miR-129-3p, as a diagnostic and prognostic biomarker for renal cell carcinoma, attenuates cell migration and invasion via downregulating multiple metastasis-related genes

A review on the role of long non-coding RNA and microRNA network in clear cell renal cell carcinoma and its tumor microenvironment

Renal cell carcinoma (RCC) is the second lethal urogenital malignancy with the increasing incidence and mortality in the world. Clear cell renal cell carcinoma (ccRCC) is one major subtype of RCC, which accounts for about 70 to 80% of all RCC cases. Although many innovative therapeutic options have emerged during the last few decades, the efficacy of these treatments for ccRCC patients is very limited. To date, the prognosis of patients with advanced or metastatic ccRCC is still poor. The 5-year survival rate of these patients remains less than 10%, which mainly attributes to the complexity and heterogeneity of the tumor microenvironment (TME). It has been demonstrated that long non-coding RNAs (lncRNAs) perform an indispensable role in the initiation and progression of various tumors. They mostly function as sponges for microRNAs (miRNAs) to regulate the expression of target genes, finally influence the growth, metastasis, apoptosis, drug resistance and TME of tumor cells. However, the role of lncRNA/miRNA/mRNA axis in the TME of ccRCC remains poorly understood. In this review, we summarized the biological function of lncRNA/miRNA/mRNA axis in the pathogenesis of ccRCC, then discussed how lncRNA/miRNA/mRNA axis regulate the TME, finally highlighted their potential application as novel biomarkers and therapeutic targets for ccRCC.

Spectrum of microRNAs and their target genes in cancer: intervention in diagnosis and therapy

Till date, several groups have studied the mechanism of microRNA (miRNA) biogenesis, processing, stability, silencing, and their dysregulation in cancer. The miRNA coding genes recurrently go through abnormal amplification, deletion, transcription, and epigenetic regulation in cancer. Some miRNAs function as tumor promoters while few others are tumor suppressors based on the transcriptional regulation of target genes. A review of miRNAs and their target genes in a wide range of cancers is attempted in this article, which may help in the development of new diagnostic tools and intervention therapies. The contribution of miRNAs for drug sensitivity or resistance in cancer therapy and opportunities of miRNAs in cancer prognosis or diagnosis and therapy is also presented in detail.

Clinical significance of serum miR-129-5p in patients with diabetes mellitus presenting macrovascular complications

BACKGROUND

Diabetic macrovascular complications (DMCs) are the most common complications encountered during the course of diabetes mellitus (DM) with extremely high mortality rates. Therefore, there is an urgent need to identify specific and sensitive biomarkers for the early diagnosis of DMCs.

AIM

To investigate the expression and significance of serum miR-129-5p in patients with DM and macrovascular complications.

METHODS

Serum samples were collected from 36 healthy controls, 58 patients with DM presenting no macrovascular complications, and 62 patients with DMCs. The expression of miR-129-5p was detected using quantitative real-time polymerase chain reaction. Pearson’s correlation assay was performed to analyze the correlation between serum miR-129-5p levels and clinical indicators. Receiver operator characteristic (ROC) analysis was conducted to analyze the diagnostic value of serum miR-129-5p in patients with DM or DMCs.

RESULTS

There was a 4.378-fold and 7.369-fold increase in serum miR-129-5p expression in the DM (5.346 ± 0.405) and DMCs (8.998 ± 0.631) groups, respectively (P < 0.001), compared with the control group (1.221±0.090). In addition, the expression of serum miR-129-5p in patients with DMCs was higher than that in patients with DM, revealing a 1.683-fold increase (P < 0.001). Additionally, serum miR-129-5p expression significantly correlated with smoking history, disease duration, and glycated hemoglobin (HbA1c) in patients with DMCs (P < 0.001). The area under the ROC curve (AUC) of miR-129-5p as a serum marker was 0.964 (95% confidence interval [CI]: 0.930-0.997, P < 0.001) in distinguishing between patients with DM and healthy controls, whereas the AUC of miR-129-5p as a serum marker was 0.979 (95%CI: 0.959-0.999, P < 0.001) in distinguishing between patients with DMCs and healthy controls.

CONCLUSION

Elevated serum miR-129-5p expression levels correlate with the development of DMCs and can be utilized as a novel early diagnostic biomarker for DM combined with macrovascular complications.

LncRNA SNHG1 regulates immune escape of renal cell carcinoma by targeting miR-129-3p to activate STAT3 and PD-L1

Immune escape of renal cell carcinoma (RCC) impacts patient survival. However, the molecular mechanism of long noncoding RNA (lncRNA) small nucleolar RNA host gene 1 (SNHG1) in RCC immune escape remains unclear. Quantitative real-time PCR and western blotting results revealed that the expression of lncRNA SNHG1 and STAT3 were upregulated in RCC tissues and cells and that the expression of miR-129-3p was downregulated. Enzyme-linked immunosorbent assay results revealed the increased levels of immune-related factors (interferon-γ, tumour necrosis factor α, and interleukin-2) in RCC tissues. SNHG1 knockdown or miR-129-3p overexpression inhibited the proliferation and invasion of A498 and 786-O cells, while the proliferation and cytotoxicity of CD8⁺ T cells increased, which promoted the secretion of immune-related factors. STAT3 overexpression decreased the protective effect of miR-129-3p overexpression on RCC cell immune escape. In addition, miR-129-3p knockdown and STAT3 overexpression decreased the protective effect of lncRNA SNHG1 knockdown on RCC cell immune escape. In addition, PD-L1 expression was downregulated after lncRNA SNHG1 knockdown but upregulated after miR-129-3p knockdown and STAT3 overexpression. Dual-luciferase assays showed that lncRNA SNHG1 targets miR-129-3p, and miR-129-3p targets STAT3. RNA pull-down and RNA immunoprecipitation assays verified the regulatory relationship between SNHG1 and STAT3. In vivo, shSNHG1 prolonged the overall survival of RCC tumour model mice and inhibited RCC tumour growth and immune escape but increased CD8⁺ T cell infiltration in mice. Our findings provide an experimental basis for elucidating the molecular mechanisms of immune escape by RCC and reveal a novel target to treat this disease.

The Ambivalent Role of miRNAs in Carcinogenesis: Involvement in Renal Cell Carcinoma and Their Clinical Applications

The analysis of microRNA (miRNAs), small, non-coding endogenous RNA, plays a crucial role in oncology. These short regulatory sequences, acting on thousands of messenger RNAs (mRNAs), modulate gene expression at the transcriptional and post-transcriptional level leading to translational repression or degradation of target molecules. Although their function is required for several physiological processes, such as proliferation, apoptosis and cell differentiation, miRNAs are also responsible for development and/or progression of several cancers, since they may interact with classical tumor pathways. In this review, we highlight recent advances in deregulated miRNAs in cancer focusing on renal cell carcinoma (RCC) and provide an overview of the potential use of miRNA in their clinical settings, such as diagnostic and prognostic markers.

MicroRNA Signature in Renal Cell Carcinoma

Renal cell carcinoma (RCC) includes 2.2% of all diagnosed cancers and 1.8% of cancer-related mortalities. The available biomarkers or screening methods for RCC suffer from lack of sensitivity or high cost, necessitating identification of novel biomarkers that facilitate early diagnosis of this cancer especially in the susceptible individuals. MicroRNAs (miRNAs) have several advantageous properties that potentiate them as biomarkers for cancer detection. Expression profile of miRNAs has been assessed in biological samples from RCC patients. Circulatory or urinary levels of certain miRNAs have been proposed as markers for RCC diagnosis or follow-up. Moreover, expression profile of some miRNAs has been correlated with response to chemotherapy, immunotherapy or targeted therapeutic options such as sunitinib. In the current study, we summarize the results of studies that assessed the application of miRNAs as biomarkers, therapeutic targets or modulators of response to treatment modalities in RCC patients.

miR-129-3p alleviates chondrocyte apoptosis in knee joint fracture-induced osteoarthritis through CPEB1

Background

Osteoarthritis (OA), a refractory disease, is one of the leading contributors for disability worldwide. Since chondrocyte is the only resident cell in cartilage, this study aims to explore the roles of miR-129-3p and CPEB1 in chondrocyte apoptosis in knee joint fracture-induced OA.

