miR-329 suppresses the growth and motility of neuroblastoma by targeting KDM1A

Role of non-coding RNAs in neuroblastoma

Neuroblastoma is known as the most prevalent extracranial malignancy in childhood with a neural crest origin. It has been widely accepted that non-coding RNAs (ncRNAs) play important roles in many types of cancer, including glioma and gastrointestinal cancers. They may regulate the cancer gene network. According to recent sequencing and profiling studies, ncRNAs genes are deregulated in human cancers via deletion, amplification, abnormal epigenetic, or transcriptional regulation. Disturbances in the expression of ncRNAs may act either as oncogenes or as anti-tumor suppressor genes, and can lead to the induction of cancer hallmarks. ncRNAs can be secreted from tumor cells inside exosomes, where they can be transferred to other cells to affect their function. However, these topics still need more study to clarify their exact roles, so the present review addresses different roles and functions of ncRNAs in neuroblastoma.

CircRANBP17 modulated KDM1A to regulate neuroblastoma progression by sponging miR-27b-3p

Neuroblastoma (NB) is a common childhood cancer. Circular RNA RAN binding protein 17 (circRANBP17) has been identified to participate in diverse tumor progression. This study aims to explore the function and mechanism of circRANBP17 in NB. The levels of circRANBP17, miR-27b-3p and KDM1A in NB tissues and cells were measured by qRT-PCR. Mouse model assay was performed to investigate the effect of circRANBP17 knockdown on tumor formation in vivo. The levels of circRANBP17 and KDM1A were significantly up-regulated, and the level of miR-27b-3p was strikingly down-regulated in NB tissues and cells (SK-N-SH and SK-N-AS). Functional studies indicated that miR-27b-3p inhibitor mitigated the inhibitory effects on cell proliferation, migration, invasion and the promoting effect on cell apoptosis in SK-N-SH and SK-N-AS cells induced by circRANBP17 knockdown. Also, miR-27b-3p regulated NB cell malignancy by targeting KDM1A. Further studies revealed that miR-27b-3p inhibitor reversed the low expression of KDM1A induced by circRANBP17 knockdown. In support, circRANBP17 knockdown led to inhibition of tumor formation in vivo. In conclusion, circRANBP17 modulated KDM1A to promote cell proliferation, migration, invasion and restrain cell apoptosis in NB by sponging miR-27b-3p, and the new regulatory network may provide a theoretical basis for the further study of NB.

An overview of prostate cancer (PCa) diagnosis: Potential role of miRNAs

Prostate cancer is the second most frequently diagnosed cancer among men worldwide, with the estimated sixth leading cause of cancer death. Despite major advancements in clinical biology and imaging, digital rectal examination (DRE), prostate-specific antigen (PSA), and biopsies indication remain the keystone for screening. Several kits are used to detect genomic changes and non-coding RNAs in the sample. However, its indication remains controversial for screening purposes. There is an urged need for non-invasive biomarkers to implement precision medicine. Recent research shows that miRNAs have an important role in the diagnostic, prognostic, and therapeutic agents as non-invasive biomarkers. Though prostate cancer data remains controversial in other cancer types, such as breast cancer, miR-21 expression is upregulated. Here, we reported a prolonged revision of miRNAs as prostate cancer prognostic, diagnostic, and predictive tools, including data on androgen receptor (AR) signaling, epithelial-mesenchymal transition (EMT) process, and cancer stem cells (CSCs) regulation. The combined utilization of miRNAs with other tests will help patients and clinicians to select the most appropriate personalized treatment and to avoid overdiagnosis and unnecessary biopsies. Future clinical applications of our reported novel miRNAs have a substantial role in the primary diagnosis of prostate cancer to help treatment decisions.

Targeting Oncogenic Transcriptional Networks in Neuroblastoma: From N-Myc to Epigenetic Drugs

Neuroblastoma (NB) is one of the most frequently occurring neurogenic extracranial solid cancers in childhood and infancy. Over the years, many pieces of evidence suggested that NB development is controlled by gene expression dysregulation. These unleashed programs that outline NB cancer cells make them highly dependent on specific tuning of gene expression, which can act co-operatively to define the differentiation state, cell identity, and specialized functions. The peculiar regulation is mainly caused by genetic and epigenetic alterations, resulting in the dependency on a small set of key master transcriptional regulators as the convergence point of multiple signalling pathways. In this review, we provide a comprehensive blueprint of transcriptional regulation bearing NB initiation and progression, unveiling the complexity of novel oncogenic and tumour suppressive regulatory networks of this pathology. Furthermore, we underline the significance of multi-target therapies against these hallmarks, showing how novel approaches, together with chemotherapy, surgery, or radiotherapy, can have substantial antineoplastic effects, disrupting a wide variety of tumorigenic pathways through combinations of different treatments.

Regulation of breast cancer metastasis signaling by miRNAs

Despite the decline in death rate from breast cancer and recent advances in targeted therapies and combinations for the treatment of metastatic disease, metastatic breast cancer remains the second leading cause of cancer-associated death in U.S. women. The invasion-metastasis cascade involves a number of steps and multitudes of proteins and signaling molecules. The pathways include invasion, intravasation, circulation, extravasation, infiltration into a distant site to form a metastatic niche, and micrometastasis formation in a new environment. Each of these processes is regulated by changes in gene expression. Noncoding RNAs including microRNAs (miRNAs) are involved in breast cancer tumorigenesis, progression, and metastasis by post-transcriptional regulation of target gene expression. miRNAs can stimulate oncogenesis (oncomiRs), inhibit tumor growth (tumor suppressors or miRsupps), and regulate gene targets in metastasis (metastamiRs). The goal of this review is to summarize some of the key miRNAs that regulate genes and pathways involved in metastatic breast cancer with an emphasis on estrogen receptor α (ERα+) breast cancer. We reviewed the identity, regulation, human breast tumor expression, and reported prognostic significance of miRNAs that have been documented to directly target key genes in pathways, including epithelial-to-mesenchymal transition (EMT) contributing to the metastatic cascade. We critically evaluated the evidence for metastamiRs and their targets and miRNA regulation of metastasis suppressor genes in breast cancer progression and metastasis. It is clear that our understanding of miRNA regulation of targets in metastasis is incomplete.

