Long non-coding RNA SNHG6 increases JAK2 expression by targeting the miR-181 family to promote colorectal cancer cell proliferation

Exploring the Key Signaling Pathways and ncRNAs in Colorectal Cancer

Colorectal cancer (CRC) is the third most prevalent cancer to be diagnosed, and it has a substantial mortality rate. Despite numerous studies being conducted on CRC, it remains a significant health concern. The disease-free survival rates notably decrease as CRC progresses, emphasizing the urgency for effective diagnostic and therapeutic approaches. CRC development is caused by environmental factors, which mostly lead to the disruption of signaling pathways. Among these pathways, the Wingless/Integrated (Wnt) signaling pathway, Phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) signaling pathway, Mitogen-Activated Protein Kinase (MAPK) signaling pathway, Transforming Growth Factor-β (TGF-β) signaling pathway, and p53 signaling pathway are considered to be important. These signaling pathways are also regulated by non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs). They have emerged as crucial regulators of gene expression in CRC by changing their expression levels. The altered expression patterns of these ncRNAs have been implicated in CRC progression and development, suggesting their potential as diagnostic and therapeutic targets. This review provides an overview of the five key signaling pathways and regulation of ncRNAs involved in CRC pathogenesis that are studied to identify promising avenues for diagnosis and treatment strategies.

MicroRNA-18a prevents senescence of mesenchymal stem cells by targeting CTDSPL

Stem cell therapy requires massive-scale homogeneous stem cells under strict qualification control. However, Prolonged ex vivo expansion impairs the biological functions and results in senescence of mesenchymal stem cells (MSCs). We investigated the function of CTDSPL in the premature senescence process of MSCs and clarified that miR-18a-5p played a prominent role in preventing senescence of long-term cultured MSCs and promoting the self-renewal ability of MSCs. Over-expression of CTDSPL resulted in an enlarged morphology, up-regulation of p16 and accumulation of SA-β-gal of MSCs. The reduced phosphorylated RB suggested cell cycle arrest of MSCs. All these results implied that CTDSPL induced premature senescence of MSCs. We further demonstrated that miR-18a-5p was a putative regulator of CTDSPL by luciferase reporter assay. Inhibition of miR-18a-5p promoted the expression of CTDSPL and induced premature senescence of MSCs. Continuous overexpression of miR-18a-5p improved self-renewal of MSCs by reducing ROS level, increased expression of Oct4 and Nanog, and promoted growth rate and differentiation capability. We reported for the first time that the dynamic interaction of miR-18a-5p and CTDSPL is crucial for stem cell senescence.

Long non-coding RNAs - SNHG6 emerge as potential marker in colorectal cancer

Colorectal cancer (CRC) ranks among the leading cancers in terms of incidence and mortality in the Western world. Currently, there are no sufficient diagnostic markers that would enable an early diagnosis and efficient therapy. Unfortunately, a significant number of new CRC cases is detected in late stages, with distant metastases, therefore, new therapeutic approaches, which would alleviate the prognosis for advanced stages of CRC, are highly in demand. SNHG6 belongs to the group of long non-coding RNAs, which are a larger entity of RNAs consisting of >200 nucleotides. SNHG6 is expressed mainly in the cell cytoplasm, where it acts as a regulator of numerous processes: modulation of crucial protein hubs; sponging miRNAs and upregulating the expression of their target mRNAs; and interacting with various cellular pathways including TGF-β/Smad and Wnt/β-catenin. SNHG6 is an oncogene, substantially overexpressed in CRC tissues and cancerous cell lines as compared to healthy samples. Its overexpression is associated with higher grade, lymphovascular invasion and tumor size. Taking into consideration the role of SNHG6 in the colorectal tumorigenesis, invasion and metastasis, we summarized its role in CRC and conclude that it could serve as a potential biomarker in CRC diagnosis and prognosis assessment.

LncRNA SNHG6 role in clinicopathological parameters in cancers

RNA sequencing has revealed that a substantial portion of the human genome undergoes transcription, yet a minimal fraction of these transcripts translates into proteins. LncRNAs, RNA molecules less than 200 nt in length, once deemed as transcriptional noise, have now emerged as crucial regulators of numerous cellular processes. This review focuses on the lncRNA SNHG6, aiming to elucidate its biogenesis, the pivotal roles it plays, and its mechanisms in facilitating the hallmarks of cancer. A comprehensive literature review and analysis were undertaken to delve into the biogenesis of SNHG6, its roles in cellular processes, and the mechanisms through which it contributes to the hallmarks of cancer. SNHG6 is a notable lncRNA, observed to be overexpressed in various cancer types; its perturbation has been linked to tumor progression, emphasizing its significance in oncogenesis. This lncRNA contributes to a range of cellular aberrations, influencing transcriptional, post-transcriptional, and epigenetic processes of mRNA, ultimately driving cancerous transformations. LncRNA SNHG6 serves as a potential biomarker and therapeutic target due to its association with tumorigenesis. Understanding its mechanism and role in cancer can pave the way for novel diagnostic and therapeutic strategies.

