MiR-130b inhibits proliferation and induces apoptosis of gastric cancer cells via CYLD

Evaluation of miR-130b-3p and miR-375 levels and telomere length with telomerase activity in prostate cancer

Prostate cancer (PC) is the most frequent cancer in males, as well as the second highest cause of cancer-related deaths in men. Differences in expression levels of miRNAs were linked with prostat cancer pathogenesis. qPCR was used to evaluate the expression of miR-130b-3p and miR-375 in Benign Prostate Hyperplasia (BPH (n = 20) and PC (n = 22, pre- and post-operative) patients plasma. Relative telomere lengths (RLTs) in genomic DNA isolated from plasma were measured with qPCR, and telomerase activity analyzed by the ELISA method. PSA levels of PC patients were greater than of BPH patients (p = 0.0473). miR-130b-3p and miR-375 levels were significantly lower in pre-operative specimens of PC patients according to BPH (p = 0,0362, p = 0.0168, respectively). Similarly, post-operative miR-375 levels were lower in PC patients than in BPH patients (p = 0.1866). BPH patients had shorter RTLs than PC patients in both pre- (p=0.0438) and post-operative (p=0.0297) specimens. Telomerase activity was higher in PC patients than BPH(p = 0.0129). Interestingly, telomerase activity was further increased after surgery (p = 0.0003). We aim to identify the levels of miR-130b-3p and miR-375 expression and their relationship with telomerase activity in PC patients. Our data suggest that miRNAs and telomere length (TL) with telomerase activity may play a role in regulating prostate tumorgenesis and may be used as biomarkers for PC diagnosis.

Ubiquitin-specific proteases: From biological functions to potential therapeutic applications in gastric cancer

Deubiquitination, a post-translational modification regulated by deubiquitinases, is essential for cancer initiation and progression. Ubiquitin-specific proteases (USPs) are essential elements of the deubiquitinase family, and are overexpressed in gastric cancer (GC). Through the regulation of several signaling pathways, such as Wnt/β-Catenin and nuclear factor-κB signaling, and the promotion of the expression of deubiquitination- and stabilization-associated proteins, USPs promote the proliferation, metastasis, invasion, and epithelial-mesenchymal transition of GC. In addition, the expression of USPs is closely related to clinicopathological features, patient prognosis, and chemotherapy resistance. USPs therefore could be used as prognostic biomarkers. USP targeting small molecule inhibitors have demonstrated strong anticancer activity. However, they have not yet been tested in the clinic. This article provides an overview of the latest fundamental research on USPs in GC, aiming to enhance the understanding of how USPs contribute to GC progression, and identifying possible targets for GC treatment to improve patient survival.

SOX4 silencing alleviates renal injury in rats with acute renal failure by inhibiting the NF-κB signaling pathway and reducing apoptosis and oxidative stress

Acute renal failure (ARF) is a huge threat to the lives of most patients in intensive care units, and there is currently no satisfactory treatment strategy. SRY-box transcription factor 4 (SOX4) plays a key role in the development of various diseases, but its effect on ARF is unknown. Therefore, this study aimed to explore the relationship between SOX4 and ARF. Blood samples were collected from 20 ARF patients and 20 healthy volunteers. We also established an ARF rat model by excising the right kidney and ligating the left renal artery, and SOX4 knockdown in ARF rats was achieved down by means of lentiviral infection. Subsequently, we used quantitative polymerase chain reaction and western bolt assays to detect the expression levels of SOX4 and nuclear factor-κB (NF-κB) signaling pathway-related proteins in human blood or rat renal tissue and hematoxylin and eosin and terminal deoxynucleotidyl transferase (TdT) 2'-deoxyuridine 5'-triphosphate (dUTP) nick-end labeling staining to observe the pathological changes and apoptosis of renal tissue. Enzyme-linked immunosorbent assay and biochemical kits were used to measure the levels of renal function-related indicators (blood urea nitrogen, creatinine, and neutrophil gelatinase-associated lipocalin) and inflammatory factors (interleukin [IL]-1β, IL-6, and tumor necrosis factor-alpha), as well as changes in oxidative stress-related indicators (malondialdehyde [MDA], superoxide dismutase [SOD], and reactive oxygen species [ROS]) in rat serum. SOX4 expression levels in blood samples from ARF patients and renal tissue from ARF rats were significantly higher compared with those in healthy volunteers and control rats, respectively. ARF model rats displayed the typical ARF phenotype, while SOX4 silencing significantly improved pathological injury and apoptosis of renal tissue in ARF rats. Moreover, SOX4 silencing significantly inhibited increased levels of renal function-related indicators and inflammatory factors and reduced the level of excessive oxidative stress (MDA and ROS were upregulated, and SOD was downregulated) in ARF rats. SOX4 also reduced the activity of the NF-κB signaling pathway in ARF samples. Thus, SOX4 knockdown may reduce oxidative stress, the inflammatory response, and apoptosis by reducing the activity of the NF-κB signaling pathway, thereby improving renal injury in ARF rats.

