miR-497-5p inhibits cell proliferation and invasion by targeting KCa3.1 in angiosarcoma

Genomic landscape and preclinical models of angiosarcoma

Angiosarcoma is a cancer that develops in blood or lymphatic vessels that presents a significant clinical challenge due to its rarity and aggressive features. Clinical outcomes have not improved in decades, highlighting a need for innovative therapeutic strategies to treat the disease. Genetically, angiosarcomas exhibit high heterogeneity and complexity with many recurrent mutations. However, recent studies have identified some common features within anatomic and molecular subgroups. To identify potential therapeutic vulnerabilities, it is essential to understand and integrate the mutational landscape of angiosarcoma with the models that exist to study the disease. In this review, we will summarize the insights gained from reported genomic alterations in molecular and anatomic subtypes of angiosarcoma, discuss several potential actionable targets, and highlight the preclinical disease models available in the field.

Novel Detection and Clinical Utility of Serum-Derived Extracellular Vesicle in Angiosarcoma

Cutaneous angiosarcoma is a rare and highly aggressive skin malignancy. The aim of this study is to explore the alteration of serum-derived extracellular vesicle (EV) in angiosarcoma patients and to evaluate its clinical utility as a novel circulating biomarker. In a microarray analysis to examine the differential expression of specific EV-associated microRNAs in sera between cutaneous angiosarcoma patients and healthy controls, 73 microRNAs with significant upregulation and 100 microRNAs with significant downregulation, respectively, were identified in patients with angio-sarcoma. Among them, quantitative PCR confirmed that miR-184, miR-3925-5p, miR-3926, and miR-5703 were upregulated in sera of cutaneous angiosarcoma patients compared with those of healthy controls and melanoma patients. Additionally, these 4 microRNAs were expressed more highly in angiosarcoma cell lines compared with normal human endothelial cell lines and were prone to elevate along with disease progression. Furthermore, a gene analysis predicted that the target gene set of microRNAs might affect the regulation of TP53 via the epigenetic regulation of MECP2. Taken together, these 4 extracellular vesicle-associated microRNAs in circulation serve as a promising liquid biomarker to identify angiosarcoma patients and trace disease progression.

CRISPR detection of cardiac tumor-associated microRNAs

As multiple imaging modalities cannot reliably diagnose cardiac tumors, the molecular approach offers alternative ways to detect rare ones. One such molecular approach is CRISPR-based diagnostics (CRISPR-Dx). CRISPR-Dx enables visual readout, portable diagnostics, and rapid and multiplex detection of nucleic acids such as microRNA (miRNA). Dysregulation of miRNA expressions has been associated with cardiac tumors such as atrial myxoma and angiosarcoma. Diverse CRISPR-Dx systems have been developed to detect miRNA in recent years. These CRISPR-Dx systems are generally classified into four classes, depending on the Cas proteins used (Cas9, Cas12, Cas13, or Cas12f). CRISPR/Cas systems are integrated with various isothermal amplifications to detect low-abundance miRNAs. Amplification-free CRISPR-Dx systems have also been recently developed to detect miRNA directly. Herein, we critically discuss the advances, pitfalls, and future perspectives for these CRISPR-Dx systems in detecting miRNA, focusing on the diagnosis and prognosis of cardiac tumors.

Intermediate conductance calcium-activated potassium channel (KCa3.1) in cancer: Emerging roles and therapeutic potentials

The KCa3.1 channel (also known as the KCNN4, IK1, or SK4 channel) is an intermediate-conductance calcium-activated potassium channel that regulates the membrane potential and maintains calcium homeostasis. Recently, KCa3.1 channels have attracted increasing attention because of their diverse roles in various types of cancers. In cancer cells, KCa3.1 channels regulate key processes, including cell proliferation, cell cycle, migration, invasion, tumor microenvironments, and therapy resistance. In addition, abnormal KCa3.1 expression in cancers is utilized to distinguish between tumor and normal tissues, classify cancer stages, and predict patient survival outcomes. This review comprehensively examines the current understanding of the contribution of KCa3.1 channels to tumor formation, metastasis, and its mechanisms. We evaluated the potential of KCa3.1 as a biomarker for cancer diagnosis and prognosis. Finally, we discuss the advances and challenges of applying KCa3.1 modulators in cancer treatment and propose approaches to overcome these obstacles. In summary, this review highlights the importance of this ion channel as a potent therapeutic target and prognostic biomarker of cancer.

Dysregulation of miRNAs in Soft Tissue Sarcomas

MicroRNAs (miRNAs) are pivotal regulators of gene expression, influencing key cellular processes such as proliferation, differentiation, apoptosis, and metastasis. In the realm of sarcomas-a diverse group of malignant tumors affecting soft tissues and bone sarcomas-miRNAs have emerged as crucial players in tumorigenesis and tumor progression. This review delves into the intricate roles of miRNAs across various soft tissue sarcoma subtypes, including rhabdomyosarcoma, liposarcoma, leiomyosarcoma, synovial sarcoma, fibrosarcoma, angiosarcoma, undifferentiated pleomorphic sarcoma (UPS), and malignant peripheral nerve sheath tumor (MPNST). We explore how dysregulated miRNAs function as oncogenes or tumor suppressors, modulating critical pathways that define the aggressive nature of these cancers. Furthermore, we discuss the diagnostic and prognostic potential of specific miRNAs and highlight their promise as therapeutic targets. By understanding the miRNA-mediated regulatory networks, this review aims to provide a comprehensive overview of current research while pointing towards future directions for miRNA-based therapies. Our findings underscore the potential of miRNAs to transform the landscape of sarcoma treatment, offering hope for more precise, personalized, and effective therapeutic strategies.

miR-497 Target Gene Regulatory Network in Angiosarcoma

Angiosarcoma is a vascular sarcoma that is highly aggressive and metastatic. Because of its rarity, treatment options for patients are limited. Therefore, more research is needed to identify possible therapeutic vulnerabilities. We previously found that conditional deletion of Dicer1 drives angiosarcoma development in mice. Given the role of DICER1 in canonical miRNA biogenesis, this suggests that miRNA loss is important in angiosarcoma development. After testing miRNAs previously suggested to have a tumor-suppressive role in angiosarcoma, miRNA-497-5p (miR-497) suppressed cell viability most significantly. We also found that miR-497 overexpression led to significantly reduced cell migration and tumor formation. To understand the mechanism of miR-497 in tumor suppression, we identified clinically relevant target genes using a combination of RNA-sequencing data in an angiosarcoma cell line, expression data from patients with angiosarcoma, and target prediction algorithms. We validated miR-497 direct regulation of cyclin-D2, cyclin-dependent kinase 6, and vesicle amine transport protein 1 (VAT1). One of these genes, VAT1, is an understudied protein that has been suggested to promote cell migration and metastasis in other cancers. Indeed, we find that pharmacologic inhibition of VAT1 with the natural product neocarzilin A reduces angiosarcoma migration. Implications: This work supports the potent tumor-suppressive abilities of miR-497 in angiosarcoma, providing evidence for its potential as a therapeutic agent, and provides insight into the mechanisms of tumor suppression through analysis of the target gene regulatory network of miR-497.

miR-497-5p Expression and Biological Activity in Gastric Cancer

Background: This research aims to investigate the expression and biological roles of miR-497-5p in gastric cancer (GC), and its possible mechanisms. Methods: Real Time Quantitative PCR (RT-qPCR) was performed to detect miR-497-5p in GC and normal tissues, as well as GC cell lines versus normal gastric mucosal cells (GES-1). The effects of miR-497-5p overexpression on proliferation were measured by the cell counting kit-8 (CCK8) assay and ethidium bromide (EdU) assay. Flow cytometry was used to assess the cell cycle. The migration and invasion were evaluated by scratch assay and Transwell assay, respectively. Gene targets of miR-497-5p were predicted using "multiMiR" R package combined with mirTarPathway database. And then luciferase reporter experiment was used to evaluate the activity of ERBB2 by miR-497-5p mimics in GC cell line. Besides, functional experiments were performed to verify the impact of miR-497-5p /ERBB2 on phenotypes of GC cells. Results: Compared with the normal tissues and mucosal cells, miR-497-5p was reduced in GC tissues and GC cell lines. miR-497-5p significantly decreased proliferation, migration, and invasion capacity, with an elevated apoptosis ratio of gastric cancer cells. Bioinformatics indicated that ERBB2 might be the potential target of miR-497-5p Dual-luciferase reporter experiments showed it adversely regulated ERBB2 3'UTR luciferase activity. The expression of ERBB2 in GC tissues and cells is significantly higher compared to normal tissues and cells. Over-expression of ERBB2 in gastric cancer cells significantly reduced miR-497-5p's inhibitory effect on the malignant behavior of GC cells. Conclusion: miR-497-5p was significantly down-regulated in GC tissues and cells, which inhibited the malignant features of GC cells by targeting ERBB2.

