miR-641 Functions as a Tumor Suppressor by Targeting MDM2 in Human Lung Cancer

The miR-641-STIM1 and SATB1 axes play important roles in the regulation of the Th17/Treg balance in ITP

Immune thrombocytopenia (ITP) is an autoimmune disease caused by T-cell dysfunction. Recently, several studies have shown that a disturbed Th17/Treg balance contributes to the development of ITP. MicroRNAs (miRNAs) are small noncoding RNA moleculesthat posttranscriptionally regulate gene expression. Emerging evidences have demonstrated that miRNAs play an important role in regulating the Th17/Treg balance. In the present study, we found that miR-641 was upregulated in ITP patients. In primary T cells, overexpression of miR-641 could cause downregulation of its target genes STIM1 and SATB1, thus inducing a Th17 (upregulated)/Treg (downregulated) imbalance. Inhibition of miR-641 by a miR-641 sponge in primary T cells of ITP patients or by antagomiR-641 in an ITP murine model could cause upregulation of STIM1 and SATB1, thus restoring Th17/Treg homeostasis. These results suggested that the miR-641-STIM/SATB1 axis plays an important role in regulating the Th17/Treg balance in ITP.

Molecular mechanisms underlying the regulation of tumour suppressor genes in lung cancer

Tumour suppressor genes play a cardinal role in the development of a large array of human cancers, including lung cancer, which is one of the most frequently diagnosed cancers worldwide. Therefore, extensive studies have been committed to deciphering the underlying mechanisms of alterations of tumour suppressor genes in governing tumourigenesis, as well as resistance to cancer therapies. In spite of the encouraging clinical outcomes demonstrated by lung cancer patients on initial treatment, the subsequent unresponsiveness to first-line treatments manifested by virtually all the patients is inherently a contentious issue. In light of the aforementioned concerns, this review compiles the current knowledge on the molecular mechanisms of some of the tumour suppressor genes implicated in lung cancer that are either frequently mutated and/or are located on the chromosomal arms having high LOH rates (1p, 3p, 9p, 10q, 13q, and 17p). Our study identifies specific genomic loci prone to LOH, revealing a recurrent pattern in lung cancer cases. These loci, including 3p14.2 (FHIT), 9p21.3 (p16INK4a), 10q23 (PTEN), 17p13 (TP53), exhibit a higher susceptibility to LOH due to environmental factors such as exposure to DNA-damaging agents (carcinogens in cigarette smoke) and genetic factors such as chromosomal instability, genetic mutations, DNA replication errors, and genetic predisposition. Furthermore, this review summarizes the current treatment landscape and advancements for lung cancers, including the challenges and endeavours to overcome it. This review envisages inspired researchers to embark on a journey of discovery to add to the list of what was known in hopes of prompting the development of effective therapeutic strategies for lung cancer.

Knockdown of circ_CLIP2 regulates the proliferation, metastasis and apoptosis of glioma cells through miR-641/EPHA3/STAT3 axis

A great amount of reaches have confirmed that circular RNAs (circRNAs) are novel regulators in glioma progression. Here, our work aimed to probe the specific role of circ_CLIP2 in glioma. The mRNA and protein expressions were analyzed by qRT-PCR and western blot, respectively. Cell viability, migration, invasion and apoptosis were examined by MTT assay, tranwell and flow cytometry assays, respectively. Moreover, the binding relationships between circ_CLIP2, microRNA (miR)-641 and erythropoietin-producing human hepatocellular (Eph)A3 were verified by dual luciferase reporter gene assay and/or RIP assay. The following data showed that circ_CLIP2 and EPHA3 were markedly increased in glioma tissues and cells, while miR-647 was downregulated. Gain- and loss-of-function experiments discovered that circ_CLIP2 knockdown remarkably inhibited cell proliferation, migration and invasion and promoted cell apoptosis of glioma cells, while these effects of circ_CLIP2 knockdown were abolished by miR-641 inhibition. Circ_CLIP2 was proved as a sponge of miR-641 to competitively upregulate EPHA3 expression. In addition, EPHA3 overexpression could abolish the inhibitory effects of miR-641 overexpression on the malignant behaviors of glioma cells by activating the signal transducer and activator of transcription 3 (STAT3). These findings elucidated that circ_CLIP2 knockdown suppressed glioma development by regulation of the miR-641/EP HA3/STAT3 axis, which provided a novel mechanism for understanding the pathogenesis of glioma.

Bioinformatics and Expression Analyses of miR-639, miR-641, miR-1915-3p and miR-3613-3p in Colorectal Cancer Pathogenesis

Objectives: MicroRNAs (miRNAs) have important function in cancer development and progression. This study aims to determine the expression levels of miR-639, miR-641, miR-1915-3p, and miR-3613-3p in tissues of colorectal cancer (CRC) patients and the role of these miRNAs in the CRC pathogenesis. Methods: Tumor and non-tumor tissues were collected from a total of 59 CRC patients. qRT-PCR was used to identify the expressions of miR-639, miR-641, miR-1915-3p and miR-3613-3p. Through bioinformatics analysis, the target genes of miRNAs were identified by using DIANA mirPath v.3. Signaling pathways were generated using KEGG pathway database. Biological pathway, cellular component analysis, and analysis of Protein-Protein Interactions (PPI) Networks were performed using FunRich and STRING database. Results: Our findings revealed that miR-639, miR-641 and miR-3613-3p were significantly downregulated, and miR-1915-3p was significantly upregulated in tumor tissues compared to non-tumor tissues (p˂0.05). Furthermore, MAPK signaling pathway was the most enriched KEGG pathway regulated by miR-639, miR-641, miR-1915-3p and miR-3613-p. According to the FunRich, it was demonstrated that the targeted genes by miRNAs related to the cellular component and biological pathways such as beta-catenin-TCF7L2, axin-APC-beta-catenin-GSK3B complexes, Arf6 signaling, Class I PI3K signaling, etc. And, by the PPI analysis, it was established that the target genes were clustered on CTNNB1 and KRAS. Conclusions: These outcomes imply that miR-639, miR-641 and miR-3613-3p have tumor suppressor roles, while miR-1915-3p has an oncogenic role in the pathogenesis of CRC. According to the results of the current study, dysregulated miR-639, miR-641, miR-1915-3p, and miR-3613-3p might contribute to the development of CRC.

