Long non-coding RNA H19 promotes glucose metabolism and cell growth in malignant melanoma via miR-106a-5p/E2F3 axis

Exosomal miR-19a derived from melanoma cell promotes the vemurafenib resistance of malignant melanoma through directly targeting LRIG1 to reactivate AKT and MAPK pathway

Exosomes derived from neighboring v-raf murine sarcoma viral oncogene homolog B1 inhibitor (BRAFi)-resistant melanoma cells mediate the formation of resistance in melanoma cells sensitive to BRAFi. The function and molecular mechanisms of exosomal miRNA in BRAFi resistance of melanoma have not been studied. We found that the expression of miR-19a in BRAFi resistant melanoma cells was significantly higher than that in sensitive cells, and miR-19a contributes to the resistance of melanoma cells to BRAFi by targeting immunoglobulin-like domains protein 1 (LRIG1). miR-19a was highly enriched in exosomes secreted from BRAFi resistant melanoma cells, and these exosomal miR-19a promote the spread of BRAFi resistant. The reactivation of Protein kinase B (AKT) and mitogen-activated protein kinase (MAPK) pathways is the main reason for the BRAFi resistant of melanoma cells. We demonstrated that exosomal miR-19a derived from melanoma cell promotes the formation and spread of BRAFi resistant in melanoma through targeting LRIG1 to reactivate AKT and MAPK pathway. Therefore, miR-19a may serve as a potential therapeutic target in melanoma patients with acquired drug resistance.

β-Elemene Reverses Gefitinib Resistance in NSCLC Cells by Inhibiting lncRNA H19-Mediated Autophagy

Lung cancer is a leading cause of mortality worldwide, especially among Asian patients with non-small cell lung cancer (NSCLC) who have epidermal growth factor receptor (EGFR) mutations. Initially, first-generation EGFR tyrosine kinase inhibitors (TKIs) are commonly administered as the primary treatment option; however, encountering resistance to these medications poses a significant obstacle. Hence, it has become crucial to address initial resistance and ensure continued effectiveness. Recent research has focused on the role of long noncoding RNAs (lncRNAs) in tumor drug resistance, especially lncRNA H19. β-elemene, derived from Curcuma aromatic Salisb., has shown strong anti-tumor effects. However, the relationship between β-elemene, lncRNA H19, and gefitinib resistance in NSCLC is unclear. This study aims to investigate whether β-elemene can enhance the sensitivity of gefitinib-resistant NSCLC cells to gefitinib and to elucidate its mechanism of action. The impact of gefitinib and β-elemene on cell viability was evaluated using the cell counting kit-8 (CCK8) assay. Furthermore, western blotting and qRT-PCR analysis were employed to determine the expression levels of autophagy-related proteins and genes, respectively. The influence on cellular proliferation was gauged through a colony-formation assay, and apoptosis induction was quantified via flow cytometry. Additionally, the tumorigenic potential in vivo was assessed using a xenograft model in nude mice. The expression levels of LC3B, EGFR, and Rab7 proteins were examined through immunofluorescence. Our findings elucidate that the resistance to gefitinib is intricately linked with the dysregulation of autophagy and the overexpression of lncRNA H19. The synergistic administration of β-elemene and gefitinib markedly attenuated the proliferative capacity of resistant cells, expedited apoptotic processes, and inhibited the in vivo proliferation of lung cancer. Notably, β-elemene profoundly diminished the expression of lncRNA H19 and curtailed autophagic activity in resistant cells, thereby bolstering their responsiveness to gefitinib. Moreover, β-elemene disrupted the Rab7-facilitated degradation pathway of EGFR, facilitating its repositioning to the plasma membrane. β-elemene emerges as a promising auxiliary therapeutic for circumventing gefitinib resistance in NSCLC, potentially through the regulation of lncRNA H19-mediated autophagy. The participation of Rab7 in this dynamic unveils novel insights into the resistance mechanisms operative in lung cancer, paving the way for future therapeutic innovations.

Downregulation of lncRNA MIR17HG reduced tumorigenicity and Treg-mediated immune escape of non-small-cell lung cancer cells through targeting the miR-17-5p/RUNX3 axis

Long noncoding RNA MIR17HG was involved with the progression of non-small-cell lung cancer (NSCLC), but specific mechanisms of MIR17HG-mediated immune escape of NSCLC cells were still unknown. The present study investigated the function of MIR17HG on regulatory T cell (Treg)-mediated immune escape and the underlying mechanisms in NSCLC. Expression of MIR17HG and miR-17-5p in NSCLC tissue samples were detected using quantitative real-time PCR (qRT-PCR). A549 and H1299 cells were transfected with sh-MIR17HG, miR-17-5p inhibitor, or sh-MIR17HG + miR-17-5p inhibitor, followed by cocultured with Tregs. Cell proliferation was measured using 5-ethynyl-20-deoxyuridine (Edu) staining assay and cell counting kit-8 (CCK-8) assay. Flow cytometry was used for determining positive numbers of FOXP3+CD4+/CD25+/CD8+ Tregs. Through subcutaneous injection with transfected A549 cells, a xenograft nude mouse model was established. Weights and volumes of xenograft tumors were evaluated. Additionally, the expressions of immune-related factors including transforming growth factor beta (TGF-β), vascular endothelial growth factor A (VEGF-A), interleukin-10 (IL-10), IL-4, and interferon-gamma (IFN-γ) in cultured cells, were evaluated by enzyme-linked immunosorbent assay and western blot analysis. Then, miR-17-5p was decreased and MIR17HG was enhanced in both NSCLC tissues and cell lines. MIR17HG knockdown significantly suppressed cell proliferation, tumorigenicity, and immune capacity of Tregs in A549 and H1299 cells, whereas sh-MIR17HG significantly reduced expression levels of VEGF-A, TGF-β, IL-4, and IL-10 but promoted the IFN-γ level in vitro and in vivo. Moreover, downregulation of miR-17-5p significantly reversed the effects of sh-MIR17HG. Additionally, we identified that runt- related transcription factor 3 (RUNX3) was a target of miR-17-5p, and sh-MIR17HG and miR-17-5p mimics downregulated RUNX3 expression. In conclusion, downregulation of MIR17HG suppresses tumorigenicity and Treg-mediated immune escape in NSCLC through downregulating the miR-17-5p/RUNX3 axis, indicating that this axis contains potential biomarkers for NSCLC.

circRNA-PTPN4 mediated regulation of FOXO3 and ZO-1 expression: implications for blood-brain barrier integrity and cognitive function in uremic encephalopathy

Uremic encephalopathy (UE) poses a significant challenge in neurology, leading to the need to investigate the involvement of non-coding RNA (ncRNA) in its development. This study employed ncRNA-seq and RNA-seq approaches to identify fundamental ncRNAs, specifically circRNA and miRNA, in the pathogenesis of UE using a mouse model. In vitro and in vivo experiments were conducted to explore the circRNA-PTPN4/miR-301a-3p/FOXO3 axis and its effects on blood-brain barrier (BBB) function and cognitive abilities. The research revealed that circRNA-PTPN4 binds to and inhibits miR-301a-3p, leading to an increase in FOXO3 expression. This upregulation results in alterations in the transcriptional regulation of ZO-1, affecting the permeability of human brain microvascular endothelial cells (HBMECs). The axis also influences the growth, proliferation, and migration of HBMECs. Mice with UE exhibited cognitive deficits, which were reversed by overexpression of circRNA-PTPN4, whereas silencing FOXO3 exacerbated these deficits. Furthermore, the uremic mice showed neuronal loss, inflammation, and dysfunction in the BBB, with the expression of circRNA-PTPN4 demonstrating therapeutic effects. In conclusion, circRNA-PTPN4 plays a role in promoting FOXO3 expression by sequestering miR-301a-3p, ultimately leading to the upregulation of ZO-1 expression and restoration of BBB function in mice with UE. This process contributes to the restoration of cognitive abilities.

Diagnostic and prognostic role of long non-coding RNAs (lncRNAs) in metastatic melanoma patients with BRAF gene mutation receiving BRAF and MEK inhibitors

Melanoma is a cancer with a high incidence rate that, despite the significant development of therapeutic options, still remains a major problem. The identification of biomarkers to select the right therapy for the right patient is one of the possibilities to improve the prognosis of patients. Potentially, the function of biomarkers could be played long non-coding RNAs (lncRNAs). The expression of selected 90 lncRNAs in serum from 30 metastatic melanoma patients with confirmed mutations in the BRAF V600 E or K gene was studied. Serum was collected prior to BRAF and MEK inhibitor therapy. The control group consisted of 16 healthy volunteers. A total of 41 lncRNAs were identified the expression of which differed statistically significantly between the patient group and the healthy volunteers. In addition, it was shown that the expression of HOXA3as (p = 0.033), PRINS (p = 0.036) and RNCR3 (p = 0.045) is higher in patients with the presence of CNS metastases, PFS inhibiting RNA (p = 0.048) is higher among patients with the presence of hepatic metastases, UCA1 (p = 0.008) expression is lower in patients with increased lactate dehydrogenase levels, while HOTAIRM1 (p = 0.044) and E2F4 antisense (p = 0.040) expression is lower in patients over 60 years of age. In addition, patients with high lincRNASFMBT2 expression showed longer median PFS (8.75 vs. 17.5 months, p = 0.0319) and OS (9.75 vs. 38 months (open observation, p = 0.0253). The obtained results require validation on a larger group of patients. If the results are confirmed, the indicated lncRNAs may play an important role as diagnostic and prognostic markers.

LncRNA AGAP2 antisense RNA 1 stabilized by insulin-like growth factor 2 mRNA binding protein 3 promotes macrophage M2 polarization in clear cell renal cell carcinoma through regulation of the microRNA-9-5p/THBS2/PI3K-Akt pathway

BACKGROUND

Increasing evidence highlights the potential role of long non-coding RNAs (lncRNAs) in the biological behaviors of renal cell carcinoma (RCC). Here, we explored the mechanism of AGAP2-AS1 in the occurrence and development of clear cell RCC (ccRCC) involving IGF2BP3/miR-9-5p/THBS2.

METHODS

The expressions of AGAP2-AS1, IGF2BP3, miR-9-5p, and THBS2 and their relationship were analyzed by bioinformatics. The targeting relationship between AGAP2-AS1 and miR-9-5p and between miR-9-5p and THBS2 was evaluated with their effect on cell biological behaviors and macrophage polarization assayed. Finally, we tested the effect of AGAP2-AS1 on ccRCC tumor formation in xenograft tumors.

RESULTS

IGF2BP3 could stabilize AGAP2-AS1 through m6A modification. AGAP2-AS1 was highly expressed in ccRCC tissues and cells. The lentivirus-mediated intervention of AGAP2-AS1 induced malignant behaviors of ccRCC cells and led to M2 polarization of macrophages. In addition, THBS2 promoted M2 polarization of macrophages by activating the PI3K/AKT signaling pathway. AGAP2-AS1 could directly bind with miR-9-5p and promote the expression of THBS2 downstream of miR-9-5p. These results were further verified by in vivo experiments.

CONCLUSION

AGAP2-AS1 stabilized by IGF2BP3 competitively binds to miR-9-5p to up-regulate THBS2, activating the PI3K/AKT signaling pathway and inducing macrophage M2 polarization, thus facilitating the development of RCC.

Overview of miR-106a Regulatory Roles: from Cancer to Aging

MicroRNAs (miRNAs) comprise a class of non-coding RNA with extensive regulatory functions within cells. MiR-106a is recognized for its super-regulatory roles in vital processes. Hence, the analysis of its expression in association with diseases has attracted considerable attention for molecular diagnosis and drug development. Numerous studies have investigated miR-106 target genes and shown that this miRNA regulates the expression of some critical cell cycle and apoptosis factors, suggesting miR-106a as an ideal diagnostic and prognostic biomarker with therapeutic potential. Furthermore, the reported correlation between miR-106a expression level and cancer drug resistance has demonstrated the complexity of its functions within different tissues. In this study, we have conducted a comprehensive review on the expression levels of miR-106a in various cancers and other diseases, emphasizing its target genes. The promising findings surrounding miR-106a suggest its potential as a valuable biomolecule. However, further validation assessments and overcoming existing limitations are crucial steps before its clinical implementation can be realized.

Insights into the Role of LncRNAs and miRNAs in Glioma Progression and Their Potential as Novel Therapeutic Targets

Accumulating evidence supports that both long non-coding and micro RNAs (lncRNAs and miRNAs) are implicated in glioma tumorigenesis and progression. Poor outcome of gliomas has been linked to late-stage diagnosis and mostly ineffectiveness of conventional treatment due to low knowledge about the early stage of gliomas, which are not possible to observe with conventional diagnostic approaches. The past few years witnessed a revolutionary advance in biotechnology and neuroscience with the understanding of tumor-related molecules, including non-coding RNAs that are involved in the angiogenesis and progression of glioma cells and thus are used as prognostic biomarkers as well as novel therapeutic targets. The emerging research on lncRNAs and miRNAs highlights their crucial role in glioma progression, offering new insights into the disease. These non-coding RNAs hold significant potential as novel therapeutic targets, paving the way for innovative treatment approaches against glioma. This review encompasses a comprehensive discussion about the role of lncRNAs and miRNAs in gene regulation that is responsible for the promotion or the inhibition of glioma progression and collects the existing links between these key cancer-related molecules.

Emerging role of oncogenic long noncoding RNA as cancer biomarkers

The view of long noncoding RNAs as nonfunctional "garbage" has been definitely outdated by the large body of evidence indicating this class of ncRNAs as "golden junk", especially in precision oncology. Indeed, in light of their oncogenic role and the higher expression in multiple cancer types compared with paired adjacent tissues, the clinical interest for lncRNAs as diagnostic and/or prognostic biomarkers has been rapidly increasing. The emergence of large-scale sequencing technologies, their subsequent diffusion even in small research and clinical centers, the technological advances for the detection of low-copy lncRNAs in body fluids, coupled to the huge reduction of operating costs, have nowadays made possible to rapidly and comprehensively profile them in multiple tumors and large cohorts. In this review, we first summarize some relevant data about the oncogenic role of well-studied lncRNAs having a clinical relevance. Then, we focus on the description of their potential use as diagnostic/prognostic biomarkers, including an updated overview about licensed patents or clinical trials on lncRNAs in oncology.

Long non-coding RNAs and melanoma: From diagnosis to therapy

Although extremely rare, malignant melanoma is the deadliest type of skin malignancy with the inherent capability to invade other organs and metastasize to distant tissues. In 2021, it was estimated that approximately 106,110 patients may have received the diagnosis of melanoma, with a mortality rate of 7180. Surgery remains the common choice for treatment in patients with melanoma. Despite many advances in the treatment of melanoma, some patients, such as those who have received cytotoxic chemotherapeutic and immunotherapic agents, a significant number of patients may show inadequate treatment response following initiating these treatments. Non-coding RNAs, including lncRNAs, have become recently popular and attracted the attention of many researchers to make new insights into the pathogenesis of many diseases, particularly malignancies. LncRNAs have been thoroughly investigated in multiple cancers such as melanoma and have been shown to play a major role in regulating various physiological and pathological cellular processes. Considering their core regulatory function, these non-coding RNAs may be appropriate candidates for melanoma patients' diagnosis, prognosis, and treatment. In this review, we will cover all the current literature available for lncRNAs in melanoma and will discuss their potential benefits as diagnostic and/or prognostic markers or potent therapeutic targets in the treatment of melanoma patients.

LncRNA MSC-AS1, as an oncogene in melanoma, promotes the proliferation and glutaminolysis by regulating the miR-330-3p/YAP1 axis

Melanoma is a kind of aggressive skin neoplasms with high mortality. The purpose of this present research was to investigate the effects and potential mechanisms of long-noncoding RNA (lncRNA) MSC antisense RNA 1 (MSC-AS1) in melanoma. MSC-AS1, miR-330-3p and YAP1 expression levels in melanoma tissues and cells were assessed by quantitative real-time polymerase chain reaction. Melanoma cells were evaluated using cell count kit-8, clone formation and ELISA in vitro. The relationship among MSC-AS1, YAP1 and miR-330-3p was validated by pull-down and luciferase reporter assays. Finally, the role of MSC-AS1 in vivo was determined by the xenograft model. Results showed that lncRNA MSC-AS1 was upregulated in melanoma tissues and cells. High expression of MAS-AS1 was positively correlated with a poor prognosis. Pull-down and luciferase reporter demonstrated that miR-330-3p specifically binds directly to YAP1 and MSC-AS1, respectively. MSC-AS1 promoted the expression of YAP1 by downregulating miR-330-3p. Functional experiments suggested that knockdown of MSC-AS1 suppressed the proliferation of melanoma cells and decreased the levels of glutamine, glutamate and α-ketoglutarate, glutaminase and glutamine transporter alanine-serine-cysteine transporter 2. Upregulation of miR-330-3p alleviated the promotion effect of MSC-AS1 overexpression on the proliferation and glutaminolysis of melanoma cells. The above changes could be reversed by YAP1 overexpression. In addition, knockdown of MSC-AS1 dramatically restrained the growth of melanoma cells in xenograft model. In conclusion, our results revealed that MSC-AS1 facilitated the proliferation and glutaminolysis of melanoma cells by regulating miR-330-3p/YAP1 pathway, suggesting that MSC-AS1 could provide a new idea for the treatment of melanoma.

The role of lncRNA H19 in tumorigenesis and drug resistance of human Cancers

Systemic therapy is one of the most significant cancer treatments. However, drug resistance often appears and has become the primary cause of cancer therapy failure. Regulation of drug target, drug metabolism and drug efflux, cell death escape (apoptosis, autophagy, et al.), epigenetic changes, and many other variables are complicatedly involved in the mechanisms of drug resistance. In various types of cancers, long non-coding RNA H19 (lncRNA H19) has been shown to play critical roles in tumor development, proliferation, metastasis, and multiple drug resistance as well. The efficacy of chemotherapy, endocrine therapy, and targeted therapy are all influenced by the expression of H19, especially in breast cancer, liver cancer, lung cancer and colorectal cancer. Here, we summarize the relationship between lncRNA H19 and tumorigenesis, and illustrate the drug resistance mechanisms caused by lncRNA H19 as well. This review may provide more therapeutic potential targets for future cancer treatments.

LINC01061 triggers inflammation and inflammasome activation in autoimmune thyroiditis via microRNA-612/BRD4 axis

Considering the significance of LINC01061 in papillary thyroid cancer, here, we commenced to study the role of LINC01061 in autoimmune thyroid disease (AITD) and the potential mechanism. Thyroid tissues were attained from patients with AITD, and Nthy-ori 3-1 cells were induced with lipopolysaccharide (LPS), followed by measurement of LINC01061, microRNA (miR)-612, and BRD4 expression as well as their binding relation. The ectopic expression and silencing experimentations were carried out in LPS-induced Nthy-ori 3-1 cells to detect cell viability and apoptosis as well as inflammation and inflammasome. BRD4 and LINC01061 upregulation and miR-612 downregulation were observed in thyroid tissues of AITD patients and LPS-induced Nthy-ori 3-1 cells. Mechanistic analysis manifested that LINC01061 bound to miR-612 that negatively targeted BRD4. LINC01061 upregulated BRD4 to enhance cell viability, trigger inflammation and inflammasome activation but reduce apoptosis of LPS-induced Nthy-ori 3-1 cells by sponging miR-612. In conclusion, LINC01061 induced the occurrence of AITD by upregulation of miR-612-mediated BRD4 expression.

Novel lncRNA SNHG16 Promotes the Growth and Metastasis of Malignant Melanoma by Regulating miR-205-5p/PAK2 Axis

Background

Long non-coding RNAs (lncRNAs) play an key role in the biological processes of various malignant tumors. SNHG16 has been confirmed to be associated with the progression of various cancers. However, function and molecular mechanism of SNHG16 in melanoma have not been studied by scholars.

Methods

The expression of SNHG16 in melanoma tissues were detected by using qRT-PCR. Melanoma cases from The Cancer Genome Atlas (TCGA) and GEO#GSE15605 were included in this study. CCK-8 assay, EdU assay, transwell and scratch wound assay were used to explore the role of SNHG16 in melanoma cells. Luciferase reporter assays and RNA pull-down assay were used to explore the molecular mechanism of SNHG16 in melanoma.

Results

Here, we found that SNHG16 was up-regulated in melanoma. SNHG16 enhances the growth and metastasis of melanoma. SNHG16 can promote the expression of P21-activated kinases 2 (PAK2) by sponging miR-205-5p. PAK2 is the target gene of miR-205-5p. We demonstrated that SNHG16 promotes the metastasis and growth of melanoma through miR-205-5p/PAK2 axis.

Conclusion

This study firstly confirmed the role and mechanism of SNHG16 in the occurrence and development of melanoma. Therefore, SNHG16 may become a key point in the diagnosis, prognosis and treatment of melanoma patients in the future.

Investigating melanogenesis-related microRNAs as disease biomarkers in vitiligo

Vitiligo is considered a disabling disease that affects physical, social, psychological, and occupational aspects of an individual's quality of life. The search for non-invasive and reliable biomarkers for vitiligo's early diagnosis, prognosis, and treatment prediction is under intensive investigation. There is currently an emerging interest in employing miRNAs as biomarkers to predict vitiligo diagnosis and prognosis, inspired by the well-preserved nature of miRNAs in serum or plasma. In the current study, we assessed a panel of 20 melanogenesis pathway-related microRNAs (miRNAs) using quantitative real-time PCR technique in 85 non-segmental vitiligo (NSV) patients compared to 85 normal controls followed by function and pathway enrichment analysis for the miRNAs with significant results. Twelve out of the 20 circulating miRNAs showed significantly higher expression levels in vitiligo patients relative to controls where miR-423 show the highest expression level followed by miR-182, miR-106a, miR-23b, miR-9, miR-124, miR-130a, miR-203a, miR-181, miR-152, and miR-320a. While six miRNAs (miR-224, miR-148a, miR-137, and miR-7, miR-148b, miR-145, miR-374b, and miR-196b) didn’t show significant expression level. The analysis of the receiver operating curve indicated that miR-423, miR-106a, and miR-182 were outstanding biomarkers with the highest areas under the curve in vitiligo. This study is the first Egyptian study to investigate a panel of miRNAs expression profile in the plasma of patients with NSV. Our results suggest that specific circulating miRNAs signature might be implicated in vitiligo pathogenesis and could potentially be used as biomarkers in vitiligo.

Differential gene expression profile of multinodular goiter

Introduction

The goiter, a neglected heterogeneous molecular disease, remains a major indication for thyroidectomies in its endemic regions.

Objectives

This study analyzed differential gene expression in surgical specimens diagnosed with multi nodular and compared the data to that of thyroid tissue without multinodular goiter from patients undergoing thyroidectomy in Manaus-AM, Brazil using RNA-seq technology.

Methodology

The transcriptome information of the surgical specimen fragments with and without multinodular goiter was accessed by Illumina HiSeq 2000 New Generation Sequencing (NGS) using the RNA-seq NEBNext^® Ultra^™ RNA Library Prep Kit for Illumina^®—#E7530L protocol and differential gene expression analysis.

Results

Differences were found between the gene expression profiles of the diseased tissues and those of the healthy control tissues; at least 70 genes were differentially expressed. The HOTS gene was expressed only in multinodular goiter tissues (p < 0.05).

Conclusion

These results demonstrate that the gene expression profile of multinodular goiter is pro-tumoral and that HOTS can play a central role in multinodular goiter development.

Regulation of LncRNAs in Melanoma and Their Functional Roles in the Metastatic Process

Long non-coding RNAs (lncRNAs) are key regulators of numerous intracellular processes leading to tumorigenesis. They are frequently deregulated in cancer, functioning as oncogenes or tumor suppressors. As they act through multiple mechanisms, it is not surprising that they may exert dual functions in the same tumor. In melanoma, a highly invasive and metastatic tumor with the propensity to rapidly develop drug resistance, lncRNAs play different roles in: (i) guiding the phenotype switch and leading to metastasis formation; (ii) predicting the response of melanoma patients to immunotherapy; (iii) triggering adaptive responses to therapy and acquisition of drug resistance phenotypes. In this review we summarize the most recent findings on the lncRNAs involved in melanoma growth and spreading to distant sites, focusing on their role as biomarkers for disease diagnosis and patient prognosis, or targets for novel therapeutic approaches.

The pleiotropic roles of circular and long noncoding RNAs in cutaneous melanoma

Cutaneous melanoma (CM) is a very aggressive disease, often characterized by unresponsiveness to conventional therapies and high mortality rates worldwide. The identification of the activating BRAFV600 mutations in approximately 50% of CM patients has recently fueled the development of novel small-molecule inhibitors that specifically target BRAFV600 -mutant CM. In addition, a major progress in CM treatment has been made by monoclonal antibodies that regulate the immune checkpoint inhibitors. However, although target-based therapies and immunotherapeutic strategies have yielded promising results, CM treatment remains a major challenge. In the last decade, accumulating evidence points to the aberrant expression of different types of noncoding RNAs (ncRNAs) in CM. While studies on microRNAs have grown exponentially leading to significant insights on CM biology, the role of circular RNAs (circRNAs) and long noncoding RNAs (lncRNAs) in this tumor is less understood, and much remains to be discovered. Here, we summarize and critically review the available evidence on the molecular functions of circRNAs and lncRNAs in BRAFV600 -mutant CM and CM immunogenicity, providing recent updates on their functional role in targeted therapy and immunotherapy resistance. In addition, we also include an evaluation of several algorithms and databases for prediction and validation of circRNA and lncRNA functional interactions.

eIF4A3-induced circWAC promotes breast cancer progression through mediating miR-599/E2F3 axis

Circular RNAs (circRNAs) are implicated in the regulation of tumor progression via the "competitive endogenous RNAs (ceRNAs)" mechanism. We intended to explore the molecular mechanism of circRNA WW domain containing adaptor with coiled-coil (circWAC) in breast cancer (BC) progression. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Western blot assay were applied to analyze RNA and protein expression. Cell proliferation, migration, invasion, apoptosis, glycolysis, and tumorigenesis in nude mice were assessed to analyze the role of circWAC/microRNA-599 (miR-599)/E2F transcription factor 3 (E2F3) axis in BC. Dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay and RNA-pull down assay were performed to verify intermolecular interactions. CircWAC was up-regulated in BC tissues and cell lines. CircWAC knockdown restrained the proliferation, migration, invasion, and glycolysis and promoted the apoptosis of BC cells. CircWAC acted as miR-599 sponge, and miR-599 interference largely reversed circWAC silencing-induced effects in BC cells. MiR-599 interacted with the 3' untranslated region (3'UTR) of E2F3, and miR-599 overexpression-induced suppressive effect on cellular malignant potential was overturned by the accumulation of E2F3 in BC cells. Eukaryotic initiation factor 4A3 (eIF4A3) induced the expression of circWAC in BC cells. CircWAC knockdown suppressed xenograft tumor growth in vivo. Our results demonstrated that eIF4A3-induced circWAC promoted the proliferation, migration, invasion, and glycolysis and suppressed the apoptosis of BC cells through mediating miR-599/E2F3 axis, which provided novel potential targets for BC therapy.

MicroRNA-106a-5p promotes the proliferation, autophagy and migration of lung adenocarcinoma cells by targeting LKB1/AMPK

It has previously been reported that lung cancer has the highest morbidity and mortality rate worldwide; however, the pathogenesis underlying lung cancer has not been fully elucidated. The aim of the present was primarily to assess the influence of microRNA (miR)-106a-5p on the biological behaviors of lung cancer cells. In the present study, bioinformatics analysis was used to analyze the expression characteristics of miR-106a-5p and its relationship with the prognosis of patients with lung adenocarcinoma (LUAD) in The Cancer Genome Atlas. A dual luciferase reporter assay was performed to verify the binding of miR-106a-5p and liver kinase B1 (LKB1). The Cell Counting Kit-8, colony formation and Transwell assays were utilized to detect cell viability, proliferation and migration, respectively. Protein and RNA expression levels were examined by western blotting and reverse transcription-quantitative PCR analysis, respectively. It was observed that miR-106a-5p was highly expressed in LUAD and associated with poor prognosis. miR-106a-5p promoted the proliferation and migration of LUAD cells, and inhibited autophagy. By contrast, LKB1 inhibited cell proliferation and migration, promoted autophagy and blocked the cancer-promoting effects of miR-106a-5p. Overexpression of miR-106a-5p inhibited the phosphorylation of AMP-activated protein kinase (AMPK) and tuberin (TSC2), and promoted the phosphorylation of mTOR. By contrast, overexpression of LKB1 blocked the promotion of mTOR phosphorylation, and the inhibition of AMPK and TSC2 phosphorylation caused by miR-106a-5p. In summary, the results of the present study indicated that miR-106a-5p regulated the phosphorylation of the AMPK pathway by targeting LKB1, and was involved in the proliferation, migration and autophagy of LUAD cells.

Targeting long non coding RNA by natural products: Implications for cancer therapy

In spite of achieving substantial progress in its therapeutic strategies, cancer-associated prevalence and mortality are persistently rising globally. However, most malignant cancers either cannot be adequately diagnosed at the primary phase or resist against multiple treatments such as chemotherapy, surgery, radiotherapy as well as targeting therapy. In recent decades, overwhelming evidences have provided more convincing words on the undeniable roles of long non-coding RNAs (lncRNAs) in incidence and development of various cancer types. Recently, phytochemical and nutraceutical compounds have received a great deal of attention due to their inhibitory and stimulatory effects on oncogenic and tumor suppressor lncRNAs respectively that finally may lead to attenuate various processes of cancer cells such as growth, proliferation, metastasis and invasion. Therefore, application of phytochemicals with anticancer characteristics can be considered as an innovative approach for treating cancer and increasing the sensitivity of cancer cells to standard prevailing therapies. The purpose of this review was to investigate the effect of various phytochemicals on regulation of lncRNAs in different human cancer and evaluate their capabilities for cancer treatment and prevention.

Molecular characterization of metabolic subtypes of gastric cancer based on metabolism-related lncRNA

Increasing evidence has demonstrated that lncRNAs are critical regulators in diverse biological processes, but the function of lncRNA in metabolic regulation remains largely unexplored. In this study, we evaluated the association between lncRNA and metabolic pathways and identified metabolism-related lncRNAs. Gastric cancer can be mainly subdivided into 2 clusters based on these metabolism-related lncRNA regulators. Comparative analysis shows that these subtypes are found to be highly consistent with previously identified subtypes based on other omics data. Functional enrichment analysis shows that they are enriched in distinct biological processes. Mutation analysis shows that ABCA13 is a protective factor in subtype C1 but a risk factor in C2. Analysis of chemotherapeutic and immunotherapeutic sensitivity shows that these subtypes tend to display distinct sensitivity to the same chemical drugs. In conclusion, these findings demonstrated the significance of lncRNA in metabolic regulation. These metabolism-related lncRNA regulators can improve our understanding of the underlying mechanism of lncRNAs and advance the research of immunotherapies in the clinical management of gastric cancer.

The Functional Role of Long Non-Coding RNAs in Melanoma

Melanoma is the most lethal skin cancer, with increasing incidence worldwide. The molecular events that drive melanoma development and progression have been extensively studied, resulting in significant improvements in diagnostics and therapeutic approaches. However, a high drug resistance to targeted therapies and adverse effects of immunotherapies are still a major challenge in melanoma treatment. Therefore, the elucidation of molecular mechanisms of melanomagenesis and cancer response to treatment is of great importance. Recently, many studies have revealed the close association of long noncoding RNAs (lncRNAs) with the development of many cancers, including melanoma. These RNA molecules are able to regulate a plethora of crucial cellular processes including proliferation, differentiation, migration, invasion and apoptosis through diverse mechanisms, and even slight dysregulation of their expression may lead to tumorigenesis. lncRNAs are able to bind to protein complexes, DNA and RNAs, affecting their stability, activity, and localization. They can also regulate gene expression in the nucleus. Several functions of lncRNAs are context-dependent. This review summarizes current knowledge regarding the involvement of lncRNAs in melanoma. Their possible role as prognostic markers of melanoma response to treatment and in resistance to therapy is also discussed.

Pathogenic roles of long noncoding RNAs in melanoma: Implications in diagnosis and therapies

Melanoma is one of the most dangerous types of cutaneous neoplasms, which are pigment-producing cells of neuroectodermal origin found all over the body. A great deal of research is focused on the mechanisms of melanoma to promote better diagnostic and treatment options for melanoma in its advanced stages. The progression of melanoma involves alteration in different levels of gene expression. With the successful implementation of next-generation sequencing technology, an increasing number of long noncoding RNAs (lncRNAs) sequences have been discovered, and a significant number of them have phenotypic effects in both in vitro and in vivo studies, implying that they play an important role in the occurrence and progression of human cancers, particularly melanoma. A number of evidence indicated that lncRNAs are important regulators in tumor cell proliferation, invasion, apoptosis, immune escape, energy metabolism, drug resistance, epigenetic regulation. To better understand the role of lncRNAs in melanoma tumorigenesis, we categorize melanoma-associated lncRNAs according to their cellular functions and associations with gene expression and signaling pathways in this review. Based on the mechanisms of lncRNA, we discuss the possibility of lncRNA-target treatments, and the application of liquid biopsies to detect lncRNAs in melanoma diagnosis and prognosis.

LncRNA H19: A novel oncogene in multiple cancers

Long non-coding RNAs (lncRNAs) are a series of non-coding RNAs that lack open reading frameworks. Accumulating evidence suggests important roles for lncRNAs in various diseases, including cancers. Recently, lncRNA H19 (H19) became a research focus due to its ectopic expression in human malignant tumors, where it functioned as an oncogene. Subsequently, H19 was confirmed to be involved in tumorigenesis and malignant progression in many tumors and had been implicated in promoting cell growth, invasion, migration, epithelial-mesenchymal transition, metastasis, and apoptosis. H19 also sequesters some microRNAs, facilitating a multilayer molecular regulatory mechanism. In this review, we summarize the abnormal overexpression of H19 in human cancers, which suggests wide prospects for further research into the diagnosis and treatment of cancers.

Role of Long Non-Coding RNAs in Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a debilitating condition of the pulmonary circulatory system that occurs in patients of all ages and if untreated, eventually leads to right heart failure and death. Despite existing medical treatment options that improve survival and quality of life, the disease remains incurable. Thus, there is an urgent need to develop novel therapies to treat this disease. Emerging evidence suggests that long non-coding RNAs (lncRNAs) play critical roles in pulmonary vascular remodeling and PAH. LncRNAs are implicated in pulmonary arterial endothelial dysfunction by modulating endothelial cell proliferation, angiogenesis, endothelial mesenchymal transition, and metabolism. LncRNAs are also involved in inducing different pulmonary arterial vascular smooth muscle cell phenotypes, such as cell proliferation, apoptosis, migration, regulation of the phenotypic switching, and cell cycle. LncRNAs are essential regulators of gene expression that affect various diseases at the chromatin, transcriptional, post-translational, and even post-translational levels. Here, we focus on the role of LncRNAs and their molecular mechanisms in the pathogenesis of PAH. We also discuss the current research challenge and potential biomarker and therapeutic potentials of lncRNAs in PAH.

Suppression of miR-106a-5p expression inhibits tumorigenesis via increasing CELF-2 expression in spinal cord glioma

Spinal cord glioma is a tumor characterized by high recurrence and mortality rates, and its treatment remains a major challenge. It has been reported that abnormal expression of microRNAs (miRNAs/miRs) is associated with tumor progression. Therefore, the current study aimed to identify novel miRNAs associated with spinal cord glioma. Herein, the expression levels of several miRNAs were determined in human spinal cord glioma and adjacent non-cancerous tissues by reverse transcription-quantitative (RT-qPCR). The results revealed that miR-106a-5p expression was markedly upregulated in spinal cord glioma tissues compared with in non-cancerous tissues. Furthermore, the biological effects of miR-106a-5p on spinal cord glioma cells were evaluated by MTT, Transwell and flow cytometric assays. In 0231SCG cells transfected with miR-106a-5p inhibitor, cell proliferation, migration and invasion were attenuated, whereas apoptosis was enhanced. A search of the TargetScan database revealed that miR-106a-5p directly targeted CUGBP Elav-like family member 2 (CELF-2). Western blot and RT-qPCR experiments further confirmed the association between miR-106a-5p and CELF-2 expression in spinal cord glioma tissues. The current results demonstrated that CELF-2 was a direct target of miR-106a-5p, and that the expression levels of CELF-2 were negatively associated with those of miR-106a-5p. In addition, overexpression of CELF-2 in spinal cord glioma cells reversed the tumor-promoting effects of miR-106a-5p both in vitro and in vivo. Overall, the aforementioned findings indicated that miR-106a-5p, which was highly expressed in spinal cord glioma tissues, may affect the proliferation, migration, invasion and apoptosis of spinal cord glioma cells via targeting CELF-2, thus indicating a potential approach to the future clinical management of spinal cord glioma.

Exosomal miR-106b-5p derived from melanoma cell promotes primary melanocytes epithelial-mesenchymal transition through targeting EphA4

Background

Cancer-secreted exosomal miRNAs regulates the biological processes of many tumours. The serum level of exosomal miR-106b-5p is significantly increased in melanoma patients. However, the role and molecular mechanisms of exosomal miR-106b-5p in melanoma remains unclear.

Methods

Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of miR-106b-5p and EphA4 in melanoma tissues. Transmission electron microscopy (TEM) and western blotting were used to identify exosome. QRT-qPCR and Cy3-labelled miR-106b-5p were used to demonstrated the transmission of melanoma cell-secreted exosomal miR-106b-5p. Western blotting, Immunofluorescence, adhesion, transwell and scratch wound assay were used to explore the role of exosomal miR-106b-5p in melanocytes. Luciferase reporter assays and RNA-Chromatin Immunoprecipitation (ChIP) assay were used to confirm whether erythropoietin-producing hepatocellular carcinoma receptor A4 (EphA4) was a direct target of miR-106b-5p.

Results

We found that miR-106b-5p levels were increased in melanoma tissue, and high miR-106b-5p expression is an independent risk factor for the overall survival of patients with melanoma. miR-106b-5p is enriched in melanoma cell-secreted exosomes and transferred to melanocytes. Exosomal miR-106b-5p promotes the epithelial-to-mesenchymal transition (EMT), migration, invasion and adhesion of melanocytes. Exosomal miR-106b-5p exerted its role by targeting EphA4 to activate the ERK pathway. We demonstrated that exosomal miR-106b-5p promoted melanoma metastasis in vivo through pulmonary metastasis assay.

Conclusions

Thus, melanoma cell-secreted exosomal miR-106b-5p may serve as a diagnostic indicator and potential therapeutic target in melanoma patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-01906-w.

Downregulation of lncRNA H19 sensitizes melanoma cells to cisplatin by regulating the miR-18b/IGF1 axis

Long noncoding RNAs (LncRNAs) lncRNA H19 has been shown to be involved in the chemotherapy resistance of cancer cells. However, the role of lncRNA H19 in chemotherapy resistance of melanoma cells remains unknown. Here, we determined lncRNA H19, miR-18b, and insulin-like growth factor 1 (IGF1) expression by utilizing quantitative real-time PCR. Cell proliferation ability and chemosensitivity were assessed by colony formation assay and MTT assay. Flow cytometry assay was applied to detect cell apoptosis. We discovered that lncRNA H19 was upregulated, but miR-18b was downregulated in melanoma tissues and cisplatin (DDP)-resistant melanoma cells. The overall survival for the group with lower lncRNA H19 was significantly better than the group with higher H19. IGF1 mRNA level was higher in melanoma tissues than that in normal tissues. miR-18b expression level A negative correlation was observed between the expression levels of miR-18b, lncRNA H19, and IGF1 mRNA. Functionally, knockdown of lncRNA H19 sensitized resistant A375/DDP and M8/DDP cells to DDP. Silencing lncRNA H19 inhibited colony formation ability and promoted apoptosis of DDP-resistant melanoma cells, which was abrogated by miR-18b inhibition and IGF1 upregulation. Mechanistically, lncRNA H19 directly interacted with miR-18b to regulate its expression. IGF1 was identified as a target of miR-18b. These findings highlight the fact that lncRNA H19 could influence DDP-resistance by modulating the miR-18b/IGF axis in melanoma cells, suggesting a new potential therapeutic target for melanoma patient treatment.

H19/miR-107/HMGB1 axis sensitizes laryngeal squamous cell carcinoma to cisplatin by suppressing autophagy in vitro and in vivo

Laryngeal squamous cell carcinoma (LSCC) is the most common malignant tumor, which occurs in the head and neck. Current treatments for LSCC are all largely weakened by increasing drug resistance. Our study aimed to investigate the effects of long noncoding RNA (lncRNA) H19 on drug resistance in LSCC. In our study, we found that the level of H19 was sharply upregulated in LSCC tissues and drug-resistant cells compared with the control. Besides, the expression of high-mobility group B1 (HMGB1) was elevated, and microRNA107 (miR-107) was suppressed in drug-resistant cells compared with the control. Further study revealed that the interference of H19 by short hairpin RNA (shRNA) effectively suppressed high autophagy level and obvious drug resistance in drug-resistant cells. Besides that, miR-107 was predicted as a target of H19 and inhibiting effects of H19 shRNA on autophagy and drug resistance were both reversed by miR-107 inhibitor. Moreover, HMGB1 was predicted as a target of miR-107 in LSCC cells and knockdown of HMGB1 was able to suppress autophagy and drug resistance in LSCC cells. In addition, our investigation demonstrated that H19 shRNA exerted an inhibiting effect on autophagy and drug resistance by downregulating HMGB1 by targeting miR-107. Finally, the in vivo experiment revealed that LV-H19 shRNA strongly suppressed drug resistance compared with the usage of cisplatin individually. Taken together, our research indicated an H19-miR-107-HMGB1 axis in regulating the autophagy-induced drug resistance in LSCC in vitro and in vivo, providing novel targets for molecular-targeted therapy and broadening the research for LSCC.

Involvement of Long Non-Coding RNAs in Glucose Metabolism in Cancer

The rapid and uncontrolled proliferation of cancer cells is supported by metabolic reprogramming. Altered glucose metabolism supports cancer growth and progression. Compared with normal cells, cancer cells show increased glucose uptake, aerobic glycolysis and lactate production. Byproducts of adjusted glucose metabolism provide additional benefits supporting hallmark capabilities of cancer cells. Long non-coding RNAs (lncRNAs) are a heterogeneous group of transcripts of more than 200 nucleotides in length. They regulate numerous cellular processes, primarily through physical interaction with other molecules. Dysregulated lncRNAs are involved in all hallmarks of cancer including metabolic alterations. They may upregulate metabolic enzymes, modulate the expression of oncogenic or tumor-suppressive genes and disturb metabolic signaling pathways favoring cancer progression. Thus, lncRNAs are not only potential clinical biomarkers for cancer diagnostics and prediction but also possible therapeutic targets. This review summarizes the lncRNAs involved in cancer glucose metabolism and highlights their underlying molecular mechanisms.

Elevated LINC01550 induces the apoptosis and cell cycle arrest of melanoma

Melanoma is a high-grade malignant subtype of human skin cancer with the highest mortality rate. Here we perform a bioinformatics analysis concerning human melanoma tissues by the Gene Expression Omnibus (GEO) database and Gene Expression Profiling Interactive Analysis (GEPIA) platform. We found that lncRNA LINC01550 was significantly down-regulated in the melanoma tissues as compared to the normal tissues. The low expression of LINC01550 was tightly associated with shorter overall survival and disease-free survival of patients with melanoma. LINC01550 expression is negatively associated with tumor cell proliferation and invasion abilities in melanoma as evidenced by the single-cell RNA sequencing (scRNA-seq) databases. LINC01550-overexpressing vectors were transferred into melanoma cells (WM35 and WM451). Up-regulation of LINC01550 significantly inhibited proliferation and invasion abilities, as well as induced cell apoptosis and G1 and S phase arrest of the melanoma cells. In conclusion, overexpression of LINC01550 may serve as a potential therapeutic target for melanoma.

Comprehensive Review on the Clinical Relevance of Long Non-Coding RNAs in Cutaneous Melanoma

Cutaneous melanoma is considered a rare tumor, although it is one of the most common cancers in young adults and its incidence has risen in the last decades. Targeted therapy, with BRAF and MEK inhibitors, and immunotherapy revolutionized the treatment of metastatic melanoma but there is still a considerable percentage of patients with primary or acquired resistance to these therapies. Recently, oncology researchers directed their attention at the role of long non-coding RNAs (lncRNAs) in different types of cancers, including melanoma. lncRNAs are RNA transcripts, initially considered "junk sequences", that have been proven to have a crucial role in the fine regulation of physiological and pathological processes of different tissues. Furthermore, they are more expressed in tumors than protein-coding genes, constituting perfect candidates either as biomarkers (diagnostic, prognostic, predictive) or as therapeutic targets. In this work, we reviewed all the literature available for lncRNA in melanoma, elucidating all the potential roles in this tumor.

The double-edged sword of H19 lncRNA: Insights into cancer therapy

H19 long non-coding RNA (lncRNA) has many functions in cancer. Some studies have reported that H19 acts as an oncogene and is involved in cancer progression by activating epithelial-mesenchymal transition (EMT), the cell cycle and angiogenesis via mechanisms like microRNA (miRNA) sponging - the binding to and inhibition of miRNA activity. This makes H19 lncRNA a potential target for cancer therapeutics. However, several conflicting studies have also found that H19 suppresses tumour development. In this review, we shed light on the possible reasons for these conflicting findings. We also summarise the current literature on the applications of H19 lncRNA in cancer therapy in many cancers and explore new avenues for future research. This includes the use of H19 in recombinant vectors, chemoresistance, epigenetic regulation, tumour microenvironment alteration and cancer immunotherapy. The relationship between H19 and the master tumour suppressor gene p53 is also explored. In most studies, H19 knockdown via RNA interference (RNAi) or epigenetic silencing inhibits cancer development. Thus, H19 lncRNA could be a promising target for the development of cancer therapeutics. This warrants further investigations into its translational research to improve cancer therapy outcomes.

Long non-coding RNA XIST binding to let-7c-5p contributes to rheumatoid arthritis through its effects on proliferation and differentiation of osteoblasts via regulation of STAT3

BACKGROUND

Rheumatoid arthritis (RA), a chronic autoimmune disease, affects around 1% population worldwide, with the life quality of patients severely reduced. In this study, it is intended to explore the role of long non-coding RNA X-inactive specific transcript (lncRNA XIST) in RA and the underlying mechanisms associated with let-7c-5p and signal transducer and activator of transcription 3 (STAT3).

METHODS

LncRNA XIST, let-7c-5p, and STAT3 expressions were determined in RA and normal cartilage tissues, and their relationship was analyzed in osteoblasts. The regulatory effects of lncRNA XIST in RA were investigated when XIST expression was upregulated or downregulated in osteoblasts. TNF-α, IL-2, IL-6, alkaline phosphatase (ALP), osteocalcin, TGF-β1, and IGF1 were measured in vivo in RA rats.

RESULTS

LncRNA XIST and STAT3 were expressed at high levels and let-7c-5p expressed at a low level in RA cartilage tissues. LncRNA XIST silencing or let-7c-5p enhancement led to decreased levels of TNF-α, IL-2, and IL-6, suggestive of suppressed inflammatory response, and increased levels of ALP, osteocalcin, TGF-β1, and IGF-1 as well as reduced damage in cartilage tissues.

CONCLUSION

LncRNA XIST downregulation could promote proliferation and differentiation of osteoblasts in RA, serving as a future therapeutic target for RA.

The Role of Long Non-coding RNAs in Cancer Metabolism: A Concise Review

Dysregulation of metabolic pathways in cancer cells is regarded as a hallmark of cancer. Identification of these abnormalities in cancer cells dates back to more than six decades, far before discovery of oncogenes and tumor suppressor genes. Based on the importance of these pathways, several researchers have aimed at modulation of these functions to intervene with the pathogenic course of cancer. Numerous genes have been shown to participate in the regulation of metabolic pathways, thus aberrant expression of these genes can be involved in the pathogenesis of cancer. The recent decade has experienced a significant attention toward the role of long non-coding RNAs (lncRNAs) in the biological functions. These transcripts regulate expression of genes at several levels, therefore influencing the activity of cancer-related pathways. Among the most affected pathways are those modulating glucose homeostasis, as well as amino acid and lipid metabolism. Moreover, critical roles of lncRNAs in regulation of mitochondrial function potentiate these transcripts as novel targets for cancer treatment. In the current review, we summarize the most recent literature regarding the role of lncRNAs in the cancer metabolism and their significance in the design of therapeutic modalities.

LncRNAH19 improves insulin resistance in skeletal muscle by regulating heterogeneous nuclear ribonucleoprotein A1

Background

Skeletal muscle is essential for glucose and lipid metabolism. Growing evidence reveals the importance of long non-coding RNAs (LncRNAs) in metabolism. This study aimed to investigate the function of LncRNA H19 (H19) in lipid metabolism of skeletal muscle and its potential mechanisms.

Methods

Glucose tolerance, serum insulin and lipid content in serum and skeletal muscle were determined in control and H19-overexpressed db/db mice. Lipid metabolism was evaluated in H19-overexpressed or H19-silencing muscle cells by detecting lipid contents and mitochondria related functions. The underlying mechanisms were explored by RNA pull-down, mass spectrometry and RNA immunoprecipitation (RIP).

Results

H19 was downregulated in skeletal muscle of db/db mice. H19 overexpression in db/db mice inhibited lipid ectopic deposition in skeletal muscle, meanwhile improved glucose intolerance and insulin resistance as compared with control db/db mice treated with ad-GFP. Furthermore, overexpression of H19 reversed FFA-induced lipid accumulation and increased cellular respiration in muscle cells, while H19 knockdown exhibited opposite effects in muscle cells. Mechanistically, H19 interacted with heterogeneous nuclear ribonucleoprotein (hnRNPA1) which was validated by RNA pulldown and RIP analysis, which increased translation of fatty acid oxidation closely related genes PGC1a and CPT1b.

Conclusion

Our data suggest that overexpression of H19 ameliorates insulin resistance by reducing ectopic lipid accumulation in skeletal muscle. The possible underlying mechanisms are that overexpression of lncRNAH19 promotes fatty acids oxidation via targeting of hnRNPA1.

The critical roles of lncRNAs in the pathogenesis of melanoma

Long non-coding RNAs (lncRNAs) embrace a huge fraction of human transcripts and participate in the pathogenesis of human disorders especially malignant conditions. Malignant melanoma, as the most fatal type of cutaneous malignnacies, is associated with dysregulation of several lncRNAs including PVT1, H19, MALAT1, and CCAT1. Moreover, a portion of lncRNAs are exclusively expressed in melanoma cell lines. Expression levels of several lncRNAs are associated with TNM stage, tumor size and progression of melanoma. Thus, these lncRNAs are regarded as biomarkers for this malignancy. Peripheral transcript levels of a number of lncRNAs, such as PVT1, SNHG5 and SPRY4-IT1, could distinguish melanoma patients from unaffected persons with appropriate sensitivity and specificity values. Moreover, expression levels of numerous lncRNAs in tissue biopsies could differentiate malignant samples from benign samples. Based on the results of both cell line and in vivo studies, lncRNAs regulate critical pathways in the carcinogenesis of melanoma, such as the PI3K/Akt and NF-κB signaling pathways, and are involved in the modulation of response to chemotherapeutic agents. Here we review the existing information on the role of lncRNAs in malignant melanoma.

Long noncoding RNA Linc00337 functions as an E2F1 co-activator and promotes cell proliferation in pancreatic ductal adenocarcinoma

BACKGROUND

Long noncoding RNA (lncRNA) Linc00337 has been implicated in lung, gastric, colorectal and esophageal squamous cell carcinoma progression via various mechanisms; however, its clinicopathological significance and role in pancreatic ductal adenocarcinoma (PDAC) progression remains largely unknown.

METHODS

Multiple approaches such as bioinformatic analysis, Transfection, quantitative real-time-PCR, Western blotting, animal studies, RNA-immunoprecipitation (RIP), RNA-pulldown and RNA-Fluorescence in situ hybridization (RNA-FISH) and were utilized to explore the role of Linc00337 in PDAC.

RESULTS

Here we identified Linc00337 is an oncogenic lncRNA during PDAC progression. We found that the expression of Linc00337 is elevated in PDAC tissues and the higher Linc00337 predicts dismal prognosis. Functionally, Linc00337 promotes PDAC cell proliferation and cell cycle transition both in vitro and in vivo. Mechanistically, Linc00337 binds to E2F1 and functions as an E2F1 coactivator to trigger the targets expression during PDAC progression.

CONCLUSION

Our results demonstrate a reciprocal regulation mechanism between Linc00337 and E2F1 in PDAC progression and report the clinical value of Linc00337 for PDAC prognosis and treatment.

Knockdown of lincRNA PADNA promotes bupivacaine-induced neurotoxicity by miR-194/FBXW7 axis

BACKGROUND

The aim of the study was to explore the function and mechanism of lincRNA PADNA in bupivacaine-induced neurotoxicity.

METHODS

Mouse DRG neurons were cultured in vitro and treated with bupivacaine to establish a neurotoxicity model. Caspase3 activity, cell viability, and TUNEL assays were analyzed to assess the role of lincRNA PADNA. A dual-luciferase reporter assay was used to determine the binding target of lincRNA PANDA.

RESULTS

The expression of lincRNA PADNA was significantly increased with increasing concentrations of bupivacaine. Functional analysis revealed that knockdown of lincRNA PADNA increased caspase3 activity and inhibited cell viability. Western blot analysis showed that knockdown of lincRNA PADNA promoted cleaved caspase3 levels. We also revealed that lincRNA PADNA may bind with miR-194. Knockdown of miR-194 rescued the function of lincRNA PADNA, suggesting that lincRNA PADNA may sponge miR-194. In addition, we provided new evidence that the lincRNA PADNA/miR-194/FBXW7 axis plays an important role in the neurotoxicity process.

CONCLUSION

We performed comprehensive experiments to verify the function and mechanism of lincRNA PADNA in bupivacaine-induced neurotoxicity. Our study provides new evidence and clues for the prevention of neurotoxicity.

A novel LncRNA transcript, RBAT1, accelerates tumorigenesis through interacting with HNRNPL and cis-activating E2F3

BACKGROUND

Long non-coding RNAs (lncRNAs) have been identified as important epigenetic regulators that play critical roles in human cancers. However, the regulatory functions of lncRNAs in tumorigenesis remains to be elucidated. Here, we aimed to investigate the molecular mechanisms and potential clinical application of a novel lncRNA, retinoblastoma associated transcript-1 (RBAT1), in tumorigenesis.

METHODS

RBAT1 expression was determined by real-time PCR in both retinoblastoma (Rb) and bladder cancer (BCa) cell lines and clinical tissues. Chromatin isolation using RNA purification (ChIRP) assays were performed to identify RBAT1-interacting proteins. Patient-derived xenograft (PDX) retinoblastoma models were established to test the therapeutic potential of RBAT1-targeting GapmeRs.

RESULTS

Here, we found that RBAT1 expression was significantly higher in Rb and BCa tissues than that in adjacent tissues. Functional assays revealed that RBAT1 accelerated tumorigenesis both in vitro and in vivo. Mechanistically, RBAT1 recruited HNRNPL protein to E2F3 promoter, thereby activating E2F3 transcription. Therapeutically, GapmeR-mediated RBAT1 silencing significantly inhibited tumorigenesis in orthotopic xenograft retinoblastoma models derived from Rb cell lines and Rb primary cells.

CONCLUSIONS

RBAT1 overexpression upregulates a known oncogene, E2F3, via directly recruiting HNPNPL to its promoter and cis-activating its expression. Our finding provides a novel mechanism of lncRNA biology and provides potential targets for diagnosis and treatment of Rb and BCa.

RETRACTED: Long non-coding RNA LINC00160 functions as a decoy of microRNA-132 to mediate autophagy and drug resistance in hepatocellular carcinoma via inhibition of PIK3R3

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the authors. Following the publication of the above article, the authors found that “LINC00160 did not affect Atg5 and P65 protein expression in HCC cells, which was inconsistent with the result of this paper. Furthermore, we apologize to the readership of the Journal for any inconvenience caused.” Additionally, after publication, the journal was made aware of comments in relation to this article (https://pubpeer.com/publications/333AE65483683ADF50A723BE34AD62). The authors have not responded to our request to respond to these comments.

