Regulation of E3 ubiquitin ligase-1 (WWP1) by microRNA-452 inhibits cancer cell migration and invasion in prostate cancer

Gallium complex K6 inhibits colorectal cancer by increasing ROS levels to induce DNA damage and enhance phosphatase and tensin homolog activity

Colorectal cancer (CRC) is one of the most common malignancies worldwide. In the clinical realm, platinum-based drugs hold an important role in the chemotherapy of CRC. Nonetheless, a multitude of patients, due to tumor protein 53 (TP53) gene mutations, experience the emergence of drug resistance. This phenomenon gravely impairs the effectiveness of therapy and long-term prognosis. Gallium, a metallic element akin to iron, has been reported that has the potential to be used to develop new metal anticancer drugs. In this study, we screened and established the gallium complex K6 as a potent antitumor agent in both in vitro and in vivo. K6 exhibited superior efficacy in impeding the growth, proliferation, and viability of CRC cells carrying TP53 mutations compared to oxaliplatin. Mechanistically, K6 escalated reactive oxygen species levels and led deoxyribonucleic acid (DNA) damage. Furthermore, K6 effectively suppressed the phosphoinositide 3-kinase (PI3K)/protein kinase B (PKB)/glycogen synthase kinase 3 beta (GSK3β) pathway, leading to the degradation of its downstream effectors myelocytomatosis (c-Myc) and Krueppel-like factor 5 (KLF5). Conversely, K6 diminished the protein expression of WW domain-containing protein 1 (WWP1) while activating phosphatase and tensin homolog (PTEN) through c-Myc degradation. This dual action further demonstrated the potential of K6 as a promising therapeutic compound for TP53-mutated CRC.

Extrachromosomal circular DNA promotes prostate cancer progression through the FAM84B/CDKN1B/MYC/WWP1 axis

BACKGROUND

Extrachromosomal circular DNA (eccDNA), a kind of circular DNA that originates from chromosomes, carries complete gene information, particularly the oncogenic genes. This study aimed to examine the contributions of FAM84B induced by eccDNA to prostate cancer (PCa) development and the biomolecules involved.

METHODS

The presence of eccDNA in PCa cells and the FAM84B transcripts that eccDNA carries were verified by outward and inward PCR. The effect of inhibition of eccDNA synthesis on FAM84B expression in PCa cells was analyzed by knocking down Lig3. The impact of FAM84B on the growth and metastases of PCa cells was verified by Cell Counting Kit-8 (CCK8), EdU, transwell assays, and a xenograft mouse model. Chromatin immunoprecipitation quantitative PCR (ChIP-qPCR) and dual-luciferase reporter assays were carried out to examine the effect of FAM84B/MYC on WWP1 transcription, and a co-immunoprecipitation (Co-IP) assay was conducted to verify the modification of CDKN1B by WWP1. The function of this molecular axis in PCa was explored by rescue assays.

RESULTS

The inhibited eccDNA synthesis significantly downregulated FAM84B in PCa cells, thereby attenuating the growth and metastasis of PCa. FAM84B promoted the transcription of WWP1 by MYC by activating the expression of MYC coterminous with the 8q24.21 gene desert in a beta catenin-dependent approach. WWP1 transcription promoted by MYC facilitated the ubiquitination and degradation of CDKN1B protein and inversely attenuated the repressive effect of CDKN1B on MYC expression. Exogenous overexpression of CDKN1B blocked FAM84B-activated MYC/WWP1 expression, thereby inhibiting PCa progression.

CONCLUSIONS

FAM84B promoted by eccDNA mediates degradation of CDKN1B via MYC/WWP1, thereby accelerating PCa progression.

Molecular landscape for risk prediction and personalized therapeutics of castration-resistant prostate cancer: at a glance

Prostate cancer (PCa) is commonly occurred with high incidence in men worldwide, and many patients will be eventually suffered from the dilemma of castration-resistance with the time of disease progression. Castration-resistant PCa (CRPC) is an advanced subtype of PCa with heterogeneous carcinogenesis, resulting in poor prognosis and difficulties in therapy. Currently, disorders in androgen receptor (AR)-related signaling are widely acknowledged as the leading cause of CRPC development, and some non-AR-based strategies are also proposed for CRPC clinical analyses. The initiation of CRPC is a consequence of abnormal interaction and regulation among molecules and pathways at multi-biological levels. In this study, CRPC-associated genes, RNAs, proteins, and metabolites were manually collected and integrated by a comprehensive literature review, and they were functionally classified and compared based on the role during CRPC evolution, i.e., drivers, suppressors, and biomarkers, etc. Finally, translational perspectives for data-driven and artificial intelligence-powered CRPC systems biology analysis were discussed to highlight the significance of novel molecule-based approaches for CRPC precision medicine and holistic healthcare.

Differential analysis of histopathological and genetic markers of cancer aggressiveness, and survival difference in EBV-positive and EBV-negative prostate carcinoma

Several studies have shown an association between prostate carcinoma (PCa) and Epstein-Barr virus (EBV); however, none of the studies so far have identified the histopathological and genetic markers of cancer aggressiveness associated with EBV in PCa tissues. In this study, we used previously characterized EBV-PCR-positive (n = 39) and EBV-negative (n = 60) PCa tissues to perform an IHC-based assessment of key histopathological and molecular markers of PCa aggressiveness (EMT markers, AR expression, perineural invasion, and lymphocytic infiltration characterization). Additionally, we investigated the differential expression of key oncogenes, EMT-associated genes, and PCa-specific oncomiRs, in EBV-positive and -negative tissues, using the qPCR array. Finally, survival benefit analysis was also performed in EBV-positive and EBV-negative PCa patients. The EBV-positive PCa exhibited a higher percentage (80%) of perineural invasion (PNI) compared to EBV-negative PCa (67.3%) samples. Similarly, a higher lymphocytic infiltration was observed in EBV-LMP1-positive PCa samples. The subset characterization of T and B cell lymphocytic infiltration showed a trend of higher intratumoral and tumor stromal lymphocytic infiltration in EBV-negative tissues compared with EBV-positive tissues. The logistic regression analysis showed that EBV-positive status was associated with decreased odds (OR = 0.07; p-value < 0.019) of CD3 intratumoral lymphocytic infiltration in PCa tissues. The analysis of IHC-based expression patterns of EMT markers showed comparable expression of all EMT markers, except vimentin, which showed higher expression in EBV-positive PCa tissues compared to EBV-negative PCa tissues. Furthermore, gene expression analysis showed a statistically significant difference (p < 0.05) in the expression of CDH1, AR, CHEK-2, CDKN-1B, and CDC-20 and oncomiRs miR-126, miR-152-3p, miR-452, miR-145-3p, miR-196a, miR-183-3p, and miR-146b in EBV-positive PCa tissues compared to EBV-negative PCa tissues. Overall, the survival proportion was comparable in both groups. The presence of EBV in the PCa tissues results in an increased expression of certain oncogenes, oncomiRs, and EMT marker (vimentin) and a decrease in CD3 ITL, which may be associated with the aggressive forms of PCa.

WWP1 E3 ligase at the crossroads of health and disease

The E3 ubiquitin ligase WWP1 (WW Domain-containing E3 Ubiquitin Protein Ligase 1) is a member of the HECT (Homologous to the E6-associated protein Carboxyl Terminus) E3 ligase family. It is conserved across several species and plays crucial roles in various physiological processes, including development, cell growth and proliferation, apoptosis, and differentiation. It exerts its functions through ubiquitination or protein-protein interaction with PPXY-containing proteins. WWP1 plays a role in several human diseases, including cardiac conditions, neurodevelopmental, age-associated osteogenic disorders, infectious diseases, and cancers. In solid tumors, WWP1 plays a dual role as both an oncogene and a tumor suppressor, whereas in hematological malignancies such as AML, it is identified as a dedicated oncogene. Importantly, WWP1 inhibition using small molecule inhibitors such as Indole-3-Carbinol (I3C) and Bortezomib or siRNAs leads to significant suppression of cancer growth and healing of bone fractures, suggesting that WWP1 might serve as a potential therapeutic target for several diseases. In this review, we discuss the evolutionary perspective, structure, and functions of WWP1 and its multilevel regulation by various regulators. We also examine its emerging roles in cancer progression and its therapeutic potential. Finally, we highlight WWP1's role in normal physiology, contribution to pathological conditions, and therapeutic potential for cancer and other diseases.

Vitreous Humor Proteomic Profile in Patients With Vitreoretinal Lymphoma

Purpose

Vitreoretinal lymphoma is a high-grade malignant non-Hodgkin lymphoma with poor prognosis. The objective of this study was to elucidate the proteome profile of the vitreous in patients with vitreoretinal lymphoma (VRL), aiming to advance understanding of the pathophysiology of VRL.

