The noncoding MIR100HG RNA enhances the autocrine function of transforming growth factor β signaling

Exosomal lncRNA Mir100hg derived from cancer stem cells enhance glycolysis and promote metastasis of melanoma through miR-16-5p and miR-23a-3p

Increasing evidence demonstrate that the significant role of long non-coding RNA (lncRNA) in metastasis and the remodeling of the tumor microenvironment. However, the precise mechanisms of lncRNAs in cancer metastasis are still poorly understood. The function of lncRNA-Mir100hg in melanoma and its involvement in mediating communication between tumor stem cells and non-stemness tumor cells remains unknown. We found that Mir100hg is upregulated in melanoma stem cells (CSCs) known as OLSD. Furthermore, Mir100hg can be transferred from OLSD to non-stem cancer cells (OL) through exosomes. Once Mir100hg enters OL cells, it operates through a competitive endogenous RNA (ceRNA) mechanism. It competes with microRNAs (miR-16-5p and miR-23a-3p) by binding to them, thus preventing these miRNAs from targeting their mRNAs. As a result, the expression of glycolysis-related mRNA was restored. This ultimately enhances the metastatic capability of OL cells. In summary, our study uncovers a network used by CSCs to transfer their high metastatic activity to non-stem cancer cells through the exosomal Mir100hg. This mechanism sheds new light on the communication between heterogeneous cancer cell populations in melanoma. Importantly, it provides novel insights into the role of lncRNAs in cancer metastasis and highlights the significance of the tumor microenvironment in facilitating metastasis.

RNA regulatory mechanisms controlling TGF-β signaling and EMT in cancer

Epithelial-mesenchymal transition (EMT) is a major contributor to metastatic progression and is prominently regulated by TGF-β signalling. Both EMT and TGF-β pathway components are tightly controlled by non-coding RNAs - including microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) - that collectively have major impacts on gene expression and resulting cellular states. While miRNAs are the best characterised regulators of EMT and TGF-β signaling and the miR-200-ZEB1/2 feedback loop plays a central role, important functions for lncRNAs and circRNAs are also now emerging. This review will summarise our current understanding of the roles of non-coding RNAs in EMT and TGF-β signaling with a focus on their functions in cancer progression.

A novel TGFbeta/TGILR axis mediates crosstalk between cancer-associated fibroblasts and tumor cells to drive gastric cancer progression

Transforming growth factor beta (TGFβ) signaling plays a critical role in tumorigenesis and metastasis. However, little is known about the biological function of TGFbeta-induced lncRNA in cancer. In this study, we discovered a novel TGFbeta-induced lncRNA, termed TGILR, whose function in cancer remains unknown to date. TGILR expression was directly activated by the canonical TGFbeta/SMAD3 signaling axis, and this activation is highly conserved in cancer. Clinical analysis showed that TGILR overexpression showed a significant correlation with lymph node metastasis and poor survival and was an independent prognostic factor in gastric cancer (GC). Depletion of TGILR caused an obvious inhibitory effect on GC cell proliferation, invasion, and epithelial-mesenchymal transition (EMT) in vitro and in vivo. More importantly, we demonstrated that TGFbeta signaling in GC was overactivated due to cancer-associated fibroblast (CAF) infiltration. Mechanistically, increased level of CAF-secreted TGFbeta activates TGFbeta signaling, leading to TGILR overexpression in GC cells. Meanwhile, TGILR overexpression inhibited the microRNA biogenesis of miR-1306 and miR-33a by interacting with TARBP2 and reducing its protein stability, thereby promoting GC progression via TCF4-mediated EMT signaling. In conclusion, CAF infiltration drives GC metastasis and EMT signaling through activating TGFbeta/TGILR axis. Targeted blocking of CAF-derived TGFbeta should be a promising anticancer strategy in GC.