A Tumor and Immune-Related Micro-RNA Signature Predicts Relapse-Free Survival of Melanoma Patients Treated with Ipilimumab

Despite the unprecedented advances in the treatment of melanoma with immunotherapy, there continues to be a major need for biomarkers of clinical benefits and immune resistance associated with immune checkpoint inhibitors; microRNA could play a vital role in these efforts. This study planned to identify differentially expressed miRNA molecules that may have prognostic value for clinical benefits. Patients with surgically operable regionally advanced melanoma were treated with neoadjuvant ipilimumab (10 mg/kg intravenously every 3 weeks × two doses) bracketing surgery. Tumor biospecimens were obtained at baseline and surgery, and microRNA (miRNA) expression profiling was performed on the tumor biopsies. We found that an expression profile consisting of a 4-miRNA signature was significantly associated with improved relapse-free survival (RFS). The signature consisted of biologically relevant molecules previously reported to have prognostic value in melanoma and other malignancies, including miR-34c, miR-711, miR-641, and miR-22. Functional annotation analysis of target genes for the 4-miRNA signature was significantly enriched for various cancer-related pathways, including cell proliferation regulation, apoptosis, the MAPK signaling pathway, and the positive regulation of T cell activation. Our results presented miRNAs as potential biomarkers that can guide the treatment of melanoma with immune checkpoint inhibitors. These findings warrant further investigation in relation to CTLA4 blockade and other immune checkpoint inhibitors. ClinicalTrials.gov NCT00972933.

The Importance of the Immune System and Molecular Cell Signaling Pathways in the Pathogenesis and Progression of Lung Cancer

Lung cancer is a disease that in recent years has become one of the greatest threats to modern society. Every year there are more and more new cases and the percentage of deaths caused by this type of cancer increases. Despite many studies, scientists are still looking for answers regarding the mechanisms of lung cancer development and progression, with particular emphasis on the role of the immune system. The aim of this literature review was to present the importance of disorders of the immune system and the accompanying changes at the level of cell signaling in the pathogenesis of lung cancer. The collected results showed that in the process of immunopathogenesis of almost all subtypes of lung cancer, changes in the tumor microenvironment, deregulation of immune checkpoints and abnormalities in cell signaling pathways are involved, which contribute to the multistage and multifaceted carcinogenesis of this type of cancer. We, therefore, suggest that in future studies, researchers should focus on a detailed analysis of tumor microenvironmental immune checkpoints, and to validate their validity, perform genetic polymorphism analyses in a wide range of patients and healthy individuals to determine the genetic susceptibility to lung cancer development. In addition, further research related to the analysis of the tumor microenvironment; immune system disorders, with a particular emphasis on immunological checkpoints and genetic differences may contribute to the development of new personalized therapies that improve the prognosis of patients.

MicroRNA-641 Inhibits Endometrial Cancer Progression via Targeting AP1G1

MicroRNA-641 (miR-641) was significantly decreased in various cancers, but its roles in endometrial cancer (EC) remain unclear. We explored the influences of miR-641 on the EC cells. In our study, the miR-641 expression was reduced in EC cells. Overexpression of miR-641 inhibited viability and proliferation of HEC-1A and HECCL-1 cells by CCK-8 and colony formation assays. Additionally, flow cytometry revealed that overexpression of miR-641 could remarkably promote apoptosis and arrest the cell cycle at the G1 phase of HEC-1A and HECCL-1 cells. Besides, forced expression of miR-641 suppressed the migration and invasion of HEC-1A and HECCL-1 cells as evidenced by wound healing and transwell assay. Moreover, AP1G1 was confirmed as a target gene of miR-641 by StarBase prediction and DLR assay and their expressions were negatively correlated. Overexpression of AP1G1 neutralized the roles of miR-641 mimic on the viability, proliferation, apoptosis, and migration of HEC-1A and HECCL-1 cells. Our findings illustrated that miR-641 was reduced in the EC cells and AP1G1 antagonized the miR-641 mimic-induced inhibition of the EC progression in vitro. Therefore, miR-641 may emerge as an effective molecule for EC treatment.

MicroRNA-877-5p Inhibits Cell Progression by Targeting FOXM1 in Lung Cancer

Background

Many researches revealed that microRNAs (miRNAs) function as potential oncogene or tumor suppressor gene. As an antioncogene, miR-877-5p was reduced in many tumors.

Objective

This research aimed to explore the biological role and mechanisms of miR-877-5p, which may help patients with non-small-cell lung cancer (NSCLC) find effective therapeutic targets.

Methods

The downstream targets of miR-877-5p were predicted by Bioinformatics software. RT-qPCR and western blot were employed to analyze the gene levels. The impacts of miR-877-5p and FOXM1 were assessed by cell function experiments.

Results

The miR-877-5p was reduced in NSCLC. In addition to this, it also inhibited cell progression of NSCLC cells in vitro. Moreover, the upregulation of FOXM1 expression restored the inhibitory effect of enhancement of miR-877-5p.

Conclusions

Taken together, miR-877-5p inhibited cell progression by directly targeting FOXM1, which may provide potential biomarkers for targeted therapy of NSCLC.