Current understanding of comparative pathology and prospective research approaches for canine hemangiosarcoma

Hemangiosarcoma (HSA) is a malignant tumor originating from endothelial cells. HSA typically develops in dogs, but is rare in other animals, including humans. Although surgery and chemotherapy are conventional treatments for HSA, neither treatment can significantly improve patient prognosis. To develop novel and effective therapeutics, a deeper understanding of HSA pathogenesis must be acquired. However, the limited research tools for HSA have been unable to make a breakthrough; therefore, it is crucial to widely utilize or establish novel research tools such as patient-derived xenograft models, organoids, and chicken embryo xenograft models. The pathogenesis of the human counterpart of HSA, angiosarcoma (AS), also remains incompletely understood, preventing the extrapolation of findings from humans to dogs, unlike other diseases. In this review, we summarize the clinicopathological and morphological features of HSA, and then we discuss the current understanding of the molecular pathology of HSA. Finally, we highlight promising research tools that may accelerate HSA basic research toward developing novel therapeutics. We also briefly summarize AS to help researchers comprehend HSA from the perspective of comparative pathology.

Target gene regulatory network of miR-497 in angiosarcoma

Angiosarcoma (AS) is a vascular sarcoma that is highly aggressive and metastatic. Due to its rarity, treatment options for patients are limited, therefore more research is needed to identify possible therapeutic vulnerabilities. We previously found that conditional deletion of Dicer1 drives AS development in mice. Given the role of DICER1 in canonical microRNA (miRNA) biogenesis, this suggests that miRNA loss is important in AS development. After testing miRNAs previously suggested to have a tumor-suppressive role in AS, microRNA-497-5p (miR-497) suppressed cell viability most significantly. We also found that miR-497 overexpression led to significantly reduced cell migration and tumor formation. To understand the mechanism of miR-497 in tumor suppression, we identified clinically relevant target genes using a combination of RNA-sequencing data in an AS cell line, expression data from AS patients, and target prediction algorithms. We validated miR-497 direct regulation of CCND2, CDK6, and VAT1. One of these genes, VAT1, is an understudied protein that has been suggested to promote cell migration and metastasis in other cancers. Indeed, we find that pharmacologic inhibition of VAT1 with the natural product Neocarzilin A reduces AS migration. This work provides insight into the mechanisms of miR-497 and its target genes in AS pathogenesis.

Small Non-Coding RNAs in Soft-Tissue Sarcomas: State of the Art and Future Directions

Soft-tissue sarcomas (STS) are a rare and heterogeneous group of tumors that arise from connective tissue and can occur anywhere in the body. Among the plethora of over 50 different STS types, liposarcoma (LPS) is one of the most common. The subtypes of STS are characterized by distinct differences in tumor biology that drive responses to pharmacologic therapy and disparate oncologic outcomes. Small non-coding RNAs (sncRNA) are a heterogeneous class of regulatory RNAs involved in the regulation of gene expression by targeting mRNAs. Among the several types of sncRNAs, miRNAs and tRNA-derived ncRNAs are the most studied in the context of tumor biology, and we are learning more about the role of these molecules as important regulators of STS tumorigenesis and differentiation. However, challenges remain in translating these findings and no biomarkers or therapeutic approaches targeting sncRNAs have been developed for clinical use. In this review, we summarize the current landscape of sncRNAs in the context of STS with an emphasis on LPS, including the role of sncRNAs in the tumorigenesis and differentiation of these rare malignancies and their potential as novel biomarkers and therapeutic targets. Finally, we provide an appraisal of published studies and outline future directions to study sncRNAs in STS, including tRNA-derived ncRNAs.

Role of organellar Ca2+-activated K+ channels in disease development

The organellar Ca2+-activated K+ channels share a similar ability to transfer the alteration of Ca2+ concentration to membrane conductance of potassium. Multiple effects of Ca2+-activated K+ channels on cell metabolism and complex signaling pathways during organ development have been explored. The organellar Ca2+-activated K+ channels are able to control the ionic equilibrium and are always associated with oxidative stress in different organelles and the whole cells. Some drugs targeting Ca2+-activated K+ channels have been tested for various diseases in clinical trials. In this review, the known roles of organellar Ca2+-activated K+ channels were described, and their effects on different diseases, particularly on diabetes, cardiovascular diseases, and neurological diseases were discussed. It was attempted to summarize the currently known operational modes with the involvement of organellar Ca2+-activated K+ channels. This review may assist scholars to more comprehensively understand organellar Ca2+-activated K+ channels and related diseases.

MicroRNAs in the Pathogenesis, Prognostication and Prediction of Treatment Resistance in Soft Tissue Sarcomas

Soft tissue sarcomas are highly aggressive malignant neoplasms of mesenchymal origin, accounting for less than 1% of adult cancers, but comprising over 20% of paediatric solid tumours. In locally advanced, unresectable, or metastatic disease, outcomes from even the first line of systemic treatment are invariably poor. MicroRNAs (miRNAs), which are short non-coding RNA molecules, target and modulate multiple dysregulated target genes and/or signalling pathways within cancer cells. Accordingly, miRNAs demonstrate great promise for their utility in diagnosing, prognosticating and improving treatment for soft tissue sarcomas. This review aims to provide an updated discussion on the known roles of specific miRNAs in the pathogenesis of sarcomas, and their potential use in prognosticating outcomes and prediction of therapeutic resistance.

MEG8：An Indispensable Long Non-coding RNA in Multiple Cancers

BACKGROUND

As a member of long non-coding RNAs (lncRNAs), maternally expressed gene 8 (MEG8) has been found involving in the progression of a variety of cancers and playing a regulatory role. Therefore, MEG8 may turn into a new therapeutic target for cancer in the future. The purpose of this review is to illustrate the molecular mechanism and physiological function of MEG8 in various cancers.

METHODS

We retrieved and analyzed related articles about MEG8, lncRNAs and cancers, and then summarize the pathophysiological mechanisms of MEG8 in cancer development.

RESULTS

LncRNA MEG8 participates in various cancers progression, thus influencing the proliferation, migration, and invasion of cancers. However, the expression of MEG8 is abnormally upregulated in non-small cell lung cancer (NSCLC), pancreatic cancer (PC), liver cancer (HCC), pituitary adenoma (PA) and hemangioma (HA), and inhibited in colorectal cancer (CRC), ovarian cancer (OC) and giant cell tumor (GCT), suggesting its clinical value in cancer therapy.

CONCLUSIONS

LncRNA MEG8 is expected to be a new therapeutic target or biomarker for a wide range of cancers in the future.

Differences in potential key genes and pathways between primary and radiation-associated angiosarcoma of the breast

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Angiosarcoma of the breast is a high-grade malignant soft tissue tumor, it can be divided into primary and secondary.

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The differences between primary and secondary angiosarcomas in terms of pathogenesis, clinical behavior, early diagnosis biomarkers, genetic abnormalities, and therapeutic targets remain to be fully elucidated.

