An Insight into the Roles of MicroRNAs and Exosomes in Sarcoma

Advances in electrochemical biosensors for the detection of tumor-derived exosomes

Exosomes, released from diverse cells as nanoscale lipid bilayer vesicles, mediate intercellular communication and participate in various physiological and pathological processes. Thereinto, tumor-derived exosomes (T-EXOs) with molecular cargoes of parent tumor cells act as attractive biomarkers for tumor liquid biopsy. The amount of T-EXOs and their levels of contained specific proteins and nucleic acids are closely associated with cancer burden and classification. Nevertheless, the nanoscale size and relatively low abundance of exosomes, as well as complex body liquid matrix pose daunting challenges for efficient isolation and sensitive detection of T-EXOs. Biosensing as fast, convenient and accurate method, has been widely employed for the detection of biomarkers over the past decades. Among them, electrochemical sensors can sensitively detect biomarkers by measuring of the change of electrical signal caused by oxidation or reduction at the working electrode surface. This review aims to summarize the recent advance in electrochemical biosensors for quantification, and protein and RNA analysis of exosomes. Further, challenges and future perspectives for exosome-based liquid biopsy have been discussed.

Novel Detection and Clinical Utility of Serum-Derived Extracellular Vesicle in Angiosarcoma

Cutaneous angiosarcoma is a rare and highly aggressive skin malignancy. The aim of this study is to explore the alteration of serum-derived extracellular vesicle (EV) in angiosarcoma patients and to evaluate its clinical utility as a novel circulating biomarker. In a microarray analysis to examine the differential expression of specific EV-associated microRNAs in sera between cutaneous angiosarcoma patients and healthy controls, 73 microRNAs with significant upregulation and 100 microRNAs with significant downregulation, respectively, were identified in patients with angio-sarcoma. Among them, quantitative PCR confirmed that miR-184, miR-3925-5p, miR-3926, and miR-5703 were upregulated in sera of cutaneous angiosarcoma patients compared with those of healthy controls and melanoma patients. Additionally, these 4 microRNAs were expressed more highly in angiosarcoma cell lines compared with normal human endothelial cell lines and were prone to elevate along with disease progression. Furthermore, a gene analysis predicted that the target gene set of microRNAs might affect the regulation of TP53 via the epigenetic regulation of MECP2. Taken together, these 4 extracellular vesicle-associated microRNAs in circulation serve as a promising liquid biomarker to identify angiosarcoma patients and trace disease progression.

A promising role of noble metal NPs@MOFs in chondrosarcoma management

Chondrosarcoma, a challenging and malignant neoplasm originating from cartilage cells, poses significant diagnostic and therapeutic hurdles due to its resistance to conventional treatments and the complexity of its diagnosis. Noble metal nanoparticle-embedded metal-organic frameworks (NPs@MOFs) stand out as a novel approach for the diagnosis and treatment of chondrosarcoma. This review delves into the properties and applications of NPs@MOFs, focusing on their classification by noble metal type and their role in enhancing photothermal therapy (PTT), photodynamic therapy (PDT), targeted drug delivery and chondrosarcoma diagnosis. Despite promising in vitro and in vivo results, challenges such as understanding the mechanisms of action and clinical translation remain, and the therapeutic effect of PTT and PDT on deep chondrosarcoma seems unsatisfactory. Future exploration, such as combined therapy and multiple MOF therapy, could unlock the full potential of noble metal NPs@MOFs in revolutionizing chondrosarcoma management, offering insights into the prospect of these materials in chondrosarcoma management.

Extent of macroscopic vascular invasion predicts distant metastasis in primary leiomyosarcoma of the inferior vena cava

BACKGROUND

In retroperitoneal leiomyosarcoma (RP LMS), the predominant issue is distant metastasis (DM). We sought to determine variables associated with this outcome and disease-specific death (DSD).

METHODS

Data were retrospectively collected on patients with primary RP LMS treated at a high-volume center from 2002 to 2023. For inferior vena cava (IVC)-origin tumors, the extent of macroscopic vascular invasion was re-assessed on each resection specimen and correlated with preoperative cross-sectional imaging. Crude cumulative incidences were estimated for DM and DSD and univariable and multivariable models were performed.