Methods

Cartilage was collected from 20 OA patients who underwent total knee replacement (OA group) and 20 patients with knee contusion (normal group). Then, miR-129-3p and CPEB1 levels in the cartilage were quantified by qRT-PCR. Primary rat chondrocytes in the knee were isolated and identified by toluidine blue staining and immunofluorescent staining of type II collagen. OA cellular models were induced by TNF-α treatment, in which miR-129-3p and CPEB1 expressions were assessed. Subsequently, cell viability, apoptosis, and the expression levels of apoptotic protein and caspase-3 were measured. Dual luciferase reporter assay identified the interaction between miR-129-3p and CPEB1.

Results

Patients in the OA group had decreased miR-129-3p expression and increased CPEB1 expression than those in the normal group. TNF-α treatment successfully induced the OA cellular model. Downregulated miR-129-3p and upregulated CPEB1 expressions were found in OA-treated chondrocytes. miR-129-3p overexpression or CPEB1 knockdown improved chondrocyte viability and attenuated apoptosis, and vice versa. miR-129-3p negatively regulated CPEB1, thus ameliorating apoptosis and enhancing cell viability.

Conclusion

miR-129-3p negatively targeted CPEB1 to facilitate chondrocyte viability and hamper apoptosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-020-02070-1.

Renal Cell Tumors: Uncovering the Biomarker Potential of ncRNAs

Renal cell tumors (RCT) remain as one of the most common and lethal urological tumors worldwide. Discrimination between (1) benign and malignant disease, (2) indolent and aggressive tumors, and (3) patient responsiveness to a specific therapy is of major clinical importance, allowing for a more efficient patient management. Nonetheless, currently available tools provide limited information and novel strategies are needed. Over the years, a putative role of non-coding RNAs (ncRNAs) as disease biomarkers has gained relevance and is now one of the most prolific fields in biological sciences. Herein, we extensively sought the most significant reports on ncRNAs as potential RCTs' diagnostic, prognostic, predictive, and monitoring biomarkers. We could conclude that ncRNAs, either alone or in combination with currently used clinical and pathological parameters, might represent key elements to improve patient management, potentiating the implementation of precision medicine. Nevertheless, most ncRNA biomarkers require large-scale validation studies, prior to clinical implementation.

Expression of miR-129-5p and miR-433 in the serum of breast cancer patients and their relationship with clinicopathological features

Expression of miR-129-5p and miR-433 was detected in breast cancer to explore the relationship with clinicopathological features of breast cancer. Seventy-eight patients with breast cancer diagnosed in Zhengzhou Central Hospital Affiliated to Zhengzhou University (Zhengzhou, China) from February 2016 to September 2017 were collected and enrolled into the research group. Additionally, 72 healthy people who underwent physical examination during the same period were selected as the control group. The expression levels of miR-129-5p and miR-433 in peripheral blood of the two groups were detected by fluorescence quantitative PCR (RT-PCR). The relationship between the expression of miR-129-5p, miR-433 and clinicopathological features, clinical stages of breast cancer, and the degree of differentiation were analyzed. Expression of miR-129-5p and miR-433 in the research group was significantly lower than that in the control group (P<0.05). Expression of miR-129-5p in the blood of breast cancer patients was correlated with tumor size, differentiation degree, lymph node metastasis, depth of invasion and clinical stages (P<0.05). Expression level of miR-433 was correlated with the degree of differentiation, lymph node metastasis, depth of invasion and clinical stages (P<0.05). miR-129-5p and miR-433 were positively correlated with differentiation degree (r=0.8507, r=0.7522; P<0.05), and negatively correlated with clinical stages (r=−0.6595, −0.8947; P<0.05). The sensitivity and area under curve (AUC) were higher in joint detection (87.5 and 0.95% respectively), compared with those in single detection. Patients were separated into high and low expression groups according to the median values of miR-129-5p and miR-433. The one-year survival rate of breast cancer patients was analyzed. Patients in the low expression groups had lower survival rates than patients in the high expression groups (P<0.05). In conclusion, the expression of miR-129-5p and miR-433 in peripheral blood of breast cancer patients is lower than that of healthy people, and the expression level is closely related to clinical stages and differentiation degree, which is expected to provide reference value for judging the state of breast cancer patients. The combined detection of miR-129-5p and miR-433 is of great significance in the diagnosis and treatment of breast cancer.

The Prediction of miRNAs in SARS-CoV-2 Genomes: hsa-miR Databases Identify 7 Key miRs Linked to Host Responses and Virus Pathogenicity-Related KEGG Pathways Significant for Comorbidities

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a member of the betacoronavirus family, which causes COVID-19 disease. SARS-CoV-2 pathogenicity in humans leads to increased mortality rates due to alterations of significant pathways, including some resulting in exacerbated inflammatory responses linked to the “cytokine storm” and extensive lung pathology, as well as being linked to a number of comorbidities. Our current study compared five SARS-CoV-2 sequences from different geographical regions to those from SARS, MERS and two cold viruses, OC43 and 229E, to identify the presence of miR-like sequences. We identified seven key miRs, which highlight considerable differences between the SARS-CoV-2 sequences, compared with the other viruses. The level of conservation between the five SARS-CoV-2 sequences was identical but poor compared with the other sequences, with SARS showing the highest degree of conservation. This decrease in similarity could result in reduced levels of transcriptional control, as well as a change in the physiological effect of the virus and associated host-pathogen responses. MERS and the milder symptom viruses showed greater differences and even significant sequence gaps. This divergence away from the SARS-CoV-2 sequences broadly mirrors the phylogenetic relationships obtained from the whole-genome alignments. Therefore, patterns of mutation, occurring during sequence divergence from the longer established human viruses to the more recent ones, may have led to the emergence of sequence motifs that can be related directly to the pathogenicity of SARS-CoV-2. Importantly, we identified 7 key-microRNAs (miRs 8066, 5197, 3611, 3934-3p, 1307-3p, 3691-3p, 1468-5p) with significant links to KEGG pathways linked to viral pathogenicity and host responses. According to Bioproject data (PRJNA615032), SARS-CoV-2 mediated transcriptomic alterations were similar to the target pathways of the selected 7 miRs identified in our study. This mechanism could have considerable significance in determining the symptom spectrum of future potential pandemics. KEGG pathway analysis revealed a number of critical pathways linked to the seven identified miRs that may provide insight into the interplay between the virus and comorbidities. Based on our reported findings, miRNAs may constitute potential and effective therapeutic approaches in COVID-19 and its pathological consequences.

MiR-223-3p promotes cell proliferation and metastasis by downregulating SLC4A4 in clear cell renal cell carcinoma

MicroRNAs (miRNAs) are known to affect the occurrence and progression of cancer. We therefore evaluated the involvement of miR-223-3p in renal cell cancer. MiR-223-3p was highly expressed in clear cell renal cell cancer tissues. Clear cell renal cell cancer patients with higher miR-223-3p expression had higher tumor stages and grades and poorer prognoses. In renal cancer cells, overexpression of miR-223-3p enhanced cell proliferation and metastasis, while inhibition of miR-223-3p reduced the malignant capacity of the cells. MiR-223-3p was found to bind directly to solute carrier family 4, member 4 (SLC4A4) mRNA, thereby reducing SLC4A4 mRNA and protein expression. SLC4A4 overexpression restrained cell proliferation and metastasis by suppressing Kirsten rat sarcoma viral oncogene (KRAS) expression in renal cancer cells. SLC4A4 expression correlated negatively with miR-223-3p expression in patient samples. Given that miR-223-3p suppressed the SLC4A4/KRAS axis, miR-223-3p gene therapy could be an effective treatment for renal cancer.

Nomogram Based on microRNA Signature Contributes to Improve Survival Prediction of Clear Cell Renal Cell Carcinoma

Objective

Numerous microRNAs (miRNAs) have been identified in ccRCC and recommended to be used for predicting clear cell renal cell carcinoma (ccRCC) prognosis. However, it is not clear whether a miRNA-based nomogram results in improved survival prediction in patients with ccRCC.

