Fig. 4

Tissue validation of candidate lncRNAs. A-F The expression levels of lncRNAs in gastric cancer tissue as determined by qRT-PCR. Student's t test, *, p < 0.05, **, p < 0.01, ***, p < 0.001, ****, p < 0.0001, ns, not significant. G Representative RT-PCR plots of the candidate lncRNAs. PCR products were separated by 2% agarose gel electrophoresis under 100 V for 1 h. Images were processed by Adobe Photoshop 22.1.1 software. GC-NPM, Gastric cancer patients without peritoneal metastasis; GCPM, Gastric cancer patients with peritoneal metastasis; N, tissue adjacent to tumor; T, tumor tissue. H-M ROC curve of six lncRNAs signature for the detection of GCPM. AUC, area under curve, Sen, sensitivity at the optimal cut-off value, Spe, specificity at the optimal cut-off value. N-S Kaplan-Meier survival analysis of overall survival (OS) for the lncRNA-high-expressed group and lncRNA-low-expressed group using log-rank test