Unboxing the network among long non-coding RNAs and TGF-β signaling in cancer

Deeper analysis of molecular mechanisms arising in tumor cells is an unmet need to provide new diagnostic and therapeutic strategies to prevent and treat tumors. The transforming growth factor β (TGF-β) signaling has been steadily featured in tumor biology and linked to poor prognosis of cancer patients. One pro-tumorigenic mechanism induced by TGF-β is the epithelial-to-mesenchymal transition (EMT), which can initiate cancer dissemination, enrich the tumor stem cell population, and increase chemoresistance. TGF-β signals via SMAD proteins, ubiquitin ligases, and protein kinases and modulates the expression of protein-coding and non-coding RNA genes, including those encoding larger than 500 nt transcripts, defined as long non-coding RNAs (lncRNAs). Several reports have shown lncRNAs regulating malignant phenotypes by directly affecting epigenetic processes, transcription, and post-transcriptional regulation. Thus, this review aims to update and summarize the impact of TGF-β signaling on the expression of lncRNAs and the function of such lncRNAs as regulators of TGF-β signaling, and how these networks might impact specific hallmarks of cancer.

miRNA profiling of esophageal adenocarcinoma using transcriptome analysis

Esophageal adenocarcinoma (EAC) occurs following a series of histological changes through epithelial-mesenchymal transition (EMT). A variable expression of normal and aberrant genes in the tissue can contribute to the development of EAC through the activation or inhibition of critical molecular signaling pathways. Gene expression is regulated by various regulatory factors, including transcription factors and microRNAs (miRs). The exact profile of miRs associated with the pathogenesis of EAC is largely unknown, though some candidate miRNAs have been reported in the literature. To identify the unique miR profile associated with EAC, we compared normal esophageal tissue to EAC tissue using bulk RNA sequencing. RNA sequence data was verified using qPCR of 18 selected genes. Fourteen were confirmed as being upregulated, which include CDH11, PCOLCE, SULF1, GJA4, LUM, CDH6, GNA12, F2RL2, CTSZ, TYROBP, and KDELR3 as well as the downregulation of UGT1A1. We then conducted Ingenuity Pathway Analysis (IPA) to analyze for novel miR-gene relationships through Causal Network Analysis and Upstream Regulator Analysis. We identified 46 miRs that were aberrantly expressed in EAC compared to control tissues. In EAC tissues, seven miRs were associated with activated networks, while 39 miRs were associated with inhibited networks. The miR-gene relationships identified provide novel insights into potentially oncogenic molecular pathways and genes associated with carcinogenesis in esophageal tissue. Our results revealed a distinct miR profile associated with dysregulated genes. The miRs and genes identified in this study may be used in the future as biomarkers and serve as potential therapeutic targets in EAC.

A pan-cancer analysis indicates long noncoding RNA HAND2-AS1 as a potential prognostic, immunomodulatory and therapeutic biomarker in various cancers including colorectal adenocarcinoma

The HAND2-AS1 (HAND2 Antisense RNA 1) Long noncoding RNA (lncRNA) has emerged as a participant in the initiation of various cancer types, underscoring its pivotal involvement in both oncological processes and immune responses. To gain deeper insights into the functional nuances of HAND2-AS1 and identify novel avenues for cancer immunotherapy, a comprehensive evaluation of this gene was undertaken. Here, based on the co-expression network analysis and construction of interacting lncRNA-mRNA genes, we introduce the HAND2-AS1 lncRNA, emphasizing its key roles in tumorigenesis and immune regulation. Our study spans across 33 distinct cancer types, revealing the HAND2-AS1's aberrant expression patterns, methylation variations, mutational signatures, and immune engagement. Across a majority of tumors, HAND2-AS1 exhibited a propensity for down-regulation, remarkably an association with poor survival outcomes. The outcomes of functional enrichment analyses strongly suggest HAND2-AS1's engagement in tumor progression and its association with various immune pathways across diverse tumor classifications. Additionally, a positive correlation emerged between HAND2-AS1 expression and the infiltration levels of key immune cells, encompassing not only immunosuppressive entities such as tumor-associated macrophages, cancer-associated fibroblasts, and Tregs, but also immune effector cells like NK cells and CD8+ T cells, spanning a pan-cancer context. Furthermore, the differential expression of HAND2-AS1 appears to have downstream consequences on various pathways, thus implicating it as a potential regulator in diverse cancer types. Finally, we have employed CRC tumor and normal samples to carry out clinical validation of HAND2-AS1. Our study unveils HAND2-AS1's potential as a pan-cancer tumor suppressor, and its essential role in the tumorigenesis and immune surveillance. The increased HAND2-AS1 expression emerges as a promising candidate for prognostic evaluation, therapeutic strategy, and a focal point for immunotherapeutic interventions.

