MiR-577 suppresses epithelial-mesenchymal transition and metastasis of breast cancer by targeting Rab25

Knocking-down long non-coding RNA LINC01094 prohibits chondrocyte apoptosis via regulating microRNA-577/metal-regulatory transcription factor 1 axis

PURPOSE

The abnormal function and survival of chondrocytes result in articular cartilage failure, which may accelerate the onset and development of osteoarthritis (OA). This study is aimed to investigate the role of LINC01094 in chondrocyte apoptosis.

METHODS

The viability and apoptosis of lipopolysaccharide (LPS)-induced chondrocytes were evaluated through CCK-8 assay and flow cytometry analysis, respectively. The expression levels of LINC01094, miR-577 and MTF1 were detected by qRT-PCR. Dual luciferase reporter tests were implemented for the verification of targeted relationships among them. Western blotting was employed to measure the levels of pro-apoptotic proteins (Caspase3 and Caspase9).

RESULTS

The viability of LPS-induced chondrocytes was overtly promoted by loss of LINC01094 or miR-577 upregulation, but could be repressed via MTF1 overexpression. The opposite results were observed in apoptosis rate and the levels of Caspase3 and Caspase9. LINC01094 directly bound to miR-577, while MTF1 was verified to be modulated by miR-577. Both LINC01094 and MTF1 were at high levels, whereas miR-577 was at low level in OA synovial fluid and LPS-induced chondrocytes. Furthermore, the highly expressed miR-577 abolished the influences of MTF1 overexpression on LPS-induced chondrocytes.

CONCLUSIONS

Silencing of LINC01094 represses the apoptosis of chondrocytes through upregulating miR-577 expression and downregulating MTF1 levels, providing a preliminary insight for the treatment of OA in the future.

Circ_0000376 regulates miR-577/HK2/LDHA signaling pathway to promote the growth, invasion and glycolysis of osteosarcoma

BACKGROUND

Many studies have confirmed that circular RNAs (circRNAs) mediate the malignant progression of various tumors including osteosarcoma (OS). Our study is to uncover novel molecular mechanisms by which circ_0000376 regulates OS progression.

METHODS

The expression of circ_0000376, microRNA (miR)-577, hexokinase 2 (HK2) and lactate dehydrogenase-A (LDHA) was determined by quantitative real-time PCR. OS cell proliferation, apoptosis and invasion were measured using cell counting kit 8 assay, colony formation assay, EdU assay, flow cytometry and transwell assay. Besides, cell glycolysis was assessed by testing glucose consumption, lactate production, and ATP/ADP ratios. Protein expression was examined by western blot analysis. The interaction between miR-577 and circ_0000376 or HK2/LADA was verified by dual-luciferase reporter assay. The role of circ_0000376 on OS tumor growth was explored by constructing mice xenograft models.

RESULTS

Circ_0000376 had been found to be upregulated in OS tissues and cells. Functional experiments revealed that circ_0000376 interference hindered OS cell growth, invasion and glycolysis. Circ_0000376 sponged miR-577 to reduce its expression. In rescue experiments, miR-577 inhibitor abolished the regulation of circ_0000376 knockdown on OS cell functions. MiR-577 could target HK2 and LDHA in OS cells. MiR-577 suppressed OS cell growth, invasion and glycolysis, and these effects were reversed by HK2 and LDHA overexpression. Also, HK2 and LDHA expression could be regulated by circ_0000376. In vivo experiments showed that circ_0000376 knockdown inhibited OS tumorigenesis.

CONCLUSION

Circ_0000376 contributed to OS growth, invasion and glycolysis depending on the regulation of miR-577/HK2/LDHA axis, providing a potential target for OS treatment.

miRSCAPE - inferring miRNA expression from scRNA-seq data

Our understanding of miRNA activity at cellular resolution is thwarted by the inability of standard scRNA-seq protocols to capture miRNAs. We introduce a novel tool, miRSCAPE, to infer miRNA expression in a sample from its RNA-seq profile. We establish miRSCAPE’s accuracy in 10 tumor and normal cohorts demonstrating its superiority over alternatives. miRSCAPE accurately infers cell type-specific miRNA activities (predicted versus observed fold-difference correlation ∼0.81) in two independent scRNA-seq datasets. We apply miRSCAPE to infer miRNA activities in scRNA clusters in pancreatic and lung adenocarcinomas, as well as in 56 cell types in the human cell landscape (HCL). In pancreatic and breast cancer scRNA-seq data, miRSCAPE recapitulates miRNAs associated with stemness and epithelial-mesenchymal transition (EMT) cell states, respectively. Overall, miRSCAPE recapitulates and refines miRNA biology at cellular resolution. miRSCAPE is freely available and is easily applicable to scRNA-seq data to infer miRNA activities at cellular resolution.

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Novel machine learning-based tool to infer miRNA expression at single cell level

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Predicts miRNA activity with high accuracy in various contexts

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Recaps miRNAs associated with specific cellular states and suggests novel candidates

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Provides a general framework to predict other types of molecular data at a single cell

N6-methyladenosine-mediated upregulation of LINC00520 accelerates breast cancer progression via regulating miR-577/POSTN axis and downstream ILK/AKT/mTOR signaling pathway

Various lncRNAs have been reported to be closely associated with cancer initiation and progression in breast cancer (BC), including LINC00520. However, the role and underlying mechanisms by which LINC00520 affects BC aggressiveness have not been fully delineated, and this study aimed to explore this issue. Through performing qRT-PCR analysis, we proved that LINC00520 was significantly upregulated in BC tissues and cells, compared with normal tissues and cells. Higher expression of LINC00520 was closely related to higher tumor grade, poor differentiation and shorter survival in BC patients. Next, the loss-of-function experiments evidenced that silencing LINC00520 suppressed BC cell proliferation, migration and epithelial-mesenchymal transition (EMT) in vitro, and inhibited tumorigenesis in vivo. Interestingly, we found that LINC00520 expression was positively regulated by METTL3-mediated N6-methyladenosine(m⁶A) modification in BC. Furthermore, we identified the tumor-suppressor miR-577 as the binding target of LINC00520 in BC. Mechanistically, LINC00520 elevated POSTN level via sponging miR-577, resulting in the activation of the downstream tumor-promoting ILK/Akt/mTOR pathway. Finally, the rescuing experiments evidenced that both POSTN knockdown and ILK/Akt/mTOR pathway inhibitor OSU-T315 abrogated the promoting effects of miR-577 ablation on the malignant phenotypes in BC. Collectively, this study firstly verified that LINC00520 acted as a ceRNA of miR-577 to advance BC aggressiveness in a m⁶A-dependent manner, providing novel biomarkers for BC diagnosis and therapy.