Double-edged sword role of miRNA-633 and miRNA-181 in human cancers

Understanding the function and mode of operation of microRNAs (miRNAs) in cancer is of growing interest. The short non-coding RNAs known as miRNAs, which target mRNA in multicellular organisms, are described as controlling essential cellular processes. The miR-181 family and miR-633 are well-known miRNAs that play a key role in the development and metastasis of tumor cells. They may facilitate either tumor-suppressive or oncogenic function in malignant cells, according to mounting evidence. Metastatic cells that are closely linked to cancer cell migration, invasion, and angiogenesis can be identified by abnormal levels of miR-181 and miR-633. Numerous studies have demonstrated their capacity to control drug resistance, cell growth, apoptosis, and the epithelial-mesenchymal transition (EMT) and metastasis process. Interestingly, the levels of miR-181 and miR-633 and their potential target genes in the basic cellular process can vary depending on the type of cancer cells and their gene expression profile. Such miRNAs' interactions with other non-coding RNAs such as long non-coding RNAs and circular RNAs can influence tumor behaviors. Herein, we concentrated on the multifaceted roles of miR-181 and miR-633 and potential targets in human tumorigenesis, ranging from cell growth and metastasis to drug resistance.

Long noncoding RNA SNHG6 silencing sensitized esophageal cancer cells to 5-FU via EZH2/STAT pathway

Chemotherapy was the main treatment method for esophageal cancer (EC) patients. However, chemotherapy resistance due to multiple factors is a major barrier to EC treatment. For investigating how small nucleolar RNA host gene 6 (SNHG6) affected the 5-fluorouracil (5-FU) resistance in EC as well as its possible molecular mechanism. This work conducted cell viability assay, clone formation, scratch assays together with cell apoptosis for evaluating the roles of SNHG6 and enhancer of zeste homolog 2 (EZH2, the histone-lysine N-methyltransferase). Relevant molecular mechanism was identified by RT-qPCR analysis together with Western-blot (WB) assays. Our data showed that SNHG6 expression increased in EC cells. SNHG6 promotes colony formation and migration, whereas suppresses EC cell apoptosis. SNHG6 silencing markedly promoted 5-FU-mediated suppression on KYSE150 and KYSE450 cells. Additional mechanism studies showed that SNHG6 modulating STAT3 and H3K27me3 via promoting EZH2 level. Similar to the function of SNHG6, abnormal expression of EZH2 promotes the malignancy of EC and intensifies its resistance to 5-FU. In addition, overexpression of EZH2 abolished the role of SNHG6 silencing in 5-FU sensitivity in EC cells. SNHG6 overexpression promoted malignancy of EC and increased EC cell resistance to 5-FU. Besides, further molecular mechanism studies provided a novel regulatory pathways that SNHG6 knockdown promoted EC cell sensitivity to 5-FU by modulating STAT3 and H3K27me3 via promoting EZH2 expression.

Association between small nucleolar RNA host gene expression and survival outcome of colorectal cancer patients: A meta-analysis based on PRISMA and bioinformatics analysis

Introduction

Growing evidence shows that long non-coding RNA small nucleolar RNA host genes (lncRNA SNHGs) enact an pivotal regulatory roles in the shorter survival outcome of colorectal cancer (CRC). However, no research has systematically evaluated the correlation among lncRNA SNHGs expression and survival outcome of CRC. This research indented to screen whether exist potential prognostic effect of lncRNA SNHGs in CRC patientss using comprehensive review and meta-analysis.

Methods

Systematic searches were performed from the six relevant databases from inception to October 20, 2022. The quality of published papers was evaluated in details. We pooled the hazard ratios (HR) with 95% confidence interval (CI) through direct or indirect collection of effect sizes, and odds ratios (OR) with 95% CI by collecting effect sizes within articles. Detailed downstream signaling pathways of lncRNA SNHGs were summarized in detail.

Results

25 eligible publications including 2,342 patients were finally included to appraise the association of lncRNA SNHGs with prognosis of CRC. Elevated lncRNA SNHGs expression was revealed in colorectal tumor tissues. High lncSNHG expression means bad survival prognosis in CRC patients (HR=1.635, 95% CI: 1.405-1.864, P<0.001). Additionally, high lncRNA SNHGs expression was inclined to later TNM stage (OR=1.635, 95% CI: 1.405-1.864, P<0.001), distant lymph node invasion, distant organ metastasis, larger tumor diameter and poor pathological grade. Begg's funnel plot test using the Stata 12.0 software suggested that no significant heterogeneity was found.

