Gain of miR-151 on chromosome 8q24.3 facilitates tumour cell migration and spreading through downregulating RhoGDIA

MicroRNA as Key Players in Hepatocellular Carcinoma: Insights into Their Role in Metastasis

Liver cancer or hepatocellular carcinoma (HCC) remains the most common cancer in global epidemiology. Both the frequency and fatality of this malignancy have shown an upward trend over recent decades. Liver cancer is a significant concern due to its propensity for both intrahepatic and extrahepatic metastasis. Liver cancer metastasis is a multifaceted process characterized by cell detachment from the bulk tumor, modulation of cellular motility and invasiveness, enhanced proliferation, avoidance of the immune system, and spread either via lymphatic or blood vessels. MicroRNAs (miRNAs) are small non-coding ribonucleic acids (RNAs) playing a crucial function in the intricate mechanisms of tumor metastasis. A number of miRNAs can either increase or reduce metastasis via several mechanisms, such as control of motility, proliferation, attack by the immune system, cancer stem cell properties, altering the microenvironment, and the epithelial-mesenchymal transition (EMT). Besides, two other types of non-coding RNAs, such as long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) can competitively bind to endogenous miRNAs. This competition results in the impaired ability of the miRNAs to inhibit the expression of the specific messenger RNAs (mRNAs) that are targeted. Increasing evidence has shown that the regulatory axis comprising circRNA/lncRNA-miRNA-mRNA is correlated with the regulation of HCC metastasis. This review seeks to present a thorough summary of recent research on miRNAs in HCC, and their roles in the cellular processes of EMT, invasion and migration, as well as the metastasis of malignant cells. Finally, we discuss the function of the lncRNA/circRNA-miRNA-mRNA network as a crucial modulator of carcinogenesis and the regulation of signaling pathways or genes that are relevant to the metastasis of HCC. These findings have the potential to offer valuable insight into the discovery of novel therapeutic approaches for management of liver cancer metastasis.

m6A-dependent mature miR-151-5p accelerates the malignant process of HNSCC by targeting LYPD3

miRNA has emerged as a crucial regulator in various of pathological and physiological processes, yet its precise mechanism of action the detailed mechanism of their action in Head and neck squamous cell carcinoma (HNSCC) remains incompletely understood. This study sheds light on the role of mi-151-5p, revealing its significantly elevated expression in tumor cells, which notably enhances the invasion and migration of HNSCC cells. This effect is achieved through directly targeting LY6/PLAUR Domain Containing 3 (LYPD3) by miR-151-5p, involving complementary binding to the 3'-untranslated regions (3'-UTR) in the mRNA of LYPD3. Consequently, this interaction accelerates the metastasis of HNSCC. Notably, clinical observations indicate a correlation between high expression of miR-151-5p and low levels of LYPD3 in clinical settings are correlated with poor prognosis of HNSCC patients. Furthermore, our investigation demonstrates that glycosylation of LYPD3 modulates its subcellular localization and reinforces its role in suppressing HNSCC metastasis. Additionally, we uncover a potential regulatory mechanism involving the facilitation of miR-151-5p maturation and accumulation through N6-methyladenosine (m6A) modification. This process is orchestrated by methyltransferase-like 3 (METTL3) and mediated by a newly identified reader, heterogeneous nuclear ribonucleoprotein U (hnRNP U). These findings collectively underscore the significance of the METTL3/miR-151-5p/LYPD3 axis serves as a prominent driver in the malignant progression of HNSCC.

Understanding Gene Involvement in Hepatocellular Carcinoma: Implications for Gene Therapy and Personalized Medicine

Hepatocellular carcinoma (HCC) is the dominant type of liver cancers and is one of the deadliest health threats globally. The conventional therapeutic options for HCC are hampered by low efficiency and intolerable side effects. Gene therapy, however, now offers hope for the treatment of many disorders previously considered incurable, and gene therapy is beginning to address many of the shortcomings of conventional therapies. Herein, we summarize the involvement of genes in the pathogenesis and prognosis of HCC, with a special focus on dysregulated signaling pathways, genes involved in immune evasion, and non-coding RNAs as novel two-edged players, which collectively offer potential targets for the gene therapy of HCC. Herein, the opportunities and challenges of HCC gene therapy are discussed. These include innovative therapies such as genome editing and cell therapies. Moreover, advanced gene delivery technologies that recruit nanomedicines for use in gene therapy for HCC are highlighted. Finally, suggestions are offered for improved clinical translation and future directions in this area of endeavor.

Targeting non-coding RNAs and N6-methyladenosine modification in hepatocellular carcinoma

Hepatocellular carcinoma (HCC), the most common form of primary liver cancers, accounts for a significant portion of cancer-related death globally. However, the molecular mechanisms driving the onset and progression of HCC are still not fully understood. Emerging evidence has indicated that non-protein-coding regions of genomes could give rise to transcripts, termed non-coding RNA (ncRNA), forming novel functional driving force for aberrant cellular activity. Over the past decades, overwhelming evidence has denoted involvement of a complex array of molecular function of ncRNAs at different stages of HCC tumorigenesis and progression. In this context, several pre-clinical studies have highlighted the potentials of ncRNAs as novel therapeutic modalities in the management of human HCC. Moreover, N6-methyladenosine (m6A) modification, the most prevalent form of internal mRNA modifications in mammalian cells, is essential for the governance of biological processes within cells. Dysregulation of m6A in ncRNAs has been implicated in human carcinogenesis, including HCC. In this review, we will discuss dysregulation of several hallmark ncRNAs (miRNAs, lncRNAs, and circRNAs) in HCC and address the latest advances for their involvement in the onset and progression of HCC. We also focus on dysregulation of m6A modification and various m6A regulators in the etiology of HCC. In the end, we discussed the contemporary preclinical and clinical application of ncRNA-based and m6A-targeted therapies in HCC.

miR-424-3p promotes metastasis of hepatocellular carcinoma via targeting the SRF-STAT1/2 axis

Although emerging evidence has established the roles of miRNAs in hepatocellular carcinoma (HCC), the global functional implication of miRNAs in this malignancy remains largely uncharacterized. Here, we aim to systematically identify novel miRNAs involved in HCC and clarify the function and mechanism of specific novel candidate miRNA(s) in this malignancy. Through an integrative omics approach, we identified ten HCC-associated functional modules and a collection of candidate miRNAs. Among them, we demonstrated that miR-424-3p, exhibiting strong associations with extracellular matrix (ECM), promotes HCC cells migration and invasion in vitro and facilitates HCC metastasis in vivo. We further demonstrated that SRF is a direct functional target of miR-424-3p, and is required for the oncogenic activity of miR-424-3p. Finally, we found that miR-424-3p reduces the interferon pathway by attenuating the transactivation of SRF on STAT1/2 and IRF9 genes, which in turn enhances the matrix metalloproteinases (MMPs)-mediated ECM remodeling. This study provides comprehensive functional relevance of miRNAs in HCC by an integrative omics analysis, and further clarifies that miR-424-3p in ECM functional module plays an oncogenic role via reducing the SRF-STAT1/2 axis in this malignancy.

MiRNA-423 rs6505162 and miRNA-6811 rs2292879 SNP associated with lung cancer in Hainan, China

BACKGROUND

MicroRNAs (miRNAs) are known to exert significant influence on various physiological processes and diseases, including cancers. The primary objective of this present study was to examine the impact of eight single-nucleotide polymorphisms (SNPs) in miRNA on the susceptibility to lung cancer (LC) within the Chinese Southern population.

METHODS

The genotypes of these eight polymorphisms were determined in 132 LC patients and 214 cancer-free controls.

RESULTS

In overall analyses, GG genotype of miRNA-6811 rs2292879 polymorphism was significantly correlated with increased risk of LC (GG vs. AA, adjusted OR = 5.10, 95% CI = 1.02-25.43, P=0.047), yet the genotype frequencies of rs2292879 SNP in controls did not met the Hardy-Weinberg equilibrium (HWE) (P=0.001) in present study. Stratified analyses by smoking revealed that miRNA-423 rs6505162 variants significantly decreased the LC risk in heterozygous (CA vs. CC, adjusted OR = 0.14, 95% CI = 0.03-0.81, P=0.028) and recessive (AA vs. CA + CC, adjusted OR = 0.17, 95% CI = 0.03-0.90, P=0.038) genetic models in smoking population. However, miRNA-196A2 rs11614913, miRNA-196A2 rs12304647, miRNA-146A rs2910164, miRNA-16-1 rs1022960, miRNA-608 rs4919510, and miRNA-27a rs895819 polymorphisms were not significantly associated with LC.

CONCLUSION

The findings of our study indicate a potential decrease in LC risk among smokers with the miRNA-423 rs6505162 variants, while an increase in risk is associated with miRNA-6811 rs2292879 polymorphisms in the population of Southern Chinese. However, further well-designed research is necessary to fully understand the precise impact of these two SNPs on the development of LC.

