissues and adjacent non-cancerous tissues, and test the potential clinical value of individual circRNAs. CircRNA microarray was used to investigate global circRNA expression profiles. Attention was then focused on the top four circRNAs whose expression levels were reduced in HCC tissues as compared with non-cancerous tissues. Additionally, RNA expression was validated in 30 matched tissue samples using reverse transcription-quantitative polymerase chain reaction. The results revealed that the expression levels of hsa_circ_0078602 and hsa_circ_0018764 were consistent with microarray analysis (P<0.05). Between these two circRNAs, hsa_circ_0078602 demonstrated an association with a favorable diagnostic efficiency, with an area under the receiver operating characteristic curve of 0.787 (P<0.001). To further verify the expression level of hsa_circ_0078602, the patient sample size was increased to 79. The results supported the conclusion that circ_0078602 was downregulated in HCC tissue compared with non-cancerous tissue (P=0.015) and exhibited diagnostic potential. Notably, it was identified that a lower hsa_circ_0078602 expression level was associated with a worse prognosis among patients with HCC. In addition, it was revealed that 9.0×10^-5 was the most efficient cut-off value of hsa_circ_0078602 expression to assess the outcomes of patients with HCC. The present study revealed that hsa_circ_0078602 may be a novel diagnostic biomarker of HCC and therefore have potential prognostic value.