MicroRNA-338-3p inhibits the progression of bladder cancer through regulating ETS1 expression

Circular RNA DHTKD1 targets miR‑338‑3p/ETS1 axis to regulate the inflammatory response in human bronchial epithelial cells

Asthma is a chronic inflammatory airway disease and the airway epithelium is involved in airway inflammation and innate immunity. However, whether circular RNA (circRNA) is involved in the pathogenesis of asthma remains unclear. The present study aimed to determine the functions and molecular mechanisms of circRNA targeting dehydrogenase E1 (circDHTKD1) in the inflammation response of human bronchial epithelial cells. BEAS-2B cells were stimulated with lipopolysaccharide (LPS) to establish a model of in vitro airway inflammation. Cell viability was assessed using Cell Counting Kit-8 assay. CircDHTKD1 was characterised by nucleocytoplasmic isolation and Sanger sequencing. The RNA expression levels of circDHTKD1, microRNA (miR)-338-3p and potential ERK pathway downstream genes were evaluated by reverse transcription-quantitative polymerase chain reaction. Western blot analysis was performed to measure associated protein levels. The levels of inflammatory cytokines were detected by ELISA. The interaction between circDHTKD1 and miR-338-3p was confirmed by dual-luciferase reporter assay. circDHTKD1 expression was significantly upregulated by LPS treatment, whereas miR-338-3p expression was decreased. Furthermore, circDHTKD1 directly targeted miR-338-3p, which negatively regulated expression of E26 transformation specific-1 (ETS1). Inflammatory cytokine and ETS1 expression levels decreased following transfection with small interfering RNA targeting circDHTKD1 or miR-338-3p mimics. In addition, co-transfection with miR-338-3p inhibitor reversed the effects caused by circDHTKD1 knockdown. The knockdown of ETS1 in LPS-induced BEAS-2B cells resulted in decreased cytokine production and inhibition of the ERK signalling pathway. Overall, these results suggested that the knockdown of circDHTKD1 alleviated the LPS-induced production of inflammatory cytokines and activation of the ERK pathway in BEAS-2B cells through the miR-338-3p/ETS1 axis. In summary, circDHTKD1 exacerbated LPS-triggered inflammation responses in BEAS-2B cells by regulating ETS1 expression by interacting with miR-338-3p, suggesting that circDHTKD1 may serve as a potential therapeutic target against asthma.

CDH1 overexpression predicts bladder cancer from early stage and inversely correlates with immune infiltration

Background

Bladder cancer (BC) seriously endangers public health, but effective biomarkers for BC diagnosis, particularly in the early stage, are still lacking. Identification of reliable biomarkers associated with early-stage BC is of great importance to early treatment and an improved outcome.

Methods

Differentially expressed genes (DEGs) were identified using four publicly available early-stage BC gene-expression profiles. Protein–protein interaction (PPI) and survival analysis for hub genes was evaluated. The correlation between methylation of genes and prognosis was evaluated using the MethSurv database. Co-expressed genes were explored using Cancer Cell Line Encyclopedia database and the corresponding expression were assessed in vitro. The competing endogenous RNA network and the immune cell infiltration in BC were generated using data of The Cancer Genome Atlas.

Results

Ten hub genes of the 213 integrated DEGs were identified, including CDH1, IGFBP3, PPARG, SDC1, EPCAM, ACTA2, COL3A1, TPM1, ACTC1, and ACTN1. CDH1 appeared to increase from tumor initiation stage and negatively correlated with methylation. Six methylated sites in CDH1 indicated a good prognosis and one site indicated an aberrant prognosis. High CDH1 expression was negatively correlated with infiltrations by most immune cells, such as plasmacytoid dendritic cells (pDCs), regulatory T cells, macrophages, neutrophils, DCs, and natural killer cells. CDH1 was highly positively correlated with EPCAM and appeared to be directly regulated by miR-383.

Conclusions

The identified oncogenic alterations provide theoretical support for the development of novel biomarkers to advance early-stage BC diagnosis and personalized therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12894-022-01103-7.

Exosomal miR-338-3p suppresses non-small-cell lung cancer cells metastasis by inhibiting CHL1 through the MAPK signaling pathway