The role of mir-151a-5p in tumorigenesis; A systematic review

BACKGROUND

Highly supported microRNAs (miRNAs) are key players in cancer development. Each of these miRNAs may act as an oncomir, a tumor-suppressor, or both in various cancers. Mir-151a-5p is believed to be one of these miRNAs with diverse roles. We have conducted this systematic review to clarify the role of mir-151a-5p in formation of various cancers.

METHODS AND MATERIALS

We searched for existing articles in PubMed, Web of Science, Cochrane, Scopus, and RNAcentral databases up to November 2022. A total of 23 articles were qualified and included in the present systematic review. This review is registered on JBI at https://jbi.global/systematic-review-register. Expression levels, diagnostic and prognostic values, biological processes, and targeted downstream genes are included.

RESULTS

Assembled data indicate the expression levels of mir-151a-5p vary from down- to up-regulated based on the type of the cancer. Its functional role depends on the genetic profile of cancerous tissue. Results mostly point to the oncogenic role of this miRNA in Pituitary adenomas, Acute Myeloid Leukemia (AML), Endometrial, Lung, Barrett's carcinogenesis, Colorectal, Myelodysplastic syndromes, Hepatocellular carcinoma and Breast cancers, as its inhibited targets seem to be controlling several signaling pathways, cell adhesion, and cell cycle. At the same time, tumor-suppressing role has also been observed only in Malignant Pleural Mesothelioma, Central Nerve System (CNS) lymphoma, Chronic Myeloid and Acute Lymphocytic Leukemia. Two types of cancers, prostate and colon, show contradictory results as there are studies supporting both up- and down-regulation in these cancers. Pituitary adenomas, Barrett's carcinogenesis and CNS lymphomas are top cancers diagnosed with mir-151-5p. However, prognostic feature is only applicable to Lung adenocarcinoma.

DISCUSSION

Based on the present findings and further studies in the future, mir-151a-5p may be used as diagnostic and prognostic biomarkers or even a therapeutic target in cancer studies.

DATA AVAILABILITY STATEMENT

The articles used in this study can be found with the defined search phrase in mentioned databases. A list of selected articles will be available on reasonable requests.

SDF-1 and NOTCH signaling in myogenic cell differentiation: the role of miRNA10a, 425, and 5100

BACKGROUND

Skeletal muscle regeneration is a complex process regulated by many cytokines and growth factors. Among the important signaling pathways regulating the myogenic cell identity are these involving SDF-1 and NOTCH. SDF-1 participates in cell mobilization and acts as an important chemoattractant. NOTCH, on the other hand, controls cell activation and myogenic determination of satellite cells. Knowledge about the interaction between SDF-1 and NOTCH signaling is limited.

METHODS

We analyzed two populations of myogenic cells isolated from mouse skeletal muscle, that is, myoblasts derived from satellite cells (SCs) and muscle interstitial progenitor cells (MIPCs). First, microRNA level changes in response to SDF-1 treatment were analyzed with next-generation sequencing (NGS). Second, myogenic cells, i.e., SC-derived myoblasts and MIPCs were transfected with miRNA mimics, selected on the basis of NGS results, or their inhibitors. Transcriptional changes, as well as proliferation, migration, and differentiation abilities of SC-derived myoblasts and MIPCs, were analyzed in vitro. Naive myogenic potential was assessed in vivo, using subcutaneous engrafts and analysis of cell contribution to regeneration of the skeletal muscles.

RESULTS

SDF-1 treatment led to down-regulation of miR10a, miR151, miR425, and miR5100 in myoblasts. Interestingly, miR10a, miR425, and miR5100 regulated the expression of factors involved in the NOTCH signaling pathway, including Dll1, Jag2, and NICD. Furthermore, miR10a, miR425, and miR5100 down-regulated the expression of factors involved in cell migration: Acta1, MMP12, and FAK, myogenic differentiation: Pax7, Myf5, Myod, Mef2c, Myog, Musk, and Myh3. However, these changes did not significantly affect myogenic cell migration or fusion either in vitro or in vivo, except when miR425 was overexpressed, or miR5100 inhibitor was used. These two molecules increased the fusion of MIPCs and myoblasts, respectively. Furthermore, miR425-transfected MIPC transplantation into injured skeletal muscle resulted in more efficient regeneration, compared to control cell transplantation. However, skeletal muscles that were injected with miR10a transfected myoblasts regenerated less efficiently.

CONCLUSIONS

SDF-1 down-regulates miR10a, miR425, and miR5100, what could affect NOTCH signaling, differentiation of myogenic cells, and their participation in skeletal muscle regeneration.

Connecting the dots in the associations between diet, obesity, cancer, and microRNAs

The prevalence of obesity has reached pandemic levels worldwide, leading to a lower quality of life and higher health costs. Obesity is a major risk factor for noncommunicable diseases, including cancer, although obesity is one of the major preventable causes of cancer. Lifestyle factors, such as dietary quality and patterns, are also closely related to the onset and development of obesity and cancer. However, the mechanisms underlying the complex association between diet, obesity, and cancer remain unclear. In the past few decades, microRNAs (miRNAs), a class of small non-coding RNAs, have been demonstrated to play critical roles in biological processes such as cell differentiation, proliferation, and metabolism, highlighting their importance in disease development and suppression and as therapeutic targets. miRNA expression levels can be modulated by diet and are involved in cancer and obesity-related diseases. Circulating miRNAs can also mediate cell-to-cell communications. These multiple aspects of miRNAs present challenges in understanding and integrating their mechanism of action. Here, we introduce a general consideration of the associations between diet, obesity, and cancer and review the current knowledge of the molecular functions of miRNA in each context. A comprehensive understanding of the interplay between diet, obesity, and cancer could be valuable for the development of effective preventive and therapeutic strategies in future.

Tumor Microenvironment Remodeling in Gastrointestinal Cancer: Role of miRNAs as Biomarkers of Tumor Invasion

Gastrointestinal (GI) cancers are the most frequent neoplasm, responsible for half of all cancer-related deaths. Metastasis is the leading cause of death from GI cancer; thus, studying the processes that regulate cancer cell migration is of paramount importance for the development of new therapeutic strategies. In this review, we summarize the mechanisms adopted by cancer cells to promote cell migration and the subsequent metastasis formation by highlighting the key role that tumor microenvironment components play in deregulating cellular pathways involved in these processes. We, therefore, provide an overview of the role of different microRNAs in promoting tumor metastasis and their role as potential biomarkers for the prognosis, monitoring, and diagnosis of GI cancer patients. Finally, we relate the possible use of nutraceuticals as a new strategy for targeting numerous microRNAs and different pathways involved in GI tumor invasiveness.

The Antibacterial Activity of Kaempferol Combined with Colistin against Colistin-Resistant Gram-Negative Bacteria

Social hygiene is seriously threatened by the rise in colistin (COL) resistance against Gram-negative bacteria (GNB). With resistance to last-line antibiotics such as COL becoming more common, it is imperative to identify alternative treatment options. In our work, we sought to determine if COL plus kaempferol (KP) present synergistic effects on the antibacterial and antibiofilm activities against colistin-resistant (Col-R) GNB in vivo and in vitro. Twenty-four Col-R GNB were collected as the experimental strains. The synergistic activity of COL and KP was evaluated by checkerboard method, time-killing assays, and the Galleria mellonella experiment. The antibiofilm effectiveness of the COL/KP combination against Col-R GNB was assessed using biofilm inhibition and eradication assays and scanning electron microscopy (SEM). Cytotoxicity tests were performed to detect the toxicity of KP monotherapy or combination therapy. There is synergistic antibacterial activity of COL and KP combination in vitro. KP combined with COL could inhibit the formation of bacterial biofilms. The amalgamation of COL and KP considerably reduced the amount of bacteria in the biofilm, according to the SEM findings. The COL/KP combination improved the survivorship of infected larvae in the G. mellonella in vivo infection model. In addition, the combination of KP and COL showed no cytotoxicity at synergistic combined concentrations according to cytotoxicity assays. This represents the first account of the antibacterial and antibiofilm activities of KP in combination with COL against Col-R GNB. Therefore, our results may provide an effective alternative route to combat Col-R GNB infections. IMPORTANCE COL is one of the few antibiotics effective against clinical isolates of GNB. However, in recent years, GNB resistance to colistin has been increasing. As a result, the combined application of colistin in conjunction with nonantibacterial medications has garnered considerable interest. In this work, the KP/COL combination showed effective antibacterial and antibiofilm activities in vitro and in vivo. The synergistic effect of combined application may be attributed to membrane permeability. Due to the low cytotoxicity of the combined concentration, the combination exhibits a promising future for use in clinical anti-infection treatments. This finding might broaden the potential applications for COL.

circTMEM181 upregulates ARHGAP29 to inhibit hepatocellular carcinoma migration and invasion by sponging miR-519a-5p

AIM

Circular RNAs (circRNAs) are a novel class of noncoding RNAs and are conserved in various species. Although numerous circRNAs have been identified, their role in cancer remains unclear.

