MicroRNA-3619-5p suppresses bladder carcinoma progression by directly targeting β-catenin and CDK2 and activating p21

Epigenetic modifications in bladder cancer: crosstalk between DNA methylation and miRNAs

Bladder cancer (BC) is a malignant tumor characterized by a high incidence of urinary system diseases. The complex pathogenesis of BC has long been a focal point in medical research. With the robust development of epigenetics, the crucial role of epigenetic modifications in the occurrence and progression of BC has been elucidated. These modifications not only affect gene expression but also impact critical biological behaviors of tumor cells, including proliferation, differentiation, apoptosis, invasion, and metastasis. Notably, DNA methylation, an important epigenetic regulatory mechanism, often manifests as global hypomethylation or hypermethylation of specific gene promoter regions in BC. Alterations in this methylation pattern can lead to increased genomic instability, which profoundly influences the expression of proto-oncogenes and tumor suppressor genes. MiRNAs, as noncoding small RNAs, participate in various biological processes of BC by regulating target genes. Consequently, this work aims to explore the interaction mechanisms between DNA methylation and miRNAs in the occurrence and development of BC. Research has demonstrated that DNA methylation not only directly influences the expression of miRNA genes but also indirectly affects the maturation and functionality of miRNAs by modulating the methylation status of miRNA promoter regions. Simultaneously, miRNAs can regulate DNA methylation levels by targeting key enzymes such as DNA methyltransferases (DNMTs), thereby establishing a complex feedback regulatory network. A deeper understanding of the crosstalk mechanisms between DNA methylation and miRNAs in BC will contribute to elucidating the complexity and dynamics of epigenetic modifications in this disease, and may provide new molecular targets and strategies for the early diagnosis, treatment, and prognostic evaluation of BC.

Non-coding RNAs in urinary bladder cancer microenvironment: Diagnostic, therapeutic, and prognostic perspective

Urinary bladder cancer (UBC) is the ninth most common cancer worldwide. Despite the reliance of UBC therapy on definite pathological grading and classifications, the clinical response among patients varies widely. The molecular basis of this type of cancer appeals to considerable research; hence, new diagnostic and therapeutic options are introduced. Convenient keywords were searched in Google Scholar, PubMed, the Egyptian Knowledge Bank (EKB), and Web of Science. The recent era of UBC research is concerned with non-coding RNAs (ncRNAs), predominantly, microRNAs (miRNAs) and long non-coding RNA (lncRNAs). In addition, snoRNAs, PIWI-interacting RNAs, mitochondrial RNAs, circular, and Schistosoma haematobium-related ncRNAs appeared to contribute to the pathogenesis of the UBC. This review underscored the recently studied ncRNAs and their importance in the pathogenesis of UBC. Besides, we introduced the prospectives regarding their diagnostic, therapeutic, and prognostic significance in UBC clinical settings. Conclusion. Oncogenic and oncosuppressor ncRNAs' definite balances and interaction within the TME of UBC are key players in the fate of the tumor. Thus, profiling ncRNA in-depth inspects the TME of the UBC for better clinical insights.

Deciphering the role of LOC124905135-related non-coding RNA cluster in human cancers: A comprehensive review

Non-coding RNAs (ncRNAs), especially microRNAs (miRNAs) and long ncRNAs (lncRNAs), are essential regulators of processes, such as the cell cycle and apoptosis. In addition to interacting with intracellular complexes and participating in diverse molecular pathways, ncRNAs can be used as clinical diagnostic biomarkers and therapeutic targets for fighting cancer. Studying ncRNA gene clusters is crucial for understanding their role in cancer and developing new treatments. LOC124905135 is a protein-coding gene encoding a collagen alpha-1(III) chain-like protein, and also acts as a gene for several ncRNAs, including miR-3619, PRR34 antisense RNA 1 (PRR34-AS1), PRR34, long intergenic ncRNA 2939 (LINC02939), LOC112268288, and MIRLET7BHG. It also serves as a host gene for three miRNAs (hsa-let7-A3, hsa-miR-4763, and hsa-let-7b). Notably, the ncRNAs derived from this particular genomic region significantly affect various cell functions, including the cell cycle and apoptosis. This cluster of ncRNAs is dysregulated in several types of cancer, exhibiting mutations, alterations in copy number, and being subject to DNA methylation and histone modification. In summary, the ncRNAs derived from the LOC124905135 cluster could be used as targets for diagnosis, therapy monitoring, and drug discovery in human cancers.

Evaluation of Efficiency of Liposome-Entrapped Iridium(III) Complexes Inhibiting Tumor Growth In Vitro and In Vivo

In this paper, three new iridium(III) complexes: [Ir(piq)2(DFIPP)]PF6 (piq = deprotonated 1-phenylisoquinoline, DFIPP = 3,4-difluoro-2-(1H-imidazo[4,5-f][1,10]phenenthrolin-2-yl)phenol, 3a), [Ir(bzq)2(DFIPP)]PF6 (bzq = deprotonated benzo[h]quinoline, 3b), and [Ir(ppy)2(DFIPP)]PF6 (ppy = deprotonated 1-phenylpyridine, 3c), were synthesized and characterized. The complexes were found to be nontoxic to tumor cells via 3-(4,5-dimethylthiazole-2-yl)-diphenyltetrazolium bromide (MTT) assay. Surprisingly, its liposome-entrapped complexes 3alip, 3blip, and 3clip on B16 cells showed strong cytotoxicity (IC50 = 13.6 ± 2.8, 9.6 ± 1.1, and 18.9 ± 2.1 μM). Entry of 3alip, 3blip, and 3clip into B16 cells decreases mitochondrial membrane potential, regulates Bcl-2 family proteins, releases cytochrome c, triggers caspase family cascade reaction, and induces apoptosis. In addition, we also found that 3alip, 3blip, and 3clip triggered ferroptosis and autophagy. In vivo studies demonstrated that 3blip inhibited melanoma growth in C57 mice with a high inhibitory rate of 83.95%, and no organic damage was found in C57 mice.

The crosstalk between non-coding RNAs and cell-cycle events: A new frontier in cancer therapy

The cell cycle comprises sequential events during which a cell duplicates its genome and divides it into two daughter cells. This process is tightly regulated to ensure that the daughter cell receives identical copied chromosomal DNA and that any errors in the DNA during replication are correctly repaired. Cyclins and their enzyme partners, cyclin-dependent kinases (CDKs), are critical regulators of G- to M-phase transitions during the cell cycle. Mitogenic signals induce the formation of the cyclin/CDK complexes, resulting in phosphorylation and activation of the CDKs. Once activated, cyclin/CDK complexes phosphorylate specific substrates that drive the cell cycle forward. The sequential activation and inactivation of cyclin-CDK complexes are tightly controlled by activating and inactivating phosphorylation events induced by cell-cycle proteins. The non-coding RNAs (ncRNAs), which do not code for proteins, regulate cell-cycle proteins at the transcriptional and translational levels, thereby controlling their expression at different cell-cycle phases. Deregulation of ncRNAs can cause abnormal expression patterns of cell-cycle-regulating proteins, resulting in abnormalities in cell-cycle regulation and cancer development. This review explores how ncRNA dysregulation can disrupt cell division balance and discusses potential therapeutic approaches targeting these ncRNAs to control cell-cycle events in cancer treatment.

Potential clinical application of microRNAs in bladder cancer

Bladder cancer (BC) is the tenth most prevalent malignancy globally, presenting significant clinical and societal challenges because of its high incidence, rapid progression, and frequent recurrence. Presently, cystoscopy and urine cytology serve as the established diagnostic methods for BC. However, their efficacy is limited by their invasive nature and low sensitivity. Therefore, the development of highly specific biomarkers and effective non-invasive detection strategies is imperative for achieving a precise and timely diagnosis of BC, as well as for facilitating an optimal tumor treatment and an improved prognosis. microRNAs (miRNAs), short noncoding RNA molecules spanning around 20-25 nucleotides, are implicated in the regulation of diverse carcinogenic pathways. Substantially altered miRNAs form robust functional regulatory networks that exert a notable influence on the tumorigenesis and progression of BC. Investigations into aberrant miRNAs derived from blood, urine, or extracellular vesicles indicate their potential roles as diagnostic biomarkers and prognostic indicators in BC, enabling miRNAs to monitor the progression and predict the recurrence of the disease. Simultaneously, the investigation centered on miRNA as a potential therapeutic agent presents a novel approach for the treatment of BC. This review comprehensively analyzes biological roles of miRNAs in tumorigenesis and progression, and systematically summarizes their potential as diagnostic and prognostic biomarkers, as well as therapeutic targets for BC. Additionally, we evaluate the progress made in laboratory techniques within this field and discuss the prospects.