LINC00665 sponges miR-641 to promote the progression of breast cancer by targeting the SNF2-related CREBBP activator protein (SRCAP)

The regulatory network of competing endogenous RNAs (ceRNA) exists widely in tumors and affects the expression of cancer-related genes, thus playing an important role in the development and prognosis of human tumors. In this research, we explored the role and mechanism of LINC00665 as a ceRNA in breast cancer. We analyzed the expression and targets of LINC00665 in breast cancer using bioinformatics, and detected their effects on breast cancer cells by CCK8, transwell, colony formation and flow cytometry assays. From our results, LINC00665 knockdown suppressed the proliferation, migration and invasion and induced the apoptosis through inactivating the AKT/mTOR signaling pathway in MCF7 and MDA-MB-231 cells. LINC00665 had five potential downstream target miRNAs (miR-542-3p, miR-624-5p, miR-641, miR-425-5p, and miR-30-3p). In dual-luciferase report gene assay, the fluorescence activity of cells transfected with miR-641 mimics decreased, and the expression of miR-641 decreased significantly after knocking down LINC00665. miR-641 mimics significantly inhibited cell proliferation and invasion in MCF7 and MDA-MB-231 cells. We detected five potential direct targets of miR-641 using qPCR (SRCAP, SIKE1, NADK, KHDC4, and HSPG2). SRCAP expression decreased significantly in miR-641 overexpression cells and the binding of SRCAP’s 3ʹUTR and miR-641 was further confirmed by dual-luciferase report gene assay. SRCAP blocked the proliferation and invasion inhibition induced by miR-641 or si-LINC00665 in MCF7 and MDA-MB-231 cells. In conclusion, LINC00665 could promote the survival and metastasis of breast cancer cells through sponging miR-641 and targeting SRCAP. This research provided new potential targets for targeted therapy in human breast cancer.

NR2F1-AS1 Acts as an Oncogene in Breast Cancer by Competitively Binding with miR-641

BACKGROUND

Long noncoding RNA (lncRNA) NR2F1-AS1 has been previously reported to be dysregulated in human cancers and implicated in the tumorigenesis and development of tumors. In this research, we detected the expression level and biological function of NR2F1-AS1 in breast cancer (BC).

METHODS

The expression of NR2F1-AS1 in BC tissues and cell lines was determined by qRT-PCR analysis. The associations of NR2F1-AS1 expression with clinical characteristics and survival rate of BC patients were also analyzed. Cell proliferation, migration, and invasion were measured by the CCK-8 and Transwell assay.

RESULTS

The results revealed that the total survival time of BC patients with high NR2F1-AS1 expression was lower than that of BC patients with low NR2F1-AS1 expression. Moreover, functional experiments demonstrated that knockdown of NR2F1-AS1 inhibited BC cell viability, migration, and invasion abilities, whereas overexpression of NR2F1-AS1 had the opposite effect. Mechanistic investigation revealed that NR2F1-AS1 can competitively bind with microRNA-641 (miR-641) in BC. These results revealed that NR2F1-AS1 functioned as an oncogene by sponging miR-641 expression in BC cell progression. Moreover, miR-641 was negatively correlated with NR2F1-AS1 in BC tissues.

CONCLUSION

Hence, NR2F1-AS1 was found to act as an oncogene in breast cancer by suppressing miR-641. We suggested that NR2F1-AS1 could be a potential biomarker for BC diagnosis and therapy.

miR-641 Inhibited Cell Proliferation and Induced Apoptosis by Targeting NUCKS1/PI3K/AKT Signaling Pathway in Breast Cancer

Objective

Studies revealed an important role of microRNAs (miRNAs) in multiple cancers, including breast cancer. In the present study, we evaluated the role and function of miR-641 in breast cancer.

Methods

The expression level of miR-641 in breast cancer cell lines (Hs-578T, MCF7, HCC1937, and MAD-MB-231) was determined by real-time PCR. Functional analyses, including CCK-8 assay, transwell assay, wound-healing assay, and apoptosis detection, were carried out to explore the roles of miRNA-641 in malignant behaviors of breast cancer. Luciferase report assay was used to investigate the regulatory association of miRNA-641 with its potential targets.

Results

The expression levels of miR-641 were downregulated, while the expression levels of nuclear casein kinase and cyclin-dependent kinase substrate 1 (NUCKS1) were increased in breast cancer cell lines. The in vitro results showed that miR-641 repressed proliferation and migration/invasion and promoted apoptosis of breast cancer cells. NUCKS1, a positive regulator of phosphatidylinositol-3-kinases (PI3K)/protein-serine-threonine kinase (AKT) pathway, was confirmed as a direct target of miR-641. The of treatment of the PI3K agonist, 740Y-P, could abrogate the antioncogenic potentials of miR-641 in breast cancer cells.

Conclusion

miR-641 functioned as a tumor suppressor through the PI3K/AKT signaling pathway via targeting NUCKS1 in breast cancer.

N1, N12-Diacetylspermine Is Elevated in Colorectal Cancer and Promotes Proliferation through the miR-559/CBS Axis in Cancer Cell Lines

N1, N12-Diacetylspermine (DiAcSpm) has been reported to be upregulated in the urine of cancer patients. Mass spectrometry has shown elevated DiAcSpm expressions in colorectal cancer (CRC) tissues. However, the diagnostic application of DiAcSpm is not available due to a lack of diagnostic grade antibodies. Also, its biological roles in CRC cells remain unexplored. In the present study, we developed an antibody that directly detected DiAcSpm expression in paraffin-embedded tissues. We also characterized its biological characteristics and underlying mechanisms. Polyclonal antibodies were generated by immunizing animals with a synthetic product of DiAcSpm. Antibody DAS AB016 showed strong sensitivity against DiAcSpm in CRC tissues. Immunohistochemistry results showed that DiAcSpm expression was significantly elevated in CRC tissues. High levels of DiAcSpm correlated with the clinical stage and Ki67 index. DiAcSpm treatment increased levels of proliferation, cell cycle progression, and cyclin D1 and cyclin E proteins in CRC cell lines, SW480 and Caco-2. DiAcSpm also upregulated ATP production in these two cell lines. RNA-sequencing showed that DiAcSpm downregulated miR-559, which was confirmed using RT-qPCR. The luciferase reporter assay, western blotting, and RT-qPCR showed that cystathionine β-synthase (CBS) was the target of miR-559. miR-559 inhibited, while CBS accelerated, CRC proliferation. In addition, CBS siRNA knockdown blocked the biological effects of DiAcSpm on CRC cells. In conclusion, DiAcSpm was found to be increased in CRC tissues using a newly developed antibody. DiAcSpm accelerated CRC proliferation by regulating the miR-559/CBS axis.