Long noncoding RNA regulatory factor X3- antisense RNA 1 promotes non-small cell lung cancer via the microRNA-577/signal transducer and activator of transcription 3 axis

Lung cancer is the most frequent malignancy, and non-small cell lung cancer (NSCLC) is its most common pathological type. Molecular targeted therapy has been testified to be effective in intervening in the occurrence and development of malignancies. This study investigates the effect of lncRNA Regulatory Factor X3- antisense RNA 1 (RFX3-AS1) in NSCLC progression. The RFX3-AS1 profile in NSCLC tissues and cells was measured by quantitative reverse transcription PCR (qRT-PCR). The RFX3-AS1 overexpression model was constructed. The cell counting kit-8 (CCK-8) experiment and cell colony formation assay were adopted to test cell viability. The cell apoptosis was determined by flow cytometry (FCM). Cell migration and invasion were monitored by the Transwell assay, and Western blot was implemented to verify the protein profiles of signal transducer and activator of transcription 3 (STAT3), E-cadherin, Vimentin and N-cadherin. In vivo, we validated the impact of RFX3-AS1 overexpression on the NSCLC xenograft mouse model. The targeting relationships between RFX3-AS1 and miR-577, miR-577 and STAT3 were confirmed by the dual-luciferase reporter assay. The results manifested that overexpressing RFX3-AS1 markedly facilitated NSCLC cell proliferation, migration, invasion and epithelial-mesenchymal transition (EMT), and suppressed cell apoptosis. In contrast, miR-577, which was a downstream target of RFX3-AS1, dramatically impeded the malignant biological behaviors of NSCLC cells. STAT3 was a direct target of miR-577, and it was negatively regulated by the latter. STAT3 activation reversed miR-577-mediated anti-tumor roles. In brief, RFX3-AS1 aggravated NSCLC progression by regulating the miR-577/STAT3 axis.

Integrative analysis of TCGA data identifies miRNAs as drug-specific survival biomarkers

Biomarkers predictive of drug-specific outcomes are important tools for personalized medicine. In this study, we present an integrative analysis to identify miRNAs that are predictive of drug-specific survival outcome in cancer. Using the clinical data from TCGA, we defined subsets of cancer patients who suffered from the same cancer and received the same drug treatment, which we call cancer-drug groups. We then used the miRNA expression data in TCGA to evaluate each miRNA’s ability to predict the survival outcome of patients in each cancer-drug group. As a result, the identified miRNAs are predictive of survival outcomes in a cancer-specific and drug-specific manner. Notably, most of the drug-specific miRNA survival markers and their target genes showed consistency in terms of correlations in their expression and their correlations with survival. Some of the identified miRNAs were supported by published literature in contexts of various cancers. We explored several additional breast cancer datasets that provided miRNA expression and survival data, and showed that our drug-specific miRNA survival markers for breast cancer were able to effectively stratify the prognosis of patients in those additional datasets. Together, this analysis revealed drug-specific miRNA markers for cancer survival, which can be promising tools toward personalized medicine.

LncRNA NORAD facilitates oral squamous cell carcinoma progression by sponging miR-577 to enhance TPM4

BACKGROUND

Long non-coding RNAs (lncRNAs) have been reported to be vital factors to affect the expression of genes and proteins. Also, it has been proved that the abnormal expression or mutation of lncRNAs stands as a signal of metastasis and proliferation of cancer. Nevertheless, the majority of lncRNAs still need to be explored in abundant cancers especially in oral squamous cell carcinoma (OSCC).

METHODS

RT-qPCR assays were applied to test the expression of RNAs. Mechanism assays were performed to verify the combination among NORAD, TPM4 and miR-577. Also, functional assays were conducted to verify the function of RNAs on OSCC cells.

RESULTS

LncRNA NORAD was highly expressed in OSCC tissues and cells. NORAD silencing repressed the biological behaviors of OSCC cells. MiR-577 was found in OSCC with low expression, and RIP assays illustrated that NORAD, miR-577 and TPM4 coexisted in RNA-induced silencing complexes. Rescue assays proved that the overexpression of TPM4 could recover the effect of NORAD silencing on OSCC progression.

CONCLUSIONS

It was revealed that NORAD functioned as a tumor promoter to sponge miR-577 thus elevating TPM4 in OSCC, which indicated that NORAD was worthy to be studied as a target for the treatment of OSCC.

Targeting miR-185-3p Inhibits Head and Neck Squamous Cell Carcinoma by Modulating RAB25

Cancer cell-derived exosomes regulate tumor growth and progression. However, the effects of exosomes and its contents on head and neck squamous cell carcinoma (HNSCC) and its underlying mechanisms remain unclear. Here, we found HNSCC displayed a dysregulation of exosomes biogenesis. miR-185-3p was one of the most upregulated exosome-derived miRNAs in HNSCC. Functional assay showed that RAB25 is a direct downstream target of miR-185-3p. miR-185-3p/RAB25 signaling controlled tumor progression and correlated with disease prognosis. Targeting miR-185-3p/RAB25 significantly inhibited tumor growth and promoted drug response to chemotherapy. To conclude, the findings demonstrate exosomal miR-185-3p promotes tumor growth by mediating RAB25 that could be effectively targeted for HNSCC treatment.

LncRNA POT1-AS1 accelerates the progression of gastric cancer by serving as a competing endogenous RNA of microRNA-497-5p to increase PDK3 expression

BACKGROUND

Gastric cancer (GC) is the most common malignant tumor of the digestive system. Although progress has been reported in terms of treatment, it is still the second leading cause of cancer-related death. Long non-coding RNAs have been shown to play a key role in human cancers in recent investigations. However, the role of POT1-AS1 in GC is still unclear.

METHODS

The relative POT1-AS1 level in GC tissues and paracancerous tissues was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The biological function of POT1-AS1 was studied by CCK8 and Transwell assays in vitro experiments. Moreover, the downstream target genes of POT1-AS1 were predicted by bioinformatics.

RESULTS

In this study, high POT1-AS1 expression in GC cells was confirmed, and its elevated expression was linked to patients' negative clinicopathological characteristics, as well as shorter disease-free survival (DFS) and overall survival (OS). POT1-AS1 was shown to serve as a competing endogenous RNA (ceRNA) by sponging miR-497-5p to increase PDK3 expression. The impact of POT1-AS1 silencing on GC malignant phenotypes could be reversed by suppressing miR-497-5p or restoring PDK3, according to rescue experiments.

CONCLUSIONS

In brief, POT1-AS1 acted as an oncogenic lncRNA in GC, facilitating GC development by affecting the miR-497-5p/PDK3 axis, implying that the POT1-AS1/miR-497-5p/PDK3 axis is a useful target in anticancer therapy.

