MicroRNA-122 associates with serum apolipoprotein B but not liver fibrosis markers in CHC genotype 1 infection

The Multifaceted Roles of MicroRNA-181 in Stem Cell Differentiation and Cancer Stem Cell Plasticity

Stem cells are undifferentiated or partially differentiated cells with an extraordinary ability to self-renew and differentiate into various cell types during growth and development. The epithelial-mesenchymal transition (EMT), a critical developmental process, enhances stem cell-like properties in cells, and is associated with both normal stem cell function and the formation of cancer stem cells. Cell stemness and the EMT often coexist and are interconnected in various contexts. Cancer stem cells are a critical tumor cell population that drives tumorigenesis, cancer progression, drug resistance, and metastasis. Stem cell differentiation and the generation of cancer stem cells are regulated by numerous molecules, including microRNAs (miRNAs). These miRNAs, particularly through the modulation of EMT-associated factors, play major roles in controlling the stemness of cancer stem cells. This review presents an up-to-date summary of the regulatory roles of miR-181 in human stem cell differentiation and cancer cell stemness. We outline studies from the current literature and summarize the miR-181-controlled signaling pathways responsible for driving human stem cell differentiation or the emergence of cancer stem cells. Given its critical role in regulating cell stemness, miR-181 is a promising target for influencing human cell fate. Modulation of miR-181 expression has been found to be altered in cancer stem cells' biological behaviors and to significantly improve cancer treatment outcomes. Additionally, we discuss challenges in miRNA-based therapies and targeted delivery with nanotechnology-based systems.

Use of steric blocking antisense oligonucleotides for the targeted inhibition of junction containing precursor microRNAs

Antisense oligonucleotides (ASOs) are widely used as therapeutics for neurodegenerative diseases, cancers, and virus infections. One class of ASOs functions to enhance protein expression by sequestering the mature microRNA (miRNA) in a double-stranded structure within the RNA-induced silencing complex (RISC). An alternative approach for the targeted control of gene expression is to use ASOs that bind to the pre-elements of miRNAs (pre-miRNAs) and modulate their enzymatic processing. Here, we demonstrate that ASOs can be used to disrupt a specific structural feature, "junction," within pre-miR-31 that is important in directing efficient processing by the Dicer/TRBP complex. Furthermore, we extend and validate this strategy to pre-miR-144, which has a similar junction-dependent structure-function relationship. We found that a significant number of human pre-miRNAs are predicted to contain junctions, and validated our ASO approach on several members of this group. Importantly, we also verified the application of junction-targeting ASOs for the specific inhibition of pre-miRNA processing in cell. Our study reemphasizes the important roles of RNA structure in regulating Dicer/TRBP processing of pre-miRNAs and provides the framework to develop structure-informed ASOs that serve to inhibit miRNA production.

MicroRNA: trends in clinical trials of cancer diagnosis and therapy strategies

As a type of short noncoding RNAs, microRNA (miRNA) undoubtedly plays a crucial role in cancer development. Since the discovery of the identity and clinical functions of miRNAs, over the past few decades, the roles of miRNAs in cancer have been actively investigated. Numerous pieces of evidence indicate that miRNAs are pivotal factors in most types of cancer. Recent cancer research focused on miRNAs has identified and characterized a large cohort of miRNAs commonly dysregulated in cancer or exclusively dysregulated in specific types of cancer. These studies have suggested the potential of miRNAs as biomarkers in the diagnosis and prognostication of cancer. Moreover, many of these miRNAs have oncogenic or tumor-suppressive functions. MiRNAs have been the focus of research given their potential clinical applications as therapeutic targets. Currently, various oncology clinical trials using miRNAs in screening, diagnosis, and drug testing are underway. Although clinical trials studying miRNAs in various diseases have been reviewed before, there have been fewer clinical trials related to miRNAs in cancer. Furthermore, updated results of recent preclinical studies and clinical trials of miRNA biomarkers and drugs in cancer are needed. Therefore, this review aims to provide up-to-date information on miRNAs as biomarkers and cancer drugs in clinical trials.

A novel regulatory facet for hypertriglyceridemia: The role of microRNAs in the regulation of triglyceride-rich lipoprotein biosynthesis

Atherosclerotic cardiovascular disease (ASCVD) is one of the major leading global causes of death. Genetic and epidemiological studies strongly support the causal association between triacylglycerol-rich lipoproteins (TAGRL) and atherogenesis, even in statin-treated patients. Recent genetic evidence has clarified that variants in several key genes implicated in TAGRL metabolism are strongly linked to the increased ASCVD risk. There are several triacylglycerol-lowering agents; however, new therapeutic options are in development, among which are miRNA-based therapeutic approaches. MicroRNAs (miRNAs) are small non-coding RNAs (18-25 nucleotides) that negatively modulate gene expression through translational repression or degradation of target mRNAs, thereby reducing the levels of functional genes. MiRNAs play a crucial role in the development of hypertriglyceridemia as several miRNAs are dysregulated in both synthesis and clearance of TAGRL particles. MiRNA-based therapies in ASCVD have not yet been applied in human trials but are attractive. This review provides a concise overview of current interventions for hypertriglyceridemia and the development of novel miRNA and siRNA-based drugs. We summarize the miRNAs involved in the regulation of key genes in the TAGRLs synthesis pathway, which has gained attention as a novel target for therapeutic applications in CVD.

