miR-29c-3p regulates DNMT3B and LATS1 methylation to inhibit tumor progression in hepatocellular carcinoma

Targeting Regulatory Noncoding RNAs in Human Cancer: The State of the Art in Clinical Trials

Noncoding RNAs (ncRNAs) are a heterogeneous group of RNA molecules whose classification is mainly based on arbitrary criteria such as the molecule length, secondary structures, and cellular functions. A large fraction of these ncRNAs play a regulatory role regarding messenger RNAs (mRNAs) or other ncRNAs, creating an intracellular network of cross-interactions that allow the fine and complex regulation of gene expression. Altering the balance between these interactions may be sufficient to cause a transition from health to disease and vice versa. This leads to the possibility of intervening in these mechanisms to re-establish health in patients. The regulatory role of ncRNAs is associated with all cancer hallmarks, such as proliferation, apoptosis, invasion, metastasis, and genomic instability. Based on the function performed in carcinogenesis, ncRNAs may behave either as oncogenes or tumor suppressors. However, this distinction is not rigid; some ncRNAs can fall into both classes depending on the tissue considered or the target molecule. Furthermore, some of them are also involved in regulating the response to traditional cancer-therapeutic approaches. In general, the regulation of molecular mechanisms by ncRNAs is very complex and still largely unclear, but it has enormous potential both for the development of new therapies, especially in cases where traditional methods fail, and for their use as novel and more efficient biomarkers. Overall, this review will provide a brief overview of ncRNAs in human cancer biology, with a specific focus on describing the most recent ongoing clinical trials (CT) in which ncRNAs have been tested for their potential as therapeutic agents or evaluated as biomarkers.

DNA Methylation Regulatory Axis miR-29b-3p/DNMT3B Regulates Liver Regeneration Process by Altering LATS1

DNA methylation is a crucial epigenetic alteration involved in diverse biological processes and diseases. Hippo signalling pathway is a key signalling regulatory network in the growth and development of tissues and organs. Nevertheless, the precise role of DNA methylation and Hippo signalling pathway during liver regeneration (PH) is still unclear. In this study, we investigated the regulatory mechanism of LATS1, a pivotal protein in the Hippo signalling pathway, on liver regeneration and explored the specific mechanism of DNA methylation regulating LATS1. To analyse the regulation of LATS1 by DNA methylation, following 2/3 partial hepatectomy (PH) in liver-specific AAV-8 shDNMT3B deleted mice (DNMT3B, KD) mice and sex-matched AAV-8 shControl (Control). We determined that DNMT3B regulates the protein expression of LATS1 by DNA methylation. miR-29b-3p significantly regulates the expression of DNMT3B and alters LATS1 expression to inactivate the Hippo signalling pathway, thereby reducing the expression of cell proliferation and cycle proteins and inhibiting liver regeneration. Our results indicated that the miR-29b-3p/DNMT3B regulatory axis influences LATS1 expression through DNA methylation, and thereby promotes liver regeneration.

miR-143-3p/TET1 Axis Regulates GPC1 Through DNA Methylation and Impairs the Malignant Biological Behaviour of HCC via the Hippo Signalling Pathway

Hepatocellular carcinoma (HCC) is a malignant tumour that poses a serious threat to human health and places a heavy burden on individuals and society. However, the role of GPC1 in the malignant progression of HCC is unknown. In this study, we analysed the expression of GPC1 in HCC, and its association with poor patient prognosis. The effects of GPC1 on the proliferation, invasion and migration of HCC were analysed through cellular functional experiments in vitro and in vivo. Mechanistically, DNA methylation of GPC1 was analysed by DNA extraction, methylation-specific PCR and bisulfite Sanger sequencing (BSP), and the target genes TET1 and miRNA regulating DNA methylation of GPC1 were found through the bioinformatics database. The results revealed that GPC1 was highly expressed in HCC, and its high expression was significantly associated with poor prognosis of HCC patients. Inhibiting the expression of GPC1 can inhibit the proliferation, invasion and migration of HCC cells. GPC1 was hypomethylated in HCC, and its methylation level was regulated by TET1. miR-143-3p can significantly regulated the expression of TET1 and affect the methylation level and protein expression of GPC1. Furthermore, GPC1 also affects the malignant biological behaviour of HCC by regulating the expression of Hippo signalling pathway. In summary, miR-143-3p regulates the expression of TET1, affects the expression of GPC1 through DNA methylation and regulates the malignant progression of HCC via Hippo signalling pathway.

Interaction of noncoding RNAs with hippo signaling pathway in cancer cells and cancer stem cells

The Hippo signaling pathway has a regulatory function in the organogenesis process and cellular homeostasis, switching the cascade reactions of crucial kinases acts to turn off/on the Hippo pathway, altering the downstream gene expression and thereby regulating proliferation, apoptosis, or stemness. Disruption of this pathway can lead to the occurrence of various disorders and different types of cancer. Recent findings highlight the importance of ncRNAs, such as microRNA, circular RNA, and lncRNAs, in modulating the Hippo pathway. Defects in ncRNAs can disrupt Hippo pathway balance, increasing tumor cells, tumorigenesis, and chemotherapeutic resistance. This review summarizes ncRNAs' inhibitory or stimulatory role in - Hippo pathway regulation in cancer and stem cells. Identifying the relation between ncRNAs and the components of this pathway could pave the way for developing new biomarkers in the treatment and diagnosis of cancers.

FAM136A as a Diagnostic Biomarker in Esophageal Cancer: Insights into Immune Infiltration, m6A Modification, Alternative Splicing, Cuproptosis, and the ceRNA Network

FAM136A promotes the progression and metastasis of various tumors. However, there are few studies on the role of FAM136A in esophageal cancer (ESCA). The TCGA, GTEx, and GEO databases are employed to analyze the expression of FAM136A in ESCA, and qPCR and TMA experiments are performed for validation. Enrichment analyzes are performed to investigate the association of FAM136A expression with immune features, m6A modification, alternative splicing, cuproptosis, and the ceRNA network via bioinformatics analysis. FAM136A is highly expressed in ESCA and correlated with lymph node metastasis and overall survival (OS). Bioinformatics analysis suggested that FAM136A may participate in the following processes to promote ESCA development and progression: 1) Promotion of mast cells infiltration to influence the ESCA immune microenvironment, 2) HNRNPC upregulation to regulate m6A modification, 3) ALYREF upregulation to increase the occurrence of retained intron (RI) events, 4) CDK5RAP1 upregulation to achieve inhibition of tumor cell apoptosis, and 5) promotion of ESCA progression through the lncRNA SNHG15/hsa-miR-29c-3p/FAM136A ceRNA network. FAM136A is a potential biomarker for ESCA diagnosis and treatment response evaluation, and the underlying mechanisms may be associated with immune infiltration, m6A modification, alternative splicing, cuproptosis, and the ceRNA regulatory network.

Downregulating DNA methyltransferase 3B by suppressing the PI3K/Akt signaling pathway enhances the chemosensitivity of glioblastoma to temozolomide

Glioblastoma (GBM) is the most common malignant brain tumor and has the poorest prognosis attributed to its chemoresistance to temozolomide (TMZ), the first-line drug for treating GBM. TMZ resistance represents a significant obstacle to successful GBM treatment, necessitating the development of new strategies to overcome this resistance and augment the chemosensitivity of GBM cells to TMZ. This study established a TMZ-resistant U251 (U251-TMZ) cell line by exposing it to increasing doses of TMZ in vitro. We focused on the DNA methyltransferase 3B (DNMT3B) gene, phosphorylated Akt (p-Akt), total Akt (t-Akt), phosphorylated PI3K (p-PI3K), and total PI3K (t-PI3K) protein expression. Results showed that the DNMT3B gene was significantly upregulated in the U251-TMZ cell line. The p-Akt and p-PI3K protein expression in U251-TMZ cells was also significantly elevated. Moreover, we found that DNMT3B downregulation was correlated with the increased chemosensitivity of GBM cells to TMZ. LY294002 suppressed the PI3K/Akt signaling pathway, leading to a notable inhibition of PI3K phosphorylation and a significant decrease in DNMT3B expression in U251-TMZ cells. Given that DNMT3B expression is mediated by the PI3K/Akt signaling pathway, its downregulation further increased the chemosensitivity of GBM cells to TMZ and therefore is a promising therapeutic for GBM treatment. Our results suggested that DNMT3B downregulation can inhibit the proliferation of GBM cells and induce GBM cell apoptosis in vitro. In addition, the PI3K/Akt signaling pathway plays an important role in the chemosensitivity of GBM cells to TMZ by regulating DNMT3B expression.