RESULTS

Among 157 study patients, median tumor size was 11.0 cm and 96.2% of cases were intermediate or high grade. All patients underwent complete resection, 56.7% received chemotherapy (43.9% neoadjuvant) and 14.6% received radiation therapy. Only tumor size and grade and not site of tumor origin (e.g., IVC vs. other) were associated with DM and DSD (p < 0.05). Among 64 patients with IVC-origin tumors, a novel 3-tier classification was devised based on the level of intimal disruption, which was associated with both DM (p = 0.007) and DSD (0.002).

CONCLUSION

In primary RP LMS, only tumor size and grade are predictive of DM and DSD. In IVC-origin tumors, the extent of macroscopic vascular invasion is also strongly predictive of these outcomes.

Tumor Suppressor MicroRNAs in Clinical and Preclinical Trials for Neurological Disorders

Cancers and neurological disorders are two major types of diseases in humans. We developed the concept called the "Aberrant Cell Cycle Disease (ACCD)" due to the accumulating evidence that shows that two different diseases share the common mechanism of aberrant cell cycle re-entry. The aberrant cell cycle re-entry is manifested as kinase/oncoprotein activation and tumor suppressor (TS) inactivation, which are associated with both tumor growth in cancers and neuronal death in neurological disorders. Therefore, some cancer therapies (e.g., kinase/oncogene inhibition and TS elevation) can be leveraged for neurological treatments. MicroRNA (miR/miRNA) provides a new style of drug-target binding. For example, a single tumor suppressor miRNA (TS-miR/miRNA) can bind to and decrease tens of target kinases/oncogenes, producing much more robust efficacy to block cell cycle re-entry than inhibiting a single kinase/oncogene. In this review, we summarize the miRNAs that are altered in both cancers and neurological disorders, with an emphasis on miRNA drugs that have entered into clinical trials for neurological treatment.

Increased Expression of MiRNA-1 Contributes to Hypobaric Hypoxia-Induced Skeletal Muscle Loss

The present study aims to analyze the role of microRNA-1 in the regulation of skeletal muscle loss under hypobaric hypoxia (HH). Male Sprague Dawley rats (n = 10) weighing 230-250 g are divided into two groups, control and HH exposure for 7 days at 25 000 ft. After the hypoxia exposure, the animals are sacrificed and hindlimb skeletal muscles are excised for further analysis. Studies found the potential role of miR-1 (myomiR) as a biomarker under different atrophic conditions. Prolonged exposure to HH leads to enhanced expression of miR-1 in skeletal muscle as compared to unexposed controls. The Bioinformatics approach is used to identify the validated targets and the biological processes of miR-1. The target prediction tools identify PAX3 and HSP70 as major targets for miR-1. Exposure to HH significantly reduces PAX3 and HSP70 expression during 7 days of HH exposure, which further enhances the activity of FOXO3, MSTN, and ATROGIN known for the progression of skeletal muscle atrophy in relation to control rats. This study indicates the increased expressions of miR-1 and reduced expression of PAX3 and HSP70 lead to impaired myogenesis in skeletal muscle under HH. Further, enhanced expression of muscle degradation genes such as FOXO3, MSTN, and ATROGIN under HH exposure causes skeletal muscle protein loss.

Extracellular vesicle-associated microRNA signatures related to lymphovascular invasion in early-stage lung adenocarcinoma

Lymphovascular invasion (LVI) is a fundamental step toward the spread of cancer. Extracellular vesicles (EVs) promote cellular communication by shuttling cargo, such as microRNAs (miRNAs). However, whether EV-associated miRNAs serve as biomarkers for LVI remains unclear. This study aimed to identify EV-associated miRNAs related to LVI and validate the miRNA levels from patients with early-stage lung adenocarcinoma (LADC). Blood samples were collected from patients undergoing pulmonary resection for stage I LADC before surgery. The patients were classified into three groups according to the presence of LVI and postoperative recurrence. Serum-derived EVs in the derivation cohort were used for small RNA sequencing, while the selected LVI miRNA candidates were validated via real-time quantitative polymerase chain reaction using 44 patient and 16 healthy donor samples as the validation cohorts. Five miRNAs (miR-99b-3p, miR-26a-5p, miR-93-5p, miR-30d-5p, and miR-365b-3p) were assessed, and miR-30d-5p (p = 0.036) levels were significantly downregulated in the LVI-positive group. miR-30d-5p levels in healthy donors were lower than those in LADC patients. Patients with high miR-30d-5p levels had favorable survival compared to those with low miR-30d-5p levels. miR-30d-5p level in EVs may serve as a promising biomarker for detecting LVI in patients with early-stage LADC.

