Synthetic miR-145 mimic inhibits multiple myeloma cell growth in vitro and in vivo

Muscone suppresses gastric cancer via regulation of miRNA-145

This study aims to determine the effects and mechanism of action of muscone on the biological activity of the gastric cancer cell lines SGC-7901 and MGC-803 (proliferation, apoptosis, invasion, and migration) in vitro. An optimal muscone concentration was determined using MTT and cell apoptosis tests. The SGC-7901 and MGC-803 cells were divided into five groups: normal control, muscone, miRNA, muscone + miRNA, and muscone + miRNA inhibitor. Cell proliferation rate, apoptosis rate, cell cycle phase distribution, number of invading cells, and wound healing rate were compared among the five groups using MTT, flow cytometry, transwell, and wound healing assays. Relative expression levels of the proteins PI3K, AKT, P21, c-Myc, MMP-2, and MMP-9 were measured by Western blot. Compared with the control group, the groups treated with muscone and miRNA showed significantly lower cell proliferation rate, number of invading cells, and wound healing rate (p < .05 for all), but significantly higher rates of cell apoptosis rate and numbers of cells in the G1 phase (p < .05 for all). These groups also showed significantly lower expression of the proteins PI3K, AKT, c-Myc, MMP-2, and MMP-9 but significantly increased expression of the protein P21 (p < .05). Transfecting muscone-treated SGC-7901 and MGC-803 cells with miRNA-145 inhibitor resulted in a significant recovery of biological activity (p < .05). Muscone suppresses the biological activity of SGC-7901 and MGC-803 gastric cancer cells in vitro via regulation of miRNA-145.

MicroRNAs as a Potential New Preventive Approach in the Transition from Asymptomatic to Symptomatic Multiple Myeloma Disease

Simple Summary

Multiple myeloma (MM) is the second most common haematologic malignancy, and it remains an incurable disease despite the advances of novel therapies. It is characterised by a multistep process that arises from a pre-malignant asymptomatic status-defined monoclonal gammopathy of undetermined significance (MGUS), evolves to a middle stage named smouldering myeloma phase (SMM), and culminates in the active disease (MM). Identification of early and non-invasive markers of the disease progression is currently an active field of investigation. In this review, we discuss the role and significance of microRNAs (miRNAs) as potential diagnostic biomarkers to predict the clinical transition from MGUS/SMM status to MM.

Abstract

Multiple myeloma (MM) is a hematological malignancy characterised by proliferation of clonal plasma cells (PCs) within the bone marrow (BM). Myelomagenesis is a multi-step process which goes from an asymptomatic phase, defined as monoclonal gammopathy of undetermined significance (MGUS), to a smouldering myeloma (SMM) stage, to a final active MM disease, characterised by hypercalcemia, renal failure, bone lesions anemia, and higher risk of infections. Overall, microRNAs (miRNAs) have shown to significantly impact on MM tumorigenesis, as a result of miRNA-dependent modulation of genes involved in pathways known to be crucial for MM pathogenesis and disease progression. We aim to revise the literature related to the role of miRNAs as potential diagnostic and prognostic biomarkers, thus highlighting their key role as novel players within the field of MM and related premalignant conditions.

miRNA-Based Therapies in B Cell Non-Hodgkin Lymphoma

Non-Hodgkin lymphoma (NHL) is a diverse class of hematological cancers, many of which arise from germinal center (GC)-experienced B cells. Thus GCs, the sites of antibody affinity maturation triggered during immune responses, also provide an environment that facilitates B cell oncogenic transformation. miRNAs provide attractive and mechanistically different strategies to treat these malignancies based on their potential for simultaneous modulation of multiple targets. Here, we discuss the scientific rationale for miRNA-based therapeutics in B cell neoplasias and review recent advances that may help establish a basis for novel candidate miRNA-based therapies for B cell-NHL (B-NHL).