E3 ubiquitin ligase TRIM31: A potential therapeutic target

Ubiquitination is a key mechanism for post-translational protein modification, affecting protein localization, metabolism, degradation and various cellular physiological processes. Dysregulation of ubiquitination is associated with the pathogenesis of various diseases, such as tumors and cardiovascular diseases, making it a primary area of interest in biochemical research and drug development endeavors. E3 ubiquitin ligases play a pivotal role in modulating the ubiquitination of substrate proteins through their unique recognition functions. TRIM31, a member of the TRIM family of E3 ubiquitin ligases, is aberrantly expressed in different pathophysiological conditions. The biological function of TRIM31 is associated with the occurrence and development of diverse diseases. TRIM31 has been demonstrated to inhibit inflammation by promoting ubiquitin-proteasome-mediated degradation of the sensing protein NLRP3 in the inflammasome. TRIM31 mediates ubiquitination of MAVS, inducing the formation of prion-like aggregates, and triggering innate antiviral immune responses. TRIM31 is also implicated in tumor pathophysiology through its ability to promote ubiquitination of the tumor suppressor protein p53. These findings indicate that TRIM31 is a potential therapeutic target, and subsequent in-depth research of TRIM31 is anticipated to provide information on its clinical application in therapy.

Characterizing expression changes in noncoding RNAs during aging and heterochronic parabiosis across mouse tissues

Molecular mechanisms of organismal and cell aging remain incompletely understood. We, therefore, generated a body-wide map of noncoding RNA (ncRNA) expression in aging (16 organs at ten timepoints from 1 to 27 months) and rejuvenated mice. We found molecular aging trajectories are largely tissue-specific except for eight broadly deregulated microRNAs (miRNAs). Their individual abundance mirrors their presence in circulating plasma and extracellular vesicles (EVs) whereas tissue-specific ncRNAs were less present. For miR-29c-3p, we observe the largest correlation with aging in solid organs, plasma and EVs. In mice rejuvenated by heterochronic parabiosis, miR-29c-3p was the most prominent miRNA restored to similar levels found in young liver. miR-29c-3p targets the extracellular matrix and secretion pathways, known to be implicated in aging. We provide a map of organism-wide expression of ncRNAs with aging and rejuvenation and identify a set of broadly deregulated miRNAs, which may function as systemic regulators of aging via plasma and EVs.

miR-29c-3p acts as a tumor promoter by regulating β-catenin signaling through suppressing DNMT3A, TET1 and HBP1 in ovarian carcinoma

Ovarian Carcinoma (OvCa) is characterized by rapid and sustained growth, activated invasion and metastasis. Studies have shown that microRNAs recruit and alter the expression of key regulators to modulate carcinogenesis. Here, we find that miR-29c-3p is increased in benign OvCa and malignant OvCa compared to normal ovary. Univariate and multivariate analyses report that miR-29c-3p overexpression is associated with poor prognosis in OvCa. Furthermore, we investigate that expression of miR-29c-3p is inversely correlated to DNA methyltransferase (DNMT) 3 A and Ten-Eleven-Translocation enzyme TET1. The high-throughput mRNA sequencing, bioinformatics analysis and pharmacological studies confirm that aberrant miR-29c-3p modulates tumorigenesis in OvCa cells, including epithelial-mesenchymal transition (EMT), proliferation, migration, and invasion. This modulation occurs through the regulation of β-catenin signaling by directly targeting 3'UTR of DNMT3A, TET1 and the HMG box transcription factor HBP1 and suppressing their expression. The further 3D spheres assay clearly shows the regulatory effects of miR-29c-3p on OvCa tumorigenesis. Additionally, the receiver operating characteristic (ROC) curve analysis of miR-29c-3p and the clinical detection/diagnostic biomarker CA125 suggests that miR-29c-3p may be conducive for clinical diagnosis or co-diagnosis of OvCa. These findings support miR-29c-3p functions as a tumor promoter by targeting its functional targets, providing new potential biomarker (s) for precision medicine strategies in OvCa.

miR-29c-3p represses the angiogenesis of esophageal squamous cell carcinoma by targeting SERPINH1 to regulate the Wnt signaling pathway

PURPOSE

Esophageal squamous cell carcinoma (ESCC) is characterized by early metastasis and late diagnosis. miR-29c-3p is confirmed to repress angiogenesis in multiple tumor types. Yet, the functions of miR-29c-3p in the mechanism of ESCC angiogenesis, which were not sufficiently explored previously, were exactly what we investigated here at the molecular level.

METHODS

The mRNA level of miR-29c-3p and Serpin peptidase inhibitor clade H member 1 (SERPINH1) in ESCC tissues were assessed via bioinformatics analysis. Thereafter, miR-29c-3p and SERPINH1 (HSP47) mRNA level in ESCC cell lines was evaluated via quantitative real-time polymerase chain reaction. The effects of abnormal miR-29c-3p and SERPINH1 expression on ESCC cell viability, proliferation, migration, invasion, and HUVEC angiogenesis were examined via CCK8, colony formation, transwell, and angiogenesis assays, respectively. The protein levels of SERPINH1, vascular endothelial growth factor-A (VEGFA), Wnt-1, ?-catenin, and p-?-catenin were evaluated via Western blot. Expression of VEGFA secreted by ESCC cells was measured via enzyme-linked immunosorbent assay. Treatment with the Wnt activator BML-284 further revealed the way miR-29c-3p mediated the Wnt signaling pathway and its effects on angiogenesis.

RESULTS

Herein, we revealed a decrease of miR-29c-3p expression in ESCC tissues and cells, while the overexpressed miR-29c-3p could remarkably suppress ESCC cell progression, as well as HUVEC angiogenesis. Meanwhile, overexpressed miR-29c-3p notably downregulated VEGFA and repressed the Wnt signaling pathway. Treatment with the Wnt activator BML-284 could reverse the inhibition of HUVEC angiogenesis caused by miR-29c-3p. SERPINH1 was a downstream target of miR-29c-3p. SERPINH1 knockdown suppressed the malignant phenotypes of ESCC cells and impeded the Wnt signaling activation, while such suppression was reversed through miR-29c-3p inhibitor.

CONCLUSIONS

We confirmed the mechanism that miR-29c-3p targeted SERPINH1, thus regulating angiogenesis in ESCC through the Wnt signaling pathway. It improves the understanding of angiogenesis in ESCC and offers new ideas for the research of ESCC treatment strategies in the future.

Non-coding RNAs/DNMT3B axis in human cancers: from pathogenesis to clinical significance

Cancer is a complex disease with many contributing factors, and researchers have gained extensive knowledge that has helped them understand the diverse and varied nature of cancer. The altered patterns of DNA methylation found in numerous types of cancer imply that they may play a part in the disease's progression. The human cancer condition involves dysregulation of the DNA methyltransferase 3 beta (DNMT3B) gene, a prominent de novo DNA methyltransferase, and its abnormal behavior serves as an indicator for tumor prognosis and staging. The expression of non-coding RNAs (ncRNAs), which include microRNAs (miRNA), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), is critical in controlling targeted gene expression and protein translation and their dysregulation correlates with the onset of tumors. NcRNAs dysregulation of is a critical factor that influences the modulation of several cellular characteristics in cancerous cells. These characteristics include but are not limited to, drug responsiveness, angiogenesis, metastasis, apoptosis, proliferation, and properties of tumor stem cell. The reciprocal regulation of ncRNAs and DNMT3B can act in synergy to influence the destiny of tumor cells. Thus, a critical avenue for advancing cancer prevention and treatment is an inquiry into the interplay between DNMT3B and ncRNAs. In this review, we present a comprehensive overview of the ncRNAs/DNMT3B axis in cancer pathogenesis. This brings about valuable insights into the intricate mechanisms of tumorigenesis and provides a foundation for developing effective therapeutic interventions.

The bidirectional interplay between ncRNAs and methylation modifications in gastrointestinal tumors

The aberrant expression of methylation and ncRNAs, two crucial regulators of epigenetic modifications, has been widely demonstrated in cancer. The complex interplay between them is essential in promoting malignant phenotype, poor prognosis, and drug resistance in GI tumors (including esophageal, gastric, colorectal, liver, and pancreatic cancers). Therefore, we summarize the interrelation process between ncRNAs and methylation modifications in GI tumors, including the detailed mechanism of methylation enzyme regulation of ncRNAs, the molecular mechanism of ncRNAs regulation of methylation modifications, and the correlation between the interactions between ncRNAs and methylation modifications and clinical features of tumors. Finally, we discuss the potential value of ncRNAs and methylation modifications in clinical diagnosis and therapy.

Epigenetic deregulation of MLF1 drives intrahepatic cholangiocarcinoma progression through EGFR/AKT and Wnt/β-catenin signaling

BACKGROUND

Intrahepatic cholangiocarcinoma (iCCA) is an aggressive malignancy with multiple etiologies and is largely refractory to current treatment strategies. Myeloid leukemia factor 1 (MLF1) is associated with human cancer progression. Nevertheless, the function of MLF1 in iCCA remains unknown.