Methods

miRNA profiles from tumors and normal tissues were downloaded from The Cancer Genome Atlas (TCGA) database and analyzed using the "limma" package. The association between differentially expressed miRNAs and patient prognosis was identified using univariate, least absolute shrinkage and selection operator (LASSO), and multivariate Cox regression analyses. Next, all patients were randomly divided into development and validation cohorts at a ratio of 1 : 1. A nomogram was established based on independent prognostic factors in the development cohort. The prognostic performance of the nomogram was validated in both cohorts using the concordance index (C-index) and calibration plots.

Results

Multivariate Cox analysis identified the 13-miRNA signature, as well as AJCC stage and age, as independent prognostic factors after adjusting for other clinical covariates. The nomogram was built based on the independent variables. In the development cohort, the C-index for the constructed nomogram to predict overall survival (OS) was 0.792, which was higher than the C-index (0.731) of the AJCC staging system and C-index (0.778) of the miRNA signature. The nomogram demonstrated good discriminative ability in the validation cohort in predicting OS, with a C-index of 0.762. The calibration plots indicated an excellent agreement between the nomogram predicted survival probability and the actual observed outcomes. Furthermore, decision curve analysis (DCA) indicated that the nomogram was superior to the AJCC staging system in increasing the net clinical benefit.

Conclusions

The novel proposed nomogram based on a miRNA signature is a more reliable and robust tool for predicting the OS of patients with ccRCC compared to AJCC staging system, thus, improving clinical decision-making.

Long noncoding RNA GAS5 silencing inhibits the expression of KCNQ3 by sponging miR-135a-5p to prevent the progression of epilepsy

Epilepsy is one of the most common neurological disorders in humans. Recently, long noncoding RNAs (lncRNAs) have been reported to be important players in neurological diseases. Herein, this study aimed to examine the effect of lncRNA GAS5 on the occurrence of epilepsy in rat and cell models of epileptic seizure. The expression of lncRNA GAS5 was measured in the established rat and cell models. The binding sites between lncRNA GAS5 and miR-135a-5p, as well as those between miR-135a-5p and 3' untranslated region of KCNQ3 were predicted by miRDB and Targetscan, separately, followed by verification using dual-luciferase reporter gene assay. The expression of miR-135a-5p was measured in response to the overexpression of lncRNA GAS5. The mRNA and protein levels of KCNQ3 were examined in response to overexpression of miR-135a-5p. Next, the latency of epilepsy and frequency of epileptic seizures were assessed in rats injected with Lv-shGAS5 and Lv-miR-135a-5p in epileptic seizure model. In the rat and cell models, lncRNA GAS5 was highly expressed when epileptic seizure was induced. The expression of miR-135a-5p was decreased by overexpression of lncRNA GAS5. Meanwhile, the mRNA and protein levels of KCNQ3 were decreased in response to knockdown of miR-135a-5p. After the treatment of Lv-shGAS5 and Lv-miR-135a-5p, the average latent period of epilepsy was prolonged and the frequency of seizures was decreased. The key findings of the present study provide evidence emphasizing that lncRNA GAS5 functions as a competitive endogenous RNA of miR-135a-5p to increase expression of KCNQ3, and lncRNA GAS5 silencing inhibited the occurrence and progression of epilepsy.

Crosstalk between the lncRNA UCA1 and microRNAs in cancer

Long non-coding RNAs (lncRNAs) are a major subset of highly conserved non-coding RNAs (ncRNAs) that consist of at least 200 nucleotides and have limited protein-coding potential. Cumulative data have shown that lncRNAs are deregulated in many types of cancer and may control pathophysiological processes of cancer at various levels, including transcription, post-transcription and translation. Recently, lncRNAs have been demonstrated to interact with microRNAs (miRNAs), another major subset of ncRNAs, which regulate physiological and pathological processes by inhibiting target mRNA translation or promoting mRNA degradation. The lncRNA urothelial carcinoma-associated 1 (UCA1) has recently gained much attention as it is overexpressed in many types of cancer and is involved in carcinogenesis. Here, we review the crosstalk between UCA1 and miRNAs during the pathogenesis of cancer, with a focus on cancer-cell proliferation, invasion, drug resistance, and metabolism.

Avenanthramide A Induces Cellular Senescence via miR-129-3p/Pirh2/p53 Signaling Pathway To Suppress Colon Cancer Growth

Cellular senescence is the state of irreversible cell cycle arrest that provides a blockade during oncogenic transformation and tumor development. Avenanthramide A (AVN A) is an active ingredient exclusively extracted from oats, which possesses antioxidant, anti-inflammatory, and anticancer activities. However, the underlying mechanism(s) of AVN A in the prevention of cancer progression remains unclear. In the current study, we revealed that AVN A notably attenuated tumor formation in an azoxymethane/dextran sulfate sodium (AOM/DSS) mouse model. AVN A treatment triggered cellular senescence in human colon cancer cells, evidenced by enlarging cellular size, upregulating β-galactosidase activity, γ-H2AX positive staining, and G1 phase arrest. Moreover, AVN A treatment significantly increased the expression of miR-129-3p, which markedly repressed the E3 ubiquitin ligase Pirh2 and two other targets, IGF2BP3 and CDK6. The Pirh2 silencing by miR-129-3p led to a significant increase in protein levels of p53 and its downstream target p21, which subsequently induced cell senescence. Taken together, our data indicate that miR-129-3p/Pirh2/p53 is a critical signaling pathway in AVN A induced cellular senescence and AVN A could be a potential chemopreventive strategy for cancer treatment.

Molecular Mechanisms in Clear Cell Renal Cell Carcinoma: Role of miRNAs and Hypermethylated miRNA Genes in Crucial Oncogenic Pathways and Processes

Clear cell renal cell carcinoma (ccRCC) is the third most common urological cancer, and it has the highest mortality rate. The increasing drug resistance of metastatic ccRCC has resulted in the search for new biomarkers. Epigenetic regulatory mechanisms, such as genome-wide DNA methylation and inhibition of protein translation by interaction of microRNA (miRNA) with its target messenger RNA (mRNA), are deeply involved in the pathogenesis of human cancers, including ccRCC, and may be used in its diagnosis and prognosis. Here, we review oncogenic and oncosuppressive miRNAs, their putative target genes, and the crucial pathways they are involved in. The contradictory behavior of a number of miRNAs, such as suppressive and anti-metastatic miRNAs with oncogenic potential (for example, miR-99a, miR-106a, miR-125b, miR-144, miR-203, miR-378), is examined. miRNAs that contribute mostly to important pathways and processes in ccRCC, for instance, PI3K/AKT/mTOR, Wnt-β, histone modification, and chromatin remodeling, are discussed in detail. We also separately consider their participation in crucial oncogenic processes, such as hypoxia and angiogenesis, metastasis, and epithelial-mesenchymal transition (EMT). The review also considers the interactions of long non-coding RNAs (lncRNAs) and miRNAs of significance in ccRCC. Recent advances in the understanding of the role of hypermethylated miRNA genes in ccRCC and their usefulness as biomarkers are reviewed based on our own data and those available in the literature. Finally, new data and perspectives concerning the clinical applications of miRNAs in the diagnosis, prognosis, and treatment of ccRCC are discussed.

The role of SOX family members in solid tumours and metastasis

Cancer is a heavy burden for humans across the world with high morbidity and mortality. Transcription factors including sex determining region Y (SRY)-related high-mobility group (HMG) box (SOX) proteins are thought to be involved in the regulation of specific biological processes. The deregulation of gene expression programs can lead to cancer development. Here, we review the role of the SOX family in breast cancer, prostate cancer, renal cell carcinoma, thyroid cancer, brain tumours, gastrointestinal and lung tumours as well as the entailing therapeutic implications. The SOX family consists of more than 20 members that mediate DNA binding by the HMG domain and have regulatory functions in development, cell-fate decision, and differentiation. SOX2, SOX4, SOX5, SOX8, SOX9, and SOX18 are up-regulated in different cancer types and have been found to be associated with poor prognosis, while the up-regulation of SOX11 and SOX30 appears to be favourable for the outcome in other cancer types. SOX2, SOX4, SOX5 and other SOX members are involved in tumorigenesis, e.g. SOX2 is markedly up-regulated in chemotherapy resistant cells. The SoxF family (SOX7, SOX17, SOX18) plays an important role in angio- and lymphangiogenesis, with SOX18 seemingly being an attractive target for anti-angiogenic therapy and the treatment of metastatic disease in cancer. In summary, SOX transcription factors play an important role in cancer progression, including tumorigenesis, changes in the tumour microenvironment, and metastasis. Certain SOX proteins are potential molecular markers for cancer prognosis and putative potential therapeutic targets, but further investigations are required to understand their physiological functions.

