MiR-9 promotes multiple myeloma progression by regulating TRIM56/NF-κB pathway

The effect of microRNA-9 overexpression on inhibition of melanoma cancer stem cells tumorigenicity

Most of the studies have reported the downregulation of miR-9 in metastatic melanomas compared to primary tumors. They indicated that miR-9 negatively regulates the epithelial-to-mesenchymal transition (EMT) by inhibiting SNAIL1 expression and consequently promotes CDH1 expression. Since the process of EMT is associated to stem cell features, it could be interesting to study the effect of miR-9 on melanoma cancer stem cells. In the present study, we examined the effects of miR-9 manipulation on the stemness potential of melanoma cells. Our data demonstrated that the overexpression of miR-9 in A375 and NA8 cells significantly inhibits the ability of proliferation, self-renewal, migration, and tumorigenicity of melanoma cells which was concomitant with changes in the level of BRAF , some EMT factors, and stemness genes. Likewise, the reduction of miR-9 levels led to an increase in cell proliferation, colony and sphere formation, and the ability of cell migration and tumorigenicity. In conclusion, our results specified the role of miR-9 as a tumor suppressor miRNA to inhibit many aspects of melanoma stem cells, and therefore, it could be a potential candidate for the suppression of melanoma growth and progression.

Intricate confrontation: Research progress and application potential of TRIM family proteins in tumor immune escape

BACKGROUND

Tripartite motif (TRIM) family proteins have more than 80 members and are widely found in various eukaryotic cells. Most TRIM family proteins participate in the ubiquitin-proteasome degradation system as E3-ubiquitin ligases; therefore, they play pivotal regulatory roles in the occurrence and development of tumors, including tumor immune escape. Due to the diversity of functional domains of TRIM family proteins, they can extensively participate in multiple signaling pathways of tumor immune escape through different substrates. In current research and clinical contexts, immune escape has become an urgent problem. The extensive participation of TRIM family proteins in curing tumors or preventing postoperative recurrence and metastasis makes them promising targets.

AIM OF REVIEW

The aim of the review is to make up for the gap in the current research on TRIM family proteins and tumor immune escape and propose future development directions according to the current progress and problems.

KEY SCIENTIFIC CONCEPTS OF REVIEW

This up-to-date review summarizes the characteristics and biological functions of TRIM family proteins, discusses the mechanisms of TRIM family proteins involved in tumor immune escape, and highlights the specific mechanism from the level of structure-function-molecule-pathway-phenotype, including mechanisms at the level of protein domains and functions, at the level of molecules and signaling pathways, and at the level of cells and microenvironments. We also discuss the application potential of TRIM family proteins in tumor immunotherapy, such as possible treatment strategies for combination targeting TRIM family protein drugs and checkpoint inhibitors for improving cancer treatment.

Gastrodia elata specific miRNA attenuates neuroinflammation via modulating NF-κB signaling pathway

AIMS

Based on our previous research on the specific miRNAs identified from Gastrodia elata, we selected Gas-miR2-3p to investigate its effects on neuroinflammation via in vitro and in vivo experiments.

RESULTS

RT-qPCR analysis indicated that G. elata specific Gas-miR2-3p was detected in all murine tissues post-oral administration, suggesting their potential as orally bioavailable miRNA. The analysis of RT-qPCR, Western blotting and ELISA assays consistently demonstrate that the expression of inflammatory factors as TNF-α, IL-6, IL-1β was decreased and the expression levels of p-p65 and p-IκBα were downregulated after the action of Gas-miR2-3p in both cell and animal experiments.

CONCLUSION

Gas-miR2-3p can attenuate neuroinflammation by regulating the inflammation factors and suppressing the activation of the NF-κB signaling pathway. Our findings indicate that G. elata miRNAs, as novel active components, perform a modulatory role in the NF-κB signaling pathway associated with neuroinflammation in a cross-species way.