METHODS

We performed expression analyses of MLF1 in human iCCA. In vitro and in vivo experiments were conducted to investigate the role of MLF1 in iCCA progression. The upstream regulatory mechanism of MLF1 upregulation in iCCA was deciphered by luciferase and DNA methylation analyses.

RESULTS

MLF1 was significantly upregulated in clinical iCCA tissue specimens and human iCCA cell lines. MLF1 was positively correlated with KRT19 and MUC1 expression and epithelial-mesenchymal transition (EMT) gene set enrichment score in clinical iCCA. High MLF1 expression was independently associated with worse prognoses in iCCA patients after curative resection. In addition, experimental knockdown of MLF1 attenuated, while overexpression of MLF1 promoted the proliferation, invasiveness, and growth of iCCA cells in vitro and in vivo. Mechanically, MLF1 comodulated EGFR/AKT and Wnt/β-catenin signalings through regulating EGFR, AKT, WNT3, and p-GSK3β expression. Promoter CpG sites' hypermethylation-induced downregulation of miR-29c-3p contributed to MLF1 upregulation in iCCA patients. The upregulation of DNA methyltransferase (DNMT)1, 3A, and 3B downregulated miR-29c-3p by dictating promoter DNA methylation pattern. MiR-29c-3p showed therapeutic potential by targeting MLF1 in iCCA.

CONCLUSIONS

Our results demonstrated that hypermethylation-mediated miR-29c-3p downregulation contributes to MLF1 upregulation in iCCA, which resulted in tumor cells' proliferation and metastasis through comodulating EGFR/AKT and Wnt/β-catenin signalings.

Downregulation of fibrosis related hsa-miR-29c-3p in human CAKUT

Congenital anomalies of the kidney and urinary tract (CAKUT) represent structural and functional urinary system malformations and take place as one of the most common congenital malformations with an incidence of 1:500. Ureteral obstruction-induced hydronephrosis is associated with renal fibrosis and chronic kidney diseases in the pediatric CAKUT. We aimed to construct interaction network of previously bioinformatically associated miRNAs with CAKUT differentially expressed genes in order to prioritize those associated with fibrotic process and to experimentally validate the expression of selected miRNAs in CAKUT patients compared to control group. We constructed interaction network of hsa-miR-101-3p, hsa-miR-101-5p and hsa-miR-29c-3p that showed significant association with fibrosis. The top enriched molecular pathway was extracellular matrix-receptor interaction (adjusted p = .0000263). We experimentally confirmed expression of three miRNAs (hsa-miR-29c-3p, hsa-miR-101-3p and hsa-miR-101-5p) in obstructed ureters (ureteropelvic junction obstruction and primary obstructive megaureter) and vesicoureteral reflux. The hsa-miR-29c-3p was shown to have lower expression in both patient groups compared to controls. Relative levels of hsa-miR-101-5p and hsa-miR-101-3p showed significant positive correlations in both groups of patients. Statistically significant correlation was observed between hsa-miR-101 (-3p and -5p) and hsa-miR-29c-3p only in the obstructed group. The significant downregulation of anti-fibrotic hsa-miR-29c-3p in obstructive CAKUT could explain activation of genes involved in fibrotic processes. As miRNAs are promising candidates in therapeutic approaches our results need further measurement of fibrotic markers or assessment of extent of fibrosis and functional evaluation of hsa-miR-29c.

Crosstalk between miRNAs and DNA Methylation in Cancer

miRNAs are some of the most well-characterized regulators of gene expression. Integral to several physiological processes, their aberrant expression often drives the pathogenesis of both benign and malignant diseases. Similarly, DNA methylation represents an epigenetic modification influencing transcription and playing a critical role in silencing numerous genes. The silencing of tumor suppressor genes through DNA methylation has been reported in many types of cancer and is associated with tumor development and progression. A growing body of literature has described the crosstalk between DNA methylation and miRNAs as an additional layer in the regulation of gene expression. Methylation in miRNA promoter regions inhibits its transcription, while miRNAs can target transcripts and subsequently regulate the proteins responsible for DNA methylation. Such relationships between miRNA and DNA methylation serve an important regulatory role in several tumor types and highlight a novel avenue for potential therapeutic targets. In this review, we discuss the crosstalk between DNA methylation and miRNA expression in the pathogenesis of cancer and describe how miRNAs influence DNA methylation and, conversely, how methylation impacts the expression of miRNAs. Finally, we address how these epigenetic modifications may be leveraged as biomarkers in cancer.

MiR-29c-3p represses gastric cancer development via modulating MEST

Gastric cancer (GC) triggers a great number of deaths worldwide. Although great efforts have been made in treating this cancer, GC patients' survival rate remains unsatisfactory. An increasing amount of evidence indicates that miR-29c-3p inhibits cancer progression. However, the mechanism of miR-29c-3p in GC remains to be fully defined. Hence, this work aimed to analyze the underlying mechanism of miR-29c-3p in GC. Outcomes showed marked downregulation of miR-29c-3p in GC tissue and cell lines. Functional experiments exhibited that miR-29c-3p repressed GC cell malignant behaviors. Moreover, bioinformatics analysis and dual-luciferase reporter gene detection indicated that MEST was targeted by miR-29c-3p. Rescue assay further proved that MEST participated in functions of miR-29c-3p in GC. To sum up, miR-29c-3p/MEST signaling pathway suppressed formation of malignant phenotypes of GC, and targeting the signaling pathway may be a new method for treating GC.

Epi-miRNAs: Modern mediators of methylation status in human cancers

Methylation of the fundamental macromolecules, DNA/RNA, and proteins, is remarkably abundant, evolutionarily conserved, and functionally significant in cellular homeostasis and normal tissue/organism development. Disrupted methylation imprinting is strongly linked to loss of the physiological equilibrium and numerous human pathologies, and most importantly to carcinogenesis, tumor heterogeneity, and cancer progression. Mounting recent evidence has documented the active implication of miRNAs in the orchestration of the multicomponent cellular methylation machineries and the deregulation of methylation profile in the epigenetic, epitranscriptomic, and epiproteomic levels during cancer onset and progression. The elucidation of such regulatory networks between the miRNome and the cellular methylation machineries has led to the emergence of a novel subclass of miRNAs, namely "epi-miRNAs" or "epi-miRs." Herein, we have summarized the existing knowledge on the functional role of epi-miRs in the methylation dynamic landscape of human cancers and their clinical utility in modern cancer diagnostics and tailored therapeutics. This article is categorized under: RNA in Disease and Development > RNA in Disease.

Non-Coding RNA-Dependent Regulation of Mitochondrial Dynamics in Cancer Pathophysiology

Mitochondria are essential organelles which dynamically change their shape and number to adapt to various environmental signals in diverse physio-pathological contexts. Mitochondrial dynamics refers to the delicate balance between mitochondrial fission (or fragmentation) and fusion, that plays a pivotal role in maintaining mitochondrial homeostasis and quality control, impinging on other mitochondrial processes such as metabolism, apoptosis, mitophagy, and autophagy. In this review, we will discuss how dysregulated mitochondrial dynamics can affect different cancer hallmarks, significantly impacting tumor growth, survival, invasion, and chemoresistance. Special emphasis will be given to emerging non-coding RNA molecules targeting the main fusion/fission effectors, acting as novel relevant upstream regulators of the mitochondrial dynamics rheostat in a wide range of tumors.

pH-responsive nanoparticles based on POEOMA-b-PDPA block copolymers for RNA encapsulation, protection and cell delivery

The use of gene-based products, such as DNA or RNA, is increasingly being explored for various innovative therapies. However, the success of these strategies is highly dependent on the effective delivery of these biomolecules to target cells. Therefore, the development of pH-responsive nanoparticles comprises the creation of intelligent delivery systems with high therapeutic efficiency. In this work, the pH-responsiveness of the poly(2-(diisopropylamino)ethyl methacrylate)) (PDPA) block was investigated for the encapsulation and delivery of small RNAs (sRNA) to cancer cells. The pH responsiveness was dependent on the protonation profile of the tertiary amines of PDPA, which directly affected the electrostatic interactions established with RNA. Thus, block copolymers based on poly(oligo(ethylene oxide) methyl ether methacrylate) (POEOMA) and PDPA, POEOMA-b-PDPA, were synthesized by supplemental activator and reducing agent atom transfer radical polymerization (SARA ATRP). The structure of the block copolymers was characterized by size exclusion chromatography and ¹H NMR spectroscopy. The copolymers allowed effective complexation of model sRNAs and a pre-miRNA with efficiencies of about 89 % and 91 %, respectively. The characterization by dynamic light scattering revealed that these systems had sizes between 76 and 1375 nm. It was also found that the morphology of the polyplexes depended on the pH, since the preparation at a pH lower than the pKa of the copolymers resulted in spherical but polydisperse particles, while higher pH values resulted in nanoparticles with more homogeneous size, but altered morphology. Moreover, due to pH-responsiveness, it was achieved the release of RNA at pH higher than the pKa of the copolymers, while maintaining its integrity. The polyplexes also showed a high potential to protect RNA from RNases. The transfection of a lung cancer model (A549) and fibroblast cell lines showed that these polyplexes did not cause cell toxicity. In addition, the polyplexes enabled the effective transfection of the A549 cell line with pre-miRNA-29b and miRNA-29b, resulting in a decrease of expression levels of the target DNMT3B gene by approximately 51 % and 47 %, respectively. Overall, the POEOMA-b-PDPA copolymers proved to be a promising strategy for developing responsive delivery systems, that can play a critical role in some diseases, such as cancer, where pH varies between the intra and extracellular environments.

