LncRNA LINC00240 suppresses invasion and migration in non-small cell lung cancer by sponging miR-7-5p

The role of mir-7-5p in cancer: function, prognosis, diagnosis, and therapeutic implications

One of the important and conserved microRNAs (miRNAs), miR-7-5p, is involved in several pathological mechanisms, including cell proliferation, apoptosis, migration, and metastasis. Dysregulation of this miRNA's expression is correlated with multiple diseases, especially cancer. Its role as a tumor suppressor has been demonstrated in various types of cancer, such as colorectal cancer, lung cancer, bladder cancer, breast cancer, and glioblastoma. Furthermore, several studies have highlighted the prognostic and diagnostic value of this miRNA, which could be valuable for the diagnosis and treatment of certain disorders. We present an overview of the latest findings regarding miR-7-5p's role in the development of cancer, its action mechanisms, and expression, based on in vivo, in vitro, and human research. Additionally, we discuss the function of miR-7-5p as a prognostic biomarker in cancer and explore its potential as a therapeutic target.

Precision Nanomedicine: Lapatinib-Loaded Chitosan-Gold Nanoparticles Targeting LINC01615 for Lung Cancer Therapy

Long non-coding RNAs (lncRNAs) play essential roles as oncogenic factors in cancer progression by influencing cell proliferation, apoptosis, and metastasis pathways. This study aims to investigate the expression changes of LINC01615 in prevalent cancers, explore its correlation with patient mortality rates, and introduce a novel therapeutic approach to reduce LINC01615 expression. Using The Cancer Genome Atlas (TCGA) data, the expression changes of LINC01615 in various cancers were analyzed, and its relationship with patient survival rates through Cox regression analysis weas assessed. Co-expressed pathways related to LINC01615 were identified via network analysis. Potential drugs to decrease LINC01615 expression were identified using the GSE38376 study. Besides, chitosan-coated nanoparticles were fabricated and functionalized with the identified drug, Lapatinib, to examine their effect on lung cancer cell lines and changes in LINC01615 expression. Our results indicated elevated LINC01615 expression in various common cancers, particularly in lung cancer, which was associated with poor prognosis in lung, breast, and kidney cancers. Co-expression network analysis suggested links to metastasis-related genes. Lapatinib, identified through GEO data, was found to modulate LINC01615 expression effectively. Chitosan-gold nanoparticles conjugated with Lapatinib significantly reduced LINC01615 expression in lung cancer cell lines while enhancing apoptosis rates. Therefore, these nanoparticles could be considered a promising therapeutic candidate for treating cancers with overexpression of LINC01615.

Role of LINC00240 on T-helper 9 differentiation in allergic rhinitis through influencing DNMT1-dependent methylation of PU.1

BACKGROUND

Allergic rhinitis (AR) is a common allergic disease with increasing prevalence globally. However, the molecular mechanism underlying AR pathogenesis remains largely undefined.

METHODS

Peripheral blood and nasal mucosa samples obtained from patients with AR (n = 22), and ovalbumin-induced AR mouse model (n = 8 per group) were prepared for subsequent detection. qRT-PCR and western blot were used to detect the expression of LINC00240, miR-155-5p, PU.1 and other key molecules. ELISA assay and flow cytometry were employed to evaluate the secretion of IL-9 and T-helper 9 (Th9) cell ratio, respectively. Bioinformatics analysis, RNA immunoprecipitation (RIP), chromatin immunoprecipitation (ChIP) and luciferase reporter assays were employed to further elucidate the regulatory network of LINC00240/miR-155-5p/DNMT1. The methylation of PU.1 promoter was assessed by methylation-specific PCR (MSP). This signaling axis was further validated in the mouse model of AR.

RESULTS

LINC00240 was downregulated, while miR-155-5p and PU.1 were upregulated in the peripheral blood and nasal mucosa of AR patients, as well as in AR mice. This was accompanied with the increased ratio of Th9 cells and elevated IL-9 secretion. Mechanistically, LINC00240 served as a miR-155-5p sponge, and DNMT1 was a target of miR-155-5p. In addition, DNMT1 mediated the methylation of PU.1 promoter. In vivo studies verified that LINC00240 mitigated AR progression, possibly via miR-155-5p/DNMT1/PU.1-dependent Th9 differentiation.