METHODS

The expression of circTMEM181 in 90 paired human hepatocellular carcinoma (HCC) and adjacent nontumor tissues were detected using quantitative reverse transcription-polymerase chain reaction. Transwell assay was performed for functional analysis of HCC cell migration and invasion. Luciferase reporter assay was used to verify the combination of circTMEM181 and miR-519a-5p.

RESULTS

In this study, we identified a novel circRNA, named circTMEM181, was downregulated in HCC tissues. Decreased expression of circTMEM181 was associated with shorter overall survival of patients with HCC. CircTMEM181 overexpression reduced HCC cell migration and invasion abilities, while circTMEM181 knockdown increased cell motility. Mechanically, circTMEM181 could directly bind to miR-519a-5p and subsequently upregulate ARHGAP29 protein expression.

CONCLUSION

These data provide the first evidence of clinical significance and function of circTMEM181, and suggest the circTMEM181/miR-519a-5p/ARHGAP29 axis in HCC development.

Upregulation of miR-151-5p promotes the apoptosis of intestinal epithelial cells by targeting brain-derived neurotrophic factor in ulcerative colitis mice

Ulcerative colitis (UC) is the most prevalent form of chronic inflammatory bowel disease, the etiology of which is poorly understood. This study investigated the role of miR-151-5p on UC and explored the role of brain-derived neurotrophic factor (BDNF) in a UC mouse model and cell model. A UC mouse model was engineered by dextran sulfate sodium (DSS) induction. Primary mouse intestinal epithelial cells (IECs) were isolated. Colitis mice were intraperitoneally injected with miR-151-5p antagomir and antagomir negative control, and weight loss, disease activity index, and colon length of mice were measured. Colon tissues of mice were histologically analyzed. A UC cell model was constructed by treating MODE-K cells with DSS. miR-151-5p expression in the cell model was modulated by transfection. The exogenous BDNF effect on the UC cell model and intestinal cell apoptosis, viability and proliferation was detected by flow cytometry, CCK-8 and EdU experiment. The expression of miR-151-5p and apoptosis-related proteins was assessed through q-PCR and western blotting. miR-151-5p was upregulated in the colon tissues and primary IECs of colitis mice. miR-151-5p directly inhibited the expression of BNDF. miR-151-5p upregulation promoted apoptosis in UC MODE-K cells. miR-151-5p upregulation repressed the viability of UC MODE-K cells. Exogenous BNDF treatment reversed the effect of miR-151-5p on UC MODE-K cells. miR-151-5p knockdown improved UC symptoms in mice, including alleviating weight loss, reducing disease activity index and improving colon length and damaged colon tissues. miR-151-5p contributed to intestinal epithelial cells apoptosis in colitis mice via inhibiting BNDF expression.

Synthesis, biological evaluation, and molecular docking of novel hydroxyzine derivatives as potential AR antagonists

Prostate cancer (PCa) is a malignant tumor with a higher mortality rate in the male reproductive system. In this study, the hydroxyazine derivatives were synthesized with different structure from traditional anti-prostate cancer drugs. In the evaluation of in vitro cytotoxicity and antagonistic activity of PC-3, LNCaP, DU145 and androgen receptor, it was found that the mono-substituted derivatives on the phenyl group (4, 6, 7, and 9) displayed strong cytotoxic activities, and compounds 11–16 showed relatively strong antagonistic potency against AR (Inhibition% >55). Docking analysis showed that compounds 11 and 12 mainly bind to AR receptor through hydrogen bonds and hydrophobic bonds, and the structure-activity relationship was discussed based on activity data. These results suggested that these compounds may have instructive implications for drug structural modification in prostate cancer.

mRNA-miRNA networks identify metabolic pathways associated to the anti-tumorigenic effect of thyroid hormone on preneoplastic nodules and hepatocellular carcinoma

Background

Thyroid hormones (THs) inhibit hepatocellular carcinoma (HCC) through different mechanisms. However, whether microRNAs play a role in the antitumorigenic effect of THs remains unknown.

Methods

By next generation sequencing (NGS) we performed a comprehensive comparative miRNomic and transcriptomic analysis of rat hepatic preneoplastic lesions exposed or not to a short-term treatment with triiodothyronine (T3). The expression of the most deregulated miRs was also investigated in rat HCCs, and in human hepatoma cell lines, treated or not with T3.

Results

Among miRs down-regulated in preneoplastic nodules following T3, co-expression networks revealed those targeting thyroid hormone receptor-β (Thrβ) and deiodinase1, and Oxidative Phosphorylation. On the other hand, miRs targeting members of the Nrf2 Oxidative Pathway, Glycolysis, Pentose Phosphate Pathway and Proline biosynthesis – all involved in the metabolic reprogramming displayed by preneoplastic lesions– were up-regulated. Notably, while the expression of most miRs deregulated in preneoplastic lesions was not altered in HCC or in hepatoma cells, miR-182, a miR known to target Dio1 and mitochondrial complexes, was down-deregulated by T3 treatment at all stages of hepatocarcinogenesis and in hepatocarcinoma cell lines. In support to the possible critical role of miR-182 in hepatocarcinogenesis, exogenous expression of this miR significantly impaired the inhibitory effect of T3 on the clonogenic growth capacity of human HCC cells.

Conclusions

This work identified several miRNAs, so far never associated to T3. In addition, the precise definition of the miRNA-mRNA networks elicited by T3 treatment gained in this study may provide a better understanding of the key regulatory events underlying the inhibitory effect of T3 on HCC development. In this context, T3-induced down-regulation of miR-182 appears as a promising tool.

Non-Coding RNAs in Hepatocellular Carcinoma

Liver cancer ranks as the fourth leading cause of cancer-related deaths. Despite extensive research efforts aiming to evaluate the biological mechanisms underlying hepatocellular carcinoma (HCC) development, little has been translated towards new diagnostic and treatment options for HCC patients. Historically, the focus has been centered on coding RNAs and their respective proteins. However, significant advances in sequencing and RNA detection technologies have shifted the research focus towards non-coding RNAs (ncRNA), as well as their impact on HCC development and progression. A number of studies reported complex post-transcriptional interactions between various ncRNA and coding RNA molecules. These interactions offer insights into the role of ncRNAs in both the known pathways leading to oncogenesis, such as dysregulation of p53, and lesser-known mechanisms, such as small nucleolar RNA methylation. Studies investigating these mechanisms have identified prevalent ncRNA changes in microRNAs, snoRNAs, and long non-coding RNAs that can both pre- and post-translationally regulate key factors in HCC progression. In this review, we present relevant publications describing ncRNAs to summarize the impact of different ncRNA species on liver cancer development and progression and to evaluate recent attempts at clinical translation.

Transposable elements contribute to the spatiotemporal microRNA landscape in human brain development

Transposable elements (TEs) contribute to the evolution of gene regulatory networks and are dynamically expressed throughout human brain development and disease. One gene regulatory mechanism influenced by TEs is the miRNA system of post-transcriptional control. miRNA sequences frequently overlap TE loci and this miRNA expression landscape is crucial for control of gene expression in adult brain and different cellular contexts. Despite this, a thorough investigation of the spatiotemporal expression of TE-embedded miRNAs in human brain development is lacking. Here, we identify a spatiotemporally dynamic TE-embedded miRNA expression landscape between childhood and adolescent stages of human brain development. These miRNAs sometimes arise from two apposed TEs of the same subfamily, such as for L2 or MIR elements, but in the majority of cases stem from solo TEs. They give rise to in silico predicted high-confidence pre-miRNA hairpin structures, likely represent functional miRNAs, and have predicted genic targets associated with neurogenesis. TE-embedded miRNA expression is distinct in the cerebellum when compared to other brain regions, as has previously been described for gene and TE expression. Furthermore, we detect expression of previously nonannotated TE-embedded miRNAs throughout human brain development, suggestive of a previously undetected miRNA control network. Together, as with non-TE-embedded miRNAs, TE-embedded sequences give rise to spatiotemporally dynamic miRNA expression networks, the implications of which for human brain development constitute extensive avenues of future experimental research. To facilitate interactive exploration of these spatiotemporal miRNA expression dynamics, we provide the "Brain miRTExplorer" web application freely accessible for the community.