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Due to its rarity, most of the current information relating to angiosarcoma is provided by case reports and single-institution retrospective cohort studies and the research with large-scale genomic studies published to date are very limited.

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We identified the differentially expressed genes (DEGs) between primary and second breast angiosarcomas and identified the hub genes as well as predicted novel biomarkers, pathways, and potential therapeutic targets for primary and secondary breast angiosarcomas.

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We aimed to identify novel biomarkers, pathways, and potential therapeutic targets for primary and secondary breast angiosarcomas to facilitate future research.

Background

Angiosarcoma of the breast is a high-grade malignant soft tissue tumor, it can be divided into primary and radiation-associated angiosarcoma(secondary). However, the differences between primary and secondary angiosarcomas in terms of pathogenesis, clinical behavior, early diagnosis biomarkers, genetic abnormalities, and therapeutic targets remain to be fully elucidated. At the same time, due to its rarity, most of current information relating to angiosarcoma is provided by case reports. Therefore, exploring the mechanisms of primary and secondary breast angiosarcoma have important value for the discovery of new biomarkers and research into potential therapeutic targets.

Methods

The differentially expressed genes (DEGs) between 36 cases of primary angiosarcoma and 54 cases of secondary angiosarcoma were screened. Then, the DEGs were used to gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Then, a protein-protein interaction (PPI) network was constructed using the STRING database.

Results

A total of 18 DEGs were identified, of which 13 were upregulated and 5 were downregulated in secondary breast angiosarcoma. The GO enrichment analysis showed that the DEGs were most enriched in metabolism, energy pathways, and protein metabolism in biological processes. The enriched signaling pathways of DEGs were the transforming growth factor-β (TGF-β), Wnt, Hippo and PI3K-Akt signaling pathways. Then, the PPI network was conducted and hub genes were identified and they were involved in thyroid hormone, Hippo and other signaling pathways.

Conclusion

This study lay the foundation for the discovery of effective and reliable molecular biomarkers and essential therapeutic targets for these malignancies.

Kutane Angiosarkome: molekulare Pathogenese und neue therapeutische Ansätze

Das kutane Angiosarkom (CAS) ist ein hochaggressiver maligner Tumor mit schlechter Prognose. Das primäre, spontane CAS (pCAS) und das sekundäre, mit einer Bestrahlung oder einem Lymphödem assoziierte CAS (sCAS) unterscheiden sich klinisch sowie molekular. Die Amplifikation/Überexpression von Myc ist ein charakteristisches, wenn auch nicht ausschließliches Merkmal von sCAS, während der Verlust von TP53 selektiv bei pCAS vorkommt. Detaillierte molekulare Analysen mit modernen Multi-Omics-Ansätzen haben gezeigt, dass sowohl pCAS als auch sCAS eine erhebliche molekulare Heterogenität aufweisen. Die betroffenen Gene und ihre molekularen Regulatoren sind mögliche therapeutische Zielstrukturen. Darüber hinaus kann das pCAS in Cluster mit hoher Mutationsrate und/oder ausgeprägten Entzündungssignaturen eingeteilt werden, die als Grundlage für die künftige Stratifizierung von pCAS-Patienten in immuntherapeutischen klinischen Studien dienen können. Während die Aufklärung der der Erkrankung zugrunde liegenden molekularen Veränderungen zügig voranschreitet, verläuft die Entwicklung daraus abgeleiteter neuer Therapien für das CAS jedoch bisher eher langsam. Dennoch wurden einige über die Standardtherapien wie Operation und Radiochemotherapie hinausgehende klinische Studien zu neuen Behandlungsmöglichkeiten initiiert. Dazu gehören zielgerichtete Therapien gegen VEGF und VEGFR1-3 wie Bevacizumab und Pazopanib, sowie β-Adrenozeptorenblocker wie Propranolol. Derzeit werden auch Immuntherapien entwickelt, unter anderem unter Verwendung der Immuncheckpoint-Inhibitoren Pembrolizumab und Nivolumab sowie des Anti-RANKL-Antikörper Denosumab.

Cutaneous Angiosarcomas: Molecular Pathogenesis Guides Novel Therapeutic Approaches

Cutaneous angiosarcoma (CAS) is a highly aggressive cancer with a poor prognosis. Primary, spontaneous CAS (pCAS) and secondary, post-irradiation- or lymphedema-associated CAS (sCAS) are clinically, but also molecularly distinct. Myc amplification/overexpression is a characteristic, although not exclusive feature of sCAS, while loss of TP53 selectively occurs in pCAS. Detailed molecular analyses with modern multi-omics approaches have revealed that both pCAS and sCAS exhibit considerable molecular heterogeneity. Affected genes and their molecular regulators including a plethora of microRNAs may serve as future drug targets. Furthermore, pCAS could be subdivided into clusters with high tumor mutational burden and/or high tumor inflammation signatures providing a rationale for the stratification of pCAS patients in future immunotherapeutic clinical studies. Development of novel treatment regimens guided by these molecular alterations, however, cannot fully keep up with the pace of their discovery due to the low incidence of the disease. Nevertheless, beyond conventional surgery and chemoradiotherapy, clinical trials investigating novel treatment options have been initiated including targeted therapies against VEGF and VEGFR1-3 such as bevacizumab and pazopanib, and β-adrenoreceptor blockers such as propranolol. Finally, immunotherapies are being developed including immune checkpoint inhibitors pembrolizumab and nivolumab as well as anti-RANKL antibody denosumab.

Establishment and characterization of two human cutaneous angiosarcoma cell lines, KU-CAS3 and KU-CAS5

BACKGROUND

Cutaneous angiosarcoma (CAS) is a rare but fatal cancer. Established CAS cell lines are necessary for the investigation of their properties and treatment options.

METHODS

Two cell lines, KU-CAS3 and KU-CAS5, were established from human angiosarcoma specimens obtained from the scalp. Flow cytometric assay, tube formation assay, low-density lipoprotein (LDL) uptake assay, immunofluorescence analysis, real-time PCR, tumorigenesis assay, and STR analysis were conducted.

RESULTS

The cells showed endothelial cell properties, based on the cobblestone appearance upon reaching confluence, CD31 positivity, tube-formation activity, active uptake of acetylated LDL, and vWF expression. The two cell lines expressed relatively high levels of adrenergic β2 receptor, and the VEGF1 and VEGF2 receptors. In the in vivo study, the growing neoplasms, confirmed as CAS, were identified as subcutaneous dark papules. KU-CAS cell lines were considered authentic based on STR profiling.

CONCLUSIONS

KU-CAS3 and KU-CAS5 are the first human CAS cell lines having tumorigenic potential in vivo.

Identification of serum microRNAs with differential expression between dogs with splenic masses and healthy dogs with histologically normal spleens

OBJECTIVE

To identify differential microRNA (miRNA) expression in dogs with splenic hemangiosarcoma, splenic hematoma, and histologically normal spleens.

ANIMALS

Dogs with splenic hemangiosarcoma (n = 10), splenic hematoma (n = 5), and histologically normal spleens (n = 5).

PROCEDURES

Splenic tissue and serum samples were collected from dogs with splenic masses (ie, hemangiosarcoma or hematoma samples) and healthy control dogs (ie, control samples), and total RNA was extracted. Reverse transcription quantitative real-time PCR was performed with 28 miRNAs associated with hemangiosarcoma, angiosarcoma, or associated genes. Differential expression analysis was performed.

RESULTS

Control tissue and serum samples had similar miRNA expression patterns, and hemangiosarcoma tissue and serum samples did not. Hemangiosarcoma serum samples had higher expression than hemangiosarcoma tissue for 13 miRNAs and lower expression for 1 miRNA. Control tissue and hemangiosarcoma tissue had varying expressions for 12 miRNAs, with 10 more highly expressed in control samples and 2 more highly expressed in hemangiosarcoma samples. Five miRNAs (miR-214-3p, miR-452, miR-494-3p, miR-497-5p, miR-543) had significantly different expression in serum between dogs with splenic masses (ie, hemangiosarcoma or hematoma) and serum of dogs with histologically normal spleens, with higher expression in the serum of dogs with splenic masses for all 5 miRNAs.