Chloroprocaine antagonizes progression of breast cancer by regulating LINC00494/miR-3619-5p/MED19 axis

Breast cancer, as the most prevalent female malignancy, leads the cancer-related death in women worldwide. Local anesthetic chloroprocaine exhibits antitumor potential, but its specific functions and underlying molecular mechanisms in breast cancer remain unclear. Here, we demonstrated chloroprocaine significantly inhibited proliferation, invasion and induced apoptosis of breast cancer cells in vitro. Tumor growth and pulmonary metastasis were also suppressed in BABL/c nude mice model with chloroprocaine treatment. LINC00494 was identified as one of the most downregulated long noncoding RNAs in chloroprocaine-treated breast cancer cells by high-throughput sequencing. Futhermore, high level of LINC00494 was positively associated with poor outcome of breast cancer patients. LINC00494 acted as a "miRNAs sponge" to compete with MED19 for the biding of miR-3619-5p, led to the upregulation of MED19. LINC00494/miR-3619-5p/MED19 axis participated in chloroprocaine-mediated inhibition of proliferation, invasion and promotion of apoptosis of breast cancer cells. Consequently, our finding suggested local anesthetic chloroprocaine attenuated breast cancer aggressiveness through LINC00494-mediated signaling pathway, which detailly revealed the clinical value of chloroprocaine during breast cancer treatment.

β-catenin inhibitors in cancer therapeutics: intricacies and way forward

β-catenin is an evolutionary conserved, quintessential, multifaceted protein that plays vital roles in cellular homeostasis, embryonic development, organogenesis, stem cell maintenance, cell proliferation, migration, differentiation, apoptosis, and pathogenesis of various human diseases including cancer. β-catenin manifests both signaling and adhesive features. It acts as a pivotal player in intracellular signaling as a component of versatile WNT signaling cascade involved in embryonic development, homeostasis as well as in carcinogenesis. It is also involved in Ca2+ dependent cell adhesion via interaction with E-cadherin at the adherens junctions. Aberrant β-catenin expression and its nuclear accumulation promote the transcription of various oncogenes including c-Myc and cyclinD1, thereby contributing to tumor initiation, development, and progression. β-catenin's expression is closely regulated at various levels including its stability, sub-cellular localization, as well as transcriptional activity. Understanding the molecular mechanisms of regulation of β-catenin and its atypical expression will provide researchers not only the novel insights into the pathogenesis and progression of cancer but also will help in deciphering new therapeutic avenues. In the present review, we have summarized the dual functions of β-catenin, its role in signaling, associated mutations as well as its role in carcinogenesis and tumor progression of various cancers. Additionally, we have discussed the challenges associated with targeting β-catenin molecule with the presently available drugs and suggested the possible way forward in designing new therapeutic alternatives against this oncogene.

The relationship between microRNAs and bladder cancer: are microRNAs useful to predict bladder cancer in suspicious patients?

PURPOSE

Recent studies indicate that circulating micro RNAs (miRNAs) are novel class of non-invasive biomarkers with diagnostic and prognostic information. We evaluated the miRNA expressions in bladder cancer (BC) and their associations with disease diagnosis.

METHODS

We profiled the expressions of 379 miRNAs in the plasma samples from patients with non-muscle invasive bladder cancer (NMIBC) (n = 34) and non-malignant urological diseases as a control group (n = 32). Patients were evaluated regarding with age, miRNA expressions, by using descriptive statistics. miRNA expression in extracted RNA was quantified using the NanoString nCounter Digital Analyzer.

RESULTS

The analysis of plasma miRNA levels in the marker identification cohort indicated that plasma (miR-1260a, let-7a-3p miR-196b-5p, miR-196a-5p, miR-99a-5p, miR-615-5p, miR-4301, miR-28-3p, miR-4538, miR-1233-3p, miR-4732-5p, miR-1913, miR-1280) levels were increased in NMIBC patients compared to control subjects. There were no significant differences other parameters studied between groups.

CONCLUSIONS

The analysis of serum plasma miRNA (miR-1260a, let-7a-3p miR-196b-5p, miR-196a-5p, miR-99a-5p, miR-615-5p, miR-4301, miR-28-3p, miR-4538, miR-1233-3p, miR-4732-5p, miR-1913, miR-1280) levels could be useful plasma biomarkers for BC.

CDK2 and CDK4 targeted liensinine inhibits the growth of bladder cancer T24 cells

Bladder cancer (BCa) is a urinary tumor with limited treatment options and high mortality. Liensinine (LIEN), a natural bisbenzylisoquinoline alkaloid, has shown excellent anti-tumor effects in numerous preclinical studies. However, the anti-BCa effect of LIEN remains unclear. To the best of our knowledge, this is the first study to investigate the molecular mechanism of LIEN in the management of BCa. First, we identified the treatment-related targets of BCa; those that repeatedly occur in more than two databases, including GeneCards, Online Mendelian Inheritance in Man, DisGeNET, Therapeutic Target Database, and Drugbank. The SwissTarget database was used to screen LIEN-related targets, and those with a probability >0 were possible LIEN targets. The prospective targets of LIEN in the treatment of BCa were then determined using a Venn diagram. Second, we discovered that the PI3K/AKT pathway and senescence mediated the anti-BCa action of LIEN by using GO and KEGG enrichment analysis to explore the function of LIEN therapeutic targets. A protein-protein interaction network was created using the String website, and six algorithms of the CytoHubba plug-in were then used in Cytoscape to assess the core targets of LIEN for the therapy of BCa. The outcomes of molecular docking and dynamics simulation demonstrated that CDK2 and CDK4 proteins were the direct targets of LIEN in the management of BCa, among which CDK2 was more stable in binding to LIEN than CDK4. Finally, in vitro experiments showed that LIEN inhibited the activity and proliferation of T24 cells. The expression of p-/AKT, CDK2, and CDK4 proteins progressively decreased, while the expression and fluorescence intensity of the senescence-related protein, γH2AX, gradually increased with increasing LIEN concentration in T24 cells. Therefore, our data suggest that LIEN may promote senescence and inhibit proliferation by inhibiting the CDK2/4 and PI3K/AKT pathways in BCa.

Roles of non-coding RNAs in the metabolism and pathogenesis of bladder cancer

Bladder cancer (BC) is featured as the second most common malignancy of the urinary tract worldwide with few treatments leading to high incidence and mortality. It stayed a virtually intractable disease, and efforts to identify innovative and effective therapies are urgently needed. At present, more and more evidence shows the importance of non-coding RNA (ncRNA) for disease-related study, diagnosis, and treatment of diverse types of malignancies. Recent evidence suggests that dysregulated functions of ncRNAs are closely associated with the pathogenesis of numerous cancers including BC. The detailed mechanisms underlying the dysregulated role of ncRNAs in cancer progression are still not fully understood. This review mainly summarizes recent findings on regulatory mechanisms of the ncRNAs, long non-coding RNAs, microRNAs, and circular RNAs, in cancer progression or suppression and focuses on the predictive values of ncRNAs-related signatures in BC clinical outcomes. A deeper understanding of the ncRNA interactive network could be compelling framework for developing biomarker-guided clinical trials.

miRNAs role in bladder cancer pathogenesis and targeted therapy: Signaling pathways interplay - A review

Bladder cancer (BC) is the 11th most popular cancer in females and 4th in males. A lot of efforts have been exerted to improve BC patients' care. Besides, new approaches have been developed to enhance the efficiency of BC diagnosis, prognosis, therapeutics, and monitoring. MicroRNAs (miRNAs, miRs) are small chain nucleic acids that can regulate wide networks of cellular events. They can inhibit or degrade their target protein-encoding genes. The miRNAs are either downregulated or upregulated in BC due to epigenetic alterations or biogenesis machinery abnormalities. In BC, dysregulation of miRNAs is associated with cell cycle arrest, apoptosis, proliferation, metastasis, treatment resistance, and other activities. A variety of miRNAs have been related to tumor kind, stage, or patient survival. Besides, although new approaches for using miRNAs in the diagnosis, prognosis, and treatment of BC have been developed, it still needs further investigations. In the next words, we illustrate the recent advances in the role of miRNAs in BC aspects. They include the role of miRNAs in BC pathogenesis and therapy. Besides, the clinical applications of miRNAs in BC diagnosis, prognosis, and treatment are also discussed.