Exosomes in sarcoma: Prospects for clinical applications

Sarcoma is a group of rare and heterogeneous mesenchymal tumors, prone to late diagnosis and poor prognosis. Exosomes are cell-derived small extracellular vesicles found in most body fluids and contain nucleic acids, proteins, lipids, and other molecules. Qualitative and quantitative changes of exosomes and the contents are associated with sarcoma progression, exhibiting their potential as biomarkers. Exosomes possess the capacity of evading immune responses, bioactivity for trafficking, tumor tropism, and lesion residence. Thus, exosomes could be engineered as tumor-specific vehicles in drugs and RNA delivery systems. Exosomes might also serve as therapeutic targets in targeted therapy and immunotherapy and be involved in chemotherapy resistance. Here, we provide a comprehensive summary of exosome applications in liquid biopsy-based diagnosis and explore their implications in the delivery system, targeted therapy, and chemotherapy resistance of sarcoma. Moreover, challenges in exosome clinical applications are raised and some future research directions are proposed.

Emerging role of MyomiRs as biomarkers and therapeutic targets in skeletal muscle diseases

Several chronic diseases lead to skeletal muscle loss and a decline in physical performance. MicroRNAs (miRNAs) are small, noncoding RNAs, which have exhibited their role in the development and diseased state of the skeletal muscle. miRNA regulates gene expression by binding to the 3' untranslated region of its target mRNA. Due to the robust stability in biological fluids, miRNAs are ideal candidate as biomarker. These miRNAs provide a novel avenue in strengthening our awareness and knowledge about the factors governing skeletal muscle functions such as development, growth, metabolism, differentiation, and cell proliferation. It also helps in understanding the therapeutic strategies in improving or conserving skeletal muscle health. This review outlines the evidence regarding the present knowledge on the role miRNA as a potential biomarker in skeletal muscle diseases and their exploration might be a unique and potential therapeutic strategy for various skeletal muscle disorders.

Matrix-assisted laser desorption ionization mass spectrometry profiling of plasma exosomes evaluates osteosarcoma metastasis

Osteosarcoma is the most common primary sarcoma of bone among adolescents, often characterized by early lung metastasis resulting in high mortality. Recently, exosomes have been used in liquid biopsy to monitor tumors. Herein, we used matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to profile human plasma exosomes for the evaluation of osteosarcoma lung metastasis. Forty patients with osteosarcoma with (n = 20) or without (n = 20) lung metastasis as well as 12 heathy controls were recruited. Exosomes were isolated from human plasma for MALDI-TOF MS analysis. Multivariate statistical analyses were performed based on the MALDI-TOF mass spectra. The strategy can efficiently differentiate osteosarcomas from healthy controls and further discriminate osteosarcoma lung metastasis from non-lung metastasis. We identified seven exosomal proteins as potential biomarkers of osteosarcoma lung metastasis. The proposed method holds great promise to clinically diagnose osteosarcoma and monitor osteosarcoma lung metastasis.

Current perspectives on exosomes in the diagnosis and treatment of hepatocellular carcinoma (review)

The prognosis of hepatocellular carcinoma (HCC), a malignant tumor, is poor. Tumor recurrence and metastasis are the major challenges for the treatment of HCC. Various studies have demonstrated that exosomes, which are loaded with various biomolecules including nucleic acids, lipids, and proteins are involved in the recurrence and metastasis of HCC. Additionally, exosomes mediate various biological processes, such as immune response, cell apoptosis, angiogenesis, thrombosis, autophagy, and intercellular signal transduction. In cancer, exosomes regulate cancer cell differentiation, development, and drug resistance. Circular RNAs, microRNAs, and proteins in the exosomes can serve as early diagnostic and prognostic markers for HCC. As exosomes are characterized by low immunogenicity and high stability in the tissues and circulation, they can be used to deliver the drugs in cancer therapies.

Role of chemokines in hepatocellular carcinoma (Review)

Hepatocellular carcinoma (HCC) is a prevalent malignant tumor worldwide, with an unsatisfactory prognosis, although treatments are improving. One of the main challenges for the treatment of HCC is the prevention or management of recurrence and metastasis of HCC. It has been found that chemokines and their receptors serve a pivotal role in HCC progression. In the present review, the literature on the multifactorial roles of exosomes in HCC from PubMed, Cochrane library and Embase were obtained, with a specific focus on the functions and mechanisms of chemokines in HCC. To date, >50 chemokines have been found, which can be divided into four families: CXC, CX3C, CC and XC, according to the different positions of the conserved N‑terminal cysteine residues. Chemokines are involved in the inflammatory response, tumor immune response, proliferation, invasion and metastasis via modulation of various signaling pathways. Thus, chemokines and their receptors directly or indirectly shape the tumor cell microenvironment, and regulate the biological behavior of the tumor. In addition, the potential application of chemokines in chemotaxis of exosomes as drug vehicles is discussed. Exosomes containing chemokines or expressing receptors for chemokines may improve chemotaxis to HCC and may thus be exploited for targeted drug delivery.

Development and validation of an immune gene-set based prognostic signature for soft tissue sarcoma

Background

Sarcomas is a group of heterogeneous malignant tumors originated from mesenchymal tissue and different types of sarcomas have disparate outcomes. The present study aims to identify the prognostic value of immune-related genes (IRGs) in sarcoma and establish a prognostic signature based on IRGs.

Methods

We collected the expression profile and clinical information of 255 soft tissue sarcoma samples from The Cancer Genome Atlas (TCGA) database and 2498 IRGs from the ImmPort database. The LASSO algorithm and Cox regression analysis were used to identify the best candidate genes and construct a signature. The prognostic ability of the signature was evaluated by ROC curves and Kaplan-Meier survival curves and validated in an independent cohort. Besides, a nomogram based on the IRGs and independent prognostic clinical variables was developed.

Results

A total of 19 IRGs were incorporated into the signature. In the training cohort, the AUC values of signature at 1-, 2-, and 3-years were 0.938, 0.937 and 0.935, respectively. The Kaplan-Meier survival curve indicated that high-risk patients were significantly worse prognosis (P < 0.001). In the validation cohort, the AUC values of signature at 1-, 2-, and 3-years were 0.730, 0.717 and 0.647, respectively. The Kaplan-Meier survival curve also showed significant distinct survival outcome between two risk groups. Furthermore, a nomogram based on the signature and four prognostic variables showed great accuracy in whole sarcoma patients and subgroup analyses. More importantly, the results of the TF regulatory network and immune infiltration analysis revealed the potential molecular mechanism of IRGs.

Conclusions

In general, we identified and validated an IRG-based signature, which can be used as an independent prognostic signature in evaluating the prognosis of sarcoma patients and provide potential novel immunotherapy targets.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-07852-2.

Microfluidic detection of human diseases: From liquid biopsy to COVID-19 diagnosis

Microfluidic devices can be thought of as comprising interconnected miniaturized compartments performing multiple experimental tasks individually or in parallel in an integrated fashion. Due to its small size, portability, and low cost, attempts have been made to incorporate detection assays into microfluidic platforms for diseases such as cancer and infection. Some of these technologies have served as point-of-care and sample-to-answer devices. The methods for detecting biomarkers in different diseases usually share similar principles and can conveniently be adapted to cope with arising health challenges. The COVID-19 pandemic is one such challenge that is testing the performance of both our conventional and newly-developed disease diagnostic technologies. In this mini-review, we will first look at the progress made in the past few years in applying microfluidics for liquid biopsy and infectious disease detection. Following that, we will use the current pandemic as an example to discuss how such technological advancements can help in the current health challenge and better prepare us for future ones.

Comprehensive profiling of immune-related genes in soft tissue sarcoma patients

Background

Immune-related genes (IRGs) have been confirmed to have an important role in tumorigenesis and tumor microenvironment formation. Nevertheless, a systematic analysis of IRGs and their clinical significance in soft tissue sarcoma (STS) patients is lacking.

Methods

Gene expression files from The Cancer Genome Atlas (TCGA) database and Genotype-Tissue Expression (GTEx) were used to select differentially expressed genes (DEGs). Differentially expressed immune-related genes (DEIRGs) were determined by matching the DEG and ImmPort gene sets, which were evaluated by functional enrichment analysis. Unsupervised clustering of the identified DEIRGs was conducted, and associations with prognosis, the tumor microenvironment (TME), immune checkpoints, and immune cells were analyzed simultaneously. Two prognostic signatures, one for overall survival (OS) and one for progression free survival (PFS), were established and validated in an independent set. Finally, two transcription factor (TF)-IRG regulatory networks were constructed, and a crucial regulatory axis was validated.

Results

In total, 364 DEIRGs and four clusters were identified. OS, TME scores, five immune checkpoints, and 12 types of immune cells were found to be significantly different among the four clusters. The two prognostic signatures incorporating 20 DEIRGs showed favorable discrimination and were successfully validated. Two nomograms combining signature and clinical variables were generated. The C-indexes were 0.879 (95%CI 0.832 ~ 0.926) and 0.825 (95%CI 0.776 ~ 0.874) for the OS and PFS signatures, respectively. Finally, TF-IRG regulatory networks were established, and the MYH11-ADM regulatory axis was verified in three independent datasets.

Conclusion

This comprehensive analysis of the IRG landscape in soft tissue sarcoma revealed novel IRGs related to carcinogenesis and the immune microenvironment. These findings have implications for prognosis and therapeutic responses, which reveal novel potential prognostic biomarkers, promote precision medicine, and provide potential novel targets for immunotherapy.

MiR-101 promotes pain hypersensitivity in rats with chronic constriction injury via the MKP-1 mediated MAPK pathway

This study was performed to characterize the effect of microRNA‐101 (miR‐101) on the pain hypersensitivity in CCI rat models with the involvement of mitogen‐activated protein kinase phosphatase 1 (MKP‐1) in spinal cord microglial cells. The mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) in the developed CCI models were determined to assess the hypersensitivity of rats to mechanical stimulation and thermal pain. To assess inflammation, the levels of interleukin (IL)‐1β, IL‐6 and tumour necrosis factor‐α (TNF‐α) in the spinal dorsal horns of CCI rats and lipopolysaccharide (LPS)‐activated microglial cells were examined. miR‐101 and MKP‐1 gain‐ and loss‐of‐function experiments were conducted in in vivo and in vitro settings to examine the roles of miR‐101 and MKP‐1 in CCI hypersensitivity and inflammation. The results showed that miR‐101 was highly expressed in the spinal dorsal horn and microglial cells of CCI rat models. Furthermore, overexpression of miR‐101 promoted the pain hypersensitivity in CCI rat models by reducing MWT and TWL. The overexpression of miR‐101 also promoted inflammation in LPS‐exposed microglial cells, as indicated by increased levels of IL‐1β, IL‐6 and TNF‐α. MiR‐101 was shown to target MKP‐1, inhibiting its expression. Moreover, miR‐101 promoted pain hypersensitivity in CCI rat models by inhibiting MKP‐1 expression and activating the mitogen‐activated protein kinase (MAPK) signalling pathway. Taken together, miR‐101 could potentially promote hypersensitivity and inflammatory response of microglial cells and aggravate neuropathic pain in CCI rat models by inhibiting MKP‐1 in the MAPK signalling pathway.

The new horizon of liquid biopsy in sarcoma: the potential utility of circulating tumor nucleic acids

The diagnosis, treatment and prognosis of sarcoma are mainly dependent on tissue biopsy, which is limited in its ability to provide a panoramic view into the dynamics of tumor progression. In addition, effective biomarkers to monitor the progression and therapeutic response of sarcoma are lacking. Liquid biopsy, a recent technological breakthrough, has gained great attention in the last few decades. Nucleic acids (such as DNA, mRNAs, microRNAs, and long non-coding RNAs) that are released from tumors circulate in the blood of cancer patients and can be evaluated through liquid biopsy. Circulating tumor nucleic acids reflect the intertumoral and intratumoral heterogeneity, and thus liquid biopsy provides a noninvasive strategy to examine these molecules compared with traditional tissue biopsy. Over the past decade, a great deal of information on the potential utilization of circulating tumor nucleic acids in sarcoma screening, prognosis and therapy efficacy monitoring has emerged. Several specific gene mutations in sarcoma can be detected in peripheral blood samples from patients and can be found in circulating tumor DNA to monitor sarcoma. In addition, circulating tumor non-coding RNA may also be a promising biomarker in sarcoma. In this review, we discuss the clinical application of circulating tumor nucleic acids as blood-borne biomarkers in sarcoma.

The Optimal Outcome of Suppressing Ewing Sarcoma Growth in vivo With Biocompatible Bioengineered miR-34a-5p Prodrug

Being the second most common type of primary bone malignancy in children and adolescents, Ewing Sarcoma (ES) encounters the dilemma of low survival rate with a lack of effective treatments. As an emerging approach to combat cancer, RNA therapeutics may expand the range of druggable targets. Since the genome-derived oncolytic microRNA-34a (miR-34a) is down-regulated in ES, restoration of miR-34a-5p expression or function represents a new therapeutic strategy which is, however, limited to the use of chemically-engineered miRNA mimics. Very recently we have developed a novel bioengineering technology using a stable non-coding RNA carrier (nCAR) to achieve high-yield production of biocompatible miRNA prodrugs, which is a great addition to current tools for the assessment of RNA therapeutics. Herein, for the first time, we investigated the biochemical pharmacology of bioengineered miR-34a-5p prodrug (nCAR/miR-34a-5p) in the control of ES using human ES cells and xenograft mouse models. The bioengineered nCAR/miR-34a-5p was precisely processed to mature miR-34a-5p in ES cells and subsequently suppressed cell proliferation, attributable to the enhancement of apoptosis and induction of G2 cell cycle arrest through downregulation of SIRT-1, BCL-2 and CDK6 protein levels. Furthermore, systemic administration of nCAR/miR-34a-5p dramatically suppressed the ES xenograft tumor growth in vivo while showing biocompatibility. In addition, the antitumor effect of bioengineered nCAR/miR-34a-5p was associated with a lower degree of tumoral cell proliferation and greater extent of apoptosis. These findings demonstrate the efficacy of bioengineered miR-34a-5p prodrug for the treatment of ES and support the development of miRNA therapeutics using biocompatible bioengineered miRNA prodrugs.

Restoration of microRNA-197 expression suppresses oncogenicity in fibrosarcoma through negative regulation of RAN

MicroRNAs (miRNAs) act as crucial regulators of biological pathways/processes by reinforcing transcriptional programs and moderating transcripts. Emerging evidences have shown the involvement of dysregulated miRNAs in pathophysiology of human diseases including several cancer types. Recently, miR-197-3p has been reported to play different roles in different cancers; however, its role in fibrosarcoma, a highly aggressive and malignant soft tissue sarcoma originated from the mesenchymal tissues, has not yet been studied. Therefore, this study aims to investigate the possible regulatory roles of miR-197-3p in the oncogenicity of fibrosarcoma. For this, we initially performed qRT-PCR of miR-197-3p, which we found to be downregulated in HT1080 human fibrosarcoma cells compared with IMR90-tert normal fibroblast cells. Subsequently, we performed gain-of-function study by employing several methods such as MTT assay, clonogenic assay, wound healing, flow cytometry cell cycle analysis, and acridine orange staining after transfecting HT1080 cells with miR-197-3p mimic. From these assays, we observed that miR-197-3p significantly inhibits viability, colony forming, and migration ability as well as triggers G2/M phase cell cycle arrest and autophagy in fibrosarcoma cells. To understand the mechanism through which miRNA performs these functions, we predicted its targets using TargetScan and performed pathway enrichment analysis after screening them by their expression in fibrosarcoma. Among the enriched targets, we found RAN (ras-related nuclear protein) to be a crucial target through which miR-197-3p represses tumorigenesis by binding to its 3´ UTR, validated by luciferase reporter assay. The tumor suppressive role of the miRNA was further confirmed by transfecting its mimic in RAN-overexpressed cells which showed significant attenuation in tumorigenic effect of RAN in fibrosarcoma as seen in different assays. Taken together, our study unveiled that miR-197-3p acts as an oncosuppressor in fibrosarcoma through G2/M phase arrest and induction of autophagy, and raises the possibility to act as a novel therapeutic intervention for the malignancy.

MiR-155-5p exerts tumor-suppressing functions in Wilms tumor by targeting IGF2 via the PI3K signaling pathway

BACKGROUND

MicroRNA-155-5p (miR-155-5p) has been reported to play an oncogenic role in different human malignancies; however, its role in Wilms tumor (WT) remains unclear.

METHODS

Differentially expressed miRNAs (DE-miRNAs) and mRNAs (DEGs) in WT blood and tissues were identified by using miRNA microarray and RNA-sequencing. Bioinformatics prediction and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were used to predict the potential functions of DE-miRNAs. DE-miRNAs and DEGs in WT obtained from Gene Expression Omnibus (GEO) and Therapeutically Applicable Research to Generate Effective Treatments (TARGET) were identified by using the "edgeR" package. RT-qPCR was used to explore miR-155-5p and IGF2 expression and their clinical significance in WT specimens. A rhabdoid cell line (G401) and Ewing sarcoma cell line (SK-NEP-1) were used. Immunohistochemical staining, western blotting and dual-luciferase reporter assays were performed to study the mechanisms involved. The CCK-8, flow cytometry, wound healing and transwell assays were performed to identify the effects of miR-155-5p and IGF2 knockdown on cell proliferation, apoptosis, migration and invasion, respectively.

RESULTS

MiR-155-5p was downregulated in both blood and tissues from WT patients who did not receive chemotherapy before surgery but was upregulated in tissues from WT patients who had received chemotherapy before surgery. IGF2, PI3K, AKT and mTOR were found to be upregulated in WT tissues. Additionally, miR-155-5p and IGF2 were significantly correlated with TNM stage and lymphatic metastasis in WT patients. Molecular mechanism exploration indicated that IGF2 was downregulated by miR-155-5p via direct binding to its 3' untranslated region in cell lines. Furthermore, IGF2, PI3K, AKT and mTOR expression was inversely correlated with miR-155-5p expression, and PI3K, AKT and mTOR expression was positively correlated with IGF2 expression in cell culture. Functional studies demonstrated that miR-155-5p upregulation and IGF2 knockdown suppressed cell proliferation, migration and invasion and induced cell apoptosis. Moreover, the tumor-suppressing effects of miR-155-5p in cells were abrogated by miR-155-5p inhibitor treatment.

CONCLUSIONS

Taken together, these findings suggest that miR-155-5p functions as a tumor suppressor in WT through inactivating the PI3K/AKT/mTOR signaling pathway by directly targeting IGF2. Thus, miR-155-5p might be a novel therapeutic target for WT.

Exosome-Mediated MiR-155 Transfer Contributes to Hepatocellular Carcinoma Cell Proliferation by Targeting PTEN