The Functions of TRIM56 in Antiviral Innate Immunity and Tumorigenesis

As a member of the TRIM (tripartite motif) protein family, TRIM56 can function as an E3 ubiquitin ligase. In addition, TRIM56 has been shown to possess deubiquitinase activity and the ability to bind RNA. This adds to the complexity of the regulatory mechanism of TRIM56. TRIM56 was initially found to be able to regulate the innate immune response. In recent years, its role in direct antiviral and tumor development has also attracted the interest of researchers, but there is no systematic review on TRIM56. Here, we first summarize the structural features and expression of TRIM56. Then, we review the functions of TRIM56 in TLR and cGAS-STING pathways of innate immune response, the mechanisms and structural specificity of TRIM56 against different types of viruses, and the dual roles of TRIM56 in tumorigenesis. Finally, we discuss the future research directions regarding TRIM56.

Curcumol inhibits the malignant progression of prostate cancer and regulates the PDK1/AKT/mTOR pathway by targeting miR‑9

Curcumol has been reported to exert anti-tumor activity, but its intrinsic molecular mechanism in prostate cancer remains to be elucidated. The present study aimed to analyze the effect of curcumol on prostate cancer and identify its possible internal regulatory pathway using in vitro cell culture and in vivo tumor model experiments. The cytotoxicity of curcumol was detected using a Cell Counting Kit-8 assay and it was found that curcumol had no obvious toxicity or side effects on RWPE-1 cells. Wound healing, Transwell and flow cytometry assays demonstrated that curcumol could affect the activity of PC3 cells. The luciferase reporter assay also indicated that microRNA (miR)-9 could directly target pyruvate dehydrogenase kinase 1 (PDK1). After PC3 cells were transfected with miR-9 inhibitor or treated with curcumol, the expression levels of the PDK1/AKT/mTOR signaling pathway-related proteins [PDK1, phosphorylated (p)-AKT and p-mTOR] were increased or decreased, respectively. Next, the prostate cancer cell xenograft model was established. Tumor size and the expression levels of PDK1/AKT/mTOR signaling pathway-related factors were altered following treatment with curcumol. The in vitro and in vivo experiments collectively demonstrated that curcumol could inhibit the PDK1/AKT/mTOR signaling pathway by upregulating the expression level of miR-9. The present study found that curcumol regulates the PDK1/AKT/mTOR signaling pathway via miR-9 and affects the development of prostate cancer. These findings could provide a possible scientific insight for research into treatments for prostate cancer.

Identification of TRIM56 as a Potential Biomarker for Lung Adenocarcinoma

Background

Lung adenocarcinoma (LUAD) is the primary subtype of human lung cancer. The effectiveness of treatment and long-term survival of patients with LUAD are current suboptimal. Tripartite motif containing 56 (TRIM56) is a member of the TRIM protein family that have functions predominantly in immunity and cancer.

Purpose

To investigate the expression of TRIM56 in LUAD, and explore the potential regulatory role of TRIM56 in the invasion and migration of LUAD cells.

Methods

The Gene Expression Omnibus datasets and The Cancer Genome Atlas-LUAD cohort were used to analyze the mRNA expression of TRIM56 in LUAD. The differential expression profiles of miRNAs associated with TRIM56 were obtained from The Cancer Genome Atlas-LUAD cohort. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed to determine the principal functions of miRNAs and interacting proteins. Transwell and wound healing were used to detect the effect of overexpression of TRIM56 on the invasion and migration of LUAD cells.

Results

The expression of TRIM56 was decreased in LUAD and associated with poor prognosis. We determined the genome copy number, negatively correlated miRNA and potential transcription factors of TRIM56, and conducted enrichment analysis. Among them, hsa-mir-542 and hsa-mir-627 were the most likely to inhibit the expression of TRIM56. We also predicted the interacting proteins and potential ubiquitination substrate of TRIM56. Finally, we demonstrated that overexpression of TRIM56 inhibits the invasion and migration of LUAD cells.