Globally, lung cancer remains one of the most prevalent malignant cancers. However, molecular mechanisms and functions involved in its pathogenesis have not been clearly elucidated. This study aimed to evaluate the specific regulatory mechanisms of exosomal miR-338-3p/CHL1/MAPK signaling pathway axis in non-small-cell lung cancer. Western blotting and qRT-PCR (reverse transcription-polymerase chain reaction) were used to determine the expression levels of CHL1 and exosomal miR-338-3p in NSCLC (non-small-cell lung cancer). The CHL1 gene was upregulated and downregulated to evaluate its functions in NSCLC progression. In vitro MTS and apoptotic assays were used to investigate the functions of CHL1 and exosomal miR-338-3p in NSCLC progression. The high-throughput sequencing was used to explore differently expressed exosomal miRNAs. The biological relationships between MAPK signaling pathway and CHL1 and exosomal miR-338-3p in NSCLC were predicted through bioinformatics analyses and verified by western blotting. Elevated CHL1 levels were observed in NSCLC tissues and cells. Upregulated CHL1 expression enhanced NSCLC cells’ progression by promoting tumor cells proliferation while suppressing their apoptosis. Conversely, the downregulation of the CHL1 gene inhibited NSCLC cells’ growth and promoted tumor cells’ apoptotic rate. Additionally, CHL1 activated the MAPK signaling pathway. Besides, we confirmed that miR-338-3p directly sponged with CHL1 to mediate tumor cells progression. Moreover, exosomal miR-338-3p serum levels in NSCLC patients were found to be low. BEAS-2B cells can transfer exosomal miR-338-3p to A549 cells and SK-MES-1 cells. In addition, elevated exosomal miR-338-3p levels significantly inhibited tumor cells proliferation and promoted their apoptosis by suppressing activation of the MAPK signaling pathway. Exosomal miR-338-3p suppresses tumor cells' metastasis by downregulating the expression of CHL1 through MAPK signaling pathway inactivation.

LncRNA CASC15 Promotes Cerebral Ischemia/Reperfusion Injury via miR-338-3p/ETS1 Axis in Acute Ischemic Stroke

Purpose

Acute ischemic stroke (AIS) is a leading health problem caused by cerebral ischemia/reperfusion (CI/R). This study aimed to unveil the potential clinical value and mechanism of lncRNA CASC15.

Patients and Methods

The expression of CASC15, miR-338-3p was detected by quantitative real-time PCR (qRT-PCR). The correlations between CASC15 and national institutes of health stroke scale (NIHSS) scores or miR-338-3p were evaluated by Pearson correlation. A receiver operating characteristic (ROC) curve was performed to provide the diagnostic value of CASC15. Cell Counting Kit-8 (CCK-8) and flow cytometer were used to detect the condition of cell viability and apoptosis. The levels of interleukin-1beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) was detected by enzyme-linked immunosorbent assay (ELISA) assay.

Results

The expression of CASC15 was increased and the levels of miR-338-3p were decreased in AIS patients. A positive association between CASC15 and NIHSS score and an inverse association between CASC15 and miR-338-3p were revealed by Pearson correlation. CASC15 might discriminate AIS patients from healthy people. Silenced CASC15 exerted neuroprotective roles on cell viability, apoptosis, and inflammation via the miR-338-3p/ETS1 axis.

Conclusion

CASC15 might act as a potential diagnostic biomarker for AIS patients. CASC15/miR-338-3p/ETS1 axis played an essential role in cell viability, apoptosis, and neuroinflammation.

Circ-TFF1 Facilitates Breast Cancer Development via Regulation of miR-338-3p/FGFR1 Axis

Some circular RNAs (circRNAs) have been verified to act as essential regulators in the progression of breast cancer (BC). We aimed to investigate the role of circRNA trefoil factor 1 (circ-TFF1) in BC progression. The expression of circ-TFF1, microRNA-338-3p (miR-338-3p) and fibroblast growth factor receptor 1 (FGFR1) mRNA was measured by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation was evaluated by methylthiazolyldiphenyl-tetrazolium bromide (MTT), colony formation, and 5-Ethynyl-2'-deoxyuridine (EDU) assays. Cell apoptosis and invasion were assessed by flow cytometry and transwell assay, respectively. Cellular glycolysis, including glucose consumption, lactate production, and ATP/ADP ratio, was detected by commercial kits. All protein levels were measured by western blot assay. The relationship between miR-338-3p and circ-TFF1 or FGFR1 was predicted by online bioinformatics tool and verified by dual-luciferase reporter assay. Xenograft tumor model was established to verify the function of circ-TFF1 in vivo. Circ-TFF1 was overexpressed in BC tissues and cells. Circ-TFF1 knockdown inhibited cell proliferation, invasion and glycolysis and induced apoptosis in BC cells. Circ-TFF1 acted as a sponge of miR-338-3p, and the effects of circ-TFF1 knockdown on BC cell proliferation, apoptosis, invasion, and glycolysis were abolished by miR-338-3p inhibition. FGFR1 was confirmed to be a target gene of miR-338-3p, and miR-338-3p played a tumor-suppressive role in BC by targeting FGFR1. Moreover, circ-TFF1 regulated FGFR1 expression by targeting miR-338-3p. Additionally, circ-TFF1 knockdown hampered tumorigenesis in vivo. Circ-TFF1 knockdown suppressed BC progression by regulating miR-338-3p/FGFR1 axis, providing a promising therapeutic target for BC.