RhoGDI1 interacts with PHLDA2, suppresses the proliferation, migration, and invasion of trophoblast cells, and participates in the pathogenesis of preeclampsia

Preeclampsia (PE) is a pregnancy-associated disease, which is the major cause of mortality on maternity and perinatal infants. It is hypothesized that PE is a consequence of the dysfunction of the trophoblast cells. Pleckstrin homology-like domain, family A, member 2 (PHLDA2) was shown to inhibit the proliferation, migration, and invasion of trophoblast cells in our previous studies. However, the mechanism by which PHLDA2 affects trophoblast cell function has not been clarified. In the current study, co-immunoprecipitation (Co-IP) with mass spectroscopy analysis was used to explore the proteins that interacted with PHLDA2. A total of 291 candidate proteins were found to be associated with PHLDA2. The interaction between PHLDA2 and Rho guanine nucleotide dissociation inhibitor (RhoGDI) 1 was identified by Co-IP and immunofluorescence staining. Western blot analysis indicated that overexpression of PHLDA2 resulted in upregulation of the RhoGDI1 protein levels, which were stabilized in the presence of cycloheximide. Similarly, overexpression of RhoGDI1 promoted PHLDA2 expression and its stability. Furthermore, pull-down and Co-IP results indicated that PHLDA2 repressed the activity of Rho guanosine triphosphate hydrolase family proteins by regulating RhoGDI1 expression. In addition, RhoGDI1 expression was upregulated in the placental tissues of patients with PE. The effects of the suppression of PHLDA2 expression on proliferation, migration, and invasion of trophoblast cells were partly abrogated following knockdown of RhoGDI1. Taken together, the data indicated that RhoGDI1 mediated regulation of PHLDA2 on the biological behavior of trophoblast cells and may participate in the pathophysiology of PE.

Examples of Inverse Comorbidity between Cancer and Neurodegenerative Diseases: A Possible Role for Noncoding RNA

Cancer is one of the most common causes of death; in parallel, the incidence and prevalence of central nervous system diseases are equally high. Among neurodegenerative diseases, Alzheimer’s dementia is the most common, while Parkinson’s disease (PD) is the second most frequent neurodegenerative disease. There is a significant amount of evidence on the complex biological connection between cancer and neurodegeneration. Noncoding RNAs (ncRNAs) are defined as transcribed nucleotides that perform a variety of regulatory functions. The mechanisms by which ncRNAs exert their functions are numerous and involve every aspect of cellular life. The same ncRNA can act in multiple ways, leading to different outcomes; in fact, a single ncRNA can participate in the pathogenesis of more than one disease—even if these seem very different, as cancer and neurodegenerative disorders are. The ncRNA activates specific pathways leading to one or the other clinical phenotype, sometimes with obvious mechanisms of inverse comorbidity. We aimed to collect from the existing literature examples of inverse comorbidity in which ncRNAs seem to play a key role. We also investigated the example of mir-519a-3p, and one of its target genes Poly (ADP-ribose) polymerase 1, for the inverse comorbidity mechanism between some cancers and PD. We believe it is very important to study the inverse comorbidity relationship between cancer and neurodegenerative diseases because it will help us to better assess these two major areas of human disease.

Chenodeoxycholic acid inhibits lung adenocarcinoma progression via the integrin α5β1/FAK/p53 signaling pathway

BACKGROUND

Lung cancer is the leading cause of cancer-associated death worldwide and is classified into non-small cell lung cancer (NSCLC) and small-cell lung cancer (SCLC). NSCLC accounts for approximately 80%-85% of all lung cancer cases. Chenodeoxycholic acid (CDCA), a primary bile acid, has been reported to inhibit carcinoma cell proliferation. Here, we aimed to determine the effects and mechanism of action of CDCA against lung adenocarcinoma (LUAD).

METHODS

Western blotting and quantitative real-time polymerase chain reaction were used to evaluate the protein and mRNA expression levels in LUAD cell lines, respectively. Cell Counting Kit-8 and clone formation assays were performed to evaluate the proliferation ability of different cell types in vitro. Tumor cell motility was evaluated using Transwell assays. The transcriptional profile of A549 cells treated with CDCA was determined through RNA sequencing analysis. A xenograft model was established to evaluate the effects of CDCA on LUAD progression in vivo.

RESULTS

CDCA inhibited LUAD cell proliferation, migration, and invasion. Furthermore, it promoted apoptosis in LUAD cells. Mechanistically, CDCA inhibited the integrin α5β1 signaling pathway in LUAD cells by inhibiting the expression of the α5 and β1 subunits of integrin and phosphorylated FAK. Moreover, CDCA induced an increase in the levels of p53, a downstream gene of the integrin α5β1/FAK pathway. In addition, CDCA significantly decreased tumor volume in mice without inducing significant toxicity.

CONCLUSIONS

Our findings indicate that CDCA attenuates LUAD pathogenesis in vitro and in vivo via the integrin α5β1/FAK/p53 axis.

The miR151 and miR5100 Transfected Bone Marrow Stromal Cells Increase Myoblast Fusion in IGFBP2 Dependent Manner

Background

Bone marrow stromal cells (BMSCs) form a perivascular cell population in the bone marrow. These cells do not present naïve myogenic potential. However, their myogenic identity could be induced experimentally in vitro or in vivo. In vivo, after transplantation into injured muscle, BMSCs rarely fused with myofibers. However, BMSC participation in myofiber reconstruction increased if they were modified by NICD or PAX3 overexpression. Nevertheless, BMSCs paracrine function could play a positive role in skeletal muscle regeneration. Previously, we showed that SDF-1 treatment and coculture with myofibers increased BMSC ability to reconstruct myofibers. We also noticed that SDF-1 treatment changed selected miRNAs expression, including miR151 and miR5100.

Methods

Mouse BMSCs were transfected with miR151 and miR5100 mimics and their proliferation, myogenic differentiation, and fusion with myoblasts were analyzed.

Results

We showed that miR151 and miR5100 played an important role in the regulation of BMSC proliferation and migration. Moreover, the presence of miR151 and miR5100 transfected BMSCs in co-cultures with human myoblasts increased their fusion. This effect was achieved in an IGFBP2 dependent manner.

Conclusions

Mouse BMSCs did not present naïve myogenic potential but secreted proteins could impact myogenic cell differentiation. miR151 and miR5100 transfection changed BMSC migration and IGFBP2 and MMP12 expression in BMSCs. miR151 and miR5100 transfected BMSCs increased myoblast fusion in vitro.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s12015-022-10350-y.

Upregulation of a novel LncRNA AC104958.2 stabilized by PCBP2 promotes proliferation and microvascular invasion in hepatocellular carcinoma

Long non-coding RNAs (lncRNAs) were reported to be involved in tumorigenesis and progression of hepatocellular carcinoma (HCC). Microvascular invasion (MVI) is an independent predictor for early recurrence and overall survival in postoperative patients with HCC. However, the mechanisms how lncRNAs affect HCC and MVI remain elusive. By RNA sequencing (RNA-seq) in a series of 65 HCC samples and 30 paired adjacent non-tumor liver tissue, we identified a novel lncRNA AC104958.2 that was significantly upregulated in HCC tissues and associated with MVI. Overexpression of AC104958.2 obviously elevated cell viability, metastasis, invasion and epithelial-mesenchymal transition (EMT), while knockout of AC104958.2 mediated by CRISPR/Cas9 technique showed the opposite effects. In addition, the interaction between AC104958.2 and Poly (rC) binding protein 2 (PCBP2) was identified by RNA pull down and mass spectrometry (MS), which was further validated by RNA immunoprecipitation (RIP). PCBP2 was also upregulated in HCC and associated with MVI. High expression of both AC104958.2 and PCBP2 was correlated with tumor size, TNM stage and MVI in HCC. Overexpression of PCBP2 greatly increased the cell viability, metastasis, invasion and EMT. Moreover, actinomycin D assay showed that overexpression of PCBP2 enhanced the RNA stability of AC104958.2. In conclusion, our study showed that a novel lncRNA AC104958.2 exerted oncogenic roles in HCC and might be a promising biomarker and therapeutic target.

Partial EMT in Squamous Cell Carcinoma: A Snapshot

In the process of cancer EMT, some subgroups of cancer cells simultaneously exhibit both mesenchymal and epithelial characteristics, a phenomenon termed partial EMT (pEMT). pEMT is a plastic state in which cells coexpress epithelial and mesenchymal markers. In squamous cell carcinoma (SCC), pEMT is regulated, and the phenotype is maintained via the HIPPO pathway, NOTCH pathway and TGF-β pathways and by microRNAs, lncRNAs and the cancer microenvironment (CME); thus, SCC exhibits aggressive tumorigenic properties and high stemness, which leads collective migration and therapy resistance. Few studies have reported therapeutic interventions to address cells that have undergone pEMT, and this approach may be an effective way to inhibit the plasticity, drug resistance and metastatic potential of SCC.