Epigenetic dynamics in cancer stem cell dormancy

Cancer remains one of the most challenging diseases despite significant advances of early diagnosis and therapeutic treatments. Cancerous tumors are composed of various cell types including cancer stem cells capable of self-renewal, proliferation, differentiation, and invasion of distal tumor sites. Most notably, these cells can enter a dormant cellular state that is resistant to conventional therapies. Thereby, cancer stem cells have the intrinsic potential for tumor initiation, tumor growth, metastasis, and tumor relapse after therapy. Both genetic and epigenetic alterations are attributed to the formation of multiple tumor types. This review is focused on how epigenetic dynamics involving DNA methylation and DNA oxidations are implicated in breast cancer and glioblastoma multiforme. The emergence and progression of these cancer types rely on cancer stem cells with the capacity to enter quiescence also known as a dormant cellular state, which dictates the distinct tumorigenic aggressiveness between breast cancer and glioblastomas.

miR-152/TNS1 axis inhibits non-small cell lung cancer progression through Akt/mTOR/RhoA pathway

AIM

The purpose of the present study was to explore the function and mechanism of tensin 1 (TNS1) in non-small cell lung cancer (NSCLC) progression.

METHODS

The expression of TNS1 in NSCLC cells and tissues was assessed by RT-PCR and Western blot. Besides, Kaplan-Meier survival analysis was recruited to explore the association between TNS1 and NSCLC. Cell growth was analyzed by MTT and flow cytometry assay, while cell metastasis was determined by wound healing and transwell assays. The targeting relationship between TNS1 and miR-152 was assessed by luciferase activity assays. And Western blot was employed to determine the expression of related proteins of Akt/mTOR/RhoA pathway.

RESULTS

TNS1 level was boosted in NSCLC cells and tissues, related to the prognosis of NSCLC patients. Furthermore, it was proved that TNS1 promoted the growth and metastasis of NSCLC cells via Akt/mTOR/RhoA pathway. And miR-152 targeted TNS1 to affect the progression of NSCLC.

CONCLUSION

miR-152/TNS1 axis inhibits the progression of NSCLC by Akt/mTOR/RhoA pathway.

Neuroblastoma and the epigenome

Neuroblastoma (NB) is a pediatric cancer of the sympathetic nervous system and one of the most common solid tumors in infancy. Amplification of MYCN, copy number alterations, numerical and segmental chromosomal aberrations, mutations, and rearrangements on a handful of genes, such as ALK, ATRX, TP53, RAS/MAPK pathway genes, and TERT, are attributed as underlying causes that give rise to NB. However, the heterogeneous nature of the disease-along with the relative paucity of recurrent somatic mutations-reinforces the need to understand the interplay of genetic factors and epigenetic alterations in the context of NB. Epigenetic mechanisms tightly control gene expression, embryogenesis, imprinting, chromosomal stability, and tumorigenesis, thereby playing a pivotal role in physio- and pathological settings. The main epigenetic alterations include aberrant DNA methylation, disrupted patterns of posttranslational histone modifications, alterations in chromatin composition and/or architecture, and aberrant expression of non-coding RNAs. DNA methylation and demethylation are mediated by DNA methyltransferases (DNMTs) and ten-eleven translocation (TET) proteins, respectively, while histone modifications are coordinated by histone acetyltransferases and deacetylases (HATs, HDACs), and histone methyltransferases and demethylases (HMTs, HDMs). This article focuses predominately on the crosstalk between the epigenome and NB, and the implications it has on disease diagnosis and treatment.

Distinctive Cellular Transcriptomic Signature and MicroRNA Cargo of Extracellular Vesicles of Horse Adipose and Endometrial Mesenchymal Stem Cells from the Same Donors

Equine endometrial and adipose mesenchymal stem cells (eMSCs and aMSCs, respectively) were isolated from the same donors of thoroughbred mares. The cells displayed characteristic features of MSCs, including trilineage mesodermal and also neurogenic differentiation. We evaluated the influence of cellular origin on their transcriptome profile. Cellular RNA was isolated and sequenced and extracellular vesicles (EVs) were obtained from conditioned medium of cells cultured in medium depleted of EVs, and their microRNA (miRNA) cargo analyzed by sequencing. Differential expression of mRNAs and EV-miRNA was analyzed, as well as pathways and processes most represented in each cell origin. mRNA reads from all expressed genes clustered according to the cellular origin. A total of 125 up- and 51 downregulated genes were identified and 31 differentially expressed miRNAs. Based on mRNA sequencing, endometrial MSCs strongly upregulated genes involved in the Hippo, transforming growth factor beta, and pluripotency signaling pathways. Alongside with this, pathways involved in extracellular matrix reorganization were the most represented in the miRNA cargo of EVs secreted by eMSCs. The niche from which MSCs originated defined the transcriptomic signature of the cells, including the secretion of lineage-specific loaded EV to ensure proper communication and homeostasis. Identification and testing their biological functions can provide new tools for the therapeutic use of horse MSC.

MiR-542-3p Suppresses Neuroblastoma Cell Proliferation and Invasion by Downregulation of KDM1A and ZNF346

Neuroblastoma is one of the most common malignancies in infants and children. MicroRNAs (miRNAs) have been reported as significant regulators that play important roles in neuroblastoma development. This research aimed to analyze the functional mechanism of miR-542-3p in neuroblastoma. Here, we found that miR-542-3p was downregulated and KDM1A as well as ZNF346 were upregulated in neuroblastoma tissues and cells. Both overexpression of miR-542-3p and the knockdown of KDM1A suppressed cell proliferation and invasion in neuroblastomas. Moreover, miR-542-3p reduced the levels of KDM1A and ZNF346 through interaction. Both KDM1A overexpression and ZNF346 upregulation weakened the effect of miR-542-3p on neuroblastoma cells. Besides, miR-542-3p negatively regulated tumor growth in vivo. Our results suggested that miR-542-3p suppressed cell proliferation and invasion by targeting KDM1A and ZNF346 in neuroblastomas, providing a theoretical basis for the treatment of neuroblastoma.