CONCLUSIONS AND CLINICAL RELEVANCE

5 circulating miRNAs were identified that distinguished dogs with splenic hemangiosarcoma or hematoma from those with histologically normal spleens. These 5 miRNAs had higher expression in dogs with splenic masses, indicating upregulation of these circulating miRNAs occurs in these splenic disease states. These miRNAs may be useful as a noninvasive screening tool that uses serum to identify dogs with splenic masses.

Silencing long non-coding RNA MEG8 inhibits the proliferation and induces the ferroptosis of hemangioma endothelial cells by regulating miR-497-5p/NOTCH2 axis

Even though long non-coding RNA (lncRNA) MEG8 plays vital roles in carcinogenesis of malignances, its roles and mechanisms in hemangioma remain unknown. Therefore, we evaluate the oncogenic roles of MEG8 in hemangioma. Small interfering RNA (siRNA)-mediated depletion of MEG8 inhibited the proliferation and increased MDA level in human hemangioma endothelial cells (HemECs). The inhibitors of ferroptosis (ferrostatin-1 and liproxstatin-1) abolished the MEG8 silence induced cell viability loss. Knockdown of MEG8 increased the miR-497-5p expression and reduced the mRNA and protein levels of NOTCH2. Using a dual-luciferase assay, we confirmed the binding between MEG8 and miR-497-5p, and between the miR-497-5p and 3'UTR of NOTCH2. We further found that silencing MEG8 significantly decreased the expressions of SLC7A11 and GPX4 both in mRNA and protein level and had no effect on the level of AIFM2. Importantly, blocking miR-497-5p abrogated the effects of MEG8 loss on cell viability, MDA level and expression levels of NOTCH2, SLC7A11 and GPX4 in HemECs. Taken together, our results suggested that knockdown of long non-coding RNA MEG8 inhibited the proliferation and induced the ferroptosis of hemangioma endothelial cells by regulating miR-497-5p/NOTCH2 axis.

MicroRNA-497-5p downregulation inhibits cell viability, reduces extracellular matrix deposition and induces apoptosis in human hyperplastic scar fibroblasts by regulating Smad7

Hypertrophic scars (HSs) are characterized by excessive extracellular matrix deposition and excessive growth of dense fibrous tissues. MicroRNAs (miRNAs/miRs) serve key roles in HS formation. The present study investigated the expression, role and mechanism underlying the effects of miR-497-5p in HS formation. miR-497-5p expression was detected via reverse transcription-quantitative PCR. The association between miR-497-5p and Smad7 was analyzed using TargetScan and luciferase reporter assays. Protein expression levels of extracellular matrix markers were measured via western blotting. Cell viability and apoptosis were determined using the Cell Counting Kit-8 assay and flow cytometry, respectively. The results suggested that miR-497-5p expression was upregulated in HS tissues and human HS fibroblasts (hHSFs) compared with healthy control skin tissues and CCC-ESF-1 cells, respectively. Smad7 was directly targeted by miR-497-5p, and was downregulated in HS tissues and hHSFs compared with healthy control skin tissues and CCC-ESF-1 cells, respectively. Moreover, Smad7 upregulation significantly inhibited cell viability, decreased extracellular matrix deposition and induced apoptosis in hHSFs compared with the control-plasmid group. Moreover, the results indicated that, compared with the inhibitor control group, miR-497-5p inhibitor inhibited cell viability, decreased extracellular matrix deposition and induced apoptosis in hHSFs, which were significantly reversed by Smad7 knockdown. In conclusion, the results indicated that miR-497-5p downregulation repressed HS formation by inhibiting extracellular matrix deposition and hHSF proliferation at least partly by targeting Smad7.

MicroRNA-497-5p Functions as a Modulator of Apoptosis by Regulating Metadherin in Ovarian Cancer

Ovarian cancer (OC) has a high mortality rate among women worldwide. However, even with the advances in detection and therapeutics, the number of cases is increasing worldwide. Increasingly, microRNAs (miRNAs), including miR-497-5p, have been implicated in the progression of many cancers, but the role of miR-497-5p in OC remains unknown. The purpose of this study was to investigate the underlying molecular mechanism of miR-497-5p in OC. Herein, we find that miR-497-5p is down-regulated in OC tissues, and overexpression of miR-497-5p enhances apoptosis in OC cells. The increased apoptosis was correlated with enhanced expression of apoptosis-related proteins. MiR-497-5p directly bound the 3'-untranslated region of metadherin (MTDH), leading to the reduction of MTDH in mRNA and protein levels. Moreover, MTDH knockout promoted the apoptosis of OC cells. Taken together, we conclude that miR-497-5p contributes to cell apoptosis in OC by regulating MTDH.

Regulation of microRNA-497 expression in human cancer

MicroRNAs (miRNAs/miRs) are a type of non-coding single-stranded RNA, with a length of ~22 nt, which are encoded by endogenous genes and are involved in the post-transcriptional regulation of gene expression in animals and plants. Studies have demonstrated that miRNAs play an important role in the occurrence, development, metastasis, diagnosis and treatment of cancer. In recent years, miR-497 has been identified as one of the key miRNAs in a variety of cancer types and has been shown to be downregulated in a variety of solid tumors. However, the regulation of miR-497 expression involves a complex network, which is affected by several factors. The aim of the present review was to summarize the mechanism of regulation of miR-497 expression at the pre-transcriptional and transcriptional levels in cancer, as well as the role of miR-497 expression imbalance in cancer diagnosis, treatment and prognosis. The regulatory mechanisms of miR-497 expression may aid in our understanding of the causes of miR-497 expression imbalance and provide a reference value for further research on the diagnosis and treatment of cancer.

LINC00662 contributes to the progression and the radioresistance of cervical cancer by regulating miR-497-5p and CDC25A

It is reported that long intergenic non-coding RNA 00662 (LINC00662) plays an oncogenic role in tumours. However, the mechanism of LINC00662 in regulating the progression and radiosensitivity of cervical cancer (CC) is not clear. In this study, quantitative real-time polymerase chain reaction (qRT-PCR) was adopted to detect LINC00662 and miR-497-5p expressions in CC tissues and cells. The expression of cell division cycle 25 A (CDC25A) in CC cells was examined by Western blot. CC cell proliferation was determined by cell counting kit-8 (CCK-8) and BrdU assays. The survival rate of CC cells was evaluated by colony formation assay under different doses of X-ray irradiation. CC cell migration and invasion were probed by Transwell assay. Besides, the interactions between miR-497-5p and LINC00662, and miR-497-5p and the 3'UTR of CDC25A were verified by dual-luciferase reporter assay, RIP assay, and RNA pull-down experiments. We demonstrated that, LINC00662 expression was remarkably raised in CC tissues and cell lines. LINC00662 overexpression promoted proliferation, migration, invasion and radioresistance of CC cells, and LINC00662 knockdown inhibited the above malignant phenotypes of CC cells. In terms of mechanism, LINC00662 facilitated CC progression and radioresistance by adsorbing miR-497-5p and indirectly up-regulating CDC25A expression. In a word, the LINC00662/miR-497-5p/CDC25A axis boosts proliferation and metastasis of CC cells and enhances the radioresistance of cancer cells. SIGNIFICANCE OF THE STUDY: CC poses a threat to the health of women all over the world. In this study, we demonstrated for the first time that LINC00662 expression was remarkably raised in CC tissues and cells. Cellular experiments confirmed that LINC00662 facilitated cell proliferation, migration, invasion and radiation resistance through the miR-497-5p/CDC25A axis, which might be a promising target for CC treatments.