CircDENND2D Inhibits PD-L1-Mediated Non-Small Cell Lung Cancer Metastasis and Immune Escape by Regulating miR-130b-3p/STK11 Axis

Local recurrence and distant metastasis of non-small cell lung cancer (NSCLC) caused by immune escape is one of the root causes of treatment difficulties. We aim to investigate the mechanism of immune escape in NSCLC. NSCLC tissues were collected. Cell proliferation was detected by CCK-8 assay. Cell migration and invasion ability was measured by Transwell assay. The expressions of E-cadherin, N-cadherin and PD-L1 were detected by Western blot. NSCLC cells were co-cultured with CD8+ T cells to simulate tumor microenvironment in vitro. The proportion of CD8+ T cells and apoptosis were detected by flow cytometry. Dual-luciferase reporter gene assay confirmed the targeting relationship of circDENND2D and STK11. The expressions of circDENND2D and STK1 were down-regulated, while miR-130b-3p expression was up-regulated in NSCLC tissues. Overexpression of circDENND2D or STK11 inhibited NSCLC cells proliferation, migration and invasion, and attenuated the immune escape of NSCLC cells. CircDENND2D targeted miR-130b-3p to competitively promote STK11 expression. STK11 knockdown or miR-130b-3p overexpression attenuated the function of circDENND2D overexpression on NSCLC cells. CircDENND2D inhibited metastasis and immune escape of NSCLC by regulating miR-130b-3p/STK11 axis.

Research Progress for Targeting Deubiquitinases in Gastric Cancers

Gastric cancers (GCs) are malignant tumors with a high incidence that threaten global public health. Despite advances in GC diagnosis and treatment, the prognosis remains poor. Therefore, the mechanisms underlying GC progression need to be identified to develop prognostic biomarkers and therapeutic targets. Ubiquitination, a post-translational modification that regulates the stability, activity, localization, and interactions of target proteins, can be reversed by deubiquitinases (DUBs), which can remove ubiquitin monomers or polymers from modified proteins. The dysfunction of DUBs has been closely linked to tumorigenesis in various cancer types, and targeting certain DUBs may provide a potential option for cancer therapy. Multiple DUBs have been demonstrated to function as oncogenes or tumor suppressors in GC. In this review, we summarize the DUBs involved in GC and their associated upstream regulation and downstream mechanisms and present the benefits of targeting DUBs for GC treatment, which could provide new insights for GC diagnosis and therapy.

miR-130-CYLD Axis Is Involved in the Necroptosis and Inflammation Induced by Selenium Deficiency in Pig Cerebellum