MicroRNA dysregulation interplay with childhood abdominal tumors

Abdominal tumors (AT) in children account for approximately 17% of all pediatric solid tumor cases, and frequently exhibit embryonal histological features that differentiate them from adult cancers. Current molecular approaches have greatly improved the understanding of the distinctive pathology of each tumor type and enabled the characterization of novel tumor biomarkers. As seen in abdominal adult tumors, microRNAs (miRNAs) have been increasingly implicated in either the initiation or progression of childhood cancer. Moreover, besides predicting patient prognosis, they represent valuable diagnostic tools that may also assist the surveillance of tumor behavior and treatment response, as well as the identification of the primary metastatic sites. Thus, the present study was undertaken to compile up-to-date information regarding the role of dysregulated miRNAs in the most common histological variants of AT, including neuroblastoma, nephroblastoma, hepatoblastoma, hepatocarcinoma, and adrenal tumors. Additionally, the clinical implications of dysregulated miRNAs as potential diagnostic tools or indicators of prognosis were evaluated.

microRNA-329 suppresses epithelial-to-mesenchymal transition and lymph node metastasis in bile duct cancer by inhibiting laminin subunit beta 3

Bile duct cancer (BDC), also known as cholangiocarcinoma, is a highly desmoplastic cancer with a growth pattern characterized by periductal extension and infiltration. Studies have suggested that microRNAs (miRNAs) play an important role in BDC progression. Here we aim at investigating the effects of miR-329 on BDC development, focusing especially on epithelial-to-mesenchymal transition (EMT) in vitro and lymph node metastasis in vivo. Expression microarrays associated with BDC tissues were collected and differentially expressed genes were analyzed, followed by miRNA target prediction and verification. The role miR-329 played in BDC was examined using gain-of-function and loss-of-function methods. The expressions of miR-329, laminin subunit beta 3 (LAMB3), and EMT markers, in addition to cell proliferation, migration, and invasion were evaluated. Furthermore, nude mice models of BDC were established to observe tumor growth and metastatic lymph nodes. The LAMB3 was identified as an upregulated gene based on the GSE77984 and GSE45001 microarray analysis. LAMB3 was also predicted and confirmed to be a target gene of miR-329 by dual-luciferase reporter assay. Through further cell experiments, the EMT process was reversed, cell proliferation, invasion, and migration were suppressed, when miR-329 was upregulated. Furthermore, in vivo experiments exhibited that the overexpression of miR-329 inhibited tumor growth and the number of metastatic lymph nodes. This study provides in vivo and in vitro evidence that miR-329 inhibits BDC progression through translational repression of LAMB3. Therefore, the obtained results may aid as an experimental basis for improving prognosis of BDC.

LncRNA TP73-AS1 is a novel regulator in cervical cancer via miR-329-3p/ARF1 axis

Cervical cancer holds one of the highest morbidity and mortality in various types of cancers. It even leads to the most number of cancer-related deaths of women. A lot of research has indicated that the anomalous expression of long noncoding RNAs (lncRNAs) would induce carcinogenesis and is associated with poor prognosis of patients with cancer. However, the function and mechanism of many lncRNAs still call for further research. Tumor Protein P73 Antisense RNA 1 (TP73-AS1) is no exception. LncRNA TP73-AS1 has been found to promote cancer progressions in various cancers. It is upregulated in cervical cancer cells. The proliferation and migration ability of cervical cancer cells can also be boosted by TP73-AS1 in return. Meanwhile, miRNA-329-3p is downregulated in cervical cancer cells and could bind with both TP73-AS1 and ADP Ribosylation Factor 1 (ARF1). TP73-AS1 inhibited miR-329-3p expression while miR-329-3p inhibited ARF1 expression. More importantly, TP73-AS1 can positively regulate ARF1 expression. Based on all these experiments, TP73-AS1 regulates ARF1 expression by competitively binding with miR-329-3p, thus regulating cervical cancer progression. Further rescue assays confirmed TP73-AS1 regulates cervical cell proliferation and migration via miR-329-3p/ARF1. TP73-AS1 might serve as a novel regulator in cervical cancer.

MicroRNA-329 upregulation impairs the HMGB2/β-catenin pathway and regulates cell biological behaviors in melanoma

Melanoma is responsible for the majority of deaths caused by skin cancer. Antitumor activity of microRNA-329 (miR-329) has been seen in several human cancers. In this study, we identify whether miR-329 serves as a candidate regulator in melanoma. Melanoma-related differentially expressed genes were screened with its potential molecular mechanism predicted. Melanoma tissues and pigmented nevus tissues were collected, where the levels of miR-329 and high-mobility group box 2 (HMGB2) were determined. To characterize the regulatory role of miR-329 on HMGB2 and the β-catenin pathway in melanoma cell activities, miR-329 mimics, miR-329 inhibitors, and siRNA-HMGB2 were transfected into melanoma cells. Cell viability, migration, invasion, cell cycle, and apoptosis were assessed. miR-329 was predicted to influence melanoma by targeting HMGB2 via the β-catenin pathway. High level of HMGB2 and low miR-329 expression were observed in melanoma tissues. HMGB2 was targeted and negatively regulated by miR-329. In melanoma cells transfected with miR-329 mimics or siRNA-HMGB2, cell proliferation, migration, and invasion were impeded, yet cell cycle arrest and apoptosis were promoted, corresponding to decreased levels of β-catenin, cyclin D1, and vimentin and increased levels of GSK3β and E-cadherin. Collectively, our results show that miR-329 can suppress the melanoma progression by downregulating HMGB2 via the β-catenin pathway.

Circulating microRNAs miR-331 and miR-195 differentiate local luminal a from metastatic breast cancer

BACKGROUND

Breast cancer is the leading cause of cancer related death in women, with metastasis the principle cause of mortality. New non-invasive prognostic markers are needed for the early detection of metastasis, facilitating treatment decision optimisation. MicroRNA (miRNA) are small, non-coding RNAs regulating gene expression and involved in many cellular processes, including metastasis. As biomarkers, circulating miRNAs (in blood) hold great promise for informing diagnosis or monitoring treatment responses.