High expression of TAZ serves as a novel prognostic biomarker and drives cancer progression in renal cancer

Renal cell carcinomas are a group of most common renal malignancies whose clinical intervention is complicated by the lack of early diagnosis and reliable prognosis biomarkers, insensitive radiotherapy and chemotherapy and expensive molecular-targeted drugs. Transcriptional coactivator TAZ has been implicated in the formation and development of various malignancies. However, the biological characteristics and function of TAZ in renal cell carcinoma are still unclear. We attempted to evaluate the potential of TAZ as a promising diagnostic and prognostic molecular marker for renal cell carcinoma. In our study, we confirmed that TAZ was frequently elevated in renal cancer tissues and cells, consistent with the results of the publicly available cancer database. Moreover, elevated TAZ expression was positively correlated with poor overall survival time, high Fuhrman grade and distant metastasis. Our receiver operating characteristic curves analysis showed that high TAZ expression could distinguish renal cancer patients from normal persons (p < 0.0001). Kaplan-Meier curves demonstrated that high TAZ expression predicted poor overall survival (p < 0.0001). Multivariate regression analysis indicated that TAZ expression could be an independent prognostic factor (p = 0.002) in patients with renal cancer. Finally, the functional roles of TAZ knockdown were examined in renal cancer cell lines and nude mice subcutaneous tumor models. In conclusion, our results suggest that TAZ may serve as a promising diagnostic and prognostic molecular marker for patients with renal cancer. Moreover, TAZ may represent a novel clinical therapeutic target.

Upregulated microRNAs in membranous glomerulonephropathy are associated with significant downregulation of IL6 and MYC mRNAs

Membranous glomerulonephropathy (MGN) is a glomerulopathy characterized by subepithelial deposits of immune complexes on the extracapillary side of the glomerular basement membrane. Insertion of C5b-9 (complement membrane-attack complex) into the membrane leads to functional impairment of the glomerular capillary wall. Knowledge of the molecular pathogenesis of MGN is actually scanty. MicroRNA (miRNA) profiling in MGN and unaffected tissues was performed by TaqMan Low-Density Arrays. Expression of miRNAs and miRNA targets was evaluated in Real-Time polymerase chain reaction (PCR). In vitro transient silencing of miRNAs was achieved through transfection with miRNA inhibitors. Ten miRNAs (let-7a-5p, let-7b-5p, let-7c-5p, let-7d-5p, miR-107, miR-129-3p, miR-423-5p, miR-516-3p, miR-532-3p, and miR-1275) were differentially expressed (DE) in MGN biopsies compared to unaffected controls. Interleukin 6 (IL6) and MYC messenger RNAs (mRNAs; targets of DE miRNAs) were significantly downregulated in biopsies from MGN patients, and upregulated in A498 cells following let-7a-5p or let-7c-5p transient silencing. Gene ontology analysis showed that DE miRNAs regulate pathways associated with MGN pathogenesis, including cell cycle, proliferation, and apoptosis. A significant correlation between DE miRNAs and mRNAs and clinical parameters (i.e., antiphospholipid antibodies, serum creatinine, estimated glomerular filtration, proteinuria, and serum cholesterol) has been detected. Based on our data, we propose that DE miRNAs and their downstream network may be involved in MGN pathogenesis and could be considered as potential diagnostic biomarkers of MGN.

miR-29b negatively regulates MMP2 to impact gastric cancer development by suppress gastric cancer cell migration and tumor growth

MicroRNAs (miRNAs) are important regulators and associated with the development of many different types of cancer, including gastric cancer. However, their pathophysiologic role and their relevance to tumorigenesis, invasion and metastasis are still unknown. In our current study, we performed microRNA array and found that 28 of miRNAs were differentially expressed in INF type of gastric cancer. Among 28 miRNAs, miR-29b was one of the most significantly down-regulated miRNA. Further bioinformatics analysis showed that MMP2 was a potential target of miR-29b. Interestingly, luciferase analysis showed that miR-29b negatively regulates MMP2 by binding with the miRNA response element (MRE) on the 3'UTR of MMP2. In addition, overexpression of miR-29b significantly decreased the mRNA and protein level of MMP2 and the activity of MMP2 to suppress gastric cancer cell migration. Moreover, lentivirus mediated overexpression of miR-29b dramatically suppressed the ability of BGC823 cells to form colonies in vitro and their ability to develop tumor in vivo in nude mice. Finally, our qPCR and western blot analysis showed that miR-29b was significantly reduced in clinical gastric cancer tissue, whereas MMP2 protein was significantly up-regulated, suggesting that this aberrant down-regulation of miR-29b might be associated with the abnormal regulation of MMP2 and the development of gastric cancer. Significant apparent was also found between miR-29b expression and TNM staging, lymph node status, tumor differentiation and Ming classification. Together, our data suggest an important regulatory role of miR-29b in the development of gastric cancer. Thus, miR-29b and MMP2 might be important diagnostic or therapeutic targets for human tumor diseases.

Potential clinical applications of microRNAs as biomarkers for renal cell carcinoma

Introduction

Renal cell carcinoma (RCC) accounts for 3% of adult malignancies and more than 90% of kidney neoplasms. High rates of undiagnostic percutaneous kidney biopsies and difficulties in reliable pre-operative differentiation between malignant and benign renal tumors using contemporary imaging techniques result in large numbers of redundant surgeries. Absence of specific biomarkers for early detection and monitoring complicates on-time diagnosis of the disease and relapse. For the patients followed up after having a nephrectomy, a noninvasive and sensitive biomarker enabling early detection of disease relapse would be extremely useful.

Material and methods

The study is a review of recent knowledge regarding potential clinical applications of microRNAs (miRNAs) as biomarkers of RCC.

Results

MicroRNAs are essential regulators of various processes such as cell proliferation, differentiation, development and death; they have been implicated in diverse biological and pathological processes in RCC. There is a class of miRNAs that promote RCC development (oncomirs) and a class of miRNAs that negatively regulate oncogenes, suppress tumor growth and invasion, and thus could be considered treatment agents (anti-oncomirs). Separate miRNAs and specific miRNAs expression profiles have been identified, enabling early detection of the disease, prediction of response to systemic therapy, or prognostication of biological behavior of the disease.

Conclusions

The miRNA network analysis and gene profiling may help to identify the most sensible molecular signatures of RCC that can be used for diagnostic purposes, as well as poor prognosis signatures and poor therapeutic response signatures in patients who undergo systemic therapy.

Long noncoding RNA NEAT1 regulate papillary thyroid cancer progression by modulating miR-129-5p/KLK7 expression

Considering the dilemma in papillary thyroid cancer treatment, this study intended to find solution in molecular respect. By probing into lncRNA-NEAT1/miR-129-5p/KLK7 interaction, this study would provide new targets for future treatment. Microarray analysis and R language package were applied to select possible lncRNA and miRNA. Luciferase reporter assay and RNA pull-down test were employed in the detection of target relationship between lncRNA and miRNA. Clone formation assay, flow cytometry analysis, wound healing assay, and transwell assay were, respectively, used to observe effects of lncRNA NEAT1/miR-129-5p/KLK7 to papillary thyroid cancer cells. Western blot and qRT-PCR were used to validate protein expressions and mRNA expressions in PTC tissues and cells. LncRNA NEAT1 was highly expressed in PTC tissues and cell lines and could deteriorate PTC by promoting proliferation, invasion, and migration accompanied by less apoptosis. Besides, miR-129-5p/lncRNA NEAT1 were found to negatively correlate with each other by direct target relationship and their combination suppressed the progression of PTC. KLK7, a highly expressed downstream protein in PTC tissues, could be directly regulated by miR-129-5p in a negative way. KLK7 accelerated the deterioration of PTC in vitro experiments which could be reversed by sh-lnc RNA NEAT1 and miR-129-5p mimics. In vivo experiments, silence of lncRNA NEAT1 restrain tumor growth in weight and volume. In conclusion, lncRNA NEAT1 suppression could inhibit PTC progression by upregulating miR-129-5p, which suppressed KLK7 expression either in vitro or vivo experiments.

