ObjectiveTo explore the predictive value of microRNA-215 (miR-215) and microRNA-7-5p (miR-7-5p) expression levels in gastric cancer tissues for recurrence after endoscopic submucosal dissection (ESD) based on restricted cubic spline (RCS). MethodsA total of 200 patients with early gastric cancer who underwent ESD in Yibin Second People’s Hospital from August 2020 to August 2022 were prospectively selected. The patients were followed up for 2 years, and the postoperative recurrence was counted. RCS was used to analyze the predictive value of miR-215 and miR-7-5p expression levels in gastric cancer tissues for recurrence after ESD and the dose-response relationship with recurrence after ESD. Helicobacter pylori (HP) infection, tumor maximum diameter, depth of invasion, carbohydrate antigen 724 (CA724), and neutrophils to lymphocytes ratio (NLR) levels were included to construct a basic nomogram prediction model, and miR-215, miR-7-5p, HP infection, tumor maximum diameter, depth of invasion, CA724, and NLR were included to construct a new nomogram prediction model. The value of the two models in predicting recurrence after ESD was compared. The clinical data of 84 patients with early gastric cancer who underwent ESD in Deyang People’s Hospital from September 2022 to September 2023 were retrospectively collected for external validation. ResultsDuring the follow-up period, 5 of 200 patients with early gastric cancer were lost to follow-up, and 195 patients were included and analyzed. The recurrence rate after ESD was 11.28% (22/195). The expression level of miR-215 in gastric cancer tissues of recurrence group and non-recurrence group [recurrence group: (0.67±0.15) vs. (0.97±0.24); non-recurrence group: (0.84±0.19) vs. (0.98±0.26)], miR-7-5p [recurrence group: (0.45±0.12) vs. (1.59±0.36); non-recurrence group:(0.68±0.20) vs. (1.61±0.37)] were lower than those in adjacent tissues (P<0.05). The expression level of non-recurrence group: (0.68±0.20) vs. (1.61±0.37)] was lower than that of adjacent tissues (P<0.05). The expression levels of miR-215 (OR=0.850, P=0.008) and miR-7-5p (OR=0.798, P=0.005) in gastric cancer tissues were the influencing factors of recurrence after ESD. There was a linear dose-response relationship between the expression levels of miR-215 and miR-7-5p in gastric cancer tissues and the recurrence after ESD (Poverall=0.009, Poverall<0.001; Pnonlinear=0.923, Pnonlinear=0.786). The area under curve (AUC) of the new nomogram prediction model including miR-215, miR-7-5p, HP infection, tumor maximum diameter, depth of invasion, CA724 and NLR for predicting recurrence after ESD was 0.964 [95%CI (0.900, 0.981)], which was greater than 0.857 [95%CI (0.796, 0.892)] of the basic nomogram prediction model, Z=2.158, P=0.032. The new nomogram prediction model has a high degree of calibration in predicting recurrence after ESD, and the clinical effect was good. External validation showed that the AUC of the new nomogram prediction model for predicting recurrence after ESD was 0.945 [95%CI (0.886, 0.978)], and the calibration degree for predicting recurrence after ESD was high and the clinical utility was good. ConclusionsThe expression levels of miR-215 and miR-7-5p in gastric cancer tissues of patients with early gastric cancer are lower than those in adjacent tissues, and there is a linear dose-response relationship with recurrence after ESD. The nomogram prediction model based on the expression levels of miR-215 and miR-7-5p in gastric cancer tissues can provide a reliable clinical basis for clinical prediction of postoperative recurrence.