METHODS

Plasma extracted RNA from age matched local Luminal A (n = 4) or metastatic disease (n = 4) were profiled using Next Generation Sequencing. Selected differentially expressed miRNA were validated on a whole blood extracted miRNA cohort [distant metastatic disease (n = 22), local disease (n = 31), healthy controls (n = 21)]. Area Under the Curve (AUC) in Receiver Operating Characteristic (ROC) analyses was performed.

RESULTS

Of 4 miRNA targets tested (miR-181a, miR-329, miR-331, miR-195), mir-331 was significantly over-expressed in patients with metastatic disease, compared to patients with local disease (p < 0.001) or healthy controls (p < 0.001). miR-195 was significantly under-expressed in patients with metastatic disease, compared to patients with local disease (p < 0.001) or healthy controls (p = 0.043). In combination, miR-331 and miR-195 produced an AUC of 0.902, distinguishing metastatic from local breast cancer.

CONCLUSIONS

We identified and validated two circulating miRNAs differentiating local Luminal A breast cancers from metastatic breast cancers. Further investigation will reveal the molecular role of these miRNAs in metastasis, and determine if they are subtype specific. This work demonstrates the ability of circulating miRNA to identify metastatic disease, and potentially inform diagnosis or treatment effectiveness.

miR‑329‑3p regulates neural stem cell proliferation by targeting E2F1

Neural stem cells (NSCs) are a class of self‑renewing and undifferentiated progenitor cells that retain the ability to differentiate to neurons, astrocytes and oligodendrocytes. MicroRNAs (miRNAs) are small noncoding RNAs that serve crucial roles in regulating a number of cellular processes, including cell proliferation, differentiation and apoptosis. Our previous GeneChip data indicated that the expression of miR‑329‑3p was increased in neurons compared with NSCs. However, whether miRNA‑329‑3p participates in regulating NSC function remains to be elucidated. In the present study, it was identified that the expression of miR‑329‑3p was upregulated in NSCs during neuronal differentiation, whereas expression of transcription factor E2F1 (E2F1), a putative target gene of miR‑329‑3p, was downregulated. Using luciferase reporter assays, it was confirmed that miR‑329‑3p regulated E2F1 expression. As differentiation has been demonstrated to limit the proliferative capacity of NSCs, the effects of miR‑329‑3p and E2F1 modulation on NSC proliferation were examined. Forced overexpression of miR‑329‑3p or RNA‑mediated silencing of E2F1 inhibited NSC proliferation, and overexpression of miR‑329‑3p also inhibited E2F1 expression. Notably, ectopic expression of E2F1 reversed the inhibition of NSC proliferation induced by miR‑329‑3p overexpression. These results indicated that miR‑329‑3p may serve crucial roles in regulating the proliferation of NSCs, at least in part via inhibition of E2F1 expression. These data improve the understanding of the microRNA‑mRNA regulatory network that controls NSC proliferation.

miR-329 inhibits papillary thyroid cancer progression via direct targeting WNT1

Dysregulated microRNA-329 (miR-329) serves an important role in the progression of certain types of tumor. However, the exact function and mechanisms of miR-329 in papillary thyroid cancer (PTC) remain unknown. The present study investigated the function and mechanisms of miR-329 in regulating PTC cell progression. The results revealed that the expression of miR-329 was significantly downregulated in PTC tissues and cell lines compared with adjacent normal tissues and a human immortalized follicular cell line. miR-329 mimics notably decreased PTC cell proliferation, colony formation and WNT1 expression in vitro, as well as suppressing PTC tumor growth in vivo. In addition, luciferase assays determined that miR-329 was able to directly bind with the 3'untranslated region of WNT1. Furthermore, short interfering RNA-WNT1-induced downregulation of WNT1, which demonstrated similar effects to miR-329 overexpression. WNT1 overexpression rescued the tumor suppressive effects of miR-329 in PTC cells. The present study provided new insights into the role of miR-329 in PTC progression and suggests the potential application of miR-329 as a therapy for PTC.

KDM1A microenvironment, its oncogenic potential, and therapeutic significance

The lysine-specific histone demethylase 1A (KDM1A) was the first demethylase to challenge the concept of the irreversible nature of methylation marks. KDM1A, containing a flavin adenine dinucleotide (FAD)-dependent amine oxidase domain, demethylates histone 3 lysine 4 and histone 3 lysine 9 (H3K4me1/2 and H3K9me1/2). It has emerged as an epigenetic developmental regulator and was shown to be involved in carcinogenesis. The functional diversity of KDM1A originates from its complex structure and interactions with transcription factors, promoters, enhancers, oncoproteins, and tumor-associated genes (tumor suppressors and activators). In this review, we discuss the microenvironment of KDM1A in cancer progression that enables this protein to activate or repress target gene expression, thus making it an important epigenetic modifier that regulates the growth and differentiation potential of cells. A detailed analysis of the mechanisms underlying the interactions between KDM1A and the associated complexes will help to improve our understanding of epigenetic regulation, which may enable the discovery of more effective anticancer drugs.

MicroRNA-1247 inhibits cell proliferation by directly targeting ZNF346 in childhood neuroblastoma

BACKGROUND

Neuroblastoma (NB) represents the most common extracranial solid tumor in children. Accumulating evidence shows that microRNAs (miRs) play an important role in the carcinogenesis of NB. Here, we investigated the biological function of miR-1247 in NB in vitro.

METHODS/RESULTS

We found miR-1247 was downregulated in NB tissues and cells using quantitative PCR analysis. Gain- and loss-of-function studies demonstrated that miR-1247 significantly suppressed cell proliferation and induced cell cycle G0/G1 phase arrest and cell apoptosis of NB cells in vitro by using MTT, colony formation assay and Flow cytometry analysis. Luciferase assay suggested ZNF346 was the target of miR-1247 and its expression could be downregulated by miR-1247 overexpression using Western blotting. Furthermore, downregulation of ZNF346 by siRNA performed similar effects with overexpression of miR-1247 in NB cells.

CONCLUSIONS

Our findings suggested miR-1247 directly targeted to repress ZNF346 expression, thus suppressing the progression of NB, which might be a novel therapeutic target against NB.