FGD5‑AS1 is an oncogenic lncRNA in pancreatic cancer and regulates the Wnt/β‑catenin signaling pathway via miR‑577

The objective of the present study was to clarify the expression characteristics of long non-coding RNA (lncRNA) FGD5 antisense RNA 1 (FGD5-AS1) in pancreatic cancer, as well as its biological function and underlying mechanism. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was utilized for the detection of FGD5-AS1 and microRNA (miR)-577 expression levels in pancreatic cancer tissues. Transfection was performed to upregulate or downregulate FGD5-AS1 in pancreatic cancer cell lines. MTT and Transwell assays were then utilized to detect the proliferation, migration and invasion of cancer cells, respectively. Subsequently, dual-luciferase reporter gene assay, RNA immunoprecipitation assay, RNA pull-down assay, RT-qPCR, western blotting, and Pearson's correlation analysis were employed to confirm the regulatory relationships among FGD5-AS1, miR-577, low-density lipoprotein receptor-related protein 6 (LRP6) and β-catenin. Western blotting was employed to determine the expression levels of Axin2, cyclin D1 and c-Myc. The expression level of FGD5-AS1 was upregulated in pancreatic cancer tissues and cell lines. FGD5-AS1 knockdown inhibited pancreatic cancer cell proliferation, migration and invasion. By contrast, miR-577 was significantly inhibited in pancreatic cancer cells and tissues; its downregulation promoted pancreatic cancer cell proliferation, migration and invasion, and reversed the effects of FGD5-AS1 knockdown on pancreatic cancer cells. In addition, it was revealed that miR-577 was a target of FGD5-AS1, and FGD5-AS1 could modulate the expression levels of LRP6, β-catenin, Axin2, cyclin D1 and c-Myc via suppressing miR-577. In conclusion, in pancreatic cancer, highly expressed FGD5-AS1 activated the Wnt/β-catenin signaling and promoted cancer cell proliferation, migration and invasion via suppression of miR-577.

M6A-mediated up-regulation of LncRNA LIFR-AS1 enhances the progression of pancreatic cancer via miRNA-150-5p/ VEGFA/Akt signaling

N⁶-methyladenosine (m⁶A) modification, the most abundant internal methylation of eukaryotic RNA transcripts, is critically implicated in RNA processing. There is extensive evidence indicating that long non-coding RNAs (lncRNAs) serve as key regulators of oncogenesis and tumor progression in humans. Through prior study has assessed that LIFR-AS1 plays a key role in various kinds of malignant tumors. However, the exact role of m⁶A induced LIFR-AS1 in pancreatic cancer (PC) and its potential molecular mechanisms remain largely unknown. In this study, we determined that PC cell lines and tumors exhibit increased LIFR-AS1 expression that correlates with larger tumor size, lymph node metastasis, and more advanced TNM stage. Functionally, loss-of-function studies indicated that LIFR-AS1 knockdown decreased the proliferation, migration, and invasion of PC cells in vitro. Mechanistically, we found that METTL3 induced m⁶A hyper-methylation on the 3' UTR of LIFR-AS1 to enhance its mRNA stability and LIFR-AS1 could directly interact with miR-150-5p, thereby indirectly up-regulating VEGFA expressions within cells. Through rescue experiments, we were able to confirm that the unfavorable impact of LIFR-AS1 knockdown on VEGFA /PI3K/Akt Signaling could be reversed via the inhibition of miR-150-5p expression. Together, these findings indicate that a noval m6A-LIFR-AS1 axis promotes PC progression at least in part via regulation of the miR-150-5p/VEGFA axis, indicating that this regulatory axis may be a viable clinical target for the treatment of PC.

Rab6c is a new target of miR‑218 that can promote the progression of bladder cancer

Bladder cancer has high morbidity and mortality rates among the male genitourinary system tumor types. MicroRNA‑218 (miR‑218) is associated with the development of a variety of cancer types, including bladder cancer. Rab6c is a member of the Rab family and is involved in drug resistance in MCF7 cells. The aim of the present study was to clarify the relationship between Rab6c and miR‑218 in bladder cancer cell lines. In this study, the expression levels of miR‑218 and Rab6c were evaluated via reverse transcription‑quantitative PCR and western blotting, respectively. The association between Rab6c and miR‑218 was recognized via TargetScan analysis and dual luciferase reporter gene detection. Cell proliferation was analyzed using Cell Counting Kit‑8 and colony formation assays, and the invasive ability was measured via Transwell assays. Rab6c was highly expressed in bladder cancer, while miR‑218 had abnormally low expression in bladder cancer. In addition, there was a mutual regulation between Rab6c and miR‑218 in bladder cancer. It was found that overexpression of Rab6c significantly enhanced the proliferation, colony formation and invasion of T24 and EJ cells. Furthermore, miR‑218 overexpression blocked the promoting effects of Rab6c on the malignant behavior of bladder cancer cells. Thus, Rab6c promotes the proliferation and invasion of bladder cancer cells, while miR‑218 has the opposite effect, which may provide a novel insight for the treatment of bladder cancer.

circMYC promotes cell proliferation, metastasis, and glycolysis in cervical cancer by up-regulating MET and sponging miR-577

OBJECTIVE

To analyze the role of circMYC in cervical cancer.

METHODS

Protein and RNA expression was detected by RT-qPCR and western blotting. Transwell, CCK8, and colony formation assays were used for measuring metastasis, cell viability, and proliferation, respectively. Lactate production, glucose uptake, and ATP generation were examined to evaluate cell glycolysis. Interactions between circMYC, miR-577, and MET were determined by RNA pull-down and immunoprecipitation, and dual-luciferase reporter assays. Xenografts were established in mice to evaluate the functions of circMYC in vivo.

RESULTS

circMYC was overexpressed in tumor tissue, which was related to poor prognosis. CircMYC knockdown reduced proliferation, colony formation, metastasis, and glycolysis in cervical cancer cells as well as inhibiting tumor growth in vivo. Mechanistically, circMYC targeted miR-577, and the effects of circMYC knockdown could be reversed by miR-577 inhibition. Moreover, miR-577 downregulated the expression of MET. Therefore, the oncogenic role of circMYC in cervical cancer was achieved by sponging miR-577 and maintaining MET expression.

CONCLUSION

circMYC promotes cervical cancer progression through regulation of the miR-577/MET axis. circMYC may thus be a potential target for diagnosing and treating cervical cancer.

Construction and Analysis of the Dysregulated ceRNA Network and Identification of Risk Long Noncoding RNAs in Breast Cancer

Breast cancer (BRCA) is the second leading cause of cancer-related mortality in women worldwide. However, the molecular mechanism involved in the development of BRCA is not fully understood. In this study, based on the miRNA-mediated long non-coding RNA (lncRNA)-protein coding gene (PCG) relationship and lncRNA-PCG co-expression information, we constructed and analyzed a specific dysregulated lncRNA-PCG co-expression network in BRCA. Then, we performed the random walk with restart (RWR) method to prioritize BRCA-related lncRNAs through comparing their RWR score and significance. As a result, we identified 30 risk lncRNAs for BRCA, which can distinguish normal and tumor samples. Moreover, through gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis, we found that these risk lncRNAs mainly synergistically exerted functions related to cell cycle and DNA separation and replication. At last, we developed a four-lncRNA prognostic signature (including AP000851.1, LINC01977, MAFG-DT, SIAH2-AS1) and assessed the survival accuracy of the signature by performing time-dependent receiver operating characteristic (ROC) analysis. The areas under the ROC curve for 1, 3, 5, and 10 years of survival prediction were 0.68, 0.61, 0.62, and 0.63, respectively. The multivariable Cox regression results verified that the four-lncRNA signature could be used as an independent prognostic biomarker in BRCA. In summary, these results have important reference value for the study of diagnosis, treatment, and prognosis evaluation of BRCA.