Methods

Comprehensive proteomic analyses of vitreous humor using liquid chromatography with tandem mass spectrometry were performed for 10 patients with VRL, 10 control patients with idiopathic epiretinal membrane or macular hole, and 10 patients with ocular sarcoidosis. Differentially expressed proteins (DEPs) were identified by comparing VRL with controls and sarcoidosis, and functional pathway analysis was performed. Finally, vitreous concentrations of representative DEPs that were significantly upregulated in proteomics study were measured by ELISA using a separate cohort.

Results

In total, 1594 proteins were identified in the vitreous humor of VRL, control, and sarcoidosis samples. Also, 282 DEPs were detected in VRL, 249 upregulated and 33 downregulated, compared with controls. Enrichment pathway analysis showed alterations in proteasome-related pathways. Compared to controls and sarcoidosis, 14 DEPs in VRL showed significant upregulation. In the validation study, ELISA confirmed significantly higher vitreous concentrations of PSAT1, YWHAG, and 20S/26S proteasome complex in VRL compared with controls and sarcoidosis. Among the upregulated DEPs, vitreous PITHD1 and NCSTN concentrations correlated positively with vitreous IL-10 concentrations.

Conclusions

This study highlights aberrations in protein expression pattern in the vitreous of patients with VRL. The DEPs identified in this study may play pivotal roles in VRL pathogenesis, providing insights to enhance understanding of VRL pathophysiology and contribute to the development of VRL biomarkers.

Role of Mir-452-5p Overexpression in Epithelial-Mesenchymal Transition (EMT) in Early-stage Colorectal Cancer

BACKGROUND/AIM

The microRNA miR-452-5p holds a critical role in the progression of multiple tumor formations, but there is limited understanding regarding the epithelial-mesenchymal transition (EMT) progression and its underlying mechanisms in the early-stage colorectal cancer (CRC). We aimed to explore the change in miRNA expression in early-stage CRC and examine the role of these miRNAs in CRC.

MATERIALS AND METHODS

The expression levels of miR-452-5p in tissues and cells of early-stage CRC were determined by real-time quantitative polymerase chain reaction. Additionally, the biological effects of miR-452-5p on CRC were investigated by in vitro functional experiments.

RESULTS

The expression levels of miR-452-5p were found increased in early-stage CRC tissue. We found that miR-452-5p promoted CRC cell proliferation but inhibited epithelial-mesenchymal transition. Furthermore, miR-452-5p promoted cell proliferation through activation of the extracellular signal-regulated kinase pathway, and inhibited cell invasion through suppression of Slug (Snail2) expression and up-regulation of E-cadherin expression.

CONCLUSION

The expression of miR-452-5p is up-regulated in early CRC and suppresses epithelial-mesenchymal transition in CRC. These discoveries suggest that miR-452-5p has the potential to serve as a viable therapeutic target for CRC.

Unraveling the Complex Web of Mechanistic Regulation of Versatile NEDD4 Family by Non-Coding RNAs in Carcinogenesis and Metastasis: From Cell Culture Studies to Animal Models

Discoveries related to an intriguing feature of ubiquitination have prompted a detailed analysis of the ubiquitination patterns in malignant cells. How the "ubiquitinome" is reshaped during multistage carcinogenesis has garnered significant attention. Seminal studies related to the structural and functional characterization of NEDD4 (Neuronal precursor cell-expressed developmentally downregulated-4) have consolidated our understanding at a new level of maturity. Additionally, regulatory roles of non-coding RNAs have further complicated the complex interplay between non-coding RNAs and the members of NEDD4 family. These mechanisms range from the miRNA-mediated targeting of NEDD4 family members to the regulation of transcriptional factors for a broader range of non-coding RNAs. Additionally, the NEDD4-mediated degradation of different proteins is modulated by lncRNAs and circRNAs. The miRNA-mediated targeting of NEDD4 family members is also regulated by circRNAs. Tremendous advancements have been made in the identification of different substrates of NEDD4 family and in the comprehensive analysis of the molecular mechanisms by which various members of NEDD4 family catalyze the ubiquitination of substrates. In this review, we have attempted to summarize the multifunctional roles of the NEDD4 family in cancer biology, and how different non-coding RNAs modulate these NEDD4 family members in the regulation of cancer. Future molecular studies should focus on the investigation of a broader drug design space and expand the scope of accessible targets for the inhibition/prevention of metastasis.

MicroRNAs as biomarkers for early diagnosis, targeting and prognosis of prostate cancer

Globally, prostate cancer (PC) is leading cause of cancer-related mortality in men worldwide. Despite significant advances in the treatment and management of this disease, the cure rates for PC remains low, largely due to late detection. PC detection is mostly reliant on prostate-specific antigen (PSA) and digital rectal examination (DRE); however, due to the low positive predictive value of current diagnostics, there is an urgent need to identify new accurate biomarkers. Recent studies support the biological role of microRNAs (miRNAs) in the initiation and progression of PC, as well as their potential as novel biomarkers for patients' diagnosis, prognosis, and disease relapse. In the advanced stages, cancer-cell-derived small extracellular vesicles (SEVs) may constitute a significant part of circulating vesicles and cause detectable changes in the plasma vesicular miRNA profile. Recent computational model for the identification of miRNA biomarkers discussed. In addition, accumulating evidence indicates that miRNAs can be utilized to target PC cells. In this article, the current understanding of the role of microRNAs and exosomes in the pathogenesis and their significance in PC prognosis, early diagnosis, chemoresistance, and treatment are reviewed.

NEDD4 E3 ubiquitin ligases: promising biomarkers and therapeutic targets for cancer

Accumulating evidence has demonstrated that NEDD4 E3 ubiquitin ligase family plays a pivotal oncogenic role in a variety of malignancies via mediating ubiquitin dependent degradation processes. Moreover, aberrant expression of NEDD4 E3 ubiquitin ligases is often indicative of cancer progression and correlated with poor prognosis. In this review, we are going to address association of expression of NEDD4 E3 ubiquitin ligases with cancers, the signaling pathways and the molecular mechanisms by which the NEDD4 E3 ubiquitin ligases regulate oncogenesis and progression, and the therapies targeting the NEDD4 E3 ubiquitin ligases. This review provides the systematic and comprehensive summary of the latest research status of E3 ubiquitin ligases in the NEDD4 subfamily, and proposes that NEDD4 family E3 ubiquitin ligases are promising anti-cancer drug targets, aiming to provide research direction for clinical targeting of NEDD4 E3 ubiquitin ligase therapy.

MiR-15b-5p inhibits castration-resistant growth of prostate cancer cells by targeting the muscarinic cholinergic receptor CHRM3

Cholinergic receptor muscarinic 3 (CHRM3)-mediated focal adhesion kinase/YES-associated protein (YAP) signalling is essential for the growth of castration-resistant prostate cancer (CRPC) cells. Here, we evaluated the molecular mechanisms through which CHRM3 overexpression facilitates castration-resistant growth. Small RNA sequencing combined with in silico analyses revealed that CHRM3 was a putative target of miR-15b-5p. Notably, androgen deprivation suppressed miR-15b-5p expression and increased CHRM3 expression. Moreover, miR-15b-5p bound directly to CHRM3 and inhibited YAP activation induced by CHRM3 stimulation. Furthermore, miR-15b-5p abolished the growth of CRPC cells induced by CHRM3 stimulation. We conclude that the miR-15b-5p/CHRM3/YAP signalling axis promotes the castration-resistant growth of prostate cancer.

MicroRNA-452: a double-edged sword in multiple human cancers

MicroRNAs (miRNAs) are small, noncoding RNAs with important functions in development, cell differentiation, and regulation of cell cycle and apoptosis. MiRNA expression is deregulated in various pathological processes including tumorigenesis and cancer progression through various mechanisms including amplification or deletion of miRNA genes, mutations, and epigenetic silencing and defects in the miRNA biogenesis machinery. Several studies have now shown abnormal miRNA profiles and proved their involvement in the initiation and progression of cancer. Since miR-452 has diverse roles (as suppressor or oncogene) in different cellular processes including epithelial-mesenchymal transition (EMT), proliferation, migration, and invasion, in this review we highlight a brief overview of the biological function and regulatory mechanism of miR-452 and its involvement as a potential biomarker for diagnosis and treatment of various cancer types.

Targeting matrix metalloproteinases by E3 ubiquitin ligases as a way to regulate the tumor microenvironment for cancer therapy

The tumor microenvironment (TME) plays an important role in neoplastic development. Matrix metalloproteinases (MMPs) are critically involved in tumorigenesis by modulation of the TME and degradation of the extracellular matrix (ECM) in a large variety of malignancies. Evidence has revealed that dysregulated MMPs can lead to ECM damage, the promotion of cell migration and tumor metastasis. The expression and activities of MMPs can be tightly regulated by TIMPs, multiple signaling pathways and noncoding RNAs. MMPs are also finely controlled by E3 ubiquitin ligases. The current review focuses on the molecular mechanism by which MMPs are governed by E3 ubiquitin ligases in carcinogenesis. Due to the essential role of MMPs in oncogenesis, they have been considered the attractive targets for antitumor treatment. Several strategies that target MMPs have been discovered, including the use of small-molecule inhibitors, peptides, inhibitory antibodies, natural compounds with anti-MMP activity, and RNAi therapeutics. However, these molecules have multiple disadvantages, such as poor solubility, severe side-effects and low oral bioavailability. Therefore, it is necessary to discover the novel inhibitors that suppress MMPs for cancer therapy. Here, we discuss the therapeutic potential of targeting E3 ubiquitin ligases to inhibit MMPs. We hope this review will stimulate the discovery of novel therapeutics for the MMP-targeted treatment of a variety of human cancers.