DNMT3B overexpression downregulates genes with CpG islands, common motifs, and transcription factor binding sites that interact with DNMT3B

DNA methylation is a key epigenetic modification to regulate gene expression in mammalian cells. Abnormal DNA methylation in gene promoters is common across human cancer types. DNMT3B is the main de novo methyltransferase enhanced in several primary tumors. How de novo methylation is established in genes related to cancer is poorly understood. CpG islands (CGIs), common sequences, and transcription factors (TFs) that interact with DNMT3B have been associated with abnormal de novo methylation. We initially identified cis elements associated with DNA methylation to investigate the contribution of DNMT3B overexpression to the deregulation of its possible target genes in an epithelial cell model. In a set of downregulated genes (n = 146) from HaCaT cells with DNMT3B overexpression, we found CGI, common sequences, and TFs Binding Sites that interact with DNMT3B (we called them P-down-3B). PPL1, VAV3, IRF1, and BRAF are P-down-3B genes that are downregulated and increased their methylation in DNMT3B presence. Together these findings suggest that methylated promoters aberrantly have some cis elements that could conduce de novo methylation by DNMT3B.

Integrative analyses of prognosis, tumor immunity, and ceRNA network of the ferroptosis-associated gene FANCD2 in hepatocellular carcinoma

Extensive evidence has revealed that ferroptosis plays a vital role in HCC development and progression. Fanconi anemia complementation group D2 (FANCD2) has been reported to serve as a ferroptosis-associated gene and has a close relationship with tumorigenesis and drug resistance. However, the impact of the FANCD2-related immune response and its mechanisms in HCC remains incompletely understood. In the current research, we evaluated the prognostic significance and immune-associated mechanism of FANCD2 based on multiple bioinformatics methods and databases. The results demonstrated that FANCD2 was commonly upregulated in 15/33 tumors, and only the high expression of FANCD2 in HCC was closely correlated with worse clinical outcomes by OS and DFS analyses. Moreover, ncRNAs, including two major types, miRNAs and lncRNAs, were closely involved in mediating FANCD2 upregulation in HCC and were established in a ceRNA network by performing various in silico analyses. The DUXAP8-miR-29c-FANCD2 and LINC00511-miR-29c-FANCD2 axes were identified as the most likely ncRNA-associated upstream regulatory axis of FANCD2 in HCC. Finally, FANCD2 expression was confirmed to be positively related to HCC immune cell infiltration, immune checkpoints, and IPS analysis, and GSEA results also revealed that this ferroptosis-associated gene was primarily involved in cancer-associated pathways in HCC. In conclusion, our investigations indicate that ncRNA-related modulatory overexpression of FANCD2 might act as a promising prognostic and immunotherapeutic target against HCC.

MicroRNA-mediated regulation of key signaling pathways in hepatocellular carcinoma: A mechanistic insight

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer. The molecular pathogenesis of HCC varies due to the different etiologies and genotoxic insults. The development of HCC is characterized by complex interactions between several etiological factors that result in genetic and epigenetic changes in proto-onco and/or tumor suppressor genes. MicroRNAs (miRNAs) are short non-coding RNAs that also can act as oncomiRs or tumor suppressors regulating the expression of cancer-associated genes post-transcriptionally. Studies revealed that several microRNAs are directly or indirectly involved in cellular signaling, and dysregulation of those miRNAs in the body fluids or tissues potentially affects key signaling pathways resulting in carcinogenesis. Therefore, in this mini-review, we discussed recent progress in microRNA-mediated regulation of crucial signaling networks during HCC development, concentrating on the most relevant ones such as PI3K/Akt/mTOR, Hippo-YAP/TAZ, and Wnt/β-catenin, which might open new avenues in HCC management.

The Role of miR-29s in Human Cancers—An Update

MicroRNAs (miRNAs) are small non-coding RNAs that directly bind to the 3’ untranslated region (3’-UTR) of the target mRNAs to inhibit their expression. The miRNA-29s (miR-29s) are suggested to be either tumor suppressors or oncogenic miRNAs that are strongly dysregulated in various types of cancer. Their dysregulation alters the expression of their target genes, thereby exerting influence on different cellular pathways including cell proliferation, apoptosis, migration, and invasion, thereby contributing to carcinogenesis. In the present review, we aimed to provide an overview of the current knowledge on the miR-29s biological network and its functions in cancer, as well as its current and potential applications as a diagnostic and prognostic biomarker and/or a therapeutic target in major types of human cancer.

Advances in prognostic and therapeutic targets for hepatocellular carcinoma and intrahepatic cholangiocarcinoma: The hippo signaling pathway

Primary liver cancer is the sixth most frequently diagnosed cancer worldwide and the third leading cause of cancer-related death. The majority of the primary liver cancer cases are hepatocellular carcinoma and intrahepatic cholangiocarcinoma. Worldwide, there is an increasing incidence of primary liver cancer cases due to multiple risk factors ranging from parasites and viruses to metabolic diseases and lifestyles. Often, patients are diagnosed at advanced stages, depriving them of surgical curability benefits. Moreover, the efficacy of the available chemotherapeutics is limited in advanced stages. Furthermore, tumor metastases and recurrence make primary liver cancer management exceptionally challenging. Thus, exploring the molecular mechanisms for the development and progression of primary liver cancer is critical in improving diagnostic, treatment, prognostication, and surveillance modalities. These mechanisms facilitate the discovery of specific targets that are critical for novel and more efficient treatments. Consequently, the Hippo signaling pathway executing a pivotal role in organogenesis, hemostasis, and regeneration of tissues, regulates liver cells proliferation, and apoptosis. Cell polarity or adhesion molecules and cellular metabolic status are some of the biological activators of the pathway. Thus, understanding the mechanisms exhibited by the Hippo pathway is critical to the development of novel targeted therapies. This study reviews the advances in identifying therapeutic targets and prognostic markers of the Hippo pathway for primary liver cancer in the past six years.

Cross-regulation between microRNAs and key proteins of signaling pathways in hepatocellular carcinoma

INTRODUCTION

Hepatocellular carcinoma (HCC) is a subtype of primary liver cancer and a major cause of death. Although miRNA plays an important role in hepatocellular carcinoma, the specific regulatory network remains unclear. Therefore, this paper comprehensively describes the miRNA-related signaling pathways in HCC and the possible interactions among different signaling pathways. The aim is to lay the foundation for the discovery of new molecular targets and multi-target therapy.

AREAS COVERED

Based on miRNA, HCC, and signaling pathways, the literature was searched on Web of Science and PubMed. Then, common targets between different signaling pathways were found from KEGG database, and possible cross-regulation mechanisms were further studied. In this review, we elaborated from two aspects, respectively, laying a foundation for studying the regulatory mechanism and potential targets of miRNA in HCC.

EXPERT OPINION

Non-coding RNAs have become notable molecules in cancer research in recent years, and many types of targeted drugs have emerged. From the outset, molecular targets and signal pathways are interlinked, which suggests that signal pathways and regulatory networks should be concerned in basic research, which also provides a strong direction for future mechanism research.

MiR-27a-3p binds to TET1 mediated DNA demethylation of ADCY6 regulates breast cancer progression via epithelial-mesenchymal transition

Introduction

Adenylyl cyclase isoform 6 (ADCY6) is a member of membrane-bound adenylate cyclase family that converts adenosine triphosphate (ATP) into cAMP and pyrophosphate. An increasing number of researchers have studied the role of ADCY6 in cancer. However, its specific role in breast cancer remains unknown.