CXCL5/NF-κB Pathway as a Therapeutic Target in Hepatocellular Carcinoma Treatment

Background

Hepatocellular carcinoma (HCC) is a common malignant cancer worldwide. CXCL5 has a role in inhibiting cell viability and metastasis in many tumors. In the present study, we investigated the role of CXCL5 in HCC and explored the underlying mechanism. Material and Methods. RT-qPCR and western blot were performed to evaluate the mRNA and protein levels of CXCL5. CCK-8 and transwell assay were applied to measure the proliferative and invasive abilities. Meanwhile, the Kaplan–Meier method was used to assess the survival of HCC patients.

Results

CXCL5 was upregulated in HCC tissues, which predicted a shorter overall survival in HCC. CXCL5 was a target gene of miR-577, and its expression was mediated by miR-577 in HCC. Knockdown of CXCL5 suppressed HuH-7 cell proliferation, invasion, and EMT and inhibited the NF-κB signaling pathway in cells. Moreover, knockdown of CXCL5 inhibited the xenograft growth of HuH-7 cells.

Conclusion

Overexpression of CXCL5 predicts poor prognosis in HCC patients. Knockdown of CXCL5 inhibits cell proliferation and invasion through the NF-κB signaling pathway in HCC. The newly identified role of the CXCL5/miR-577/NF-κB axis provides novel insights into the targeted therapy of HCC.

pDriver : A novel method for unravelling personalised coding and miRNA cancer drivers

MOTIVATION

Unravelling cancer driver genes is important in cancer research. Although computational methods have been developed to identify cancer drivers, most of them detect cancer drivers at population level. However, two patients who have the same cancer type and receive the same treatment may have different outcomes because each patient has a different genome and their disease might be driven by different driver genes. Therefore new methods are being developed for discovering cancer drivers at individual level, but existing personalised methods only focus on coding drivers while microRNAs (miRNAs) have been shown to drive cancer progression as well. Thus, novel methods are required to discover both coding and miRNA cancer drivers at individual level.

RESULTS

We propose the novel method, pDriver, to discover personalised cancer drivers. pDriver includes two stages: (1) Constructing gene networks for each cancer patient and (2) Discovering cancer drivers for each patient based on the constructed gene networks. To demonstrate the effectiveness of pDriver, we have applied it to five TCGA cancer datasets and compared it with the state-of-the-art methods. The result indicates that pDriver is more effective than other methods. Furthermore, pDriver can also detect miRNA cancer drivers and most of them have been confirmed to be associated with cancer by literature. We further analyse the predicted personalised drivers for breast cancer patients and the result shows that they are significantly enriched in many GO processes and KEGG pathways involved in breast cancer.

AVAILABILITY AND IMPLEMENTATION

pDriver is available at https://github.com/pvvhoang/pDriver.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Network based multifactorial modelling of miRNA-target interactions

Competing endogenous RNA (ceRNA) regulations and crosstalk between various types of non-coding RNA in humans is an important and under-explored subject. Several studies have pointed out that an alteration in miRNA:target interaction can result in unexpected changes due to indirect and complex interactions. In this article, we defined a new network-based model that incorporates miRNA:ceRNA interactions with expression values. Our approach calculates network-wide effects of perturbations in the expression level of one or more nodes in the presence or absence of miRNA interaction factors such as seed type, binding energy. We carried out the analysis of large-scale miRNA:target networks from breast cancer patients. Highly perturbing genes identified by our approach coincide with breast cancer-associated genes and miRNAs. Our network-based approach takes the sponge effect into account and helps to unveil the crosstalk between nodes in miRNA:target network. The model has potential to reveal unforeseen regulations that are only evident in the network context. Our tool is scalable and can be plugged in with emerging miRNA effectors such as circRNAs, lncRNAs, and available as R package ceRNAnetsim: https://www.bioconductor.org/packages/release/bioc/html/ceRNAnetsim.html.

The overexpression of DNA repair genes in invasive ductal and lobular breast carcinomas: Insights on individual variations and precision medicine

In the era of precision medicine, analyzing the transcriptomic profile of patients is essential to tailor the appropriate therapy. In this study, we explored transcriptional differences between two invasive breast cancer subtypes; infiltrating ductal carcinoma (IDC) and lobular carcinoma (LC) using RNA-Seq data deposited in the TCGA-BRCA project. We revealed 3854 differentially expressed genes between normal ductal tissues and IDC. In addition, IDC to LC comparison resulted in 663 differentially expressed genes. We then focused on DNA repair genes because of their known effects on patients' response to therapy and resistance. We here report that 36 DNA repair genes are overexpressed in a significant number of both IDC and LC patients' samples. Despite the upregulation in a significant number of samples, we observed a noticeable variation in the expression levels of the repair genes across patients of the same cancer subtype. The same trend is valid for the expression of miRNAs, where remarkable variations between patients' samples of the same cancer subtype are also observed. These individual variations could lie behind the differential response of patients to treatment. The future of cancer diagnostics and therapy will inevitably depend on high-throughput genomic and transcriptomic data analysis. However, we propose that performing analysis on individual patients rather than a big set of patients' samples will be necessary to ensure that the best treatment is determined, and therapy resistance is reduced.

Let-7d and miR-185 Impede Epithelial-Mesenchymal Transition by Downregulating Rab25 in Breast Cancer

Objective:

MicroRNAs (miRNAs) expression has deregulated in several cancer types including breast cancer (BC). The present study aims at investigating the role, mechanism, clinical value of let-7d and miR-185 in BC, and the possible correlation these miRNAs with Rab25.

Materials and Methods:

Tumor samples as well adjacent normal tissues (ANT) were acquired from fresh surgical specimens from 110 patients and the expression levels of let-7d, miR-185, Rab25, and snail were evaluated using real-time PCR. The immunohistochemical (IHC) process and western blot were done to detect the level of Rab25 and Snail protein expression in BC samples.

Results:

By comparing miRNAs expression profiles in clinical tissues of 110 patients using real-time PCR, let-7d, and miR-185 expression were dramatically downregulated in BC tissues (P < 0.05). Tumor size, stage, and lymph node metastasis were significantly related to miRNAs expression. Based on qRT-PCR and bioinformatics database analyses, we also recognized Rab25 as a possible target of miR-185 and let-7d. Rab25 expression was enhanced in BC cells and associated inversely with the expression level of mentioned miRNAs. qRT-PCR, immunohistochemistry, and western blot studies verified that Rab25 upregulation increased the levels of the snail, that key transcription factor of epithelial-mesenchymal transition (EMT).

Conclusion:

These findings demonstrated that let-7d and miR-185 inhibited EMT by targeting Rab25 expression in BC. Therefore, targeting the let-7d and miR-185/Rab25 interaction may offer new therapeutic opportunities for treating BC patients.