Targeting of epigenetic regulators in neuroblastoma

Approximately 15,000 new cases of pediatric cancer are diagnosed yearly in Europe, with 8–10% corresponding to neuroblastoma, a rare disease with an incidence of 8–9 cases per million children <15 years of age. Although the survival rate for low-risk and intermediate-risk patients is excellent, half of children with high-risk, refractory, or relapsed tumors will be cured, and two-thirds of the other half will suffer major side effects and life-long disabilities. Epigenetic therapies aimed at reversing the oncogenic alterations in chromatin structure and function are an emerging alternative against aggressive tumors that are or will become resistant to conventional treatments. This approach proposes targeting epigenetic regulators, which are proteins that are involved in the creation, detection, and interpretation of epigenetic signals, such as methylation or histone post-translational modifications. In this review, we focused on the most promising epigenetic regulators for targeting and current drugs that have already reached clinical trials.

Treatments that target chromatin, the combination of DNA and proteins, are emerging as alternative ways to treat aggressive neuroblastomas, cancers of neural tissue. Altering the structure and function of chromatin is a form of “epigenetic therapy”, treatment that affects inheritable molecular signals controlling the activity of genes, rather than targeting the genes directly. Researchers in Spain led by Miguel Segura at the Vall d’Hebron Research Institute in Barcelona review progress in developing epigenetic therapies for neuroblastomas. A growing body of fundamental research and evidence from clinical trials suggest this approach could open promising new avenues to treating aggressive and drug-resistant cancers. The authors recommend an increased effort to identify and explore the activities of small molecules that could form the basis of effective epigenetic therapies for various cancers.

MicroRNA-329 inhibits cell proliferation and tumor growth while facilitates apoptosis via negative regulation of KDM1A in gastric cancer

Altered expression of microRNA (miRNA) is strongly implicated in gastric cancer (GC). Here, we demonstrated a decreased expression of miRNA-329 in GC. Then we explored the regulatory mechanisms responsible for its effect on GC cells. GC tissues and their adjacent non-tumor tissues were collected. Complete follow-up was updated. A series of inhibitors, mimics, and siRNA against KDM1A were introduced to validate regulatory mechanisms for miR-497 and KDM1A in BGC-823 cells. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot assay were employed for evaluating the expressions of miRNA-329, KDM1A, H3K4me1, and H3K4me2. Cell proliferation, cycle progression, and apoptosis were assessed by means of an MTT assay and flow cytometry. Cell colony formation was assessed. uman gastric cancer xenotransplanted into nude mice was studied. As opposed to adjacent tissues and gastritis tissues, miRNA-329 was highly expressed and KDM1A was low expressed in GC tissues. The patients with high miRNA-329 expression or low KDM1A expression had longer survival periods. The miRNA-329 mimics and siRNA against KDM1A decreased KDM1A expression and increased H3K4me1 and H3K4me2 expressions. Forced expression of miRNA-329 in gastric cancer cells significantly promotes their capacity of apoptosis but reduces proliferation, migration, and invasion. KDM1A is a direct downstream target for miRNA-329. In a nude mouse subcutaneous tumor system, in vivo tumor growth of BGC-823 was significantly inhibited after treatment of miRNA-329 mimics or siRNA against KDM1A. We conclude that miRNA-329 functions as a tumor suppressor in GC, which could be achieved via transcriptional suppression of KDM1A.

mir-329 restricts tumor growth by targeting grb2 in pancreatic cancer

Pancreatic cancer is one of the most lethal malignancies worldwide. To illustrate the pathogenic mechanism(s), we looked into the expression and function of miR-329 associated with pancreatic cancer development. It was found that miR-329 expression was downregulated in the pancreatic cancer patients who demonstrated significantly shorter overall survival than the patients having upregulated expression. Also, more advanced pT stage cases were observed in the low miR-329 expression group of patients. Interestingly, our studies uncovered that miR-329 overexpression inhibited proliferation and induced apoptosis of pancreatic cancer cells, in contrast the miR-329 inhibitor reversed this phenomenon dramatically. Additionally, overexpression of miR-329 significantly limited tumor growth in the xenograft model. In the mechanistic study, we identified GRB2 as a direct target of miR-329 in pancreatic cancer cells, and expression of GRB2 was inversely correlated with miR-329 expression in pancreatic cancer patients. Furthermore, GRB2 overexpression in cell line and xenograft model dramatically diminished miR-329 mediated anti-proliferation and apoptosis induction, indicating that GRB2/pERK pathway was mainly downregulated by miR-329 expression. In general, our study has shed light on miR-329 regulated mechanism and, miR-329/GRB2/pERK is potential to be targeted for pancreatic cancer management.

Hsa-miR-329 exerts tumor suppressor function through down-regulation of MET in non-small cell lung cancer

MicroRNAs (miRNAs) act as key regulators of multiple cancers. Hsa-miR-329 (miR-329) functions as a tumor suppressor in some malignancies. However, its role on lung cancer remains poorly understood. In this study, we investigated the role of miR-329 on the development of lung cancer. The results indicated that miR-329 was decreased in primary lung cancer tissues compared with matched adjacent normal lung tissues and very low levels were found in a non-small cell lung cancer (NSCLC) cell lines. Ectopic expression of miR-329 in lung cancer cell lines substantially repressed cell growth as evidenced by cell viability assay, colony formation assay and BrdU staining, through inhibiting cyclin D1, cyclin D2 and up-regulatiing p57(Kip2) and p21(WAF1/CIP1). In addition, miR-329 promoted NSCLC cell apoptosis, as indicated by up-regulation of key apoptosis gene cleaved caspase-3, and down-regulation of anti-apoptosis gene Bcl2. Moreover, miR-329 inhibited cellular migration and invasiveness through inhibiting matrix metalloproteinases (MMP)-7 and MMP-9. Further, oncogene MET was revealed to be a putative target of miR-329, which was inversely correlated with miR-329 expression. Furthermore, down-regulation of MET by siRNA performed similar effects to over-expression of miR-329. Collectively, our results demonstrated that miR-329 played a pivotal role in lung cancer through inhibiting cell proliferation, migration, invasion, and promoting apoptosis by targeting oncogenic MET.

