The Clinical Diagnostic Value of the Super-enhancer-associated Long Noncoding RNA RP11-803D5.4 and AC005592.2 in Colorectal Cancer

Background: Super-enhancer-associated long noncoding RNAs (SE-lncRNAs) play crucial roles in CRC pathogenesis. Objective: RP11-803D5.4 and AC005592.2 were identified as SE-lncRNAs of interest via microarray analysis, and our study aimed to evaluate their clinical value in CRC diagnosis and prognosis assessment. Methods: Fluorescence quantitative real-time PCR (qRT-PCR) was used to measure the expression of RP11-803D5.4 and AC005592.2 in the tissues and serum of CRC patients. Receiver operating characteristic (ROC) curves were generated to determine the predictive value of the two SE-lncRNAs. Functional assays were applied to assess the ability of RP11-803D5.4 to promote the proliferation, migration, and invasion of CRC cells. Results: The two SE-lncRNAs were significantly upregulated in CRC tissue and serum samples vs. corresponding controls. ROC curve analysis indicated that RP11-803D5.4 (AUC=0.842) and AC005592.2 (AUC=0.811) had a high diagnostic performance for CRC. The combination of RP11-803D5.4, AC005592.2, and CEA had an AUC of 0.946 and distinguished CRC patients and healthy controls better than SE-lncRNA alone. The serum levels of RP11-803D5.4 and AC005592.2 were strongly correlated with their tissue expression levels. The expression levels of the two SE-lncRNAs were significantly lower in postoperative samples than in preoperative samples. Furthermore, similar to the findings of previous studies on AC005592.2, high RP11-803D5.4 expression promoted the proliferation, invasion, and migration of CRC cells. Conclusion: The findings suggested that RP11-803D5.4 and AC005592.2 are upregulated in CRCact and are crucial promoters of CRC progression. They also suggested that they might serve as noninvasive biomarkers for diagnosing CRC.