PXDNL activates the motility of urothelial bladder carcinoma cells through the Wnt/β-catenin pathway and has a prognostic value

AIMS

Although aberrant expression of peroxidasin-like (PXDNL) has been associated with carcinogenesis, its potential role in the Urothelial Carcinoma of the Bladder (UCB) remains unknown. The present study aimed to explore the role of PXDNL in UCB carcinogenesis and its potential clinical value.

MAIN METHODS

Based on The Cancer Genome Atlas (TCGA) data, bioinformatics was used to explore the potential clinical value of PXDNL. Wound healing and Transwell invasion assays were employed for the purpose of assessing the cell motility, while the Western Blotting experiments were utilized for investigating the protein expression pattern of PXDNL in UCB and investigating the Epithelial-to-Mesenchymal Transition (EMT) and Wnt/β-catenin pathways for understanding the probable mechanisms involved.

KEY FINDS

PXDNL mRNA was overexpressed in UCB tissues and indicated a poor prognosis. High PXDNL mRNA levels were also associated with advanced clinicopathological features and were regarded as independent prognostic factors for UCB. However, PXDNL showed a weak correlation with immune cell infiltration in UCB. In addition, the findings of the study verified that the existing form of the PXDNL protein was 57-kDa and it was upregulated in the UCB cell lines and tissue samples. Furthermore, silencing PXDNL inhibited, while overexpressing PXDNL promoted EMT and motility of UCB cells in vitro. Mechanistic studies showed that PXDNL activated UCB cell motility via the Wnt/β-catenin pathway.

SIGNIFICANCE

The results reveal a novel molecular target that could be further explored for developing preventive, predictive, and individualized treatment strategies for UCB.

A review on the role of cyclin dependent kinases in cancers

The Cyclin-dependent kinase (CDK) class of serine/threonine kinases has crucial roles in the regulation of cell cycle transition and is mainly involved in the pathogenesis of cancers. The expression of CDKs is controlled by a complex regulatory network comprised of genetic and epigenetic mechanisms, which are dysregulated during the progression of cancer. The abnormal activation of CDKs results in uncontrolled cancer cell proliferation and the induction of cancer stem cell characteristics. The levels of CDKs can be utilized to predict the prognosis and treatment response of cancer patients, and further understanding of the function and underlying mechanisms of CDKs in human tumors would pave the way for future cancer therapies that effectively target CDKs. Defects in the regulation of cell cycle and mutations in the genes coding cell-cycle regulatory proteins lead to unrestrained proliferation of cells leading to formation of tumors. A number of treatment modalities have been designed to combat dysregulation of cell cycle through affecting expression or activity of CDKs. However, effective application of these methods in the clinical settings requires recognition of the role of CDKs in the progression of each type of cancer, their partners, their interactions with signaling pathways and the effects of suppression of these kinases on malignant features. Thus, we designed this literature search to summarize these findings at cellular level, as well as in vivo and clinical levels.

Role of microRNAs in regulation of WNT signaling pathway in urothelial and prostate cancers

Background

Urothelial cancer (UC) and prostate cancer (PCa) are the most common cancers among men with a high ratio of mortality in advanced-stages. The higher risk of these malignancies among men can be associated with higher carcinogens exposure. Molecular pathology of UC and PCa is related to the specific mutations and aberrations in some signaling pathways. WNT signaling is a highly regulated pathway that has a pivotal role during urothelial and prostate development and homeostasis. This pathway also plays a vital role in adult stem cell niches to maintain a balance between stemness and differentiation. Deregulation of the WNT pathway is frequently correlated with tumor progression and metastasis in urothelial and prostate tumors. Therefore, regulatory factors of WNT pathways are being investigated as diagnostic or prognostic markers and novel therapeutic targets during urothelial and prostate tumorigenesis. MicroRNAs (miRNAs) have a pivotal role in WNT signaling regulation in which there are interactions between miRNAs and WNT signaling pathway during tumor progression. Since, the miRNAs are sensitive, specific, and noninvasive, they can be introduced as efficient biomarkers of tumor progression.

Main body

In present review, we have summarized all of the miRNAs that have been involved in regulation of WNT signaling pathway in urothelial and prostate cancers.

Conclusions

It was observed that miRNAs were mainly involved in regulation of WNT signaling in bladder cancer cells through targeting the WNT ligands and cytoplasmic WNT components such as WNT5A, WNT7A, CTNNB1, GSK3β, and AXIN. Whereas, miRNAs were mainly involved in regulation of WNT signaling in prostate tumor cells via targeting the cytoplasmic WNT components and WNT related transcription factors such as CTNNB1, GSK3β, AXIN, TCF7, and LEF1. MiRNAs mainly functioned as tumor suppressors in bladder and prostate cancers through the WNT signaling inhibition. This review paves the way of introducing a noninvasive diagnostic panel of WNT related miRNAs in urothelial and prostate tumors.

Wnt/β-Catenin Signalling and Its Cofactor BCL9L Have an Oncogenic Effect in Bladder Cancer Cells

Bladder cancer (BC) is characterised by a high recurrence and progression rate. However, the molecular mechanisms of BC progression remain poorly understood. BCL9L, a coactivator of β-catenin was mutated in the 5′ and 3′ untranslated regions (UTRs). We assessed the influence of UTRs mutations on BCL9L, and the role of BCL9L and Wnt/β-catenin signalling in BC cells. UTR mutations were analysed by a luciferase reporter. BCL9L protein was assessed by immunohistochemistry in BC tissues. Cell proliferation was examined by crystal violet staining and by the spheroid model. Moreover, migration and invasion were analysed in real-time using the xCelligence RTCA system. The A > T mutation at 3′ UTR of BCL9L reduces the luciferase reporter mRNA expression and activity. BCL9L is predominantly increased in dysplastic urothelial cells and muscle-invasive BC. Knockdown of BCL9L and inhibition of Wnt/β-catenin signalling significantly repress the proliferation, migration and invasion of Cal29 and T24. In addition, BCL9L knockdown reduces mRNA level of Wnt/β-catenin target genes in Cal29 but not in T24 cells. BCL9L and Wnt/β-catenin signalling play an oncogenic role in bladder cancer cells and seems to be associated with BC progression. Nevertheless, the involvement of BCL9L in Wnt/β-catenin signalling is cell-line specific.

Circ_0026134 promotes NSCLC progression by the miR-3619-5p/CHAF1B axis

BACKGROUND

Non-small cell lung cancer (NSCLC) is the leading cause of cancer death worldwide. Circular RNAs (circRNAs) have been implicated in the pathogenesis of NSCLC. In this study, we explored the molecular determinants underlying the oncogenic property of circ_0026134 in NSCLC.

METHODS

The levels of circ_0026134, miR-3619-5p and chromatin assembly factor 1 subunit B axis (CHAF1B) were assessed by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. Cell colony formation, migration, invasion and apoptosis were detected by colony formation, Transwell, and flow cytometry assays, respectively. Direct relationships among circ_0026134, miR-3619-5p and CHAF1B were verified by dual-luciferase reporter assays.

RESULTS

Our results showed that circ_0026134 was highly expressed in NSCLC tissues and cells. Reduced circ_0026134 expression or miR-3619-5p overexpression inhibited NSCLC cell colony formation, migration, invasion, glycolysis and promoted cell apoptosis in vitro. Moreover, circ_0026134 directly targeted miR-3619-5p, and circ_0026134 regulated CHAF1B expression through miR-3619-5p. CHAF1B was a downstream effector of circ_0026134 in affecting NSCLC cell functional behaviors in vitro. Additionally, circ_0026134 silencing weakened tumor growth in vivo.