MicroRNA‑329 serves a tumor suppressive role in colorectal cancer by directly targeting transforming growth factor beta‑1

Colorectal cancer (CRC) is the third most common type of diagnosed cancer and the fourth leading cause of cancer‑associated mortalities worldwide. Increasing studies have demonstrated that the deregulation of microRNAs (miRNAs or miRs) is associated with the occurrence and development of multiple types of human cancer, including CRC. miR‑329 has been identified to be downregulated in various types of cancer; however, its expression pattern, functions and mechanisms in CRC remain unclear. The present study demonstrated that miR‑329 was lowly expressed in CRC tissue samples and cell lines. Low expression of miR‑329 was correlated with tumor‑node‑metastasis stage and lymph node metastasis in patients with CRC. In vitro experiments revealed that resumption expression of miR‑329 suppressed cell proliferation and invasion in CRC. Furthermore, the results of the present study indicated that miR‑329 targets transforming growth factor‑β1 (TGF‑β1) directly in vitro. TGF‑β1 was demonstrated to be upregulated in CRC tissue samples and inversely correlated with miR‑329 expression. Upregulation of TGF‑β1 was able to partially counteract the antitumor roles of miR‑329 on CRC cell proliferation and invasion. The results of the current study revealed that miR‑329 suppresses CRC cell proliferation and invasion through targeting TGF‑β1, thus suggesting that targeting miR‑329/TGF‑β1 may provide a novel effective therapeutic approach for the treatment of patients with CRC.

A Panel of MicroRNAs as Diagnostic Biomarkers for the Identification of Prostate Cancer

Prostate cancer is the most common non-cutaneous cancer among men; yet, current diagnostic methods are insufficient, and more reliable diagnostic markers need to be developed. One answer that can bridge this gap may lie in microRNAs. These small RNA molecules impact protein expression at the translational level, regulating important cellular pathways, the dysregulation of which can exert tumorigenic effects contributing to cancer. In this study, high throughput sequencing of small RNAs extracted from blood from 28 prostate cancer patients at initial stages of diagnosis and prior to treatment was used to identify microRNAs that could be utilized as diagnostic biomarkers for prostate cancer compared to 12 healthy controls. In addition, a group of four microRNAs (miR-1468-3p, miR-146a-5p, miR-1538 and miR-197-3p) was identified as normalization standards for subsequent qRT-PCR confirmation. qRT-PCR analysis corroborated microRNA sequencing results for the seven top dysregulated microRNAs. The abundance of four microRNAs (miR-127-3p, miR-204-5p, miR-329-3p and miR-487b-3p) was upregulated in blood, whereas the levels of three microRNAs (miR-32-5p, miR-20a-5p and miR-454-3p) were downregulated. Data analysis of the receiver operating curves for these selected microRNAs exhibited a better correlation with prostate cancer than PSA (prostate-specific antigen), the current gold standard for prostate cancer detection. In summary, a panel of seven microRNAs is proposed, many of which have prostate-specific targets, which may represent a significant improvement over current testing methods.

MicroRNA-329-3p targets MAPK1 to suppress cell proliferation, migration and invasion in cervical cancer

Cervical cancer is the second most common gynecological cancer worldwide and remains as one of the leading causes of cancer-related death among women. Despite great progress in the treatment of cervical cancer, the 5-year overall survival rate for patients with this disease remains unsatisfactory. Over the past decade, an increasing number of studies indicate a central role for microRNAs in the initiation and progression of cervical cancer. microRNA‑329-3p (miR-329-3p) has been studied in many types of human cancer; however, the expression level, biological role and the underlying mechanism of miR-329-3p in cervical cancer has not yet been investigated. In the present study, we found that the expression levels of miR-329-3p were reduced in both cervical cancer tissues and cell lines. Low miR-329-3p expression was negatively correlated with histological grade, International Federation of Gynecology and Obstetrics (FIGO) stage, and lymph node metastasis of cervical cancer patients. In addition, upregulation of miR‑329-3p suppressed cell proliferation, migration and invasion of cervical cancer. Furthermore, MAPK1 was identified as a direct target gene of miR-329-3p. MAPK1 was significantly upregulated in cervical cancer tissues and was inversely correlated with miR-329-3p expression in the cervical cancer tissues. Silencing of MAPK1 by RNA interference mimicked the effects of miR-329-3p overexpression on cell proliferation, migration and invasion in cervical cancer. Moreover, rescue experiments showed that restoration of the expression of MAPK1 reversed the effects of miR‑329-3p overexpression in cervical cancer cells. Taken together, these findings suggest that miR-329-3p has a critical tumor-suppressive roles by directly targeting MAPK1 in cervical cancer, and it may be investigated as a novel therapeutic target for the treatment of patients with this disease.

The role of micro-RNA in the regulation of signal pathways in gliomas

Gliomas are invasive brain tumors with high rates of recurrence and mortality. Glioblastoma multiforme (GBM) is the most deadly form of glioma with nearly 100% rate of recurrence and unfavorable prognosis in patients. Micro-RNAs (miR) are the class of wide-spread short non-coding RNAs that inhibit translation via binding to the mRNA of target genes. The aim of the present review is to analyze recent studies and experimental results concerning aberrant expression profiles of miR, which target components of the signaling pathways Hedgehog, Notch, Wnt, EGFR, TGFb, HIF1a in glioma/glioblastoma. Particularly, the interactions of miR with targets of 2-hydroxyglutarate (the product of mutant isocytrate dehydrogenase, R132H IDH1, which is specific for the glioma pathogenesis) have been considered in the present review. Detecting specific miRNAs in tissue and serum may serve as a diagnostic and prognostic tool for glioma, as well as for predicting treatment response of an individual patient, and potentially serving as a mechanism for creating personalized treatment strategies

MiR-329 suppresses osteosarcoma development by downregulating Rab10

MiR-329 has been proved to be a tumor suppressor gene in various malignancies, however, its role in osteosarcoma remains elusive. We found that miR-329 is remarkably downregulated in osteosarcoma tissues and relates to advanced stages. MiR-329 is able to inhibit osteosarcoma cell proliferation, promote apoptosis, and induce G0/G1 cell cycle arrest. In addition, miR-329 also suppresses wound-healing and migration ability of osteosarcoma cells and inhibits tumorigenicity in vivo. Rab10 was identified as a target of miR-329 in osteosarcoma and mediates its biofunction. These findings may shed light to the understanding of tumor development in osteosarcoma.