NDRG1 regulates Filopodia-induced Colorectal Cancer invasiveness via modulating CDC42 activity

N-myc downstream regulated gene-1 (NDRG1) has been identified as a putative metastasis suppressor gene and proved to be a key player in cancer spreading and proliferation in our previous work. However, the effects of NDRG1 on tumor invasion and the mechanisms behind it are rarely understood. Here we provided in silico evidence that NDRG1 plays a crucial role in actin reorganization in colorectal cancer (CRC). Through in vitro experiments, we next observed filopodia formation was altered in NDRG1-modified cell lines, while cell division cycle-42 (CDC42) displayed excessive activation in NDRG1-silenced cells. Mechanistically, NDRG1 loss disrupts the binding between RhoGDIα and CDC42 and triggers the activation of CDC42 and the downstream cascades PAK1/Cofilin, thereby promotes the formation of filopodia and invasiveness of CRC. The knockdown of NDRG1 led to enhanced dissemination of CRC cells in vivo and correlates with active CDC42 expression. Using clinical sample analysis, we found an elevated level of active CDC42 in patients with advanced T stage, and it was negatively related to NDRG1 expression. In sum, these results uncover a mechanism utilized by NDRG1 to regulate CDC42 activity in coordinating cytoskeleton reorganization, which was crucial in cancer invasion.

MicroRNAs in the Pathogenesis of Hepatocellular Carcinoma: A Review

Simple Summary

Hepatocellular carcinoma (HCC) is one of the most frequently occurring cancers, and the prognosis for late-stage HCC remains poor. A better understanding of the pathogenesis of HCC is expected to improve outcomes. MicroRNAs (miRNAs) are small, noncoding, single-stranded RNAs that regulate the expression of various target genes, including those in cancer-associated genomic regions or fragile sites in various human cancers. We summarize the central roles of miRNAs in the pathogenesis of HCC and discuss their potential utility as valuable biomarkers and new therapeutic agents for HCC.

Abstract

Hepatocellular carcinoma (HCC) is the seventh most frequent cancer and the fourth leading cause of cancer mortality worldwide. Despite substantial advances in therapeutic strategies, the prognosis of late-stage HCC remains dismal because of the high recurrence rate. A better understanding of the etiology of HCC is therefore necessary to improve outcomes. MicroRNAs (miRNAs) are small, endogenous, noncoding, single-stranded RNAs that modulate the expression of their target genes at the posttranscriptional and translational levels. Aberrant expression of miRNAs has frequently been detected in cancer-associated genomic regions or fragile sites in various human cancers and has been observed in both HCC cells and tissues. The precise patterns of aberrant miRNA expression differ depending on disease etiology, including various causes of hepatocarcinogenesis, such as viral hepatitis, alcoholic liver disease, or nonalcoholic steatohepatitis. However, little is known about the underlying mechanisms and the association of miRNAs with the pathogenesis of HCC of various etiologies. In the present review, we summarize the key mechanisms of miRNAs in the pathogenesis of HCC and emphasize their potential utility as valuable diagnostic and prognostic biomarkers, as well as innovative therapeutic targets, in HCC diagnosis and treatment.

Targeting the cytoskeleton against metastatic dissemination

Cancer is a pathology characterized by a loss or a perturbation of a number of typical features of normal cell behaviour. Indeed, the acquisition of an inappropriate migratory and invasive phenotype has been reported to be one of the hallmarks of cancer. The cytoskeleton is a complex dynamic network of highly ordered interlinking filaments playing a key role in the control of fundamental cellular processes, like cell shape maintenance, motility, division and intracellular transport. Moreover, deregulation of this complex machinery contributes to cancer progression and malignancy, enabling cells to acquire an invasive and metastatic phenotype. Metastasis accounts for 90% of death from patients affected by solid tumours, while an efficient prevention and suppression of metastatic disease still remains elusive. This results in the lack of effective therapeutic options currently available for patients with advanced disease. In this context, the cytoskeleton with its regulatory and structural proteins emerges as a novel and highly effective target to be exploited for a substantial therapeutic effort toward the development of specific anti-metastatic drugs. Here we provide an overview of the role of cytoskeleton components and interacting proteins in cancer metastasis with a special focus on small molecule compounds interfering with the actin cytoskeleton organization and function. The emerging involvement of microtubules and intermediate filaments in cancer metastasis is also reviewed.

Mutational drivers of cancer cell migration and invasion

Genomic instability and mutations underlie the hallmarks of cancer-genetic alterations determine cancer cell fate by affecting cell proliferation, apoptosis and immune response, and increasing data show that mutations are involved in metastasis, a crucial event in cancer progression and a life-threatening problem in cancer patients. Invasion is the first step in the metastatic cascade, when tumour cells acquire the ability to move, penetrate into the surrounding tissue and enter lymphatic and blood vessels in order to disseminate. A role for genetic alterations in invasion is not universally accepted, with sceptics arguing that cellular motility is related only to external factors such as hypoxia, chemoattractants and the rigidity of the extracellular matrix. However, increasing evidence shows that mutations might trigger and accelerate the migration and invasion of different types of cancer cells. In this review, we summarise data from published literature on the effect of chromosomal instability and genetic mutations on cancer cell migration and invasion.

Cullin 3/KCTD5 Promotes the Ubiqutination of Rho Guanine Nucleotide Dissociation Inhibitor 1 and Regulates Its Stability

Rho guanine nucleotide dissociation inhibitor 1 (RhoGDI1) plays important roles in numerous cellular processes, including cell motility, adhesion, and proliferation, by regulating the activity of Rho GTPases. Its expression is altered in various human cancers and is associated with malignant progression. Here, we show that RhoGDI1 interacts with Cullin 3 (CUL3), a scaffold protein for E3 ubiquitin ligase complexes. Ectopic expression of CUL3 increases the ubiquitination of RhoGDI1. Furthermore, potassium channel tetramerization domain containing 5 (KCTD5) also binds to RhoGDI1 and increases its interaction with CUL3. Ectopic expression of KCTD5 increases the ubiquitination of RhoGDI1, whereas its knockdown by RNA interference has the opposite effect. Depletion of KCTD5 or expression of dominant-negative CUL3 (DN-CUL3) enhances the stability of RhoGDI1. Our findings reveal a previously unknown mechanism for controlling RhoGDI1 degradation that involves a CUL3/KCTD5 ubiquitin ligase complex.

Extracellular vesicles-derived OncomiRs mediate communication between cancer cells and cancer-associated hepatic stellate cells in hepatocellular carcinoma microenvironment

Tumor microenvironment (TME) is a critical determinant for hepatocellular carcinoma (HCC). Hepatic stellate cells (HSCs) are main interstitial cells in TME and play a vital role in early intrahepatic invasion and metastasis of HCC. The potential mechanism on the interactions between HSCs and HCC cells remains unclear. In this study, the effects of extracellular vesicles (EVs)-derived OncomiRs that mediate communication between HCC cells and cancer-associated hepatic stellate cells (caHSCs) and remold TME were investigated. The results found that the HCC cells-released EVs contained more various OncomiRs, which could activate HSCs (LX2 cells) and transform them to caHSCs, the caHSCs in turn exerted promotion effects on HCC cells through HSCs-released EVs. To further simulate the effects of OncomiRs in EVs on construction of pro-metastatic TME, a group of OncomiRs, miR-21, miR-221 and miR-151 was transfected into HCC cells and LX2 cells. These microRNAs in the EVs from OncomiRs-enhanced cells were demonstrated to have oncogenic effects on HCC cells by upregulating the activities of protein kinase B (AKT)/extracellular signal-regulated kinase (ERK) signal pathways. Equivalent results were also found in HCC xenografted tumor models. The findings suggested that the OncomiR secretion and transference by cancer cells-released EVs can mediate the communication between HCC cells and HSCs. HCC cells and caHSCs, as well as their secreted EVs, jointly construct a pro-metastatic TME suitable for invasion and metastasis of cancer cells, all these TME components form a positive feedback loop to promote HCC progression and metastasis.