Insights into the Role of microRNAs in Colorectal Cancer (CRC) Metabolism

Colorectal cancer (CRC) is one of the most frequently diagnosed cancers, with a high mortality rate globally. The pathophysiology of CRC is mainly initiated by alteration in gene expression, leading to dysregulation in multiple signalling pathways and cellular processes. Metabolic reprogramming is one of the important cancer hallmarks in CRC, which involves the adaptive changes in tumour cell metabolism to sustain the high energy requirements for rapid cell proliferation. There are several mechanisms in the metabolic reprogramming of cancer cells, such as aerobic glycolysis, oxidative phosphorylation, lactate and fatty acids metabolism. MicroRNAs (miRNAs) are a class of non-coding RNAs that are responsible for post-transcriptional regulation of gene expression. Differential expression of miRNAs has been shown to play an important role in different aspects of tumorigenesis, such as proliferation, apoptosis, and drug resistance, as well as metabolic reprogramming. Increasing evidence also reports that miRNAs could function as potential regulators of metabolic reprogramming in CRC cells. This review provides an insight into the role of different miRNAs in regulating the metabolism of CRC cells as well as to discuss the potential role of miRNAs as biomarkers or therapeutic targets in CRC tumour metabolism.

Tanshinone IIA regulates human AML cell proliferation, cell cycle, and apoptosis through miR-497-5p/AKT3 axis

Background

The roots of Salvia miltiorrhiza are used in traditional Chinese medicine (TCM) and have high medicinal value. Tanshinone IIA (Tan IIA) is the active ingredient of Salvia miltiorrhiza which can inhibit the growth of acute leukemia cell lines in vitro, although the mechanism remains unclear.

Methods

CCK-8 assays and BrdU stain were used to evaluate cell proliferation ability. Western blot analysis was used to detect protein expression. miR-497-5p expression level was detected by using qRT-PCR, and Annexin V-FITC/propidium iodide (PI) was used to detect cell apoptosis.

Results

Here we reported that Tan IIA could inhibit cell proliferation, induce cell cycle arrest, and promote cell apoptosis in acute myeloid leukemia (AML) cells. Thus, Tan IIA had the anti-cancer activity in AML cell lines, which was likely mediated by up-regulation of miR-497-5p expression. Our data further showed that in AML cells, the same effects were observed with overexpression of miR-497-5p by a miR-497-5p mimic. We demonstrated that Tan IIA could inhibit the expression of AKT3 by up-regulating the expression of miR-497-5p. We subsequently identified that AKT3 was the direct target of miR-497-5p, and that treatment with Tan IIA obviously reversed the effect of treatment with an miR-497-5p inhibitor under harsh conditions. In turn, PCNA expression was increased and cleaved Caspase-3 was suppressed, which contributed to the growth of AML cells.

Conclusions

Our results showed that Tan IIA could inhibit cell proliferation in AML cells through miR-497-5p-mediated AKT3 downregulation pathway.

miR-497-5p mediates starvation-induced death in colon cancer cells by targeting acyl-CoA synthetase-5 and modulation of lipid metabolism

Modulation of fatty acids metabolism is an appropriate strategy for starvation-induced death in tumor cancers. Colon cancer cells express a high level of acyl-CoA synthetase-5 (ACSL5), and as yet no therapeutic approach has been achieved. Herein, ACSL5-related microRNAs (miRNAs) were identified via TargetScan, and their impacts on ACSL5 and lipid content along with metabolic activity, cell cycle, migration, and invasion of colorectal cancer (CRC) cells were examined, and subsequently compared with transcriptome for better visualization of intracellular-signaling networks. In vivo analysis was performed using BALB/c mice xenograft model of CRC injected with target miRNA. Clinical significances were also evaluated in 80 CRC tumors and matched adjacent normal tissues. There was a reverse correlation between ACSL5 and miR-497-5p, which miR-497-5p overexpression modulated CRC cell proliferation and development. A similar observation was received from the in vivo examination in which intratumoral injection of miR-497-5p reversed the tumor growth in the CRC xenograft model. Downregulation of miR-497-5p correlated with tumor differentiation, tumor, node, and metastasis staging, lymph node metastasis, and poor survival in patients with CRC. These results suggested that miR-497-5p upregulation could be considered as a therapeutic strategy for modulation of lipid metabolism in colon cancer.

circRNA-14723 promotes hepatocytes proliferation in rat liver regeneration by sponging rno-miR-16-5p

Circular RNA (circRNA) is a subclass of noncoding RNA (ncRNA) detected within mammalian tissues and cells. However, its regulatory role during the proliferation phase of rat liver regeneration (LR) remains unreported. This study was designed to explore their regulatory mechanisms in cell proliferation of LR. The circRNA expression profile was detected by high-throughput sequencing. It was indicated that 260 circRNAs were differentially expressed during the proliferation phase of rat LR. Among them, circ-14723 displayed a significantly differential expression. We further explored its regulatory mechanism in rat hepatocytes (BRL-3A cells). First, EdU, flow cytometry and western blot (WB) indicated that knocking down circ-14723 inhibited BRL-3A cells proliferation. Second, RNA-Pulldown and dual-luciferase report assay showed that circ-14723 could sponge rno-miR-16-5p. At last, WB showed that the reported target genes of rno-miR-16-5p, CCND1, and CCNE1 were downregulated after knocking down circ-14723. In conclusion, we found that circ-14723 exerted a critical role in G1/S arrest to promote cell proliferation via rno-miR-16-5p/CCND1 and CCNE1 axis in rat LR. This finding further revealed the regulatory mechanisms of circRNA on cell proliferation of LR, and might provide a potential target for clinical problems.

Circular RNA Profiling Reveals That circRNA_104433 Regulates Cell Growth by Targeting miR-497-5p in Gastric Cancer

BACKGROUND

The role and mechanism of hsa_circRNA_104433 in gastric cancer (GC) are further elucidated.

MATERIALS AND METHODS

CircRNA_104433 was selected by circRNA microarrays and GEO database. qRT-PCR was used to analyze the expression of circRNA_104433 in GC. The role of circRNA_104433 in GC cells was evaluated based on cell cycle progression, cell proliferation, cell apoptosis, and tumor xenograft experiment assay. To explore the mechanisms of circRNA_104433 in GC TCGA database, STRING version, qRT-PCR and luciferase assay were performed. Furthermore, the prognostic value of CDC25A in GC was determined based on the GEO database.

RESULTS

The level of circRNA_104433 showed upregulation in GC tissues, and the expression of it showed a positive correlation with the degree of differentiation and the size of the tumor. Knockdown of circRNA_104433 inhibited cell cycle transition, and cell proliferation, while promoted cell apoptosis in GC. CircRNA_104433 directly binds to miR-497-5p, which directly regulates CDC25A. The median survival period of GC patients with high expression levels of CDC25A was 21.3 months, which was shorter than those with low group expression of CDC25A (35.9 months). The cell cycle proteins CDK1, CDK2, CCNB1, PKMYT1, CDC20, CHEK1 and CDC25A were coexpressed with CDC25A.

CONCLUSION

These findings suggested that knockdown of circRNA_104433 expression suppressed tumor development in GC.