Conclusion

Elevated lncRNA SNHGs expression was revealed to be positively correlated to discontented CRC clinical outcome and lncRNA SNHG may act as a potential clinical prognostic index for CRC patients.

miR-181a/b downregulation: a mutation-independent therapeutic approach for inherited retinal diseases

Inherited retinal diseases (IRDs) are a group of diseases whose common landmark is progressive photoreceptor loss. The development of gene-specific therapies for IRDs is hampered by their wide genetic heterogeneity. Mitochondrial dysfunction is proving to constitute one of the key pathogenic events in IRDs; hence, approaches that enhance mitochondrial activities have a promising therapeutic potential for these conditions. We previously reported that miR-181a/b downregulation boosts mitochondrial turnover in models of primary retinal mitochondrial diseases. Here, we show that miR-181a/b silencing has a beneficial effect also in IRDs. In particular, the injection in the subretinal space of an adeno-associated viral vector (AAV) that harbors a miR-181a/b inhibitor (sponge) sequence (AAV2/8-GFP-Sponge-miR-181a/b) improves retinal morphology and visual function both in models of autosomal dominant (RHO-P347S) and of autosomal recessive (rd10) retinitis pigmentosa. Moreover, we demonstrate that miR-181a/b downregulation modulates the level of the mitochondrial fission-related protein Drp1 and rescues the mitochondrial fragmentation in RHO-P347S photoreceptors. Overall, these data support the potential use of miR-181a/b downregulation as an innovative mutation-independent therapeutic strategy for IRDs, which can be effective both to delay disease progression and to aid gene-specific therapeutic approaches.

Circulating lncRNA- and miRNA-Associated ceRNA Network as a Potential Prognostic Biomarker for Non-Hodgkin Lymphoma: A Bioinformatics Analysis and a Pilot Study

Non-Hodgkin lymphoma (NHL) is characterized by a great variability in patient outcomes, resulting in the critical need for identifying new molecular prognostic biomarkers. This study aimed to identify novel circulating prognostic biomarkers based on an miRNA/lncRNA-associated ceRNA network for NHL. Using bioinformatic analysis, we identified the miRNA-lncRNA pairs, and using RT-qPCR, we analyzed their plasma levels in a cohort of 113 NHL patients to assess their prognostic value. Bioinformatic analysis identified SNHG16 and SNHG6 as hsa-miR-20a-5p and hsa-miR-181a-5p sponges, respectively. Plasma levels of hsa-miR-20a-5p/SNHG16 and hsa-miR-181a-5p/SNG6 were significantly associated with more aggressive disease and IPI/FLIPI scores. Moreover, we found that patients with risk expression profiles of hsa-miR-20a-5p/SNHG16 and hsa-miR-181a-5p/SNHG6 presented a higher risk of positive bone marrow involvement. Moreover, hsa-miR-20a-5p/SNHG16 and hsa-miR-181a-5p/SNHG6 pairs’ plasma levels were associated with overall survival and progression-free survival of NHL patients, being independent prognostic factors in a multivariate Cox analysis. The prediction models incorporating the ceRNA network expression analysis improved the predictive capacity compared to the model, which only considered the clinicopathological variables. There are still few studies on using the ceRNA network as a potential prognostic biomarker, particularly in NHL, which may permit the implementation of a more personalized management of these patients.

Mucin 16 Promotes Colorectal Cancer Development and Progression Through Activation of Janus Kinase 2

BACKGROUND

Mucin 16 (MUC16), a cell surface-associated mucin, has been implicated to be upregulated in a large repertoire of malignances. However, its function in the pathogenesis of colorectal cancer (CRC) is unknown.

AIMS

Here, we explored the regulatory role of MUC16 in CRC.

METHODS

First, tumor and paracancerous tissues, and serum samples from 162 CRC patients, peripheral blood samples from 48 healthy volunteers and 72 benign colorectal patients were collected. The correlation between the MUC16 expression and the clinical phenotypes of the patients was analyzed. Subsequently, HCT116 and SW480 cells with deletion of MUC16 were established to detect changes in the growth and metastatic capacities of CRC cells. The genes with the highest correlation with MUC16 were predicted by bioinformatics, and their binding relationships were detected by Co-IP and double-labeled immunofluorescence, followed by functional rescue experiments.