By downregulating TIAM1 expression, microRNA-329 suppresses gastric cancer invasion and growth

Gastric cancer (GC) is one of the most common malignant tumors worldwide. Emerging evidence has shown that abnormal microRNAs (miRNAs) expression is involved in tumorigenesis. MiR-329 was previously reported to act as a tumor suppressor or oncogene in some types of cancer. However, its function in gastric cancer (GC) is unclear. Here, we found that miR-329 was down-regulated in GC compared with adjacent controls. Enforced expression of miR-329 inhibited proliferation, migration and invasion of gastric cancer cells in vitro. We identified T lymphoma invasion and metastasis 1 (TIAM1) gene as potential target of miR-329. MiR-329 levels inversely correlated with TIAM1 expression in GC. Importantly, TIAM1 rescued the miR-329-mediated inhibition of cell invasion and proliferation. Finally, reintroduction of miR-329 significantly inhibited tumor formation of GC in the xenograft mice. Our findings suggest that miR-329 is a tumor suppressor and potential therapeutic target of GC

Downregulation of miR-329 promotes cell invasion by regulating BRD4 and predicts poor prognosis in hepatocellular carcinoma

Increasing evidence indicates that abnormal microRNA (miRNA) expression is related to hepatocellular carcinoma (HCC) development. Our study aimed to elucidate the essential role of miR-329 in HCC progression. Real-time PCR was used to analyze miR-329 and bromodomain containing 4 (BRD4) expression in HCC samples (n = 135). Cell Counting Kit-8 (CCK-8) and flow cytometric analysis were used to investigate cell proliferation and apoptosis. The transwell assay was used to examine the cell invasive ability. The regulation mechanism was confirmed by luciferase reporter and western blot assays. Kaplan-Meier analysis was used to detect the function of miR-329 on the prognosis of HCC patients. miR-329 was decreased in HCC samples and was related to tumor development. Furthermore, miR-329 significantly regulated cell invasion by targeting BRD4 but had no effect on cell proliferation and apoptosis. Moreover, downregulation of miR-329 predicted poor prognosis of HCC patients. miR-329 could control cell invasion via regulating BRD4 expression and may be a prognostic marker in HCC.

Downregulation of microRNA-362-3p and microRNA-329 promotes tumor progression in human breast cancer

p130Cas regulates cancer progression by driving tyrosine receptor kinase signaling. Tight regulation of p130Cas expression is necessary for survival, apoptosis, and maintenance of cell motility in various cell types. Several studies revealed that transcriptional and post-translational control of p130Cas are important for maintenance of its expression and activity. To explore novel regulatory mechanisms of p130Cas expression, we studied the effect of microRNAs (miRs) on p130Cas expression in human breast cancer MCF7 cells. Here, we provide experimental evidence that miR-362-3p and miR-329 perform a tumor-suppressive function and their expression is downregulated in human breast cancer. miR-362-3p and miR-329 inhibited cellular proliferation, migration, and invasion, thereby suppressing tumor growth, by downregulating p130Cas. Ectopic expression of p130Cas attenuated the inhibitory effects of the two miRs on tumor progression. Relative expression levels of miR-362-3p/329 and p130Cas between normal and breast cancer correlated inversely; miR-362-3p/329 expression was decreased, whereas that of p130Cas increased in breast cancers. Furthermore, we showed that downregulation of miR-362-3p and miR-329 was caused by differential DNA methylation of miR genes. Enhanced DNA methylation (according to methylation-specific PCR) was responsible for downregulation of miR-362-3p and miR-329 in breast cancer. Taken together, these findings point to a novel role for miR-362-3p and miR-329 as tumor suppressors; the miR-362-3p/miR-329-p130Cas axis seemingly has a crucial role in breast cancer progression. Thus, modulation of miR-362-3p/miR-329 may be a novel therapeutic strategy against breast cancer.

A Systematic Review of Histone Lysine-Specific Demethylase 1 and Its Inhibitors

Histone lysine-specific demethylase 1 (LSD1) is the first discovered and reported histone demethylase by Dr. Shi Yang's group in 2004. It is classified as a member of amine oxidase superfamily, the common feature of which is using the flavin adenine dinucleotide (FAD) as its cofactor. Since it is located in cell nucleus and acts as a histone methylation eraser, LSD1 specifically removes mono- or dimethylated histone H3 lysine 4 (H3K4) and H3 lysine 9 (H3K9) through formaldehyde-generating oxidation. It has been indicated that LSD1 and its downstream targets are involved in a wide range of biological courses, including embryonic development and tumor-cell growth and metastasis. LSD1 has been reported to be overexpressed in variety of tumors. Inactivating LSD1 or downregulating its expression inhibits cancer-cell development. LSD1 targeting inhibitors may represent a new insight in anticancer drug discovery. This review summarizes recent studies about LSD1 and mainly focuses on the basic physiological function of LSD1 and its involved mechanisms in pathophysiologic conditions, as well as the development of LSD1 inhibitors as potential anticancer therapeutic agents.

KDM1 class flavin-dependent protein lysine demethylases

Flavin-dependent, lysine-specific protein demethylases (KDM1s) are a subfamily of amine oxidases that catalyze the selective posttranslational oxidative demethylation of methyllysine side chains within protein and peptide substrates. KDM1s participate in the widespread epigenetic regulation of both normal and disease state transcriptional programs. Their activities are central to various cellular functions, such as hematopoietic and neuronal differentiation, cancer proliferation and metastasis, and viral lytic replication and establishment of latency. Interestingly, KDM1s function as catalytic subunits within complexes with coregulatory molecules that modulate enzymatic activity of the demethylases and coordinate their access to specific substrates at distinct sites within the cell and chromatin. Although several classes of KDM1-selective small molecule inhibitors have been recently developed, these pan-active site inhibition strategies lack the ability to selectively discriminate between KDM1 activity in specific, and occasionally opposing, functional contexts within these complexes. Here we review the discovery of this class of demethylases, their structures, chemical mechanisms, and specificity. Additionally, we review inhibition of this class of enzymes as well as emerging interactions with coregulatory molecules that regulate demethylase activity in highly specific functional contexts of biological and potential therapeutic importance.

miR-362-5p inhibits proliferation and migration of neuroblastoma cells by targeting phosphatidylinositol 3-kinase-C2β

miR-362-5p is down-regulated in high-risk neuroblastoma and can function as a tumor suppressor. However, its role remains poorly understood. We show that miR-362-5p is down-regulated in metastatic neuroblastoma compared with primary neuroblastoma. Overexpression of miR-362-5p inhibits cell proliferation, migration and invasion of neuroblastoma cells in vitro and suppresses tumor growth of neuroblastoma in vivo. Phosphatidylinositol 3-kinase (PI3K)-C2β is a target of miR-362-5p. Knockdown of PI3K-C2β by siRNA had a similar effect to overexpression of miR-362-5p on SH-SY5Y cells. Overexpression of PI3K-C2β partially reversed tumor-suppressive effects of miR-362-5p. We suggest that miR-362-5p suppresses neuroblastoma cell growth and motility, partially by targeting PI3K-C2β.

