Long noncoding RNA ENST00000455974 plays an oncogenic role through up-regulating JAG2 in human DNA mismatch repair-proficient colon cancer

Prognostic and predictive value of a lncRNA signature in patients with stage II colon cancer

The current staging method is inadequate to identify high-risk recurrence patients with stage II colon cancer (CC). Using a systematic and comprehensive-biomarker discovery and validation method, we aimed to construct a lncRNA-based signature to improve the prognostic prediction of stage II CC. We identified 1,377 differently expressed lncRNAs by analyzing 16 paired stage II CC tumor tissue and adjacent normal mucosal tissue from the TCGA dataset. Subsequently, using a univariable and step multivariable Cox regression model, we trained an 11-lncRNA signature in the training cohort (n = 141), which could divide patients into high-risk and low-risk groups (AUC at 3 years = 0.801, 95% CI: 0.724-0.877; AUC at 5 years = 0.801, 95% CI: 0.718-0.885). Significantly, patients in the high-risk group had poorer recurrence-free survival (RFS) compared with the low-risk group (log-rank test, P < 0.001 in the training cohort). This lncRNA-based signature was further confirmed in the validation cohort (P < 0.001). Multivariate Cox regression and stratified survival analyses showed that the prognostic value of this signature was independent of other clinicopathological risk factors (CEA, T stage, and chemotherapy). Time-dependent receiver operating characteristic (ROC) analysis demonstrated that this signature had better prognostic ability than any other clinical risk factors or single lncRNAs (all P < 0.05). A nomogram was constructed for clinical use, which integrated both the lncRNA-based signature and clinical risk factors (CEA and T stage) and performed well in the calibration plots. Altogether, our lncRNA-based signature was an independent prognostic factor and possessed a stronger predictive power compared with the currently used clinicopathological risk factors when predicting the recurrence of patients with stage II CC. Collectively, this lncRNA-based signature might facilitate individualized treatment decisions and postoperative counseling, ultimately contributing to improved survival.

Notch-associated lncRNAs profiling circuiting epigenetic modification in colorectal cancer

Background

Colorectal cancer (CRC) is one of the most prevalent digestive cancers, ranking the 2nd cause of cancer-related fatality worldwide. The worldwide burden of CRC is predicted to rise by 60% by 2030. Environmental factors drive, first, inflammation and hence, cancer incidence increase.

Main

The Notch-signaling system is an evolutionarily conserved cascade, has role in the biological normal developmental processes as well as malignancies. Long non-coding RNAs (LncRNAs) have become major contributors in the advancement of cancer by serving as signal pathways regulators. They can control gene expression through post-translational changes, interactions with micro-RNAs or down-stream effector proteins. Recent emerging evidence has emphasized the role of lncRNAs in controlling Notch-signaling activity, regulating development of several cancers including CRC.

Conclusion

Notch-associated lncRNAs might be useful prognostic biomarkers or promising potential therapeutic targets for CRC treatment.

Therefore, here-in we will focus on the role of “Notch-associated lncRNAs in CRC” highlighting “the impact of Notch-associated lncRNAs as player for cancer induction and/or progression.”

Graphical Abstract

The long non-coding RNA T cell leukemia homeobox 1 neighbor enhances signal transducer and activator of transcription 5A phosphorylation to promote colon cancer cell invasion, migration, and metastasis

Colon cancer is among the most prevalent gastrointestinal tumor types. The long noncoding RNA (lncRNA) T cell leukemia homeobox 1 neighbor (TLX1NB) is up-regulated in colorectal cancer (CRC). However, the functional role of this lncRNA in colon cancer remains unknown. In our study, we investigated the clinical significance of TLX1NB in colon cancer through bioinformatics analysis and explored its role in migration, invasion and metastasis of colon cancer cell with a series of experiments. Firstly, TLX1NB was up-regulated in colon cancer tissues and increased TLX1NB expression was significantly associated with advanced N stages. In wound healing assays and transwell assays, TLX1NB overexpression promoted HCT116 cell migration and invasion while TLX1NB knockdown inhibited SW620 cell migration and invasion. In vivo, TLX1NB knockdown suppressed pulmonary metastasis of SW620 cell and vimentin expression but increased E-cadherin expression. Then, TLX1NB overexpression enhanced signal transducer and activator of transcription 5A (STAT5A) phosphorylation and TLX1NB knockdown suppressed STAT5A phosphorylation. Moreover, the inhibition of STAT5A phosphorylation reversed TLX1NB overexpression-associated increase in HCT116 cell migratory and invasive activity. In conclusion, TLX1NB enhances STAT5A phosphorylation to promote colon cancer cell invasion, migration, and metastasis.