Methods

Bioinformatics and clinical data were used to analyse the expression of ADCY6 in breast cancer. ADCY6 DNA methylation was analysed using DNA methylation-specific PCR and Bisulfite Sanger sequencing. Using lentiviral stable miRNA transfection together with cell biology functional assays and gene expression/target analysis, we investigated the interaction between miR-27a-3p, TET1 and ADCY6 in breast cancer.

Results

We found that ADCY6 is expressed at low levels in breast cancer and leads to increases in the proliferation, invasion and migration of breast cancer cells. The low expression of ADCY6 is due to the lower demethylation of ten-eleven translocation methylcytosine dioxygenase 1 (TET1), and the methylation of ADCY6 can be altered by TET1. More importantly, bioinformatics analysis showed that TET1 is regulated by miR-27a-3p and regulates the methylation of ADCY6 to affect the EMT process of breast cancer cells, thereby affecting the malignant biological behaviour of breast cancer.

Conclusions

Our study demonstrates that the methylation modification of ADCY6 is regulated by TET1 and leads to ADCY6 activation. miR-27a-3p negatively regulates the expression of TET1 and affects the EMT process of breast cancer through ADCY6, thereby promoting the malignant biological behaviour of breast cancer. Our results may provide new research ideas and directions for DNA methylation and EMT changes in breast cancer.

miR-203a-3p-DNMT3B feedback loop facilitates non-small cell lung cancer progression

It has been reported that microRNA-203a-3p (miR-203a-3p) modulates cell proliferation, migration and invasion in a variety of cancer cell types. However, little is known about its role in lung cancer progression. The present study found that miR-203a-3p was downregulated in non-small cell lung cancer (NSCLC) cell lines and tissues. Overexpression of miR-203a-3p inhibits NSCLC cell proliferation, migration and invasion, and promotes cellular apoptosis in vitro. Restoration of miR-203a-3p expression in A549 and NCI-H520 cells enhances their chemosensitivity. Further experiments showed that DNA methyltransferase 3B (DNMT3B) was a direct target of miR-203a-3p. In addition, the present results revealed that promoter hypermethylation was the potential mechanism responsible for low miR-203a-3p expression in NSCLC. Notably, feedback regulation between miR-203a-3p and DNMT3B was observed in NSCLC. Moreover, Overexpression of miR-203a-3p reduces tumor growth in vivo. In summary, the present study has identified an miR-203a-3p-DNMT3B feedback loop that facilitates NSCLC progression.

Exosomal miRNA Profile in Small-for-Gestational-Age Children: A Potential Biomarker for Catch-Up Growth

Objective: The mechanism underlying postnatal growth failure and catch-up growth in small-for-gestational-age (SGA) children is poorly understood. This study investigated the exosomal miRNA signature associated with catch-up growth in SGA children. Methods: In total, 16 SGA and 10 appropriate-for-gestational-age (AGA) children were included. Serum exosomal miRNA was analyzed using next-generation sequencing (NGS). Exosomal miRNA was profiled for five SGA children with catch-up growth (SGA-CU), six SGA children without CU growth (SGA-nCU), and five AGA children. Results: Exosomal miRNA profiles were clustered into three clear groups. The exosomal miRNA expression profiles of the SGA-nCU group differed from those of the SGA-CU and AGA groups. In all, 22 miRNAs were differentially expressed between SGA-nCU and AGA, 19 between SGA-nCU and SGA-CU, and only 6 between SGA-CU and AGA. In both SGA-nCU and SGA-CU, miR-874-3p was upregulated and miR-6126 was downregulated. Therefore, these two miRNAs could serve as biomarkers for SGA. Compared with SGA-CU and AGA, miR-30c-5p, miR-363-3p, miR-29a-3p, and miR-29c-3p were upregulated in SGA-nCU, while miR-629-5p and miR-23a-5p were downregulated. These six miRNAs could be associated with growth failure in SGA-nCU children. Conclusions: SGA children without CU have a distinct exosomal miRNA expression profile compared with AGA and SGA children with CU. Exosomal miRNAs could serve as novel biomarkers for CU.

COMMD2 Upregulation Mediated by an ncRNA Axis Correlates With an Unfavorable Prognosis and Tumor Immune Infiltration in Liver Hepatocellular Carcinoma

Liver hepatocellular carcinoma (LIHC) seriously endangers the health and quality of life of individuals worldwide. Increasing evidence has underscored that the copper metabolism MURR1 domain (COMMD) family plays important roles in tumorigenesis. However, the specific role, biological function, mechanism and prognostic value of COMMD2 and its correlation with immune cell infiltration in LIHC remain unknown. In this study, we first determined the expression and prognostic potential of COMMD2 in human tumors using The Cancer Genome Atlas (TCGA) data and identified COMMD2 as a potential oncogene in LIHC. High COMMD2 expression was associated with pathological tumor stage and metastasis. Subsequently, noncoding RNAs (ncRNAs) upregulating COMMD2 expression were identified by performing expression, correlation, and survival analyses in combination. The CRNDE/LINC00511/SNHG17/HCG18-miR-29c-3p axis was identified as the most likely ncRNA-associated pathway upstream of COMMD2 in LIHC. Next, the expression profiles of COMMD2 and ncRNAs were validated in LIHC tissues and adjacent normal tissues. Furthermore, COMMD2 was significantly positively correlated with tumor immune cell infiltration, immune cell biomarkers, and immune checkpoint molecule expression. Importantly, COMMD2 potentially influenced prognosis by regulating immune cell infiltration in LIHC. Finally, COMMD2 was knocked down in LIHC cell lines using siRNAs for functional assays in vitro, resulting in suppressed cell proliferation and migration. In summary, our findings showed that the ncRNA-mediated upregulation of COMMD2 was associated with an unfavorable prognosis correlated with immune cell infiltration in LIHC.

Epigenetic changes induced in mice liver by methionine-supplemented and methionine-deficient diets

A diet deficient in donors of methyl group, such as methionine, affects DNA methylation and hepatic lipid metabolism. Methionine also affects other epigenetic mechanisms, such as microRNAs. We investigated the effects of methionine-supplemented or methionine-deficient diets on the expression of chromatin-modifying genes, global DNA methylation, the expression and methylation of genes related to lipid metabolism, and the expression of microRNAs in mouse liver. Female Swiss albino mice were fed a control diet (0.3% methionine), a methionine-supplemented diet (2% methionine), and a methionine-deficient diet (0% methionine) for 10 weeks. The genes most affected by the methionine-supplemented diet were associated with histone and DNA methyltransferases activity, while the methionine-deficient diet mostly altered the expression of histone methyltransferases genes. Both diets altered the global DNA methylation and the expression and gene-specific methylation of the lipid metabolism gene Apoa5. Both diets altered the expression of several liver homeostasis-related microRNAs, including miR-190b-5p, miR-130b-3p, miR-376c-3p, miR-411-5p, miR-29c-3p, miR-295-3p, and miR-467d-5p, with the methionine-deficient diet causing a more substantial effect. The effects of improper amounts of methionine in the diet on liver pathologies may involve a cooperative action of chromatin-modifying genes, which results in an aberrant pattern of global and gene-specific methylation, and microRNAs responsible for liver homeostasis.

Potential plasma biomarkers: miRNA-29c, miRNA-21, and miRNA-155 in clinical progression of Hepatocellular Carcinoma patients

This study evaluated differences in the clinical appearance of patients with hepatocellular carcinoma (HCC) based on plasma level and regulation of microRNAs (miRNA-29c, miRNA-21, and miRNA-155). The observational-analytical study with a cross-sectional design was conducted on 36 HCC patients and 36 healthy controls. The blood samples were collected from 2 Province Hospitals (Dr. Sardjito Hospital and Prof. Dr. Margono Soekarjo Hospital) for HCC and the Blood Bank Donor of the Indonesian Red Cross for 36 healthy controls. These blood samples were treated as follows: plasma isolation, RNA isolation, cDNA synthesis, quantification by qRT-PCR using a sequence-specific forward primer, and normalization of miRNA using housekeeping-stably miRNA-16. There were only 27 HCC patients with complete clinical variables (neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), platelet count, albumin, C-reactive protein (CRP), and cholinesterase (ChE)) that were able to analyses for regulation miRNAs based on its fold change expression miRNA target. All 27 HCC subjects were follow-up until 3-years of monitoring for their overall survival. The miRNA plasma expression was analyzed by Bio-Rad CFX 96 Manager software to determine the cycle of quantification, followed by the calculation of expression levels using Livak's methods. Data were analyzed using STATA 11.0, with a significant value of p<0.05. The miRNAs expression of HCC subjects were lower than that healthy control subjects in miRNA-29c (down-regulation 1.83-fold), higher than that healthy control subjects in miRNA 21 and miRNA-155 (up-regulation, 1.74-fold; 1.55-fold) respectively. NLR, CRP, ChE, and platelet count showed a significant difference in miRNA-29c regulation, though neutrophil count showed a significant difference in miRNA-21 and miRNA-155 regulation (p<0.05). Conclusion: Plasma biomarkers: miRNA-21 and miRNA-155 might be potential biomarkers as onco-miR in HCC subjects, while miRNA-29c might act as a tumor suppressor. Significant evidence was identified with clinical progression based on the regulation of miRNAs, which was consistent with miRNA -29c.