LINC00473/miR-497-5p Regulates Esophageal Squamous Cell Carcinoma Progression Through Targeting PRKAA1

Background: Esophageal squamous cell carcinoma (ESCC) is one of the esophageal cancers known as an aggressive malignant tumor. Long noncoding RNAs (lncRNAs) can be involved in the progression and development of cancers. lncRNA LINC00473 (LINC00473) was reported to exert an oncogenic influence on diverse cancers. However, neither the biological function nor the underlying mechanism of LINC00473 has been explored in ESCC. Aim of the Study: The aim of investigation is to explore the role of LINC00473 in ESCC. Methods: The expression of LINC00473, miR-497-5p, and protein kinase AMP-activated alpha 1 catalytic subunit (PRKAA1) was detected by reverse-transcription quantitative polymerase chain reaction assay. Cell counting kit-8 and 5-ethynyl-2'-deoxyuridine assays were carried out to measure cell proliferation. Cell migration was tested by transwell assay. Western blot assay was performed to examine the protein expression of PRKAA1, E-cadherin, N-cadherin, and Vimentin. The binding capacity between miR-497-5p and LINC00473 (or PRKAA1) was, respectively, studied by luciferase reporter and RNA immunoprecipitation assays. Pearson correlation analysis was adopted to analyze the correlation between miR-497-5p (or LINC00473) and PRKAA1. Results: LINC00473 presented much higher expression and LINC00473 suppression restrained the proliferation, migration, and epithelial-mesenchymal transition (EMT) process in ESCC cells. MiR-497-5p presented lower expression, binding with and negatively regulated by LINC00473 in ESCC. PRKAA1 was confirmed as a downstream target gene for miR-497-5p. PRKAA1 could combine with miR-497-5p, and LINC00473 knockdown or miR-497-5p overexpression downregulated the mRNA and protein expression of PRKAA1. At last, the inhibitory effects of LINC00473 knockdown on proliferation, migration, and EMT process were reversed by PRKAA1 overexpression in vitro and in vivo. Conclusions: LINC00473 regulates ESCC progression through miR-497-5p/PRKAA1 axis, which provides a new therapeutic strategy for ESCC patients.

MicroRNA-497-5p negatively regulates the proliferation and cisplatin resistance of non-small cell lung cancer cells by targeting YAP1 and TEAD1

BACKGROUND

MicroRNAs (miRNAs) are crucial regulators in the pathological processes and drug resistance of lung cancer. In this study, we investigated the role of miR-497-5p in modulating the function of non-small cell lung cancer (NSCLC).

METHODS

MiR-497-5p expression in lung cancer tissues and cells was evaluated by qRT-PCR. Cell proliferation was evaluated by CCK-8 assay and colony-formation assay. Cell cycle and cell apoptosis were detected by flow cytometry. The effect of miR-497-5p on the expression of Yes-associated protein 1 (YAP1) and TEA domain family member 1 (TEAD1) was analyzed by qRT-PCR, Western blot and luciferase activity assay.

RESULTS

The expression of miR-497-5p was significantly downregulated in lung cancer tissues and cells compared with paired normal tissues and cells. Overexpression of miR-497-5p induced growth retardation and apoptosis of A549 lung cancer cells. Mechanistically, YAP1 and TEAD1 were targeted and downregulated by miR-497-5p. Finally, we found that miR-497-5p increased cisplatin chemosensitivity in A549 cells.

CONCLUSIONS

MiR-497-5p suppresses cell proliferation and resistance to cisplatin in NSCLC by downregulating the expression of YAP1 and TEAD1.

miR-497-5p inhibits gastric cancer cell proliferation and growth through targeting PDK3

MicroRNA plays an important role in gastric cancer (GC) development, while the function of miR-497-5p in this disease remains unknown. In the present study, we demonstrated miR-497-5p as a tumor suppressive microRNA in GC. miR-497-5p was down-regulated in GC tissues and its expression was associated with the disease stage. Inhibition of miR-497-5p promoted GC cell proliferation and growth. By contrast, miR-497-5p ectopic expression suppressed the proliferation and growth of GC cells. In addition, miR-497-5p inhibited DNA synthesis and enhanced apoptosis in GC cells. The cell cycle progression was suppressed by miR-497-5p. Mechanistically, miR-497-5p directly targeted and suppressed the expression of pyruvate dehydrogenase kinase 3 (PDK3), which is highly expressed in GC tissues. Over-expression of PDK3 promoted the proliferation of GC cells. Our study revealed that miR-497-5p inhibited GC cell proliferation and growth via targeting PDK3.

Up-regulation of microRNA-497-5p inhibits colorectal cancer cell proliferation and invasion via targeting PTPN3

To investigate the role of microRNA-497-5p (miR-497-5p) in the tumorigenesis of colorectal cancer (CRC), the present study applied qRT-PCR to detect the expression level of miR-497-5p in both clinical samples and CRC cell lines. Furthermore, to specifically evaluate the carcinogenic role of miR-497-5p in CRC, the expression of miR-497-5p was monitored by transfecting with the mimics or inhibitors of miR-497-5p. Transwell assay as well as CCK-8 assay were used to determine the functions of miR-497-5p on cell invasion, migration and proliferation, respectively. miR-497-5p expression was remarkably down-regulated in clinical samples with cancer development as well as in CRC cell lines. Additionally, low miR-497-5p expression was remarkably correlated with higher TNM stage and lymph node metastasis of CRC patients. Up-regulation of miR-497-5p significantly inhibited proliferation, migration, and invasion of LOVO CRC cell line. Conversely, antagonizing miR-497-5p significantly promoted cell proliferation, migration and invasion. Mechanistic analysis revealed that miR-497-5p directly bound to its downstream target, protein tyrosine phosphatase non-receptor type 3 (PTPN3), whose aberrant expression partially reversed inhibition of cell proliferation and migration. Taken together, the present study elucidated the inhibitory role of miR-497-5p in CRC via targeting PTPN3, which potentiated miR-497-5p as a potential therapeutic target for combating CRC.

MicroRNA-655-3p and microRNA-497-5p inhibit cell proliferation in cultured human lip cells through the regulation of genes related to human cleft lip

Background

The etiology of cleft lip with or without cleft palate (CL/P), a common congenital birth defect, is complex and involves the contribution of genetic and environmental factors. Although many candidate genes have been identified, the regulation and interaction of these genes in CL/P remain unclear. In addition, the contribution of microRNAs (miRNAs), non-coding RNAs that regulate the expression of multiple genes, to the etiology of CL/P is largely unknown.

Methods

To identify the signatures of causative biological pathways for human CL/P, we conducted a systematic literature review for human CL/P candidate genes and subsequent bioinformatics analyses. Functional enrichment analyses of the candidate CL/P genes were conducted using the pathway databases GO and KEGG. The miRNA-mediated post-transcriptional regulation of the CL/P candidate genes was analyzed with miRanda, PITA, and TargetScan, and miRTarbase. Genotype-phenotype association analysis was conducted using GWAS. The functional significance of the candidate miRNAs was evaluated experimentally in cell proliferation and target gene regulation assays in human lip fibroblasts.

Results

Through an extensive search of the main biomedical databases, we mined 177 genes with mutations or association/linkage reported in individuals with CL/P, and considered them as candidate genes for human CL/P. The genotype-phenotype association study revealed that mutations in 12 genes (ABCA4, ADAM3A, FOXE1, IRF6, MSX2, MTHFR, NTN1, PAX7, TP63, TPM1, VAX1, and WNT9B) were significantly associated with CL/P. In addition, our bioinformatics analysis predicted 16 microRNAs (miRNAs) to be post-transcriptional regulators of CL/P genes. To validate the bioinformatics results, the top six candidate miRNAs (miR-124-3p, miR-369-3p, miR-374a-5p, miR-374b-5p, miR-497-5p, and miR-655-3p) were evaluated by cell proliferation/survival assays and miRNA-gene regulation assays in cultured human lip fibroblasts. We found that miR-497-5p and miR-655-3p significantly suppressed cell proliferation in these cells. Furthermore, the expression of the predicted miRNA-target genes was significantly downregulated by either miR-497-5p or miR-655-3p mimic.

Conclusion

Expression of miR-497-5p and miR-655-3p suppresses cell proliferation through the regulation of human CL/P-candidate genes. This study provides insights into the role of miRNAs in the etiology of CL/P and suggests possible strategies for the diagnosis of CL/P.

Electronic supplementary material

The online version of this article (10.1186/s12920-019-0535-2) contains supplementary material, which is available to authorized users.