The Emerging Landscape of Long Non-Coding RNAs in Colorectal Cancer Metastasis

Colorectal cancer (CRC) is one of the most common gastrointestinal cancers, with extremely high rates of morbidity and mortality. The main cause of death in CRC is distant metastasis; it affects patient prognosis and survival and is one of the key challenges in the treatment of CRC. Long non-coding RNAs (lncRNAs) are a group of non-coding RNA molecules with more than 200 nucleotides. Abnormal lncRNA expression is closely related to the occurrence and progression of several diseases, including cancer. Recent studies have shown that numerous lncRNAs play pivotal roles in the CRC metastasis, and reversing the expression of these lncRNAs through artificial means can reduce the malignant phenotype of metastatic CRC to some extent. This review summarizes the major mechanisms of lncRNAs in CRC metastasis and proposes lncRNAs as potential therapeutic targets for CRC and molecular markers for early diagnosis.

LncRNA MALAT1/microRNA let-7f/KLF5 axis regulates podocyte injury in diabetic nephropathy

OBJECTIVE

The abnormal expression of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) has been demonstrated to exert pivotal effects in human diseases. We focused on the functions of metastasis associated lung adenocarcinoma transcript 1 (MALAT1) and microRNA let-7f on diabetic nephropathy (DN).

METHODS

The diabetes (db/db) mice were treated with silenced MALAT1, then the baseline indicators, pathology changes, marker proteins of podocyte injury (nephrin, podocin, desmin and Cleaved caspase-3), oxidative stress indicators and inflammatory factors in renal tissues were determined. Murine podocyte MPC5 cells were stimulated by high glucose (HG) and transfected with sh-MALAT1 or let-7f mimic, then the cell migration, adhesion ability and apoptosis were evaluated. Moreover, the binding relationship between MALAT1 and let-7f, and the targeting relationship between let-7f and krüppel-like factor 5 (KLF5) were confirmed.

RESULTS

Silenced MALAT1 could improve baseline indicators of DN mice, and also improved pathology, increased nephrin and podocin expression, decreased desmin and Cleaved caspase-3 expression, and restrained oxidative stress and inflammatory reaction in their renal tissues. Additionally, elevated let-7f and reduced MALAT1 could restrict migration and apoptosis of HG-induced MPC5 cells, and promoted the cell adhesion ability.

CONCLUSION

Results in our research indicated that the reduced MALAT1 could relieve the podocyte injury in DN by upregulating let-7f and inhibiting KLF5, which may be helpful for DN therapy.

Long noncoding RNAs: functions and mechanisms in colon cancer

Evidence indicates that long non-coding RNAs (lncRNAs) play a crucial role in the carcinogenesis and progression of a wide variety of human malignancies including colon cancer. In this review, we describe the functions and mechanisms of lncRNAs involved in colon oncogenesis, such as HOTAIR, PVT1, H19, MALAT1, SNHG1, SNHG7, SNHG15, TUG1, XIST, ROR and ZEB1-AS1. We summarize the roles of lncRNAs in regulating cell proliferation, cell apoptotic death, the cell cycle, cell migrative and invasive ability, epithelial-mesenchymal transition (EMT), cancer stem cells and drug resistance in colon cancer. In addition, we briefly highlight the functions of circRNAs in colon tumorigenesis and progression, including circPPP1R12A, circPIP5K1A, circCTIC1, circ_0001313, circRNA_104916 and circRNA-ACAP2. This review provides the rationale for anticancer therapy via modulation of lncRNAs and circular RNAs (circRNAs) in colon carcinoma.

LncRNA NEAT1/microRNA-129-5p/SOCS2 axis regulates liver fibrosis in alcoholic steatohepatitis

Background

Long non-coding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) has been reported to play an essential role in non-alcoholic fatty liver disease. However, the role of NEAT1 in regulation of alcoholic steatohepatitis (ASH) remains largely unknown. This study aims to explore the role of NEAT1 in ASH by mediating microRNA-129-5p (miR-129-5p) targeting suppressor of cytokine signaling 2 (SOCS2).