The COX10-AS1/miR-641/E2F6 Feedback Loop Is Involved in the Progression of Glioma

Glioma is the most common primary tumour of the central nervous system and is considered one of the greatest challenges for neurosurgery. Mounting evidence has shown that lncRNAs participate in various biological processes of tumours, including glioma. This study aimed to reveal the role and relevant mechanism of COX10-AS1 in glioma. The expression of COX10-AS1, miR-641 and E2F6 was measured by qRT-PCR and/or western blot. Clone formation assays, EdU assays, Transwell assays and tumour xenograft experiments were performed to evaluate the effects of COX10-AS1, miR-641 and E2F6 on glioma proliferation, migration and invasion. Luciferase reporter assays, RNA pull-down assays and ChIP assays were conducted to analyse the relationship among COX10-AS1, miR-641 and E2F6. We demonstrated that COX10-AS1 was upregulated in glioma tissues and cell lines, which was related to the grade of glioma and patient survival. Next, through functional assays, we found that COX10-AS1 influenced the proliferation, migration and invasion of glioma cell lines. Then, with the help of bioinformatics analysis, we confirmed that COX10-AS1 regulated glioma progress by acting as a sponge of miR-641 to regulate E2F6. Moreover, further study indicated that E2F6 could promote COX10-AS1 expression by binding to its promoter region. Taken together, the data indicated that COX10-AS1 acts as an oncogene in combination with COX10-AS1/miR-641/E2F6 in glioma, which may be beneficial to the diagnosis and treatment of glioma.

Circular RNA circSETD3 hampers cell growth, migration, and stem cell properties in bladder cancer through sponging miR-641 to upregulate PTEN

Bladder cancer (BLCA) is a common malignant urothelial cancer in the world. Although circular RNAs (circRNAs) involve in regulating BLCA progression, the role of a novel circular RNA circSETD3 in regulating BLCA pathogenesis has not been studied. The expression of circSETD3, miR-641, PTEN mRNA in BLCA tissues and cell lines were measured using RT-qPCR. The gain-of-function experiments were performed in vitro and in vivo to detect the effects of circSETD3 on cell proliferation, migration, EMT, and stemness maintenance. Besides, rescue experiments were performed to demonstrate the regulatory mechanism of circSETD3/miR-641/PTEN in BLCA cell malignant phenotypes in vitro. CircSETD3 was remarkably downregulated in the cancerous clinical tissues and cell lines, in contrast with their normal counterparts, and circSETD3 tended to be deficient in BLCA patients with larger tumor size, advanced clinical stages, positive lymph metastasis and worse prognosis. In addition, circular isoforms of circSETD3 were more resistant to RNase R+ and actinomycetes D treatment compared to their linear isoforms, and circSETD3 mainly distributed in the cytoplasm of the BLCA cells. Further gain-of-function experiments showed that circSETD3 acted as a tumor suppressor to suppress BLCA cell proliferation, migration, EMT and stemness, and the underlying mechanisms had also been elucidated. Mechanistically, circSETD3 sponged miR-641 to upregulate PTEN, resulting in the blockage of BLCA progression. Our findings indicated that circSETD3 acted as a vital tumor suppressor in BLCA via regulating the miR-641/PTEN axis.

MicroRNAs as Therapeutic Targets for Anticancer Drugs in Lung Cancer Therapy

MicroRNAs (miRNAs) are short, non-coding RNA molecules that regulate gene expression by translational repression or deregulation of messenger RNAs. Accumulating evidence suggests that miRNAs play various roles in the development and progression of lung cancers. Although their precise roles in targeted cancer therapy are currently unclear, miRNAs have been shown to affect the sensitivity of tumors to anticancer drugs. A large number of recent studies have demonstrated that some anticancer drugs exerted antitumor activities by affecting the expression of miRNAs and their targeted genes. These studies have elucidated the specific biological mechanism of drugs in tumor suppression, which provides a new idea or basis for their clinical application. In this review, we summarized the therapeutic mechanisms of drugs in lung cancer therapy through their effects on miRNAs and their targeted genes, which highlights the roles of miRNAs as targets in lung cancer therapy.

Long non-coding RNA MIAT regulates ox-LDL-induced cell proliferation, migration and invasion by miR-641/STIM1 axis in human vascular smooth muscle cells

Background

Atherosclerosis (AS) is a primary cause of coronary heart and vascular diseases. Long non-coding RNAs (lncRNAs) are indicated to regulate AS progression. This study aimed to reveal the biological roles of lncRNA myocardial infarction associated transcript (MIAT) in oxidized low-density lipoprotein (ox-LDL)-induced human vascular smooth muscle cells (VSMCs).

Methods

The RNA levels of MIAT, microRNA-641 (miR-641) and stromal interaction molecule 1 (STIM1) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The protein levels were determined by western blot analysis. Cell proliferation was assessed by cell colony formation and DNA content quantitation assays. Cell migration and invasion were demonstrated by wound-healing and transwell assays. The putative binding relationships between miR-641 and MIAT or STIM1 were predicted by starbase online database, and identified by dual-luciferase reporter and RNA immunoprecipitation assays.

Results

MIAT and STIM1 expression were substantially upregulated, whereas miR-641 expression was downregulated in ox-LDL-induced VSMCs compared with control groups. Functionally, MIAT silencing attenuated ox-LDL-induced cell proliferation, migration and invasion in VSMCs; however, these effects were impaired by miR-641 inhibitor. STIM1 overexpression also restrained miR-641-mediated impacts on cell proliferation and metastasis under ox-LDL. Mechanistically, MIAT acted as a sponge for miR-641, and miR-641 was associated with STIM1.

Conclusions

MIAT silencing hindered ox-LDL-induced cell proliferation, migration and invasion by downregulating STIM1 expression through binding to miR-641 in VSMCs. The mechanism provided us with a new target for AS therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02048-9.