Selenium (Se) is an essential trace element in creatures which deficiency can cause necroptosis and inflammation of multiple tissues. MicroRNAs (miRNAs) have been identified to participate multiple biological processes by regulating the expression of target genes. In the present study, the Se-deficient pig cerebellar model was established and conducted by light microscopy, qRT-PCR, and Western blot. Morphological observation exhibited necrosis-like lesions and inflammatory infiltration in the cerebellum of the Se-deficient group. Quantitative analysis result showed that Se deficiency significantly suppressed miR-130 expression, which in turn disinhibited the expression of CYLD. Meanwhile, in comparison to the control group, the expression levels of TNF-α pathway genes (TNF-α, TNFR1, and NF-κB p65) and necroptosis-related genes (RIPK1, RIPK3, and MLKL) in Se deficiency group were obviously increased (P < 0.05). Moreover, Se deficiency induced the occurrence of inflammation by upregulating the expression of inflammatory cytokines (IL-1β, IL-2, IL-8, IL-18, IFN-γ, COX-2, PTGEs, and NLRP3). In conclusion, we proved Se deficiency could induce the deregulation of miR-130-CYLD axis to cause RIPK3-dependent necroptosis and inflammation in pig cerebellum.

MicroRNA-130b functions as an oncogene and is a predictive marker of poor prognosis in lung adenocarcinoma

Lung cancer is an aggressive disease and the leading cause of cancer-related deaths worldwide. In the past several decades, the incidence of adenocarcinoma has significantly increased, and accounts for ~40% of all lung cancer cases. In the present study, we investigated the clinicopathologic significance of microRNA-130b (miR-130b) in lung adenocarcinoma and analyzed its cancer-specific functions. RNA was extracted from formalin-fixed paraffin-embedded specimens of 146 lung adenocarcinoma cases, and miR-130b expression was analyzed using quantitative real-time polymerase chain reaction. NCI-H1650 cells were transfected with miR-130b mimic and inhibitor to determine its effects on tumor cell proliferation, migration, and invasion. The expression of miR-130b in lung adenocarcinoma tissues was classified into two groups according to the median value. High expression of miR-130b was associated with higher histological grade, advanced pathologic T stage, lymph node metastasis, and lymphovascular invasion. Moreover, survival analysis showed that high miR-130b expression was significantly associated with unfavorable prognosis. In addition, miR-130b upregulation promoted cell migration and invasion, while its downregulation resulted in decreased cell proliferation, migration, and wound healing in in vitro experiments. In conclusion, these findings suggest that miR-130b promotes tumor progression and serves as a biomarker of poor prognosis for patients with lung adenocarcinoma. Hence, targeting miR-130b may serve as a potential therapeutic strategy for lung cancer.

MiR130b from Schlafen4+ MDSCs stimulates epithelial proliferation and correlates with preneoplastic changes prior to gastric cancer

The myeloid differentiation factor Schlafen4 (Slfn4) marks a subset of myeloid-derived suppressor cells (MDSCs) in the stomach during Helicobacter-induced spasmolytic polypeptide-expressing metaplasia (SPEM).

OBJECTIVE

To identify the gene products expressed by Slfn4⁺-MDSCs and to determine how they promote SPEM.

DESIGN

We performed transcriptome analyses for both coding genes (mRNA by RNA-Seq) and non-coding genes (microRNAs using NanoString nCounter) using flow-sorted SLFN4⁺ and SLFN4^- cells from Helicobacter-infected mice exhibiting metaplasia at 6 months postinfection. Thioglycollate-elicited myeloid cells from the peritoneum were cultured and treated with IFNα to induce the T cell suppressor phenotype, expression of MIR130b and SLFN4. MIR130b expression in human gastric tissue including gastric cancer and patient sera was determined by qPCR and in situ hybridisation. Knockdown of MiR130b in vivo in Helicobacter-infected mice was performed using Invivofectamine. Organoids from primary gastric cancers were used to generate xenografts. ChIP assay and Western blots were performed to demonstrate NFκb p65 activation by MIR130b.

RESULTS

MicroRNA analysis identified an increase in MiR130b in gastric SLFN4⁺ cells. Moreover, MIR130b colocalised with SLFN12L, a human homologue of SLFN4, in gastric cancers. MiR130b was required for the T-cell suppressor phenotype exhibited by the SLFN4⁺ cells and promoted Helicobacter-induced metaplasia. Treating gastric organoids with the MIR130b mimic induced epithelial cell proliferation and promoted xenograft tumour growth.

CONCLUSION

Taken together, MiR130b plays an essential role in MDSC function and supports metaplastic transformation.