Anti-cancer function of microRNA-30e is mediated by negative regulation of HELLPAR, a noncoding macroRNA, and genes involved in ubiquitination and cell cycle progression in prostate cancer

Prostate cancer (PCa) progression relies on androgen receptor (AR) function, making AR a top candidate for PCa therapy. However, development of drug resistance is common, which eventually leads to development of castration‐resistant PCa. This warrants a better understanding of the pathophysiology of PCa that facilitates the aberrant activation of key signaling pathways including AR. MicroRNAs (miRNAs) function as regulators of cancer progression as they modulate various cellular processes. Here, we demonstrate a multidimensional function of miR‐30e through the regulation of genes involved in various signaling pathways. We noted loss of miR‐30e expression in prostate tumors, which, when restored, led to cell cycle arrest, induction of apoptosis, improved drug sensitivity of PCa cells and reduced tumor progression in xenograft models. We show that experimental upregulation of miR‐30e reduces expression of mRNAs including AR, FBXO45, SRSF7 and MYBL2 and a novel long noncoding RNA (lncRNA) HELLPAR, which are involved in cell cycle, apoptosis and ubiquitination, and the effects could be rescued by inhibition of miR‐30e expression. RNA immunoprecipitation analysis confirmed direct interactions between miR‐30e and its RNA targets. We noted a newly identified reciprocal relationship between miR‐30e and HELLPAR, as inhibition of HELLPAR improved stabilization of miR‐30e. Transcriptome profiling and quantitative real‐time PCR (qRT‐PCR) validation of miR‐30e‐expressing PCa cells showed differential expression of genes involved in cell cycle progression, apoptosis and ubiquitination, which supports our in vitro study. This study demonstrates an integrated function of miR‐30e on dysregulation of miRNA/lncRNA/mRNA axes that may have diagnostic and therapeutic significance in aggressive PCa.

Genetic and Epigenetic Mechanisms Deregulate the CRL2pVHL Complex in Hepatocellular Carcinoma

Dysregulation of ubiquitin-proteasome pathway genes through copy number alteration, promoter hypomethylation, and miRNA deregulation is involved in cancer development and progression. Further characterizing alterations in these genes may uncover novel drug targets across a range of diseases in which druggable alterations are uncommon, including hepatocellular carcinoma (HCC). We analyzed 377 HCC and 59 adjacent non-malignant liver tissue samples, focusing on alterations to component genes of the widely studied CRL2^pVHL E3 ubiquitin ligase complex. mRNA upregulation of the component genes was common, and was correlated with DNA hypomethylation and copy number increase, but many tumours displayed overexpression that was not explained by either mechanism. Interestingly, we found 66 miRNAs, including 39 previously unannotated miRNAs, that were downregulated in HCC and predicted to target one or more CRL2^pVHL components. Several miRNAs, including hsa-miR-101-3p and hsa-miR-139-5p, were negatively correlated with multiple component genes, suggesting that miRNA deregulation may contribute to CRL2^pVHL overexpression. Combining miRNA and mRNA expression, DNA copy number, and methylation status into one multidimensional survival analysis, we found a significant association between greater numbers of alterations and poorer overall survival for multiple component genes. While the intricacies of CRL2^pVHL complex gene regulation require additional research, it is evident that multiple causes for the deregulation of these genes must be considered in HCC, including non-traditional mechanisms.

Abnormal expression of long non-coding RNA rhabdomyosarcoma 2-associated transcript (RMST) participates in the pathological mechanism of atherosclerosis by regulating miR-224-3p

Study shows that long non-coding RNA (lncRNA) plays a regulatory role in cardiovascular diseases, and the mechanism of rhabdomyosarcoma 2-associated transcript (RMST) in atherosclerosis (AS) is still unclear. This study aimed to evaluate the expression of RMST and its possible role in the occurrence of AS. RMST and miR-224-3p level in serum and human umbilical vein endothelial cells (HUVECs) were determined by real-time quantitative PCR (RT-qPCR). In vitro atherosclerotic cell model was achieved by treating HUVECs with ox-LDL. Receiver operating characteristic (ROC) curve assessed the diagnostic value of RMST in AS, and Pearson correlation coefficient estimated the correlation of RMST with carotid intima-media thickness (CIMT) and carotid-femoral pulse wave velocity (cfPWV). Cell counting kit-8 (CCK-8) assay and Enzyme-linked immunosorbent assay (ELISA) were performed to evaluate the effect of RMST on cell viability and inflammatory response. The luciferase analysis was used to validate the relationship between RMST and miR-224-3p. The results showed that in serum and HUVECs, RMST levels were increased, while miR-224-3p level was decreased. ROC curve suggested that RMST had clinical diagnostic value for AS. Besides, CIMT and cfPWV were positively correlated with RMST levels, respectively. In HUVECs, RMST-knockdown notably improved the cell viability and inhibited the production of inflammatory factors. Moreover, miR-224-3p was the target of RMST. In conclusion, RMST has the potential to be a diagnostic marker for AS. RMST-knockdown contributes to the enhancement of cell viability and the inhibition of inflammatory response, which may provide new insights into the conquest of AS.

WW Domain-Containing E3 Ubiquitin Protein Ligase 1: A Self-Disciplined Oncoprotein

WW domain-containing E3 ubiquitin protein ligase 1 (WWP1) is a member of C2-WW-HECT E3 ligase family. Although it may execute carcinostatic actions in some scenarios, WWP1 functions as an oncoprotein under most circumstances. Here, we comprehensively review reports on regulation of WWP1 and its roles in tumorigenesis. We summarize the WWP1-mediated ubiquitinations of diverse proteins and the signaling pathways they involved, as well as the mechanisms how they affect cancer formation and progression. According to our analysis of database, in combination with previous reports, we come to a conclusion that WWP1 expression is augmented in various cancers. Gene amplification, as well as expression regulation mediated by molecules such as non-coding RNAs, may account for the increased mRNA level of WWP1. Regulation of enzymatic activity is another important facet to upregulate WWP1-mediated ubiquitinations. Based on the published data, we conclude that WWP1 employs interactions between multiple domains to autoinhibit its polyubiquitination activity in a steady state. Association of some substrates can partially release certain autoinhibition-related domains and make WWP1 have a moderate activity of polyubiquitination. Some cancer-related mutations can fully disrupt the inhibitory interactions and make WWP1 hyperactive. High expression level or hyperactivation of WWP1 may abnormally enhance polyubiquitinations of some oncoproteins or tumor suppressors, such as ΔNp63α, PTEN and p27, and ultimately promote cell proliferation, survival, migration and invasion in tumorigenesis. Given the dysregulation and oncogenic functions of WWP1 in some cancer types, it is promising to explore some therapeutic inhibitors to tune down its activity.

METTL3-mediated mature miR-497-5p/195-5p inhibits trophoblast migration and invasion by targeting WWP1 in preeclampsia

Preeclampsia (PE) is a pregnancy-associated disorder caused by poor placentation. METTL3 as an RNA methyltransferase that plays an essential role in the regulation of the m6A modification. This work investigated the regulation of METTL3-mediated mature miR-497-5p/195-5p cluster in PE progression and identified the downstream mechanisms involved. Differentially expressed miRNAs in PE were obtained from the GSE96983 dataset. The miR-497-5p/195-5p levels in placental samples collected from 20 cases of PE patients and 18 cases of normal controls were measured by RT-qPCR. Effects of miR-497-5p/195-5p and WWP1 on trophoblast proliferation, migration, and invasion were analyzed by CCK8, EdU, wound healing and Transwell assays. Luciferase reporter and RIP experiments were conducted to verify the interaction of WWP1 with miR-497-5p/195-5p. Dot blot assay was performed to determine the m6A levels in PE. The m6A modification of pri-miR-497-5p/195-5p was determined by Me-RIP assay. Immunochemistry (IHC) and western blotting were used to examine the immunoreactivities and protein levels of METTL3 and WWP1 in placental samples from PE patients and normal controls. The miR-497-5p/195-5p levels were high in PE placenta. Functionally, overexpression of miR-497-5p/195-5p prevented trophoblast migration, invasion, and proliferation. WWP1 overexpression enhanced trophoblast migration, invasion, and proliferation. Mechanistically, WWP1 was verified to be targeted by miR-497-5p/195-5p. Moreover, METTL3 promoted the recognition of pri-miR-497-5p/195-5p by DGCR8 and enhanced the formation of mature miR-497-5p/195-5p in an m6A manner. We demonstrated that METTL3-mediated m6A modification promotes the transition of pri-miR-497-5p/195-5p to mature miRNAs, thereby upregulating miR-497-5p/195-5p to aggravate PE progression by targeting WWP1.