HOXC13-AS promotes breast cancer cell growth through regulating miR-497-5p/PTEN axis

Dysregulated long noncoding RNAs (lncRNAs) remains to be explored in tumorigenesis. LncRNA HOXC13 antisense RNA (HOXC13-AS) has been found as an oncogene in many cancers; however, the role of HOXC13-AS in breast cancer still elusive. In this study, the HOXC13-AS levels and its role in cell proliferation was first measured by real-time quantitative polymerase chain reaction, Cell Counting Kit-8 assay, and colony formation assay. It showed that HOXC13-AS was increased in breast cancer tissues compared with the adjacent normal tissues and upregulated HOXC13-AS promoted the growth of breast cancer cells. Then, we found that the miR-497-5p levels were downregulated in cancer tissues compared with the adjacent tissues and miR-497-5p suppressed breast cancer cell proliferation. Further study showed that HOXC13-AS could function as a "sponge" for miR-497-5p then suppress miR-497-5p expression. Moreover, we next identified that Phosphatase and Tensin homolog (PTEN) is the target of miR-497-5p. Overexpression of miR-497-5p by chemical mimics decreased the expression of PTEN, while downregulation of miR-497-5p by HOXC13-AS rescued the expression of PTEN. Finally, we showed that HOXC13-AS promoted the proliferation of breast cancer cells and tumor growth through miR-497-5p/PTEN axis in vitro and in vivo. Hence, we conclude that HOXC13-AS, which is significantly upregulated in breast cancers, promoted cell proliferation through the suppressed miR-497-5p and further upregulated PTEN.

Potent and PPARα-independent anti-proliferative action of the hypolipidemic drug fenofibrate in VEGF-dependent angiosarcomas in vitro

Angiosarcomas are highly aggressive tumors of endothelial origin, which carry a poor prognosis. Fenofibrate is a hypolipidemic drug, which acts by activating the transcription factor PPARα. It has also been widely reported to have ‘anti-cancer’ activity. The current study investigated its effect in a murine VEGF-dependent angiosarcoma cell-line, MS1 VEGF. The study utilised assays to monitor cell proliferation and viability, apoptosis, cell cycle progression, mitochondrial membrane potential, changes in protein expression, and changes in miRNA expression using microarrays. Fenofibrate showed potent anti-proliferative action in MS1 VEGF angiosarcoma cells, without inducing apoptosis. It enriched cells in G2/M cell cycle phase and hyperpolarised mitochondria. Other PPARα activators failed to mimic fenofibrate action. Inhibitors of PPARα and NFκB failed to reverse the inhibitory effect of fenofibrate and their combination with fenofibrate was cytotoxic. Fenofibrate downregulated the expression of key VEGF-effector proteins, including Akt, ERK, Bcl-2 and survivin, and a chemical inhibitor screen discovered relevance of these proteins to cell proliferation. A miRNA microarray revealed that fenofibrate differentially regulated cellular miRNAs with known roles in cancer and angiogenesis. The data raise the possibility that fenofibrate could be useful in angiosarcoma therapy, especially considering its well-established clinical safety and tolerability profile.

The potassium channel KCa3.1 promotes cell proliferation by activating SKP2 and metastasis through the EMT pathway in hepatocellular carcinoma

The intermediate conductance calcium-activated potassium channel (KCa3.1) plays an important role in maintaining intracellular calcium homeostasis and is involved in the tumorigenesis of many human cancers. However, it is unknown whether KCa3.1 plays a role in the genesis of hepatocellular carcinoma (HCC), one of the most common malignant tumors worldwide with a very poor prognosis. In our study, we found that the expression of KCa3.1 was significantly elevated in poorly differentiated HCC tissues compared to adjacent noncancerous tissues. In vitro and in vivo experiments showed that KCa3.1 could promote cell proliferation, migration, and invasion of HCC. Mechanistically, KCa3.1 promoted cell cycle progression and migration and invasion of HCC cells by activating S-phase protein kinase 2 (SKP2) to trigger the degradation of p21 and p27 and targeting Reelin (RELN) to induce epithelial-mesenchymal transition (EMT), respectively. Taken together, our results demonstrate that KCa3.1 plays an important role in the genesis and progression of HCC, implying that it might be a promising therapeutic target in HCC.

Cancer-Associated Intermediate Conductance Ca2+-Activated K⁺ Channel KCa3.1

Several tumor entities have been reported to overexpress K_Ca3.1 potassium channels due to epigenetic, transcriptional, or post-translational modifications. By modulating membrane potential, cell volume, or Ca²⁺ signaling, K_Ca3.1 has been proposed to exert pivotal oncogenic functions in tumorigenesis, malignant progression, metastasis, and therapy resistance. Moreover, K_Ca3.1 is expressed by tumor-promoting stroma cells such as fibroblasts and the tumor vasculature suggesting a role of K_Ca3.1 in the adaptation of the tumor microenvironment. Combined, this features K_Ca3.1 as a candidate target for innovative anti-cancer therapy. However, immune cells also express K_Ca3.1 thereby contributing to T cell activation. Thus, any strategy targeting K_Ca3.1 in anti-cancer therapy may also modulate anti-tumor immune activity and/or immunosuppression. The present review article highlights the potential of K_Ca3.1 as an anti-tumor target providing an overview of the current knowledge on its function in tumor pathogenesis with emphasis on vasculo- and angiogenesis as well as anti-cancer immune responses.

Non-Coding RNAs in Breast Cancer: Intracellular and Intercellular Communication

Non-coding RNAs (ncRNAs) are regulators of intracellular and intercellular signaling in breast cancer. ncRNAs modulate intracellular signaling to control diverse cellular processes, including levels and activity of estrogen receptor α (ERα), proliferation, invasion, migration, apoptosis, and stemness. In addition, ncRNAs can be packaged into exosomes to provide intercellular communication by the transmission of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) to cells locally or systemically. This review provides an overview of the biogenesis and roles of ncRNAs: small nucleolar RNA (snRNA), circular RNAs (circRNAs), PIWI-interacting RNAs (piRNAs), miRNAs, and lncRNAs in breast cancer. Since more is known about the miRNAs and lncRNAs that are expressed in breast tumors, their established targets as oncogenic drivers and tumor suppressors will be reviewed. The focus is on miRNAs and lncRNAs identified in breast tumors, since a number of ncRNAs identified in breast cancer cells are not dysregulated in breast tumors. The identity and putative function of selected lncRNAs increased: nuclear paraspeckle assembly transcript 1 (NEAT1), metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), steroid receptor RNA activator 1 (SRA1), colon cancer associated transcript 2 (CCAT2), colorectal neoplasia differentially expressed (CRNDE), myocardial infarction associated transcript (MIAT), and long intergenic non-protein coding RNA, Regulator of Reprogramming (LINC-ROR); and decreased levels of maternally-expressed 3 (MEG3) in breast tumors have been observed as well. miRNAs and lncRNAs are considered targets of therapeutic intervention in breast cancer, but further work is needed to bring the promise of regulating their activities to clinical use.

Ca2+-Activated K+ Channel KCa3.1 as a Therapeutic Target for Immune Disorders

In lymphoid and myeloid cells, membrane hyperpolarization by the opening of K⁺ channels increases the activity of Ca²⁺ release-activated Ca²⁺ (CRAC) channels and transient receptor potential (TRP) Ca²⁺ channels. The intermediate-conductance Ca²⁺-activated K⁺ channel K_Ca3.1 plays an important role in cell proliferation, differentiation, migration, and cytokine production in innate and adaptive immune systems. K_Ca3.1 is therefore an attractive therapeutic target for allergic, inflammatory, and autoimmune disorders. In the past several years, studies have provided new insights into 1) K_Ca3.1 pharmacology and its auxiliary regulators; 2) post-transcriptional and proteasomal regulation of K_Ca3.1; 3) K_Ca3.1 as a regulator of immune cell migration, cytokine production, and phenotypic polarization; 4) the role of K_Ca3.1 in the phosphorylation and nuclear translocation of Smad2/3; and 5) K_Ca3.1 as a therapeutic target for cancer immunotherapy. In this review, we have assembled a comprehensive overview of current research on the physiological and pathophysiological significance of K_Ca3.1 in the immune system.