UCA1 promotes cell proliferation and invasion and inhibits apoptosis through regulation of the miR129-SOX4 pathway in renal cell carcinoma

Background

Renal cell carcinoma (RCC) is the most common cancer in kidney malignancies. UCA1 has been identified as an oncogenic lncRNA in multiple cancers, including RCC. However, the underlying molecular mechanism of UCA1 involved in RCC progression is far from being addressed.

Methods

Reverse-transcription quantitative polymerase chain reaction (RT-qPCR) assays were used to measure expressions of UCA1, miR129, and SOX4 mRNA. Western blot assays were employed to detect SOX4 protein expression. Cell proliferation, invasion, and apoptosis were assessed by CCK-8, Matrigel invasion, and annexin–fluorescein isothiocyanate (FITC) apoptosis-detection assays, respectively. The interaction between UCA1 and miR129 was demonstrated by luciferase, RNA pull-down, and RNA-immunoprecipitation (RIP) assays. Luciferase assays were also used to explore whether UCA1 was able to act as a molecular sponge of miR129 to affect the interplay of miR129 and SOX4.

Results

UCA1 expression was upregulated in RCC tissue and cells, and higher UCA1 expression was associated with advanced pathogenic status and poor prognosis of RCC patients. UCA1 knockdown suppressed proliferation and invasion and induced apoptosis in RCC cells. UCA1 inhibited miR129 expression by direct interaction in RCC cells. miR129 overexpression inhibited cell proliferation and invasion and promoted apoptosis. Moreover, miR129 downregulation abrogated UCA1 knockdown-mediated antiproliferation, anti-invasion, and proapoptosis effects in RCC cells. Furthermore, UCA1 acted as a ceRNA of miR129 to enhance target-gene SOX4 expression in RCC cells.

Conclusion

UCA1 promoted cell proliferation and invasion and inhibited apoptosis by regulating SOX4 via miR129 in RCC, offering a promising therapeutic target and prognosis marker for RCC patients.

miR-218 and miR-129 regulate breast cancer progression by targeting Lamins

Breast cancer is the most frequently diagnosed life-threatening cancer in women. Triple-negative breast cancer (TNBC) has an aggressive clinical behavior, but the treatment of TNBC remains challenging. MicroRNAs (miRNAs) have emerged as a potential target for the diagnosis, therapy and prognosis of breast cancer. However, the precise role of miRNAs and their targets in breast cancer remain to be elucidated. Here we show that miR-218 is downregulated and miR-129 is upregulated in TNBC samples and their expressions confer prognosis to patients. Gain-of-function and loss-of-function analysis reveals that miR-218 has a tumor suppressive activity, while miR-129 acts as an oncomir in breast cancer. Notably, miR-218 and miR-129 directly target Lamin B1 and Lamin A, respectively, which are also found to be deregulated in human breast tumors. Finally, we demonstrate Lamins as the major factors in reliable miR-218 and miR-129 functions for breast cancer progression. Our findings uncover a new miRNA-mediated regulatory network for different Lamins and provide a potential therapeutic target for breast cancer.

MicroRNA-Mediated Regulation of HMGB1 in Human Hepatocellular Carcinoma

High-mobility group box 1 (HMGB1) is a potential therapeutic target and novel biomarker in a variety of malignant tumors, including hepatocellular carcinoma (HCC). More recently, a number of microRNAs (miRNAs) are identified as a class of regulators for broad control of HMGB1-mediated biological actions in eukaryotic cells. In this review article we will describe representative miRNAs involved in regulating the HMGB1 signaling pathways in HCC cell lines and/or animal models. We also propose the possible mechanisms underlying the miRNA/HMGB1 axis and discuss the future clinical significance of miRNAs targeting HMGB1 molecule for HCC therapy.

Aberrant methylation-mediated silencing of microRNAs contributes to HPV-induced anchorage independence

Cervical cancer and a subset of anogenital and head-and-neck carcinomas are caused by high-risk types of the human papillomavirus (hrHPV). During hrHPV-induced malignant transformation keratinocytes become able to grow anchorage independently, a tumorigenic trait at least partly associated with inactivation of tumor suppressor genes. We used hrHPV-containing keratinocytes to investigate the role of DNA methylation-mediated silencing of microRNAs (miRNAs) in the acquisition of anchorage independence.

Anchorage dependent (n=11) and independent passages (n=19) of 4 hrHPV-immortalized keratinocyte cell lines were treated with 2′-deoxy-5-azacytidine (DAC). Genome-wide miRNA expression profiles before and after treatment were compared to identify miRNAs silenced by methylation. Bisulfite sequencing and methylation-specific PCR showed increased methylation of hsa-mir-129-2/-137/-935/-3663/-3665 and -4281 in anchorage independent HPV-transformed keratinocytes and cervical cancer cell lines. Mature miRNAs derived from hsa-mir-129-2/-137/-3663 and -3665 showed functional relevance as they decreased anchorage independence in cervical cancer cell lines. Cervical (pre)cancerous lesions demonstrated increased methylation of hsa-mir-129-2/-935/-3663/-3665 and -4281, underlining the clinical relevance of our findings.

In conclusion, methylation-mediated silencing of tumor suppressive miRNAs contributes to acquisition of an anchorage independent phenotype. This study further substantiates the importance of miRNAs during early stages of carcinogenesis and underlines their potential as both disease markers and therapeutic targets.

Methylation-mediated repression of microRNA-129-2 suppresses cell aggressiveness by inhibiting high mobility group box 1 in human hepatocellular carcinoma

Aberrant expression of microRNAs (miRNAs) and its dysfunction have been revealed as crucial modulators of cancer initiation and progression. MiR-129-2 has been reported to play a tumor suppressive role in different human malignancies. Here, we demonstrated that miR-129-2 was significantly decreased in hepatocellular carcinoma (HCC) tissues and cell lines. Furthermore, miR-129-2 was expressed at significant lower levels in aggressive and recurrent tumor tissues. Clinical analysis indicated that miR-129-2 expression was inversely correlated with venous infiltration, high Edmondson-Steiner grading and advanced tumor-node-metastasis (TNM) stage in HCC. Notably, miR-129-2 was an independent prognostic factor for indicating overall survival (OS) and disease-free survival (DFS) of HCC patients. Ectopic expression of miR-129-2 inhibited cell migration and invasion in vitro and in vivo. Furthermore, we confirmed that high mobility group box 1 (HMGB1) was a direct target of miR-129-2, and it abrogated the function of miR-129-2 in HCC. Mechanistic investigations showed that miR-129-2 overexpression inhibited AKT phosphorylation at Ser473 and decreased the expression of matrix metalloproteinase2/9 (MMP2/9). Upregulation of p-AKT abolished the decreased cell migration and invasion induced by miR-129-2 in HCC. Whereas inhibition of Akt phosphorylation significantly decreased HMGB1-enhanced HCC cell migration and invasion. Moreover, we found that miR-129-2 was downregulated by DNA methylation, and demethylation of miR-129-2 increased miR-129-2 expression in HCC cells and resulted in significant inhibitory effects on cell migration and invasion. In conclusion, miR-129-2 may serve as a prognostic indicator for HCC patients and exerts tumor suppressive role, at least in part, by inhibiting HMGB1.

The biological roles and clinical implications of microRNAs in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) accounts for about 3% of tumors in adults as well as 85% of all primary renal carcinoma. And it is the third most predominant urological carcinoma, but it has the maximum mortality rate. Early diagnosis and proper follow-up of ccRCC patients may improve the prognosis of the illness. Thus, it is imperative to understand the new biomarkers of ccRCC and study new method for the modern therapy of this deadly disease. Furthermore, a large number of microRNAs (miRNAs), small non-coding RNAs, have been relevant to tumor type, stage, or survival and miRNAs might be progressed as the markers of diagnosis or prognosis in ccRCC. A growing body of data also advised the rationality of regarding miRNAs as therapeutic targets for ccRCC treatment. In this review, we tried to summarize biogenesis of miRNAs and their expression profiles, biological roles, and clinical implications in ccRCC.

miRNAs in Prediction of Prognosis in Clear Cell Renal Cell Carcinoma

Renal cell carcinoma (RCC) is the most common type of urinary malignancy. Clear cell renal cell carcinoma (ccRCC) is the predominant RCC subtype, accounting for 70-80% of RCC. In recent years, miRNAs have been found to be closely associated with the outcome of the patients with ccRCC. In this review, we summarize recent advances in research exploring the role of miRNAs in predicting prognosis in patients with ccRCC.

