Exosome-mediated transfer of miR-1290 promotes cell proliferation and invasion in gastric cancer via NKD1

Emerging roles of exosomal circRNAs in non-small cell lung cancer

Despite the prevalence of non-small cell lung cancer (NSCLC) is high, the limited early detection and management of these tumors are restricted since there is an absence of reliable and precise diagnostic biomarkers and therapeutic targets. Exosomes transport functional molecules for facilitating intercellular communication, especially in the tumor microenvironment, indicating their potential as cancer biomarkers and therapeutic targets. Circular RNA (circRNA), a type of non-coding RNA possessing a covalently closed loop structure, substantial abundance, and tissue-specific expression patterns, is stably enriched in exosomes. In recent years, significant breakthroughs have been made in research on exosomal circRNA in NSCLC. This review briefly introduces the biogenesis, characterizations, and functions of circRNAs and exosomes, and systematically describes the biological functions and mechanisms of exosomal circRNAs in NSCLC. In addition, this study summarizes their role in the progression of NSCLC and discusses their clinical significance as biomarkers and therapeutic targets for NSCLC.

Clinical Impact of Exosome Chemistry in Cancer

As we progress into the 21st century, cancer stands as one of the most dreaded diseases. With approximately one in every four individuals facing a lifetime risk of developing cancer, cancer remains one of the most serious health challenges worldwide. Its multifaceted nature makes it an arduous and tricky problem to diagnose and treat. Over the years, researchers have explored plenty of approaches and avenues to improve cancer management. One notable strategy includes the study of extracellular vesicles (EVs) as potential biomarkers and therapeutics. Among these EVs, exosomes have emerged as particularly promising candidates due to their unique characteristic properties and functions. They are small membrane-bound vesicles secreted by cells carrying a cargo of biomolecules such as proteins, nucleic acids, and lipids. These vesicles play crucial roles in intercellular communication, facilitating the transfer of biological information between cell-to-cell communication. Exosomes transport cargoes such as DNA, RNA, proteins, and lipids involved in cellular reprogramming and promoting cancer. In this review, we explore the molecular composition of exosomes, significance of exosomes chemistry in cancer development, and its theranostic application as well as exosomes research complications and solutions.

Transcriptome analysis displays new molecular insights into the mechanisms of action of Mebendazole in gastric cancer cells

Gastric cancer (GC) is a common cancer worldwide. Therefore, searching for effective treatments is essential, and drug repositioning can be a promising strategy to find new potential drugs for GC therapy. For the first time, we sought to identify molecular alterations and validate new mechanisms related to Mebendazole (MBZ) treatment in GC cells through transcriptome analysis using microarray technology. Data revealed 1066 differentially expressed genes (DEGs), of which 345 (2.41 %) genes were upregulated, 721 (5.04 %) genes were downregulated, and 13,231 (92.54 %) genes remained unaltered after MBZ exposure. The overexpressed genes identified were CCL2, IL1A, and CDKN1A. In contrast, the H3C7, H3C11, and H1-5 were the top 3 underexpressed genes. Gene set enrichment analysis (GSEA) identified 8 pathways significantly overexpressed in the treated group (p < 0.05 and FDR<0.25). The validation of the expression of top desregulated genes by RT-qPCR confirmed the transcriptome results, where MBZ increased the CCL2, IL1A, and CDKN1A and reduced the H3C7, H3C11, and H1-5 transcript levels. Expression analysis in samples from TCGA databases correlated that the lower ILI1A and higher H3C11 and H1-5 gene expression are associated with decreased overall survival rates in patients with GC, indicating that MBZ treatment can improve the prognosis of patients. Thus, the data demonstrated that the drug MBZ alters the transcriptome of the AGP-01 lineage, mainly modulating the expression of histone proteins and inflammatory cytokines, indicating a possible epigenetic and immunological effect on tumor cells, these findings highlight new mechanisms of action related to MBZ treatment. Additional studies are still needed to better clarify the epigenetic and immune mechanism of MBZ in the therapy of GC.