CXCL5 contributes to the tumorigenicity of cervical cancer and is post-transcriptionally regulated by miR-577

BACKGROUND

C-X-C motif chemokine ligand 5 (CXCL5), an important chemokine, has been validated to promote human tumorigenesis. However, the clinical significance and the underlying molecular mechanisms of CXCL5 have not been completely explored in cervical cancer. Herein, the aim was to investigate miR-577-mediated CXCL5 signaling in cervical tumorigenicity.

MATERIAL AND METHODS

Sixty-one pairs of cervical cancer specimens and para-carcinoma tissues were collected to measure miR-577 and CXCL5 expression levels. miR-577 mimics and/or si-CXCL5 were transfected into cervical cancer cell lines, Hela, and SiHa cells, to determine their effect on cell proliferation, migration and apoptosis.

RESULTS

Our results demonstrated that CXCL5 is overexpressed in cervical cancer tissues and cell lines. Knockdown of CXCL5 with specific siRNA transfection in Hela and SiHa cells significantly inhibited cell proliferation and migration and induced apoptosis in vitro. We also report that CXCL5 is a direct target of miR-577. Additionally, transfection of miR-577 mimics can inhibit CXCL5 protein expression, but not mRNA in Hela cells. miR-577 mimic transfection significantly inhibits migration and induces apoptosis in Hela and SiHa cells. However, the antineoplastic activities of miR-577 are reversed by overexpression of CXCL5 in vitro.

CONCLUSIONS

Overexpression of CXCL5 is involved in tumor development of cervical cancer. Inhibition of CXCL5 by its post-transcriptional regulator, miR-577, may provide a promising therapeutic strategy for patients with cervical cancer.

Mesenchymal Transformation: The Rosetta Stone of Glioblastoma Pathogenesis and Therapy Resistance

Despite decades of research, glioblastoma (GBM) remains invariably fatal among all forms of cancers. The high level of inter- and intratumoral heterogeneity along with its biological location, the brain, are major barriers against effective treatment. Molecular and single cell analysis identifies different molecular subtypes with varying prognosis, while multiple subtypes can reside in the same tumor. Cellular plasticity among different subtypes in response to therapies or during recurrence adds another hurdle in the treatment of GBM. This phenotypic shift is induced and sustained by activation of several pathways within the tumor itself, or microenvironmental factors. In this review, the dynamic nature of cellular shifts in GBM and how the tumor (immune) microenvironment shapes this process leading to therapeutic resistance, while highlighting emerging tools and approaches to study this dynamic double-edged sword are discussed.

Pyntacle: a parallel computing-enabled framework for large-scale network biology analysis

BACKGROUND

Some natural systems are big in size, complex, and often characterized by convoluted mechanisms of interaction, such as epistasis, pleiotropy, and trophism, which cannot be immediately ascribed to individual natural events or biological entities but that are often derived from group effects. However, the determination of important groups of entities, such as genes or proteins, in complex systems is considered a computationally hard task.

RESULTS

We present Pyntacle, a high-performance framework designed to exploit parallel computing and graph theory to efficiently identify critical groups in big networks and in scenarios that cannot be tackled with traditional network analysis approaches.

CONCLUSIONS

We showcase potential applications of Pyntacle with transcriptomics and structural biology data, thereby highlighting the outstanding improvement in terms of computational resources over existing tools.

LINC01094/miR-577 axis regulates the progression of ovarian cancer

Background

Long intergenic non-coding RNA 01094 (LINC01094) is probably a novel regulator in cancer biology. This study aimed to probe into the function and mechanism of LINC01094 in ovarian cancer (OC).

Methods

Quantitative real-time polymerase chain reaction (qRT-PCR) assay was utilized to measure LINC01094 and miR-577 expressions in OC tissues and cell lines. Western blot was used to examine the expressions of epithelial-mesenchymal transition (EMT)-related proteins, β-catenin, c-Myc and cyclin D1. Cell counting kit-8 (CCK-8) and Transwell assays were used to detect the proliferation, migration and invasion of SKOV3 and 3AO cells, respectively. Eventually, dual-luciferase reporter gene assay was employed to detect the regulatory relationship between miR-577 and LINC01094.

Results

LINC01094 expression was elevated in OC tissues and cell lines. High LINC01094 expression was associated with higher FIGO stage, lymph node metastasis and the shorter overall survival rate in patients with OC. Meanwhile, LINC01094 knockdown inhibited OC cell proliferation, migration, invasion and EMT. In addition, miR-577 was demonstrated to be a direct downstream target of LINC01094 in OC and inhibition of miR-577 reversed the biological effects of LINC01094 knockdown on OC cells. Additionally, LINC01094 / miR-577 axis regulated the expressions of β-catenin, c-Myc and cyclin D1 in OC cells.

Conclusion

LINC01094 promotes the proliferation, migration, invasion and EMT of OC cells by adsorbing miR-577.

MiR-429 suppresses proliferation and invasion of breast cancer via inhibiting the Wnt/β-catenin signaling pathway

Background

microRNAs (miRNAs) have been verified as molecular targets for regulating tumor proliferation, invasion, and metastasis in tumor progression. However, the relationship between miRNAs and cellular energy metabolism in breast cancer still needs to be clarified. This study aimed to investigate the role of miR‐429 in breast cancer progression.

Methods

Bioinformatic analyses were employed to detect the relationship between miR‐429 and cancer‐related signaling pathways. We used a Kaplan‐Meier curve to analyze survival rate in patients with high or low expression of miR‐429. We used real‐time quantitative PCR (RT‐qPCR) to detect the expression of miR‐429 in different cell lines. Sh‐con, over‐miR‐429, miR‐429 inhibitor, and sh‐inhibitor control were transfected. Colony formation and EDU assay were used to detect the proliferation of transfected cells. Wound healing and transwell assays were performed to detect the mobility and invasion ability of transfected cells. Western blot assay was used to detect relative protein expression in transfected cells and different tissues. Bioinformatic analyses were conducted to detect the target proteins expression in different breast cancer databases. Dual luciferase reporter assay was used to confirm the binding site between miR‐429 and fibronectin 1 (FN1).

Results

The results of our study indicate that MiR‐429 and its target genes are associated with cancer‐related signaling pathways and that higher miR‐429 expression corresponds with a better prognosis. When miR‐429 was overexpressed, the proliferation, invasion of MDA‐MB‐231 were inhibited. MiR‐429 was able to suppress the Wnt/β‐catenin signaling pathway, and FN1 overexpression could rescue the influence of over‐miR‐429.

Conclusions

The results of our study suggest that miR‐429 suppresses the proliferation and invasion of breast cancer via inhibiting the Wnt/β‐catenin signaling pathway.