Investigations on the Role of the MicroRNA-338-5p/Wnt Family Member 2B (WNT2B) Axis in Regulating the Pathogenesis of Nasopharyngeal Carcinoma (NPC)

Background

The involvement of microRNA-338-5p in modulating NPC pathogenesis is still largely unknown, and this study aimed to investigate this issue.

Methods

The expressions of cancer associated genes were determined by Real-Time qPCR and Western Blot, and cell apoptosis was determined by flow cytometer (FCM). CCK-8 assay and colony formation assay were respectively used to determine cell proliferation and colony formation abilities. Transwell assay was used to evaluate cell migration. The expression levels of Ki67 protein in mice tissues were measured by Immunohistochemistry (IHC) assay.

Results

The present study found that microRNA-338-5p suppressed NPC progression by degrading its downstream target, Wnt family member 2B (WNT2B). Specifically, microRNA-338-5p tended to be low-expressed in NPC tissues and cell lines, compared to the non-tumor nasopharyngeal mucosa tissues and normal nasopharyngeal cell line (NP69). Upregulation of microRNA-338-5p inhibited proliferation, mobility, and epithelial-mesenchymal transition (EMT) in NPC cells in vitro, while silencing of microRNA-338-5p had opposite effects. Consistently, microRNA-338-5p suppressed tumorigenesis of NPC cells in vivo. In addition, microRNA-338-5p targeted WNT2B for degradation and inhibition, and the inhibiting effects of microRNA-338-5p overexpression on NPC development were reversed by upregulating WNT2B.

Conclusions

Taken together, we concluded that microRNA-338-5p targeted WNT2B to hinder NPC development.

Molecular interactions of miR-338 during tumor progression and metastasis

Background

Cancer, as one of the main causes of human deaths, is currently a significant global health challenge. Since the majority of cancer-related deaths are associated with late diagnosis, it is necessary to develop minimally invasive early detection markers to manage and reduce mortality rates. MicroRNAs (miRNAs), as highly conserved non-coding RNAs, target the specific mRNAs which are involved in regulation of various fundamental cellular processes such as cell proliferation, death, and signaling pathways. MiRNAs can also be regulated by long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs). They are highly stable in body fluids and have tumor-specific expression profiles, which suggest their suitability as efficient non-invasive diagnostic and prognostic tumor markers. Aberrant expression of miR-338 has been widely reported in different cancers. It regulates cell proliferation, migration, angiogenesis, and apoptosis in tumor cells.

Main body

In the present review, we have summarized all miR-338 interactions with other non-coding RNAs (ncRNAs) and associated signaling pathways to clarify the role of miR-338 during tumor progression.

Conclusions

It was concluded that miR-338 mainly functions as a tumor suppressor in different cancers. There were also significant associations between miR-338 and other ncRNAs in tumor cells. Moreover, miR-338 has a pivotal role during tumor progression using the regulation of WNT, MAPK, and PI3K/AKT signaling pathways. This review highlights miR-338 as a pivotal ncRNA in biology of tumor cells.

Identification of circRNA-miRNA-mRNA Regulatory Network in Bladder Cancer by Integrated Analysis

INTRODUCTION

Bladder cancer (BC) is a common malignant tumor in the urinary system with high mortality and recurrence rates. This study sought to identify crucial circular RNAs (circRNAs) associated with BC.

METHODS

The mRNA, miRNA, and circRNA expression profiles of BC were downloaded from GEO database. The differentially expressed mRNAs (DEmRNAs), miRNAs (DEmiRNAs), and circRNAs (DEcircRNAs) were identified using bioinformatics method. Combining circRNA-miRNA pairs with miRNA-mRNA pairs, the competing endogenous RNA (ceRNA; DEcircRNA-DEmi-RNA-DEmRNA) regulatory network was constructed. Functional annotation of host gene of DEcircRNAs and DEmRNAs in ceRNA regulatory network were performed. qRT-PCR validation was performed.

RESULTS

A total of 4,003 DEmRNAs, 25 DEmiRNAs, and 119 DEcircRNAs were obtained. The ceRNA network contained 18 circRNA-miRNA pairs and 699 mi-RNA-mRNA pairs, including 17 circRNAs, 4 miRNAs, and 624 mRNAs. Functional annotation of DEmRNAs in ceRNA regulatory network revealed that these DEmRNAs were significantly enriched in glycerolipid metabolism, p53 signaling pathway, and oocyte meiosis. Except for hsa_circ_0028173, expression of the others in the qRT-PCR results was consistent with that in our integrated analysis, generally.

CONCLUSION

We speculate that hsa_circ_0008035/hsa-miR-107/MSRB3 and hsa_circ_0028173/hsa-miR-338-3p/TPX2/GATA3 interaction pairs may play a vital role in BC.