CONCLUSION

The involvement of LINC00240 in AR pathogenesis is closely associated with Th9 differentiation through modulating DNMT1-dependent methylation of PU.1 by sponging miR-155-5p.

LncRNA PSMB8-AS1 increases glioma malignancy via the miR-382-3p/BCAT1 axis

BACKGROUND

This study aimed to investigate the specific roles of the long non-coding RNA (lncRNA) proteasome 20S subunit beta 8 (PSMB8)-antisense RNA 1 (AS1)/microRNA (miR)-382-3p/branched-chain amino acid transaminase 1 (BCAT1) interaction network in gliomas.

METHODS

Western blotting and quantitative reverse transcription-polymerase chain reaction were performed to assess the expression levels of lncRNA PSMB8-AS1, BCAT1, and miR-382-3p. Moreover, the cell proliferation, migration, and apoptosis were assessed using the cell counting kit-8, Transwell, and caspase-3 activity assays, respectively. The biological role of lncRNA PSMB8-AS1 in glioma was investigated in vivo using a xenograft mouse model. Additionally, the associations among lncRNA PSMB8-AS1, miR-382-3p, and BCAT1 were analyzed using dual-luciferase and RNA immunoprecipitation assays and bioinformatics analyses.

RESULTS

Glioma cell lines and tissues exhibited overexpression of lncRNA PSMB8-AS1 and BCAT1 and low expression of miR-382-3p. Knockdown of PSMB8-AS1 remarkably repressed the tumor growth in vivo and the migration and proliferation of glioma cells in vitro. In contrast, knockdown of lncRNA PSMB8-AS1 increased the cell apoptosis. Mechanistically, PSMB8-AS1 directly targeted miR-382-3p. By sponging miR-382-3p, lncRNA PSMB8-AS1 stimulated the migration and proliferation of glioma cells and suppressed their apoptosis. Additionally, miR-382-3p directly targeted BCAT1. Inhibition of miR-382-3p reversed the antitumor effects of BCAT1 silencing on glioma progression.

CONCLUSION

Our study revealed that lncRNA PSMB8-AS1 aggravated glioma malignancy by enhancing BCAT1 expression after competitively binding to miR-382-3p. Therefore, lncRNA PSMB8-AS1 may be a potential biomarker and therapeutic target for glioma treatment.

Epigenome editing in cancer: Advances and challenges for potential therapeutic options

Cancers are diseases caused by genetic and non-genetic environmental factors. Epigenetic alterations, some attributed to non-genetic factors, can lead to cancer development. Epigenetic changes can occur in tumor suppressors or oncogenes, or they may contribute to global cell state changes, making cells abnormal. Recent advances in gene editing technology show potential for cancer treatment. Herein, we will discuss our current knowledge of epigenetic alterations occurring in cancer and epigenetic editing technologies that can be applied to developing therapeutic options.

miR-124 as a Liquid Biopsy Prognostic Biomarker in Small Extracellular Vesicles from NSCLC Patients

Despite advances in non-small cell lung cancer (NSCLC) research, this is still the most common cancer type that has been diagnosed up to date. microRNAs have emerged as useful clinical biomarkers in both tissue and liquid biopsy. However, there are no reliable predictive biomarkers for clinical use. We evaluated the preclinical use of seven candidate miRNAs previously identified by our group. We collected a total of 120 prospective samples from 88 NSCLC patients. miRNA levels were analyzed via qRT-PCR from tissue and blood samples. miR-124 gene target prediction was performed using RNA sequencing data from our group and interrogating data from 2952 NSCLC patients from two public databases. We found higher levels of all seven miRNAs in tissue compared to plasma samples, except for miR-124. Our findings indicate that levels of miR-124, both free-circulating and within exosomes, are increased throughout the progression of the disease, suggesting its potential as a marker of disease progression in both advanced and early stages. Our bioinformatics approach identified KPNA4 and SPOCK1 as potential miR-124 targets in NSCLC. miR-124 levels can be used to identify early-stage NSCLC patients at higher risk of relapse.

