MiR-541-3p reverses cancer progression by directly targeting TGIF2 in non-small cell lung cancer

Host combats porcine reproductive and respiratory syndrome virus infection at non-coding RNAs level

Porcine reproductive and respiratory syndrome virus (PRRSV) poses a significant threat to the global swine industry. The emergence of new, highly virulent strains has precipitated recurrent outbreaks worldwide, underscoring the ongoing battle between host and virus. Thus, there is an imperative to formulate a more comprehensive and effective disease control strategy. Studies have shown that host non-coding RNA (ncRNA) is an important regulator of host - virus interactions in PRRSV infection. Hence, a thorough comprehension of the roles played by ncRNAs in PRRSV infection can augment our understanding of the pathogenic mechanisms underlying PRRSV infection. This review focuses on elucidating contemporary insights into the roles of host microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) in PRRSV infection, providing both theoretical foundations and fresh perspectives for ongoing research into the mechanisms driving PRRSV infection and its pathogenesis.

LINC02532 by Mediating miR-541-3p/HMGA1 Axis Exerts a Tumor Promoter in Breast cancer

The newly discovered LINC02532 is abnormally expressed in a variety of cancers and promotes cancer progression. The research proposed to discover the biological and molecular mechanisms of LINC02532 in breast cancer (BCa). In the resected BCa tissue samples and adjacent normal tissues, LINC02532, miR-541-3p, and High Mobility Group A1 (HMGA1) levels were determined. Cell function experiments were carried out on the premise of cell transfection with relevant plasmids. Based on that, the influence of LINC02532, miR-541-3p, and HMGA1 on MCF-7 cell activities (proliferation, migration, invasion, cell cycle, and apoptosis) was determined, as well as on EMT. Additionally, animal experiments were allowed to support cell experimental conclusions on LINC02532. Finally, the mechanistic network of LINC02532, miR-541-3p, and HMGA1 was identified. It was BCa tissues highly expressing LINC02532 and HMGA1, while lowly expressing miR-541-3p. Functionally, LINC02532 depletion repressed the activities and EMT process of MCF-7 cells. Silencing LINC02532 delayed tumor growth in mice. In terms of mechanism, LINC02532 mainly existed in the cytoplasm and could mediate HMGA1 expression by absorbing miR-541-3p. The findings offer new insights into the molecular mechanisms of LINC02532 in BCa and, more importantly, new strategies for the clinical treatment of BCa.

Dysregulation of Serum MicroRNA after Intracerebral Hemorrhage in Aged Mice

Stroke is one of the most common diseases that leads to brain injury and mortality in patients, and intracerebral hemorrhage (ICH) is the most devastating subtype of stroke. Though the prevalence of ICH increases with aging, the effect of aging on the pathophysiology of ICH remains largely understudied. Moreover, there is no effective treatment for ICH. Recent studies have demonstrated the potential of circulating microRNAs as non-invasive diagnostic and prognostic biomarkers in various pathological conditions. While many studies have identified microRNAs that play roles in the pathophysiology of brain injury, few demonstrated their functions and roles after ICH. Given this significant knowledge gap, the present study aims to identify microRNAs that could serve as potential biomarkers of ICH in the elderly. To this end, sham or ICH was induced in aged C57BL/6 mice (18–24 months), and 24 h post-ICH, serum microRNAs were isolated, and expressions were analyzed. We identified 28 significantly dysregulated microRNAs between ICH and sham groups, suggesting their potential to serve as blood biomarkers of acute ICH. Among those microRNAs, based on the current literature, miR-124-3p, miR-137-5p, miR-138-5p, miR-219a-2-3p, miR-135a-5p, miR-541-5p, and miR-770-3p may serve as the most promising blood biomarker candidates of ICH, warranting further investigation.

The function of miR-637 in non-small cell lung cancer progression and prognosis

BACKGROUND

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer with a high mortality rate and poor prognosis. miR-637 has been reported to regulate tumor progression and act as a prognosis biomarker of various cancers. Its functional role in NSCLC was investigated in this study.

METHODS

The expression level of miR-637 in NSCLC tissues and adjacent normal tissues of 123 NSCLC patients was analyzed by qRT-PCR. The association between miR-637 and clinical pathological features in the prognosis of patients was analyzed. Cell transfection was performed to overexpress or knockdown miR-637 in H1299 and HCC827. The proliferation, migration, and invasion of H1299 and HCC827 were evaluated by CCK8 and Transwell assay.

RESULTS

miR-637 expression was significantly decreased in NSCLC tissues and cell lines relative to normal tissues and cells. The survival rate of NSCLC patients with low miR-637 expression was lower than that of patients with high miR-637 expression. Additionally, miR-637 served as a tumor suppressor that inhibited cell proliferation, migration, and invasion of NSCLC.