Impact of brain organoid-derived sEVs on metastatic adaptation and invasion of breast carcinoma cells through a microphysiological system

Brain metastases are common in triple-negative breast cancer (TNBC), suggesting a complex process of cancer spread. The mechanisms enabling TNBC cell adaptation and proliferation in the brain remain unclear. Small extracellular vesicles (sEVs) play a crucial role in communication between breast carcinoma cells and the brain. However, the lack of relevant models hinders understanding of sEV-mediated communication. The present study assesses the impact of brain organoid-derived sEVs (BO-sEVs) on various behaviours of the MDA-MB-231 cell line, chosen as a representative of TNBC in a 3D microfluidic model. Our results demonstrate that 150-200 nm sEVs expressing CD63, CD9, and CD81 from brain organoid media decrease MDA-MB-231 cell proliferation, enhance their wound-healing capacity, alter their morphology into more mesenchymal mode, and increase their stemness. BO-sEVs led to heightened PD-L1, CD49f, and vimentin levels of expression in MDA-MB-231 cells, suggesting an amplified immunosuppressive, stem-like, and mesenchymal phenotype. Furthermore, these sEVs also induced the expression of neural markers such as GFAP in carcinoma cells. The cytokine antibody profiling array also showed that BO-sEVs enhanced the secretion of MCP-1, IL-6, and IL-8 by MDA-MB-231 cells. Moreover, sEVs significantly enhance the migration and invasion of carcinoma cells toward brain organoids in a 3D organoid-on-a-chip system. Our findings emphasize the potential significance of metastatic site-derived sEVs as pivotal mediators in carcinoma progression and adaptation to the brain microenvironment, thereby unveiling novel therapeutic avenues.

Extracellular Vesicle miRNAs in Diagnostics of Gastric Cancer

Gastric cancer (GC) poses a significant global health challenge because of its high mortality rate attributed to the late-stage diagnosis and lack of early symptoms. Early cancer diagnostics is crucial for improving the survival rates in GC patients, which emphasizes the importance of identifying GC markers for liquid biopsy. The review discusses a potential use of extracellular vesicle microRNAs (EV miRNAs) as biomarkers for the diagnostics and prognostics of GC. Methods. Original articles on the identification of EV miRNA as GC markers published in the Web of Science and Scopus indexed issues were selected from the PubMed and Google Scholar databases. We focused on the methodological aspects of EV analysis, including the choice of body fluid, methods for EV isolation and validation, and approaches for EV miRNA analysis. Conclusions. Out of 33 found articles, the majority of authors investigated blood-derived extracellular vesicles (EVs); only a few utilized EVs from other body fluids, including tissue-specific local biofluids (washing the tumor growth areas), which may be a promising source of EVs in the context of cancer diagnostics. GC-associated miRNAs identified in different studies using different methods of EV isolation and analysis varied considerably. However, three miRNAs (miR-10b, miR-21, and miR-92a) have been found in several independent studies and shown to be associated with GC in experimental models. Further studies are needed to determine the optimal miRNA marker panel. Another essential step necessary to improve the reliability and reproducibility of EV-based diagnostics is standardization of methodologies for EV handling and analysis of EV miRNA.

Research progress on molecular mechanism of pyroptosis caused by Helicobacter pylori in gastric cancer

Gastric cancer (GC) is a prevalent malignancy worldwide. Helicobacter pylori (H. pylori), a Gram-negative spiral bacterium, has the ability to colonize and persist in the human gastric mucosa. Persistent H. pylori infection has been identified as a major risk factor for ~80% of GC cases. The interplay between H. pylori pathogenicity, genetic background, and environmental factors collectively contribute to GC transformation. Eradicating H. pylori infection is beneficial in reducing the recurrence of gastric cancer and residual cancer. However, the underlying molecular mechanisms involved in GC remain incompletely understood. Additionally, H. pylori reshapes the immune microenvironment within the stomach which may compromise immunotherapy efficacy in infected individuals. Clinical eradication of H. pylori infection still faces numerous challenges. In this review, the authors summarize recent research progress on elucidating the molecular mechanisms underlying H. pylori infection in GC development. Notably, CagA protein-a carcinogenic virulence factor predominantly expressed by Asian strains of H. pylori-induces inflammation and excessive ROS production within gastric mucosa cells. Dysregulation of multiple pyroptosis signalling pathways can lead to malignant transformation of these cells. MiRNA-1290 plays a crucial role in GC initiation and progression while serving as an indicator for disease progression dynamics. Pyroptosis exhibits dual roles both promoting carcinogenesis and inhibiting tumour growth; thus it holds potential clinical applications for drug-resistant GC treatment strategies. Furthermore, pyroptosis may play a regulatory role within the immune system during gastric cancer development. Lastly, the authors provide an overview on current concepts regarding pyroptosis as well as insights into miRNA-1290's pathogenicity and clinical value within immune mechanisms associated with GC, aiming to serve as reference material for researchers.