Long non-coding RNA GNAS-AS1 knockdown inhibits proliferation and epithelial-mesenchymal transition of lung adenocarcinoma cells via the microRNA-433-3p/Rab3A axis

The goal of this study was to demonstrate the functions and specific mechanism of long non-coding RNA (lncRNA) GNAS-AS1 in lung adenocarcinoma. Levels of lncRNA GNAS-AS1, microRNA (miR)-433-3p, and Rab3A were assessed by quantitative real-time PCR (qRT-PCR). The target-binding sites of lncRNA GNAS-AS1, miR-433-3p, and Rab3A were predicted and confirmed by bioinformatics tool (StarBase) and a dual-luciferase reporter system. Cell proliferation and apoptosis were checked using MTT and flow cytometry, respectively. Additionally, the levels of apoptosis-related and epithelial-mesenchymal transition (EMT)-associated genes in A549 cells were analyzed by qRT-PCR and western blot. We found that lncRNA GNAS-AS1 was upregulated, miR-433-3p was low-expressed, and Rab3A was overexpressed in lung adenocarcinoma tissues and cell lines. LncRNA GNAS-AS1 interacted with miR-433-3p and negatively regulated miR-433-3p levels. Rab3A was a direct target of miR-433-3p. Downregulation of lncRNA GNAS-AS1 remarkably suppressed cell proliferation, promoted cell apoptosis, decreased B-cell lymphoma-2 (Bcl-2) expression, enhanced the Bcl-2-Associated X (Bax) level, promoted E-cadherin expression, and reduced N-cadherin and Rab3A levels. However, the miR-433-3p inhibitor reversed all these findings. Similarly, the inhibitory effects of miR-433-3p mimic on A549 cells were reversed by the Rab3A-plasmid. In conclusion, lncRNA GNAS-AS1 downregulation suppressed lung adenocarcinoma cell proliferation and EMT through the miR-433-3p/Rab3A axis.

LINC00312 Inhibits Lung Cancer Progression through the miR-3175/SEMA6A Axis

This study aims to clarify molecular mechanisms and tumor-associated functions of LINC00312 in lung cancer. GEO database was used to acquire lung cancer-related expression microarrays. Then, relevant databases were applied to predict the downstream miRNA for LINC00312 and the target mRNA for the potential miRNA, with their associations deeply confirmed through dual-luciferase and RIP assays. The expression levels of epithelial-mesenchymal transition -related proteins (N-cadherin, Vimentin, MMP-2, and MMP-9) were examined by Western blot. The proliferation, migration, and invasion were evaluated through in vitro experiments including CCK-8 and Transwell assays and further validated by nude mouse xenograft tumor experiment. LINC00312, serving as a tumor suppressor, was down-regulated in lung cancer cells. RIP assay proved that miR-3175 bound LINC00312 and SEMA6A. The dual-luciferase assay showed that miR-3175 specifically targeted SEMA6A, suppressing the expression of SEMA6A. Overexpressing LINC00312 remarkably inhibited the binding between miR-3175 and SEMA6A. Overexpressing miR-3175 or silencing SEMA6A could hamper the effects of LINC00312 on lung cancer cells. LINC00312 inhibits lung cancer occurrence and progression via the miR-3175/SEMA6A axis.

Molecular mechanism of the miR-7/BCL2L1/P53 signaling axis regulating the progression of hepatocellular carcinoma

Background

To investigate the roles of miR-7 and its potential mechanisms in hepatocellular carcinoma (HCC).

Methods

The functions of miR-7 were identified and measured by MTT [3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-di-phenytetrazoliumromide], colony formation, transwell, and flow cytometry assays. A luciferase assay was applied to verify the direct binding of miR-7 on BCL2L1 3'untranslated region (3'UTR). An in vitro experiment was then used to investigate the biological effects of miR-7 and BCL2L1. A co-immunoprecipitation (COIP) assay was used to detect the protein interaction between BCL2L1 and P53.