CONCLUSION

Downregulation of miR-637 in NSCLC was associated with TNM stage and poor prognosis of patients and served as a tumor suppressor in NSCLC. These results provide a potential strategy to control NSCLC.

miR-541-3p Promoted Porcine Reproductive and Respiratory Syndrome Virus 2 (PRRSV-2) Replication by Targeting Interferon Regulatory Factor 7

Porcine reproductive and respiratory syndrome (PRRS) is a disease caused by PRRS virus (PRRSV), which seriously harms the pig industry. Revealing the mechanism by which PRRSV inhibits immune response will help prevent and control PRRS. Here, we found that PRRSV-2 may hijack host miR-541-3p to inhibit host innate immune response. Firstly, this work showed that miR-541-3p mimics could facilitate the replication of PRRSV-2 and the results of the quantitative real time polymerase chain reaction (qRT-PCR) showed that PRRSV-2 could up-regulate the expression of miR-541-3p in MARC-145 cells. Since previous studies have shown that type I interferon could effectively inhibit the replication of PRRSV-2, the present work explored whether miR-541-3p regulated the expression of type I interferon and found that miR-541-3p could negatively regulate the transcription of type I interferon by targeting interferon regulatory factor 7 (IRF7). More importantly, PRRSV-2 infection could down-regulate the expression of IRF7 and over-expression of IRF7 could down-regulate the replication of PRRSV-2 in MARC-145 cells. In conclusion, PRRSV-2 infection up-regulated the expression of miR-541-3p to promote its replication in MARC-145 cells, since miR-541-3p can negatively regulate the transcription of type I interferon by targeting IRF7.

Circular RNA circCPA4 promotes tumorigenesis by regulating miR-214-3p/TGIF2 in lung cancer

Background

Lung cancer is the most prevalent malignancy in adults. Circular RNA (circRNA) circCPA4 (hsa_circ_0082374) is highly expressed in non‐small cell lung cancer (NSCLC). The purpose of this study was to explore the role and mechanism of circCPA4 in lung cancer.

Methods

CircCPA4, linear CPA4, TGF‐β‐induced factor homeobox 2 (TGIF2), and microRNA‐214‐3p (miR‐214‐3p) levels were measured by real‐time quantitative polymerase chain reaction (RT‐qPCR). The protein levels of TGIF2, Beclin1, and p62 were assessed by western blot assay. Colony numbers, migration, invasion, apoptosis, and cell cycle progression were examined by colony formation, wound‐healing, transwell, and flow cytometry assays, respectively. The binding relationship between miR‐214‐3p and circCPA4 or TGIF2 was predicted by StarBase or TargetScan and then verified by a dual‐luciferase reporter, RNA immunoprecipitation (RIP), and RNA pulldown assays. The biological role of circCPA4 on lung tumor growth was assessed by a xenograft tumor model in vivo, and TGIF2 and ki‐67 expression was assessed by immunohistochemistry.

Results

We determined that CircCPA4 and TGIF2 were increased, and miR‐214‐3p was decreased in lung cancer tissues and cells. Functionally, circCPA4 knockdown could suppress colony formation, migration, invasion, cell cycle progression, and expedite apoptosis of lung cancer cells in vitro. Mechanically, circCPA4 could regulate TGIF2 expression by sponging miR‐214‐3p. In addition, circCPA4 deficiency inhibited the tumor growth in lung cancer in the mouse model.

Conclusions

CircCPA4 could act as a sponge of miR‐214‐3p to upregulate TGIF2 expression, thereby promoting the progression of lung cancer cells. These findings suggested underlying therapeutic targets for the treatment of lung cancer.

Genetic variations in 3´UTRs of SMUG1 and NEIL2 genes modulate breast cancer risk, survival and therapy response

Breast cancer (BC) is the most frequent malignancy in women accounting for approximately 2 million new cases worldwide annually. Several genetic, epigenetic and environmental factors are known to be involved in BC development and progression, including alterations in post-transcriptional gene regulation mediated by microRNAs (miRNAs). Single nucleotide polymorphisms (SNPs) located in miRNA binding sites (miRSNPs) in 3'-untranslated (UTR) regions of target genes may affect miRNA-binding affinity and consequently modulate gene expression. We have previously reported a significant association of miRSNPs in the SMUG1 and NEIL2 genes with overall survival in colorectal cancer patients. SMUG1 and NEIL2 are DNA glycosylases involved in base excision DNA repair (BER). Assuming that certain genetic traits are common for solid tumours, we have investigated wherever variations in SMUG1 and NEIL2 genes display an association with BC risk, prognosis, and therapy response in a group of 673 BC patients and 675 healthy female controls. Patients with TC genotype of NEIL2 rs6997097 and receiving only hormonal therapy displayed markedly shorter overall survival (OS) (HR=4.15, 95% CI=1.7-10.16, P= 0.002) and disease-free survival (DFS) (HR=2.56, 95% CI=1.5-5.7, P= 0.02). Our results suggest that regulation of base excision repair glycosylases operated by miRNAs may modulate the prognosis of hormonally treated BC.