Conclusion

This study is the first to analyze the expression of TRIM56 and its inhibitory effect on the invasion and migration of LUAD. This evidence provides a new direction for further study of the reasons for the low expression of TRIM56 in LUAD and its regulatory mechanism.

miR-744-5p Inhibits Multiple Myeloma Proliferation, Epithelial Mesenchymal Transformation and Glycolysis by Targeting SOX12/Wnt/β-Catenin Signaling

Purpose

This study investigated the function and molecular mechanisms of miR-744-5p in multiple myeloma (MM).

Methods

miR-744-5p and SRY-related high-mobility-group box 12 (SOX12) expression in clinical tissues and MM cells was monitored by quantitative real-time polymerase chain reactions and Western blot. miR-744-5p expression in MM cells was regulated by transfection. Cell proliferation was researched by cell counting kit-8 assay and plate clone formation experiment. Transwell experiment was utilized for migration and invasion detection. Glycolysis test was conducted for the detection of glucose uptake and lactate production of MM cells. The relationship between miR-744-5p and SOX12 was determined by dual-luciferase reporter gene assay and RNA pull-down experiment. In vivo experiment was conducted using nude mice.

Results

miR-744-5p expression was reduced in MM patients (P<0.01). Low miR-744-5p expression was associated with lower 60-month survival in MM patients (P=0.0402). miR-744-5p overexpression inhibited MM cells proliferation, invasion, migration, glucose uptake, lactate production, and epithelial mesenchymal transformation (EMT) (P<0.01). miR-744-5p directly inhibited SOX12 expression. miR-744-5p silencing promoted MM cells proliferation, invasion, migration, glucose uptake, lactate production, and EMT by elevating SOX12 (P<0.01). miR-744-5p inhibited the growth of MM xenograft tumors in vivo (P<0.001).

Conclusion

miR-744-5p inhibits MM cells proliferation, invasion, migration, EMT, and glycolysis by targeting SOX12/Wnt/β-catenin.

Revisiting cancer hallmarks: insights from the interplay between oxidative stress and non-coding RNAs

Cancer is one of the most common disease worldwide, with complex changes and certain traits which have been described as “The Hallmarks of Cancer.” Despite increasing studies on in-depth investigation of these hallmarks, the molecular mechanisms associated with tumorigenesis have still not yet been fully defined. Recently, accumulating evidence supports the observation that microRNAs and long noncoding RNAs (lncRNAs), two main classes of noncoding RNAs (ncRNAs), regulate most cancer hallmarks through their binding with DNA, RNA or proteins, or encoding small peptides. Reactive oxygen species (ROS), the byproducts generated during metabolic processes, are known to regulate every step of tumorigenesis by acting as second messengers in cancer cells. The disturbance in ROS homeostasis leads to a specific pathological state termed “oxidative stress”, which plays essential roles in regulation of cancer progression. In addition, the interplay between oxidative stress and ncRNAs is found to regulate the expression of multiple genes and the activation of several signaling pathways involved in cancer hallmarks, revealing a potential mechanistic relationship involving ncRNAs, oxidative stress and cancer. In this review, we provide evidence that shows the essential role of ncRNAs and the interplay between oxidative stress and ncRNAs in regulating cancer hallmarks, which may expand our understanding of ncRNAs in the cancer development from the new perspective.

Knockdown of long non-coding RNA plasmacytoma variant translocation 1 inhibits cell proliferation while promotes cell apoptosis via regulating miR-486-mediated CDK4 and BCAS2 in multiple myeloma

AIMS

This study aimed to investigate the effect of long non-coding RNA-plasmacytoma variant translocation 1 (lnc-Pvt1) knockdown on regulating cell proliferation and apoptosis, and to explore its molecular mechanism in multiple myeloma (MM).