CONCLUSIONS

Our study identified a novel regulatory mechanism, the circ_0026134/miR-3619-5p/CHAF1B axis, for the oncogenic role of circ_0026134 in NSCLC, highlighting circ_00261345 inhibition as a potential therapeutic method against NSCLC.

Role of hsa_circ_0066966 in proliferation and migration of hepatitis B virus-related liver cancer cells

A large proportion of liver cancer cases is caused by hepatitis B virus (HBV) infection. In recent years, an increasing number of reports have indicated that circular RNAs (circRNAs) exert regulatory effects in cancer development, whereas the role of circRNAs in HBV-positive liver cancer requires further investigation. In the present study, abnormally expressed circRNAs were identified in HBV-positive liver cancer cells through microarray analysis. A total of 1,493 differentially expressed circRNAs [absolute fold-change (FC) ≥2] in HBV-positive liver cancer cells were detected, of which 171 were upregulated and 1,322 were downregulated. Subsequently, Gene Ontology enrichment analysis indicated that the genes of dysregulated circRNAs were mainly involved in regulating Sertoli cell differentiation and development, as well as telomeric DNA binding. Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that most of these genes were enriched in cancer-related signaling pathways, including the MAPK and Hippo signaling pathways. Next, the expression levels of the top-10 dysregulated circRNAs were verified in HBV-positive liver cancer cells through reverse transcription-quantitative PCR. Among them, hsa_circ_0066966 had the highest absolute Log₂FC value and was abnormally increased in HBV-positive liver cancer cells. Functional experiments further verified that knockdown of hsa_circ_0066966 had a significant inhibitory effect on the proliferation and migration of HBV-positive liver cancer cells. By contrast, overexpression of hsa_circ_0066966 in HBV-negative liver cancer cells resulted in the opposite effect. In conclusion, in the present study, comprehensive circRNA profiling in HBV-positive liver cancer cells indicated that hsa_circ_0066966 may regulate the progression of HBV-positive liver cancer.

Exosome circCMTM3 promotes angiogenesis and tumorigenesis of hepatocellular carcinoma through miR-3619-5p/SOX9

AIM

As one of the most common and lethal carcinomas, hepatocellular carcinoma (HCC) is a global health concern and affects millions of people worldwide. Current treatments for HCC are very limited due to its unclear pathogenesis. Here, we aim to further investigate the role of circCMTM3/microRNA (miR)-3619-5p in HCC.

METHODS

Human blood samples were collected from HCC patients and healthy people. Quantitative reverse transcription-polymerase chain reaction and western blot analysis were undertaken to measure levels of circCMTM3, miR-3619-5p, SOX9, and exosome markers. The MTT, colony formation, and Transwell assays were used to examine the viability, migration, and invasion of human umbilical vein endothelial cells (HUVECs), respectively. Tube formation assay was used to assess angiogenesis. Dual luciferase assay was used to validate circCMTM3/miR-3619-5p and miR-3619-5p/SOX9 interactions. A nude mouse xenograft model was used to test the role of circCMTM3 in HCC in vivo.

RESULTS

Levels of circCMTM3 in exosomes from HCC patients and cells were elevated. Knockdown of circCMTM3 greatly decreased viability, migration, and invasion of HUVECs, as well as angiogenesis. CircCMTM3 acted as a miR-3619-5p sponge and miR-3619-5p inhibitor reversed the effects of si-circCMTM3 on angiogenesis. MiR-3619-5p directly targeted SOX9 and modulated angiogenesis through SOX9. Furthermore, knockdown of circCMTM3 suppressed angiogenesis and HCC tumor growth in vivo.

CONCLUSION

The exosome circCMTM3/miR-3619-5p/SOX9 axis from HCC cells promotes angiogenesis and thus contributes to HCC tumorigenesis.

Bladder Cancer-related microRNAs With In Vivo Efficacy in Preclinical Models

Progressive and metastatic bladder cancer remain difficult to treat. In this review, we critique seven up-regulated and 25 down-regulated microRNAs in order to identify new therapeutic entities and corresponding targets. These microRNAs were selected with respect to their efficacy in bladder cancer-related preclinical in vivo models. MicroRNAs and related targets interfering with chemoresistance, cell-cycle, signaling, apoptosis, autophagy, transcription factor modulation, epigenetic modification and metabolism are described. In addition, we highlight microRNAs targeting transmembrane receptors and secreted factors. We discuss druggability issues for the identified targets.

Cryptotanshinone, a novel PDK 4 inhibitor, suppresses bladder cancer cell invasiveness via the mTOR/β‑catenin/N‑cadherin axis

The phosphorylation of pyruvate dehydrogenase (PDH) by pyruvate dehydrogenase kinase (PDK) 4 inhibits its ability to induce a glycolytic shift. PDK4 expression is upregulated in various types of human cancer. Because PDK4 regulation is critical for metabolic changes in cancer cells, it is an attractive target for cancer therapy given its ability to shift glucose metabolism. It was previously shown that a novel PDK4 inhibitor, cryptotanshinone (CPT), suppressed the three‑dimensional (3D)‑spheroid formation of pancreatic and colorectal cancer cells. In the present study, the effects of CPT on the invasiveness of bladder cancer cells were investigated. CPT significantly suppressed the invasiveness and 3D‑spheroid formation of T24 and J82 bladder cancer cells. CPT also suppressed the phosphorylation of PDH and β‑catenin, as well as the expression of N‑cadherin, which are all critical for inducing epithelial‑mesenchymal transition (EMT). The knockdown of β‑catenin or PDK4 using specific small interfering RNAs suppressed N‑cadherin expression and invasiveness in T24 cells. An mTOR inhibitor also suppressed the phosphorylation of β‑catenin and N‑cadherin expression. Furthermore, CPT injection significantly suppressed pancreatic tumor growth and peritoneal dissemination of highly metastatic SUIT‑2 pancreatic cancer cells in a mouse orthotopic pancreatic cancer model, without evident toxicity. Moreover, immunohistochemistry analyses demonstrated decreased β‑catenin expression in CPT‑treated pancreatic tumors compared with control tumors. Taken together, these results indicate that CPT reduced the invasiveness and metastasis of bladder cancer cells by suppressing EMT via the mTOR/β‑catenin/N‑cadherin pathway.

Circular RNA profiling reveals a potential role of hsa_circ_IPCEF1 in papillary thyroid carcinoma

Circular RNAs (circRNAs) are a novel type of non‑coding RNAs that are expressed across species and are implicated in cellular biological processes, displaying dysregulated expression in various tumorigeneses. Therefore, circRNA deregulation could be a crucial event in thyroid carcinoma. The present study identified circRNA signatures in several patients with papillary thyroid carcinoma (PTC) to complement the understanding of PTC pathogenesis. Using microarray technology, the circRNA profiles in three pairs of PTC tumors and matching adjacent normal tissues were screened. Differentially expressed circRNAs were further validated by reverse transcription‑quantitative PCR in whole blood from 57 pairs of subjects. Bioinformatics data analyses including miRNA response element prediction, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway, competing endogenous RNA and KEGG Orthology‑Based Annotation System analyses were performed to predict circRNA associations with cancer‑related putative downstream miRNAs and target genes. Receiver operating characteristic curves and the area under the curve (AUC) values were acquired to assess the performance of validated circRNAs in predicting potential associations with PTC. In total, 158 dysregulated circRNAs were identified in PTC tumors relative to adjacent normal tissues. Notably, one downregulated circRNA (hsa_circ_IPCEF1) showed the preferable predictive power (AUC=0.8010, P<0.0001) and interactions with four cancer‑related genes (CASR, CDC25B, NFκB1 and SHOC2). From these analyses, one PTC‑related miRNA (hsa‑miR‑3619‑5p) was identified as a potential target for hsa_circ_IPCEF1 sponging, indicating the hsa_circ_IPCEF1/hsa‑miR‑3619‑5p axis in pathogenesis.