MicroRNA-200c promotes tumor cell proliferation and migration by directly targeting dachshund family transcription factor 1 by the Wnt/β-catenin signaling pathway in nasopharyngeal carcinoma

The purpose of the present study was to determine the crucial role of microRNAs (miRNAs/miRs) involved in the proliferation and migration of nasopharyngeal carcinoma (NPC) and to investigate their underlying mechanisms. In this study, we focused on the expression and function of miR-200c in NPC. First, we found the expression level of miR-200c in NPC cells and tissues was upregulated, and it was suggested that the high expression of miR-200c accelerated the proliferation and migration of NPC cells in vitro. Notably, a result of the present study was that the cell fate determination factor dachshund family transcription factor 1 (DACH1) was identified as a direct target of miR-200c. Suppression of miR-200c expression in NPC cells increased endogenous DACH1 mRNA and protein levels, which was negatively correlated with miR-200c. Meanwhile, DACH1 was shown to regulate the Wnt/β-catenin signaling pathway. Accordingly, it was concluded that miR-200c exerted a tumor-promoting role in NPC development by targeting DACH1, which may contribute to the increase in the rates of NPC proliferation and migration. miR-200c may be a potential diagnostic and prognostic biomarker for NPC.

LIN28B/IRS1 axis is targeted by miR-30a-5p and promotes tumor growth in colorectal cancer

Insulin receptor substrate 1 (IRS1) is a potential oncogene that has been implicated in several malignant tumors. However, the regulatory mechanism of IRS1 remains to be investigated. The aim of our current study is to unveil the mechanism by which IRS1 exerts functions in tumorigenesis of colorectal cancer (CRC). The expression level of IRS1 was found to be higher in CRC cells in comparison with the normal cell. To determine the role of IRS1 in regulating CRC cellular processes, loss-of-function assays were designed and carried out in two CRC cell lines. Both in vitro and in vivo functional assays indicated that silencing of IRS1 suppressed CRC cell survival. Based on bioinformatics prediction and mechanism experiments, IRS1 was identified as a downstream target of miR-30a-5p. Furthermore, RNA-binding protein lin-28 homolog B (LIN28B) was determined to be a stabilizer of IRS1 messenger RNA. More importantly, LIN28B also acted as a target of miR-30a-5p.Through rescue assays, we proved that LIN28B-stablized IRS1 mediated miR-30a-5p-mediated CRC cell growth. In conclusion, this study revealed that LIN28B and LIN28B-stablized IRS1 promoted CRC cell growth by cooperating with miR-30a-5p.

Potential miRNAs for miRNA-Based Therapeutics in Breast Cancer

MicroRNAs (miRNAs) are small non-coding RNAs that can post-transcriptionally regulate the genes involved in critical cellular processes. The aberrant expressions of oncogenic or tumor suppressor miRNAs have been associated with cancer progression and malignancies. This resulted in the dysregulation of signaling pathways involved in cell proliferation, apoptosis and survival, metastasis, cancer recurrence and chemoresistance. In this review, we will first (i) provide an overview of the miRNA biogenesis pathways, and in vitro and in vivo models for research, (ii) summarize the most recent findings on the roles of microRNAs (miRNAs) that could potentially be used for miRNA-based therapy in the treatment of breast cancer and (iii) discuss the various therapeutic applications.

Circular RNA Circ_0016760 Modulates Non-Small-Cell Lung Cancer Growth Through the miR-577/ZBTB7A Axis

Background

Patients with locally advanced or metastatic non-small-cell lung cancer (NSCLC) have a poor prognosis. Circular RNA circ_0016760 (circ_0016760) is associated with the development of NSCLC. At present, the role and regulatory mechanism of circ_0016760 in NSCLC have not been well explained.

Methods

Quantitative real-time polymerase chain reaction (qRT-PCR) was executed to detect the expression of circ_0016760, miR-577, and Zinc finger and BTB domain containing 7A (ZBTB7A) mRNA in NSCLC tissues and cells. The colony formation, migration, invasion, and extracellular acidification rate (ECAR) of NSCLC cells were determined through colony formation, transwell, or ECAR assays. The relationship between circ_0016760 or ZBTB7A and miR-577 was analyzed via dual-luciferase reporter and RNA pull-down or RNA immunoprecipitation (RIP) assays. Protein level of ZBTB7A was evaluated with Western blot analysis. Xenograft assay was conducted to confirm the role of circ_0016760 in vivo.

Results

Circ_0016760 and ZBTB7A were upregulated and miR-577 was downregulated in NSCLC tissues and cells. Circ_0016760 exhaustion curbed the colony formation, migration, invasion, and ECAR of NSCLC cells in vitro and impeded tumor growth in vivo. Mechanically, circ_0016760 modulated ZBTB7A expression via sponging miR-577 in NSCLC cells. MiR-577 downregulation abolished the repressive effects of circ_0016760 silencing on colony formation, migration, invasion, and ECAR of NSCLC cells. Also, ZBTB7A upregulation overturned the repressive impacts of miR-577 elevation on colony formation, migration, invasion, and ECAR of NSCLC cells.

Conclusion

Circ_0016760 silencing impeded NSCLC advancement through regulation of the miR-577/ZBTB7A axis.

[Effects of RAB1A on the proliferation, invasion, and metastasis of tongue squamous cell carcinoma cells]

OBJECTIVE

This study aimed to investigate the molecular mechanism of RAB1A in the proliferation, invasion, and metastasis of human tongue squamous cell carcinoma.

METHODS

Western blot was used to detect the expression of RAB1A protein in human normal tongue epithelial cells (Hacat) and tongue squamous cell carcinoma Tca8113. The changes in RAB1A after plasmid transfection were also studied. The Tca8113 cells were named SiRAB1A/Tca8113 after RAB1A plasmid transfection. The expression of the epithelial-mesenchymal transition (EMT)-related markers of SiRAB1A/Tca8113 cells was also detected. CCK-8 assay was used to detect the proliferation of SiRAB1A/Tca8113 cells. Transwell and wound healing assays were used to detect the invasive and metastatic abilities of SiRAB1A/Tca8113 cells, respectively.

RESULTS

Western blot results showed that the expression of RAB1A in tongue squamous cell carcinoma cells was significantly higher than that in Hacat. RAB1A decreased significantly after SiRAB1A plasmid transfection. CCK-8 proliferation assay showed that the proliferation of SiRAB1A/Tca8113 cells also decreased significantly. Transwell and wound healing assays demonstrated that the invasive and metastatic abilities of SiRAB1A/Tca8113 cells decreased significantly, respectively. In addition, Western blot results demonstrated that RAB1A deletion significantly increased the expression of E-cadherin and inhibited the expression of Vimentin.

CONCLUSIONS

RAB1A could promote the proliferation, invasion, and metastasis of tongue squamous cell carcinoma cells.

Circular RNAs in nasopharyngeal carcinoma

BACKGROUND

Nasopharyngeal carcinoma (NPC) is a geographical distributed epithelial tumor of head and neck, which is prevalent in east Africa and Asia, especially southern China. Moreover, NPC has an unfavorable clinical effect and is prone to metastasis at an advanced stage. Although the recovery rate of patients has been improved due to concurrent chemoradiotherapy, poor curative effects and low overall survival remain key issues. The precise mechanisms and pivotal regulators of NPC remain still unclear. To improve the therapeutic efficacy, we focused on related-NPC circular RNAs (circRNAs). CircRNAs are a unique type of endogenous non-coding RNAs (ncRNAs) with a covalent closed-loop structure. Their expression is rich, stable and conservative. Different circRNA have specific tissue and developmental stages and can be detected in body fluids. In addition, circRNAs are involved in multiple pathological processes, especially in cancers. In recent years, using high-throughput indicator technology and bioinformatics technology, a large number of circRNAs have been identified in NPC cells and verified to have biological functions and mechanisms of action. This article aims to provide a retrospective review of the latest research on the proliferation and migration of related-NPC circRNA. Specifically, we focused on the roles and mechanisms of circRNAs in the development and progression of NPC.