The Role of the Transforming Growth Factor-β Signaling Pathway in Gastrointestinal Cancers

Transforming growth factor-β (TGF-β) has attracted attention as a tumor suppressor because of its potent growth-suppressive effect on epithelial cells. Dysregulation of the TGF-β signaling pathway is considered to be one of the key factors in carcinogenesis, and genetic alterations affecting TGF-β signaling are extraordinarily common in cancers of the gastrointestinal system, such as hereditary nonpolyposis colon cancer and pancreatic cancer. Accumulating evidence suggests that TGF-β is produced from various types of cells in the tumor microenvironment and mediates extracellular matrix deposition, tumor angiogenesis, the formation of CAFs, and suppression of the anti-tumor immune reaction. It is also being considered as a factor that promotes the malignant transformation of cancer, particularly the invasion and metastasis of cancer cells, including epithelial-mesenchymal transition. Therefore, elucidating the role of TGF-β signaling in carcinogenesis, cancer invasion, and metastasis will provide novel basic insight for diagnosis and prognosis and the development of new molecularly targeted therapies for gastrointestinal cancers. In this review, we outline an overview of the complex mechanisms and functions of TGF-β signaling. Furthermore, we discuss the therapeutic potentials of targeting the TGF-β signaling pathway for gastrointestinal cancer treatment and discuss the remaining challenges and future perspectives on targeting this pathway.

Exosomal lncRNA Mir100hg derived from cancer stem cells enhance glycolysis and promote metastasis of lung adenocarcinoma through mircroRNA-15a-5p/31-5p

BACKGROUND

Exosomes are a new class of molecular entities in the metastatic microenvironment, which can mediate bidirectional communication between cells. While exosomes-mediated interactions between tumor cells and other cell populations in the tumor microenvironment have attracted most attention, little is known about the significance of exosomes in mediating the interaction between non-stemness cancer cells and cancer stem cells during cancer progression.

METHODS

The structure, sequence and downstream target miRNAs of lncRNA Mir100hg were predicted by online web resources. The bioinformatics prediction results were validated with experimental verification: exosome tracing, electron microscopy, Luciferase assay, metabolomics sequencing and mouse tail vein model of pulmonary metastasis. A complex regulatory network of "cancer stem cells-exosomal lncRNA-non-stem cancer cells" was constructed.

RESULTS

This study demonstrates firstly that lncRNA Mir100hg is upregulated in lung cancer stem cell LLC-SD (Lung cancer stem cells) and can be delivered to non-stemness cancer cells LLC (Lewis lung cancer cells) via exosomes. In LLC, Mir100hg targets miR-15a-5p and miR-31-5p which leads to the increase of the global glycolytic activity of lung cancer cells and consequently, the enhancement of their metastatic capability.

CONCLUSION

We delineated a complex regulatory network that utilized by cancer stem cells to transfer their high metastatic activity to the low-metastatic non-stemness cancer cells through exosomal Mir100hg, thereby providing new mechanistic insights into the communication between two heterogeneous tumor cells. Video Abstract.

A distinct circular DNA profile intersects with proteome changes in the genotoxic stress-related hSOD1G93A model of ALS

BACKGROUND

Numerous genes, including SOD1, mutated in familial and sporadic amyotrophic lateral sclerosis (f/sALS) share a role in DNA damage and repair, emphasizing genome disintegration in ALS. One possible outcome of chromosomal instability and repair processes is extrachromosomal circular DNA (eccDNA) formation. Therefore, eccDNA might accumulate in f/sALS with yet unknown function.

METHODS

We combined rolling circle amplification with linear DNA digestion to purify eccDNA from the cervical spinal cord of 9 co-isogenic symptomatic hSOD1G93A mutants and 10 controls, followed by deep short-read sequencing. We mapped the eccDNAs and performed differential analysis based on the split read signal of the eccDNAs, referred as DifCir, between the ALS and control specimens, to find differentially produced per gene circles (DPpGC) in the two groups. Compared were eccDNA abundances, length distributions and genic profiles. We further assessed proteome alterations in ALS by mass spectrometry, and matched the DPpGCs with differentially expressed proteins (DEPs) in ALS. Additionally, we aligned the ALS-specific DPpGCs to ALS risk gene databases.

RESULTS

We found a six-fold enrichment in the number of unique eccDNAs in the genotoxic ALS-model relative to controls. We uncovered a distinct genic circulome profile characterized by 225 up-DPpGCs, i.e., genes that produced more eccDNAs from distinct gene sequences in ALS than under control conditions. The inter-sample recurrence rate was at least 89% for the top 6 up-DPpGCs. ALS proteome analyses revealed 42 corresponding DEPs, of which 19 underlying genes were itemized for an ALS risk in GWAS databases. The up-DPpGCs and their DEP tandems mainly impart neuron-specific functions, and gene set enrichment analyses indicated an overrepresentation of the adenylate cyclase modulating G protein pathway.