T2DM inhibition of endothelial miR-342-3p facilitates angiogenic dysfunction via repression of FGF11 signaling

Understanding the function and molecular relevance of distinct miRNAs in endothelial cells (ECs) paves avenues for possible therapeutic intervention by targeting epigenetic mechanisms in vascular endothelial dysfunction, one of the major complications of type 2 diabetes mellitus (T2DM). MiR-342-3p, an obesity-associated miRNA, has recently been shown to be significantly upregulated in human angiosarcoma compared to benign hemangioma, indicating its potential involvement as a proangiogenic factor. Herein, we show that endothelial miR-342-3p expression was significantly compromised in T2DM organisms and this inhibition powerfully blocked vasculogenesis in vivo by repressing endothelial proliferation and migration. From a mechanistic standpoint, miR-342-3p promoted the transactivation of fibroblast growth factor 11 (FGF11) by directly targeting its 3' untranslated regions (3'UTRs). Functionally, overexpression of exogenous FGF11 successfully rescued miR-342-3p deficiency-impaired endothelial proliferation and migration. Thus, perturbation of miR-342-3p/FGF11 cascade by hyperinsulinemia plays a causative role in the induction of vascular dysfunction in T2DM. Overall, the current study underscore an endothelial facet of miR-342-3p, which may operate as a novel epigenetic integrator linking adipogenic homeostasis and angiogenesis.

MiR-497-5p, miR-195-5p and miR-455-3p function as tumor suppressors by targeting hTERT in melanoma A375 cells

Background

hTERT gene plays an important role in melanoma, although the specific mechanism involved is unclear. The aim of this study was to screen and identify the relative miRNAs with the regulation of hTERT in melanoma.

Materials and methods

Quantitative real-time polymerase chain reaction (q-PCR) and immunohistochemistry were performed to detect hTERT mRNA and protein expression in 36 formalin-fixed paraffin-embedded melanoma tissues and 36 age- and sex-matched pigmented nevi cases, respectively. Bioinformatics analysis and custom miRNA polymerase chain reaction array were determined for predicting, screening and verifying miRNAs with the regulation of the hTERT gene. To investigate the biological functions, miRNAs mimics or inhibitors were transfected into melanoma A375 cells. The relative expression of miR-497-5p, miR-195-5p, miR-455-3p and hTERT mRNA was determined by q-PCR. The protein expression of hTERT was detected by Western blot. 3-(4,5-Dimethylthiazolyl-2-yl)-2,5-biphenyl tetrazolium bromide and flow cytometry were employed to detect cell proliferation ability, cell apoptosis and cell cycle. Transwell and wound healing assays were used to observe cell invasion and migration abilities. A direct target gene of miRNAs was analyzed by a dual luciferase reporter activity assay.

Results

MiR-497-5p, miR-195-5p, miR-455-3p were significantly downregulated, while hTERT was upregulated in melanoma tissues. hTERT expression level was inversely correlated with miR-497-5p, miR-195-5p and miR-455-3p. Overexpression of miR-497-5p, miR-195-5p and miR-455-3p inhibited A375 cell proliferation, migration and invasion, arrested the cell cycle, induced cell apoptosis and decreased hTERT expression at both mRNA and protein levels. Suppression of miR-497-5p, miR-195-5p and miR-455-3p partially reversed the inhibitory effects. Finally, hTERT was identified as a direct target of miR-497-5p, miR-195-5p and miR-455-3p.

Conclusions

MiR-497-5p, miR-195-5p and miR-455-3p act as tumor suppressors by targeting hTERT in melanoma A375 cells. Therefore, miR-497-5p, miR-195-5p and miR-455-3p could be potential targeted therapeutic choice for melanoma.

MicroRNA-340 inhibits the growth and invasion of angiosarcoma cells by targeting SIRT7

MicroRNAs (miRNAs) are emerging as critical regulators for the development and progression of various cancers, including angiosarcoma. Accumulating evidence suggests that miRNA-340 (miR-340) is an important cancer-associated miRNA. However, little is known about the role of miR-340 in angiosarcoma. In this study, we aimed to investigate the potential biological functions of miR-340 and its potential target gene in angiosarcoma. Our results showed that miR-340 expression was significantly decreased in angiosarcoma compared with normal controls. The overexpression of miR-340 inhibited the growth and invasion of angiosarcoma cells, while the inhibition of miR-340 showed the opposite effect. Bioinformatics analysis predicted that Sirtuin 7 (SIRT7) was a potential target gene of miR-340. The binding relationship between miR-340 and the SIRT7 3'-untranslated region was verified by dual-luciferase reporter assay. Moreover, our results showed that miR-340 negatively regulated SIRT7 expression in angiosarcoma cells and an inverse correlation between miR-340 and SIRT7 expression was shown in clinical angiosarcoma tissues. We found that silencing SIRT7 significantly inhibited the proliferation and invasion of angiosarcoma cells. Notably, the overexpression of SIRT7 promoted the proliferation and invasion of angiosarcoma cells and also partially reversed the antitumor effect of miR-340 on angiosarcoma cell proliferation and invasion. Taken together, our results demonstrate that miR-340 inhibits the growth and invasion of angiosarcoma cells by targeting SIRT7. Our study provides evidence that the miR-340/SIRT7 axis may play an important role in the molecular pathogenesis of angiosarcoma and suggests that miR-340 and SIRT7 may be used as potential and novel therapeutic targets for the treatment of angiosarcoma.

Cutaneous angiosarcoma: update on biology and latest treatment

PURPOSE OF REVIEW

The present review aims to provide readers with the latest updates on the biology and clinical management of cutaneous angiosarcoma (cAS).

RECENT FINDINGS

The genomic alteration of cAS is heterogeneous. Mutations are enriched in the mitosis-activated kinase (MAPK) pathway. Functional analysis has identified molecules that may serve as potential markers and therapeutic targets of angiosarcoma. These molecules include survivin, HSP90, FOXM1, miR-497-5p, KCa3.1, and miR210.This body of knowledge has not yet transferred to clinical practice. The mainstay of treatment for cAS remains surgery followed by postoperative radiotherapy. The efficacy of paclitaxel as an adjuvant chemotherapy is suggested.For patients with advanced cAS, paclitaxel is the treatment of choice. There are also second-line treatment options that are supported by evidence of varying strength. A multikinase inhibitor, pazopanib, has been assessed in several studies, most of which support its efficacy for angiosarcoma. Bevacizumab monotherapy may be effective for angiosarcoma. The efficacy of eribulin mesylate and trabectedin for angiosarcoma is currently being assessed. Recent publications highlighted the role of the immune system in the biology of cAS.

SUMMARY

Future research efforts should focus on the following aspects of cAS: drug development directed at recent molecular targets, clinical trials designed specifically for patients with cAS, and the role of immunotherapy for cAS.

Role of miR-483 in digestive tract cancers: from basic research to clinical value

Digestive tract cancers (DTCs) is the most common malignant tumors in the world. Despite surgery and medical technology have witnessed the increasing development and sharp advancement in the past decade, DTCs remain a critical concern with high morbidity and mortality. Since a class of small noncoding RNAs termed miRNAs were identified several years ago, increasing studies have attempted to illustrate the relationship between the specific miRNAs dysregulated expression levels and the diseases phenotypic changes. For example, microRNA-483 (miR-483) aberrant expression plays a pivotal part in tumor biology in a variety of human cancer, including DTCs. In this review, we focus on the present key findings from recent profiling studies, discuss the use of miR-483 as a novel biomarker for DTCs. At the same time, we emphasize the significant diversities and technical difficulties must be overcome before clinically relevant signatures arose. It is believed that this might provide researchers an insight into the molecular targeting cancer treatment.