CONCLUSION

CircRNA can act as an oncogene or tumor suppressor gene and participate in NPC progression (e.g., proliferation, apoptosis, migration, and invasion). In short, circRNAs have potential as biomarkers for the diagnosis, prognosis and treatment of NPC.

Long noncoding RNA LINC00520 accelerates progression of papillary thyroid carcinoma by serving as a competing endogenous RNA of microRNA-577 to increase Sphk2 expression

The long noncoding RNA (lncRNA) LINC00520 is an important modulator of the oncogenicity of multiple human cancers. However, whether LINC00520 is involved in the malignancy of papillary thyroid carcinoma (PTC) has not been extensively studied until recently. Therefore, the present study aimed to detect LINC00520 expression and evaluate its clinical significance in PTC. Functional experiments were conducted to test the biological role(s) and underlying mechanisms of LINC00520 in PTC progression. Reverse transcription quantitative polymerase chain reaction was performed to detect LINC00520 expression in PTC. A series of functional experiments, including Cell Counting Kit-8 assay, flow cytometry, Transwell migration assay, and tumor xenograft assay, was employed to investigate the biological roles of LINC00520 in PTC cells. High LINC00520 expression was verified in PTC tissues and cell lines, and this high expression was associated with the unfavorable clinicopathological parameters and short overall survival of patients. Functionally, LINC00520 interference resulted in a significant decrease in PTC cell proliferation, migration, and in vitro invasion and an increase in cell apoptosis. Further, its downregulation impaired tumor growth in vivo. Mechanistically, LINC00520 functioned as a competing endogenous RNA by sponging microRNA-577 (miR-577) and thereby increasing sphingosine kinase 2 (Sphk2) expression. Rescue experiments revealed that inhibiting miR-577 or restoring Sphk2 could abrogate the effects of LINC00520 silencing on the malignant phenotypes of PTC. LINC00520 functioned as an oncogenic lncRNA in PTC, and it facilitated PTC progression by regulating the miR-577/Sphk2 axis, suggesting that the LINC00520/miR-577/Sphk2 axis is an effective target in anticancer management.

TMPO-AS1 promotes cervical cancer progression by upregulating RAB14 via sponging miR-577

BACKGROUND

Accumulating evidence has shown that long non-coding RNAs play a key role in cancer initiation and development. However, the effect of TMPO antisense RNA 1 (TMPO-AS1) on the progression of cervical cancer (CC) remains to be determined.

METHODS

The mRNA expression of TMPO-AS1, miR-577 and RAB14 was measured by a quantitative reverse transcriptase-polymerase chain reaction. The protein level of RAB14 was detected by western blotting. The function of TMPO-AS1 in CC was measured via Cell Counting Kit-8, 5-ethynyl-2'-deoxyuridine and transwell assays, as well as by flow cytometry analysis. Nuclear-cytoplasmic fractionation and RNA-fluorescence in situ hybridization validated the subcellular position of TMPO-AS1. An interaction between miR-577 and TMPO-AS1 or RAB14 was confirmed by luciferase reporter, RNA pull-down and RNA immunoprecipitation assays.

RESULTS

TMPO-AS1 was highly expressed in CC. In addition, TMPO-AS1 knockdown inhibited proliferation and migration, and also induced apoptosis. TMPO-AS1 located in the cytoplasm and promoted RAB14 expression by absorbing miR-577. RAB14 overexpression or miR-577 knockdown restored the suppressing effect of TMPO-AS1 knockdown on the biological behavior of CC cells.

CONCLUSIONS

The present study has revealed a novel TMPO-AS1/miR-577/RAB14 regulatory axis in the pathogenesis of CC, highlighting TMPO-AS1 as a promising therapeutic target for CC patients.

MicroRNAs and Epigenetics Strategies to Reverse Breast Cancer

Breast cancer is a sporadic disease with genetic and epigenetic components. Genomic instability in breast cancer leads to mutations, copy number variations, and genetic rearrangements, while epigenetic remodeling involves alteration by DNA methylation, histone modification and microRNAs (miRNAs) of gene expression profiles. The accrued scientific findings strongly suggest epigenetic dysregulation in breast cancer pathogenesis though genomic instability is central to breast cancer hallmarks. Being reversible and plastic, epigenetic processes appear more amenable toward therapeutic intervention than the more unidirectional genetic alterations. In this review, we discuss the epigenetic reprogramming associated with breast cancer such as shuffling of DNA methylation, histone acetylation, histone methylation, and miRNAs expression profiles. As part of this, we illustrate how epigenetic instability orchestrates the attainment of cancer hallmarks which stimulate the neoplastic transformation-tumorigenesis-malignancy cascades. As reversibility of epigenetic controls is a promising feature to optimize for devising novel therapeutic approaches, we also focus on the strategies for restoring the epistate that favor improved disease outcome and therapeutic intervention.

Circular RNA circ_0008450 upregulates CXCL9 expression by targeting miR-577 to regulate cell proliferation and invasion in nasopharyngeal carcinoma

As a kind of malignant tumor, nasopharyngeal carcinoma (NPC) has attracted increasing attention from researchers. As a member of the circular RNA (circRNA) family, circ_0008450 has been investigated in hepatocellular carcinoma but not in NPC. This study aims to reveal the special biologic role and mechanism of circ_0008450 in NPC. qRT-PCR analysis was conducted to test the level of circ_0008450 in different tissues and cells. Loss/Gain of function assay was utilized to detect the influence of silenced/overexpressed circ_0008450 on the proliferation, apoptosis, migration, and invasion of NPC cells. The mechanism of circ_0008450 was assessed by performing qRT-PCR and luciferase reporter experiments. The results showed that circ_0008450 was elevated in NPC tissues and cells. Silenced circ_0008450 could inhibit cell proliferation, and metastatic properties and increased the number of apoptotic cells. Ectopically expressed circ_0008450 strengthened the abovementioned malignant biological behaviors. Mechanistically, circ_0008450 reduced miR-577-mediated repression of CXCL9, resulting in facilitating the oncogenic functions of NPC. In conclusion, circ_0008450 acts as an oncogene in NPC cells through regulating miR-577/CXCL9 signaling. Our findings might provide a new therapeutic target for treating NPC.