Effect of the circCDR1as/miR-641/XIAP regulatory axis on the proliferation and invasion of the prostate cancer PC-3 cell line

Prostate cancer is one of the most common malignant tumors in men. Patients with local infiltration and distant metastasis often have a poor prognosis. The present study aimed to investigate the expression and regulatory mechanism of the circular RNA cerebellar degeneration-related protein 1, anti-sense (circCDR1as) in prostate cancer cell lines. MicroRNAs (miRNAs) regulated by circCDR1as and target genes regulated by miRNAs were predicted using bioinformatics software. Prostate cancer cell lines (LNCaP, 22Rv1 and PC-3), a normal prostate epithelial cell line (RWPE-1) and a human embryonic kidney cell line (293T) were cultured. Relative gene expression was detected using reverse transcription PCR. Small interfering RNAs (siRNAs) targeting circCDR1as and X-linked inhibitor of apoptosis protein (XIAP) and miRNA mimics were designed and transfected into the cell lines using Lipofectamine^® 3000. Cell invasion was determined using a Transwell assay, the cell proliferation rate was detected using an MTT assay and cell migration was examined using a scratch assay. Relative protein expression was detected using western blotting. Double fluorescent reporter gene vectors and an anti-Ago2 RNA-binding protein immunoprecipitation assay were used to verify binding. Bioinformatics analyses indicated that there was a binding site between miR-641 and circCDR1as and between miR-641 and XIAP. The expression of circCDR1as and XIAP was higher and the expression of miR-641 was lower in the prostate cancer cell lines compared with the normal prostate epithelial cell line. After effectively reducing the expression of circCDR1as and XIAP and increasing the expression of miR-641 in PC-3 cells, the proliferation, invasion and migration of PC-3 cells were effectively inhibited. circCDR1as could bind to miR-641, which targeted the 3′-untranslated region of XIAP. Reducing the expression of circCDR1 promoted the expression of miR-641 and inhibited the expression of XIAP. Overall, the circCDR1as/miR-641/XIAP regulatory axis plays a role in the invasion and migration of the prostate cancer PC-3 cell line.

Long non-coding RNA LINC01194 promotes the proliferation, migration and invasion of lung adenocarcinoma cells by targeting miR-641/SETD7 axis

Background

It is increasingly evidenced that long non-coding RNAs (lncRNAs) play an important role in various diseases. LncRNA LINC01194 acts as an oncogene in several cancer types. Nevertheless, the role of LINC01194 in lung adenocarcinoma (LUAD) has not yet been revealed.

Methods

qRT-PCR was used to detect the expression of LINC01194, miR-641 and SETD7 mRNA, while western blot was exploited to examine SETD7 protein level. Cell proliferation was detected by colony formation and EdU assays. Transwell assays detected cell migration and invasion. TUNEL assay and flow cytometry analysis were used to detect cell apoptosis. RIP, RNA pull down and luciferase reporter assays detected the binding among LINC01194, miR-641 and SETD7.

Results

LINC01194 was significantly upregulated in LUAD tissues and cell lines. Knockdown of LINC01194 resulted in decreased cell proliferation, migration and invasion, and increased apoptosis. Mechanistic experiments unveiled that LINC01194 augmented SETD7 expression in LUAD cells by competitively interacting with miR-641. Rescue experiments showed that miR-641 inhibition and SETD7 overexpression rescued the repressing impacts on LUAD cell proliferation, migration and invasion caused by LINC01194 knockdown.

Conclusion

LINC01194 promotes the progression of LUAD by enhancing miR-641-targeted SETD7. The LINC01194/miR-641/SETD7 axis might provide new molecular targets for treating LUAD.

Small RNAs, Big Diseases

The past two decades have seen extensive research done to pinpoint the role of microRNAs (miRNAs) that have led to discovering thousands of miRNAs in humans. It is not, therefore, surprising to see many of them implicated in a number of common as well as rare human diseases. In this review article, we summarize the progress in our understanding of miRNA-related research in conjunction with different types of cancers and neurodegenerative diseases, as well as their potential in generating more reliable diagnostic and therapeutic approaches.

Circular RNA S-7 promotes ovarian cancer EMT via sponging miR-641 to up-regulate ZEB1 and MDM2

BACKGROUND

Ovarian cancer (OC) is one lethal gynecologic cancer, with a 5-year survival rate approximately 47% and localized stage diagnosis of 15%. Circular RNAs are promising biomarkers for malignancies.

METHODS

CiRS-7 expression was confirmed in 40 paired OC and normal adjacent tissues from 40 OC patients with different TNM stages, lymph node metastasis status and overall survival rate, also 5 different OC cell lines by qRT-PCR. Effects of ciRS-7 silence on OC cell phenotypes were determined in OC cells and Xenograft mouse model. StarBase was used to predict binding sites between ciRS-7 and micRNAs. Pearson correlation analysis and RNA-immunoprecipitation assay were used to determine the association between genes. Point mutation and rescue experiments were applied for molecular mechanism investigation.

RESULTS

CiRS-7 expression was significantly higher in OC cells and tissues, which was significantly associated with the TNM stages, lymph node metastasis status and overall survival rate in OC patients. CiRS-7 silence inhibited OC cell growth and metastasis. CiRS-7 sponged miR-641 to up-regulate ZEB1 and MDM2 expression in OC development.

CONCLUSION

CiRS-7 serves as a competing endogenous RNA of miR-641 that promoted cell growth and metastasis in OC, via regulating ZEB1 and MDM2-mediated EMT. High ciRS-7 expression was a poor prognosis of TNM stages, lymph node metastasis status and overall survival rate in OC patients. Targeting ciRS-7/miR-641/ZEB1 or ciRS-7/miR-641/MDM2 axis may be a novel diagnostic, prognostic and therapeutic strategy for OC.