Nanoceria, alone or in combination with cigarette-smoke condensate, induce transforming and epigenetic cancer-like features in vitro

Aim: To detect cell transformation effects of nanoceria after long-term exposure (up to 6 weeks) and to determine their potential interactions with cigarette smoke condensate, as a model of environmental carcinogenic pollutant. Materials & methods: Human bronchial epithelial BEAS-2 cells were used to determine transformation effects (invasion and tumorspheres induction), as well as changes in the expression of a battery of miRNAs related to the carcinogenesis process. Results: Nanoceria- and co-exposed cells exhibit cell transforming potential, with significantly increased invasion and tumorsphere formation abilities. Likewise, these exposures produced a high impact on the battery of miRNAs used. Conclusion: Nanoceria exposure induces cell-transformation and shows a positive interaction with the cell-transforming effects of cigarette smoke condensate. Besides, cerium dioxide nanoparticles and the co-exposure produced potential toxicity at the transcriptome level, which is related to tumorigenesis.

miR-541-3p enhances the radiosensitivity of prostate cancer cells by inhibiting HSP27 expression and downregulating β-catenin

Heat shock protein 27 (HSP27), a regulator of cell survival, can enhance the resistance of cancer cells to radiotherapy. As microRNA-541-3p (miR-541-3p) was recently predicted to be a putative upstream modulator of HSP27, the present study was designed to investigate the function and mechanism underlying how miR-541-3p modulates the radiosensitivity of prostate cancer (PCa) cells by regulating HSP27. Through quantitative PCR, miR-541-3p was determined to be poorly expressed in PCa tissues relative to normal controls, whereas its expression was enhanced after radiotherapy. Consistently, miR-541-3p expression levels in PCa cells were elevated after radiation. Cell viability and proliferation and apoptosis under radiation were subsequently evaluated in response to loss-of-function of miR-541-3p. It was found that inhibition of miR-541-3p facilitated the viability and proliferation of PCa cells and promoted their apoptosis post radiation, hence reducing the radiosensitivity of LNCaP cells. Dual-luciferase reporter assay identified that miR-541-3p negatively regulated the HSP27 mRNA expression by targeting its 3'-UTR. Meanwhile, miR-541-3p overexpression inhibited the β-catenin expression by targeting HSP27. Furthermore, HSP27 or β-catenin overexpression was noted to significantly reverse the miR-541-3p-mediated changes in the biological functions of PCa cells post radiation, suggesting that HSP27-dependent activation of β-catenin might be the mechanism responsible for the promotive effect of miR-541-3p on radiosensitivity. Collectively, this study suggests that miR-541-3p specifically inhibits the HSP27 expression and downregulates β-catenin, thereby enhancing the radiosensitivity of PCa cells. Our findings highlight the underlying mechanism of the miR-541-3p/HSP27/Wnt/β-catenin axis regarding radiotherapy for PCa.

CircIL4R facilitates the tumorigenesis and inhibits ferroptosis in hepatocellular carcinoma by regulating the miR-541-3p/GPX4 axis

Ferroptosis is a specific iron-dependent cell death form that can induce the production of lipid peroxide, but the roles of circular RNAs (circRNAs) in ferroptosis are completely unaware. Circ-interleukin-4 receptor (circIL4R) was reported to express highly in hepatocellular carcinoma (HCC). This study focused on the function of circIL4R dysregulation in tumor progression and ferroptosis of HCC, as well as its molecular mechanism. The quantitative real-time polymerase chain reaction was implemented for measuring RNA expression. Cell proliferation and survival were evaluated using 3-(4,5-dimethylthiazol-2-y1)-2,5-diphenyl tetrazolium bromide. Apoptotic cells were detected via flow cytometry. The quantification of protein expression was executed through western blotting analysis. The target binding was assessed via the dual-luciferase reporter, RNA immunoprecipitation, and RNA pull-down assays. The experiment in vivo was performed using a xenograft model. CircIL4R was abnormally overexpressed in HCC tissues and cells. CircIL4R knockdown impeded oncogenesis and expedited ferroptosis of HCC cells. CircIL4R could directly sponge microRNA-541-3p (miR-541-3p) and miR-541-3p inhibition mitigated the effects of circIL4R knockdown on HCC cells. CircIL4R acted as a miR-541-3p sponge to regulate its target glutathione peroxidase 4 (GPX4). GPX4 upregulation relieved the miR-541-3p-induced tumor inhibition and ferroptosis aggravation. CircIL4R played an oncogenic role in HCC via the miR-541-3p/GPX4 axis in vivo. Our data suggested that circIL4R served for a tumor promoter and ferroptosis inhibitor in HCC by the miR-541-3p/GPX4 network.

miR-541 serves as a prognostic biomarker of osteosarcoma and its regulatory effect on tumor cell proliferation, migration and invasion by targeting TGIF2

Background

Several studies reported the dysregulation of miR-541 in the progression of some human malignancies. Osteosarcoma (OS) is one of the most common primary malignant bone tumors. This study aimed to assess the expression and clinical significance of miR-541 in OS patients and explore the biological function of miR-541 in tumor progression.

Methods

Expression of miR-541 was detected by quantitative real-time PCR, and its prognostic value was evaluated using Kaplan-Meier survival analysis. The biological function of miR-541 was examined by analyzing its effects on OS cell proliferation, migration and invasion. Additionally, the underlying potential target of miR-541 was predicated and analyzed.

Results

The expression of miR-541 was significantly decreased in OS tissues and cell lines. The deregulated expression of miR-541 in tumor tissues was associated with the overall survival of OS patients and was a potential independent prognostic indicator. In OS cells, the overexpression of miR-541 could inhibit cell proliferation, migration and invasion. The luciferase activity results indicated that TGIF2 was a potential target of miR-541.