Role of microRNA/Epithelial-to-Mesenchymal Transition Axis in the Metastasis of Bladder Cancer

Bladder cancer (BC) is the 11th most common diagnosed cancer, and a number of factors including environmental and genetic ones participate in BC development. Metastasis of BC cells into neighboring and distant tissues significantly reduces overall survival of patients with this life-threatening disorder. Recently, studies have focused on revealing molecular pathways involved in metastasis of BC cells, and in this review, we focus on microRNAs (miRNAs) and their regulatory effect on epithelial-to-mesenchymal transition (EMT) mechanisms that can regulate metastasis. EMT is a vital process for migration of BC cells, and inhibition of this mechanism restricts invasion of BC cells. MiRNAs are endogenous non-coding RNAs with 19-24 nucleotides capable of regulating different cellular events, and EMT is one of them. In BC cells, miRNAs are able to both induce and/or inhibit EMT. For regulation of EMT, miRNAs affect different molecular pathways such as transforming growth factor-beta (TGF-β), Snail, Slug, ZEB1/2, CD44, NSBP1, which are, discussed in detail this review. Besides, miRNA/EMT axis can also be regulated by upstream mediators such as lncRNAs, circRNAs and targeted by diverse anti-tumor agents. These topics are also discussed here to reveal diverse molecular pathways involved in migration of BC cells and strategies to target them to develop effective therapeutics.

MiR-338 regulates NFATc1 expression and inhibits the proliferation and epithelial-mesenchymal transition of human non-small-cell lung cancer cells

BACKGROUND

It is well known that nuclear factor of activated T cells c1 (NFATc1) expression is closely associated with progression of many cancers. And we found that miR-338 could directly target the NFATc1. However, the precise mechanisms of miR-338 in non-small-cell lung cancer (NSCLC) have not been well clarified. Our study aimed to explore the interaction between NFATc1 and miR-338 in NSCLC.

METHODS

Quantitative RT-PCR was utilized to determine the expressions of NFATc1 and miR-338 in NSCLC tissues and cell lines. And the cell proliferation and epithelial-mesenchymal transition (EMT) were assessed to determine the functional roles of miR-338 and NFATc1 in NSCLC cells. NFATc1 expression was detected using quantitative RT-PCR and western blotting, respectively. Luciferase reporter assays were performed to validate NFATc1 as a target of miR-338 in NSCLC cells.

RESULTS

In this study, our results showed that NFATc1 expression was significantly up-regulated in NSCLC tissues and cell lines, and the miR-338 level was dramatically down-regulated. Moreover high NFATc1 expression was closely associated with low miR-338 level in NSCLC tissues. Moreover introduction of miR-338 significantly inhibited proliferation and EMT of NSCLC cells. Bioinformatics analysis predicted that the NFATc1 was a potential target gene of miR-338. We demonstrated that miR-338 could directly target NFATc1 by using luciferase reporter assay. Besides, knockdown of NFATc1 had the similar effects with miR-338 overexpression on NSCLC cells. Up-regulation of NFATc1 in NSCLC cells partially abolished the inhibitory effects of miR-338 mimic.

CONCLUSIONS

Overexpression of miR-338 inhibited cell proliferation and EMT of NSCLC cells by directly down-regulating NFATc1 expression.

Hsa_circ_0008945 promoted breast cancer progression by targeting miR-338-3p

PURPOSE

To detect the expression and function of circ_0008945 in breast cancer (BC) and to explore its potential molecular mechanisms in BC tumorigenesis.

MATERIALS AND METHODS

We measured expression levels of circ_0008945, miR-338-3p and homeobox A3 (HOXA3) in BC tissue specimens and cells using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). We examined the effects of all three genes on BC cell proliferation using Cell Counting Kit-8 (CCK-8) and colony formation assays. We also performed a Transwell assay to assess the migratory and invasive ability of treated BC cells. BC cell apoptosis was assessed using flow cytometric (FCM) analysis; interaction between miR-338-3p and circ_0008945 or HOXA3 was verified by dual-luciferase reporter assay as well as by ribonucleic-acid (RNA) pulldown. Finally, we used an in vivo tumor growth assay to assess the role of circ_0008945 overexpression in BC tumor growth.

RESULTS

We found that circ_0008945 expression was significantly increased in both BC tissue specimens and cells. This increase was correlated with poor prognosis in BC patients. Knockdown of circ_0008945 inhibited BC cell proliferation, migration and invasion while promoting BC cell apoptosis in vitro. Overexpression of circ_0008945 remarkably promoted BC tumor growth in vivo. Mechanistically, circ_0008945 acted as a miRNA sponge for miR-338-3p and inhibited its expression in BC cells. Moreover, miR-338-3p targeted and inhibited HOXA3.

CONCLUSION

We found that circ_0008945 acted as a BC oncogene by physically binding miR-338-3p, which further targeted and regulated HOXA3.