Methods

NEAT1, miR-129-5p and SOCS2 expression in serum of ASH patients were assessed. In the in vitro cellular experiment, we transfected siRNAs, oligonucleotides or plasmids into ethanol-induced AML-12 mouse hepatocytes to alter NEAT1 and miR-129-5p expression, and inflammatory factors and lipid content were determined. In the in vivo animal experiment, we injected lentiviruses carrying siRNAs, oligonucleotides or plasmids onto ASH mice (ASH induced by feeding mice a Lieber-DeCarli ethanol diet) to alter NEAT1 and miR-129-5p expression through the tail vein. Serum liver function, blood lipids and inflammatory factors were detected; liver histopathology, liver cell apoptosis, and fibrosis were observed. The relationship between NEAT1 and miR-129-5p, or between miR-129-5p and SOCS2 was verified.

Results

MiR-129-5p was reduced while NEAT1 and SOCS2 were elevated in ASH. Inhibited NEAT1 or elevated miR-129-5p suppressed the elevated lipid metabolism and restrained inflammation reaction in ethanol-stimulated AML-12 cells. The promoted miR-129-5p and inhibited NEAT1 could improve the liver function and repress blood lipid, inflammation reaction, hepatocyte apoptosis and liver fibrosis in ethanol-induced ASH mice. Furthermore, NEAT1 could negatively regulate miR-129-5p to target SOCS2.

Conclusion

We have found that the inhibited NEAT1 could suppress liver fibrosis in ASH mice by promoting miR-129-5p and restraining SOCS2, thereby decelerating the development of ASH.

Overexpression of long non-coding RNA00355 enhances proliferation, chemotaxis, and metastasis in colon cancer via promoting GTF2B-mediated ITGA2

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LncRNA LINC00355 promotes colon cancer malignancy.

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LncRNA LINC00355 positively regulates ITGA2 via recruiting GTF2B.

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LncRNA LINC00355 positively regulates GTF2B-mediated ITGA2 to promote colon cancer.

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This study proposes a novel targeted strategy for cancer treatment.

Long non-coding RNAs (LncRNAs) can regulate physiological and pathological functions, exhibiting a wide range of roles in cell biology. Moreover, many lncRNAs are dysregulated in various cancers, including colon cancer. In this study, we investigated the role of the lncRNA LINC00355 in colon cancer, after first establishing its interaction with GTF2B, and ITGA2 on the LncMap database. The predicted relationships between the lncRNA LINC00355, GTF2B, and ITGA2 were identified using luciferase reporter assay, RIP, and ChIP experiments. Western blot analysis and RT-qPCR were applied to determine expression pattern of lncRNA LINC00355 and ITGA2 in colon cancer cells. Additionally, EdU, TUNEL, Cell-adhesion and Transwell assay was used for the detection of the effects of this axis on proliferation, apoptosis, adhesion, chemotaxis and metastasis. LncRNA LINC00355 targeted IGFBP2 through the recruitment of GTF2B. LncRNA LINC00355 was highly expressed in colon cancer cells, and overexpression of lncRNA LINC00355 increased the expression of IGFBP2 and GTF2B, and thereby promoted the proliferation, chemotaxis, invasion, and migration in colon cancer. In summary, downregulation of lncRNA LINC00355 in colon cancer inhibited tumor growth in colon cancer through effects on the GTF2B/IGFBP2 axis.

Clinical diagnostic value of long non-coding RNAs in Colorectal Cancer: A systematic review and meta-analysis

Background: Histopathological diagnosis remains the gold standard for the diagnosis of cancer, including colorectal cancer, but it is infeasible when tumor tissue is not available. With the recognition of long non-coding RNAs (lncRNAs), the expression of lncRNAs in serum or tissue samples has been reported as a diagnosis method for some cancers, however, the diagnostic value of lncRNAs for colorectal cancer remains unclear.

Methods: A systematic review and meta-analysis were conducted. Eligible studies were identified through a comprehensive literature search in PubMed, PubMed Central, Web of Science, Embase, and Cochrane Library (up to May 05, 2020) according to the selection criteria. Meta-DiSc, Review Manager and STATA were used to analyze the association between lncRNAs expression and the diagnosis of colorectal cancer.