miRNAs and androgen deprivation therapy for prostate cancer

Androgen deprivation therapy (ADT) is mainly used for the treatment of advanced, metastatic or recurrent prostate cancer (PCa). However, patients progress to ADT resistance and castration-resistant prostate cancer (CRPC) with a poor prognosis. Reliable validated markers of ADT resistance with proven clinical utility are necessary for timely correction of the therapy as well as for improvement of patient quality of life. MiRNAs involved in the ADT response and CRPC development via multiple mechanisms may act as biomarkers for patient outcomes. Available data on miRNAs associated with the ADT response (resistance and sensitivity) are summarized and analyzed in the manuscript, including analyses using bioinformatics resources. Molecular targets of miRNAs, as well as reciprocal relations between miRNAs and their targets, were studied using different databases. Special attention was dedicated to the mechanisms of ADT resistance and CRPC development, including testosterone, PI3K-AKT, VEGF pathways and associated genes. Several different approaches can be used to search for miRNAs associated with the ADT response, each of which focuses on the associated set of miRNAs - potential markers of ADT. The intersection of these approaches and combined analysis allowed us to select the most promising miRNA markers of the ADT response. Meta-analysis of the current data indicated that the selected 5 miRNAs (miRNAs - 125b, miR-21, miR-23b, miR-27b and miR-221) and 14 genes are involved in the regulation of key processes of CRPC development and represent the most promising predictors of the ADT response, further demonstrating their potential in combination therapy for advanced PCa.

MicroRNA 452 regulates IL20RA-mediated JAK1/STAT3 pathway in inflammatory colitis and colorectal cancer

OBJECTIVE

MicroRNAs are a class of small, non-coding RNAs that play a key role in several biological and molecular processes, including tumorigenesis. We previously identified that MIR452 is upregulated in both colorectal cancer (CRC) and colitis. However, the functional mechanisms of MIR452 and its target genes in CRC and colitis are not well understood. So, we hypothesize that MIR452 can influence CRC and DSS-induced colitis model through the regulation of IL20RA and its downstream JAK-STATs signaling pathway.

METHODS

We used a luciferase reporter assay to confirm the effect of MIR452 on IL20RA expression. The protein and mRNA expression of a target gene and its associated molecules were measured by western blot, quantitative RT-PCR, and immunohistochemistry.

RESULTS

We found that the IL20RA was a direct target gene of MIR452. Overexpression of MIR452 in CRC cell lines significantly decreased IL20RA and its downstream Janus kinase 1 (JAK1), Signal transducer and activator of transcription 1 (STAT1) and STAT3. Knockdown of IL20RA in CRC cell lines by IL20RA gene silencing also decreased the expression of IL20RA, JAK1, and STAT3, but not of STAT1.

CONCLUSION

Our results suggest that MIR452 regulates STAT3 through the IL20RA-mediated JAK1 pathway, but not STAT1. Overall, MIR452 acts as tumor suppressor in human CRC and in a mouse colitis model. These findings suggest that MIR452 is a promising therapeutic target in the treatment of cancer and colitis.

Functional analysis of LAT3 in prostate cancer: Its downstream target and relationship with androgen receptor

L‐type amino acid transporter 3 (LAT3, SLC43A1) is abundantly expressed in prostate cancer (PC) and is thought to play an essential role in PC progression through the cellular uptake of essential amino acids. Here, we analyzed the expression, function, and downstream target of LAT3 in PC. LAT3 was highly expressed in PC cells expressing androgen receptor (AR), and its expression was increased by dihydrotestosterone treatment and decreased by bicalutamide treatment. In chromatin immunoprecipitation sequencing of AR, binding of AR to the SLC43A1 region was increased by dihydrotestosterone stimulation. Knockdown of LAT3 inhibited cell proliferation, migration, and invasion, and the phosphorylation of p70S6K and 4EBP‐1. Separase (ESPL1) was identified as a downstream target of LAT3 by RNA sequencing analysis. In addition, immunostaining of prostatectomy specimens was performed. In the multivariate analysis, high expression of LAT3 was an independent prognostic factor for recurrence‐free survival (hazard ratio: 3.24; P = .0018). High LAT3 expression was correlated with the pathological T stage and a high International Society of Urological Pathology grade. In summary, our results suggest that LAT3 plays an important role in the progression of PC.

The emerging role of WWP1 in cancer development and progression

Emerging evidence demonstrates that WW domain-containing E3 ubiquitin protein ligase 1 (WWP1) participates into carcinogenesis and tumor progression. In this review article, we will describe the association between dysregulated WWP1 expression and clinical features of cancer patients. Moreover, we summarize the both oncogenic and tumor suppressive functions of WWP1 in a variety of human cancers. Furthermore, we briefly describe the downstream substrates of WWP1 and its upstream factors to regulate the expression of WWP1. Notably, targeting WWP1 by its inhibitors or natural compounds is potentially useful for treating human malignancies. Finally, we provide the perspectives regarding WWP1 in cancer development and therapies. We hope this review can stimulate the research to improve our understanding of WWP1-mediated tumorigenesis and accelerate the discovery of novel therapeutic strategies via targeting WWP1 expression in cancers.

Identification of a MicroRNA-E3 Ubiquitin Ligase Regulatory Network for Hepatocyte Death in Alcohol-Associated Hepatitis

We aimed to identify a microRNA (miRNA)-E3 ubiquitin ligase regulatory network for protein substrates enriched in cell death pathways and investigate the underlying molecular mechanisms in alcohol-associated hepatitis (AH). An miRNA-E3 ubiquitin ligase regulatory network for protein substrates enriched in cell death pathways was constructed using integrated bioinformatics analysis. Differentially expressed hub miRNAs (GSE59492) and their validated miRNA target genes (GSE28619) were identified in the liver of patients with AH compared with healthy controls. Liver samples from patients with AH and healthy individuals and mice exposed to Gao-binge (acute on chronic) ethanol were used for experimental validation. Using hub miRNAs identified by weighted correlation network analysis, a miRNA-E3 ubiquitin ligase regulatory network was established based on 17 miRNAs and 7 E3 ligase genes targeted by these miRNAs that were down-regulated in AH. Among the miRNAs in this regulatory network, miR-150-5p was the only miRNA regulating the E3 ligase cytokine-inducible SH2 containing protein (CISH), the E3 ligase that regulates the largest number of substrates among all E3 ligase family members. Therefore, the CISH regulatory pathway for ubiquitinated substrates was selected for subsequent experimental validation. Consistent with the bioinformatics analysis results, expression of miR-150-5p was markedly increased, while CISH was decreased, in the livers of patients with AH and mice exposed to Gao-binge ethanol. Moreover, ubiquitination of Fas-associated protein with death domain, a predicted CISH substrate involved in the regulation of programmed cell death, was reduced in livers from mice after Gao-binge ethanol. Conclusion: Identification of the miRNA-E3 ubiquitin ligase regulatory network for protein substrates enriched in the cell death pathways provides insights into the molecular mechanisms contributing to hepatocyte death in AH.

MiR-452 Regulates C2C12 Myoblast Proliferation and Differentiation via Targeting ANGPT1

microRNAs are a kind of endogenous, non-coding, single-strand small RNA. They have been reported as an important regulatory factor in skeletal myogenesis. In this study, miR-452 was selected from RNA high-throughput sequencing data to explore its regulatory role in myogenesis. Functionally, miR-452 overexpression could promote C2C12 myoblast proliferation while inhibiting myogenic differentiation. On the contrary, inhibition of miR-452 could suppress C2C12 myoblast proliferation but accelerate myogenic differentiation. Bioinformatics analysis and dual luciferase report assays showed that Angiopoietin 1 (ANGPT1), RB1, and CACNB4 were the potential target genes of miR-452. To further confirm the target relationship between ANGPT1, RB1, and CACNB4 with miR-452, the mRNA level and protein level of these genes were detected by using RT-qPCR and Western blot, respectively. Result analysis indicated that ANGPT1 was a target gene of miR-452. In addition, knockdown of ANGPT1 could obviously promote C2C12 myoblast proliferation but block their differentiation. In summary, these results demonstrated that miR-452 promoted C2C12 myoblast proliferation and inhibited their differentiation via targeting ANGPT1.

MiR-452-5p promotes colorectal cancer progression by regulating an ERK/MAPK positive feedback loop

BACKGROUND

MiR-452-5p plays an essential role in the development of a variety of tumors, but little is known about its biological function and mechanism in colorectal cancer (CRC).

METHODS

The expression levels of miR-452-5p in CRC tissues and cells were detected by real-time quantitative PCR (qRT-PCR). Besides, the biological effects of miR-452-5p on CRC were investigated by functional experiments in vitro and in vivo. Furthermore, bioinformatics analysis, dual-luciferase reporter assay, chromatin immunecipitation assay, western blotting and recovery experiments were implemented to investigate the underlying molecular mechanism.