MicroRNA Regulation of the Small Rho GTPase Regulators-Complexities and Opportunities in Targeting Cancer Metastasis

The small Rho GTPases regulate important cellular processes that affect cancer metastasis, such as cell survival and proliferation, actin dynamics, adhesion, migration, invasion and transcriptional activation. The Rho GTPases function as molecular switches cycling between an active GTP-bound and inactive guanosine diphosphate (GDP)-bound conformation. It is known that Rho GTPase activities are mainly regulated by guanine nucleotide exchange factors (RhoGEFs), GTPase-activating proteins (RhoGAPs), GDP dissociation inhibitors (RhoGDIs) and guanine nucleotide exchange modifiers (GEMs). These Rho GTPase regulators are often dysregulated in cancer; however, the underlying mechanisms are not well understood. MicroRNAs (miRNAs), a large family of small non-coding RNAs that negatively regulate protein-coding gene expression, have been shown to play important roles in cancer metastasis. Recent studies showed that miRNAs are capable of directly targeting RhoGAPs, RhoGEFs, and RhoGDIs, and regulate the activities of Rho GTPases. This not only provides new evidence for the critical role of miRNA dysregulation in cancer metastasis, it also reveals novel mechanisms for Rho GTPase regulation. This review summarizes recent exciting findings showing that miRNAs play important roles in regulating Rho GTPase regulators (RhoGEFs, RhoGAPs, RhoGDIs), thus affecting Rho GTPase activities and cancer metastasis. The potential opportunities and challenges for targeting miRNAs and Rho GTPase regulators in treating cancer metastasis are also discussed. A comprehensive list of the currently validated miRNA-targeting of small Rho GTPase regulators is presented as a reference resource.

A colorimetric detection of microRNA-148a in gastric cancer by gold nanoparticle-RNA conjugates

For the early diagnosis of gastric cancer, microRNA-148a (miRNA-148a) as a promising biomarker is measured by a simple colorimetric biosensor due to its unique surface plasmon resonance (SPR) absorption of gold nanoparticles (AuNPs). In the assay system, the sensing probes are facilitated by the conjugation of AuNPs with RNA probes (RNA_P) via Au-S bonds, which align in a tail-to-tail fashion onto the target RNA. When miRNA-148a is introduced, a sandwich hybridization reaction is triggered between the AuNP-RNA_P conjugates and targets, resulting in changes in the SPR absorption band, microscopic distribution and macroscopic color of the AuNP solution. Following this principle, this colorimetric method is able to quantitatively detect miRNA-148a at nanomolar level with a limit of ∼1.9 nM, and exhibits high sensitivity and selectivity by a low-cost UV-vis spectrometer or even the naked eye. Moreover, the AuNP network materials with a characteristic sharp 'melting transition' provide significant guidance for the reusability of DNA or RNA biosensors.

Gastric cancer proliferation and invasion is reduced by macrocalyxin C via activation of the miR-212-3p/Sox6 Pathway

Gastric cancer is a malignancy of very poor prognosis and survival rates. Macrocalyxin C is a Chinese herb-derived diterpenoid compound that has been postulated to possess anti-cancer characteristics. Gastic cell viability and stage of cell cycle were assessed using CCK8 assay and flow cytometry, respectively. Cell migration and invation were assessed using the wound healing and Transwell assays. Rate of apoptosis was determined via AV/PI-staining. Athymic nude mice xenograft models were used to evaluate the in vivo efficacy of macrocalyxin C. Western blot, luciferase experiments, cell transfection and real-time PCR allowed further study into the activation of the miR-212-3p/Sox6 pathway during macrocalyxin C treatment. We conclude that macrocalyxin C may halt the proliferation of gastric malignancies through alteration of cell invasion, apoptosis, progression through the cell cycle and cell growth. The macrocalyxin C→miR-212-3p┤Sox6 signal pathway was identified to be involved in Sox6 attenuation through augmentation of miR-212-3p values.

FAM3A plays crucial roles in controlling PDX1 and insulin expressions in pancreatic beta cells

So far, the mechanism that links mitochondrial dysfunction to PDX1 inhibition in the pathogenesis of pancreatic β cell dysfunction under diabetic condition remains largely unclear. This study determined the role of mitochondrial protein FAM3A in regulating PDX1 expression in pancreatic β cells using gain- and loss-of function methods in vitro and in vivo. Within pancreas, FAM3A is highly expressed in β, α, δ, and pp cells of islets. Islet FAM3A expression was correlated with insulin expression under physiological and diabetic conditions. Mice with specific knockout of FAM3A in islet β cells exhibited markedly blunted insulin secretion and glucose intolerance. FAM3A-deficient islets showed significant decrease in PDX1 expression, and insulin expression and secretion. FAM3A overexpression upregulated PDX1 and insulin expressions, and augmented insulin secretion in cultured islets and β cells. Mechanistically, FAM3A enhanced ATP production to elevate cellular Ca²⁺ level and promote insulin secretion. Furthermore, FAM3A-induced ATP release activated CaM to function as a co-activator of FOXA2, stimulating PDX1 gene transcription. In conclusion, FAM3A plays crucial roles in controlling PDX1 and insulin expressions in pancreatic β cells. Inhibition of FAM3A will trigger mitochondrial dysfunction to repress PDX1 and insulin expressions.

Expression analysis of LTR-derived miR-1269a and target gene, KSR2 in Sebastes schlegelii

BACKGROUND

Sebastes schlegelii are an important species of fish found in the coastal areas of the Korea with significant commercial importance. Most studies thus far have been primarily focused on environmental factors; behavioural patterns, aquaculture, diseases and limited genetic studies with little to none related to either microRNAs (miRNAs) or transposable elements (TE).

OBJECTIVES

In order to understand biological roles of TE-derived miR-1269a, we examined expression pattern for miR-1269a and its target gene, KSR2, in various tissues of Sebastes schlegelii. Also, we performed luciferase reporter assay in HINAE cells.

METHODS

UCSC Genome Browser (https://genome.ucsc.edu/) was used to examine which TE is associated with miR-1269a. For the target genes for miR-1269a, the target genes associated with the miRNA were identified using miRDB (http://www.mirdb.org/) and TargetScan 7.1 (http://www.targetscan.org/vert_71/). A two-step miRNA kit, HB miR Multi Assay Kit™ System. I was used for the analysis of TE-derived miRNA expression patterns. The 3'UTR of KSR2 gene was cloned into the psiCHECK-2 vector. Subsequently co-transfected with miR-1269a mimics to HINAE cells for luciferase reporter assay.

RESULTS

MiR-1269a was found to be derived from LTR retrotransposon, MLT2B. LTR-derived miR-1269a was highly expressed in the muscle, liver and gonad tissues of Sebastes schlegelii, but KSR2 revealed high expression in the brain. Co-transfection of KSR2 and miR-1269a mimic to HINAE cells showed high activity of miR-1269a in relation to KSR2.

CONCLUSION

LTR-derived miR-1269a showed enhancer activity with relation to KSR2 in Sebastes schlegelii. The data may be used as a foundation for further investigation regarding correlation of miRNA and target genes in addition to other functional studies of biological significance in Sebastes schlegelii.

miR-140 Attenuates the Progression of Early-Stage Osteoarthritis by Retarding Chondrocyte Senescence

Osteoarthritis (OA) is a major cause of joint pain and disability, and chondrocyte senescence is a key pathological process in OA and may be a target of new therapeutics. MicroRNA-140 (miR-140) plays a protective role in OA, but little is known about its epigenetic effect on chondrocyte senescence. In this study, we first validated the features of chondrocyte senescence characterized by increased cell cycle arrest in the G0/G1 phase and the expression of senescence-associated β-galactosidase (SA-βGal), p16^INK4a, p21, p53, and γH2AX in human knee OA. Then, we revealed in interleukin 1β (IL-1β)-induced OA chondrocytes in vitro that pretransfection with miR-140 effectively inhibited the expression of SA-βGal, p16^INK4a, p21, p53, and γH2AX. Furthermore, in vivo results from trauma-induced early-stage OA rats showed that intra-articularly injected miR-140 could rapidly reach the chondrocyte cytoplasm and induce molecular changes similar to the in vitro results, resulting in a noticeable alleviation of OA progression. Finally, bioinformatics analysis predicted the potential targets of miR-140 and a mechanistic network by which miR-140 regulates chondrocyte senescence. Collectively, miR-140 can effectively attenuate the progression of early-stage OA by retarding chondrocyte senescence, contributing new evidence of the involvement of miR-mediated epigenetic regulation of chondrocyte senescence in OA pathogenesis.

Role of Non-Coding RNAs in the Progression of Liver Cancer: Evidence from Experimental Models

Liver cancer is a devastating cancer that ranges from relatively rare (around 2% of all cancers in the United States) to commonplace (up to 50% of cancers in underdeveloped countries). Depending upon the stage of pathogenesis, prognosis, or functional liver tissue present, transplantation or partial hepatectomy may be the only available treatment option. However, due to the rise in metabolic syndrome and the increasing demand for livers, patients often wait months or years for available organs. Due to this shortage, doctors must have other treatment options available. One promising area of cancer research lies in understanding the role of regulatory non-coding RNAs (ncRNAs) as oncogenic drivers and potential targets for prospective therapies. While the role of these ncRNAs was not initially clear, many of them have since been recognized to function as important players in the regulation of gene expression, epigenetic modification, and signal transduction in both normal and cancer cell cycles. Dysregulation of these different ncRNA subtypes has been implicated in the pathogenesis and progression of many major cancers including hepatocellular carcinoma. This review summarizes current findings on the roles noncoding RNAs play in the progression of liver cancer and the various animal models used in current research to elucidate those data.