Results: Fifteen studies that analyzed the expression of 15 lncRNAs in 1434 CRC patients were included. The summary area under the curve (AUC) of lncRNA for the diagnosis efficacy between patients with and without CRC was estimated to be 0.8629, corresponding to a weighted sensitivity of 0.75 (95% CI: 0.72 - 0.77), specificity of 0.80 (95%CI: 0.78 - 0.82). Subgroup analysis illustrated that the AUC of blood-based detection of lncRNA showed 0.8820, pooled DOR: 18.57, while tissue-based analysis showed 0.8203, pooled DOR: 10.47. Blood-based tests were then divided into two categories, plasma-based and serum-based lncRNA testing. Results revealed that the AUC of serum-based detection was 0.9077, pooled DOR: 26.64, and plasma-based detection was 0.5000, pooled DOR: 11.80.

Conclusions: This meta-analysis indicates that the aberrantly expressed lncRNAs might serve as potential diagnostic biomarkers for CRC patients and blood-based lncRNA analysis is of higher diagnostic accuracy than tissue-based testing. Moreover, serum-based lncRNA testing achieved higher diagnostic efficacy than plasma-based analysis.

Roles of DANCR/microRNA-518a-3p/MDMA ceRNA network in the growth and malignant behaviors of colon cancer cells

Background

The competing endogenous RNA (ceRNA) networks of long non-coding RNAs (lncRNAs) and microRNAs (miRs) have aroused wide concerns. The study aims to investigate the roles of lncRNA DANCR-associated ceRNA network in the growth and behaviors of colon cancer (CC) cells.

Methods

Differentially expressed lncRNAs between CC and paracancerous tissues were analyzed using microarrays and RT-qPCR. Follow-up studies were conducted to evaluate the correlation between DANCR expression and prognosis of CC patients. Loss-of-functions of DANCR were performed to identify its role in the malignant behaviors of CC cells. Sub-cellular localization of DANCR and the potential targets of DANCR were predicted and validated. Cells with inhibited DANCR were implanted into nude mice to evaluate the tumor formation and metastasis in vivo.

Results

DANCR was highly-expressed in CC tissues and cell lines, and higher levels of DANCR were linked with worse prognosis and less survival time of CC patients. Silencing of DANCR inhibited proliferation, viability, metastasis and resistance to death of CC cells. DANCR was found to be sub-localized in cytoplasmic matrix and to mediate murine double minute 2 (MDM2) expression through sponging miR-518a-3p in CC cells, during which the Smad2/3 signaling was activated. Likewise, silencing of DANCR in CC cells inhibited tumor formation and metastasis in vivo.

Conclusion

This study provided evidence that silencing of DANCR might inhibit the growth and metastasis of CC cells through the DANCR/miR-518a-3p/MDM2 ceRNA network and the defect of Smad2/3 while activation of the p53 signaling pathways. This study may offer novel insights in CC treatment.

Diagnostic and prognostic potential of tissue and circulating long non-coding RNAs in colorectal tumors

Long non-coding RNAs (lncRNAs) are members of the non-protein coding RNA family longer than 200 nucleotides. They participate in the regulation of gene and protein expression influencing apoptosis, cell proliferation and immune responses, thereby playing a critical role in the development and progression of various cancers, including colorectal cancer (CRC). As CRC is one of the most frequently diagnosed malignancies worldwide with high mortality, its screening and early detection are crucial, so the identification of disease-specific biomarkers is necessary. LncRNAs are promising candidates as they are involved in carcinogenesis, and certain lncRNAs (e.g., CCAT1, CRNDE, CRCAL1-4) show altered expression in adenomas, making them potential early diagnostic markers. In addition to being useful as tissue-specific markers, analysis of circulating lncRNAs (e.g., CCAT1, CCAT2, BLACAT1, CRNDE, NEAT1, UCA1) in peripheral blood offers the possibility to establish minimally invasive, liquid biopsy-based diagnostic tests. This review article aims to describe the origin, structure, and functions of lncRNAs and to discuss their contribution to CRC development. Moreover, our purpose is to summarise lncRNAs showing altered expression levels during tumor formation in both colon tissue and plasma/serum samples and to demonstrate their clinical implications as diagnostic or prognostic biomarkers for CRC.