The role of deubiquitinating enzymes in gastric cancer

The epigenetic regulation of gene expression (via DNA methylation, histone modification and microRNA interference) contributes to a variety of diseases, particularly cancer. Protein deubiquitination serves a key role in the mechanism underlying histone modification, and consequently influences tumor development and progression. Improved characterization of the role of ubiquitinating enzymes has led to the identification of numerous deubiquitinating enzymes (DUBs) with various functions. Gastric cancer (GC) is a highly prevalent cancer type that exhibits a high mortality rate. Latest analysis about cancer patient revealed that GC is sixth deadliest cancer type, which frequently occur in male (7.2%) than female (4.1%). Complex associations between DUBs and GC progression have been revealed in multiple studies; however, the molecular mechanism underpinning the metastasis and recurrence of GC is yet to be elucidated. Generally, DUBs were upregulated in gastric cancer. The relation of DUBs and tumor size, classification and staging was observed in GC. Besides, 5-yar survival rate of patients with GC is effeccted by expression level of DUBs. Among the highly expressed DUBs, specifically six DUBs namely UCHs, USPs, OTUs, MJDs, JAMMs and MCPIPs effect on this survival rate. Consequently, the association between GC and DUBs has received increasing attention in recent years. Therefore, in the present review, literature investigating the association between DUBs and GC pathophysiology was analyzed and critically appraised.

Aberrant expression and mechanism of miR-130b-3p/phosphatase and tensin homolog in nephroblastoma in children

Nephroblastoma is the most common renal tumor in children. Abnormal expression of microRNAs (miRs) has been reported to be involved in the progression of various types of cancers. However, the role and underlying mechanism of miR-130b-3p in nephroblastoma remains unknown. Therefore, the present study aimed to explore the role and possible mechanism of miR-130b-3p in nephroblastoma in children. The present study identified that miR-130b-3p was highly expressed in nephroblastoma tissues obtained from children with nephroblastoma. To better understand the functions and the molecular mechanisms of miR-130b-3p in nephroblastoma, TargetScan was used to identify the potential targets of miR-130b-3p. Phosphatase and tensin homolog (PTEN), was identified as a target gene of miR-130b-3p, and it was observed to be downregulated in nephroblastoma. Further analysis indicated that miR-130b-3p inhibitor could significantly reduce cell proliferation, induce apoptosis and suppress the Akt/nuclear factor-κB/survivin signaling pathway in nephroblastoma cells. Notably, all these effects of miR-130b-3p on nephroblastoma cells were reversed by PTEN-small interfering RNA. In summary, the present study suggested that the miR-130b-3p/PTEN axis could serve a critical role in the progression and development of nephroblastoma. It also suggests that miR-130b-3p might be a valuable clinical biomarker and therapeutic target for nephroblastoma in children.

Signature microRNAs and long noncoding RNAs in laryngeal cancer recurrence identified using a competing endogenous RNA network