Regulation of Rho GTPases by RhoGDIs in Human Cancers

Rho GDP dissociation inhibitors (RhoGDIs) play important roles in various cellular processes, including cell migration, adhesion, and proliferation, by regulating the functions of the Rho GTPase family. Dissociation of Rho GTPases from RhoGDIs is necessary for their spatiotemporal activation and is dynamically regulated by several mechanisms, such as phosphorylation, sumoylation, and protein interaction. The expression of RhoGDIs has changed in many human cancers and become associated with the malignant phenotype, including migration, invasion, metastasis, and resistance to anticancer agents. Here, we review how RhoGDIs control the function of Rho GTPases by regulating their spatiotemporal activity and describe the regulatory mechanisms of the dissociation of Rho GTPases from RhoGDIs. We also discuss the role of RhoGDIs in cancer progression and their potential uses for therapeutic intervention.

Lnc-UCID Promotes G1/S Transition and Hepatoma Growth by Preventing DHX9-Mediated CDK6 Down-regulation

Although thousands of long noncoding RNAs (lncRNAs) have been annotated, only a limited number of them have been functionally characterized. Here, we identified an oncogenic lncRNA, named lnc-UCID (lncRNA up-regulating CDK6 by interacting with DHX9). Lnc-UCID was up-regulated in hepatocellular carcinoma (HCC), and a higher lnc-UCID level was correlated with shorter recurrence-free survival of HCC patients. Both gain-of-function and loss-of function studies revealed that lnc-UCID enhanced cyclin-dependent kinase 6 (CDK6) expression and thereby promoted G1/S transition and cell proliferation. Studies from mouse xenograft models revealed that tumors derived from lnc-UCID-silenced HCC cells had a much smaller size than those from control cells, and intratumoral injection of lnc-UCID small interfering RNA suppressed xenograft growth. Mechanistically, the 850-1030-nt domain of lnc-UCID interacted physically with DEAH (Asp-Glu-Ala-His) box helicase 9 (DHX9), an RNA helicase. On the other hand, DHX9 post-transcriptionally suppressed CDK6 expression by binding to the 3'-untranslated region (3'UTR) of CDK6 mRNA. Further investigation disclosed that lnc-UCID enhanced CDK6 expression by competitively binding to DHX9 and sequestering DHX9 from CDK6-3'UTR. In an attempt to explore the mechanisms responsible for lnc-UCID up-regulation in HCC, we found that the lnc-UCID gene was frequently amplified in HCC. Furthermore, miR-148a, whose down-regulation was associated with an increase of lnc-UCID in HCC, could bind lnc-UCID and inhibit its expression. Conclusion: Up-regulation of lnc-UCID, which may result from amplification of its gene locus and down-regulation of miR-148a, can promote HCC growth by preventing the interaction of DHX9 with CDK6 and subsequently enhancing CDK6 expression. These findings provide insights into the biological functions of lncRNAs, the regulatory network of cell cycle control, and the mechanisms of HCC development, which may be exploited for anticancer therapy.

An ARF6-Exportin-5 axis delivers pre-miRNA cargo to tumour microvesicles

Tumor-derived microvesicles (TMVs) comprise a class of extracellular vesicles released from tumor cells that are now understood to facilitate communication between the tumor and the surrounding microenvironment. Despite their significance, the regulatory mechanisms governing the trafficking of bioactive cargos to TMVs at the cell surface remain poorly defined. Here we describe a molecular pathway for the delivery of microRNA (miRNA) cargo to nascent TMVs involving the dissociation of a pre-miRNA/Exportin-5 complex from Ran-GTP following nuclear export, and its subsequent transfer to a cytoplasmic shuttle comprised of ARF6-GTP and GRP1. As such, ARF6 activation increases pre-miRNA cargo contained within TMVs via a process that requires casein kinase 2-mediated phosphorylation of Ran-GAP1. Further, TMVs were found to contain pre-miRNA processing machinery including Dicer and Argonaute 2, which allow for cell-free pre-miRNA processing within shed vesicles. These findings offer cellular targets to block the loading and processing of pre-miRNAs within TMVs.

MiR-HCC2 Up-regulates BAMBI and ELMO1 Expression to Facilitate the Proliferation and EMT of Hepatocellular Carcinoma Cells

MicroRNAs (miRNAs) are a class of gene expression regulators that participate in the occurrence and development of hepatocellular carcinoma (HCC), although the underlying mechanism by which they function in HCC has not been fully elucidated. Here, small RNA deep sequencing was used to identify aberrantly expressed miRNAs in HCC tissues, and a novel miRNA named miR-HCC2 was identified. RT-qPCR analysis demonstrated that miR-HCC2 displayed higher expression in HCC tissues than in adjacent non-tumor tissues. We documented that miR-HCC2 facilitated the growth, migration and invasion of HCC cells by accelerating cell cycle progression, incressing the expression of epithelial-to-mesenchymal transition (EMT)-associated marker vimentin but decreasing the expression of E-cadherin. MiR-HCC2 directly targeted the 3′ UTR of BAMBI and ELMO1 and up-regulated their expression. Both BAMBI and ELMO1 had the same patterns of expression with miR-HCC2 in HCC tissues. Additionally, blocking BAMBI or ELMO1 counteracted the phenotypic alterations elicited by miR-HCC2. Collectively, our investigation identified miR-HCC2 as a new positive modulator of HCC aggressiveness that may serve as a potential biomarker for the development of diagnostic and therapeutic approaches for HCC.

miRNA-365b promotes hepatocellular carcinoma cell migration and invasion by downregulating SGTB

Aim: miR-365b, a miRNA at chromosomal breakpoint, was often amplified and upregulated in human hepatocellular carcinoma (HCC). However, the role of miR-365b dysregulation remains unclear. Materials & methods: miR-365b function assays and its target gene analyses were performed. Results: We revealed that miR-365b promoted HCC cell motility and spreading. Furthermore, SGTB was found to be a downstream target of miR-365b, and knockdown of the SGTB gene could mimic the effect of miR-365b in hastening HCC cell migration and invasion. Conclusion: These results imply that miR-365b plays a tumor-promoting role in HCC by suppressing SGTB expression, offering novel potential targets for the treatment of HCC.

Predicting Postoperative Liver Dysfunction Based on Blood-Derived MicroRNA Signatures

There is an urgent need for an easily assessable preoperative test to predict postoperative liver function recovery and thereby determine the optimal time point of liver resection, specifically as current markers are often expensive, time consuming, and invasive. Emerging evidence suggests that microRNA (miRNA) signatures represent potent diagnostic, prognostic, and treatment-response biomarkers for several diseases. Using next-generation sequencing as an unbiased systematic approach, 554 miRNAs were detected in preoperative plasma of 21 patients suffering from postoperative liver dysfunction (LD) after liver resection and 27 matched controls. Subsequently, we identified a miRNA signature-consisting of miRNAs 151a-5p, 192-5p, and 122-5p-that highly correlated with patients developing postoperative LD after liver resection. The predictive potential for postoperative LD was subsequently confirmed using real-time PCR in an independent validation cohort of 98 patients. Ultimately, a regression model of the two miRNA ratios 151a-5p to 192-5p and 122-5p to 151a-5p was found to reliably predict postoperative LD, severe morbidity, prolonged intensive care unit and hospital stays, and even mortality before an operation with a remarkable accuracy, thereby outperforming established markers of postoperative LD. Ultimately, we documented that miRNA ratios closely followed liver function recovery after partial hepatectomy. Conclusion: Our data demonstrate the clinical utility of an miRNA-based biomarker to support the selection of patients undergoing partial hepatectomy. The dynamical changes during liver function recovery indicate a possible role in individualized patient treatment. Thereby, our data might help to tailor surgical strategies to the specific risk profile of patients.

Tumor-secreted GRP78 facilitates the migration of macrophages into tumors by promoting cytoskeleton remodeling

Glucose-regulated protein 78 (GRP78), an important molecular chaperone in the endoplasmic reticulum, is often over-expressed in the central region of advanced tumor and acts as a promoter of tumor progression. As main immune cells in the tumor microenvironment, infiltration of abundant macrophages into advanced tumor further facilitates growth of tumor. Although has potential association between GRP78 and infiltration of macrophages, its underlying mechanisms are poorly understood. Here, we report that secreted GRP78 facilitates recruitment of macrophages into tumors both in vitro and in vivo. Further studies reveal that secreted GRP78 transports into macrophages and bound to intracellular Ca²⁺, which lead to uneven distribution of Ca²⁺ and subsequent polarization of macrophages. The polarization of macrophages activates expression of microRNA-200b-3p. By directly targeting RhoGDI, miR-200b-3p stimulates the activity of RhoGTPase and ultimately leads to the distribution of GTP-Rac1 and GTP-Cdc42 in front protrusion and GTP-RhoA in rear contraction, which further results in migration of macrophages in a certain direction. Our results reveal a novel function of GRP78 to promote the recruitment of macrophages to tumor and provide a potential therapeutic target for malignancies.