Circular RNA CDR1as Exerts Oncogenic Properties Partially through Regulating MicroRNA 641 in Cholangiocarcinoma

It has been found that the circular RNA (circRNA) CDR1as is upregulated in cholangiocarcinoma (CCA) tissues. In this study, we tried to explore the roles of CDR1as in CCA. CDR1as was overexpressed or knocked down in human CCA cells to assess the effects of CDR1as on cell behaviors and tumor xenograft growth. In vitro, the CDR1as level was significantly increased in CCA cell lines. The results showed that CDR1as promoted the cell proliferation, migration, invasion, and activation of the AKT3/mTOR pathway in CCA cells. Moreover, miR-641, a predicted target microRNA (miRNA) of CDR1as, could partially reverse the effects of CDR1as on cell behaviors in CCA cells. Furthermore, CDR1as improved tumor xenograft growth, and it could be attenuated by miR-641 in vivo Additionally, CDR1as expression was inversely correlated with miR-641 in CCA cells, and miR-641 could directly bind with CDR1as and its target genes, the AKT3 and mTOR genes. Mechanistically, CDR1as could bind with miR-641 and accelerate miR-641 degradation, which possibly leads to the upregulation of the relative mRNA levels of AKT3 and mTOR in RBE cells. In conclusion, our findings indicated that CDR1as might exert oncogenic properties, at least partially, by regulating miR-641 in CCA. CDR1as and miR-641 could be considered therapeutic targets for CCA.

CircRNA CDR1as/miR-641/HOXA9 pathway regulated stemness contributes to cisplatin resistance in non-small cell lung cancer (NSCLC)

Background

Cisplatin (DDP) is the first-line chemotherapeutic drug for non-small cell lung cancer (NSCLC), and long-term DDP stimulation increased resistance of NSCLC cells to this drug by enriching cancer stem cells (CSCs), which contributed to recurrence and worse prognosis of NSCLC, but the molecular mechanisms are still not fully delineated.

Methods

Real-Time qPCR and Western Blot analysis were conducted to examine gene expressions at mRNA and protein levels, respectively. Dual-luciferase reporter gene system was used to validate the targeting sites among circRNA CDR1as, miR-641 and HOXA9 mRNA. Cell growth was evaluated by CCK-8 assay, trypan blue staining assay and colony formation assay. The Annexin V-FITC/PI double staining method was employed to measure cell apoptosis ratio. Spheroid formation and flow cytometer assay was used to evaluate cell stemness. Xenograft mice models were established to measure tumorgenicity in vivo, and Ki67 expressions in mice tumor tissues were examined by immunohistochemistry (IHC).

Results

Here we identified a novel circRNA CDR1as/miR-641/Homeobox protein Hox-A9 (HOXA9) pathway regulated stemness and DDP chemoresistance in NSCLC. Mechanistically, circRNA CDR1as and HOXA9 were high-expressed, while miR-641 was low-expressed in DDP-resistant NSCLC cells, instead of their corresponding parental DDP-sensitive NSCLC cells. Additionally, we validated that circRNA CDR1as positively regulated HOXA9 in NSCLC cells by serving as an RNA sponge for miR-641, and knock-down of circRNA CDR1as increased the sensitivity of DDP-resistant NSCLC cells, which were reversed by downregulating miR-641 and upregulating HOXA9. Consistently, overexpression of circRNA CDR1as increased drug resistance of DDP-sensitive NSCLC cells by regulating miR-641/HOXA9 axis. In addition, the expression levels of stemness signatures (SOX2, OCT4 and Nanog) were higher in DDP-resistant NSCLC cells, which also tended to form spheres and enrich CD44⁺CD166⁺ population compared to their parental DDP-sensitive NSCLC cells, suggesting that CSCs were enriched in DDP-resistant NSCLC cells. Notably, knock-down of circRNA CDR1as inhibited stemness of DDP-resistant NSCLC cells by inhibiting HOXA9 through upregulating miR-641.

Conclusions

Taken together, this study identified that circRNA CDR1as regulated stemness and DDP chemoresistance in NSCLC cells by targeting miR-641/HOXA9 axis.

Circular RNA circUBAP2 regulates proliferation and invasion of osteosarcoma cells through miR-641/YAP1 axis

Background

Osteosarcoma (OS) is a common malignant bone cancer and is still a growing threat to young people. Circular RNAs (CircRNAs) are reported to be involved in the development of diverse human cancers. However, the role of circUBAP2 in OS progression is rarely reported.

Methods

Quantitative real-time polymerase chain reaction (qRT-PCR) was conducted to detect the expression levels of circUBAP2 and miR-641 in OS tissues and cells. Cell Counting Kit-8 (CCK-8) assay was employed to check cell proliferation. The ability of cell invasion was evaluated by transwell assay. The protein levels of E-cadherin, Vimentin and Yes-associated protein 1 (YAP1) were measured by western blot. The starBase was used to predict binding sites between miR-641 and circUBAP2 or YAP1 and the dual-luciferase reporter assay was performed to verify the interaction.

Results

The level of circUBAP2 was significantly upregulated in OS tissues and cells compared with normal tissues and cells, which was contrary to the expression of miR-641. Downregulation of circUBAP2 suppressed proliferation and invasion of OS cells and weakened the process of epithelial-mesenchymal transition (EMT). Moreover, miR-641 was a target of circUBAP2 and could bind to the 3′-untranslated region (3′UTR) of YAP1. In addition, overexpression of circUBAP2 or YAP1 reversed the inhibitory effects of miR-641 on proliferation and invasion of OS cells. Further research indicated that circUBAP2 regulated the expression of YAP1 by interacting with miR-641 in OS cells.

Conclusion

Knockdown of circUBAP2 impeded proliferation and invasion of OS cells by downregulating the expression of YAP1 via sponging miR-641.