RESULTS

The expression level of miR-452-5p was up-regulated in CRC tissues. MiR-452-5p promoted CRC cell proliferation, cell cycle transition and chemoresistance, and inhibited cell apoptosis. Moreover, miR-452-5p directly targeted PKN2 and DUSP6 and subsequently activated the ERK/MAPK signaling pathway, and it was transcriptionally regulated by c-Jun.

CONCLUSION

To conclude, miR-452-5p expression is up-regulated in CRC, which promotes the progression of CRC by activating the miR-452-5p-PKN2/DUSP6-c-Jun positive feedback loop. These findings indicate that miR-452-5p may act as a potential therapeutic target and clinical response biomarker for CRC.

Post-Translational Modifications That Drive Prostate Cancer Progression

While a protein primary structure is determined by genetic code, its specific functional form is mostly achieved in a dynamic interplay that includes actions of many enzymes involved in post-translational modifications. This versatile repertoire is widely used by cells to direct their response to external stimuli, regulate transcription and protein localization and to keep proteostasis. Herein, post-translational modifications with evident potency to drive prostate cancer are explored. A comprehensive list of proteome-wide and single protein post-translational modifications and their involvement in phenotypic outcomes is presented. Specifically, the data on phosphorylation, glycosylation, ubiquitination, SUMOylation, acetylation, and lipidation in prostate cancer and the enzymes involved are collected. This type of knowledge is especially valuable in cases when cancer cells do not differ in the expression or mutational status of a protein, but its differential activity is regulated on the level of post-translational modifications. Since their driving roles in prostate cancer, post-translational modifications are widely studied in attempts to advance prostate cancer treatment. Current strategies that exploit the potential of post-translational modifications in prostate cancer therapy are presented.

BAP1 antagonizes WWP1-mediated transcription factor KLF5 ubiquitination and inhibits autophagy to promote melanoma progression

Accumulating evidence revealed the abnormal expression of KLF5 in human cancers while its role in melanoma remains uncharacterized. This study aimed to explore the role of KLF5 in the proliferation and metastasis of melanoma. Bioinformatics analysis was performed to detect WWP1, BAP1 and KLF5 expression in melanoma, followed by expression determination on clinical tissues from melanoma patients and cancer cells. The cancer cells were infected with lentivirus expressing KLF5 or BAP1 while PI3K, AKT and mTOR expression was detected and autophagy was observed. Treated cells were injected to mice when tumor growth was measured and autophagy-related protein was detected. Plasmids expressing WWP1 and Ub-K48 were co-transfected into treated melanoma cells while immunoprecipitation assay was performed to determine the interaction among KLF5, WWP1, and BAP1. WWP1 was poorly expressed in melanoma cells and tissues whereas KLF5 was highly expressed and was positively correlated to poor prognosis. KLF5 promoted melanoma cell malignant phenotypes as well as inhibited autophagy. Interestingly, KLF5 contributed to activation of PI3K-AKT-mTOR signaling pathway, thereby inhibiting autophagy in melanoma cells. WWP1 mediated K48-linked ubiquitination of KLF5 to promote its degradation, and BAP1 antagonized this modification and stabilized KLF5 protein expression. Besides, BAP1 promoted KLF5-mediated growth of melanoma in vivo. Taken altogether, BAP1 antagonized WWP1-mediated ubiquitination of KLF5 to inhibit autophagy and promote melanoma development.

MicroRNA-15b shuttled by bone marrow mesenchymal stem cell-derived extracellular vesicles binds to WWP1 and promotes osteogenic differentiation

Background

Osteogenic differentiation is an essential process for bone regeneration involving bone marrow mesenchymal stem cells (BMSCs). BMSC-secreted extracellular vesicles (EVs) enriched with microRNAs (miRs) have vital roles to play in mediating osteogenic differentiation. Therefore, this study aimed to explore the effect of BMSC-derived EVs loaded with miR-15b on osteogenic differentiation.

Methods

Human BMSCs (hBMSCs) were cultured and treated with plasmids overexpressing or knocking down KLF2, WWP1, and miR-15b to define the role of derived EVs in osteogenic differentiation in vitro. The expression of osteogenic differentiation-related marker was measured by Western blot analysis. The interaction among miR-15b, WWP1, and ubiquitination of KLF2 was investigated by dual-luciferase reporter, immunoprecipitation, and GST pull-down assays. Moreover, EVs from hBMSCs transfected with miR-15b inhibitor (EV-miR-15b inhibitor) were injected into ovariectomized rats to verify the effect of miR-15b on bone loss in vivo.

Results

WWP1 was downregulated, and KLF2 was upregulated during osteogenic differentiation. After co-culture with EVs, miR-15b expression was elevated and WWP1 expression was reduced in hBMSCs. Upregulation of miR-15b or KLF2 or downregulation of WWP1 or NF-κB increased ALP activity and cell mineralization, as well as osteogenic differentiation-related marker expression in hBMSCs. Mechanistically, miR-15b targeted and inhibited WWP1, thus attenuating KLF2 degradation and inhibiting NF-κB activity. Co-culture of EVs increased the bone volume and trabecular number, but decreased bone loss in ovariectomized rats, which could be reversed after treatment with EV-miR-15b inhibitor.

Conclusion

Collectively, BMSC-derived EVs loaded with miR-15b promoted osteogenic differentiation by impairing WWP1-mediated KLF2 ubiquitination and inactivating the NF-κB signaling pathway.

Graphical abstract

Discovery and validation of miR-452 as an effective biomarker for acute kidney injury in sepsis

Rationale: Sepsis is the cause of nearly half of acute kidney injury (AKI) and, unfortunately, AKI in sepsis is associated with unacceptably high rates of mortality. Early detection of AKI would guide the timely intervention and care of sepsis patients. Currently, NephroCheck, based on urinary [TIMP2]*[IGFBP7], is the only FDA approved test for early detection of AKI, which has a relatively low sensitivity for sepsis patients.

Methods:In vitro, BUMPT (Boston University mouse proximal tubular cell line) cells were treated with lipopolysaccharides (LPS). In vivo, sepsis was induced in mice by LPS injection or cecal ligation and puncture (CLP). To validate the biomarker potential of miR-452, serum and urinary samples were collected from 47 sepsis patients with AKI, 50 patients without AKI, and 10 healthy subjects.

Results: miR-452 was induced in renal tubular cells in septic AKI, and the induction was shown to be mediated by NF-κB. Notably, serum and urinary miR-452 increased early in septic mice following LPS or CLP treatment, prior to detectable renal dysfunction or tissue damage. Sepsis patients with AKI had significantly higher levels of serum and urinary miR-452 than the patients without AKI. Spearman's test demonstrated a remarkable positive correlation between urinary miR-452 and serum creatinine in sepsis patients (r=0.8269). The area under the receiver operating characteristic curve (AUC) was 0.8985 for urinary miR-452. Logistic regression analysis showed a striking 72.48-fold increase of AKI risk for every 1-fold increase of urinary miR-452 in sepsis patients. The sensitivity of urinary miR-452 for AKI detection in sepsis patients reached 87.23%, which was notably higher than the 61.54% achieved by urinary [TIMP2]*[IGFBP7], while the specificity of urinary miR-452 (78.00%) was slightly lower than that of [TIMP2]*[IGFBP7] (87.18%).

Conclusions: miR-452 is induced via NF-κB in renal tubular cells in septic AKI. The increase of miR-452, especially that in urine, may be an effective biomarker for early detection of AKI in sepsis patients.

miR-452 Reverses Abnormal Glycosylation Modification of ERα and Estrogen Resistance in TNBC (Triple-Negative Breast Cancer) Through Targeting UGT1A1

Background: The breast epithelial cells in patients with triple-negative breast cancer (TNBC) actually have specific estrogen receptor (ER) expression, and the abnormal glycosylation of UGT1A1 in TNBC cells resulted in abnormal expression and function of ERα through regulating the modification of ERα. Therefore, our study targets the role of UGT1A1 expression, then glycosylation modification of ERα (estrogen receptor α) and estrogen resistance in development of TNBC.

Methods: The differential expression of mRNA and miRNA in TNBC tissues was tested. Luciferase activity was analyzed in TNBC cells treated with miR-452. Moreover, the human mammary gland and TNBC cell lines were dealt with estrogen and miR-452 or its inhibitors, then proliferation ability was further determined. Moreover, the role of interaction between UGT1A1 and ERα in the glycosylation modification of ERα and UGT activity, and metabolism of estrogen were assessed. The effects of miR-452 on TNBC by improving abnormal glycosylation modification of ERα by targeting UGT1A1 and estrogen resistance were studied in vitro and in vivo.