METHODS

Lnc-Pvt1 expression was detected in MM cell lines (NCI-H929, U-266, LP-1 and RPMI-8226 cell lines) and human normal plasma cells. In U-266 cells and LP-1 cells, control shRNA and lnc-Pvt1 shRNA plasmids were transferred. Rescue experiments were further performed by transfection of lnc-Pvt1 shRNA alone and lnc-Pvt1 shRNA and miR-486 shRNA plasmids. Cells proliferation, apoptosis, RNA expression, and protein expression were determined by cell counting kit-8, annexin V-FITC-propidium iodide, quantitative polymerase chain reaction, and Western blot assays, respectively.

RESULTS

Lnc-Pvt1 expression was increased in MM cell lines (NCI-H929, U-266 and LP-1 cell lines) compared with human normal plasma cells. In U-266 cells, lnc-Pvt1 shRNA suppressed cell proliferation while enhanced cell apoptosis compared with control shRNA. Also, lnc-Pvt1 shRNA increased miR-486 expression compared with control shRNA. Further rescue experiment revealed that miR-486 shRNA did not change lnc-Pvt1 level, but increased CDK4 and BCAS2 expressions in lnc-Pvt1 knockdown-treated cells. In addition, miR-486 shRNA promoted cell proliferation while inhibited cell apoptosis in lnc-Pvt1 knockdown-treated cells. These results were further validated in LP-1 cells.

CONCLUSIONS

Lnc-Pvt1 knockdown inhibits cell proliferation and induces cell apoptosis through potentially regulating miR-486-mediated CDK4 and BCAS2 in MM.

Regulatory mechanisms of B cell responses and the implication in B cell-related diseases

Terminally differentiated B cell, the plasma cell, is the sole cell type capable of producing antibodies in our body. Over the past 30 years, the identification of many key molecules controlling B cell activation and differentiation has elucidated the molecular pathways for generating antibody-producing plasma cells. Several types of regulation modulating the functions of the important key molecules in B cell activation and differentiation add other layers of complexity in shaping B cell responses following antigen exposure in the absence or presence of T cell help. Further understanding of the mechanisms contributing to the proper activation and differentiation of B cells into antibody-secreting plasma cells may enable us to develop new strategies for managing antibody humoral responses during health and disease. Herein, we reviewed the effect of different types of regulation, including transcriptional regulation, post-transcriptional regulation and epigenetic regulation, on B cell activation, and on mounting memory B cell and antibody responses. We also discussed the link between the dysregulation of the abovementioned regulatory mechanisms and B cell-related disorders.

Aging, Melatonin, and the Pro- and Anti-Inflammatory Networks

Aging and various age-related diseases are associated with reductions in melatonin secretion, proinflammatory changes in the immune system, a deteriorating circadian system, and reductions in sirtuin-1 (SIRT1) activity. In non-tumor cells, several effects of melatonin are abolished by inhibiting SIRT1, indicating mediation by SIRT1. Melatonin is, in addition to its circadian and antioxidant roles, an immune stimulatory agent. However, it can act as either a pro- or anti-inflammatory regulator in a context-dependent way. Melatonin can stimulate the release of proinflammatory cytokines and other mediators, but also, under different conditions, it can suppress inflammation-promoting processes such as NO release, activation of cyclooxygenase-2, inflammasome NLRP3, gasdermin D, toll-like receptor-4 and mTOR signaling, and cytokine release by SASP (senescence-associated secretory phenotype), and amyloid-β toxicity. It also activates processes in an anti-inflammatory network, in which SIRT1 activation, upregulation of Nrf2 and downregulation of NF-κB, and release of the anti-inflammatory cytokines IL-4 and IL-10 are involved. A perhaps crucial action may be the promotion of macrophage or microglia polarization in favor of the anti-inflammatory phenotype M2. In addition, many factors of the pro- and anti-inflammatory networks are subject to regulation by microRNAs that either target mRNAs of the respective factors or upregulate them by targeting mRNAs of their inhibitor proteins.