Global Analysis of miRNA Signature Differentially Expressed in Insulin-resistant Human Hepatocellular Carcinoma Cell Line

Chemoresistance mediated by insulin resistance (IR) in HCC has already been validated. However, the underlying mechanism, especially the involvement of microRNAs (miRNAs) was unelucidated. In this study, miRNA microarrays and bioinformatics methods were employed to determine the dysregulation of miRNA by IR in HCC cells, and quantitative RT-PCR (qRT-PCR) was applied to valid the miRNA array data. Of all the 2006 miRNAs screened, 32 miRNAs were found up or down regulated between the HepG2/IR cells and its parental cells. Further literature mining revealed that some of these miRNAs may function as oncogenes or tumor suppressors that contribute to tumor progression, recurrence, and metastasis which eventually lead to chemotherapeutic resistance. Interestingly, bioinformatics analysis by Gene Ontology (GO) enrichment pathway indicating that function of the predicted target genes of these dysregulated miRNAs were significantly enriched in the processes related with biosynthesis, catabolism, modification etc., and Kyoto Encyclopedia of Genes and Genomes (KEGG) mapping showed that the biological regulatory mechanisms were integrated in cancer-related pathways. Moreover, we also constructed a network which connected the differentially expressed miRNAs to target genes, GO enrichments and KEGG pathways to reveal the hub miRNAs, genes and pathways. Collectively, our present study demonstrated the possible miRNAs and predicted target genes involving in the pathophysiology of insulin resistant HCC, providing novel insights into the molecular mechanisms of multidrug resistance in the insulin resistant HepG2 cells.

Noncoding RNAs and Liquid Biopsy in Lung Cancer: A Literature Review

Lung cancer represents a genetically heterogeneous disease with low survival rates. Recent data have evidenced key roles of noncoding RNAs in lung cancer initiation and progression. These functional RNA molecules that can act as both oncogenes and tumor suppressors may become future biomarkers and more efficient therapeutic targets. In the precision medicine era, circulating nucleic acids have the potential to reshape the management and prognosis of cancer patients. Detecting genomic alterations and level variations of circulating nucleic acids in liquid biopsy samples represents a noninvasive method for portraying tumor burden. Research is currently trying to validate the potential role of liquid biopsy in lung cancer screening, prognosis, monitoring of disease progression, and treatment response. However, this method requires complex detection assays, and implementation of plasma genotyping in clinical practice continues to be hindered by discrepancies that arise when compared to tissue genotyping. Understanding the genomic landscape of lung cancer is essential in order to provide useful and innovative research in the age of patient-tailored therapy. In this landscape, the noncoding RNAs play a crucial role due to their target genes that dramatically influence the tumor microenvironment and the response to therapy. This article addresses present and future possible roles of liquid biopsy in lung cancer. It also discusses how the complex role of noncoding RNAs in lung tumorigenesis could influence the management of this pathology.

miR-1305 Inhibits The Progression Of Non-Small Cell Lung Cancer By Regulating MDM2

Background

Increasing evidence has suggested the critical implication of microRNAs (miRNAs) in the initiation and progression of non-small cell lung cancer (NSCLC). Previous studies have shown the tumor-suppressive function of miR-1305 in cancer; however, the role of miR-1305 in NSCLC has not been fully understood.

Methods

The expression of miR-1305 in NSCLC was detected by RT-qPCR. The influence of miR-1305 on the growth of NSCLC cells was determined via Cell Counting Kit 8 (CCK-8), colony formation and FACS analysis. The targets of miR-1305 were predicted with the miRDB database. Luciferase reporter assay was performed to investigate the binding between miR-1305 and 3ʹ-UTR of MDM2. Western blot was applied to check the expression of MDM2 with miR-1305.

Results

Here, we found that miR-1305 was down-regulated in NSCLC tissues and cell lines. Decreased miR-1305 was significantly correlated with the metastasis and poor prognostics of NSCLC patients. Overexpression of miR-1305 inhibited the proliferation and migration and promoted the apoptosis of NSCLC cells. Bioinformatics and luciferase assay uncovered that the mouse/murine double minute 2 (MDM2) was a target of miR-1305. miR-1305 bound the 3ʹ-untranslated region (UTR) of MDM2 and decreased the expression of MDM2 in NSCLC cells. As MDM2 was a negative regulator of p53, decreased MDM2 by miR-1305 up-regulated the abundance of p53 in NSCLC cells. Restoration of MDM2 markedly attenuated the suppressive role of miR-1305 in the proliferation and migration of NSCLC cells.

Conclusion

The findings provided novel mechanism of miR-1305/MDM2 signaling in regulating the progression of NSCLC, suggesting miR-1305 as a promising target for the treatment of NSCLC.

[A review on muscle-specific microRNAs as the biomarker for Duchenne muscular dystrophy]

MicroRNA (miRNA) is a non-coding single-stranded RNA with a length of approximately 22 nucleotides and is mainly responsible for the regulation of gene expression at the post-transcriptional level. At present, miRNA have become potential biomarkers for various diseases such as tumor, leukemia, and nervous system disease. Muscle-specific microRNAs are enriched in the skeletal muscle of patients with Duchenne muscular dystrophy (DMD) and also play an important role in the pathogenesis of DMD. Creatine kinase has limited specificity in the diagnosis of DMD since its level is not significantly associated with disease severity, and therefore, it is of great clinical significance to explore whether muscle-specific microRNAs can be used as ideal biomarkers for DMD. This article reviews the research advances in this field.

[A review on muscle-specific microRNAs as the biomarker for Duchenne muscular dystrophy]

MicroRNA (miRNA) is a non-coding single-stranded RNA with a length of approximately 22 nucleotides and is mainly responsible for the regulation of gene expression at the post-transcriptional level. At present, miRNA have become potential biomarkers for various diseases such as tumor, leukemia, and nervous system disease. Muscle-specific microRNAs are enriched in the skeletal muscle of patients with Duchenne muscular dystrophy (DMD) and also play an important role in the pathogenesis of DMD. Creatine kinase has limited specificity in the diagnosis of DMD since its level is not significantly associated with disease severity, and therefore, it is of great clinical significance to explore whether muscle-specific microRNAs can be used as ideal biomarkers for DMD. This article reviews the research advances in this field.