The aim of the present study was to identify novel microRNA (miRNA) or long noncoding RNA (lncRNA) signatures of laryngeal cancer recurrence and to investigate the regulatory mechanisms associated with this malignancy. Datasets of recurrent and nonrecurrent laryngeal cancer samples were downloaded from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus database (GSE27020 and GSE25727) to examine differentially expressed miRNAs (DE-miRs), lncRNAs (DE-lncRs) and mRNAs (DEGs). miRNA-mRNA and lncRNA-miRNA networks were constructed by investigating the associations among these RNAs in various databases. Subsequently, the interactions identified were combined into a competing endogenous RNA (ceRNA) regulatory network. Feature genes in the miRNA-mRNA network were identified via topological analysis and a recursive feature elimination algorithm. A support vector machine (SVM) classifier was established using the betweenness centrality values in the miRNA-mRNA network, consisting of 32 optimal feature-coding genes. The classification effect was tested using two validation datasets. Furthermore, coding genes in the ceRNA network were examined via pathway enrichment analyses. In total, 21 DE-lncRs, 507 DEGs and 55 DE-miRs were selected. The SVM classifier exhibited an accuracy of 94.05% (79/84) for sample classification prediction in the TCGA dataset, and 92.66 and 91.07% in the two validation datasets. The ceRNA regulatory network comprised 203 nodes, corresponding to mRNAs, miRNAs and lncRNAs, and 346 lines, corresponding to the interactions among RNAs. In particular, the interactions with the highest scores were HLA complex group 4 (HCG4)-miR-33b, HOX transcript antisense RNA (HOTAIR)-miR-1-MAGE family member A2 (MAGEA2), EMX2 opposite strand/antisense RNA (EMX2OS)-miR-124-calcitonin related polypeptide α (CALCA) and EMX2OS-miR-124-γ-aminobutyric acid type A receptor γ2 subunit (GABRG2). Gene enrichment analysis of the genes in the ceRNA network identified that 11 pathway terms and 16 molecular function terms were significantly enriched. The SVM classifier based on 32 feature coding genes exhibited high accuracy in the classification of laryngeal cancer samples. miR-1, miR-33b, miR-124, HOTAIR, HCG4 and EMX2OS may be novel biomarkers of recurrent laryngeal cancer, and HCG4-miR-33b, HOTAIR-miR-1-MAGEA2 and EMX2OS-miR-124-CALCA/GABRG2 may be associated with the molecular mechanisms regulating recurrent laryngeal cancer.

Gga-miR-130b-3p inhibits MSB1 cell proliferation, migration, invasion, and its downregulation in MD tumor is attributed to hypermethylation

Marek's disease is an oncogenic and lymphoproliferative disease of chickens caused by Marek's disease virus. Hypermethylation or hypomethylation of CpG islands in gene promoter region are involved in the initiation and progression of carcinogenesis. In this study, we analyzed differential methylation levels of upstream region of gga-miR-130b-3p gene between Marek's disease virus-infected tumorous and non-infected spleens. Around the upstream 1 kb of gga-miR-130b-3p gene, two amplicons were designed that covered 616 bp. There were forty-eight CpG sites in this region. CpG sites in this region presented higher methylation level in tumorous spleens compared with that in non-infected ones. There were eight CpG sites significantly hypermethylated in tumorous spleens. The expression level of three DNA methyltransferases including DNMT1, DNMT3a and DNMT3b increased and the expression level of Tet ten-eleven translocation protein 2 remarkably decreased in tumorous spleens. Hypermethylation in the upstream region of gga-miR-130b-3p gene might be a direct reason for its downregulation in MD tumorous tissues. Moreover, cell proliferation of Marek's disease lymphoblastoid cell line MDCC-MSB1 was remarkably inhibited at 24, 36, 48, 60 and 72 h post-gga-miR-130b-3p-agomir transfection. The transwell migration assay indicated cell number of migration was significantly lower in miRNA agomir transfection group. Matrix metalloproteinases MMP2 and MMP9 are involved in tumor invasion, and their protein levels were significantly downregulated at 72 h post-miRNA-agomir transfection. Collectively, these results indicated that hypermethylation in upstream region of gga-miR-130b-3p gene contributed to its downregulation in tumorous tissues. Gga-miR-130b-3p plays an inhibitory role in lymphomatous cell transformation.

MicroRNA-130b targets PTEN to induce resistance to cisplatin in lung cancer cells by activating Wnt/β-catenin pathway