MicroRNA-338-3p targets SOX4 and inhibits cell proliferation and invasion of renal cell carcinoma

MicroRNA (miR)-338-3p has been reported to be involved in tumor progression and development in various types of cancer. However, the biological function of miR-338-3p and its related molecular pathways involved in the progression of renal cell carcinoma (RCC) are unknown. The present study aimed to investigate the biological role and underlying mechanism of miR-338-3p in RCC cells. It was demonstrated that miR-338-3p expression level was significantly downregulated (P<0.05) in RCC tissues and cell lines. Clinical association analysis indicated that low expression of miR-338-3p was significantly associated with advanced TNM stage and lymph node metastasis (P<0.05). Function assays revealed that restoration of miR-338-3p in RCC cells significantly inhibited cell proliferation, colony formation, migration and invasion (P<0.05). Notably, sex-determining region Y-box 4 (SOX4) was identified as a direct target of miR-338-3p in RCC cells through a luciferase reporter assay, reverse transcription-quantitative polymerase chain reaction and western blot analysis. Furthermore, SOX4 overexpression partially rescued miR-338-3p-mediated inhibition of cell proliferation, colony formation, migration and invasion in RCC cells. These results suggested that miR-338-3p functioned as a tumor suppressor in RCC cells by modulating SOX4, suggesting that miR-338-3p may have a potential use in the treatment of RCC.

Overexpression of SOX4 promotes cell migration and invasion of renal cell carcinoma by inducing epithelial-mesenchymal transition

Incomplete understanding remains in the molecular mechanisms underlying progression and metastasis of renal cancer. The transcription factor SOX4 is upregulated in various human malignancies, including renal cancer, indicating it may be involved in renal tumorigenesis. In this study, we explored this hypothesis by loss-of-function and gain-of-function assays of SOX4 in renal cancer cell lines and renal epithelial cell line. We found that specific knockdown of SOX4 in renal cancer cell lines significantly suppressed the migration and invasion of cancer cells; specific overexpression of SOX4 in renal epithelial cell line markedly promoted the migration and invasion of the cell line. Epithelial-mesenchymal transition (EMT), a fundamental morphogenesis process, is implicated in renal cancer progression and metastasis. Our results demonstrated that SOX4 positively regulated the expression of mesenchymal cell markers and negatively regulated the expression of epithelial cell marker, and was involved in signal transduction pathway of TGFβ-induced EMT. In addition, SOX4 induced EMT probably through modulating the AKT/p-AKT signaling cascade. Finally, we found that SOX4 was significantly upregulated in clinical renal cancer samples compared with corresponding normal tissues and associated with EMT process in clinical samples. Taken together, our findings confirm a crucial function of SOX4 in the metastasis of renal cancer through orchestrating EMT and establish that the function suppression of SOX4-AKT-EMT axis might be an attractive therapeutic intervention during renal cancer metastasis.

Hydrogen sulfide alleviates hypertensive kidney dysfunction through an epigenetic mechanism

Hypertension is a major risk factor for chronic kidney disease (CKD), and renal inflammation is an integral part in this pathology. Hydrogen sulfide (H₂S) has been shown to mitigate renal damage through reduction in blood pressure and ROS; however, the exact mechanisms are not clear. While several studies have underlined the role of epigenetics in renal inflammation and dysfunction, the mechanisms through which epigenetic regulators play a role in hypertension are not well defined. In this study, we sought to identify whether microRNAs are dysregulated in response to angiotensin II (ANG II)-induced hypertension in the kidney and whether a H₂S donor, GYY4137, could reverse the microRNA alteration and kidney function. Wild-type (C57BL/6J) mice were treated without or with ANG II and GYY4137 for 4 wk. Blood pressure, renal blood flow, and resistive index (RI) were measured. MicroRNA microarrays were conducted and subsequent target prediction revealed genes associated with a proinflammatory response. ANG II treatment significantly increased blood pressure, decreased blood flow in the renal cortex, increased RI, and reduced renal function. These effects were ameliorated in mice treated with GYY4137. Microarray analysis revealed downregulation of miR-129 in ANG II-treated mice and upregulation after GYY4137 treatment. Quantitation of proteins involved in the inflammatory response and DNA methylation revealed upregulation of IL-17A and DNA methyltransferase 3a, whereas H₂S production enzymes and anti-inflammatory IL-10 were reduced. Taken together, our data suggest that downregulation of miR-129 plays a significant role in ANG II-induced renal inflammation and functional outcomes and that GYY4137 improves renal function by reversing miR-129 expression.NEW & NOTEWORTHY We investigated epigenetic changes that occur in the hypertensive kidney and how H₂S supplementation reverses adverse effects. Inflammation, aberrant methylation, and dysfunction were observed in the hypertensive kidney, and these effects were alleviated with H₂S supplementation. We identify miR-129 as a potential regulator of blood pressure and H₂S regulation.

MicroRNA-30e-3p inhibits cell invasion and migration in clear cell renal cell carcinoma by targeting Snail1

Clear cell renal cell carcinoma (ccRCC) is the most common type of neoplasm affecting the adult kidney. Previous studies on ccRCC have focused on microRNAs, a class of small non-coding RNAs that are important in cancer development and progression. The present study aimed to investigate the potential role of microRNA (miR)-30e-3p in ccRCC. The results revealed that overexpression of miR-30e-3p in the A498 and 786O ccRCC cell lines was able to inhibit cell invasion and migration. The expression level of Snail1, a potential target gene of miR-30e-3p, was inversely correlated with miR-30e-3p expression in ccRCC tissues and cell lines. Furthermore, Snail1 was revealed to be directly regulated by miR-30e-3p and had an important role in mediating the biological effects of miR-30e-3p in ccRCC. Restoration of Snail1 expression was able to reverse the inhibitory properties of miR-30e-3p. Therefore, the results of the current study suggest that miR-30e-3p exerts its anticancer functions through direct targeting of Snail1 in ccRCC cells, and may be a novel therapeutic agent for this form of cancer.

miR-129 predicts prognosis and inhibits cell growth in human prostate carcinoma

MicroRNAs (miRNAs) are a class of small, well-conserved, non-coding RNAs that are increasingly identified as diagnostic and prognostic biomarkers in a number of cancers. Deregulated miR-129 is closely associated with tumorigenesis and cancer progression. However, the potential role of miR-129 in prostate cancer remains largely elusive. The present study investigated the role of miR-129 as a prognostic biomarker for tumor progression and clinical prognosis in prostate cancer patients. The examined prostate cancer tissues exhibited a significant reduction in miR-129 expression compared with the normal tissues (P=0.013). The expression levels of miR-129 were negatively correlated with histological grade (P<0.001), high preoperative prostate-specific antigen serum levels (P<0.001), pathological stage (P<0.001), high Gleason score (P<0.001), lymph node metastasis (P=0.002), angiolymphatic invasion (P=0.018), and biochemical recurrence (BCR; P=0.001). Use of the Kaplan-Meier analysis demonstrated that low miR-129 expression was closely associated with poorer BCR-free survival. Multivariate survival analysis indicated that miR-129 expression may be an independent prognostic marker for BCR-free survival in prostate cancer patients (P<0.001). Overexpression of miR-129 markedly attenuated prostate cancer cell growth by rescuing cell cycle-regulated protein expression. The present study suggests that miR-129 is downregulated in the cancerous tissues of prostate cancer patients, which was associated with poor BCR-free survival. Thus, it may be considered as a novel independent prognostic biomarker for prostate cancer. In addition, downregulation of miR-129 may serve a critical role in the proliferation of prostate cancer cells.