MIR145-3p promotes autophagy and enhances bortezomib sensitivity in multiple myeloma by targeting HDAC4

Multiple myeloma (MM) is an incurable plasma cell malignancy with poor survival. Autophagy, a stress-responsive catabolic process mediated by lysosomal activity, plays a crucial role in the pathophysiology of MM. Growing evidence has indicated that dysregulated microRNAs (miRNAs) are associated with the aberrant autophagy in various human cancers. However, to date, few miRNAs have been reported to directly modulate autophagy in the pathobiology of MM. In this study, we investigated the role of MIR145-3p (microRNA 145-3p) in MM, with focus on cellular processes autophagy and cell death. Our results provided evidence that downregulation of MIR145-3p expression was associated with disease progression in human MM. MIR145-3p triggered autophagic flux through direct targeting of HDAC4 (histone deacetylase 4) in MM cells, leading to enhanced apoptosis. Silencing HDAC4 recapitulated the effects of MIR145-3p, whereas enforced expression of HDAC4 abrogated the effects of MIR145-3p. Furthermore, we showed that suppression of HDAC4 by MIR145-3p resulted in upregulation of the pro-apoptotic protein BCL2L11 and caused MTORC1 inactivation, which in turn led to enhanced autophagy and cell death. Importantly, we demonstrated that MIR145-3p mimic could potentiate the anti-MM activity of bortezomib in both in vitro and in vivo experiments. Overall, our findings indicate that MIR145-3p exerted a tumor suppression function in MM by inducing autophagic cell death and suggest that MIR145-3p-based targeted therapy would represent a novel strategy for MM treatment.Abbreviations: 3-MA: 3-methyladenine; 3'-UTR: 3'-untranslated region; 7-AAD: 7-aminoactinomycin D; ACTB: actin beta; ANXA5: annexin A5; ATG5: autophagy related 5; ATG7: autophagy related 7; B2M: beta-2-microglobulin; BAF: bafilomycin A1; BCL2L11: BCL2 like 11; Bort: bortezomib; CASP3: caspase 3; CCK-8: Cell Counting Kit-8; CQ: chloroquine; Ct: threshold cycle; ctrl: control; DAPI: 4',6-diamidino-2-phenylindole; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GFP: green fluorescent protein; HDAC4: histone deacetylase 4; ISS: International Staging System; MAP1LC3B: microtubule associated protein 1 light chain 3 beta; miRNAs: microRNAs; MIR145-3p: microRNA 145-3p; MM: multiple myeloma; mRNA: messenger RNA; MTOR: mechanistic target of rapamycin kinase; MTORC1: mechanistic target of rapamycin kinase complex 1; PCs: plasma cells; PFS: progression-free survival; qRT-PCR: quantitative reverse transcription PCR; RPS6KB1: ribosomal protein S6 kinase B1; SD: standard deviation; siRNA: small interfering RNA; SQSTM1: sequestosome 1; STV: starvation; TUBB: tubulin beta class I.

[Association of miRNA-196b-5p and miRNA-99a-5p with autophagy and apoptosis in multiple myeloma cells]

目的

探讨多发性骨髓瘤（MM）细胞miRNA-196b-5p和miRNA-99a-5p表达与自噬和凋亡的关系。

方法

以人MM细胞株U266细胞及45例MM患者瘤细胞为研究对象，以40例健康体检者为对照，采用实时定量PCR法测定细胞中miRNA-196b-5p和miRNA-99a-5p表达水平，采用Western blot法测定自噬相关蛋白（LC3-Ⅱ、LC3-Ⅰ、P62、Beclin-1）、凋亡相关分子（CL caspase3、CL caspase7、Bcl-2、Bax）和TGF-β/Smad通路相关蛋白（TGF-β1、Smad2/3、p-Smad3、Smad7）表达水平，采用流式细胞术测定细胞凋亡率，分析miRNA表达水平与MM患者临床特征的相关性。

结果

①与正常浆细胞比较，U266细胞、MM患者瘤细胞的miRNA-196b-5p表达显著增加（0.43±0.15对2.44±0.63、2.02±0.85，P值均<0.001），miRNA-99a-5p表达显著降低（1.87±0.61对0.62±0.15、0.80±0.33，P值均<0.001），LC3-Ⅱ/LC3-Ⅰ、Beclin-1、Bcl-2表达显著增加，P62、Bax、CL caspase3、CL caspase7表达显著降低，细胞凋亡率降低（P值均<0.05）。②正常CD138⁺浆细胞分别转染miRNA-196b-5p mimic或miRNA-99a-5p inhibitor 48 h后，与未转染对照组比较，LC3-Ⅱ/LC3-Ⅰ、Beclin-1、TGF-β1、p-Smad3表达显著增高，P62、Smad7表达显著降低，细胞凋亡率减少（P值均<0.05）；上述反应体系加入自噬抑制剂3-甲基腺嘌呤后，细胞凋亡率未见明显改变（P值均>0.05）。③miRNA-196b-5p和miRNA-99a-5p表达与MM患者DS分期（P值分别为0.004、0.012）、ISS分期显著相关（P值均为0.001）。