RESULTS

Overexpression of MUC16 in CRC patients was positively correlated with serum biomarkers and poor prognosis of patients. It was demonstrated by in vitro and in vivo experiments that knocking-down the expression of MUC16 could significantly inhibit the growth and metastasis of CRC cells. MUC16 activated janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) by interacting with JAK2. Further overexpression of JAK2 in cells with poor expression of MUC16 revealed a significant increase in the proliferative and metastatic capacities of CRC cells.

CONCLUSIONS

MUC16 contributes to the development and progression of CRC by binding to JAK2, thereby promoting phosphorylation of JAK2 and further activating STAT3 phosphorylation.

Potentials of long non-coding RNAs as biomarkers of colorectal cancer

Colorectal cancer (CRC) is the third most common malignant tumor worldwide and the fourth major cause of cancer-related death, with high morbidity and increased mortality year by year. Although significant progress has been made in the therapy strategies for CRC, the great difficulty in early diagnosis, feeble susceptibility to radiotherapy and chemotherapy, and high recurrence rates have reduced therapeutic efficacy resulting in poor prognosis. Therefore, it is urgent to understand the pathogenesis of CRC and unravel novel biomarkers to improve the early diagnosis, treatment and prediction of CRC recurrence. Long non-coding RNAs (lncRNAs) are non-coding RNAs with a length of more than 200 nucleotides, which are abnormally expressed in tumor tissues and cell lines, activating or inhibiting specific genes through multiple mechanisms including transcription and translation. A growing number of studies have shown that lncRNAs are important regulators of microRNAs (miRNAs, miRs) expression in CRC and may be promising biomarkers and potential therapeutic targets in the research field of CRC. This review mainly summarizes the potential application value of lncRNAs as novel biomarkers in CRC diagnosis, radiotherapy, chemotherapy and prognosis. Additionally, the significance of lncRNA SNHGs family and lncRNA-miRNA networks in regulating the occurrence and development of CRC is mentioned, aiming to provide some insights for understanding the pathogenesis of CRC and developing new diagnostic and therapeutic strategies.

LncRNA LINC01535 promotes colorectal cancer development and chemoresistance by sponging miR-761

Colorectal cancer (CRC) is one of the most common human cancer types and a leading cause of cancer-related death. Accumulating evidence has confirmed that long non-coding RNAs have crucial roles in CRC progression. In the present study, the biological roles of LINC01535 were investigated and the interaction between long intergenic non-coding RNA (LINC)01535 and microRNA (miR)-761 in CRC was explored. LINC01535 expression was observed to be upregulated in CRC tissues and cell lines. A functional study suggested that LINC01535 silencing inhibited CRC cell proliferation and invasion but enhanced cisplatin sensitivity of CRC cells, while co-transfection with a miR-761 inhibitor reversed these biological effects. A luciferase reporter assay demonstrated that LINC01535 regulated miR-761 directly and RNA-binding protein immunoprecipitation further confirmed that the suppression of LINC01535 by miR-761 was via an RNA-induced silencing complex. Finally, knockdown of LINC01535 inhibited the growth of CRC cells in vivo. Collectively, the results suggested that LINC01535 exerts oncogenic functions in CRC by sponging miR-761. In conclusion, the present study indicated that LINC01535 promoted CRC progression through sponging miR-761, and may serve as a potential diagnostic biomarker and therapeutic target for CRC.

LINC01224 Promotes Colorectal Cancer Progression by Sponging miR-2467

Introduction

Colorectal cancer (CRC) is one of the most common human cancers and a leading cause of cancer-related death. Accumulating evidence has confirmed that long non-coding RNA (lncRNA) plays crucial roles in CRC development.

Methods

qRT-PCR was performed to examine the expressions of LINC01224 and miR-2467. CCK-8 assay, colony formation assay and transwell invasion assay were used to examine the progression of breast cancer cells. Luciferase and RNA-binding protein immunoprecipitation (RIP) assay were applied to verify the binding site. Correlation analysis of miR-2467 and LINC01224 expression in lung cancer tissues was shown. Pancreatic cancer cells growth in vivo was evaluated using xenograft tumor assay.

Results

LINC01224 expression was observed to be up-regulated in CRC tissues and cell lines. Functional studies suggested that LINC01224 silence inhibited CRC cells proliferation and invasion of CRC cells, while co-transfection with a miR-2467 inhibitor reversed these biological effects. Luciferase reporter assays illustrated that LINC01224 regulated miR-2467 directly, and RNA-binding protein immunoprecipitation (RIP) further confirmed that the suppression of LINC01224 by miR-2467 was in an RISC-dependent manner. Finally, LINC01224 silence inhibited the growth CRC cells in vivo.

Conclusion

In conclusion, our findings showed that LINC01224 promoted CRC progression through sponging miR-2467. LINC01224 may serve as a potential diagnostic biomarker and therapeutic target for CRC patients.