BACKGROUND Most eukaryocytes release nano vesicles (30-120 nm), named exosomes, to various biological fluids such as blood, lymph, and milk. Hepatocellular carcinoma (HCC) is one of the tumors with the highest incidence rate in primary malignant carcinoma of the liver. However, the mechanism of HCC proliferation remains elusive. In this study, we aim to explore whether HCC cell-derived exosomes affect the proliferation of cancer cells. MATERIAL AND METHODS Exosomes were isolated from HCC cells by ultracentrifugation and were visualized the phenotype by transmission electron microscopy. Cell proliferation was detected by Cell Counting Kit-8 assays and EdU (5-ethynyl-2-deoxyuridine) incorporation assays. Dual-luciferase assays were performed to validate the paired correlation of miR-155 and 3'-UTR of PTEN (gene of phosphate and tension homology deleted on chromosome 10). A xenograft mice model was constructed to verify the effect of exosome-mediated miR-155 on cell proliferation in vivo. RESULTS Our finding showed that miR-155 was enriched in exosomes released from HCC cells. The exosome-containing miR-155 transferred into new HCC targeted cells and lead to the elevation of HCC cells' proliferation. Besides, the exosomal miR-155 directly bound to 3'-UTR of PTEN leading to the reduction of relevant targets in recipient liver cells. The knockdown of PTEN attenuated the proliferation of HCC cells treated with the exosomal miR-155. Moreover, nude-mouse experiment results revealed a promotional effect of the exosomal miR-155 on HCC cell-acquired xenografts. CONCLUSIONS Our study indicated that exosomal-specific miR-155 transfers to adjacent and/or more distant cells and stimulates the proliferation of HCC cells.

Exosomal miRNA-1231 derived from bone marrow mesenchymal stem cells inhibits the activity of pancreatic cancer

Pancreatic cancer (PC) is a highly malignant tumor with increased morbidity and mortality, which is difficult to diagnose and cure in the clinic. Through secreting exosomes containing biological molecules, including diverse RNAs and proteins, bone marrow mesenchymal stem cells (BM-MSCs) influence the immunity, inflammation, tumor environment, and cancer metastasis. In this study, low expression of miRNA-1231 (miR-1231) in exosomes derived from the peripheral blood was significantly correlated with the TNM stage of PC, suggesting the potential inhibitory effect of exosomal miR-1231 on PC occurrence and development. The proliferation, migration, invasion, and adhesion to the matrix of PC cells BxPC-3 and PANC-1 were negatively regulated by exosomes derived from the supernatants of BM-MSCs that transfected with miR-1231 oligonucleotides. Simultaneously, tumor growth in vivo was seriously restrained in BALB/C nude mice by tail vein injection with exosomes originated from BM-MSCs that transfected with miR-1231 mimics. The exosomes extracted from BM-MSCs with high level of miR-1231 inhibit the activity of PC, providing the potential application for developing new and efficient medicine for cancer therapy, especially for PC treatment. The exosomal miR-1231 of peripheral blood may also be a potential indicator for PC diagnosis in the future.

A four-mRNA model to improve the prediction of breast cancer prognosis

BACKGROUND

Breast cancer (BRCA) is the most prevalent cancer that threatens female health. A growing body of evidence has demonstrated the non-negligible effects of messenger RNAs (mRNAs) on biological processes involved in cancers; however, there is no definite conclusion regarding the role of mRNAs in predicting the prognosis of BRCA patients.

MATERIALS AND METHODS

We systematically screened the mRNA expression landscape and clinical data of samples from the Cancer Genome Atlas (TCGA). Univariate Cox analysis and robust likelihood-based survival analysis were conducted to identify key mRNAs associated with BRCA. Furthermore, risk scores based on multivariate Cox analysis divided the training set into high-risk and low-risk groups. ROC analysis determined the optimal cut-off point for patient classification of risk levels. The prognostic model was additionally validated in the testing set and complete dataset. Finally, we plotted the survival curves for the mRNAs used in our model.

RESULTS

We obtained the original expression data of 13,617 mRNAs from a total of 1088 samples. After comprehensive survival analysis, the four-mRNA (ACSL1, OTUD3, PKD1L2, and WISP1) prognosis risk assessment model was constructed. Furthermore, the area under cure (AUC) was 0.834, indicating that the model was meaningful and reasonable. In each dataset, analysis based on the four-mRNA signature risk score indicated that the survival status of the group with high risk score was worse than that of the group with low risk scores. Patients with strong mRNA expression of OTUD3, PKD1L2, and WISP1 tended to have good prognosis, whereas patients with high ACSL1 expression tended to have poor prognosis.

CONCLUSION

In summary, we constructed a four-mRNA prognosis risk assessment model for BRCA. The newly developed model offers more possibilities for assessing prognosis and guiding the selection of better treatment strategies for BRCA.