Plasma exosomal miR-1290 and miR-29c-3p as diagnostic biomarkers for lung cancer

Background

Enhancing the diagnostic efficacy of early-stage lung cancer is crucial for improving prognosis. The objective of this study was to ascertain dependable exosomal miRNAs as biomarkers for the diagnosis of lung cancer.

Methods

Exosomal miRNA candidates were identified through miRNA sequencing and subsequently validated in various case-control sets using real-time quantitative reverse transcription-polymerase chain reaction (RT-qPCR). The correlation between the expression of exosomal miRNAs and the clinicopathological features of lung cancer was investigated. To assess the diagnostic efficacy of exosomal miRNAs for lung cancer, the receiver operating characteristic (ROC) curve analysis was conducted. The optimal cutoff value of exosomal miRNAs was determined in the testing cohort and subsequently confirmed in the validation cohort.

Results

The results showed that the expression of exosomal miR-1290 was significantly elevated, while that of miR-29c-3p was significantly decreased in the plasma of lung cancer patients, especially in those with early-stage lung cancer, compared to individuals with benign lung conditions (P < 0.01). Exosomal miR-1290 and miR-29c-3p demonstrated superior diagnostic efficacy compared to conventional tumor biomarkers in distinguishing between lung cancer and benign lung diseases, as evidenced by their respective area under the curve (AUC) values of 0.934 and 0.868. Furthermore, exosomal miR-1290 and miR-29c-3p exhibited higher diagnostic efficiency in early-stage lung cancer than traditional tumor markers, with AUC values of 0.947 and 0.895, respectively. Notably, both exosomal miR-1290 and miR-29c-3p displayed substantial discriminatory capacity in distinguishing between non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC), as indicated by their respective AUC values of 0.810 and 0.842.

Conclusions

The findings of this study provided evidence that exosomal miR-1290 and miR-29c-3p hold significant potential as biomarkers for the early detection of lung cancer, as well as for differentiating between NSCLC and SCLC.

NKD1 targeting PCM1 regulates the therapeutic effects of homoharringtonine on colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is the most common primary malignancy. Recently, antineoplastic attributes of homoharringtonine (HHT) have attracted lots of attention. This study investigated the molecular target and underlying mechanism of HHT in the CRC process by using a cellular and animal models.

METHODS

This study first detected the effects of HHT on the proliferation, cell cycle and apoptosis ability of CRC cells using CCK-8, Edu staining, flow cytometry and Western blotting assay. In vitro recovery experiment and in vivo tumorigenesis experiment were used to detect the targeted interaction between HHT and NKD1. After that, the downstream target and mechanism of action of HHT targeting NKD1 was determined using quantitative proteomics combined with co-immunoprecipitation/immunofluorescence assay.

RESULTS

HHT suppressed CRC cells proliferation by inducing cell cycle arrest and apoptosis in vitro and vivo. HHT inhibited NKD1 expression in a concentration and time dependent manner. NKD1 was overexpressed in CRC and its depletion enhanced the therapeutic sensitivity of HHT on CRC, which indicating that NKD1 plays an important role in the development of CRC as the drug delivery target of HHT. Furthermore, proteomic analysis revealed that PCM1 participated the process of NKD1-regulated cell proliferation and cell cycle. NKD1 interacted with PCM1 and promoted PCM1 degradation through the ubiquitin-proteasome pathway. The overexpression of PCM1 effectively reversed the inhibition of siNKD1 on cell cycle.

CONCLUSIONS

The present findings revealed that HHT blocked NKD1 expression to participate in inhibiting cell proliferation and inducing cell apoptosis, ultimately leading to obstruction of CRC development through NKD1/PCM1 dependent mechanism. Our research provide evidence for clinical application of NKD1-targeted therapy in improving HHT sensitivity for CRC treatment.

Roles of microRNAs and exosomes in Helicobacter pylori associated gastric cancer

Helicobacter pylori (H. pylori) is a common pathogen that infects more than half of the world's population. Its infection can not only lead to a variety of gastrointestinal diseases, such as chronic gastritis and gastric cancer (GC) but also be associated with many extra-gastrointestinal diseases. Exosomes, as a new intercellular information transmission medium, can carry biological signal molecules such as microRNAs (miRNAs) to regulate a variety of cellular physiological activities and are involved in multiple cancer processes. In this article, we provide a systematic review on the role of exosomal miRNAs in H. pylori-associated GC.