Results

We found that miR-7 overexpression suppressed cell proliferation, migration, and invasion in HCC. BCL2L1 was also demonstrated as a direct target gene of miR-7. This study showed that BCL2L1 could partially rescue the inhibitory effect of miR-7 on the proliferation, migration, and invasion of HCC cells. Our research showed that miR-7 could inhibit the epithelial-mesenchymal transition (EMT) pathway by regulating BCL2L1. We also further confirmed that miR-7 inhibits the proliferation, migration, and invasion of Hep3B and Huh7 cells by targeting BCL2L1. Furthermore, we observed that the BCL2L1 protein interacts with the P53 protein and BCL2L1 affects the development of liver cancer through P53. We also found that BCL2L1 could promote the invasion and migration of liver cancer cells through P53 inhibition. BCL2L1 also inhibited the expression of Caspase 3/7 in hepatoma cells by inhibiting the expression of P53.

Conclusions

Our study demonstrated that miR-7/BCL2L1/P53 may serve as a regulatory molecular axis for HCC treatment. Our results suggest that miR-7/BCL2L1/P53 may have predictive value and represent a new treatment strategy for liver cancer.

Long Noncoding RNA IPW Is a Novel Diagnostic and Predictive Biomarker in Lung Adenocarcinoma

Background: Long non-coding RNAs (lncRNAs), as functional components of the human genome, are widely involved in cell proliferation, differentiation, apoptosis, migration and invasion by several types of cancer, including lung cancer. However, the role of lncRNA IPW in lung cancer has not been fully elucidated. The aim of the present study was to characterize the expression and clinical significance of lncRNA IPW in lung cancer. Materials and Methods: IPW expression in tumor samples and cells was assessed using the Oncomine and Cancer Cell Line Encyclopedia (CCLE) database, respectively. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to determine IPW expression and microRNA-370 (miR-370) expression. The clinical significance of IPW was evaluated by Chi-square test and Kaplan-Meier pot analyses. In addition, the sulforhodamine blue (SRB) assays was used to detect cell proliferation in IPW-overexpressed A549 cells. Results: IPW expression was significantly down-regulated in NSCLC tissues and was significantly associated with many clinicopathological data, including smoking history, differentiation, pT factor, pN factor and pTNM stage (p < 0.05). Decreased IPW expression was correlated with poor survival (p = 1.5e-05) and was positively associated with first progression in patients with lung adenocarcinoma (p = 0.00041). Furthermore, IPW could inhibit A549 cell proliferation and expression of miR-370. High miR-370 expression was associated with poor overall survival (OS) among lung adenocarcinoma patients (p = 0.045). Conclusions: These findings provide evidence that down-regulation of IPW might be considered as a beneficial prognostic biomarker and that it could potentially serve as therapeutic target in lung adenocarcinoma.

LARRPM restricts lung adenocarcinoma progression and M2 macrophage polarization through epigenetically regulating LINC00240 and CSF1

BACKGROUND

Long non-coding RNAs (lncRNAs) are critical regulators in lung adenocarcinoma (LUAD). M2-type tumor-associated macrophages (TAMs) also play oncogenic roles in LUAD. However, the involvement of lncRNAs in TAM activation is still largely unknown.

METHODS

The expressions of LARRPM, LINC00240 and CSF1 were determined by RT-qPCR. The regulation of LINC00240 and CSF1 by LARRPM was investigated by RNA-protein pull-down, RNA immunoprecipitation, chromatin immunoprecipitation and bisulfite DNA sequencing. In vitro and in vivo gain- and loss-of-function assays were performed to investigate the roles of LARRPM.

RESULTS

The lncRNA LARRPM was expressed at low levels in LUAD tissues and cells. The low expression of LARRPM was correlated with advanced stage and poor survival of patients with LUAD. Functional experiments revealed that LARRPM suppressed LUAD cell proliferation, migration and invasion, and promoted apoptosis. LARRPM also repressed macrophage M2 polarization and infiltration. Taken together, LARRPM significantly restricted LUAD progression in vivo. Mechanistically, LARRPM bound and recruited DNA demethylase TET1 to the promoter of its anti-sense strand gene LINC00240, leading to a decrease in DNA methylation level of the LINC00240 promoter and transcriptional activation of LINC00240. Functional rescue assays suggested that the lncRNA LINC00240 was responsible for the roles of LARRPM in the malignant behavior of LUAD cells. LARRPM decreased the binding of TET1 to the CSF1 promoter, resulting in increased DNA methylation of the CSF1 promoter and transcriptional repression of CSF1, which is responsible for the roles of LARRPM in macrophage M2 polarization and infiltration. The TAMs educated by LUAD cells exerted oncogenic roles, which was negatively regulated by LARRPM expressed in LUAD cells.