More and more studies indicate the relevance of miRNAs in inducing certain drug resistance. Our study aimed to investigate whether microRNA‐130b‐3p (miR‐130b) mediates the chemoresistance as well as proliferation of lung cancer (LC) cells. MTS assay and apoptosis analysis were conducted to determine cell proliferation and apoptosis, respectively. Binding sites were identified using a luciferase reporter system, whereas mRNA and protein expression of target genes was determined by RT‐PCR and immunoblot, respectively. Mouse xenograft model was used to evaluate the role of miR‐130b in cisplatin resistance in vivo. The rising level of miR‐130b in cisplatin resistance LC cell lines (A549/CR and H446/CR) versus its parental cell lines, indicated its crucial relevance for LC biology. We identified PTEN as miR‐130b's major target and inversely correlated with miR‐130b expression in LC. Moreover, excessive miR‐130b expression promoted drug resistance and proliferation, decreased apoptosis of A549 cells. Suppression of miR‐130b enhanced drug cytotoxicity and reduced proliferation of A549/CR cells both internally and externally. Particularly, miR‐130b mediated Wnt/β‐catenin signalling pathway activities, chemoresistance and proliferation in LC cell, which was partially blocked following knockdown of PTEN. These findings suggest that miR‐130b targets PTEN to mediate chemoresistance, proliferation, and apoptosis via Wnt/β‐catenin pathway. The rising level of miR‐130b in cisplatin resistance LC cell lines (A549/CR and H446/CR) versus its parental cell lines, indicated its crucial relevance for LC biology. Moreover, excessive miR‐130b expression promoted drug resistance and proliferation, decreased apoptosis of A549 cells. These findings suggest that miR‐130b targets PTEN to mediate chemoresistance, proliferation, and apoptosis via Wnt/β‐catenin pathway.

miR-130b regulates the proliferation, invasion and apoptosis of glioma cells via targeting of CYLD

MicroRNAs are short non-coding RNAs that play important roles in gliomas. However, the role of miR-130b in glioma remains unclear. In the present study, miR-130b expression was upregulated in glioma tissues and cell lines. Kaplan-Meier analysis indicated that the upregulation of miR-130b expression correlated with poor prognoses in glioma patients. Multivariate analysis demonstrated that this upregulation and a high-grade classification were independent factors that both predicted poor outcomes for glioma patients. Dual-luciferase assays identified that the cylindromatosis (CYLD) gene is a direct target of miR-130b. Functional studies demonstrated that a miR-130b mimic significantly promoted the growth and invasion of glioma cells, while also inhibiting apoptosis via selective targeting of CYLD, which was enhanced by CYLD-targeted siRNA. In contrast, a miR‑130b inhibitor suppressed these biological behaviors, and this inhibition was reversed by CYLD-targeted siRNA. These data revealed that miR-130b could act as a novel potential diagnostic biomarker for glioma, while also demonstrating the importance of miR‑130b in the cell proliferation and progression of glioma, indicating that it may serve as a useful therapeutic target for glioma.

MicroRNA-130b transcriptionally regulated by histone H3 deacetylation renders Akt ubiquitination and apoptosis resistance to 6-OHDA

Apoptosis of DA neurons is a contributing cause of disability and death for Parkinson's disease (PD). Akt may become a potential therapeutic target for PD since Akt has been deactivated during DA neuron apoptosis. We previously demonstrated that Akt confers apoptosis resistance against 6-OHDA in DA neuron-like PC12 cells, yet the underlying mechanisms accounted for this are not fully understood. Here we report that microRNA-130b (miR-130b)-dependent and cylindromatosis (CYLD) repression-mediated Akt ubiquitination renders apoptosis resistance of PC12 cells to 6-OHDA, which elicits histone H3 deacetylation-induced transcriptional downregulation of miR-130b vice versa. CYLD deficiency ubiquitinates Akt at Lys63, thereby phosphorylating Akt and antagonizing 6-OHDA-initiated apoptosis. MiR-130b targetedly represses CYLD and increases apoptosis resistance to 6-OHDA. CYLD repression by miR-130b restores Akt ubiquitination and activation, GSK3β and FoxO3a phosphorylation, FoxO3a removal from Bim promoter as well as Bim downregulation during 6-OHDA administration. CYLD deficiency-mediated Akt activation is instrumental for the apoptosis-resistant phenotypes of miR-130b. In addition, 6-OHDA transcriptionally downregulates miR-130b through recruitment of HDAC3 at the promoter. Furthermore, EPO potentiates the ability of miR-130b to activate Akt and augment apoptosis resistance. Our findings identify the apoptosis-resistant function of miR-130b and suggest that histone H3 deacetylation plays a pivotal role in regulating miR-130b transcription in response to 6-OHDA.