结论

miRNA-196b-5p和miRNA-99a-5p表达与MM患者临床特征密切相关，miRNA-196b-5p过表达和miRNA-99a-5p表达下调通过上调自噬水平抑制骨髓瘤细胞凋亡，其机制与活化TGF-β/Smad信号通路有关。

The relationship between microRNAs and Rab family GTPases in human cancers

microRNAs (miRNAs), as a group of noncoding RNAs, posttranscriptionally control gene expression by binding to 3'-untranslated region (3'-UTR). Ras-associated binding (Rab) proteins function as molecular switches for regulating vesicular transport, which mainly have oncogenic roles in cancer development and preventing the efficacy of chemotherapies. Increased evidence supported that miRNAs/Rabs interaction have been determined as potential therapeutics for cancer therapy. Nevertheless, instability and cross-targeting of miRNAs are main limitations of using miRNA-based therapeutic. The mutual interplay between Rabs and miRNAs has been poorly understood. In the present review, we focused on the essence and activity of these molecules in cancer pathogenesis. Also, numerous hindrances and potential methods in the expansion of miRNA as an anticancer therapeutics are mentioned.

MicroRNA replacement therapy in cancer

Despite the recent progress in cancer management approaches, the mortality rate of cancer is still growing and there are lots of challenges in the clinics in terms of novel therapeutics. MicroRNAs (miRNA) are regulatory small noncoding RNAs and are already confirmed to have a great role in regulating gene expression level by targeting multiple molecules that affect cell physiology and disease development. Recently, miRNAs have been introduced as promising therapeutic targets for cancer treatment. Regulatory potential of tumor suppressor miRNAs, which enables regulation of entire signaling networks within the cells, makes them an interesting option for developing cancer therapeutics. In this regard, over recent decades, scientists have aimed at developing powerful and safe targeting approaches to restore these suppressive miRNAs in cancerous cells. The present review summarizes the function of miRNAs in tumor development and presents recent findings on how miRNAs have served as therapeutic agents against cancer, with a special focus on tumor suppressor miRNAs (mimics). Moreover, the latest investigations on the therapeutic strategies of miRNA delivery have been presented.

Regulatory mechanisms of miR-145 expression and the importance of its function in cancer metastasis

MicroRNAs are post-transcriptional mediators of gene expression and regulation, which play influential roles in tumorigenesis and cancer metastasis. The expression of tumor suppressor miR-145 is reduced in various cancer cell lines, containing both solid tumors and blood malignancies. However, the responsible mechanisms of its down-regulation are a complicated network. miR-145 is potentially able to inhbit tumor cell metastasis by targeting of multiple oncogenes, including MUC1, FSCN1, Vimentin, Cadherin, Fibronectin, Metadherin, GOLM1, ARF6, SMAD3, MMP11, Snail1, ZEB1/2, HIF-1α and Rock-1. This distinctive role of miR-145 in the regulation of metastasis-related gene expression may introduce miR-145 as an ideal candidate for controlling of cancer metastasis by miRNA replacement therapy. The present review aims to discuss the current understanding of the different aspects of molecular mechanisms of miR-145 regulation as well as its role in r metastasis regulation.

MicroRNA-145-3p suppresses proliferation and promotes apotosis and autophagy of osteosarcoma cell by targeting HDAC4

Studies have shown that miR-145-3p functions as a tumor suppressor and is associated with tumor growth and metastasis. This study intends to uncover the mechanism of a tumor suppressor of miR-145-3p. The expressions of miR-194 in osteosarcoma cell lines and tissues were monitored by real-time PCR. The proliferation ability was examined by MTT assay. The apoptosis and autophagy of cells were monitored by flow cytometry and microcopy, respectively. The regulation of miR-145-3p on HDAC4 was determined by luciferase assays and western blot assay. The results showed that miR-145-3p was significantly reduced in the osteosarcoma compared with the normal bone tissue. Overexpression of miR-145-3p significantly attenuated the proliferation and induced the apoptosis and autophagy of osteosarcoma cells. Furthermore, we demonstrated that miR-145-3p has inhibited the malignant behavior of osteosarcoma by down-regulating HDAC4 expression. These findings suggested that miR-145-3p may act as a tumor suppressor in osteosarcoma. MiR-145-3p/HDAC4 may be a novel therapeutic target in treatment of osteosarcoma.