CONCLUSIONS

LARRPM restricts LUAD progression through repressing both LUAD cell and macrophages. These data shed new insights into the regulation of LUAD progression by lncRNAs and provide data on the potential utility of LARRPM as a target for LUAD treatment.

Knockdown of Long Noncoding RNA LINC00240 Inhibits Esophageal Cancer Progression by Regulating miR-26a-5p

Background

Esophageal cancer is the most prevalent digestive system tumor. Due to a lack of characteristic symptoms and early diagnosis, a confirmed esophageal cancer is typically detected at a progressively harmful stage. Therefore, it is critical to investigate the molecular mechanisms governing the formation and progression of esophageal cancer in order to identify new treatment targets for esophageal cancer early detection.

Methods

We first screened the differentially expressed gene LINC00240 in the TCGA database. Multivariate analysis and Cox regression were performed, and a nomogram was constructed for internal validation. The correlation between LINC00240 and immune cells was analyzed using the TIMER database. The possible mechanism of action was explored through GSEA enrichment analysis. Then, in 43 esophageal cancer tissues, paracancour tissues, and cell lines, the LINC00240 expression was found. Transwell assays, CCK-8, and clone formation assays were utilized to assess the impact of LINC00240 on the metastasis of esophageal cancer cells. The binding activity of LINC00240 to downstream miRNAs was assessed using the luciferase reporter gene.

Results

TCGA database showed that LINC00240 expression was increased in cancer tissues compared to adjacent tissues. The C-index of the nomogram is 0.712 (0.666-0.758), and the prediction model has good accuracy. According to the TIMER database, the LINC00240 expression is linked to immune infiltration and may be crucial in encouraging the immune escape of tumor cells. Gene enrichment analysis depicts that LINC00240 could influence the biological events of esophageal cancer by taking part in pathways such as affecting the cell cycle. LINC00240 expression was substantially greater in the plasma of esophageal cancer patients (3.94 ± 1.55) than in the normal control group (2.13 ± 0.89). Plasma expression of LINC00240 was linked to the degree of differentiation (P=0.0345) and TNM stage (P=0.0409). Knocked down LINC00240 inhibited esophageal cancer cells proliferation, lone formation, and invasion. LINC00240 might bind itself to miR-26a-5p and influence its expression. MiR-26a-5p inhibitor can dramatically limit the ability of LINC00240 knockdown on plate colony formation and relocation of esophageal cancerous cells was demonstrated in colony formation and migration experiments.

Conclusion

LINC00240 expression is elevated in esophageal cancerous tissues, and knocking down LINC00240 decreases esophageal cancer cell proliferation, clone formation, invasion, and migration via miR-26a-5p. As a result, LINC00240 could be a novel target for esophageal cancer patients' early diagnosis and treatment.

MiRNA expression profiling in adenocarcinoma and squamous cell lung carcinoma reveals both common and specific deregulated microRNAs