Conclusion

The results of this study revealed that the decreased miR-541 expression in OS patients may serve as a prognostic biomarker, and that the overexpression of miR-541 in OS cells results in inhibited cell proliferation, migration and invasion, indicating the potential of miR-541 as a therapeutic target in OS treatment.

Long Noncoding RNA FAM83H-AS1 Modulates SpA-Inhibited Osteogenic Differentiation in Human Bone Mesenchymal Stem Cells

Osteomyelitis, an infection of the bone and bone marrow, imposes a heavy burden on public health care systems owing to its progressive bone destruction and sequestration. Human bone mesenchymal stem cells (hBMSCs) play a key role in the process of bone formation, and mounting evidence has confirmed that long noncoding RNAs (lncRNAs) are involved in hBMSC osteogenic differentiation. Nevertheless, the exact function and molecular mechanism of lncRNAs in osteogenic differentiation during osteomyelitis development remain to be explored. In this study, hBMSCs were treated with staphylococcal protein A (SpA) during osteogenic differentiation induction to mimic osteomyelitis in vitro The results of lncRNA microarray analysis revealed that FAM83H-AS1 presented the lowest expression among the significantly downregulated lncRNAs. Functionally, ectopic expression of FAM83H-AS1 contributed to osteogenic differentiation of SpA-induced hBMSCs. Additionally, our findings revealed that FAM83H-AS1 negatively regulated microRNA 541-3p (miR-541-3p), and WNT3A was validated as a target gene of miR-541-3p. Mechanically, FAM83H-AS1 elevated WNT3A expression by competitively binding with miR-541-3p. Lastly, it was demonstrated that FAM83H-AS1/miR-541-3p/WNT3A ameliorated SpA-mediated inhibition of the osteogenic differentiation of hBMSCs, which provided a novel therapeutic strategy for patients with osteomyelitis.

Prognostic role of 14q32.31 miRNA cluster in various carcinomas: a systematic review and meta-analysis

Deregulated miR-379/miR-656 cluster expression is considered as important for carcinogenesis and can be used as a potential prognostic marker. Hence, the meta-analysis was conducted to test the utility of miR-379/miR-656 cluster as a prognostic marker in various cancers. A literature search was performed using Web of Science, PubMed and Cochrane Library to obtain relevant studies and were subjected to various subgroup and bioinformatics analyses. Selected twenty-three studies contained 13 cancer types comprising of 3294 patients from 7 nations. Univariate and multivariate data showed an association of high expression of miRNAs with the poor prognosis of cancer patients (p < 0.001). The subgroup analysis showed that lung cancer, breast cancer and papillary renal cell carcinoma (p < 0.001) have a negative association with the survival of patients. Our study is the first meta-analysis showing the association of miR-379/miR-656 cluster expression and overall survival, suggesting its potential as a prognostic indicator in multiple cancers.

TGIF2 promotes the progression of lung adenocarcinoma by bridging EGFR/RAS/ERK signaling to cancer cell stemness

TGF-β-induced factor homeobox 2 (TGIF2) is a transcription regulator that plays essential roles in the regulation of development and cell fate decisions. Aberrant expression of TGIF family proteins has been observed in several cancers, including ovarian, esophageal, and colorectal cancers. Here, we report that TGIF2 mediates the EGFR-RAS-ERK signaling pathway to enhance the stemness of lung adenocarcinoma (LUAD) cells and, therefore, promote the progression and metastasis of LUAD. We found that high TGIF2 expression was closely correlated with tumor growth, lymph node metastasis, and survival of patients with LUAD. Mice bearing TGIF2-silenced H1299 xenografts developed smaller tumors and fewer lung metastases. Importantly, silencing TGIF2 decreased the cancer stem cell (CSC)-like properties in A549 and H1299 cells. Furthermore, we identified that TGIF2 binding to the OCT4 promoter promotes its expression. In both LUAD cells and in vivo LUAD mouse models, we revealed that EGFR-RAS-ERK signaling phosphorylated TGIF2 and increased its stability, which was important for TGIF2-promoted LUAD stemness since phosphorylation-deficient TGIF2 mutants lost these functions. Thus, our study revealed that an important factor, TGIF2, bridges EGFR signaling to the CSC characteristics of LUAD cells, which can be utilized as an effective target for LUAD therapy.

Polycomb complex mediated epigenetic reprogramming alters TGF-β signaling via a novel EZH2/miR-490/TGIF2 axis thereby inducing migration and EMT potential in glioblastomas