LINE-2 transposable elements are a source of functional human microRNAs and target sites

Transposable elements (TEs) are dynamically expressed at high levels in multiple human tissues, but the function of TE-derived transcripts remains largely unknown. In this study, we identify numerous TE-derived microRNAs (miRNAs) by conducting Argonaute2 RNA immunoprecipitation followed by small RNA sequencing (AGO2 RIP-seq) on human brain tissue. Many of these miRNAs originated from LINE-2 (L2) elements, which entered the human genome around 100–300 million years ago. L2-miRNAs derived from the 3’ end of the L2 consensus sequence and thus shared very similar sequences, indicating that L2-miRNAs could target transcripts with L2s in their 3’UTR. In line with this, many protein-coding genes carried fragments of L2-derived sequences in their 3’UTR: these sequences served as target sites for L2-miRNAs. L2-miRNAs and their targets were generally ubiquitously expressed at low levels in multiple human tissues, suggesting a role for this network in buffering transcriptional levels of housekeeping genes. In addition, we also found evidence that this network is perturbed in glioblastoma. In summary, our findings uncover a TE-based post-transcriptional network that shapes transcriptional regulation in human cells.

Transposable elements (TEs) are repetitive sequences, that have contributed to the landscaping of the genome by jumping into new positions and amplifying in number. TEs have been suggested to play a role in gene regulation, but it remains poorly understood how they contribute to this process. In this study, we show that in various human tissues, an ancient class of TEs give rise to small non-coding RNAs, called microRNAs (miRNAs), that are important regulators of gene expression. The same class of TEs also serves as target sites for these TE-derived miRNAs when they are part of protein-coding transcripts. We also provide evidence that TE-derived miRNAs and target sites may play a role in human disease, as they are dysregulated in aggressive brain tumors. Altogether, our study provides novel insight into how TEs acting as miRNAs play a role in gene regulation in both, healthy and diseased human tissues.

A unique insight into the MiRNA profile during genital chlamydial infection

Background

Genital C. trachomatis infection may cause pelvic inflammatory disease (PID) that can lead to tubal factor infertility (TFI). Understanding the pathogenesis of chlamydial complications including the pathophysiological processes within the female host genital tract is important in preventing adverse pathology. MicroRNAs regulate several pathophysiological processes of infectious and non-infectious etiologies. In this study, we tested the hypothesis that the miRNA profile of single and repeat genital chlamydial infections will be different and that these differences will be time dependent. Thus, we analyzed and compared differentially expressed mice genital tract miRNAs after single and repeat chlamydia infections using a C. muridarum mouse model. Mice were sacrificed and their genital tract tissues were collected at 1, 2, 4, and 8 weeks after a single and repeat chlamydia infections. Histopathology, and miRNA sequencing were performed.

Results

Histopathology presentation showed that the oviduct and uterus of reinfected mice were more inflamed, distended and dilated compared to mice infected once. The miRNAs expression profile was different in the reproductive tissues after a reinfection, with a greater number of miRNAs expressed after reinfection. Also, the number of miRNAs expressed each week after chlamydia infection and reinfection varied, with weeks eight and one having the highest number of differentially expressed miRNAs for chlamydia infection and reinfection respectively. Ten miRNAs; mmu-miR-378b, mmu-miR-204-5p, mmu-miR-151-5p, mmu-miR-142-3p, mmu-miR-128-3p, mmu-miR-335-3p, mmu-miR-195a-3p, mmu-miR-142-5p, mmu-miR-106a-5p and mmu-miR-92a-3p were common in both primary chlamydia infection and reinfection. Pathway analysis showed that, amongst other functions, the differentially regulated miRNAs control pathways involved in cellular and tissue development, disease conditions and toxicity.

Conclusions

This study provides insights into the changes in miRNA expression over time after chlamydia infection and reinfection, as well as the pathways they regulate to determine pathological outcomes. The miRNAs networks generated in our study shows that there are differences in the focus molecules involved in significant biological functions in chlamydia infection and reinfection, implying that chlamydial pathogenesis occurs differently for each type of infection and that this could be important when determining treatments regime and disease outcome. The study underscores the crucial role of host factors in chlamydia pathogenesis.

Electronic supplementary material

The online version of this article (10.1186/s12864-019-5495-6) contains supplementary material, which is available to authorized users.

Serum MicroRNAs as Biomarkers in Hepatitis C: Preliminary Evidence of a MicroRNA Panel for the Diagnosis of Hepatocellular Carcinoma

Early diagnosis of cirrhosis and hepatocellular carcinoma (HCC) due to chronic Hepatitis C (CHC) remain clinical priorities. In this pilot study, we assessed serum microRNA (miRNA) expression to distinguish cirrhosis and HCC, alone and in combination with the aminotransferase-to-platelet ratio (APRI), Fibrosis 4 (FIB-4), and alpha-fetoprotein (AFP). Sixty CHC patients were subdivided into 3 cohorts: Mild disease (fibrosis stage F0-2; n = 20); cirrhosis (n = 20); and cirrhosis with HCC (n = 20). Circulating miRNA signatures were determined using a liver-specific real-time quantitative reverse transcription PCR (qRT-PCR) microarray assessing 372 miRNAs simultaneously. Differentially-expressed miRNA candidates were independently validated using qRT-PCR. Serum miRNA-409-3p was increased in cirrhosis versus mild disease. In HCC versus cirrhosis, miRNA-486-5p was increased, whereas miRNA-122-5p and miRNA-151a-5p were decreased. A logistic regression model-generated panel, consisting of miRNA-122-5p + miRNA-409-3p, distinguished cirrhosis from mild disease (area under the curve, AUC = 0.80; sensitivity = 85%, specificity = 70%; p < 0.001). When combined with FIB-4 or APRI, performance was improved with AUC = 0.89 (p < 0.001) and 0.87 (p < 0.001), respectively. A panel consisting of miRNA-122-5p + miRNA-486-5p + miRNA-142-3p distinguished HCC from cirrhosis (AUC = 0.94; sensitivity = 80%, specificity = 95%; p < 0.001), outperforming AFP (AUC = 0.64, p = 0.065). Serum miRNAs are differentially expressed across the spectrum of disease severity in CHC. MicroRNAs have great potential as diagnostic biomarkers in CHC, particularly in HCC where they outperform the only currently-used biomarker, AFP.

miR-151-5p modulates APH1a expression to participate in contextual fear memory formation

Long-term memory formation requires gene expression and new protein synthesis. MicroRNAs (miRNAs), a family of small non-coding RNAs that inhibit target gene mRNA expression, are involved in new memory formation. In this study, elevated miR-151-5p (miR-151) levels were found to be responsible for hippocampal contextual fear memory formation. Using a luciferase reporter assay, we demonstrated that miR-151 targets APH1a, a protein that has been identified as a key factor in γ-secretase activity, namely APH1a. Blocking miR-151 can upregulate APH1a protein levels and subsequently impair hippocampal fear memory formation. These results indicate that miR-151 is involved in hippocampal contextual fear memory by inhibiting APH1a protein expression. This work provides novel evidence for the role of miRNAs in memory formation and demonstrates the implication of APH1a protein in miRNA processing in the adult brain.

microRNAs: Key players in virus-associated hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is known as one of the major health problems worldwide. Pathological analysis indicated that a variety of risk factors including genetical (i.e., alteration of tumor suppressors and oncogenes) and environmental factors (i.e., viruses) are involved in beginning and development of HCC. The understanding of these risk factors could guide scientists and clinicians to design effective therapeutic options in HCC treatment. Various viruses such as hepatitis B virus (HBV) and hepatitis C virus (HCV) via targeting several cellular and molecular pathways involved in HCC pathogenesis. Among various cellular and molecular targets, microRNAs (miRNAs) have appeared as key players in HCC progression. miRNAs are short noncoding RNAs which could play important roles as oncogenes or tumor suppressors in several malignancies such as HCC. Deregulation of many miRNAs (i.e., miR-222, miR-25, miR-92a, miR-1, let-7f, and miR-21) could be associated with different stages of HCC. Besides miRNAs, exosomes are other particles which are involved in HCC pathogenesis via targeting different cargos, such as DNAs, RNAs, miRNAs, and proteins. In this review, we summarize the current knowledge of the role of miRNAs and exosomes as important players in HCC pathogenesis. Moreover, we highlighted HCV- and HBV-related miRNAs which led to HCC progression.