Long noncoding HOXA11-AS knockdown suppresses the progression of non-small cell lung cancer by regulating miR-3619-5p/SALL4 axis

Accumulating evidence suggested that many long noncoding RNAs (lncRNAs) were widely involved in the development and progression of non-small cell lung cancer (NSCLC). However, the roles of lncRNA homeobox A11 antisense (HOXA11-AS) and its underlying mechanism in NSCLC remains largely unknown. The expression levels of HOXA11-AS, miR-3619-5p and sal-like protein 4 (SALL4) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Western blot analysis was used to measure the protein levels of hexokinase II (HK2) and SALL4. Cell proliferation, apoptosis, migration and invasion were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, flow cytometry and transwell assay, respectively. The glucose consumption and lactate production were measured using glucose assay kit and lactate assay kit, respectively. The potential binding sites between miR-3619-5p and HOXA11-AS or SALL4 were predicted by online software and verified by luciferase report assay. A xenograft tumor model was established to confirm the function of HOXA11-AS in NSCLC in vivo. HOXA11-AS and SALL4 were upregulated while miR-3619-5p was downregulated in NSCLC tissues and cells. HOXA11-AS knockdown suppressed cell proliferation, migration, invasion, and glycolysis but promoted apoptosis in NSCLC cells. Moreover, miR-3619-5p could directly bind to HOXA11-AS and its inhibition attenuated the inhibitory effect of HOXA11-AS knockdown on progression of NSCLC cells. Furthermore, SALL4 was a direct target of miR-3619-5p and its overexpression reversed the anti-tumor role of miR-3619-5p in NSCLC cells. Besides, HOXA11-AS modulated SALL4 expression via sponging miR-3619-5p. Additionally, silencing HOXA11-AS inhibited tumor growth though upregulating miR-3619-5p and downregulating SALL4. Collectively, HOXA11-AS knockdown inhibited the progression of NSCLC by regulating miR-3619-5p/SALL4 axis, which might offer a novel avenue for interpreting the mechanism of NSCLC development.

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

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

Wnt signalling pathway in bladder cancer

Bladder cancer (BC) is one of the most common tumours of the urinary system and is also known as a highly malignant tumour. In addition to conventional diagnosis and treatment methods, recent research has focused on studying the molecular mechanisms related to BC, in the hope that new, less toxic and effective targeted anticancer drugs and new diagnostic markers can be discovered. It is known that the Wingless (Wnt) signalling pathway and its related genes, proteins and other substances are involved in multiple biological processes of various tumours. Clarifying the contribution of the Wnt signalling pathway in bladder tumours will help establish early diagnosis indicators, develop new therapeutic drugs and evaluate the prognosis for BC. This review aims to summarise previous studies related to BC and the Wnt signalling pathway, with a focus on exploring the participating substances and their mechanisms in the regulation of the Wnt signalling pathway to better determine how to promote new chemotherapeutic drugs, potential therapeutic targets and diagnostic biomarkers.

MicroRNAs and target molecules in bladder cancer

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

LncRNA NEAT1 Knockdown Inhibits Retinoblastoma Progression by miR-3619-5p/LASP1 Axis

Retinoblastoma (RB) is the most common intraocular tumor in childhood. Long non-coding RNA (lncRNA) nuclear paraspeckle assembly transcript 1 (NTAT1) has been reported to be related to RB progression. This study aims to study the molecular mechanism of NEAT1 in regulating cell cycle, proliferation, apoptosis, migration, and invasion in RB. The expression levels of NEAT1 and miR-3619-5p were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The protein expression of LIM and SH3 domain protein 1 (LASP1) was measured by western blot. The proliferation of RB cells was analyzed by cell counting kit-8 (CCK-8) and cell colony formation assays. Cell migration and invasion were evaluated by transwell assay. Cell cycle and apoptosis were assessed by flow cytometry analysis. The association between miR-3619-5p and NEAT1 or LASP1 was predicted by starBase 3.0 database and identified by dual-luciferase reporter assay. The effects of NEAT1 knockdown on the tumor growth in vivo were detected by in vivo tumor formation assay. NEAT1 expression was dramatically up-regulated, and miR-3619-5p expression was obviously downregulated in RB tissues and cells compared with control groups. The protein level of LASP1 was obviously increased in RB tissues or cells relative to paracancerous normal tissues or cells, respectively. Functionally, NEAT1 silencing inhibited RB cell migration, invasion, and proliferation, whereas induced cell apoptosis and cell cycle arrest in RB; this phenomenon was partially abolished by miR-3619-5p inhibitor. Mechanistically, NEAT1 acted as a sponge of miR-3619-5p, and miR-3619-5p was associated with LASP1. In addition, NEAT1 knockdown decreased the volume and weight of RB tumor in vivo. Together, NEAT1 silencing repressed cell migration, invasion, and proliferation, whereas induced cell apoptosis and cycle arrest by sponging miR-3619-5p to inhibit LASP1 expression in RB cells. This study may provide a theoretical basis for RB therapy.

Knockdown of LINC00665 inhibits proliferation and invasion of breast cancer via competitive binding of miR-3619-5p and inhibition of catenin beta 1

Background

Long intergenic non-protein coding RNA00665 (LINC00665) plays a crucial tumorigenic role in many cancers, such as gastric cancer and lung adenocarcinoma. However, its role and mechanism of action in the progression of breast cancer (BC) are unknown.

Methods

LINC00665 expression levels were determined using quantitative polymerase chain reaction analysis with BC tissues and cell lines. BC cell proliferation was tested by performing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays, whereas BC cell migration and invasion capabilities were analyzed by performing transwell migration assays. Percentages of apoptotic cells were measured by flow cytometry. Interactions between LINC00665 and miR-3169-5p were examined by performing luciferase reporter assays, and the expression levels of proteins, such as β-catenin, were examined by western blot analysis.

Results

LINC00665 was expressed at high levels in BC tissues and cells. Upregulated LINC00665 expression correlated with tumor size and tumor, node, and metastasis stages, but not with the age of patients. LINC00665 knockdown inhibited BC cell proliferation, migration, and invasion, whereas it promoted apoptosis. Moreover, bioinformatics analysis and the luciferase reporter assay revealed that LINC00665 bound the microRNA (miR) miR-3619-5p. miR-3619-5p expression correlated negatively with LINC00665 expression in BC tissues. miR-3619-5p overexpression inhibited BC cell proliferation, migration, and invasion, but promoted apoptosis. Simultaneous knockdown of LINC00665 and miR-3619-5p led to increased cell proliferation, migration, and invasion, and inhibited apoptosis. Additionally, catenin beta 1, which encodes the β-catenin protein, was the target gene of miR-3619-5p. β-catenin expression clearly decreased after LINC00665 knockdown and miR-3619-5p overexpression, but increased after simultaneous knockdown of LINC00665 and miR-3619-5p.

Conclusion

LINC00665 knockdown inhibited BC cell proliferation and invasion by binding miR-3619-5p and inhibiting β-catenin expression.

Long non-coding RNA SNHG3, induced by IL-6/STAT3 transactivation, promotes stem cell-like properties of gastric cancer cells by regulating the miR-3619-5p/ARL2 axis

BACKGROUND

Chemotherapy is, next to surgery and radiotherapy, the mainstay regimen for the clinical management of gastric cancer. This therapy is, however, heavily compromised by the acquisition of resistance. Here, we aimed to clarify the potential involvement of long non-coding RNA SNGH3 in the acquisition of cisplatin resistance and stemness in gastric cancer.

METHODS

Cell viability and proliferation were measured using Cell Counting Kit-8 and colony formation assays, respectively. Stem cell-like cell growth was evaluated using a mammosphere formation assay. RNA levels of SNHG2, OCT-4, SOX-2, CD44, miR-3619-5p and ARL2 were determined using qRT-PCR, whereas protein levels of OCT-4, SOX-2, CD44, ARL2, STAT3 and pSTAT3 were determined using Western blotting. Dual luciferase reporter assays were employed to interrogate regulatory interactions between STAT3, SNHG3, miR-3619-5p and ARL2, respectively. Direct binding of STAT3 to the SNHG3 promoter was investigated using a chromatin immunoprecipitation assay.