LINC00619 restricts gastric cancer progression by preventing microRNA-224-5p-mediated inhibition of OPCML

Several long intergenic noncoding RNAs (lincRNAs) have been linked to carcinogenesis; however, little is known about the role of LINC00619 in gastric cancer (GC). LINC00619 was identified among differentially expressed lncRNAs linked to gastric cancer based on microarray analysis and its relationships with miR-224-5p and opioid binding protein/cell adhesion molecule-like gene (OPCML) were investigated. LINC00619, miR-224-5p, and OPCML expression were measured in GC tissues and cells. Ectopic expression and depletion experiments were conducted to assess the effects of LINC00619, miR-224-5p and OPCML on cell proliferation, invasion, migration and apoptosis as well as their effects on the expression of apoptosis- and metastasis-related genes (Bcl-2, Bax, MMP-2 and MMP-9). Tumorigenicity in the nude mice was also examined. Gastric cancer was characterized by downregulation of LINC00619 and OPCML and upregulation of miR-224-5p. Additionally, we found that miR-224-5p could interact with both LINC00619 and OPCML. Upregulation of LINC00619, which binds to miR-224-5p, led to decreased miR-224-5p expression while increasing the expression of OPCML, a target gene of miR-224-5p. Overexpression of LINC00619 or OPCML or downregulation of miR-224-5p suppressed cell proliferation, invasion, migration and tumorigenicity while promoting apoptosis in GC. Our results indicated that LINC00619 functions as a tumor suppressor in GC by impairing miR-224-5p-mediated inhibition of OPCML.

Long Intervening Noncoding 00467 RNA Contributes to Tumorigenesis by Acting as a Competing Endogenous RNA against miR-107 in Cervical Cancer Cells

The functional roles of individual large intervening noncoding RNAs in carcinogenesis and progression of cervical cancer have been uncovered in previous studies. In this study, we aimed to identify the role of long intervening noncoding 00467 (LINC00467) in epithelial-mesenchymal transition (EMT), invasion and migration of cervical cancer cells by regulating miR-107 and kinesin family member 23 (KIF23). Microarray analyses were used to detect cervical cancer-related differentially expressed genes, followed by determination of LINC00467, miR-107, and KIF23 levels and subcellular location of LINC00467. Cervical cancer cells were treated with a series of siRNA and mimics to measure the regulatory role of LINC00467, miR-107, and KIF23 in EMT, cell invasion, migration and proliferation, and tumorigenic ability in vivo and in vitro. LINC00467 and KIF23 were highly expressed, whereas miR-107 was poorly expressed, in cervical cancer. LINC00467 was found to be primarily located in the cytoplasm and function as a competing endogenous RNA against miR-107 to suppress KIF23. Cell proliferation, migration, invasion, and EMT in vitro were inhibited as a result of lentiviral-mediated LINC00467 knockdown and miR-107 overexpression in cervical cancer. In addition, LINC00467 silencing or miR-107 up-regulation repressed tumorigenic ability in xenograft tumor-bearing nude mice in cervical cancer in vivo. LINC00467 silencing or miR-107 up-regulation may serve as novel potential strategies for the treatment of cervical cancer.

LncRNAs regulate metabolism in cancer

Metabolic reprogramming is a hallmark of cancer. Mammalian genome is characterized by pervasive transcription, generating abundant non-coding RNAs (ncRNAs). Long non-coding RNAs (lncRNAs) are freshly discovered functional ncRNAs exerting extensive regulatory impact through diverse mechanisms. Emerging studies have revealed widespread roles of lncRNAs in the regulation of various cellular activities, including metabolic pathways. In this review, we summarize the latest advances regarding the regulatory roles of lncRNAs in cancer metabolism, particularly their roles in mitochondrial function, glucose, glutamine, and lipid metabolism. Moreover, we discuss the clinical application and challenges of targeting lncRNAs in cancer metabolism. Understanding the complex and special behavior of lncRNAs will allow a better depiction of cancer metabolic networks and permit the development of lncRNA-based clinical therapies by targeting cancer metabolism.

Upregulation of lncRNA H19 promotes nasopharyngeal carcinoma proliferation and metastasis in let-7 dependent manner

The aim of this study is to analyse the expression status of long non-coding RNA (lncRNA) H19 in nasopharyngeal carcinoma and to unravel its oncogenic properties at molecular level. The abundance of H19, let-7a, b, g, i and HRAS was quantified by real-time PCR. Cell viability was measured by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method. Cell proliferation was evaluated by the cell counting. Cell migration and cell invasion were determined using transwell chamber and scattering colony formation. Tumour progression was monitored in xenograft tumour model and tail vein injection was adopted for lung metastasis assessment. Luciferase reporter assay was employed to interrogate the potential regulatory action of let-7 genes on H19 expression. The endogenous HRAS protein was quantified by western blotting. H19 was aberrantly over-expression in nasopharyngeal carcinoma, which intimately associated with poorer prognosis. H19-deficency significantly inhibited cell viability and suppressed cell proliferation. Furthermore, both migrative and invasive capacity were compromised by H19 knockdown. H19-silencing remarkably delayed xenograft tumour progression and lung metastasis. Mechanistically, H19 competitively sponged let-7 genes and therefore up-regulated HRAS, which consequently contributed to its oncogenic activity in nasopharyngeal carcinomas. Our study uncovered the oncogenic properties of H19 in nasopharyngeal carcinoma and highlighted the H19-let-7-HRAS signalling axis underlying the incidence and metastasis of this disease.

The genetic script of metastasis

Metastasis is a pivotal event that changes the course of cancers from benign and treatable to malignant and difficult to treat, resulting in the demise of patients. Understanding the genetic control of metastasis is thus crucial to develop efficient and sustainable targeted therapies. Here we discuss the alterations in epigenetic mechanisms, transcription, chromosomal instability, chromosome imprinting, non-coding RNAs, coding RNAs, mutant RNAs, enhancers, G-quadruplexes, and copy number variation to dissect the genetic control of metastasis. We conclude that the genetic control of metastasis is predominantly executed through epithelial to mesenchymal transition and evasion of cell death. We discuss how genetic regulatory mechanisms can be harnessed for therapeutic purposes to achieve sustainable control over cancer metastasis.

The Identification of Long Non-coding RNA H19 Target and Its Function in Chronic Myeloid Leukemia

H19 is a long non-coding RNA which was lowly expressed in chronic myeloid leukemia (CML). Here, we found that the overexpression of H19 significantly inhibited cell viability and colony formation and prolongs survival in CML cell lines and three xenografted mouse models. The H19 target proteins and microRNAs (miRNAs) were identified using a combination of computational prediction and RNA pull-down, including PCBP1, FUS protein, and miR-19a-3p and miR-106b-5p. Targeting PCBP1, FUS protein, miR-19a-3p, and miR-106b-5p significantly inhibits the cell growth and colony formation of CML cell lines. Co-overexpression of H19 and PCBP1, FUS, miR-19a-3p, and miR-106b-5p decreases the inhibitory effect of H19 in CML. These findings might provide a novel molecular insight into CML.

Regulation of Glucose and Lipid Metabolism by Long Non-coding RNAs: Facts and Research Progress

Long non-coding RNAs (lncRNAs) are a type of non-coding RNA with a length that exceeds 200 nucleotides. Previous studies have shown that lncRNAs play an important role in the pathogenesis of various diseases. Research in both animal models and humans has begun to unravel the profound complexity of lncRNAs and demonstrated that lncRNAs exert direct effects on glucose and lipid metabolism both in vivo and in vitro. Such research has elucidated the regulatory role of lncRNAs in glucose and lipid metabolism in human disease. lncRNAs mediate glucose and lipid metabolism under physiological and pathological conditions and contribute to various metabolism disorders. This review provides an update on our understanding of the regulatory role of lncRNAs in glucose and lipid metabolism in various diseases. As our understanding of the function of lncRNAs improves, the future is promising for the development of new diagnostic biomarkers that utilize lncRNAs and treatments that target lncRNAs to improve clinical outcomes.