Recent advancement in understanding cancer etiology has highlighted epigenetic deregulation as an important phenomenon leading to poor prognosis in glioblastoma (GBM). Polycomb repressive complex 2 (PRC2) is one such important epigenetic modifier reportedly altered in GBM. However, its defined mechanism in tumorigenesis still remains elusive. In present study, we analyzed our in-house ChIPseq data for H3k27me3 modified miRNAs and identified miR-490-3p to be the most common target in GBM with significantly downregulated expression in glioma patients in both TCGA and GBM patient cohort. Our functional analysis delineates for the first time, a central role of PRC2 catalytic unit EZH2 in directly regulating expression of this miRNA and its host gene CHRM2 in GBM. In accordance, cell line treatment with EZH2 siRNA and 5-azacytidine also confirmed its coregulation by CpG and histone methylation based epigenetic mechanisms. Furthermore, induced overexpression of miR-490-3p in GBM cell lines significantly inhibited key hallmarks including cellular proliferation, colony formation and spheroid formation, as well as epithelial-to-mesenchymal transition (EMT), with downregulation of multiple EMT transcription factors and promigratory genes (MMP9, CCL5, PIK3R1, ICAM1, ADAM17 and NOTCH1). We also for the first time report TGFBR1 and TGIF2 as two direct downstream effector targets of miR-490-3p that are also deregulated in GBM. TGIF2, a novel target, was shown to promote migration and EMT that could partially be rescued by miR-490-3p overexpression. Overall, this stands as a first study that provides a direct link between epigenetic modulator EZH2 and oncogenic TGF-β signaling involving novel miR-490-3p/TGIF2/TGFBR1 axis, that being targetable might be promising in developing new therapeutic intervention strategies for GBM.

MALAT1 promotes proliferation, migration, and invasion of MG63 cells by upregulation of TGIF2 via negatively regulating miR-129

Purpose

This article aimed to investigate the mechanism by which MALAT1 and miR-129 affected the development of osteosarcoma.

Methods

Tumor tissues and adjacent tissues of 23 osteosarcoma patients were collected. Normal osteoblasts hFOB1.19 and osteosarcoma cells MG63 were cultured. MG63 cells were transfected and grouped: si-negative control (NC) group, si-MALAT1 group, miR-129 NC group, miR-129 mimics group, p-Empty vector group, p-MALAT1 group, p-MALAT1+ miR-129 mimics group, and p-MALAT1+ si-TGIF2 group. Luciferase reporter assay, Cell Counting Kit-8 assay, Transwell assay, quantitative reverse transcription PCR, Western blot, and Pearson correlation analysis were performed.

Results

MALAT1 expression in tumor tissues and MG63 cells was increased (P<0.01). High MALAT1 expression predicted poor prognosis of osteosarcoma patients. MG63 cells of si-MALAT1 group exhibited much lower cell viability, migration, and invasive cell numbers when compared with si-NC group (P<0.01). For MG63 cells of miR-129 mimics group, they had markedly lower cell viability, migration, and invasive cell numbers than miR-129 NC group (P<0.01). miR-129 was targetedly and negatively regulated by MALAT1. TGIF2, which was targetedly and negatively regulated by miR-129, was overexpressed in tumor tissues and MG63 cells (P<0.01). miR-129 overexpresison and TGIF2 downregulation significantly reversed the enhanced cell viability, migration, and invasion induced by MALAT1 (P<0.01).

Conclusion

MALAT1 promotes TGIF2 expression through negative regulation of miR-129, which further promotes the proliferation, migration, and invasion of MG63 cells.

miR-34 inhibits growth and promotes apoptosis of osteosarcoma in nude mice through targetly regulating TGIF2 expression

miR-34 was reported to be involved in multiple tumors occurrence and development. The aim of the present study was to explore the impact of miR-34 on osteosarcoma and related mechanisms. Tumor tissues and non-tumor tissues of 34 patients with osteosarcoma were collected. qRT-PCR detection revealed that miR-34 was significantly down-regulated in tumor tissues (P<0.05). hFOB 1.19 and MG-63 cells were cultured. qRT-PCR detection showed that miR-34 was also significantly down-regulated in MG-63 cells (P<0.05). After transfection by miR-34 mimics, MG-63 cells proliferation in nude mice was significantly impaired (P<0.05), and percentage of apoptosis as well as caspase-3 positive cells proportion of osteosarcoma tissue in nude mice was markly increased (P<0.05). Western blot and immunofluorescence results also demonstrated that TGIF2 relative expression and TGIF2 positive cells proportion were both dramatically decreased (P<0.05). By luciferase reporter assay, we found that TGIF2 was the target gene of miR-34. After transfected by TGIF2 overexpression vector or co-transfected by miR-34 mimics and TGIF2 overexpression vector, we observed that, compared with blank group, tumor volume was significantly increased and apoptotic cells as well as caspase-3 positive cells proportion was obviously decreased in TGIF2 group (P<0.05), while no significant difference was found in these indicators between blank group and TGIF2 + mimics group. We concluded that miR-34 inhibited growth and promoted apoptosis of osteosarcoma in nude mice through targetting regulated TGIF2 expression.

miR-541 suppresses proliferation and invasion of squamous cell lung carcinoma cell lines via directly targeting high-mobility group AT-hook 2

An increasing number of studies have demonstrated that micro-ribonucleic acids (miRNAs) are important tumor suppressors during carcinogenesis. However, the function of miRNA-541 (miR-541) in malignancies, especially lung cancer, has not been widely reported. In this study, miR-541 expression was significantly decreased in squamous cell lung carcinoma (SCLC) cancerous tissue and SCLC cell lines. To analyze miR-541 function in SCLC, we overexpressed miR-541 in SCLC cell lines (SK-MES-1 and H226). According to the CCK8, wound scratch, and transwell invasion assay results, miR-541 overexpression significantly inhibited SCLC cell proliferation, migration, and invasion ability. Next, using RT-PCR, Western blotting, immunocytochemistry, and luciferase assays, HMGA2 was identified, for the first time, as a direct regulatory target of miR-541 in SK-MES-1 and H226 cells. Furthermore, upregulating HMGA2 expression significantly alleviated the suppressive effects of miR-541 on SK-MES-1 and H226 cell proliferation, migration, and invasion. In summary, our study revealed that miR-541 inhibited SCLC proliferation and invasion by directly targeting HMGA2.