MicroRNAs as prognostic molecular signatures in renal cell carcinoma: a systematic review and meta-analysis

This is a systematic review of studies investigating the prognostic value of different microRNAs (miRs) in renal cell carcinoma (RCC). Twenty-seven relevant studies were identified, with a total of 2578 subjects. We found that elevated expression of miR-21, miR-1260b, miR-210, miR-100, miR-125b, miR-221, miR-630, and miR-497 was associated with a poor prognosis in RCC patients. Conversely, decreased expression of miR-106b, miR-99a, miR-1826, miR-215, miR-217, miR-187, miR-129–3p, miR-23b, miR-27b, and miR-126 was associated with a worse prognosis. We performed meta-analyses on studies to address the prognostic value of miR-21, miR-126, miR-210, and miR-221. This revealed that elevated miR-21 expression was associated with shorter overall survival (OS; hazard ratio [HR], 2.29; 95% confidence interval [CI], 1.28–4.08), cancer specific survival (CSS; HR, 4.16; 95% CI, 2.49–6.95), and disease free survival (DFS; HR, 2.15; 95% CI, 1.16–3.98). The decreased expression of miR-126 was associated with shorter CSS (HR, 0.35; 95% CI, 0.15–0.85), OS (HR, 0.45; 95% CI, 0.30–0.69), and DFS (HR 0.30; 95% CI, 0.18–0.50). Our comprehensive systematic review reveals that miRs, especially miR-21 and miR-126, could be promising prognostic markers and useful therapeutic targets in RCC.

miR-137 inhibits renal cell carcinoma growth in vitro and in vivo

MicroRNA (miR)-137 has been reported to be underexpressed and involved in various cell processes and to have antitumor effects in a range of tumors, but so far not in renal cell carcinoma (RCC). The aim of the present study was to investigate the clinical significance and role of miR-137 in RCC. The expression levels of miR-137 were determined by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) in 50 cases of paired RCC tissues and adjacent normal tissues, and in RCC cell lines. The role of miR-137 in the growth and survival of RCC cells was assessed with several in vitro approaches and in nude mice models. The results of the RT-qPCR showed that the miR-137 expression was downregulated in the RCC tissues and cell lines. The in vitro assay showed that ectopic expression of miR-137 robustly impaired RCC cell proliferation, migratory and invasive properties, and increased the induction of cell apoptosis properties. The in vivo assay demonstrated that enforced miR-137 suppressed tumor growth in xenograft nude mice models. In addition, miR-137 was indicated to inhibit the activation of phosphoinositide 3 kinase/protein kinase B signal pathway, which contributes to the inhibition of RCC growth. These findings indicate that miR-137 functions as tumor suppressor in RCC, suggesting that miR-137 may be a potential therapeutic target for RCC.

MicroRNA-27a functions as a tumor suppressor in renal cell carcinoma by targeting epidermal growth factor receptor

Numerous studies have suggested that microRNAs (miRNAs) are vital in the development of various types of human cancers, including renal cell carcinoma (RCC), and the regulation of tumor progression and invasion. However, the effect of miRNA-27a (miR-27a) on the tumorigenesis of RCC is unclear. The aim of the present study was to investigate the function of miR-27a and identify its possible target genes in RCC cells. In the present study, cell proliferation, migration and invasion and the percentage of apoptotic cells were detected by methylthiazol tetrazolium assays, Annexin V analysis, wound-healing assays and Transwell invasion assays. Western blot analysis was performed to validate the protein expression level and assess whether the epidermal growth factor receptor (EGFR) was a target gene of miR-27a. A tumor xenograft animal model was used to detect the role of miR-27a on RCC cell growth in vivo. The present study demonstrated that miR-27a significantly suppressed human RCC 786-O cell proliferation and induced cell apoptosis. Restoration of miR-27 also resulted in 786-O cell migration and invasion inhibition. Furthermore, upregulated miR-27a attenuated RCC tumor growth in the tumor xenograft animal model. The present results suggested that miR-27a functions as a tumor suppressor in RCC. The western blot analysis assay revealed that EGFR was a novel target of miR-27a. The growth suppression of RCC cells was attributed partly to the downregulation of the cell cycle by ERFR inhibition. The present findings may aid in the understanding of the molecular mechanism of miR-27a in the tumorigenesis of RCC, and may provide novel diagnostic and therapeutic options for RCC.

MicroRNAs in the Pathogenesis of Renal Cell Carcinoma and Their Diagnostic and Prognostic Utility as Cancer Biomarkers

Purpose

To provide information about the role of microRNAs in the pathogenesis of renal cell carcinoma (RCC) and their diagnostic and prognostic utility as cancer biomarkers.

Methods

A literature search was performed in the PubMed and Web of Science databases using the keywords “renal cancer/renal cell carcinoma/kidney cancer” and “miR*/miRNA*/microRNA*”. Articles dealing with the role of miRNAs in the pathogenesis of RCC, diagnostic miRNAs and prognostic miRNAs were separated.

Results

MiRNAs act both as oncogenes and tumor suppressors. They regulate apoptosis, cell growth, migration, invasion, proliferation, colony formation and angiogenesis through target proteins involved in several signaling pathways, and they are involved in key pathogenetic mechanisms such as hypoxia (HIF/VHL dependent) and epithelial-to-mesenchymal transition. Differentially expressed miRNAs can discriminate either tumor tissue from healthy renal tissue or different RCC subtypes. Circulating miRNAs are promissing as diagnostic biomarkers of RCC. Information about urinary miRNAs associated with RCC is sparse. Detection of a relapse is another implication of diagnostic miRNAs. The expression profiles of several miRNAs correlate with the prognosis of RCC patients. Comparison between primary tumor tissue and metastasis may help identify high-risk primary tumors. Finally, response to target therapy can be estimated thanks to differences in miRNA expression in tissue and serum of therapy-resistant versus therapy-sensitive patients.

Conclusions

Our understanding of the role of microRNAs in RCC pathogenesis has been increasing dramatically. Identification and validation of their gene targets may have direct impact on developing microRNA-based anticancer therapy. Several microRNAs can serve as diagnostic and prognostic biomarkers.

Diagnostic and prognostic accuracy of miR-21 in renal cell carcinoma: a systematic review protocol

INTRODUCTION

Renal cell carcinoma (RCC) is the most common neoplasm in adult kidneys. One of the most important unmet medical needs in RCC is a prognostic biomarker to enable identification of patients at high risk of relapse after nephrectomy. New biomarkers can help improve diagnosis and hence the management of patients with renal cancer. Thus, this systematic review aims to clarify the prognostic and diagnostic accuracy of miR-21 in patients with RCC.

METHODS AND ANALYSIS

We will include observational studies evaluating the diagnostic and prognostic roles of miR-21 in patients with renal cancer. The index test and reference standards should ideally be performed on all patients. We will search PubMed, SCOPUS and ISI Web of Science with no restriction of language. The outcome will be survival measures in adult patients with RCC. Study selection and data extraction will be performed by two independent reviewers. QUADAS-1 will be used to assess study quality. Publication bias and data synthesis will be assessed by funnel plots and Begg's and Egger's tests using Stata software V.11.1.

ETHICS AND DISSEMINATION

No ethical issues are predicted. These findings will be published in a peer-reviewed journal and presented at national and international conferences.

TRAIL REGISTRATION NUMBER

This systematic review protocol is registered in the PROSPERO International Prospective Register of Systematic Reviews, registration number CRD42015025001.