Results: The expression level of UGT1A1 in TNBC tumor tissues was higher than its matched para-tumorous tissues, but the miR-452 expression was opposite. The glycosylation modification site of ERα expressed in TNBC cells was different from that of normal mammary epithelial cells. The estrogen 17β-estradiol (E2) significantly promoted mitotic entry of TNBC cells. The interaction between UGT1A1 and ERα affected the expression level of each other, as well as the UGT enzyme activity and proliferation of TNBC cells. UGT1A1 induced production of intracellular estrogens and TNBC proliferation, but it could be reversed by overexpression of ERα. Upregulation of ERα caused the downregulation of UGT1A1 and marked decrease of intracellular estrogen products, and then suppressed TNBC proliferation. Moreover, UGT1A1 was the target gene of miR-452; miR-452 antagomir restrained TNBC xenograft.

Conclusion: Our results demonstrated that estrogen was a positive factor in the proliferation of TNBC cells at onset of mitosis through accentuating the expression and enzyme activity of UGT1A1. However, miR-452 targeted to UGT1A1, then regulated glycosylation modification of ERα, estrogen metabolism, and TNBC development associated with estrogen resistance.

Long Noncoding RNA SOX2-OT Knockdown Inhibits Proliferation and Metastasis of Prostate Cancer Cells Through Modulating the miR-452-5p/HMGB3 Axis and Inactivating Wnt/β-Catenin Pathway

Background: Recent studies have proven that abnormal expression of long noncoding RNAs (lncRNAs) often contributes to growth and invasion of cancer cells. The purpose of this study was to investigate the biological function and regulatory mechanism of lncRNA SOX2 overlapping transcript (SOX2-OT) in prostate cancer (PCa) progression. Materials and Methods: The expression of SOX2-OT, microRNA-452-5p (miR-452-5p), and high mobility group box 3 (HMGB3) was detected by quantitative real-time polymerase chain reaction (qRT-PCR). Flow cytometry was performed to determine the cell cycle distribution. Western blot assay was conducted to measure the protein levels of cyclin D1, p21, p27, E-cadherin, vimentin, and N-cadherin. The interaction between miR-452-5p and SOX2-OT or HMGB3 was predicted by bioinformatics analysis and verified by dual-luciferase reporter assay and RNA immunoprecipitation assay. The mice xenograft model was established to investigate the role of SOX2-OT in vivo. Results: SOX2-OT and HMGB3 were upregulated, whereas miR-452-5p was downregulated in PCa tissues and cells. Knockdown of SOX2-OT inhibited PCa cell growth and metastasis. MiR-452-5p could directly bind to SOX2-OT and its knockdown reversed the inhibitory effects of SOX2-OT interference on growth and metastasis of PCa cells. HMGB3 was a direct target of miR-452-5p and its knockdown weakened the promotive effects of miR-452-5p silence on growth and metastasis of PCa cells. Moreover, HMGB3 expression was inversely regulated by miR-452-5p and positively modulated by SOX2-OT. Furthermore, SOX2-OT activated the Wnt/β-catenin signaling pathway through increasing HMGB3 expression. Finally, SOX2-OT knockdown hindered tumor growth in vivo by regulating miR-452-5p/HMGB3 axis. Conclusions: SOX2-OT downregulation limited PCa cell growth and metastasis by regulating miR-452-5p/HMGB3 axis and inactivating Wnt/β-catenin signaling pathway, which might offer lncRNA-directed diagnosis and therapy for PCa.

Replisome genes regulation by antitumor miR-101-5p in clear cell renal cell carcinoma

Analysis of microRNA (miRNA) regulatory networks is useful for exploring novel biomarkers and therapeutic targets in cancer cells. The Cancer Genome Atlas dataset shows that low expression of both strands of pre‐miR‐101 (miR‐101‐5p and miR‐101‐3p) significantly predicted poor prognosis in clear cell renal cell carcinoma (ccRCC). The functional significance of miR‐101‐5p in cancer cells is poorly understood. Here, we focused on miR‐101‐5p to investigate the antitumor function and its regulatory networks in ccRCC cells. Ectopic expression of mature miRNAs or siRNAs was investigated in cancer cell lines to characterize cell function, ie, proliferation, apoptosis, migration, and invasion. Genome‐wide gene expression and in silico database analyses were undertaken to predict miRNA regulatory networks. Expression of miR‐101‐5p caused cell cycle arrest and apoptosis in ccRCC cells. Downstream neighbor of son (DONSON) was directly regulated by miR‐101‐5p, and its aberrant expression was significantly associated with shorter survival in propensity score‐matched analysis (P = .0001). Knockdown of DONSON attenuated ccRCC cell aggressiveness. Several replisome genes controlled by DONSON and their expression were closely associated with ccRCC pathogenesis. The antitumor miR‐101‐5p/DONSON axis and its modulated replisome genes might be a novel diagnostic and therapeutic target for ccRCC.

The miRNAs Role in Melanoma and in Its Resistance to Therapy

Melanoma is the less common but the most malignant skin cancer. Since the survival rate of melanoma metastasis is about 10–15%, many different studies have been carried out in order to find a more effective treatment. Although the development of target-based therapies and immunotherapeutic strategies has improved chances for patient survival, melanoma treatment still remains a big challenge for oncologists. Here, we collect recent data about the emerging role of melanoma-associated microRNAs (miRNAs) currently available treatments, and their involvement in drug resistance. We also reviewed miRNAs as prognostic factors, because of their chemical stability and resistance to RNase activity, in melanoma progression. Moreover, despite miRNAs being considered small conserved regulators with the limitation of target specificity, we outline the dual role of melanoma-associated miRNAs, as oncogenic and/or tumor suppressive factors, compared to other tumors.

Involvement of Dual Strands of miR-143 (miR-143-5p and miR-143-3p) and Their Target Oncogenes in the Molecular Pathogenesis of Lung Adenocarcinoma

Our analyses of tumor-suppressive microRNAs (miRNAs) and their target oncogenes have identified novel molecular networks in lung adenocarcinoma (LUAD). Moreover, our recent studies revealed that some passenger strands of miRNAs contribute to cancer cell malignant transformation. Downregulation of both strands of the miR-143 duplex was observed in LUAD clinical specimens. Ectopic expression of these miRNAs suppressed malignant phenotypes in cancer cells, suggesting that these miRNAs have tumor-suppressive activities in LUAD cells. Here, we evaluated miR-143-5p molecular networks in LUAD using genome-wide gene expression and miRNA database analyses. Twenty-two genes were identified as potential miR-143-5p-controlled genes in LUAD cells. Interestingly, the expression of 11 genes (MCM4, RAD51, FAM111B, CLGN, KRT80, GPC1, MTL5, NETO2, FANCA, MTFR1, and TTLL12) was a prognostic factor for the patients with LUAD. Furthermore, knockdown assays using siRNAs showed that downregulation of MCM4 suppressed cell growth, migration, and invasion in LUAD cells. Aberrant expression of MCM4 was confirmed in the clinical specimens of LUAD. Thus, we showed that miR-143-5p and its target genes were involved in the molecular pathogenesis of LUAD. Identification of tumor-suppressive miRNAs and their target oncogenes may be an effective strategy for elucidation of the molecular oncogenic networks of this disease.

Cluster miRNAs and cancer: Diagnostic, prognostic and therapeutic opportunities

MiRNAs are class of noncoding RNA important for gene expression regulation in many plants, animals and viruses. MiRNA clusters contain a set of two or more miRNA encoding genes, transcribed together as polycistronic miRNAs. Currently, there are approximately 159 miRNA clusters reported in the human genome consisting of miRNAs ranging from two or more miRNA genes. A large proportion of clustered miRNAs resides in and around the fragile sites or cancer associated genomic hotspots and plays an important role in carcinogenesis. Altered expression of miRNA cluster can be pro-tumorigenic or anti-tumorigenic and can be targeted for clinical management of cancer. Over the past few years, manipulation of miRNA clusters expression is attempted for experimental purpose as well as for diagnostic, prognostic and therapeutic applications in cancer. Re-expression of miRNAs by epigenetic therapy, genome editing such as clustered regulatory interspaced short palindromic repeats (CRISPR) and miRNA mowers showed promising results in cancer therapy. In this review, we focused on the potential of miRNA clusters as a biomarker for diagnosis, prognosis, targeted therapy as well as strategies for modulating their expression in a therapeutic context. This article is categorized under: Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs RNA Processing > Processing of Small RNAs RNA in Disease and Development > RNA in Disease Regulatory RNAs/RNAi/Riboswitches > Biogenesis of Effector Small RNAs.

Small Nucleolar RNA Host Gene 12 (SNHG12) Promotes Proliferation and Invasion of Laryngeal Cancer Cells via Sponging miR-129-5p and Potentiating WW Domain-Containing E3 Ubiquitin Protein Ligase 1 (WWP1) Expression

Background

The clinical significance and biological function of long noncoding RNA SNHG12 have not been identified in laryngeal squamous cell carcinoma (LSCC).