The current study investigated the expression signatures of miRNAs in lung adenocarcinoma (LUAD) and squamous cell lung carcinoma (LUSC). miRNA profiling was performed using microarray in 12 LUAD and 12 LUSC samples and adjacent normal tissues. In LUAD, 107 miRNAs were significantly deregulated, whereas 235 miRNAs were deregulated in LUSC. Twenty-six miRNAs were common between the 2 cancer subtypes and 8 were prioritized for validation, in addition to 6 subtype-specific miRNAs. The RT-qPCR validation samples included 50 LUAD, 50 LUSC, and adjacent normal tissues. Eight miRNAs were validated in LUAD: 3 upregulated - miR-7-5p, miR-375-5p, miR-6785-3p, and 5 downregulated - miR-101-3p, miR-139-5p, miR-140-3p, miR-144-3p, miR-195-5p. Ten miRNAs were validated in the LUSC group: 3 upregulated - miR-7-5p, miR-21-3p, miR-650, and 7 downregulated - miR-95-5p, miR-140-3p, miR-144-3p, miR-195-5p, miR-375, miR-744-3p, and miR-4689-3p. Reactome pathway analysis revealed that the target genes of the deregulated miRNAs in LUAD were significantly enriched in cell cycle, membrane trafficking, gene expression processes, and EGFR signaling, while in LUSC, they were enriched in the immune system, transcriptional regulation by TP53, and FGFR signaling. This study identified distinct miRNA profiles in LUSC and LUAD, which are common and specific miRNAs that could be further investigated as biomarkers for diagnosis and prognosis.

Role of MicroRNA-7 (MiR-7) in Cancer Physiopathology

miRNAs are non-coding RNA sequences of approximately 22 nucleotides that interact with genes by inhibiting their translation through binding to their 3′ or 5′ UTR regions. Following their discovery, the role they play in the development of various pathologies, particularly cancer, has been studied. In this context, miR-7 is described as an important factor in the development of cancer because of its role as a tumor suppressor, regulating a large number of genes involved in the development and progression of cancer. Recent data support the function of miR-7 as a prognostic biomarker in cancer, and miR-7 has been proposed as a strategy in cancer therapy. In this work, the role of miR-7 in various types of cancer is reviewed, illustrating its regulation, direct targets, and effects, as well as its possible relationship to the clinical outcome of cancer patients.

lncRNA NBAT1 Inhibits Cell Metastasis and Promotes Apoptosis in Endometrial Cancer by Sponging miR-21-5p to Regulate PTEN

Objective

Long noncoding RNA neuroblastoma-associated transcript 1 (NBAT1) is implicated in the progression of various cancers. Nevertheless, its biological function in endometrial cancer (EC) remains unknown.

Methods

The levels of NBAT1, miR-21-5p, and PTEN in EC cells and EC tissues were examined by RT-qPCR. Western blot was carried out to assess the protein expression of PTEN. The dual-luciferase reporter assay was conducted to explore the interactions among NBAT1, miR-21-5p, and PTEN. The effect of NBAT1 on EC proliferation, metastasis, and apoptosis was evaluated by CCK-8, transwell assays, wound healing, and flow cytometry. miR-21-5p mimics or NBAT1+miR-21-5p were transfected into HEC-1A and Ishikawa cells to investigate whether NBAT1 regulated EC tumorigenesis via sponging miR-21-5p.

Results

NBAT1 is downregulated, and miR-21-5p is upregulated in EC cells and tumor tissues. Overexpression of NBAT1 inhibits the proliferation, migration, and invasion abilities of EC cells and facilitated apoptosis. NBAT1 directly binds and negatively regulates miR-21-5p in EC. miR-21-5p mimics reverses the effect of lncRNA NBAT1 overexpression on the proliferation and migration of EC cells. PTEN is a downstream gene of miR-21-5p. lncRNA NBTA1 elevates PTEN expression via sponging miR-21-5p.

Conclusions

lncRNA NBAT1 acts as a tumor suppressor in EC via regulating PTEN through sponging miR-21-5p.

Long non-coding RNAs and exosomal lncRNAs: Potential functions in lung cancer progression, drug resistance and tumor microenvironment remodeling

