Colorectal cancer (CRC) is the third most common cancer and the second leading cause of cancer mortality worldwide. Emerging evidence indicates that tumour cells release substantial amounts of RNA into the bloodstream, in which RNA strongly resists RNases and is present at sufficient levels for quantitative analyses. Our study aimed to discover blood‐based markers for the early detection of CRC and to ascertain their efficiency in discriminating healthy controls, patients with polyps and adenomas and cancer patients. We first analysed and screened ZFAS1, SNHG11, LINC00909 and LINC00654 in a bioinformatics database and then collected clinical plasma samples for preliminary small‐scale analysis and further large‐scale verification. We then explored the mechanism of dominant lncRNA SNHG11 expression in CRC by in vitro and in vivo assays. The combination of ZFAS1, SNHG11, LINC00909 and LINC00654 showed high diagnostic performance for CRC (AUC: 0.937), especially early‐stage disease (AUC: 0.935). Plasma levels of the four candidate lncRNAs were significantly reduced in postoperative samples compared to preoperative samples. A panel including these four lncRNAs performed well in distinguishing patient groups with different stages of colon disease, and SNHG11 exhibited the greatest diagnostic ability to identify precancerous lesions and early‐stage tumour formation. Mechanistically, high SNHG11 expression promotes proliferation and metastasis by targeting the Hippo pathway. Taken together, the data indicate that SNHG11 may be a novel therapeutic target for the treatment of CRC and a potential biomarker for the early detection of CRC.

Background : Recent studies have shown that circulating long noncoding RNAs (lncRNAs) could be stably detectable in the blood of cancer patients and play important roles in the diagnosis of many different cancers. However, the value of lncRNAs in the diagnosis of pancreatic cancer (PC) has not been fully explored. Methods : Eleven PC-related lncRNAs were selected by analyzing bioinformatics databases. The expression levels of the lncRNAs were further analyzed in a small set of plasma samples from a training group including 30 noncancer samples (15 healthy and 15 chronic pancreatitis (CP) subjects) and 15 PC samples. Then, the candidate lncRNAs were validated with data from 46 healthy controls, 97 CP patients and 114 PC patients. Receiver operating characteristic (ROC) curves were employed to evaluate the diagnostic performance of the identified lncRNAs. Results : After selection and validation, three characteristic plasma candidate lncRNAs, ABHD11-AS1, LINC00176 and SNHG11, were identified, and their levels were significantly higher in PC patients than in normal controls. We found that among the three candidate lncRNAs, ABHD11-AS1 showed the best diagnostic performance for the detection of PC. Furthermore, ABHD11-AS1 had a higher area under the ROC curve (AUC) than CEA, CA199 and CA125 for early PC diagnosis, while the combination of ABHD11-AS1 and CA199 was more effective than ABHD11-AS1 alone. Conclusions : Plasma ABHD11-AS1 could serve as a potential biomarker for detecting PC, and the combination of ABHD11-AS1 and CA199 was more efficient for the diagnosis of PC than ABHD11-AS1 alone, particularly for early tumor screening.