Material/Methods

Expression levels of SNHG12, miR-129-5p, and WWP1 in LSCC tissues or cells were tested by RT-qPCR. MTT assay, flow cytometry, and Transwell assay were used to identify the progression of LSCC cells in vitro. Luciferase reporter assay was used to assess the associations among SNHG12, WWP1, and miR-129-5p.

Results

SNHG12 was significantly overexpressed in LSCC tissues compared with adjacent normal tissues. The expression level of SNHG12 was significantly associated with T classification, lymph node metastasis, and cancer stage of LSCC. High expression of SNHG12 predicted shorter disease-free survival. Suppressing SNHG12 using siRNA inhibited proliferation and invasion and promoted apoptosis in the AMC-HN-8 LSCC cell line. SNHG12, mainly located in cytoplasm of AMC-HN-8 cells, was validated by dual luciferase reporter test and RT-qPCR to directly interact with miR-129-5p. Inhibition of miR-129-5p significantly increased proliferation and invasion of AMC-HN-8 cells and ameliorated the suppressive effects of si-SNHG12. Luciferase assay showed that miR-129-5p was able to combine with the 3′UTR region of WWP1, which is generally regarded as an E3 ubiquitin protein ligase. RT-qPCR and Western blot showed that WWP1 was positively regulated by SNHG12 and negatively regulated by miR-129-5p at the mRNA level and protein level. Overexpression of WWP1 significantly increased proliferation and invasion of laryngeal cancer cells. Moreover, when SNHG12 was suppressed, rescue of WWP1 restored the proliferation and invasion abilities of AMC-HN-8 cells.

Conclusions

Our study demonstrated that SNHG12 promoted LSCC cells progression via sponging miR-129-5p and potentiating WWP1 expression.

A positive feedback loop of miR-30a-5p-WWP1-NF-κB in the regulation of glioma development

Previous studies demonstrated that miR-30a-5p promotes glioma cell growth and invasion. Furthermore, WWP1 (WW domain containing E3 ubiquitin protein ligase 1) inhibits NF-κB activation that is strongly correlated with gliomagenesis. Using the GEO database and bioinformatics analyses, we identified WWP1 was downregulated in glioma tissues and might be a putative target for miR-30a-5p. Hence, this study aims to explore the interaction among miR-30a-5p, WWP1, and NF-κB and their roles in the regulation of glioma development. We found decreased WWP and increased miR-30a-5p expression and p65 phosphorylation in glioma tissues. Furthermore, WWP1 mRNA level was negatively correlated with miR-30a-5p expression in glioma tissues. Interestingly, miR-30a-5p targeted WWP1 expression. Additionally, NF-κB p65 overexpression increased miR-30a-5p expression through direct binding of NF-κB RelA subunit to the promoter of miR-30a-5p. We also confirmed that WWP1 overexpression decreased phosphorylation of NF-κB p65. Importantly, miR-30a-5p promoted glioma cell proliferation, migration, and invasion via targeting WWP1. Furthermore, NF-κB p65 overexpression inhibited WWP1 expression and promoted glioma cell malignant behaviors via inducing miR-30a-5p transcription. Moreover, WWP1 overexpression decreased miR-30a-5p expression and inhibited glioma cell malignant behaviors via inhibiting NF-κB p65. Our further assay showed that WWP1 inhibited in vivo growth of xenograft tumors of glioma cells, accompanied with a decrease in miR-30-5p expression and phosphorylation of NF-κB p65. In conclusion, there is a "miR-30a-5p-WWP1-NF-κB" positive feedback loop, which plays an important role in regulating glioma development and might provide a potential therapeutic strategy for treating glioma.

Pirin: a potential novel therapeutic target for castration-resistant prostate cancer regulated by miR-455-5p

Androgen deprivation therapy is frequently used to treat prostate cancer (PCa), but resistance can occur, a condition known as castration‐resistant prostate cancer (CRPC). Thus, novel approaches for identification of CRPC are important for designing effective PCa treatments. Analysis of microRNA (miRNA) expression signatures by RNA sequencing showed that both passenger and guide strands of the miR‐455‐duplex (miR‐455‐5p and miR‐455‐3p, respectively) acted as antitumor miRNAs in PCa cells. The involvement of miRNA passenger strands in cancer pathogenesis is a novel concept for miRNA functionality. Based on a large patient cohort in The Cancer Genome Atlas, expression of eight miR‐455‐5p/‐3p target genes (PIR: P = 0.0137, LRP8: P = 0.0495, IGFBP3: P = 0.0172, DMBX1: P = 0.0175, CCDC64: P = 0.0446, TUBB1: P = 0.0149, KIF21B: P = 0.0336, and NFAM1: P = 0.0013) was significantly associated with poor prognosis of PCa patients. Here, we focused on PIR (pirin), a highly conserved member of the cupin superfamily. PIR expression was directly regulated by miR‐455‐5p, and PIR overexpression was detected in hormone‐sensitive prostate cancer (HSPC) surgical specimens and CRPC autopsy specimens. Loss‐of‐function assays using siRNA or an inhibitor (bisamide) showed that downregulation of PIR expression blocked cancer cell migration and invasion. Moreover, the miR‐455‐5p/PIR axis contributed to cancer cell aggressiveness. These results suggest that PIR might be a promising diagnostic marker for HSPC and CRPC. Furthermore, CRPC treatment strategies targeting PIR may be possible in the future. Identification of antitumor miRNAs, including miRNA passenger strands, may contribute to the development of new diagnostic markers and therapeutic strategies for CRPC.

The role of microRNAs in prostate cancer migration, invasion, and metastasis

Prostate cancer (PCa) is considered the most prevalent malignancy and the second major cause of cancer-related death in males from Western countries. PCa exhibits variable clinical pictures, ranging from dormant to highly metastatic cancer. PCa suffers from poor prognosis and diagnosis markers, and novel biomarkers are required to define disease stages and to design appropriate therapeutic approach by considering the possible genomic and epigenomic differences. MicroRNAs (miRNAs) comprise a class of small noncoding RNAs, which have remarkable functions in cell formation, differentiation, and cancer development and contribute in these processes through controlling the expressions of protein-coding genes by repressing translation or breaking down the messenger RNA in a sequence-specific method. miRNAs in cancer are able to reflect informative data about the current status of disease and this might benefit PCa prognosis and diagnosis since that is concerned to PCa patients and we intend to highlight it in this paper.

Sunitinib-suppressed miR-452-5p facilitates renal cancer cell invasion and metastasis through modulating SMAD4/SMAD7 signals

PURPOSE

Although microRNAs (miRNAs) were revealed as crucial modulators in tumor metastasis and target therapy, our understanding of their roles in metastatic renal cell carcinoma (mRCC) and Sunitinib treatment was limited. Here we sought to identify human miRNAs that acted as key regulators in renal cancer metastasis and Sunitinib treatment.

EXPERIMENTAL DESIGN

We focused on 2 published microarray data to select out our anchored miRNA and then explored the roles of miR-452-5p both in vitro and in vivo, which was downregulated after Sunitinib treatment while upregulated in metastasis renal cell carcinoma (RCC) tissues.

RESULTS

Here, we discovered that treating with Sunitinib, the targeted receptor tyrosine kinase inhibitor (TKI), inhibited renal cancer cell migration and invasion via attenuating the expression of miR-452-5p. The novel identified miR-452-5p was upregulated and associated with poor prognosis in RCC. Preclinical studies using multiple RCC cells and xenografts model illustrated that miR-452-5p could promote RCC cell migration and invasion in vitro and in vivo. Mechanistically, P65 could directly bind to the miR-452-5p promoter and thus transcriptionally induce miR-452-5p expression, which led to post-transcriptionally abrogate SMAD4 expression, thus inhibition of its downstream gene SMAD7.

CONCLUSION

Our study presented a road map for targeting this newly identified miR-452-5p and its SMAD4/SMAD7 signals pathway, which imparted a new potential therapeutic strategy for mRCC treatment.

Regulation of NCAPG by miR-99a-3p (passenger strand) inhibits cancer cell aggressiveness and is involved in CRPC

Effective treatments for patients with castration-resistant prostate cancer (CRPC) have not yet been established. Novel approaches for identification of putative therapeutic targets for CRPC are needed. Analyses of RNA sequencing of microRNA (miRNA) expression revealed that miR-99a-3p (passenger strand) is significantly downregulated in several types of cancers. Here, we aimed to identify novel miR-99a-3p regulatory networks and therapeutic targets for CRPC. Ectopic expression of miR-99a-3p significantly inhibited cancer cell proliferation, migration, and invasion in PCa cells. Non-SMC condensin I complex subunit G (NCAPG) was a direct target of miR-99a-3p in PCa cells. Overexpression of NCAPG was detected in CRPC clinical specimens and was significantly associated with shorter disease-free survival and advanced clinical stage. Knockdown of NCAPG inhibited cancer cell aggressiveness. The passenger strand miR-99a-3p acted as an antitumor miRNA in naïve PCa and CRPC. NCAPG was regulated by miR-99a-3p, and its overexpression was involved in CRPC pathogenesis. Involvement of passenger strand of miRNA in cancer pathogenesis is novel concept, and identification of antitumor miRNA regulatory networks in CRPC might be provided novel prognostic markers and therapeutic targets for this disease.