MiR-29c-3p May Promote the Progression of Alzheimer's Disease through BACE1

The aim of this study was to explore the specific role of miR-29c-3p in Alzheimer's disease (AD). Animal models of AD were established by injecting streptozotocin (STZ) into mice through the lateral ventricle, while cell models of AD were induced by 10 μM β-amyloid (Aβ). We detected miR-29c-3p and β-site amyloid precursor protein cleaving enzyme 1 (BACE1) contents and measured AD cell proliferation and apoptosis. A low miR-29c-3p level and a high BACE1 level were detected in the brain tissue of AD animal models and AD cell models. Aβ-processed cells had markedly lower proliferation activity, higher apoptosis, increased phosphorylation of tau protein was over phosphorylated, but the overexpression of miR-29c-3p or the silencing of BACE1 significantly enhanced the cell proliferation activity and reduced cell apoptosis by regulating the contents of related proteins. Inhibition of miR-29c-3p or overexpression of BACE1 aggravated Aβ-induced side effects. We used Targetscan7.2 to predict the downstream target genes of miR-29c-3p. Then, we detected that there were target binding sites between miR-29c-3p and BACE1. The rescue experiment identified BACE1 as a functional target for miR-29c-3p. AD leads to decreased miR-29c-3p level and increased BACE1 level. MiR-29c-3p has specific binding sites with the 3′-untranslated region (3′-UTR) of BACE1 and thus negatively regulates the BACE1 level, thereby affecting the progression of AD.

Role of miR-653 and miR-29c in downregulation of CYP1A2 expression in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is a major contributor to the worldwide cancer burden. Recent studies on HCC have demonstrated dramatic alterations in expression of several cytochrome P450 (CYP) family members that play a crucial role in biotransformation of many drugs and other xenobiotics; however, the mechanisms responsible for their deregulation remain unclear.

METHODS

We investigated a potential involvement of miRNAs in downregulation of expression of CYPs observed in HCC tumors. We compared miRNA expression profiles (TaqMan Array Human MicroRNA v3.0 TLDA qPCR) between HCC human patient tumors with strong (CYP-) and weak/no (CYP+) downregulation of drug-metabolizing CYPs. The role of significantly deregulated miRNAs in modulation of expression of the CYPs and associated xenobiotic receptors was then investigated in human liver HepaRG cells transfected with relevant miRNA mimics or inhibitors.

RESULTS

We identified five differentially expressed miRNAs in CYP- versus CYP+ tumors, namely miR-29c, miR-125b1, miR-505, miR-653 and miR-675. The two most-upregulated miRNAs found in CYP- tumor samples, miR-29c and miR-653, were found to act as efficient suppressors of CYP1A2 or AHR expression.

CONCLUSIONS

Our results revealed a novel role of miR-653 and miR-29c in regulation of expresion of CYPs involved in crucial biotransformation processes in liver, which are often deregulated during liver cancer progression.

MicroRNA-199b-3p suppresses malignant proliferation by targeting Phospholipase Cε and correlated with poor prognosis in prostate cancer

OBJECTIVES

MicroRNA-199b-3p (miR-199b-3p) plays a crucial role in the malignant development of various cancers, but little known in prostate cancer (PCa). The aim of our study was to demonstrate the function of miR-199b-3p in PCa.

METHODS

Quantitative real-time polymerase chain reaction (RT-qPCR) was used to detect miR-199b-3p expression in PCa and benign prostatic hyperplasia (BPH) tissue samples. In addition, we examined the relationship between the poor prognosis in PCa and miR-199b-3p. Western blot was used to analyze the expression of Phospholipase Cε (PLCε). CCK8 and colony-forming assays were applied to detect the proliferation of PCa. EdU assay is used to detect PCa cells uptake of EdU. Luciferase reporter assay was applied to analyze the binding between miR-199b-3p and PLCε.

RESULTS

It has been shown that miR-199b-3p in PCa was significantly lower than that in benign prostatic hyperplasia and correlated with poor prognosis. Meanwhile, upregulation of miR-199b-3p can prominently inhibit the proliferation of PCa cells, while its down-regulation triggered opposite result. PLCε was identified as the downstream binding target gene and negatively associated with that of miR-199b-3p.

CONCLUSION

miR-199b-3p suppresses malignant proliferation by inhibiting PLCε in prostate cancer in vitro and vivo.

Knockdown of long noncoding RNA colorectal neoplasia differentially expressed inhibits hepatocellular carcinoma progression by mediating the expression of nuclear autoantigenic sperm protein

Long noncoding RNAs (lncRNAs) play critical roles in the tumorigenesis and progression of hepatocellular carcinoma (HCC). As the most common malignant cancer type in humans, HCC poses a great threat to human health. However, the function of lncRNA colorectal neoplasia differentially expressed (CRNDE) in HCC has not been extensively studied. The chief aim of the present study was to reveal the potential role of CRNDE in HCC. Expression levels of CRNDE in HCC tissues and cell lines were detected by reverse transcription‑quantitative (RT‑q) PCR, and Cell Counting kit 8, wound‑healing and Transwell assays were used to evaluate the influences of CRNDE on in vitro cellular proliferation, migration and invasiveness, respectively. The interaction between CRNDE and microRNA (miR)‑29c‑3p was determined by dual‑luciferase reporter assay, and rescue experiments were conducted to evaluate the interactive relationships between CRNDE and miR‑29c‑3p or nuclear autoantigenic sperm protein (NASP). CRNDE was found to be upregulated in HCC tissues and cells, and to be positively associated with the poor prognosis of patients with HCC. Furthermore, CRNDE‑knockdown suppressed cell proliferation, migration and invasion abilities. Bioinformatics and RT‑qPCR analysis indicated miR‑29c‑3p as a potential target of CRNDE. In line with previous reports, as a tumor suppressor, downregulated expression of miR‑29c‑3p was observed in HCC. In addition, the present study revealed that miR‑29c‑3p directly targeted NASP. NASP expression was markedly elevated following transfection with an miR‑29c‑3p inhibitor, while knocking down CRNDE inhibited NASP expression. Moreover, the effects of CRNDE and NASP on HCC cells were reversed by miR‑29c‑3p. Collectively, the results of the present study revealed that CRNDE was upregulated and exerted an oncogenic role in HCC by targeting miR‑29c‑3p, and that the upregulation of CRNDE also promoted NASP expression. These findings indicate a novel role for CRNDE in the progression of HCC.

A construction and comprehensive analysis of ceRNA networks and infiltrating immune cells in papillary renal cell carcinoma

Background

As the second most common malignancy in adults, papillary renal cell carcinoma (PRCC) has shown an increasing trend in both incidence and mortality. Effective treatment for advanced metastatic PRCC is still lacking. In this study, we aimed to establish competitive endogenous RNA (ceRNA) networks related to PRCC tumorigenesis, and analyze the specific role of differentially expressed ceRNA components and infiltrating immune cells in tumorigenesis.

Methods

CeRNA networks were established to identify the key ceRNAs related to PRCC tumorigenesis based on the 318 samples from The Cancer Genome Atlas database (TCGA), including 285 PRCC and 33 normal control samples. The R package, “CIBERSORT,” was used to evaluate the infiltration of 22 types of immune cells. Then we identified the significant ceRNAs and immune cells, based on which two nomograms were obtained for predicting the prognosis in PRCC patients. Finally, we investigated the co‐expression of PRCC‐specific immune cells and core ceRNAs via Pearson correlation test.

Results

COL1A1, H19, ITPKB, LDLR, TCF4, and WNK3 were identified as hub genes in ceRNA networks. Four prognostic‐related tumor‐infiltrating immune cells, including T cells CD4 memory resting, Macrophages M1, and Macrophages M2 were revealed. Pearson correlation test indicated that Macrophage M1 was negatively related with COL1A1 (p < 0.01) and LDLR (p < 0.01), while Macrophage M2 was positively related with COL1A1 (p < 0.01), TCF4 (p < 0.01), and H19 (p = 0.032). Two nomograms were conducted with favorable accuracies (area under curve of 1‐year survival: 0.935 and 0.877; 3‐year survival: 0.849 and 0.841; and 5‐year survival: 0.818 and 0.775, respectively).

