Expression of plasma exosomal circLPAR1 in patients with gastric cancer and its clinical application value

Objective: To determine plasma exosomal circular RNA LPAR1 (circLPAR1) expression in gastric cancer (GC) and analyze its clinical value in GC diagnosis and prognosis evaluation. Methods: The research subjects were 64 GC patients, 30 chronic gastritis (CG) patients (disease control group) and 30 healthy controls (HCs; healthy control group). RT-PCR quantified circLPAR1 expression in GC tissues and adjacent counterparts of GC patients as well as plasma exosomal circLPAR1 in each group. The correlation of differentially expressed circLPAR1 with clinicopathological indexes was analyzed, and receiver operating characteristics (ROC) and Kaplan-Meier curves were drawn to evaluate the value of plasma exosomal circLPAR1 in GC diagnosis and prognosis assessment. Results: GC patients exhibited lower plasma exosomal circLPAR1 levels than CG patients and HCs (P<0.05). Lower circLPAR1 expression was determined in GC tissues than in adjacent counterparts (P<0.05), and a positive connection between GC tissue circLPAR1 and plasma exosomal circLPAR1 was identified in GC patients (P<0.05). Evidently elevated plasma exosomal circLPAR1 was observed in post-surgical GC patients (P<0.05). ROC curves showed that the areas under the curve (AUCs) of plasma exosomal circLPAR1, serum carcinoembryonic antigen (CEA), and serum carbohydrate antigen 19-9 (CA19-9) for the diagnosis of GC were 0.836, 0.767 and 0.746, respectively, and the AUC of their combined diagnosis was 0.914. Low plasma exosomal circLPAR1 was strongly linked to tumor size, differentiation degree, tumor-node-metastasis (TNM) staging, vascular invasion, lymphatic metastasis, and HER2 expression of GC patients (P<0.05). GC patients with high plasma exosomal circLPAR1 expression had significantly longer prognostic survival time than those with low expression (P<0.05). According to univariate and multivariate Cox regression analyses, tissue differentiation degree (HR=1.415), TNM stage (HR=1.637), HER2 expression (HR=1.831), and low plasma exosomal circLPAR1 expression (HR=2.042) were risk factors for adverse prognosis in GC patients. Conclusions: circLPAR1 expression is related to GC progression, and the detection of plasma exosomal circLPAR1 has promising clinical application value in assisting the diagnosis and prognosis evaluation of GC.