RESULTS

We found that IL-6 triggered stem cell-like properties in cisplatin-treated gastric cancer cells and activated STAT3, which in turn transcriptionally regulated SNHG3 expression. SNHG3 expression up-regulation positively correlated with cisplatin resistance and stemness of gastric cancer cells, while SNHG3 down-regulation inhibited stem cell-like properties. In addition, we found that SNHG3 up-regulated ARL2 expression through sponging miR-3619-5p, which predominantly mediated the oncogenic properties of SNHG3 in this disease.

CONCLUSIONS

Our data indicate an involvement of aberrant SNHG3 over-expression in the acquisition of both cisplatin resistance and stemness of gastric cancer cells, and of the IL-6/STAT3/SNHG3/miR-3619-5p/ARL2 signaling cascade in the oncogenic properties of SNHG3.

The Role of Non-Coding RNAs as Prognostic Factor, Predictor of Drug Response or Resistance and Pharmacological Targets, in the Cutaneous Squamous Cell Carcinoma

Cutaneous squamous cell carcinoma (CSCC) is the most common keratinocyte-derived skin cancer in the Caucasian population. Exposure to UV radiations (UVRs) represents the main risk carcinogenesis, causing a considerable accumulation of DNA damage in epidermal keratinocytes with an uncontrolled hyperproliferation and tumor development. The limited and rarely durable response of CSCC to the current therapeutic options has led researchers to look for new therapeutic strategies. Recently, the multi-omics approaches have contributed to the identification and prediction of the key role of non-coding RNAs (ncRNAs), such as microRNAs (miRNAs), circularRNAs (circRNAs) and long non-coding RNAs (lncRNAs) in the regulation of several cellular processes in different tumor types, including CSCC. ncRNAs can modulate transcriptional and post-transcriptional events by interacting either with each other or with DNA and proteins, such as transcription factors and RNA-binding proteins. In this review, the implication of ncRNAs in tumorigenesis and their potential role as diagnostic biomarkers and therapeutic targets in human CSCC are reported.

Anti-tumor Drug Targets Analysis: Current Insight and Future Prospect

The incidence and mortality of malignant tumors are on the rise, which has become the second leading cause of death in the world. At present, anti-tumor drugs are one of the most common methods for treating cancer. In recent years, with the in-depth study of tumor biology and related disciplines, it has been gradually discovered that the essence of cell carcinogenesis is the infinite proliferation of cells caused by the disorder of cell signal transduction pathways, followed by a major shift in the concept of anti-tumor drugs research and development. The focus of research and development is shifting from traditional cytotoxic drugs to a new generation of anti-tumor drugs targeted at abnormal signaling system targets in tumor cells. In this review, we summarize the targets of anti-tumor drugs and analyse the molecular mechanisms of their effects, which lay a foundation for subsequent treatment, research and development.

Targeted p21 activation by a new double stranded RNA suppresses human prostate cancer cells growth and metastasis

We have previously demonstrated that miR-1236-3p and its sequence homology dsRNA, dsRNA-245 (which is completely complementary to the p21 promoter) had potential ability to upregulate p21 expression by targeting specific promoter sequence and inhibited bladder cancer (BCa). However, we still know little about the effect of miR-1236-3p on prostate cancer and which dsRNA has an inhibitory effect on prostate cancer (PCa)? Here, we confirmed that miR-1236-3p was decreased in PCa cells and tissues. MiR-1236-3p inhibited PCa cells growth and metastasis by activating p21. Furthermore, we demonstrated that dsP21-245 could inhibit PCa cells growth and metastasis by activating p21 expression. Microarray experiments displayed that miR-1236-3p could affect AKT signaling pathway. We demonstrated that miR-1236-3p significantly suppressed the AKT pathway by inhibiting TLR2 expression while activating p21 expression in PCa cells; this influence was independent of p21 activation. In summary, our results provided evidence that both endogenous and exogenous small RNAs might function to induce p21 expression by interacting with the same promoter region, therefore impeding PCa development. Additionally, our results indicated that miRNA activation could activate the expression of some unknown genes as well as cell signaling pathways. This indicated the need for the further study of clinical applications of RNA activation.

GAS6-AS2 Promotes Hepatocellular Carcinoma via miR-3619-5p/ARL2 Axis Under Insufficient Radiofrequency Ablation Condition

Background: Hepatocellular carcinoma (HCC) is a common malignancy worldwide. Radiofrequency ablation (RFA) is applied for treating HCC; however, insufficient RFA promotes HCC development and accelerates HCC recurrence. Therefore, the molecular functions underlying this process have gradually attracted attention. Aim of the study: We sought to examine whether GAS6-AS2 (also known as GAS6-DT: growth arrest specific 6 divergent transcript) played a role in the development of HCC after insufficient RFA. Methods: The in vitro model was established by heating Huh7 and MHCC97 cells in water bath at 47°C, named as Huh7-H and MHCC97-H. Colony formation, transwell and western blot assays were conducted for functional analysis. Results: GAS6-AS2 was upregulated in Huh7-H and MHCC97-H cells relative to Huh7 and MHCC97 cells. GAS6-AS2 deficiency hampered cell proliferation, migration, invasion, epithelial-mesenchymal transition, and stemness in Huh7-H and MHCC97-H cells. Moreover, microRNA-3619-5p (miR-3619-5p) combined with GAS6-AS2 and ARL2 (ADP ribosylation factor-like GTPase 2) was the target gene of miR-3619-5p. GAS6-AS2 served as the competing endogenous RNA (ceRNA) of ARL2 via absorbing miR-3619-5p. Conclusion: On the whole, present study uncovered a novel ceRNA mechanism of GAS6-AS2/miR-3619-5p/ARL2 in HCC after insufficient RFA, which might shed a new insight into treatment of HCC after insufficient RFA.

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

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

MicroRNAs target the Wnt/β‑catenin signaling pathway to regulate epithelial‑mesenchymal transition in cancer (Review)

Epithelial‑mesenchymal transition (EMT), during which cancer cells lose the epithelial phenotype and gain the mesenchymal phenotype, has been verified to result in tumor migration and invasion. Numerous studies have shown that dysregulation of the Wnt/β‑catenin signaling pathway gives rise to EMT, which is characterized by nuclear translocation of β‑catenin and E‑cadherin suppression. Wnt/β‑catenin signaling was confirmed to be affected by microRNAs (miRNAs), several of which are down‑ or upregulated in metastatic cancer cells, indicating their complex roles in Wnt/β‑catenin signaling. In this review, we demonstrated the targets of various miRNAs in altering Wnt/β‑catenin signaling to promote or inhibit EMT, which may elucidate the underlying mechanism of EMT regulation by miRNAs and provide evidence for potential therapeutic targets in the treatment of invasive tumors.

circ_0084927 promotes cervical carcinogenesis by sponging miR-1179 that suppresses CDK2, a cell cycle-related gene

Background

Cervical cancer (CC) is a malignant tumor found in the lowermost part of the womb. Evolving studies on CC have reported that circRNA plays a crucial role in CC progression. In this study, we investigated the main function of a novel circRNA, circ_0084927, and its regulatory network in CC development.

Methods

qRT-PCR was applied to evaluate the expression of circ_0084927, miR-1179, and CDK2 mRNA in CC tissues and cells. Dual-luciferase reporting experiments and RNA immunoprecipitation (RIP) assay were conducted to validate the target relationship of miR-1179 with circ_0084927 and CDK2 mRNA. CCK-8 and BrdU assays were also used to evaluate CC cell proliferation. The adhesion and apoptosis phenotypes of CC cells were measured using cell–matrix adhesion and caspase 3 activation assay. Flow cytometry was also employed to detect the CC cell cycle.

Results

Our results indicated that circ_0084927 was up-regulated in CC tissues and cells. Findings also revealed that circ_0084927 silence inhibited CC cell proliferation and adhesion while facilitating apoptosis and triggering cell cycle arrest. However, miR-1179 down-regulation appeared in CC tissues. Apart from observing that circ_0084927 abolished miR-1179’s inhibitory effects on cell proliferation and adhesion, it was found that CDK2 was up-regulated in CC tissues and was instrumental in cancer promotion. Also observed was that miR-1179 directly targeted CDK2, thereby inhibiting CDK2’s promotion on the malignant phenotypes of CC cells. Lastly, results indicated that circ_0084927 revoked the inhibitory effect of miR-1179 on CDK2 by sponging miR-1179.