MiR-129-3p promotes docetaxel resistance of breast cancer cells via CP110 inhibition

Docetaxel is commonly used as an effective chemotherapeutic agent in breast cancer treatment, but the underlying mechanisms of drug resistance are not fully understood. The purpose of this study was to investigate the possible role of miR-129-3p in breast cancer cell resistance to docetaxel. MiR-129 and miR-129-3p inhibitor were transfected into breast cancer cells to investigate their effects on chemoresistance to docetaxel. The function of miR-129-3p was evaluated by apoptosis, cell proliferation, and cell cycle assays. We found that miR-129-3p was up-regulated in MDA-MB-231/Doc cells, concurrent with CP110 down-regulation, compared to the parental MDA-MB-231 cells. In vitro drug sensitivity assays demonstrated that miR-129-3p inhibition sensitized MDA-MB-231/Doc and MCF-7 cells to docetaxel, whereas miR-129 overexpression enhanced MDA-MB-231 and MCF-7 cell resistance to docetaxel. Ectopic miR-129 expression reduced CP110 expression and the luciferase activity of a CP110 3′ untranslated region-based reporter construct in MDA-MB-231 cells, suggesting that CP110 is a direct miR-129-3p target. We demonstrated that restoration of CP110 expression in MDA-MB-231 and MCF-7 cells by miR-129 overexpression rendered the cells sensitive to docetaxel. In a nude xenograft model, miR-129 up-regulation significantly decreased MDA-MB-231 cells’ response to docetaxel. Our findings suggest that miR-129-3p down-regulation potentially sensitizes breast cancer cells to docetaxel treatment.

Diagnostic Value of MicroRNAs for Urologic Cancers: A Systematic Review and Meta-Analysis

MicroRNAs (miRNAs), particularly those extracted from the blood or tissues, have become the focus of urologic cancers research. However, the literature reviews on the accuracy of miRNA detection in urologic cancers have been inconsistent, leading us to perform this meta-analysis. Eligible studies were searched in PubMed and other databases. To calculate the pooled detection accuracy estimates, we used a bivariate random-effects meta-analysis model. According to the exclusion and inclusion criteria, 41 studies were included. Overall, the results showed sensitivity of 0.77 (95% CI: 0.74-0.80) and specificity of 0.76 (95% CI: 0.72-0.79), with an area under the SROC curve (AUC) of 0.83 (95% CI: 0.80-0.86). In addition, further subgroup analyses were also conducted. Firstly, the multiple miRNAs subgroup has significantly better diagnostic specificity than single miRNA subgroup among all these cancer types, while only bladder cancer (BC) and prostate cancer (PC) group with significantly greater diagnostic sensitivity with their multiple miRNA detection. Secondly, none of these cancer types showed significant differences on diagnostic sensitivity and specificity in their specimen and sample size subgroups. Thirdly, the diagnostic sensitivity between Asian (0.791, 95% CI: 0.748-0.827) and Caucasian (0.713, 95% CI: 0.666-0.756) in BC type was shown significant different with the P-value of 0.011. The results of our study suggested that miRNAs, particularly the multiple miRNAs, may play an important role in diagnosis and monitoring of the urologic cancers as superior biomarkers.

Screening of potential biomarkers for chemoresistant ovarian carcinoma with miRNA expression profiling data by bioinformatics approach

The aim of the present study was to screen out the biomarkers associated with chemoresistance in ovarian carcinomas and to investigate the molecular mechanisms. microRNA (miRNA) expression data was obtained from published microarray data of the GSE43867 dataset from Gene Expression Omnibus (GEO), including the data of 86 chemotherapy-treated patients with serous epithelial ovarian carcinomas (response group, 36 complete response cases and 12 partial response cases; non-response group, 10 stable cases and 28 progressive disease cases), and identification of differentially-expressed miRNAs were conducted with a GEO2R online tool based on R language. TargetScan 6.2 was used to predict the targets of differentially-expressed miRNAs. Protein-protein interaction network analysis was conducted by STRING 9.1, while functional enrichment [Gene Ontology (GO) biological process terms] and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted by GeneCodis3 for the target genes. A total of 6 differentially-expressed miRNAs were screened out, with 317 target genes obtained. It was found that 67 interactions existed among 76 genes/proteins through the PPI network analysis, and that 6 of these were potential key genes (PIK3R5, MAPK3, PTEN, S1PR3, BDKRB2 and NCBP2). The main biological processes involved in chemoresistant ovarian carcinoma were apoptosis, programmed cell death, cell migration, cell death and cell motility. The miRNA target genes were found to be associated with the ErbB signaling pathway, the gonadotropin-releasing hormone signaling pathway and other pathways in cancer. IK3R5, MAPK3 and PIK3R5 are involved in the majority of GO terms and KEGG pathways associated with chemoresistance in ovarian carcinoma.

Role of MicroRNAs in Renin-Angiotensin-Aldosterone System-Mediated Cardiovascular Inflammation and Remodeling

MicroRNAs are endogenous regulators of gene expression either by inhibiting translation or protein degradation. Recent studies indicate that microRNAs play a role in cardiovascular disease and renin-angiotensin-aldosterone system- (RAAS-) mediated cardiovascular inflammation, either as mediators or being targeted by RAAS pharmacological inhibitors. The exact role(s) of microRNAs in RAAS-mediated cardiovascular inflammation and remodeling is/are still in early stage of investigation. However, few microRNAs have been shown to play a role in RAAS signaling, particularly miR-155, miR-146a/b, miR-132/122, and miR-483-3p. Identification of specific microRNAs and their targets and elucidating microRNA-regulated mechanisms associated RAS-mediated cardiovascular inflammation and remodeling might lead to the development of novel pharmacological strategies to target RAAS-mediated vascular pathologies. This paper reviews microRNAs role in inflammatory factors mediating cardiovascular inflammation and RAAS genes and the effect of RAAS pharmacological inhibition on microRNAs and the resolution of RAAS-mediated cardiovascular inflammation and remodeling. Also, this paper discusses the advances on microRNAs-based therapeutic approaches that may be important in targeting RAAS signaling.

The role of epigenetics in kidney malignancies

Introduction

Renal cell carcinomas (RCC) are collectively the third most common type of genitourinary neoplasms, surpassed only by prostate and bladder cancer. Cure rates for renal cell carcinoma are related to tumor grade and stage; therefore, diagnostic methods for early detection and new therapeutic modalities are of paramount importance. Epigenetics can be defined as inherited modifications in gene expression that are not encoded in the DNA sequence itself. Epigenetics may play an important role in the pursuit of early diagnosis, accurate prognostication and identification of new therapeutic targets.

Material and methods

We used PubMed to conduct a comprehensive search of the English medical literature using search terms including epigenetics, DNA methylation, histone modification, microRNA regulation (miRNA) and RCC. In this review, we discuss the potential application of epigenetics in the diagnosis, prognosis and treatment of kidney cancer.

Results

During the last decade, many different types of epigenetic alterations of DNA have been found to be associated with malignant renal tumors. This has led to the research of the diagnostic and prognostic implications of these changes in renal malignancies as well as to the development of novel drugs to target these changes, with the aim of achieving a survival benefit.

Conclusions

Epigenetics has become a promising field in cancer research. The potential to achieve early detection and accurate prognostication in kidney cancer might be feasible through the application of epigenetics. The possibility to reverse these epigenetic changes with new therapeutic agents motivates researchers to continue pursuing better treatment options for kidney cancer and other malignancies.

MiR-129-2 functions as a tumor suppressor in glioma cells by targeting HMGB1 and is down-regulated by DNA methylation

MicroRNA (miRNA) dysregulation is causally related to cancer development and progression, and recent reports have revealed that DNA methylation constitutes an important mechanism for miRNA deregulation in cancer. MiR-129-2 has been reported to be down-regulated and functions as a tumor suppressor in a few human cancers. However, the involvement of miR-129-2 in the pathology of glioma and the mechanism underlying miR-129-2 regulation in glioma cells remain unclear. In this study, we performed quantitative PCR to investigate the level of miR-129-2 in 21 pairs of glioma tumors and matched adjacent tissues and found that miR-129-2 is down-regulated in glioma tumors. In vitro cell growth, apoptosis, cell migration, and invasion assays revealed that miR-129-2 functions as a tumor suppressor in glioma cells. Luciferase reporter assay found that miR-129-2 could directly target high-mobility group box 1 (HMGB1) and inhibit its expression in glioma cells. Methylation-specific PCR found that DNA methylation in upstream regions of miR-129-2 occured more frequently in cancer tissues than in adjacent tissues. Demethylation of miR-129-2 by 5-aza-2'-deoxycytidine treatment and quantitative PCR analysis revealed that miR-129-2 expression is epigenetically regulated in glioma cells. Taken together, our data suggested that miR-129-2 functions as a tumor suppressor in glioma cells by directly targeting HMGB1 and is down-regulated by DNA methylation, which may provide a novel therapeutic strategy for treatment of glioma.