Exosomal microRNAs in breast cancer and their potential in diagnosis, prognosis and treatment prediction

The significance of exosomal microRNAs (EmiRs) in breast cancer (BC) diagnosis has been widely addressed over the past decades. However, little information is still available regarding these reliable biomarkers' impacts on BC early diagnosis, prognosis, and treatment outcome predictions, but their great potential in spotting BC early and their predictive essence in BC prognosis and treatment results are promising against this common cancer. The present review focuses on the most recent findings and advancements of EmiRs applications in BC early diagnosis and treatment prediction and identifies current helpful EmiRs that are widely used in this regard.

Characterization of miRNAs in Milk Small Extracellular Vesicles from Enzootic Bovine Leukosis Cattle

Enzootic bovine leukosis (EBL) is a B-cell lymphosarcoma caused by the bovine leukemia virus (BLV). Most BLV-infected cattle show no clinical signs and only some develop EBL. The pathogenesis of EBL remains unclear and there are no methods for predicting EBL before its onset. Previously, it was reported that miRNA profiles in milk small extracellular vesicles (sEVs) were affected in cattle in the late stage of BLV infection. It raised a possibility that miRNA profile in milk sEVs from EBL cattle could be also affected. To characterize the difference in milk of EBL cattle and healthy cattle, we examined the miRNA profiles in milk sEVs from four EBL and BLV-uninfected cattle each using microarray analysis. Among the detected miRNAs, three miRNAs—bta-miR-1246, hsa-miR-1290, and hsa-miR-424-5p—which were detectable using quantitative real-time PCR (qPCR) and are associated with cancers in humans—were selected as biomarker candidates for EBL. To evaluate the utility of these miRNAs as biomarkers for EBL, their levels were measured using milk that was freshly collected from 13 EBL and seven BLV-uninfected cattle. bta-miR-1246 and hsa-miR-424-5p, but not hsa-miR-1290, were detected using qPCR and their levels in milk sEVs from EBL cattle were significantly higher than those in BLV-uninfected cattle. bta-miR-1246 and hsa-miR-424-5p in sEVs may promote metastasis by targeting tumor suppressor genes, resulting in increased amounts in milk sEVs in EBL cattle. These results suggest that bta-miR-1246 and hsa-miR-424-5p levels in milk sEVs could serve as biomarkers for EBL.

The Oral Tumor Cell Exosome miR-10b Stimulates Cell Invasion and Relocation via AKT Signaling

An exosome derived from a cancer cell has been identified to regulate intercellular communication. However, the roles of oral cancer-derived ectodomains in tumor metastasis need to be investigated further. We investigated their roles in oral cancer cells in this paper. The enforcing effect on oral cancer cells was attributed primarily to miR-10b, a gene with a high level in exosomes that is transferred to recipient cells via oral cancer-derived exosomes. Exosomes were obtained by exosome isolation reagents. Also, exosome identification and analysis were performed by electron microscopy. The expression of miRNAs was analyzed by qRT-PCR. Protein expression was analyzed by Western blot. Also, invasion and migration experiments were performed to assay and evaluate the function of exosomal miR-10b. Exosome-mediated transfer of miR-10b promoted oral cancer cell behaviors, according to the findings. Finally, it was discovered that AKT signaling participates in regulating exosome-mediated invasion and migration of oral cancer cells and its activation reduced the inhibitory effect of miR-10b knockdown on oral cancer cells. Exosomal miR-10b derived from oral cancer cells enhances cell invasion and migration by activating AKT signaling.

Circular_0086414 induces SPARC like 1 (SPARCL1) production to inhibit esophageal cancer cell proliferation, invasion and glycolysis and induce cell apoptosis by sponging miR-1290

Circular RNA (circRNA) plays an important role in cancer progression. Here, we investigated the function of circ_0086414 in the malignant progression of esophageal cancer (EC). RNA expression of circ_0086414, microRNA-1290 (miR-1290), and SPARC like 1 (SPARCL1) was detected by quantitative real-time polymerase chain reaction. The protein levels of N-cadherin, E-cadherin, and SPARCL1 were checked by Western blotting analysis. Cell proliferation was investigated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), 5-Ethynyl-29-deoxyuridine (EdU), and cell colony formation assays. Cell invasion and apoptosis were analyzed by transwell invasion assay and flow cytometry analysis, respectively. Glycolysis was evaluated by analyzing glucose consumption and lactate production. In an xenograft mouse model, the effect of circ_0086414 on tumor tumorigenesis was investigated. The interactions among circ_0086414, miR-1290, and SPARCL1 were identified by dual-luciferase reporter and RNA pull-down assays. Results showed that circ_0086414 and SPARCL1 expression were significantly downregulated, while miR-1290 was upregulated in EC tissues and cells. EC patients with low circ_0086414 expression had a poor prognosis. Increasing circ_0086414 expression led to decreased EC cell proliferation, invasion and glycolysis and increased cell apoptosis, accompanied by a decrease of N-cadherin expression and an increase of E-cadherin expression. Also, the enforced expression of circ_0086414 delayed tumor tumorigenesis. Besides, circ_0086414 acted as a miR-1290 sponge and regulated EC cell processes by binding to the miRNA. MiR-1290 also participated in EC malignant progression through SPARCL1. Further, circ_0086414 stimulated SPARCL1 production by negatively regulating miR-1290. Thus, circ_0086414 inhibited EC cell malignancy through the miR-1290/SPARCL1 pathway, providing a reliable target for the therapy of EC.

Gastric cancer-derived exosomal miR-135b-5p impairs the function of Vγ9Vδ2 T cells by targeting specificity protein 1

Recent studies have shown that tumor-derived exosomes participate in the communication between tumor cells and their microenvironment and mediate malignant biological behaviors including immune escape. In this study, we found that gastric cancer (GC) cell-derived exosomes could be effectively uptaken by Vγ9Vδ2 T cells, decrease the cell viability of Vγ9Vδ2 T cells, induce apoptosis, and reduce the production of cytotoxic cytokines IFN-γ and TNF-α. Furthermore, we demonstrated that exosomal miR-135b-5p was delivered into Vγ9Vδ2 T cells. Exosomal miR-135b-5p impaired the function of Vγ9Vδ2 T cells by targeting specificity protein 1 (SP1). More importantly, blocking the SP1 function by Plicamycin, an SP1 inhibitor, abolished the effect of stable miR-135b-5p knockdown GC cell-derived exosomes on Vγ9Vδ2 T cell function. Collectively, our results suggest that GC cell-derived exosomes impair the function of Vγ9Vδ2 T cells via miR-135b-5p/SP1 pathway, and targeting exosomal miR-135b-5p/SP1 axis may improve the efficiency of GC immunotherapy based on Vγ9Vδ2 T cells.

Extracellular Vesicles Promote the Formation of Pre-Metastasis Niche in Gastric Cancer

Globally, gastric cancer (GC) ranks fourth in the incidence of malignant tumors. The early clinical manifestations of GC lack specificity. Most patients are already at an advanced stage when they are first diagnosed, and their late progression is mainly due to peritoneal metastasis. A pre-metastatic microenvironment is formed, before the macroscopic tumor metastasis. Extracellular vesicles (EVs) are nanovesicles released by cells into body fluids. Recent studies have shown that EVs can affect the tumor microenvironment by carrying cargos to participate in cell-to-cell communication. EVs derived from GC cells mediate the regulation of the pre-metastasis niche and act as a coordinator between tumor cells and normal stroma, immune cells, inflammatory cells, and tumor fibroblasts to promote tumor growth and metastasis. This review highlights the regulatory role of EVs in the pre-metastatic niche of GC and mulls EVs as a potential biomarker for liquid biopsy.

An Insight into miR-1290: An Oncogenic miRNA with Diagnostic Potential

For more than two decades, the view of the roles of non-coding RNAs (ncRNAs) has been radically changing. These RNA molecules that are transcribed from our genome do not have the capacity to encode proteins, but are critical regulators of gene expression at different levels. Our knowledge is constantly enriched by new reports revealing the role of these new molecular players in the development of many pathological conditions, including cancer. One of the ncRNA classes includes short RNA molecules called microRNAs (miRNAs), which are involved in the post-transcriptional control of gene expression affecting various cellular processes. The aberrant expression of miRNAs with oncogenic and tumor-suppressive function is associated with cancer initiation, promotion, malignant transformation, progression and metastasis. