MicroRNA-132 inhibits migration, invasion and epithelial-mesenchymal transition via TGFβ1/Smad2 signaling pathway in human bladder cancer

New insight in urological cancer therapy: From epithelial-mesenchymal transition (EMT) to application of nano-biomaterials

A high number of cancer-related deaths (up to 90) are due to metastasis and simple definition of metastasis is new colony formation of tumor cells in a secondary site. In tumor cells, epithelial-mesenchymal transition (EMT) stimulates metastasis and invasion, and it is a common characteristic of malignant tumors. Prostate cancer, bladder cancer and renal cancer are three main types of urological tumors that their malignant and aggressive behaviors are due to abnormal proliferation and metastasis. EMT has been well-documented as a mechanism for promoting invasion of tumor cells and in the current review, a special attention is directed towards understanding role of EMT in malignancy, metastasis and therapy response of urological cancers. The invasion and metastatic characteristics of urological tumors enhance due to EMT induction and this is essential for ensuring survival and ability in developing new colonies in neighboring and distant tissues and organs. When EMT induction occurs, malignant behavior of tumor cells enhances and their tend in developing therapy resistance especially chemoresistance promotes that is one of the underlying reasons for therapy failure and patient death. The lncRNAs, microRNAs, eIF5A2, Notch-4 and hypoxia are among common modulators of EMT mechanism in urological tumors. Moreover, anti-tumor compounds such as metformin can be utilized in suppressing malignancy of urological tumors. Besides, genes and epigenetic factors modulating EMT mechanism can be therapeutically targeted for interfering malignancy of urological tumors. Nanomaterials are new emerging agents in urological cancer therapy that they can improve potential of current therapeutics by their targeted delivery to tumor site. The important hallmarks of urological cancers including growth, invasion and angiogenesis can be suppressed by cargo-loaded nanomaterials. Moreover, nanomaterials can improve chemotherapy potential in urological cancer elimination and by providing phototherapy, they mediate synergistic tumor suppression. The clinical application depends on development of biocompatible nanomaterials.

CircRNA hsa_circ_0014130 function as a miR-132-3p sponge for playing oncogenic roles in bladder cancer via upregulating KCNJ12 expression

The modern categories of endogenous non-coding RNAs, namely circular RNAs (circRNAs), involved within the carcinogenesis and progression of various human cancers. The fundamental aim of the current investigation was the evaluation of the hsa_circ_0014130 expressions, their biological functions, and potential regulatory network in bladder cancer. The level of expression for hsa_circ_0014130 was evaluated by qRT-PCR, and its relationships to clinicopathological features and survival outcomes of cases experiencing cancer of the bladder were scrutinized. The impact of hsa_circ_0014130 expressions on biological attitudes of bladder cancer cells in vitro was investigated. The interactions between hsa_circ_0014130 and microRNA (miRNA) sponge, miRNA, and its direct targets were determined by RNA pull-down as well as luciferase reporter gene assay. The correlations of their expression were determined by Pearson's correlation analysis. Rescue experiments were carried out to identify the biological roles of the regulation network. The expressions of hsa_circ_0014130 were markedly ameliorated in bladder cancer samples and linked with aggressive characteristics and unfavorable survival. Ectopic expression of hsa_circ_0014130 clearly enhanced the differentiation, proliferative, migratory, invasive potential of the cell in bladder cancer, and the development of tumor xenograft in vivo, while malignant biological behaviors were inhibited by hsa_circ_0014130 knockdown. The expression of hsa_circ_0014130 was tied to miR-132-3p in a negative manner with the cells and tissues of bladder cancer. hsa_circ_0014130 function as a competitive endogenous RNA for miR-132-3p to play oncogenic roles in bladder cancer cells. On the other hand, KCNJ12 was a straightforward target of miR-132-3p at the downstream, and the expressions of KCNJ12 were inversely related to that of miR-132-3p. Furthermore, a significantly positive correlation was found between hsa_circ_0014130 and KCNJ12 mRNA expression. More importantly, the oncogenic impact of hsa_circ_0014130 on bladder cancer cells was partly suppressed by ectopic expression of miR-132-3p or KCNJ12 knockdown. The underlined data revealed that hsa_circ_0014130 exerted its biological roles by regulating miR-132-3p/KCNJ12 expression. Further research revealed hsa_circ_0014130/miR-132-3p/KCNJ12 axis has participated in the Epithelial-mesenchymal transition (EMT) progress and GSK3β/AKT signaling pathway. hsa_circ_0014130 works as a sponge of miR-132-3p to advance the oncogenesis and metastasis of bladder cancer by regulation of the KCNJ12 expression. These achievements might ameliorate the comprehension of tumor pathogenesis and provide novel therapeutic targets for cancer of the bladder.

Quercetin Inhibits Tumorigenesis of Colorectal Cancer Through Downregulation of hsa_circ_0006990

Quercetin can significantly inhibit the progression of colorectal cancer (CRC). However, its specific mechanism remains largely unclear. In this study, we aimed to explore the correlation among quercetin, tumour-associated macrophages (TAMs) and circular RNAs (circRNAs) in the progression of CRC and to present a novel strategy for the treatment of CRC. In this study, we revealed that quercetin could suppress the autophagy of M2-TAMs and induced their differentiation into M1-TAMs, by which quercetin significantly reversed the inhibition of M2-TAMS on CRC cell apoptosis and the promotion of M2-TAMS on CRC cell proliferation. Moreover, quercetin could promote the expression of downregulated hsa_circ_0006990 in CRC cells co-cultured with M2-TAMs, and the overexpression of hsa_circ_0006990 significantly reversed the anti-tumour effect of quercetin on CRC. Furthermore, we found quercetin can notably suppress the progression of CRC via mediation of the hsa_circ_0006990/miR-132-3p/MUC13 axis. In conclusion, our results suggested that quercetin inhibits the tumorigenesis of CRC via inhibiting the polarisation of M2 macrophages and downregulating hsa_circ_0006990. Our study provides useful insights for those exploring new methods of treating CRC.

Identification of a three-miRNA panel in serum for bladder cancer diagnosis by a diagnostic test

BACKGROUND

Bladder cancer (BC) is the tenth most common cancer in the world. Serum microRNA (miRNA) profiles previously have been reported as non-invasive biomarkers in cancer screening. The non-invasive and reliable diagnostic biomarkers are urgently needed for detecting BC, while cystoscopy is invasive. Our study aimed to identify candidate miRNAs in serum as potential diagnostic biomarkers for BC detection.

METHODS

This study was including the screening stage, training stage, and validation stage with 137 BC patients and 127 healthy controls (HCs). We identified the expression of 28 serum miRNAs from 5 BC pools and 3 HC pools in the initial screening stage. The other 112 BC patients and 112 HCs were randomly divided into training stage with 30 BC patients and 30 HCs and validation stages with 82 BC patients and 82 HCs. These HCs matched BC patients based on age and gender with P value >0.05. Identified dysregulated miRNAs were further confirmed in the training stage, and validation stages by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The diagnostic value of miRNAs was assessed by receiver operating characteristic (ROC) curves and the area under the ROC curve (AUC). Target genes of 3 candidate miRNAs were predicted by bioinformatic analysis.

RESULTS

Five miRNAs (miR-106a-5p, miR-145-5p, miR-132-3p, miR-7-5p and miR-148b-3p) in serum were obviously dysregulated in BC patients compared to HCs. The ability to diagnose BC of 3 candidate miRNAs was estimated by AUC, with miR-132-3p (AUC =0.781; sensitivity =68.29%, specificity =81.71%), miR-7-5p (AUC =0.778; sensitivity =59.76%, specificity =84.15%) and miR-148b-3p (AUC =0.837; sensitivity =81.71%, specificity =71.95%). Combined application of these candidate miRNAs with parallel test could improve the diagnostic value (AUC =0.922; sensitivity =90.24%, specificity =81.71%). BNC2, GAS7, and NTRK2, considered as target genes of the three-miRNA panel, may play an important role in the process of BC development.

CONCLUSIONS

A three-miRNA panel in serum was identified for BC diagnosis in our study, which HCs were used for differential diagnosis. The three-miRNA panel (miR-132-3p, miR-7-5p, and miR-148b-3p) might be performed as a non-invasive and convenient diagnostic tool for BC screening and diagnosis.

Oncogenic E3 ubiquitin ligase NEDD4 binds to KLF8 and regulates the microRNA-132/NRF2 axis in bladder cancer

The neuronally expressed developmentally downregulated 4 (NEDD4) gene encodes a ubiquitin ligase that targets the epithelial sodium channel for degradation and has been implicated in tumor growth in various cancers. Hence, in this study, we intended to characterize the functional relevance of the NEDD4-mediated Kruppel-like factor 8/microRNA-132/nuclear factor E2-related factor 2 (KLF8/miR-132/NRF2) axis in the development of bladder cancer. NEDD4 and KLF8 were overexpressed in bladder cancer tissues and were associated with poorer patient survival rates. In bladder cancer cells, NEDD4 intensified the stability and transcriptional activity of KLF8 through ubiquitination to augment cell viability and migratory ability. Our investigations revealed that NEDD4 promotes the binding of KLF8 to the miR-132 promoter region and inhibits the expression of miR-132. KLF8 inhibited the expression of miR-132 to augment the viability and migratory ability of bladder cancer cells. Furthermore, miR-132 downregulated the expression of NRF2 to restrict the viability and migratory ability of bladder cancer cells. In addition, in vivo findings verified that NEDD4 regulates the KLF8/miR-132/NRF2 axis by accelerating tumor growth and lung metastasis. In conclusion, this study highlights NEDD4 as a potential therapeutic target against tumor recurrence and metastasis in bladder cancer.

Circ_0000527 Drives Retinoblastoma Progression by Regulating miR-1236-3p/SMAD2 Pathway

PURPOSE

Circular RNAs (circRNAs) play essential roles in the progression of human tumors, including retinoblastoma (RB). In this study, we aimed to explore the functions and potential mechanisms of circ_0000527 in RB.

METHODS

Quantitative real-time polymerase chain reaction (qRT-PCR), Western blot assay and immunohistochemistry (IHC) assay were conducted to determine the levels of circ_0000527, microRNA-1236-3p (miR-1236-3p) and SMAD family member 2 (SMAD2). RNase R assay and actinomycin D assay were conducted to analyze the characteristic of circ_0000527. Cell Counting Kit-8 (CCK-8) assay, 5-ethynyl-2'-deoxyuridine (EdU) assay, and colony formation assay were performed for cell proliferation ability. Wound healing assay and transwell assay were applied to assess cell migration and invasion. Tube formation assay was utilized for angiogenesis ability. Flow cytometry analysis was adopted to analyze cell apoptosis. Dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were performed to analyze the relationships among circ_0000527, miR-1236-3p, and SMAD2. Murine xenograft model assay was conducted for the role of circ_0000527 in vivo.

RESULTS

Circ_0000527 was overexpressed in RB patients and related to advanced TNM stages, optic nerve invasion and choroidal invasion. Circ_0000527 knockdown suppressed cell proliferation, migration, invasion and angiogenesis and promoted apoptosis in RB cells in vitro. Circ_0000527 sponged miR-1236-3p, which directly targeted SMAD2. MiR-1236-3p level was decreased in RB tissues and cells. MiR-1236-3p inhibition reversed circ_0000527 knockdown-mediated effects on RB cell malignant behaviors. Moreover, miR-1236-3p overexpression suppressed RB cell progression, with SMAD2 elevation abrogated the effect. Additionally, circ_0000527 knockdown restrained tumor formation in vivo.

CONCLUSIONS

Circ_0000527/miR-1236-3p/SMAD2 axis played a positive role in the progression of RB.

Molecular mechanisms of the microRNA-132 during tumor progressions

Cancer as one of the leading causes of human deaths has always been one of the main health challenges in the world. Despite recent advances in therapeutic and diagnostic methods, there is still a high mortality rate among cancer patients. Late diagnosis is one of the main reasons for the high ratio of cancer related deaths. Therefore, it is required to introduce novel early detection methods. Various molecular mechanisms are associated with the tumor progression and metastasis. MicroRNAs (miRNAs) are a class of non-coding RNAs (ncRNAs) family that has important functions in regulation of the cellular processes such as cell proliferation, apoptosis, and tumor progression. Moreover, they have higher stability in body fluids compared with mRNAs which can be introduced as non-invasive diagnostic markers in cancer patients. MiR-132 has important functions as tumor suppressor or oncogene in different cancers. In the present review, we have summarized all of the studies which have been reported the role of miR-132 during tumor progressions. We categorized the miR-132 target genes based on their cell and molecular functions. Although, it has been reported that the miR-132 mainly functions as a tumor suppressor, it has also oncogenic functions especially in pancreatic tumors. MiR-132 mainly exerts its roles during tumor progressions by regulation of the transcription factors and signaling pathways. Present review clarifies the tumor specific molecular mechanisms of miR-132 to introduce that as an efficient non-invasive diagnostic marker in various cancers.

The outstanding role of miR-132-3p in carcinogenesis of solid tumors

MicroRNAs are a group of short non-coding RNAs (miRNAs), which are epigenetically involved in gene expression and other cellular biological processes and can be considered as potential biomarkers for cancer detection and support for treatment management. This review aims to amass the evidence to reach the molecular mechanism and clinical significance of miR-132 in different types of cancer. Dysregulation of miR-132 level in various types of malignancies, including hepatocellular carcinoma, breast cancer, colorectal cancer, gastric cancer, lung cancer, prostate cancer, osteosarcoma, pancreatic cancer, and ovarian cancer have reported, significantly decrease in its level, which can be indicated to its function as a tumor suppressor. miR-132 is involved in cell proliferation, migration, and invasion through cell cycle pathways, such as PI3K, TGFβ or hippo signaling pathways, or on oncogenes such as Ras, AKT, mTOR, glycolysis. miR-132 could be potentially a candidate as a valuable biomarker for prognosis in various cancers. Through this study, we proposed that miR-132 can potentially be a candidate as a prognostic marker for early detection of tumor development, progression, as well as metastasis.

MicroRNAs: Their Role in Metastasis, Angiogenesis, and the Potential for Biomarker Utility in Bladder Carcinomas

Angiogenesis is the process of generating new capillaries from pre-existing blood vessels with a vital role in tumor growth and metastasis. MicroRNAs (miRNAs) are noncoding RNAs that exert post-transcriptional control of protein regulation. They participate in the development and progression of several cancers including bladder cancer (BLCA). In cancer tissue, changes in microRNA expression exhibit tissue specificity with high levels of stability and detectability. miRNAs are less vulnerable to degradation, making them novel targets for therapeutic approaches. A suitable means of targeting aberrant activated signal transduction pathways in carcinogenesis of BLCA is possibly through altering the expression of key miRNAs that regulate them, exerting a strong effect on signal transduction. Precaution must be taken, as the complexity of miRNA regulation might result in targeting several downstream tumor suppressors or oncogenes, enhancing the effect further. Since exosomes contain both mRNA and miRNA, they could therefore possibly be more effective in targeting a recipient cell if they deliver a specific miRNA to modify the recipient cell protein production and gene expression. In this review, we discuss the molecules that have been shown to play a significant role in BLCA tumor development. We also discuss the roles of various miRNAs in BLCA angiogenesis and metastasis. Advances in the management of metastatic BLCA have been limited; miRNA mimics and molecules targeted at miRNAs (anti-miRs) as well as exosomes could serve as therapeutic modalities or as diagnostic biomarkers.

MicroRNAs and target molecules in bladder cancer

Bladder cancer (BC) is considered as one of the most common malignant tumors in humans with complex pathogenesis including gene expression variation, protein degradation, and changes in signaling pathways. Many studies on involved miRNAs in BC have demonstrated that they could be used as potential biomarkers in the prognosis, response to treatment, and screening before the cancerous phenotype onset. MicroRNAs (miRNAs) regulate many cellular processes through their different effects on special targets along with modifying signaling pathways, apoptosis, cell growth, and differentiation. The diverse expression of miRNAs in cancerous tissues could mediate procedures leading to the oncogenic or suppressor behavior of certain genes in cancer cells. Since a specific miRNA may have multiple targets, an mRNA could also be regulated by multiple miRNAs which further demonstrates the actual role of miRNAs in cancer. In addition, miRNAs can be utilized as biomarkers in some cancers that cannot be screened in the early stages. Hence, finding blood, urine, or tissue miRNA biomarkers by novel or routine gene expression method could be an essential step in the prognosis and control of cancer. In the present review, we have thoroughly evaluated the recent findings on different miRNAs in BC which can provide comprehensive information on better understanding the role of diverse miRNAs and better decision making regarding the new approaches in the diagnosis, prognosis, prevention, and treatment of BC.

miR‑132 is upregulated in polycystic ovarian syndrome and inhibits granulosa cells viability by targeting Foxa1

Polycystic ovary syndrome (PCOS) is one of the most common endocrine metabolic disorders characterized by hyperandrogenism, polycystic ovaries and ovulatory dysfunction. Several studies have suggested that the aberrant expression of microRNAs (miRNAs/miRs) plays an important role in the pathogenesis of PCOS; however, the role and underlying mechanisms of miR-132 in the development of PCOS remain unclear. In the present study, the expression of miR-132 in granulosa cells (GCs) derived from 26 patients with PCOS and 30 healthy controls was detected by reverse transcription-quantitative PCR (RT-qPCR). The apoptosis of GCs was examined using a TUNEL assay. The human ovarian granulosa-like tumor cell line, KGN, was cultured for Cell Counting Kit-8 assays following the overexpression or knockdown of miR-132. TargetScan was applied to identify the potential targets of miR-132, which was further verified by a luciferase assay, RT-qPCR and western blotting. The expression of miR-132 was decreased in GCs from patients with PCOS. Moreover, the GCs of patients with PCOS exhibited significantly increased apoptotic nuclei. Furthermore, the overexpression of miR-132 inhibited the viability of KGN cells. In addition, the results verified that miR-132 directly targeted forkhead box protein A1 (Foxa1), the knockdown of which suppressed KGN cell viability. On the whole, the findings of the present study demonstrated that miR-132 inhibited cell viability and induced apoptosis by directly interacting with Foxa1. Thus, miR-132 may be a potential target for the treatment of patients with PCOS.

lncRNA CTBP1-AS2 promotes proliferation and migration of glioma by modulating miR-370-3p-Wnt7a-mediated epithelial-mesenchymal transition

Glioma is one of the most common and aggressive malignant primary brain tumors, with a poor 5-year survival rate. The long noncoding RNA (lncRNA) CTBP1-AS2 has been shown to be correlated with the prognosis of cancer, but the role of CTBP1-AS2 in glioma and its concrete mechanism is fully unknown. The clinical data and tissues of glioma patients were analyzed. Cell viability and migration assays were performed. Western blotting and qRT-PCR were adopted for investigation of target protein expressions. Double luciferase assay was used to investigate the interaction between different elements. The lncRNA CTBP1-AS2 had increased expression profiles in tumor tissues, which is associated with poor prognosis. In detail, CTBP1-AS2 knockdown decreased proliferation and migration phenotypes in both U87-MG and LN229 cells. Moreover, CTBP1-AS2 knockdown suppressed the key epithelial-mesenchymal transition (EMT) markers by downregulating Wnt7a-mediated signaling. Furthermore, miR-370-3p functioned as a link that could be absorbed by CTBP1-AS2, thus regulating Wnt7a expression. Lastly, the CTBP1-AS2-miR-370-3p-Wnt7a axis modulated EMT in glioma cells in vitro and in vivo. This study provides new insights that a novel lncRNA, CTBP1-AS2, regulates EMT of glioma by modulating the miR-370-3p-Wnt7a axis.