MicroRNAs in cancer cell death pathways: Apoptosis and necroptosis

To protect tissues and the organism from disease, potentially harmful cells are removed through programmed cell death processes, including apoptosis and necroptosis. These types of cell death are critically controlled by microRNAs (miRNAs). MiRNAs are short RNA molecules that target and inhibit expression of many cellular regulators, including those controlling programmed cell death via the intrinsic (Bcl-2 and Mcl-1), extrinsic (TRAIL and Fas), p53-and endoplasmic reticulum (ER) stress-induced apoptotic pathways, as well as the necroptosis cell death pathway. In this review, we discuss the current knowledge of apoptosis and necroptosis pathways and how these are impaired in cancer cells. We focus on how miRNAs disrupt apoptosis and necroptosis, thereby critically contributing to malignancy. Understanding which and how miRNAs and their targets affect cell death pathways could open up novel therapeutic opportunities for cancer patients. Indeed, restoration of pro-apoptotic tumor suppressor miRNAs (apoptomiRs) or inhibition of oncogenic miRNAs (oncomiRs) represent strategies that are currently being trialed or are already applied as miRNA-based cancer therapies. Therefore, better understanding the cancer type-specific expression of apoptomiRs and oncomiRs and their underlying mechanisms in cell death pathways will not only advance our knowledge, but also continue to provide new opportunities to treat cancer.

lncRNA Colorectal Neoplasia Differentially Expressed (CRNDE) Promotes Proliferation and Inhibits Apoptosis in Non-Small Cell Lung Cancer Cells by Regulating the miR-641/CDK6 Axis

BACKGROUND The lncRNA Colorectal Neoplasia Differentially Expressed (CRNDE) gene has been reported as a potential oncogene in NSCLC. Nevertheless, the molecular mechanism of CRNDE in NSCLC progression remains largely unknown. MATERIAL AND METHODS qRT-PCR assay was performed to detect the expression levels of CRNDE, miR-641, and cyclin-dependent kinase 6 (CDK6) in NSCLC. Western blot assay was employed to assess CDK6 protein level in treated NSCLC cells. si-CRNDE#1, si-CRNDE#2, miR-641 mimics, miR-641 inhibitors, or Vector-CDK6 were transfected into NSCLC cells to change the expression levels of CRNDE, miR-641, or CDK6. Dual-luciferase reporter assay was performed to validate the direct interrelated miRNA of CRNDE and the potential target of miR-641. MTT and flow cytometry assays were performed to assess the capacities of cell proliferation and apoptosis, respectively. RESULTS CRNDE level was upregulated in NSCLC, and its knockdown suppressed NSCLC cells proliferation and enhanced apoptosis, whereas miR-641 antagonized the regulatory effect of CRNDE knockdown by directly binding to CRNDE. Moreover, CDK6 was a target of miR-641 and miR-641 exerted anti-proliferation and pro-apoptosis effects through CDK6. CONCLUSIONS CRNDE promoted proliferation and inhibited apoptosis of NSCLC cells at least in part by regulating the miR-641/CDK6 axis, suggesting that CRNDE is a potential therapeutic target for NSCLC treatment.

The Roles of MicroRNA in Lung Cancer

Lung cancer is the most devastating malignancy in the world. Beyond genetic research, epigenomic studies—especially investigations of microRNAs—have grown rapidly in quantity and quality in the past decade. This has enriched our understanding about basic cancer biology and lit up the opportunities for potential therapeutic development. In this review, we summarize the involvement of microRNAs in lung cancer carcinogenesis and behavior, by illustrating the relationship to each cancer hallmark capability, and in addition, we briefly describe the clinical applications of microRNAs in lung cancer diagnosis and prognosis. Finally, we discuss the potential therapeutic use of microRNAs in lung cancer.

miRNA-641 inhibits the proliferation, migration, and invasion and induces apoptosis of cervical cancer cells by directly targeting ZEB1

Background

miRNAs have been found to be dysregulated in cervical cancer. The dysregulation of miRNA has been implicated in cervical carcinogenesis and progression. Therefore, further studies of the specific roles of deregulated miRNAs in cervical cancer and underlying molecular mechanisms may facilitate the identification of novel therapeutic techniques for patients with this disease. miRNA-641 (miR-641) was previously reported to serve an important role in lung cancer. However, the expression pattern and roles of miR-641 in cervical cancer remain unclear.

Method

In this study, the expression level of miR-641 in cervical cancer tissues and cell lines was detected using RT-qPCR. The influence of miR-641 upregulation in cervical cancer cell proliferation, apoptosis, migration and invasion was evaluated using CCK-8 assay, flow cytometry assay, migration and invasion assays, respectively. In vivo tumor growth assay was utilized to determine the effect of miR-641 overexpression in the tumor growth of cervical cancer cells in vivo. The molecular mechanisms underlying the action of miR-641 in cervical cancer cells were also explored.

Results

We found that miR-641 expression was obviously decreased in cervical cancer tissues and cell lines, which strongly correlated with the International Federation of Gynecology and Obstetrics stage and lymph node metastasis. Upregulation of miR-641 inhibited cell proliferation, induced apoptosis, and reduced metastasis in cervical cancer. Additionally, bioinformatics analysis predicted ZEB1 as a novel target gene of miR-641. Notably, luciferase reporter assay, RT-qPCR, and Western blot analysis revealed that miR-641 decreased ZEB1 expression in cervical cancer cells by directly targeting its 3'-untranslated region. Furthermore, ZEB1 was upregulated in cervical cancer tissues, which was negatively correlated with miR-641 expression. Moreover, recovered ZEB1 expression attenuated the tumor suppressive action of miR-641 overexpression in the malignant phenotypes of cervical cancer cells. Besides, miR-641 could hinder cervical cancer tumor growth in vivo by inhibiting ZEB1.

Conclusion

These results indicate that miR-641 has tumor suppressive roles in the development of cervical cancer by directly targeting ZEB1, suggesting that miR-641 is a novel, effective therapeutic target for treating patients with this disease.