KHDRBS3 regulates the permeability of blood-tumor barrier via cDENND4C/miR-577 axis

The existence of blood–tumor barrier (BTB) severely restricts the efficient delivery of antitumor drugs to cranial glioma tissues. Various strategies have been explored to increase BTB permeability. RNA-binding proteins and circular RNAs have recently emerged as potential regulators of endothelial cells functions. In this study, RNA-binding protein KH RNA-binding domain containing, signal transduction associated 3 (KHDRBS3) and circular RNA DENND4C (cDENND4C) were enriched in GECs. KHDRBS3 bound to cDENND4C and increased its stability. The knockdown of cDENND4C increased the permeability of BTB via downregulating the expressions of tight junction-related proteins. The miR-577 was lower expressed in GECs. The overexpressed miR-577 increased the permeability of BTB by reducing the tight junction-related protein expressions, and vice versa. Furthermore, cDENND4C acted as a molecular sponge of miR-577, which bound to miR-577 and inhibited its negative regulation of target genes ZO-1, occludin and claudin-1 to regulate BTB permeability. Single or combined treatment of KHDRBS3, cDENND4C, and miR-577 effectively promoted antitumor drug doxorubicin (DOX) across BTB to induce apoptosis of glioma cells. Collectively, the present study indicated that KHDRBS3 could regulate BTB permeability through the cDENND4C/miR-577 axis, which enhanced doxorubicin delivery across BTB. These findings may provide a novel strategy for chemotherapy of brain tumors.

MicroRNA-937 inhibits the malignant phenotypes of breast cancer by directly targeting and downregulating forkhead box Q1

Purpose: Numerous microRNAs (miRNAs) are aberrantly expressed in breast cancer, and the dysregulation of miRNAs may affect the aggressiveness of this cancer. Aberrant expression of miRNA-937 (miR-937) in gastric and lung cancers has been reported, which plays tumor-suppressive or oncogenic roles in carcinogenesis including cancer progression. Our purpose was to investigate the involvement of miR-937 in breast cancer progression.

Patients and methods: The expression profile of miR-937 in breast cancer was assessed by reverse-transcription quantitative PCR. Biological effects of miR-937 upregulation on the malignant characteristics of breast cancer cells were determined in a series of functional experiments. The direct target of miR-937 in breast cancer cells was also identified.

Results: Herein, the expression levels of miR-937 were notably lower in breast cancer, and its underexpression was significantly correlated with lymph node metastasis and TNM stage. Patients with breast cancer underexpressing miR-937 showed shorter overall survival than did patients with breast cancer overexpressing miR-937. Proliferation, migration, and invasiveness of breast cancer cells were evidently suppressed by miR-937 upregulation. In addition, ectopic miR-937 expression hindered breast cancer tumor growth in vivo. Forkhead box Q1 (FOXQ1) mRNA was found to be a direct target of miR-937 in breast cancer. FOXQ1 turned out to be overexpressed in breast cancer tissues, and its overexpression negatively correlated with miR-937 expression. Moreover, silencing of FOXQ1 recapitulated the tumor-suppressive effects of miR-937 overexpression on breast cancer cells. Notably, FOXQ1 restoration abrogated the miR-937-mediated suppression of proliferation, migration, and invasiveness of breast cancer cells.

Conclusion: These results collectively revealed that miR-937 acts as a tumor suppressor in breast cancer and restrains cancer progression by directly targeting FOXQ1 mRNA. These data suggest that targeting of the novel miR-937–FOXQ1 axis is an attractive therapeutic method against breast cancer.

The relationship between microRNAs and Rab family GTPases in human cancers

microRNAs (miRNAs), as a group of noncoding RNAs, posttranscriptionally control gene expression by binding to 3'-untranslated region (3'-UTR). Ras-associated binding (Rab) proteins function as molecular switches for regulating vesicular transport, which mainly have oncogenic roles in cancer development and preventing the efficacy of chemotherapies. Increased evidence supported that miRNAs/Rabs interaction have been determined as potential therapeutics for cancer therapy. Nevertheless, instability and cross-targeting of miRNAs are main limitations of using miRNA-based therapeutic. The mutual interplay between Rabs and miRNAs has been poorly understood. In the present review, we focused on the essence and activity of these molecules in cancer pathogenesis. Also, numerous hindrances and potential methods in the expansion of miRNA as an anticancer therapeutics are mentioned.

microRNA‑577 inhibits cell proliferation and invasion in non‑small cell lung cancer by directly targeting homeobox A1

An increasing number of studies have indicated that the dysregulation of microRNAs (miRNAs/miR) is closely associated with non‑small cell lung cancer (NSCLC) development and progression by acting as tumor suppressors or oncogenes. Therefore, an in‑depth understanding of the biological roles of miRNAs in NSCLC may provide novel therapeutic methods for the treatment of patients with this disease. In the present study, reverse transcription‑quantitative polymerase chain reaction was used to detect miR‑577 expression in NSCLC tissues and cell lines. Cell Counting Kit‑8 and Transwell invasion assays were performed to determine the effects of miR‑577 on NSCLC cell proliferation and invasion. Luciferase reporter assays were used to demonstrate the relationship between miR‑577 and homeobox A1 (HOXA1) in NSCLC cells. The results revealed that miR‑577 was markedly downregulated in NSCLC tissues and cell lines. Additionally, restoration of miR‑577 expression significantly decreased the proliferation and invasion of NSCLC cells. Furthermore, miR‑577 negatively regulated HOXA1 expression in NSCLC cells by directly binding to its 3'‑untranslated region. HOXA1 was significantly upregulated in NSCLC tissues, and its upregulation was inversely correlated with miR‑577. Notably, restored HOXA1 expression abrogated the reduced proliferation and invasion of NSCLC cells caused by miR‑577 overexpression. Taken together, these results indicated that miR‑577 may have served tumor suppressive roles in NSCLC by directly targeting HOXA1. Therefore, this miRNA may be developed as a potential therapeutic target for the therapy of patients with NSCLC.

Downregulation of MiR-196b-5p impedes cell proliferation and metastasis in breast cancer through regulating COL1A1

Breast cancer is considered to be the most frequently diagnosed malignancy in women worldwide. MicroRNAs (miRNAs) play key roles in the regulation of tumor properties based on their capacity to regulate the expression of tumor-related genes. However, the involvement of miR-196b-5p in breast cancer development is largely unknown. Here, we showed that the expression levels of miR-196b-5p were significantly down-regulated in breast cancer samples and cell lines compared to the matched normal tissues and breast epithelial cell line, respectively. Notably, the expression of miR-196b-5p was negatively associated with lymph node metastasis and the progression of clinical stage in patients with breast cancer. MiR-196b-5p over-expression significantly inhibited the proliferation and migration of MDA-MB-231 and MDA-MB-468 cells in breast cancer. Furthermore, combining bioinformatics prediction and biochemical analyses, we showed that COL1A1 (collagen type I alpha 1 chain) was a direct downstream target gene of miR-196b-5p. Furthermore, overexpression of COL1A1 partly abrogated miR-196b-5p-mediated inhibition of proliferation and migration in MDA-MB-231 and MDA-MB-468 cells. Our data collectively indicate that miR-196b-5p inhibits cell growth and metastasis in breast cancer through down-regulating COL1A1, supporting the targeting of the new miR-196b-5p/COL1A1 axis as a promising effective therapeutic approach for breast cancer.