Hsa_circ_0004071 in plasma exosomes as a new diagnostic marker for colorectal cancer

Objective To screen out the differentially expressed circRNA in plasma exosomes of patients with colorectal cancer (CRC) and identify its feasibility as a new diagnostic biomarker for CRC. Methods Plasma samples were collected from 48 CRC patients who were admitted to the Affiliated Hospital of Xuzhou Medical University from October 2019 to July 2020 and set as an observation group. Meanwhile, plasma samples were also collected from 48 non-cancer patients who were admitted during the same period as a control group. Differential circRNAs were carried out through preliminary experiments. Then plasma exosomes and total RNA were extracted, and reverse transcription and RT-PCR quantitative analysis were performed. The final target circRNAs were selected for in-depth verification. Results Totally, 15 differentially expressed circRNAs were screened out through bioinformatics analysis. RT-PCR quantitative analysis indicated that the target gene Hsa_circ_0004071 was significantly differentially expressed in plasma exosomes of CRC patients and those in the non-cancer control groups. The diagnostic analysis results showed the pooled sensitivity was 77% and the specificity was 71%, with the area under the curve of 0.7552. These findings indicated that Hsa_circ_0004071 had high diagnostic efficiency for CRC patients, and the abnormal expression of Hsa_circ_0004071 was positively correlated with TNM staging and distant metastasis in CRC. Conclusions Hsa_circ_0004071 is highly expressed in plasma exosomes of CRC patients, which is related to TNM staging and distant metastasis. It may become a new diagnostic marker for CRC.