Conclusion

circ_0084927 promoted cervical carcinogenesis by sequestering miR-1179, which directly targeted CDK2. Our results also provided novel candidate targets for CC treatment in that it revealed the circ_0084927/miR-1179/CDK2 regulatory network that strengthened CC aggressiveness.

DGCR5 Promotes Gallbladder Cancer by Sponging MiR-3619-5p via MEK/ERK1/2 and JNK/p38 MAPK Pathways

Gallbladder cancer (GBC) is a highly aggressive malignant cancer with poor prognosis. Long noncoding RNA (lncRNA) DiGeorge syndrome critical region gene (DGCR5) has been reported to participate in various types of cancers, but its role in GBC remains largely unknown. This study aimed to explore the functions and mechanisms of DGCR5 in GBC. Here, we found that DGCR5 was upregulated in GBC tissues and cell lines. Through functional experiments, it was demonstrated that silence of DGCR5 significantly suppressed the cell proliferation, migration, invasion, and induced apoptosis and cell cycle arrest in GBC cells. In addition, miR-3619-5p was predicted and further verified as the target of DGCR5. Moreover, miR-3619-5p was observed downregulated in GBC tissues and cell lines, and miR-3619-5p mimics repressed the GBC cell proliferation, migration, invasion and could be rescued by DGCR5 overexpression. Mechanistically, it was found that DGCR5 knockdown and miR-3619-5p mimics inactivated the MEK/ERK1/2 and JNK/p38 MAPK pathways. In addition, rescue experiments indicated that inhibition of MEK/ERK1/2 and JNK/p38 MAPK pathways could reverse the effects of DGCR5 overexpression on cell proliferation, migration and invasion. Finally, xenograft model assay was used to validate that knockdown of DGCR5 suppressed GBC via regulating MEK/ERK1/2 and JNK/p38 MAPK pathways in vivo. Taken together, it was uncovered in our study that DGCR5 exerts an oncogenic role by sponging miR-3619-5p and activating MEK/ERK1/2 and JNK/p38 MAPK pathways in GBC progression.

STAT4-mediated down-regulation of miR-3619-5p facilitates stomach adenocarcinoma by modulating TBC1D10B

BACKGROUND

MicroRNAs (miRNAs) as the subtype of non-coding RNAs are revealed to be crucial players in cellular activities. It has been reported that miR-3619-5p functions as a tumor inhibitor in several cancers. However, the connection between miR-3619-5p and stomach adenocarcinoma (STAD) remains to be discovered.

AIM OF THE STUDY

The purpose of the study is to figure out the role and molecular regulation mechanism of miR-3619-5p in STAD.

METHODS

The expression of miR-3619-5p was evaluated via qRT-PCR analysis. Gain-of-function experiments demonstrated the effects of miR-3619-5p on cellular functions. The upper-stream transcription factor STAT4 and downstream target gene TBC1D10B of miR-3619-5p were identified by bioinformatic analysis. The binding and interaction between the indicated molecules were verified by RNA pull-down and luciferase reporter assays.

RESULTS

The expression of miR-3619-5p was prominently down-regulated in STAD cells and tissues. MiR-3619-5p suppresses cell proliferation, migration, invasion and tumor growth in STAD. Further, STAT4 bound with miR-3619-5p promoter and inhibited its transcription. MiR-3619-5p was also recognized to modulate STAD progression through the regulation of downstream target gene TBC1D10B.

CONCLUSION

STAT4-mediated miR-3619-5p controls STAD carcinogenesis and progression through modulating TBC1D10B expression, which may provide a novel insight for researching the STAD-related molecular mechanism.

Inhibiting effect of MicroRNA-3619-5p/PSMD10 axis on liver cancer cell growth in vivo and in vitro

AIMS

Liver cancer is one of the leading causes of cancer death worldwide owing to its delayed diagnosis and absence of efficient treatment at advanced TNM stages. Increasing evidence demonstrated that microRNAs are implicated in tumorgenesis and cancer development by regulating cancer-related proteins. This study aimed to explore the effect of miR-3619-5p on cell growth in liver cancer.

MAIN METHODS

The effect of miR-3619-5p on cell proliferation was measured by quantitative real-time PCR, MTT assay, flow cytometry, and Immunofluorescence assay. The interaction between miR-3619-5p and PSMD10 was validated using dual-luciferase. The expression of PSMD10 and Ki67 was further determined by immunohistochemistry.

KEY FINDINGS

MiR-3619-5p over-expression remarkably inhibited cell proliferation and induced G1 phase arrest, accompanied with reduced expression of proliferating cell nuclear antigen. The expression of miR-3619-5p was negatively correlated to that of PSMD10, and PSMD10 was validated to be a downstream target of miR-3619-5p. Moreover, miR-3619-5p induced suppressed proliferation and G1 phase arrest were abrogated by elevated the expression of PSMD10 in liver cancer cells. PSMD10 over-expression also induced phosphorylation of signal transducer and activator of transcription 3 (STAT3) and retinoblastoma protein (Rb1). Besides, elevated cyclin A, cyclin D1 and cyclin E expression supported that PSMD10 promoted the progress of cell cycle. In addition, miR-3619-5p inhibited tumor growth in vivo by targeting PSMD10, accompanied with blocked cell cycle.

SIGNIFICANCE

In conclusion, our findings revealed that miR-3619-5p inhibits cancer cell proliferation by targeting PSMD10, and miR-3619-5p as a potential therapeutic target for the treatment of liver cancer.

MSC-induced lncRNA HCP5 drove fatty acid oxidation through miR-3619-5p/AMPK/PGC1α/CEBPB axis to promote stemness and chemo-resistance of gastric cancer

Chemotherapy is the first-tier treatment regime for gastric cancer (GC) patients at advance stages. Mesenchymal stem cell (MSC) cam affect drug-resistance of GC cells in tumor microenvironment, but the detailed mechanism remains poorly understood. Present study aimed to investigate the regulation of MSC-induced long non-coding RNA (lncRNA) in GC. Dysregulated lncRNAs in GC were analyzed based on GEO data. Stemness and drug-resistance of GC cells were detected by sphere formation, colony formation, CCK-8, and flow cytometry analyses. MicroRNA (miRNA)-related pathways were analyzed by online KEGG analysis tool DAVID6.8. Molecular interactions were determined by luciferase reporter assay, pulldown, RNA immunoprecipitation (RIP), chromatin immunoprecipitation (ChIP), and co-immunoprecipitation (CoIP). Results revealed that MSC co-culture improved stemness and drug-resistance of GC cells. LncRNA histocompatibility leukocyte antigen complex P5 (HCP5) was induced in GC cells by MSC co-culture, contributing to stemness and drug-resistance. Mechanistically, HCP5 sequestered miR-3619-5p and upregulated PPARG coactivator 1 alpha (PPARGC1A), increasing transcription complex Peroxisome proliferator activated receptor (PPAR) coactivator-1α (PGC1α)/CEBPB and transcriptionally inducing carnitine palmitoyltransferase 1 (CPT1), which prompted the fatty acid oxidation (FAO) in GC cells. In conclusion, MSC-induced lncRNA HCP5 drove FAO through miR-3619-5p/AMPK/PGC1α/CEBPB axis to promote stemness and chemo-resistance of GC, indicating that targeting HCP5 was a novel approach to enhancing the efficacy of chemotherapy in GC.

Molecular principles of metastasis: a hallmark of cancer revisited

Metastasis is the hallmark of cancer that is responsible for the greatest number of cancer-related deaths. Yet, it remains poorly understood. The continuous evolution of cancer biology research and the emergence of new paradigms in the study of metastasis have revealed some of the molecular underpinnings of this dissemination process. The invading tumor cell, on its way to the target site, interacts with other proteins and cells. Recognition of these interactions improved the understanding of some of the biological principles of the metastatic cell that govern its mobility and plasticity. Communication with the tumor microenvironment allows invading cancer cells to overcome stromal challenges, settle, and colonize. These characteristics of cancer cells are driven by genetic and epigenetic modifications within the tumor cell itself and its microenvironment. Establishing the biological mechanisms of the metastatic process is crucial in finding open therapeutic windows for successful interventions. In this review, the authors explore the recent advancements in the field of metastasis and highlight the latest insights that contribute to shaping this hallmark of cancer.