CONCLUSIONS

We prove, for the first time, a significant enrichment of eccDNA in the ALS-affected spinal cord. Our triple circulome, proteome and genome approach provide indication for a potential importance of certain eccDNAs in ALS neurodegeneration and a yet unconsidered role as ALS biomarkers. The related functional pathways might open up new targets for therapeutic intervention.

LncRNA CECR7 boosts hepatocellular carcinoma progression by recruiting RNA binding protein U2AF2 to enhance the stability of EXO1 mRNA

Objective

As an important factor tumor regulator，long non-coding RNAs (lncRNAs) have aroused extensive attention via the diverse functional mechanisms that were associated with the pathological and physiological processes of HCC. Here, the main purpose of this study was to provide a clear understanding about the expression, functions and potential mechanism of lncRNA CECR7 (Cat Eye Syndrome Chromosome Region, Candidate 7) in HCC.

Methods

RT-qPCR analysis and TCGA database analysis were applied to investigate the expression of CECR7 in HCC cell lines and tissues. Chi-squared Test was employed to explore the correlation between CECR7 expression and HCC clinicopathological features. Besides, Kaplan-Meier curves were constructed to test the effects of CECR7 expression on the prognosis of HCC patients. Transwell assays, MTT assay EdU assay and animal experiments were applied to explore the effects of CECR7 expression on HCC cells migration, invasion, and growth. Furthermore, RNA-seq analysis, luciferase reporter assay and mRNA decay rates assessment were utilized to investigate the mechanism whereby CECR7 regulated EXO1 mRNA. And, rescue experiments were used to determine whether EXO1 was an essential mediator for CECR7 to accelerate HCC cells migration, invasion, and growth.

Results

CECR7 was determined to be significantly overexpressed in HCC cell lines and tissues. CECR7 expression was closely correlated with the tumor size, venous infiltration, TNM stage, 5-year overall survival and disease-free survival of HCC. And, CECR7 played a catalytic role in HCC cells migration, invasion, and growth. Furthermore, CECR7 enhanced the stability of EXO1 mRNA by recruiting RNA binding protein U2AF2. And, EXO1 was determined to be an essential mediator for CECR7 to accelerate HCC cells migration, invasion, and growth.

Conclusion

In a word, our findings demonstrates that the cancer-promoting gene lncRNA CECR7 motivates HCC metastasis and growth through enhanced mRNA stability of EXO1 mediated by U2AF2, proposing a new insight for targeted therapy of HCC.

A concise review on the role of MIR100HG in human disorders

MIR100HG is a long non-coding RNA (lncRNA) encoded by a locus on chr11:122,028,203-122,556,721. This gene can regulate cell proliferation, apoptosis, cell cycle transition and cell differentiation. MIR100HG was firstly identified through a transcriptome analysis and found to regulate differentiation of human neural stem cells. It is functionally related with a number of signalling pathways such as TGF-β, Wnt, Hippo and ERK/MAPK signalling pathways. Dysregulation of MIR100HG has been detected in a diversity of cancers in association with clinical outcomes. Moreover, it has a role in the pathophysiology of dilated cardiomyopathy, intervertebral disk degeneration and pulmonary fibrosis. The current study summarizes the role of these lncRNAs in human disorders.

Roles of TGF‑β signalling pathway‑related lncRNAs in cancer (Review)

Long non-coding RNAs (lncRNAs) are a class of RNAs that are >200 nucleotides in length that do not have the ability to be translated into protein but are associated with numerous diseases, including cancer. The involvement of lncRNAs in the signalling of certain signalling pathways can promote tumour progression; these pathways include the transforming growth factor (TGF)-β signalling pathway, which is related to tumour development. The expression of lncRNAs in various tumour tissues is specific, and their interaction with the TGF-β signalling pathway indicates that they may serve as new tumour markers and therapeutic targets. The present review summarized the role of TGF-β pathway-associated lncRNAs in regulating tumorigenesis in different types of cancer and their effects on the TGF-β signalling pathway.