MicroRNA-130b promotes cell migration and invasion by inhibiting peroxisome proliferator-activated receptor-γ in human glioma

Glioma is the most common and aggressive type of primary brain tumor. MicroRNA (miR)-130b functions as a tumor-associated miR. The dysregulation of miR-130b is involved in numerous biological characteristics and properties of certain types of cancer. The present study revealed the function and possible molecular mechanism of miR-130b in glioma cells, reporting that the level of miR-130b was markedly higher, increasing progressively as the histologic grade of the glioma increased, compared with the level in normal tissues. Additionally, the present study demonstrated that patients with high miR-130b expression exhibited a poor 3-year survival rate and miR-130b was an independent factor for predicting the prognosis of patients with glioma. The downregulation of miR-130b reduced invasion and migration in U373 and U87 cells. Furthermore, the downregulation of miR-130b increased peroxisome proliferator-activated receptor-γ (PPARγ) expression and inhibited epithelial-mesenchymal transition (EMT) in glioma cells. The present study identified PPARγ as a direct target of miR-130b in glioma in vitro. Furthermore, PPARγ knockdown was revealed to reduce the effect on EMT caused by the downregulation of miR-130b in U87 cells. The present study demonstrated that miR-130b promotes glioma proliferation, migration and invasion by suppressing PPARγ and subsequently inducing EMT.

MicroRNA-130b targets PTEN to mediate drug resistance and proliferation of breast cancer cells via the PI3K/Akt signaling pathway

Multidrug resistance (MDR) correlates with treatment failure and poor prognosis among breast cancer patients. This study was aimed to investigate the possible mechanism by which microRNA-130b-3p (miR-130b) mediates the chemoresistance and proliferation of breast cancer. MiR-130b was found to be up-regulated in tumor tissues versus adjacent tissues of breast cancer, as well as in adriamycin (ADR) resistant breast cancer cell line (MCF-7/ADR) versus its parental line (MCF-7) and the non-malignant breast epithelial cell line (MCF-10A), demonstrating its crucial relevance for breast cancer biology. We identified that PTEN was a direct target of miR-130b and inversely correlated with miR-130b expression in breast cancer. Moreover, over-expression of miR-130b promoted drug resistance, proliferation and decreased apoptosis of MCF-7 cells, while suppression of miR-130b enhanced drug cytotoxicity and apoptosis, as well as reduced proliferation of MCF-7/ADR cells in vitro and in vivo. Particularly, miR-130b mediated the activity of phosphoinositide-3 kinase (PI3K)/Akt signaling pathway as well as the chemoresistance and proliferation of breast cancer cell lines, which was partially blocked following knockdown of PTEN. Altogether, miR-130b targets PTEN to induce MDR, proliferation, and apoptosis via PI3K/Akt signaling pathway. This provides a novel promising candidate for breast cancer therapy.

miR-130b-3p inhibits cell invasion and migration by targeting the Notch ligand Delta-like 1 in breast carcinoma

Breast carcinoma is the most common malignancy in women, and the incidence rate has increased dramatically in recent years. Metastasis is responsible for most advanced breast cancer mortality, but the underlying mechanisms remain poorly understood despite extensive research. Recently, short non-coding RNA molecules, including miRNAs, which mediate changes in signalling pathways, have emerged as metastatic regulators of the breast carcinoma. Previous reports have suggested that miR-130b-3p has both oncogenic and tumour suppressor functions in a cancer type-dependent manner. However, the roles and underlying molecular mechanisms of miR-130b-3p in the development of metastasis in breast carcinoma remain unclear. Here, we reported for the first time that miR-130b-3p was differentially expressed in early-stage non-invasive MCF-7 human breast carcinoma cells and aggressive late-stage MDA-MB-231 cells. In gain-of-function and loss-of-function studies, we demonstrated that miR-130b-3p could inhibit breast carcinoma cell invasion and migration by directly targeting the Notch ligand Delta-like 1 (DLL1). Our data also indicated that MMP-9, MMP-13, and VEGF were regulated by miR-130b-3p and may be involved in the inhibition of cell invasion and migration in breast carcinoma. Collectively, our findings reveal a new regulatory mechanism of miR-130b-3p and suggest that miR-130b-3p may be a potential target against human breast cancer metastasis.