Distinct miRNAs associated with various clinical presentations of SARS-CoV-2 infection

MicroRNAs (miRNAs) have been shown to play important roles in viral infections, but their associations with SARS-CoV-2 infection remain poorly understood. Here, we detected 85 differentially expressed miRNAs (DE-miRNAs) from 2,336 known and 361 novel miRNAs that were identified in 233 plasma samples from 61 healthy controls and 116 patients with COVID-19 using the high-throughput sequencing and computational analysis. These DE-miRNAs were associated with SASR-CoV-2 infection, disease severity, and viral persistence in the patients with COVID-19, respectively. Gene ontology and KEGG pathway analyses of the DE-miRNAs revealed their connections to viral infections, immune responses, and lung diseases. Finally, we established a machine learning model using the DE-miRNAs between various groups for classification of COVID-19 cases with different clinical presentations. Our findings may help understand the contribution of miRNAs to the pathogenesis of COVID-19 and identify potential biomarkers and molecular targets for diagnosis and treatment of SARS-CoV-2 infection.

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2,336 known and 361 novel miRNAs identified in this study

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85 miRNAs associated with COVID-19

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A panel of miRNAs targeting the viral or cellular genes

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Machine learning using miRNAs for classification of COVID-19

Mechanisms Underlying Hepatitis C Virus-Associated Hepatic Fibrosis

Hepatitis C virus (HCV) infection often causes liver diseases, including fibrosis, cirrhosis and hepatocellular carcinoma (HCC). Liver fibrosis is the outcome of the wound healing response to tissue damage caused by chronic HCV infection. This process is characterized by the excessive accumulation of extracellular matrix (ECM) proteins, such as collagen fibers secreted by activated hepatic stellate cells (HSCs). Activation of HSCs from the quiescent stage is mediated by different mechanisms, including pro-inflammatory cytokines and chemokines released from HCV-infected hepatocytes and liver macrophages. HCV infection modulates the expression of different microRNAs that can be transported and delivered to the HSCs via exosomes released from infected cells, also leading to the development of advanced disease pathogenesis. Although recent advancements in direct-acting antiviral (DAA) treatment can efficiently control viremia, there are very few treatment strategies available that can be effective at preventing pathogenesis in advanced liver fibrosis or cirrhosis in patients. Assessment of fibrosis is considered to be the major part of proper patient care and decision making in clinical practice. In this review, we highlighted the current knowledge of molecular mechanisms responsible for the progression of liver fibrosis in chronically HCV-infected patients, and currently available methods for evaluation of fibrosis in patients. A detailed understanding of these aspects at the molecular level may contribute to the development of new therapies targeting HCV-related liver fibrosis.

Rapid Changes in Serum Lipid Profiles during Combination Therapy with Daclatasvir and Asunaprevir in Patients Infected with Hepatitis C Virus Genotype 1b

Background/Aims

Changes in lipid profiles in patients infected with hepatitis C virus (HCV) during direct-acting antiviral therapy have been reported in recent years. However, the clinical aspects of disturbed lipid metabolism in chronic HCV infection have not been fully elucidated.

Methods

Dynamic changes in serum total, low-density lipoprotein (LDL), and high-density lipoprotein (HDL) cholesterol and apolipoprotein levels in patients infected with HCV genotype 1b were examined during combination therapy with daclatasvir (DCV) and asunaprevir (ASV).

Results

Total, LDL−, and HDL-cholesterol levels increased rapidly and persistently after week 4. Apolipoprotein (apo) A-I, apo B, apo C-II, and apo C-III levels were significantly higher at week 4 than at week 0. In contrast, apo A-II and apo E levels were significantly lower. The differences in LDL− and HDL-cholesterol levels were positively correlated with those of apo B and apo A-I, respectively. Interestingly, in patients with non-sustained virological response, these cholesterol levels decreased rapidly after viral breakthrough or viral relapse. Furthermore, similar changes were observed for apo A-I, apo B and apo C-III levels.

Conclusions

Clearance of HCV using combination therapy with DCV and ASV results in rapid changes in serum lipid profiles, suggesting an influence of HCV infection on disturbed lipid metabolism.