M6A-mediated upregulation of LINC00958 increases lipogenesis and acts as a nanotherapeutic target in hepatocellular carcinoma

BACKGROUND

Long non-coding RNAs (lncRNAs) possess significant regulatory functions in multiple biological and pathological processes, especially in cancer. Dysregulated lncRNAs in hepatocellular carcinoma (HCC) and their therapeutic applications remain unclear.

METHODS

Differentially expressed lncRNA profile in HCC was constructed using TCGA data. LINC00958 expression level was examined in HCC cell lines and tissues. Univariate and multivariate analyses were performed to demonstrate the prognostic value of LINC00958. Loss-of-function and gain-of-function experiments were used to assess the effects of LINC00958 on cell proliferation, motility, and lipogenesis. Patient-derived xenograft model was established for in vivo experiments. RNA immunoprecipitation, dual luciferase reporter, biotin-labeled miRNA pull-down, fluorescence in situ hybridization, and RNA sequencing assays were performed to elucidate the underlying molecular mechanisms. We developed a PLGA-based nanoplatform encapsulating LINC00958 siRNA and evaluated its superiority for systemic administration.

RESULTS

We identified a lipogenesis-related lncRNA, LINC00958, whose expression was upregulated in HCC cell lines and tissues. High LINC00958 level independently predicted poor overall survival. Functional assays showed that LINC00958 aggravated HCC malignant phenotypes in vitro and in vivo. Mechanistically, LINC00958 sponged miR-3619-5p to upregulate hepatoma-derived growth factor (HDGF) expression, thereby facilitating HCC lipogenesis and progression. METTL3-mediated N⁶-methyladenosine modification led to LINC00958 upregulation through stabilizing its RNA transcript. A PLGA-based nanoplatform loaded with si-LINC00958 was developed for HCC systemic administration. This novel drug delivery system was controlled release, tumor targeting, safe, and presented satisfactory antitumor efficacy.

CONCLUSIONS

Our results delineate the clinical significance of LINC00958 in HCC and the regulatory mechanisms involved in HCC lipogenesis and progression, providing a novel prognostic indicator and promising nanotherapeutic target.

Epigenetics of Bladder Cancer: Where Biomarkers and Therapeutic Targets Meet

Bladder cancer (BC) is the most common neoplasia of the urothelial tract. Due to its high incidence, prevalence, recurrence and mortality, it remains an unsolved clinical and social problem. The treatment of BC is challenging and, although immunotherapies have revealed potential benefit in a percentage of patients, it remains mostly an incurable disease at its advanced state. Epigenetic alterations, including aberrant DNA methylation, altered chromatin remodeling and deregulated expression of non-coding RNAs are common events in BC and can be driver events in BC pathogenesis. Accordingly, these epigenetic alterations are now being used as potential biomarkers for these disorders and are being envisioned as potential therapeutic targets for the future management of BC. In this review, we summarize the recent findings in these emerging and exciting new aspects paving the way for future clinical treatment of this disease.

LINC01410/miR-3619-5p/FOXM1 Feedback Loop Regulates Papillary Thyroid Carcinoma Cell Proliferation and Apoptosis

Backgrounds: Thyroid cancer (TC) is a prevalent type of cancer in endocrine system. Past decades have seen the rising mortality and morbidity of TC. Long noncoding RNAs are renowned modulators of cancer onset and progression as validated by mounting studies. Long intergenic non-protein coding RNA 1410 (LINC01410) has been suggested as tumor-promoting gene in colon cancer and gastric cancer, but its role in TC is elusive. This study investigated the impact and mechanism of LINC01410 in TC. Materials and Methods: RT-qPCR and western blot were used to detect gene expression levels. Cell counting kit-8 (CCK-8) and ethynyl-2'-deoxyuridine (EdU) assays were used to determine proliferation. Caspase-3 activity assay was used to examine apoptosis. Intermolecular interaction was investigated by luciferase reporter assay and chromatin immunoprecipitation (ChIP) assay. Results: We confirmed the elevation of LINC01410 expression in TC cells. Loss-of-function experiments indicated that LINC01410 knockdown suppressed proliferation and facilitated apoptosis in TC. Mechanism research illustrated that LINC01410 positively regulated forkhead box M1 (FOXM1) expression through targeting miR-3619-5p, and that FOXM1 in turn transcriptionally activated LINC01410. Rescue experiments validated that LINC01410 regulated TC proliferation and apoptosis through miR-3619-5p/FOXM1. Conclusions: This study demonstrated that LINC01410/miR-3619-5p/FOXM1 positive feedback loop regulated cell proliferation and apoptosis in TC, shedding a light on the molecular target identification and promising treatment improvement in TC.

WNT/β-catenin signaling in urothelial carcinoma of bladder

Urothelial carcinoma of bladder is the second most prevalent genitourinary disease. It is a highly heterogeneous disease as it represents a spectrum of neoplasms, including non-muscle invasive bladder cancer (NMIBC), muscle invasive bladder cancer (MIBC) and metastatic lesions. Genome-wide approaches and candidate gene analysis suggest that malignant transformation of the bladder is multifactorial and a multitude of genes are involved in the development of MIBC or NMIBC phenotypes. Wnt signaling is being examined to control and maintain balance between stemness and differentiation in adult stem cell niches. Owing to its participation in urothelial development and maintenance of adult urothelial tissue homeostasis, the components of Wnt signaling are reported as an important diagnostic and prognostic markers as well as novel therapeutic targets. Mutations/epigenetic alterations in the key molecules of Wnt/β-catenin canonical pathway have been linked with tumorigenesis, development of drug resistance and enhanced survival. Present review extends our understanding on the functions of key regulatory molecules of canonical Wnt/β-catenin pathway in urothelial tumorigenesis by inducing cancer stem cell phenotype (UCSCs). UCSCs may be responsible for tumor heterogeneity, high recurrence rates and complex biological behavior of bladder cancer. Therefore, understanding the role of UCSCs and the regulatory mechanisms that are responsible for high relapse rates and metastasis could help to develop pathway inhibitors and augment current therapies. Potential implications in the treatment of urothelial carcinoma of bladder by targeting this pathway primarily in UCSCs as well as in bulk tumor population that are responsible for high relapse rates and metastasis may facilitate potential therapeutic avenues and better prognosis.

The TGF-β/Smad Pathway Inhibitor SB431542 Enhances The Antitumor Effect Of Radiofrequency Ablation On Bladder Cancer Cells

Background

Despite progress achieved in bladder cancer (BC) treatment, the prognosis of patients with advanced BC (ie, metastasized from the bladder to other organs) is poor. Although mortality in cases of low-grade BC is rare, the treatment, such as a radical cystectomy, often has a serious impact on the quality of life. Thus, research is needed to identify more effective treatment strategies and this work is aiming to examine the potential application of combination of radiofrequency ablation (RFA) and SB435142, a inhibitor of transforming growth factor β (TGFβ)/Smad pathway.

Methods

BC cells were transplanted into nude mice (thymusdeficiency Bal B/c) to form subcutaneous tumors. The mice with subcutaneous tumors were then treated with RFA and oral administration of SB431542, an inhibitor of TGFβ/Smad signaling pathway. The antitumor effect of RFA was measured by tumor proliferation curves and micro-positron emission computed tomography (micro-PET). The effect of SB431542 on epithelial-mesenchymal transition (EMT) related regulators in subcutaneous tumor tissues formed by BC cells were examined by quantitative real-time polymerase chain reaction (qPCR) experiments.

Results

The SB431542 treatment enhanced the antitumor effect of RFA on subcutaneous growth of BCs. SB431542 also decreased EMT-related regulators in subcutaneous tumor tissues formed by BC cells in nude mice.

Conclusion

SB431542 enhances the effect of RFA on BC.