Among the different kinds of tumors threatening human life, lung cancer is one that is commonly observed in both males and females. The aggressive behavior of lung cancer and interactions occurring in tumor microenvironment enhances the malignancy of this tumor. The lung tumor cells have demonstrated capacity in developing chemo- and radio-resistance. LncRNAs are a category of non-coding RNAs that do not encode proteins, but their aberrant expression is responsible for tumor development, especially lung cancer. In the present review, we focus on both lncRNAs and exosomal lncRNAs in lung cancer, and their ability in regulating proliferation and metastasis. Cell cycle progression and molecular mechanisms related to lung cancer metastasis such as EMT and MMPs are regulated by lncRNAs. LncRNAs interact with miRNAs, STAT, Wnt, EZH2, PTEN and PI3K/Akt signaling pathways to affect progression of lung cancer cells. LncRNAs demonstrate both tumor-suppressor and tumor-promoting functions in lung cancer. They can be considered as biomarkers in lung cancer and especially exosomal lncRNAs present in body fluids are potential tools for minimally invasive diagnosis. Furthermore, we discuss regulation of lncRNAs by anti-cancer drugs and genetic tools as well as the role of these factors in therapy response of lung cancer cells.

LINC00240 knockdown inhibits nasopharyngeal carcinoma progress by targeting miR-26a-5p

Objective

This study intended to explore the regulatory functions of LINC00240 on nasopharyngeal carcinoma (NPC).

Methods

MiR‐26a‐5p inhibitor, mimic, and siLINC00240 were transfected into NPC cells. QRT‐PCR was employed to assess miR‐26a‐5p and LINC00240 expressions. The targeting relationship of LINC00240 and miR‐26a‐5p was analyzed through dual luciferase reporter and RNA immunoprecipitation assay. Cell counting kit‐8 assay, colony formation assay, flow cytometry assay, wound healing assay, Transwell assay and in vitro angiogenesis assay were adopted for the evaluation of the effects of LINC00240 or miR‐26a‐5p and LINC00240 on NPC cells regarding cell proliferation, apoptosis and cycle, migration, invasion, and angiogenesis. EZH2, cell cycle, and epithelial‐mesenchymal transition (EMT)‐related protein expression was tested through Western blot.

Results

LINC00240 had a high expression in NPC tissues and cell lines. Silenced LINC00240 significantly suppressed the 5‐8F and HK1 cell proliferation, invasion, migration, and angiogenesis, but raised cell apoptosis, and cells were blocked in G0/G1 phase. MiR‐26a‐5p was a target of LINC00240. MiR‐26a‐5p upregulation suppressed the NPC cell proliferation, migration, invasion, angiogenesis, N‐cadherin and EZH2 expression, while it elevated apoptosis and p21, p27 and E‐cadherin expressions, whereas miR‐26a‐5p downregulation performed conversely. LINC00240 knockdown partially offset the effects of miR‐26a‐5p downregulation on cell proliferation, migration, invasion, angiogenesis, apoptosis, and EZH2.

Conclusion

LINC00240 knockdown restrained cell proliferation, invasion, migration, and angiogenesis, while it advanced apoptosis via miR‐26a‐5p in NPC by EZH2 inhibition.

MiR-7-5p suppresses invasion via downregulation of the autophagy-related gene ATG7 and increases chemoresistance to cisplatin in BCa

Bladder cancer (BCa) is one of the most common cancers in men and is a major threat to the lives and health of older men. Many studies have shown that miR-7, as an important tumor suppressor gene, could directly inhibit some pathways involved in the development of cancer. MiR-7-5p, which was assessed in this study, consists of one arm of miR-7 and acts as a cancer suppressor gene in multiple cancer types. Autophagy, as a common biological process, plays dual roles in the process of cancer. Chemotherapy resistance is a problem in the treatment of BCa. In this study, the data showed that miR-7-5p was obviously down-regulated in BCa tissues and cells compared to their respective controls. In addition, miR-7-5p mimic effectively inhibited migration, invasion and autophagy both in vitro and in vivo. In the mechanistic study, miR-7-5p targeted autophagy-related gene ATG7 to inhibit its expression, which in turn inhibited autophagy. Finally, the migration of BCa cells was inhibited, and chemosensitivity was improved. Overall, our results provide evidence of the role of miR-7-5p as a cancer suppressor gene in BCa and provide new opportunities for the treatment of BCa.