Conclusion

The study constructed two nomograms suited for PRCC prognosis predicting. Moreover, we concluded that H19‐miR‐29c‐3p‐COL1A1 axis might promote the polarization of M2 macrophages and inhibit M1 macrophage activation through Wnt signaling pathway, collaborating to promote PRCC tumorigenesis and lead to poor overall survival of PRCC patients.

Integrative Analysis of DNA Methylation and microRNA Expression Reveals Mechanisms of Racial Heterogeneity in Hepatocellular Carcinoma

Pathologic alterations in epigenetic regulation have long been considered a hallmark of many cancers, including hepatocellular carcinoma (HCC). In a healthy individual, the relationship between DNA methylation and microRNA (miRNA) expression maintains a fine balance; however, disruptions in this harmony can aid in the genesis of cancer or the propagation of existing cancers. The balance between DNA methylation and microRNA expression and its potential disturbance in HCC can vary by race. There is emerging evidence linking epigenetic events including DNA methylation and miRNA expression to cancer disparities. In this paper, we evaluate the epigenetic mechanisms of racial heterogenity in HCC through an integrated analysis of DNA methylation, miRNA, and combined regulation of gene expression. Specifically, we generated DNA methylation, mRNA-seq, and miRNA-seq data through the analysis of tumor and adjacent non-tumor liver tissues from African Americans (AA) and European Americans (EA) with HCC. Using mixed ANOVA, we identified cytosine-phosphate-guanine (CpG) sites, mRNAs, and miRNAs that are significantly altered in HCC vs. adjacent non-tumor tissue in a race-specific manner. We observed that the methylome was drastically changed in EA with a significantly larger number of differentially methylated and differentially expressed genes than in AA. On the other hand, the miRNA expression was altered to a larger extent in AA than in EA. Pathway analysis functionally linked epigenetic regulation in EA to processes involved in immune cell maturation, inflammation, and vascular remodeling. In contrast, cellular proliferation, metabolism, and growth pathways are found to predominate in AA as a result of this epigenetic analysis. Furthermore, through integrative analysis, we identified significantly differentially expressed genes in HCC with disparate epigenetic regulation, associated with changes in miRNA expression for AA and DNA methylation for EA.

Shikonin ameliorates injury and inflammatory response of LPS-stimulated WI-38 cells via modulating the miR-489-3p/MAP2K1 axis

Pneumonia is an inflammatory disease induced by infection with different pathogens. Currently, multiple preclinical studies have revealed that shikonin, a natural naphthoquinone, can mitigate lipopolysaccharide (LPS)-induced inflammation, but its underlying mechanism in pneumonia remains unknown. This research was designed to explore the function and regulatory mechanism of shikonin in LPS-induced cell injury and inflammation in WI-38 cells. In-vitro model of pneumonia was constructed by treating WI-38 cells with LPS. Expression of miR-489-3p and MAP2K1 was tested by RT-qPCR and (or) Western blot analysis. Cell viability was examined by 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide assay. The productions of pro-inflammatory cytokines were determined by enzyme-linked immunosorbent assays. Cell apoptosis was detected by Western blot and flow cytometry analysis. In the current study, LPS induced WI-38 cell damage by inhibiting cell viability and promoting cell apoptosis and inflammation. Shikonin ameliorated LPS-induced cell injury and elevated miR-489-3p expression. LPS-induced inflammatory injury was further mitigated by upregulation of miR-489-3p. In addition, MAP2K1, the target of miR-489-3p, was upregulated by LPS. Furthermore, upregulation of MAP2K1 reversed the influence of shikonin and miR-489-3p mimics on LPS-induced cell injury and inflammation. This study revealed that shikonin protected WI-38 cells against LPS-induced cell injury and inflammatory response by regulating the miR-489-3p/MAP2K1 axis, thus affecting the progression of pneumonia.

Genome-wide analysis of DNA methylation identifies the apoptosis-related gene UQCRH as a tumor suppressor in renal cancer

DNA hypermethylation is frequently observed in clear cell renal cell carcinoma (ccRCC) and correlates with poor clinical outcomes. However, the detailed function of DNA hypermethylation in ccRCC has not been fully uncovered. Here, we show the role of DNA methylation in ccRCC progression through the identification of a target(s) of DNA methyltransferases (DNMT). Our preclinical model of ccRCC using the serial orthotopic inoculation model showed the upregulation of DNMT3B in advanced ccRCC. Pretreatment of advanced ccRCC cells with 5-aza-deoxycytidine, a DNMT inhibitor, attenuated the formation of primary tumors through the induction of apoptosis. DNA methylated sites were analyzed genome-wide using methylation array in reference to RNA-sequencing data. The gene encoding ubiquinol cytochrome c reductase hinge protein (UQCRH), one of the components of mitochondrial complex III, was extracted as a methylation target in advanced ccRCC. Immunohistochemical analysis revealed that the expression of UQCRH in human ccRCC tissues was lower than normal adjacent tissues. Silencing of UQCRH attenuated the cytochrome c release in response to apoptotic stimuli and resulted in enhancement of primary tumor formation in vivo, implying the tumor-suppressive role of UQCRH. Moreover, 5-aza-deoxycytidine enhanced the therapeutic efficiency of mammalian target of rapamycin inhibitor everolimus in vivo. These findings suggested that the DNMT3B-induced methylation of UQCRH may contribute to renal cancer progression and implicated clinical significance of DNMT inhibitor as a therapeutic option for ccRCC.

MiR-103a promotes tumour growth and influences glucose metabolism in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a common and high-mortality cancer worldwide. Numerous microRNAs have crucial roles in the progression of different cancers. However, identifying the important microRNAs and the target biological function of the microRNA in HCC progression is difficult. In this study, we selected highly expressed microRNAs with different read counts as candidate microRNAs and then tested whether the microRNAs were differentially expressed in HCC tumour tissues, and we found that their expression was related to the HCC prognosis. Then, we investigated the effects of microRNAs on the cell growth and mobility of HCC using a real-time cell analyser (RTCA), colony formation assay and subcutaneous xenograft models. We further used deep-sequencing technology and bioinformatic analyses to evaluate the main functions of the microRNAs. We found that miR-103a was one of the most highly expressed microRNAs in HCC tissues and that it was upregulated in HCC tissue compared with the controls. In addition, high miR-103a expression was associated with poor patient prognosis, and its overexpression promoted HCC cell growth and mobility. A functional enrichment analysis showed that miR-103a mainly promoted glucose metabolism and inhibited cell death. We validated this analysis, and the data showed that miR-103a promoted glucose metabolism-likely function and directly inhibited cell death via ATP11A and EIF5. Therefore, our study revealed that miR-103a may act as a key mediator in HCC progression.

Down-regulation of microRNA-125b-2-3p is a risk factor for a poor prognosis in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a leading cause of mortality in cancer patients, but the association between miR-125b-2-3p and the onset and prognosis of HCC has not been reported in previous studies; thus, the clinicopathological implications of miR-125b-2-3p in HCC require elaboration. To examine the expression of miR-125b-2-3p in HCC, both in-house RT-qPCR and public datasets were used to calculate the standard mean difference (SMD) and the summary receiver operating characteristic (sROC). MiR-125b-2-3p was markedly lower in HCC than in non-tumor tissue as assessed by the in-house RT-qPCR which was confirmed by the integrative analysis showing the SMD being -0.69 and the area under the curve (AUC) being 0.84 based on 1,233 cases of HCC and 630 cases of non-HCC controls. To gain a overview of the clinical value of miR-125b-2-3p in HCC, all possible datasets were integrated, and lower miR-125b-2-3p levels could lead to poorer differentiation and a more advanced clinical stage of HCC. The hazard ratio (HR) of miR-125b-2-3p was also calculated using a Cox proportional hazards model, and the miR-125b-2-3p level could act as an protective indication for the survival with the HR being 0.74 based on 586 cases of HCC. Furthermore, the effect of nitidine chloride (NC), a natural bioactive phytochemical alkaloid, on the regulation of miR-125b-2-3p and its potential targets was also investigated. The miR-125b-2-3p level was increased after NC treatment, while the expression of its potential target PRKCA was reduced. Above all, a low-expressed level of miR-125b-2-3p plays a tumor suppressive role in HCC.