MiR-132 inhibits migration and invasion and increases chemosensitivity of cisplatin-resistant oral squamous cell carcinoma cells via targeting TGF-β1

Numerous findings have demonstrated that MicroRNAs dysregulation plays a key role in many neoplasms, including oral squamous cell carcinoma (OSCC), yet the potential mechanisms of microRNAs in chemo-resistance remain elusive. Here, we analyzed the miR-132 expression in OSCC tissues and OSCC cell lines, and explored it role and mechanisms on invasion and migration and cisplatin (CDDP)-induced cell death. The clinical tissues of 37 patients with OSCCs and paired normal tissues were collected. The miR-132 expression in OSCC tissues and cell lines were detected by reverse transcription-quantitative polymerase chain reation (RT-qPCR). The in vitro repopulation models were established to mimic the biological processes of OSCC. The results showed that miR-132 expression was significantly decreased in the OSCC tissues and CDDP resistant OSCC cell line (CAL-27/CDDP). miR-132 mimic inhibited cell proliferation, invasion, migration and enhanced the pro-apoptotic ability of CDDP. On the contrary, downregulation of miR-132 promoted proliferation, invasion, migration and conferred OSCC cell resistance to CDDP-induced apoptosis in vitro. The TGF-β1 expression in OSCC tissues and CAL-27/CDDP cells was significantly higher. miR-132 significantly inhibited the TGF-β1/Smad2/3 signals. TGF-β1 upregulation significantly promoted OSCC cell proliferation and resumed OSCC cell chemo-resistance in the miR-132 overexpressing cells, which is contrary to the function of miR-132. In summary, miR-132 acts as a tumor suppressor and exerts a substantial role in inhibiting the proliferation, invasion, and enhanced the chemosensitivity to CDDP of OSCC via regulating TGF-β1/Smad2/3 signals in vitro. These observations indicate that miR-132 may be a suitable therapeutic target for the treatment of OSCC.

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

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

Long noncoding RNA NNT-AS1 enhances the malignant phenotype of bladder cancer by acting as a competing endogenous RNA on microRNA-496 thereby increasing HMGB1 expression

The long noncoding RNA nicotinamide nucleotide transhydrogenase antisense RNA 1 (NNT-AS1) is a key malignancy regulator in a variety of human cancers. In this study, we first measured the expression of NNT-AS1 in bladder cancer and examined its role in cancer progression. The mechanisms behind the oncogenic functions of NNT-AS1 in bladder cancer were explored. We found that NNT-AS1 was upregulated in bladder cancer tissues and cell lines. This increased expression demonstrated a significant correlation with advanced clinical stage, lymph node metastasis, and shorter overall survival. NNT-AS1 knockdown suppressed bladder cancer cell proliferation, migration, and invasion and facilitated apoptosis in vitro and hindered tumor growth in vivo. NNT-AS1 functioned as a competing endogenous RNA for microRNA-496 (miR-496), and the suppressive effects of NNT-AS1 knockdown on malignant characteristics were abrogated by miR-496 silencing. HMGB1 was identified as a direct target gene of miR-496 in bladder cancer, and HMGB1 expression was enhanced by NNT-AS1 via sponging of miR-496. In conclusion, the NNT-AS1–miR-496–HMGB1 pathway plays a significant role in the aggressive behavior of bladder cancer and may lead to new NNT-AS1–based diagnostics and therapeutics.