MiR-129-5p inhibits glioma cell progression in vitro and in vivo by targeting TGIF2

This study purposed to explore the correlation between miR-129-5p and TGIF2 and their impacts on glioma cell progression. Differentially expressed miRNA was screened through microarray analysis. MiR-129-5p expression levels in glioma tissues and cells were measured by qRT-PCR. CCK-8 assay, flow cytometer, transwell assay and wound-healing assay were employed to detect cell proliferation, apoptosis and cycle, invasiveness and migration, respectively. Dual-luciferase reporting assay was performed to confirm the targeted relationship between miR-129-5p and TGIF2. The effects of TGIF2 expression on cell biological functions were also investigated using the indicated methods. Tumour xenograft was applied to explore the impact of miR-129-5p on tumorigenesis in vivo. MiR-129-5p expression was down-regulated in both glioma tissues and glioma cells, while TGIF2 expression was aberrantly higher than normal level. Dual-luciferase reporter assay validated the targeting relation between miR-129-5p and TGIF2. Overexpression of miR-129-5p or down-regulation of TGIF2 inhibited the proliferation, invasion and migration capacity of glioma cells U87 and U251, and meanwhile blocked the cell cycle as well as induced cell apoptosis. MiR-129-5p overexpression repressed the tumour development in vivo. MiR-129-5p and TGIF2 had opposite biological functions in glioma cells. MiR-129-5p could inhibit glioma cell progression by targeting TGIF2, shining light for the development of target treatment for glioma.

A comprehensive analysis of the predicted targets of miR-642b-3p associated with the long non-coding RNA HOXA11-AS in NSCLC cells

Long non-coding RNA HOXA11 antisense RNA (HOXA11-AS) has been previously reported to be involved in the tumorigenesis and progression of ovarian cancer and glioma. However, the function of HOXA11-AS in lung cancer remains unclear. Following the knockdown of HOXA11-AS in A549 cells, a microarray analysis was performed in order to detect the differences in microRNA (miRNA/miR) profiles. Subsequently, miR-642b-3p was selected for further analysis. Four miRNA target prediction algorithms were used to identify potential target genes of miR-642b-3p. Bioinformatics analyses, including Gene Ontology (GO), Kyoto Encyclopaedia of Genes and Genomes, protein-protein interactions (PPIs) and network analysis, were performed to investigate the potential functions, pathways and networks of the target genes. Furthermore, the differential expression of miR-642b-3p and its target genes between normal lung and non-small cell lung cancer (NSCLC) tissues was verified using The Cancer Genome Atlas (TCGA) database. Six target genes [zinc finger protein 350, heterogeneous nuclear ribonucleoprotein U, high mobility group box 1, phosphodiesterase 4D (PDE4D), synaptotagmin binding cytoplasmic RNA interacting protein and basic helix-loop-helix family member B9] of miR-642b-3p were predicted using all 4 algorithms. It was revealed that miR-642b-3p was overexpressed in adenocarcinoma and squamous cell carcinoma tissues compared with non-cancerous lung tissues based on the TCGA database. From the 6 target genes, PDE4D was downregulated in lung adenocarcinoma and squamous cell carcinoma tissues, and a weak negative correlation between HOXA11-AS and PDE4D was identified. The area under the curve of PDE4D was 0.905 [95% confidence interval (CI), 0.879–0.931] for patients with lung adenocarcinoma and 0.665 (95% CI, 0.606–0.725) for patients with squamous cell carcinoma. Additionally, GO analysis of the target genes revealed that miR-642b-3p was specifically involved in complex cellular pathways. The target gene RAN binding protein 2 possessed the highest degree of interactions in the PPI network (degree=40). It was hypothesized that HOXA11-AS may have a function in NSCLC by regulating the expression of miR-642b-3p and PDE4D, which laid the foundation for the further elucidation of the potential molecular mechanisms of NSCLC.

Overexpression of microRNA-506-3p aggravates the injury of vascular endothelial cells in patients with hypertension by downregulating Beclin1 expression

The aim of the present study was to measure the expression of microRNA (miRNA)-506-3p in the peripheral blood of patients with hypertension and to determine the biological functions and mechanisms of action of miR-506-3p. A total of 61 patients with primary hypertension were included in the present study. Peripheral blood was collected from all patients, as well as 31 healthy subjects who were included in a control group. The expression of miR-506-3p in peripheral blood was determined by reverse transcription-quantitative polymerase chain reaction. Human umbilical vein endothelial cells (HUVECs) were transfected with miR-506-3p mimics or miR-506-3p inhibitor. The proliferation and migration of HUVECs were determined using cell-counting kit 8 and Transwell assays, respectively. The cell cycle and apoptosis of HUVECs were detected by flow cytometry. The expression of Beclin1 (BECN1) protein, a potential target of miR-506-3p, was measured using western blotting. A dual-luciferase reporter assay was performed to determine the interaction between BECN1 and miR-506-3p. It was demonstrated that miR-506-3p expression in the peripheral blood of patients with patients was upregulated and dependent on the severity of hypertension. miR-506-3p overexpression inhibited the proliferation and migration of HUVECs. In addition, miR-506-3p inhibited the transition from the G1 phase to the S-phase in HUVECs. Overexpression of miR-506-3p promoted the apoptosis of HUVECs. Notably, miR-506-3p downregulated the expression of BECN1 by directly binding to its 3′-untranslated region. The present study demonstrated that miR-506-3p expression is elevated in the peripheral blood of patients with hypertension and is associated with the severity of hypertension. By downregulating BECN1 expression, miR-506-3p aggravates injury in vascular endothelial cells by inhibiting the proliferation and migration of HUVECs, as well as promoting their apoptosis.