High expression of WWP1 predicts poor prognosis and associates with tumor progression in human colorectal cancer

WWP1 (WW domain-containing E3 ubiquitin protein ligase 1), which is frequently up-regulated in multiple human malignancies, has been demonstrated to play a critical function in cell proliferation, apoptosis and invasion. However, limited knowledge is known about the expression pattern and prognostic value of WWP1 in colorectal cancer (CRC). In this study, we firstly observed that WWP1 mRNA and protein is commonly up-regulated in CRC tissues compared with normal counterparts. Furthermore, by immunohistochemical analysis in 348 cases of CRC specimens, we demonstrated that the WWP1 protein expression is up-regulated in 58.91% (205/348) samples and detected increasing WWP1 expression is closely correlated with enhanced tumor size (P=0.022), CEA level (P=0.021), T classification (P=0.010), distant metastasis (P=0.021) and TNM stage (P=0.005). Meanwhile, Kaplan-Meier survival analysis showed CRC patients with a high WWP1 expression have a poorer overall survival (P<0.001) and disease-free survival (P=0.001) than those with a low WWP1 expression. Multivariate Cox regression analysis revealed WWP1 is the independent prognostic factors for overall survival rate of CRC patients. What's more, by CCK-8 assays and Transwell assays, we found WWP1 depletion markedly inhibited tumor proliferation and invasion in CRC cells, and cells with WWP1 overexpression had a prominently higher proliferative and invasive capacity. Most notably, we illuminated WWP1 downregulation inactivated PTEN/Akt pathway in CRC cells. Taken together, our studies revealed the prognostic value of WWP1 in CRC and support that WWP1 may act as a molecular target for CRC treatment.

The microRNA signature of patients with sunitinib failure: regulation of UHRF1 pathways by microRNA-101 in renal cell carcinoma

Molecular targeted therapy is a standard treatment for patients with advanced renal cell carcinoma (RCC). Sunitinib is one of the most common molecular-targeted drugs for metastatic RCC. Molecular mechanisms of sunitinib resistance in RCC cells is still ambiguous. The microRNA (miRNA) expression signature of patients with sunitinib failure in RCC was constructed using a polymerase chain reaction (PCR)-based array. Several miRNAs that were aberrantly expressed in RCC tissues from patients treated with sunitinib were identified in this analysis. MicroRNA-101 (miR- 101) was markedly suppressed in sunitinib treated RCC tissues. Restoration of miR-101 significantly inhibited cell migration and invasion in Caki-1 and 786-O cells. Ubiquitin-like with PHD and ring finger domains 1 (UHRF1) was directly suppressed by miR-101 in RCC cells, and overexpression of UHRF1 was confirmed in sunitinib-treated RCC tissues. The pathways of nucleotide excision repair and mismatch repair were significantly suppressed by knockdown of UHRF1. Our findings showed that antitumor miR-101- mediated UHRF1 pathways may be suppressed by sunitinib treatment.

microRNA-452 exerts growth-suppressive activity against T-cell acute lymphoblastic leukemia

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematological cancer. Although microRNA (miR)-452 serves as a tumor suppressor in multiple solid tumors, its expression and function in hematological cancers including T-ALL is largely unknown. We measured the expression of miR-452 in 38 T-ALL and 22 normal lymph node samples by real-time PCR analysis. The methylation levels in the promoter of miR-452 were determined using MethyLight assay. The effects of miR-452 overexpression on proliferation, cell cycle distribution, and tumorigenesis were explored. It was found that miR-452 expression levels were significantly lower in T-ALL specimens than in normal lymph node biopsies (P=0.0079). T-ALL specimens had a significantly higher methylation level in the promoter of miR-452 than normal lymph node tissues (P=0.0014). Consistently, miR-452 was downregulated in Jurkat and Molt-4 T-ALL cells, whose expression was restored after treatment with a demethylation agent 5-aza-2′-deoxycytidine. Ectopic expression of miR-452 inhibited the proliferation of Jurkat and Molt-4 cells and induced a G0/G1 cell cycle arrest. Overexpression of miR-452 suppressed the protein expression of BMI1 in T-ALL cells. Rescue experiments revealed that overexpression of BMI1 partially reversed the growth-suppressive effect of miR-452 on T-ALL cells. Xenograft tumor studies confirmed that overexpression of miR-452 suppressed tumor growth in nude mice and reduced the expression of BMI1. Collectively, miR-452 is epigenetically silenced and targets BMI1 to exert a growth suppressive activity in T-ALL. Restoration of miR-452 expression may represent a promising therapeutic strategy for this malignancy.

Downregulation of tumor suppressive microRNAs in vivo in dense breast tissue of postmenopausal women

Women with dense breast tissue on mammography are at higher risk of developing breast cancer but the underlying mechanisms are not well understood. De-regulation of microRNAs (miRNAs) has been associated with the onset of breast cancer. miRNAs in the extracellular space participate in the regulation of the local tissue microenvironment. Here, we recruited 39 healthy postmenopausal women attending their mammography-screen that were assessed having extreme dense or entirely fatty breasts (nondense). Microdialysis was performed in breast tissue and a reference catheter was inserted in abdominal subcutaneous fat for local sampling of extracellular compounds. Three miRNAs, associated with tumor suppression, miR-193b, miR-365a, and miR-452 were significantly down-regulated in dense breast tissue compared with nondense breast tissue. In addition, miR-452 exhibited significant negative correlations with several pro-inflammatory cytokines in vivo, which was confirmed in vitro by overexpression of miR-452 in breast cancer cells. No differences were found of miR-21, -29a, -30c, 146a, -148a, -203, or -451 in breast tissue and no miRs were different in plasma. Extracellular miRNAs may be among factors that should be included in studies of novel prevention strategies for breast cancer.

Dual Strands of Pre-miR-149 Inhibit Cancer Cell Migration and Invasion through Targeting FOXM1 in Renal Cell Carcinoma

Our recent studies revealed that dual strands of certain pre-microRNAs, e.g., pre-miR-144, pre-miR-145, and pre-miR-150, act as antitumor microRNAs (miRNAs) in several cancers. The involvement of passenger strands of miRNAs in cancer pathogenesis is a novel concept in miRNA research. The analysis of a miRNA expression signature in clear cell renal cell carcinoma (ccRCC) has revealed that the guide strand of pre-miR-149 is significantly downregulated in cancer tissues. The aims of this study were to investigate the functional significance of miR-149’s guide strand (miR-149-5p) and passenger strand (miR-149-3p), and to identify the oncogenic genes regulated by these miRNAs in ccRCC cells. The ectopic expression of these miRNAs significantly inhibited cancer cell migration and invasion in ccRCC cells. Forkhead box protein M1 (FOXM1) was directly regulated by miR-149-5p and miR-149-3p in ccRCC cells. Knockdown studies using si-FOXM1 showed that the expression of FOXM1 enhanced RCC cell aggressiveness. Interestingly, the analysis of a large number of patients in the The Cancer Genome Atlas (TCGA) database (n = 260) demonstrated that patients with high FOXM1 expression had significantly shorter survival than did those with low FOXM1 expression (p = 1.5 × 10⁻⁶). Taken together, dual strands of pre-miR-149 (miR-149-5p and miR-149-3p) acted as antitumor miRNAs through the targeting of FOXM1 in ccRCC cells.

Regulation of spindle and kinetochore-associated protein 1 by antitumor miR-10a-5p in renal cell carcinoma

Analysis of our original microRNA (miRNA) expression signature of patients with advanced renal cell carcinoma (RCC) showed that microRNA‐10a‐5p (miR‐10a‐5p) was significantly downregulated in RCC specimens. The aims of the present study were to investigate the antitumor roles of miR‐10a‐5p and the novel cancer networks regulated by this miRNA in RCC cells. Downregulation of miR‐10a‐5p was confirmed in RCC tissues and RCC tissues from patients treated with tyrosine kinase inhibitors (TKI). Ectopic expression of miR‐10a‐5p in RCC cell lines (786‐O and A498 cells) inhibited cancer cell migration and invasion. Spindle and kinetochore‐associated protein 1 (SKA1) was identified as an antitumor miR‐10a‐5p target by genome‐based approaches, and direct regulation was validated by luciferase reporter assays. Knockdown of SKA1 inhibited cancer cell migration and invasion in RCC cells. Overexpression of SKA1 was observed in RCC tissues and TKI‐treated RCC tissues. Moreover, analysis of The Cancer Genome Atlas database demonstrated that low expression of miR‐10a‐5p and high expression of SKA1 were significantly associated with overall survival in patients with RCC. These findings showed that downregulation of miR‐10a‐5p and overexpression of the SKA1 axis were highly involved in RCC pathogenesis and resistance to TKI treatment in RCC.