Liposarcoma miRNA signatures identified from genome-wide miRNA expression profiling

AIMS

To identify the miRNA expression profile of liposarcoma (LPS) that could facilitate detection of LPS, and provide the basis for further investigation of molecular-targeted therapeutic drugs.

MATERIALS & METHODS

A real-time quantitative PCR assay was performed to analyze the expression of 1888 miRNAs from 25 LPS tumor tissue samples, 16 samples of adipose tissue adjacent to the tumors and 18 normal adipose tissue samples from patients with LPS.

RESULTS

Ten dysregulated miRNAs were identified that effectively distinguished LPS tissue from adipose tissue and benign lipoma tissue, and LPS tumor tissues from normal adipose tissues in LPS patients. Furthermore, the expression profiles of miRNAs could also classify the subtype of LPS.

CONCLUSION

The identified miRNAs appear to be novel biomarkers for the detection of LPS, and may contribute to an understanding of the mechanisms of LPS tumorigenesis and its development, and further elucidate the characteristics of LPS subtypes.

MicroRNA‑144 suppresses tumorigenesis of hepatocellular carcinoma by targeting AKT3

Aberrant expression of microRNAs (miRNAs) has been shown to be associated with the progression and metastasis of cancer. Dysregulation of miR‑144 has been observed in numerous types of cancer; however, the exact role of miR‑144 in hepatocellular carcinoma (HCC) remains unclear. The present study observed that miR‑144 was downregulated in HCC tissues and cell lines. Forced overexpression of miR‑144 suppressed proliferation, migration and invasion of HCC cells. AKT3 was identified as a direct target of miR‑144 in HCC, and this was confirmed by a luciferase activity assay and western blot analysis. Overexpression of AKT3 in miR‑144 transfected HCC cells effectively reversed the tumor suppressive effects of miR‑144. Furthermore, AKT3 expression levels were inversely correlated with miR‑144 expression levels in HCC tissues. In conclusion, the results of the present study suggest that miR‑144 may act as a tumor suppressor in HCC by targeting AKT3, and miR‑144 may be a potential therapeutic candidate for HCC.

MiR-152 functions as a tumor suppressor in glioblastoma stem cells by targeting Krüppel-like factor 4

Glioblastoma (GBM) is the most common central nervous system tumor and the molecular mechanism driving its development is still largely unknown, limiting the treatment of this disease. In the present study, we explored the potential role of miR-152 in glioblastoma stem cells (GSCs) as well as the possible molecular mechanisms. Our results proved that miR-152 was down-regulated in human GSCs. Restoring the expression of miR-152 dramatically reduced the cell proliferation, cell migration and invasion as well as inducing apoptosis. Mechanistic investigations defined Krüppel-like factor 4 (KLF4) as a direct and functional downstream target of miR-152, which was involved in the miR-152-mediated tumor-suppressive effects in GSCs. Meanwhile, this process was coincided with the down-regulated LGALS3 that could be bound and promoted by KLF4, leading to attenuate the activation of MEK1/2 and PI3K signal pathways. Moreover, the in vivo study showed that miR-152 over-expression and KLF4 knockdown produced the smallest tumor volume and the longest survival in nude mice. Taken together, these results elucidated the function of miR-152 in GSCs progression and suggested a promising application of it in glioma treatment.

Downregulation of tumor suppressor menin by miR-421 promotes proliferation and migration of neuroblastoma

Neuroblastoma, featured by a high rate of spontaneous remissions, is the most common extra-cranial solid tumor in infants and children. Numerous reports have demonstrated that MicroRNAs (miRNAs) play essential roles in cancer progression, including cell proliferation, apoptosis, invasion, metastasis and angiogenesis. miR-421 functions as an onco-miR in some malignancies. However, its role in neuroblastoma remains poorly understood. In the present study, we found that miR-421 was increased in neuroblastoma tissues compared with matched adjacent normal tissues. Forced overexpression of miR-421 substantially enhanced cell proliferation, cell-cycle progression, migration, and invasion of neuroblastoma cells. At the molecular level, tumor suppressor menin was found to be a target of miR-421. Furthermore, downregulation of menin by small interfering RNA oligos exhibited similar effects with overexpression of miR-421. On the other hand, overexpression of menin partially reversed the proliferative effects of miR-421 in neuroblastoma cells. Collectively, miR-421 may promote neuroblastoma cell growth and motility partially by targeting menin.

MiR-195 inhibits the growth and metastasis of NSCLC cells by targeting IGF1R

MicroRNAs (miRNAs) are small, non-coding RNAs which act as oncogenes or tumor suppressors in multiple human cancers. Accumulating evidence reveals that aberrant expression of miRNAs contributes to the development and progression of non-small cell lung cancer (NSCLC). Here, we identified miR-195 as a tumor suppressor in NSCLC cells, whose expression level was dramatically decreased in both NSCLC tissues and cell lines. Ectopic expression of miR-195 suppressed NSCLC cell proliferation and metastasis-related traits in vitro. Insulin-like growth factor 1 receptor (IGF1R) was identified as a direct target of miR-195 in NSCLC cells. Furthermore, restoration of IGF1R remarkably attenuated the tumor suppressive effects of miR-195 on NSCLC cells. Our data suggest that miR-195 may be involved in the carcinogenesis of NSCLC partially by targeting IGF1R.