Identification of expression quantitative trait loci (eQTLs) in human peripheral blood mononuclear cells (PBMCs) and shared with liver and brain

PBMCs are essential for immunity and involved in various diseases. To identify genetic variations contributing to PBMCs transcriptome-wide gene expression, we performed a genome-wide eQTL analysis by using genome-wide SNPs data and transcriptome-wide mRNA expression data. To assess whether there are common regulation patterns shared among different tissues/organs, public datasets were utilized to identify common eQTLs shared with PBMCs in lymphoblastoid, monocytes, liver, and brain. Allelic expression imbalance (AEI) assay was employed to validate representative eQTLs identified. We identified 443 cis- and 2386 trans-eSNPs (FDR <0.05), which regulated 128 and 635 target genes, respectively. A transcriptome-wide expression regulation network was constructed, highlighting the importance of 28 pleiotropic eSNPs and 18 dually (cis- and trans-) regulated genes. Three genes, that is, TIPRL, HSPB8, and EGLN3, were commonly regulated by hundreds of eSNPs and constituted a very complex interaction network. Strikingly, the missense SNP rs371513 trans- regulated 25 target genes, which were functionally related to poly(A) RNA binding. Among 8904 eQTLs (P < 0.001) identified herein in PBMCs, a minority (163) was overlapped with lymphoblastoid, monocytes, liver, and/or brain. Besides, two cis-eSNPs in PBMC were confirmed by AEI. The present results demonstrated a comprehensive expression regulation network for human PBMCs and may provide novel insights into the pathogenesis of immunological diseases related to PBMCs.

Profound changes in miRNA expression during cancer initiation by aflatoxin B1 and their abrogation by the chemopreventive triterpenoid CDDO-Im

Aflatoxin B₁ (AFB₁ ) is a potent human and animal hepatocarcinogen. To investigate the effects of aflatoxin on miRNA expression during the initiation phase of carcinogenesis, next-generation sequencing was used to analyze liver tissues from F344 rats exposed to 200 μg/kg per day AFB₁ for 4 week. A panel of miRNAs was identified that was upregulated with AFB₁ treatment compared to controls: rno-miR-434-3p, rno-miR-411-5p, rno-miR-221-3p, rno-miR-127-3p, rno-miR-205, rno-miR-429, rno-miR-34a-5p, rno-miR-181c-3p, rno-miR-200b-3p, and rno-miR-541-5p. Analysis of rat livers exposed to AFB₁ plus the chemopreventive triterpenoid CDDO-Im revealed a striking abrogation of this upregulation. These changes were validated by real-time PCR. We also explored the temporal variation in expression of the candidate miRNAs during the 4-week dosing period. Most of the candidate miRNAs were upregulated at week 1 and increased for the duration of AFB₁ dosing over the 4-week period. Treatment with CDDO-Im ameliorated these effects at all time points. All candidate miRNAs were detectable in serum from aflatoxin treated animals; however, there was no significant difference in expression for 7 of the 11 miRNAs examined. Exposure to AFB₁ upregulated miR-122-5p (fivefold), 34a-5p (13-fold), and 181c-3p (170-fold) compared with controls. The findings from this study give insight into epigenetic changes induced by aflatoxin taking place during the initial step of carcinogenesis.

Epithelial-to-Mesenchymal Transition and MicroRNAs in Lung Cancer

Despite major advances, non-small cell lung cancer (NSCLC) remains the major cause of cancer-related death in developed countries. Metastasis and drug resistance are the main factors contributing to relapse and death. Epithelial-to-mesenchymal transition (EMT) is a complex molecular and cellular process involved in tissue remodelling that was extensively studied as an actor of tumour progression, metastasis and drug resistance in many cancer types and in lung cancers. Here we described with an emphasis on NSCLC how the changes in signalling pathways, transcription factors expression or microRNAs that occur in cancer promote EMT. Understanding the biology of EMT will help to define reversing process and treatment strategies. We will see that this complex mechanism is related to inflammation, cell mobility and stem cell features and that it is a dynamic process. The existence of intermediate phenotypes and tumour heterogeneity may be debated in the literature concerning EMT markers, EMT signatures and clinical consequences in NSCLC. However, given the role of EMT in metastasis and in drug resistance the development of EMT inhibitors is an interesting approach to counteract tumour progression and drug resistance. This review describes EMT involvement in cancer with an emphasis on NSCLC and microRNA regulation.