The potential function of microRNAs as biomarkers and therapeutic targets in multiple myeloma

Multiple myeloma (MM), accounting for ~1% of all types of human cancer and 13% of all hematological malignancies, is characterized by the malignant proliferation of monoclonal plasma cells (PCs) in the bone marrow. MM leads to end stage organ impairment, including bone lesions, renal dysfunction, hypercalcemia and anemia. So far, the specific pathogenesis of MM remains unclear and no early-stage sensitive biomarker of MM has been well characterized. Furthermore, treating MM is difficult, as the majority of patients eventually relapse or become refractory following treatment using presently available methods. To date, a number of studies have demonstrated that microRNAs (miRNAs) may serve crucial functions in the progression of numerous cancers, including MM. During the tumorigenesis and pathogenesis of MM, there are multiple carcinogenic events that involve the pernicious transformation from normal to malignant PCs. miRNAs, as oncogenes or tumor suppressors, regulate MM progression-related signaling pathways. In the present review, the up-to-date preliminary basic studies and associated clinical works on the underlying mechanisms of aberrant miRNA profiling in MM have been summarized, including an evaluation of its value as a potential biomarker and a novel therapeutic strategy for MM.

MicroRNA-145 inhibits the activation of the mTOR signaling pathway to suppress the proliferation and invasion of invasive pituitary adenoma cells by targeting AKT3 in vivo and in vitro

Purpose

This study was designed to explore how miR-145 regulates the mTOR signaling pathway in invasive pituitary adenoma (IPA) by targeting AKT3.

Methods

A total of 71 cases of IPA tissues and 66 cases of non-IPA tissues were obtained in this study. In vitro, the IPA cells were assigned into blank control, empty plasmid, miR-145 mimic, miR-145 inhibitor, miR-145 mimic + rapamycin, miR-145 inhibitor + rapamycin and rapamycin groups. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting were performed to detect the protein expressions of PI3K, AKT3, mTOR mRNA and the mRNA expression of miR-145 both in vivo and in vitro. Additionally, the S6K and RPS6 mRNA and protein expressions as well as the relative phosphorylation levels were determined in vitro. MTT assay, flow cytometry and transwell assay were used to testify the cell proliferation, apoptosis and invasion ability, respectively.

Results

The IPA tissues exhibited significantly lower expression of miR-145 but higher PI3K, AKT3 and mTOR mRNA and protein expressions when compared with the non-IPA tissues. Compared with the blank control and empty plasmid groups, the miR-145 mimic group showed significantly decreased PI3K, AKT3, mTOR, S6K and RPS6 mRNA and protein expressions as well as phosphorylation levels; besides, the IPA cell proliferation, migration and invasion ability were strongly inhibited, accompanied with the increased number of apoptotic cells. In the miR-145 inhibitor group, the PI3K, AKT3, mTOR, S6K and RPS6 mRNA and protein expressions as well as the phosphorylation levels were significantly increased; cell proliferation, migration and invasion ability were remarkably elevated, accompanied with reduced apoptotic cell number.

Conclusion

The study demonstrates that miR-145 inhibits the mTOR signaling pathway to suppress the IPA cell proliferation and invasion and promotes its apoptosis by targeting AKT3.

Targeting MicroRNAs in Cancer Gene Therapy

MicroRNAs (miRNAs) are a kind of conserved small non-coding RNAs that participate in regulating gene expression by targeting multiple molecules. Early studies have shown that the expression of miRNAs changes significantly in different tumor tissues and cancer cell lines. It is well acknowledged that such variation is involved in almost all biological processes, including cell proliferation, mobility, survival and differentiation. Increasing experimental data indicate that miRNA dysregulation is a biomarker of several pathological conditions including cancer, and that miRNA can exert a causal role, as oncogenes or tumor suppressor genes, in different steps of the tumorigenic process. Anticancer therapies based on miRNAs are currently being developed with a goal to improve outcomes of cancer treatment. In our present study, we review the function of miRNAs in tumorigenesis and development, and discuss the latest clinical applications and strategies of therapy targeting miRNAs in cancer.

MicroRNAs in multiple myeloma and related bone disease

MicroRNAs (miRNAs) are short non coding RNAs aberrantly expressed in solid and hematopoietic malignancies where they play a pivotal function as post-transcriptional regulators of gene expression. Recent reports have unveiled a central role of miRNAs in multiple myeloma onset and progression and preclinical findings are progressively disclosing their potential therapeutic value as drugs or targets. In this review, we provide the basic insights of miRNA biology and function, showing how these molecules are extensively dysregulated in malignant plasma cells (PC) and related microenvironment, thus favoring clone survival and proliferation. We here describe how these critical activities have recently been evaluated to design miRNA-based therapies against multiple myeloma cells and its surrounding microenvironment.