The Epigenetic Modulation of Cancer and Immune Pathways in Hepatitis B Virus-Associated Hepatocellular Carcinoma: The Influence of HBx and miRNA Dysregulation

Hepatitis B virus (HBV)-associated hepatocellular carcinoma (HBV-HCC) pathogenesis is fueled by persistent HBV infection that stealthily maintains a delicate balance between viral replication and evasion of the host immune system. HBV is remarkably adept at using a combination of both its own, as well as host machinery to ensure its own replication and survival. A key tool in its arsenal, is the HBx protein which can manipulate the epigenetic landscape to decrease its own viral load and enhance persistence, as well as manage host genome epigenetic responses to the presence of viral infection. The HBx protein can initiate epigenetic modifications to dysregulate miRNA expression which, in turn, can regulate downstream epigenetic changes in HBV-HCC pathogenesis. We attempt to link the HBx and miRNA induced epigenetic modulations that influence both the HBV and host genome expression in HBV-HCC pathogenesis. In particular, the review investigates the interplay between CHB infection, the silencing role of miRNA, epigenetic change, immune system expression and HBV-HCC pathogenesis. The review demonstrates exactly how HBx-dysregulated miRNA in HBV-HCC pathogenesis influence and are influenced by epigenetic changes to modulate both viral and host genome expression. In particular, the review identifies a specific subset of HBx induced epigenetic miRNA pathways in HBV-HCC pathogenesis demonstrating the complex interplay between HBV infection, epigenetic change, disease and immune response. The wide-ranging influence of epigenetic change and miRNA modulation offers considerable potential as a therapeutic option in HBV-HCC.

CDC20 promotes the progression of hepatocellular carcinoma by regulating epithelial‑mesenchymal transition

Hepatocellular carcinoma (HCC) is a type of primary liver cancer, which is associated with high mortality. HCC is one of the most common malignant tumors worldwide. Cell division cycle 20 (CDC20) has been reported to be associated with the development of various malignant tumors and epithelial-mesenchymal transition (EMT) has been reported to be involved in the malignant metastasis of HCC. Therefore, the present study hypothesized that CDC20 may participate in the malignant biological behavior of HCC via EMT. The present study analyzed the expression levels of CDC20 in HCC and the association between CDC20 and poor prognosis. Furthermore, the effects of CDC20 on the proliferation, invasion and migration of HCC cells were examined using proliferation, migration and invasion assays. Finally, alterations in EMT were analyzed. The results revealed that CDC20 was highly expressed in HCC and HCC cell lines (P<0.05), and its high expression level was significantly associated with poor prognosis in patients with HCC (P<0.05). CDC20 silencing inhibited the proliferation, migration and invasion of HCC cells. Furthermore, CDC20 silencing increased the expression levels of E-cadherin, and decreased the expression levels of N-cadherin, vimentin and Ki-67. In conclusion, the present study reported that CDC20 may be a novel therapeutic target in HCC and CDC20 could promote the progression of HCC by regulating EMT.

PKM2 regulates proliferation and apoptosis through the Hippo pathway in oral tongue squamous cell carcinoma

Oral tongue squamous cell carcinoma (OTSCC) is a highly malignant type of tumor. The 5-year survival rate of patients with advanced tongue squamous cell carcinoma is only ~50%. Pyruvate kinase M2 (PKM2) is the key rate-limiting enzyme of glycolysis, maintaining the Warburg effect in tumor cells. The present study aimed to investigate the relationship between PKM2 expression and the poor prognosis of patients with OTSCC and to determine oral squamous carcinoma tumor cell proliferation and apoptosis. Reverse transcription-quantitative (RT-q) PCR, western blotting and immunohistochemistry were used to analyze the expression levels of PKM2 in OTSCC, and the clinicopathological characteristics and prognosis of patients with OTSCC were further analyzed by statistical analysis. The results from RT-qPCR and immunohistochemistry demonstrated that PKM2 was upregulated in OTSCC tissues and highly expressed in advanced stage OTSCC tissues compared with paired adjacent tissues and lower stage OTSCC tissues. Patients with OTSCC and high PKM2 expression had shorter overall survival (OS) compared with those with low PKM2 expression. Furthermore, high expression of PKM2 was significantly associated with Tumor-Node-Metastasis (TNM) stage. TNM stage and PKM2 expression were independent predictive factors for OS in patients with OTSCC. In addition, PKM2 knockdown inhibited the proliferation and increased the apoptosis of oral squamous carcinoma tumor cells. Furthermore, PKM2 knockdown could regulate the expression of cell cycle and apoptosis-related proteins by activating Hippo signaling pathway, as confirmed by the decreased expression of yes-associated protein 1 (YAP), Bcl-2 and Ki-67 and the increased expression of large tumor suppressor kinase 1, phosphorylated YAP and Bax. Taken together, the findings from this study demonstrated that PKM2 may be considered as a potential target for the diagnosis and treatment of OTSCC.

MicroRNAs Regulating Hippo-YAP Signaling in Liver Cancer

Liver cancer is one of the most common cancers worldwide, and its prevalence and mortality rate are increasing due to the lack of biomarkers and effective treatments. The Hippo signaling pathway has long been known to control liver size, and genetic depletion of Hippo kinases leads to liver cancer in mice through activation of the downstream effectors yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ). Both YAP and TAZ not only reprogram tumor cells but also alter the tumor microenvironment to exert carcinogenic effects. Therefore, understanding the mechanisms of YAP/TAZ-mediated liver tumorigenesis will help overcome liver cancer. For decades, small noncoding RNAs, microRNAs (miRNAs), have been reported to play critical roles in the pathogenesis of many cancers, including liver cancer. However, the interactions between miRNAs and Hippo-YAP/TAZ signaling in the liver are still largely unknown. Here, we review miRNAs that influence the proliferation, migration and apoptosis of tumor cells by modulating Hippo-YAP/TAZ signaling during hepatic tumorigenesis. Previous findings suggest that these miRNAs are potential biomarkers and therapeutic targets for the diagnosis, prognosis, and treatment of liver cancer.

MST1 inhibits the progression of breast cancer by regulating the Hippo signaling pathway and may serve as a prognostic biomarker

Breast cancer (BCa) is the most common malignancy threatening the health of women worldwide, and the incidence rate has significantly increased in the last 10 years. Mammalian STE20-like protein kinase 1 (MST1) is involved in the development of various types of malignant tumor. The present study aimed to investigate the role of MST1 in BCa and its potential involvement in the poor prognosis of patients with BCa. Reverse transcription-quantitative PCR and immunohistochemistry were used to analyze the expression levels of MST1 in BCa, and the clinicopathological characteristics and prognosis of patients with BCa were further analyzed by statistical analysis. MST1 was overexpressed in BCa cell lines (MCF-7, MDA-MB-231 and SKBR3). Cell Counting Kit-8, 5-ethynyl-2′-deoxyuridine and flow cytometry assays were used to analyze cell proliferation and apoptosis, respectively, and a wound healing assay was used to analyze cell migration. The results of the present study revealed that the downregulated expression levels of MST1 in BCa were closely associated with the poor prognosis of patients, and MST1 may be an independent risk factor for BCa. The overexpression of MST1 significantly inhibited the proliferation and migration, and promoted the apoptosis of BCa cells. In addition, the overexpression of MST1 significantly activated the Hippo signaling pathway. Treatment with XMU-MP-1 downregulated the expression levels of MST1 and partially reversed the inhibitory effects of MST1 on proliferation, migration and apoptosis-related proteins, and inhibited the Hippo signaling pathway. In conclusion, the results of the present study suggested that MST1 expression levels may be downregulated in BCa and closely associated with tumor size and clinical stage, as well as the poor prognosis of affected patients. Furthermore, MST1 may inhibit the progression of BCa by targeting the Hippo signaling pathway.

miR-29b restrains cholangiocarcinoma progression by relieving DNMT3B-mediated repression of CDKN2B expression

Numerous studies have reported the important role of microRNAs (miRNAs) in human cancers. Although abnormal miR-29b expression has been linked to tumorigenesis in several cancers, its role in cholangiocarcinoma remains largely unknown. We found that miR-29b expression is frequently downregulated in human cholangiocarcinoma QBC939 cells and in clinical tumor samples. In cholangiocarcinoma patients, low miR-29b expression predicts poor overall survival. Overexpression of miR-29b in QBC939 cells inhibited proliferation, induced G1 phase cycle arrest, and promoted apoptosis. Methylation-specific PCR (MSP) analysis revealed a decreased methylation imprint at the promoter of the cell cycle inhibitor gene CDKN2B in cells overexpressing miR-29b. After identifying the DNA methyltransferase DNMT3B as a putative miR-29b target, luciferase reporter assays confirmed a suppressive effect of miR-29b on DNMT3B expression. Accordingly, we detected an inverse correlation between miR-29b and DNMT3B expression in clinical cholangiocarcinoma specimens. In QBC939 cells, DNMT3B overexpression promoted proliferation and inhibited apoptosis. DNMT3B silencing, in turn, led to increased CDKN2B expression. We also observed significant growth arrest in subcutaneous tumors formed in nude mice by QBC939 cells overexpressing miR-29b. These findings suggest miR-29b functions as a tumor suppressor in cholangiocarcinoma by relieving DNMT3B-mediated repression of CDKN2B expression.