LncmiRHG-MIR100HG: A new budding star in cancer

MIR100HG, also known as lncRNA mir-100-let-7a-2-mir-125b-1 cluster host gene, is a new and critical regulator in cancers in recent years. MIR100HG is dysregulated in various cancers and plays an oncogenic or tumor-suppressive role, which participates in many tumor cell biology processes and cancer-related pathways. The errant expression of MIR100HG has inspired people to investigate the function of MIR100HG and its diagnostic and therapeutic potential in cancers. Many studies have indicated that dysregulated expression of MIR100HG is markedly correlated with poor prognosis and clinicopathological features. In this review, we will highlight the characteristics and introduce the role of MIR100HG in different cancers, and summarize the molecular mechanism, pathways, chemoresistance, and current research progress of MIR100HG in cancers. Furthermore, some open questions in this rapidly advancing field are proposed. These updates clarify our understanding of MIR100HG in cancers, which may pave the way for the application of MIR100HG-targeting approaches in future cancer diagnosis, prognosis, and therapy.

Promotion or remission: a role of noncoding RNAs in colorectal cancer resistance to anti-EGFR therapy

Anti-epidermal-growth-factor-receptor (EGFR) monoclonal antibodies (mAbs) are of great significance for RAS and BRAF wild-type metastatic colorectal cancer (mCRC) patients. However, the generation of primary and secondary resistance to anti-EGFR mAbs has become an important factor restricting its efficacy. Recent studies have revealed that non-coding RNAs (ncRNAs), especially long non-coding RNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs), are implicated in anti-EGFR antibodies resistance, affecting the sensitivity of CRC cells to Cetuximab and Panitumumab. This paper briefly reviewed the research advance of the expression, signaling network and functional mechanism of ncRNAs related to anti-EGFR mAbs resistance in CRC, as well as their relationship with clinical prognosis and the possibility of therapeutic targets. In addition, some ncRNAs that are involved in the regulation of signaling pathways or genes related to anti-EGFR resistance, but need to be further verified by resistance experiments were also included in this review, thereby providing more ideas and basis for ncRNAs as CRC prognostic markers and anti-EGFR therapy sensitizers. Video Abstract.

Transforming Growth Factor-Beta-Regulated LncRNA-MUF Promotes Invasion by Modulating the miR-34a Snail1 Axis in Glioblastoma Multiforme

Transforming growth factor beta (TGF-β)-regulated long-non-coding RNAs (lncRNAs) modulate several aspects of tumor development such as proliferation, invasion, metastasis, epithelial to mesenchymal transition (EMT), and drug resistance in various cancers, including Glioblastoma multiforme (GBM). We identified several novel differentially expressed lncRNAs upon TGF-β treatment in glioma cells using genome-wide microarray screening. We show that TGF-β induces lncRNA-MUF in glioma cells, and its expression is significantly upregulated in glioma tissues and is associated with poor overall survival of GBM patients. Knockdown of lncRNA-MUF reduces proliferation, migration, and invasion in glioma cells and sensitizes them to temozolomide (TMZ)-induced apoptosis. In addition, lncRNA-MUF downregulation impairs TGF-β-induced smad2/3 phosphorylation. In line with its role in regulating invasion, lncRNA-MUF functions as a competing endogenous RNA (ceRNA) for miR-34a and promotes Snail1 expression. Collectively, our findings suggest lncRNA-MUF as an attractive therapeutic target for GBM.

Transforming growth factor β latency: A mechanism of cytokine storage and signalling regulation in liver homeostasis and disease

Transforming growth factor-β (TGF-β) is a potent effector in the liver, which is involved in a plethora of processes initiated upon liver injury. TGF-β affects parenchymal, non-parenchymal, and inflammatory cells in a highly context-dependent manner. Its bioavailability is critical for a fast response to various insults. In the liver – and probably in other organs – this is made possible by the deposition of a large portion of TGF-β in the extracellular matrix as an inactivated precursor form termed latent TGF-β (L-TGF-β). Several matrisomal proteins participate in matrix deposition, latent complex stabilisation, and activation of L-TGF-β. Extracellular matrix protein 1 (ECM1) was recently identified as a critical factor in maintaining the latency of deposited L-TGF-β in the healthy liver. Indeed, its depletion causes spontaneous TGF-β signalling activation with deleterious effects on liver architecture and function. This review article presents the current knowledge on intracellular L-TGF-β complex formation, secretion, matrix deposition, and activation and describes the proteins and processes involved. Further, we emphasise the therapeutic potential of toning down L-TGF-β activation in liver fibrosis and liver cancer.