Long non-coding RNA LINC00240 promotes gastric cancer progression via modulating miR-338-5p/METTL3 axis

Gastric cancer (GC) is a common cancer with high incidence. Understanding the epidemiology and physiopathology of GC is crucial for formulating novel therapeutic strategies. Recent studies have implicated long non-coding RNA LINC00240, miR-338-5p and methyltransferase-like 3 (METTL3) in the progression of GC. In this study, we investigated the functional role of LINC00240/miR-338-5p/METTL3 axis in regulating the aggressiveness of GC cells. We first demonstrated that LINC00240 was upregulated in GC tissues and GC cell lines. High expression of LINC00240 was associated with advanced TNM stage, a higher extent of distant metastasis and lymph nodes metastasis, and the poor overall and disease-free survival of the patients. In GC cell lines, the knockdown of LINC00240 inhibited GC cell proliferation and migration, but induced cell apoptosis. We further identified and validated the functional interaction between LINC00240 and miR-338-5p. miR-338-5p seemed to function as a downstream target negatively regulated by LINC00240, and miR-338-5p could target METTL3 at 3ʹ UTR to downregulate its expression. In GC tissues, the expression of miR-338-5p was negatively correlated with LINC00240, and the expression of miR-338-5p was negatively correlated with METTL3. Importantly, miR-338-5p inhibitor or METTL3 overexpression could rescue the inhibitory effect of LINC00240 knockdown on cell proliferation and migration, and inhibit the apoptosis induction in GC cells. Taken together, our data imply that the upregulation of LINC00240 in GC cells promotes the malignant phenotype by modulating miR-338-5p/METTL3 axis, which could serve as potential therapeutic targets for GC treatment.

Linc00467 promotes invasion and inhibits apoptosis of head and neck squamous cell carcinoma by regulating miR-1285-3p/TFAP2A

OBJECTIVE

To explore the invasion and apoptosis of head and neck squamous cell carcinoma (HNSCC) regulated by Linc00467 through the miR-1285-3p/TFAP2A axis.

METHODS

qRT-PCR was used to detect the expressions of Linc00467, miR-1285-3p, and TFAP2A in tissues and cells of HNSCC patients. The targeting relationships between Linc00467 and miR-1285-3p, miR-1285-3p, and TFAP2A were verified by dual-luciferase reporter assay. Transfection and grouping were carried out, after HNSCC cell lines were screened. Transwell assay and flow cytometry were used to test cell invasion and apoptosis, respectively.

RESULTS

Compared with normal tissues adjacent to the tumor, the expressions of Linc00467 and TFAP2A increased significantly in cancer tissues, while the expression of miR-1285-3p decreased (all P<0.05). Compared with the si-NC group, the invasion of the si-Linc00467 group decreased and the apoptosis rate increased (both P<0.05). In HNSCC cells, over-expression of Linc00467 promoted increased cell invasion and decreased apoptosis rate, which could be partially rescued by over-expression of miR-1285-3p (all P<0.05). Over-expression of miR-1285-3p caused decreased cell invasion and increased apoptosis rate, which was partially reversed by over-expression of TFAP2A (all P<0.05).

CONCLUSION

Linc00467 can be used as ceRNA to adsorb miR-1285-3p to regulate the expression of TFAP2A, promote invasion and inhibit apoptosis of HNSCC cells. Linc00467 inhibitors may become one of the targeted therapeutic drugs for HNSCC.

MiR-7 in Cancer Development

MicroRNAs (miRNAs) are short non-coding RNA involved in the regulation of specific mRNA translation. They participate in cellular signaling circuits and can act as oncogenes in tumor development, so-called oncomirs, as well as tumor suppressors. miR-7 is an ancient miRNA involved in the fine-tuning of several signaling pathways, acting mainly as tumor suppressor. Through downregulation of PI3K and MAPK pathways, its dominant role is the suppression of proliferation and survival, stimulation of apoptosis and inhibition of migration. Besides these functions, it has numerous additional roles in the differentiation process of different cell types, protection from stress and chromatin remodulation. One of the most investigated tissues is the brain, where its downregulation is linked with glioblastoma cell proliferation. Its deregulation is found also in other tumor types, such as in liver, lung and pancreas. In some types of lung and oral carcinoma, it can act as oncomir. miR-7 roles in cell fate determination and maintenance of cell homeostasis are still to be discovered, as well as the possibilities of its use as a specific biotherapeutic.