DLK1-DIO3 imprinted locus deregulation in development, respiratory disease, and cancer

INTRODUCTION

The imprinted DLK1-DIO3 locus at 14q32.1-32.31 holds biological significance in fetal development, whereby imprinting errors are causal to developmental disorders. Emerging evidence has implicated this locus in other diseases including cancer, highlighting the biological parallels between fetal organ and tumour development. Areas covered: Controlled regulation of gene expression from the imprinted DLK1-DIO3 locus at 14q32.1-32.31 is crucial for proper fetal development. Deregulation of locus gene expression due to imprinting errors has been mechanistically linked to the developmental disorders Kagami-Ogata Syndrome and Temple Syndrome. In adult tissues, deregulation of locus genes has been associated with multiple malignancies although the causal genetic mechanisms remain largely uncharacterised. Here, we summarize the genetic mechanisms underlying the developmental disorders that arise as a result of improper locus imprinting and the resulting developmental phenotypes, emphasizing both the coding and noncoding components of the locus. We further highlight biological parallels common to both fetal development and disease, with a specific focus on lung development, respiratory disease, and lung cancer. Expert commentary: Many commonalities between respiratory and developmental defects have emerged with respect to the 14q32 locus, emphasizing the importance of studying the effects of imprinting on gene regulation patterns at this locus in both biological settings.

Meta-analysis of miRNA expression profiles for prostate cancer recurrence following radical prostatectomy

BACKGROUND

Prostate cancer (PCa) is a leading reason of death in men and the most diagnosed malignancies in the western countries at the present time. After radical prostatectomy (RP), nearly 30% of men develop clinical recurrence with high serum prostate-specific antigen levels. An important challenge in PCa research is to identify effective predictors of tumor recurrence. The molecular alterations in microRNAs are associated with PCa initiation and progression. Several miRNA microarray studies have been conducted in recurrence PCa, but the results vary among different studies.

METHODS

We conducted a meta-analysis of 6 available miRNA expression datasets to identify a panel of co-deregulated miRNA genes and overlapping biological processes. The meta-analysis was performed using the 'MetaDE' package, based on combined P-value approaches (adaptive weight and Fisher's methods), in R version 3.3.1.

RESULTS

Meta-analysis of six miRNA datasets revealed miR-125A, miR-199A-3P, miR-28-5P, miR-301B, miR-324-5P, miR-361-5P, miR-363*, miR-449A, miR-484, miR-498, miR-579, miR-637, miR-720, miR-874 and miR-98 are commonly upregulated miRNA genes, while miR-1, miR-133A, miR-133B, miR-137, miR-221, miR-340, miR-370, miR-449B, miR-489, miR-492, miR-496, miR-541, miR-572, miR-583, miR-606, miR-624, miR-636, miR-639, miR-661, miR-760, miR-890, and miR-939 are commonly downregulated miRNA genes in recurrent PCa samples in comparison to non-recurrent PCa samples. The network-based analysis showed that some of these miRNAs have an established prognostic significance in other cancers and can be actively involved in tumor growth. Gene ontology enrichment revealed many target genes of co-deregulated miRNAs are involved in "regulation of epithelial cell proliferation" and "tissue morphogenesis". Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that these miRNAs regulate cancer pathways. The PPI hub proteins analysis identified CTNNB1 as the most highly ranked hub protein. Besides, common pathway analysis showed that TCF3, MAX, MYC, CYP26A1, and SREBF1 significantly interact with those DE miRNA genes. The identified genes have been known as tumor suppressors and biomarkers which are closely related to several cancer types, such as colorectal cancer, breast cancer, PCa, gastric, and hepatocellular carcinomas. Additionally, it was shown that the combination of DE miRNAs can assist in the more specific detection of the PCa and prediction of biochemical recurrence (BCR).

CONCLUSION

We found that the identified miRNAs through meta-analysis are candidate predictive markers for recurrent PCa after radical prostatectomy.

Targeted Expression of miR-7 Operated by TTF-1 Promoter Inhibited the Growth of Human Lung Cancer through the NDUFA4 Pathway

Targeted expression of gene technique is an important therapeutic strategy for lung cancer. MicroRNA-7 has been well documented as a promising tumor suppressor but never been test in specific gene-promoter-targeted expression in cancer gene therapy. Here, we first evaluated the efficacy of miR-7 expression operated by the promoter of TTF-1, a lineage-specific oncogene in lung cancer, in vitro using an eukaryotic vector of TTF-1-promoter-operated expression of miR-7 (termed as p-T-miR-7). Interestingly, using a nude mice model, the growth and metastasis of human lung cancer cells in vivo were significantly reduced in remote hypodermic injection of the p-T-miR-7 group, accompanied by increased expression of miR-7 and reduced transduction of the Akt and Erk pathway in situ. Mechanism aspect, global gene expression analysis showed that downregulation of NDUFA4, a novel target of miR-7, contributed to the effects of miR-7 expression operated by TTF-1 promoter on the growth and metastasis of human lung cancer cells, as well as altered transduction of the Akt and Erk pathway. Finally, there was no significant difference in weight or histopathology of other organs. These data provided a basis for development of novel modality of miRNA-based targeted expression therapy against clinical lung cancer.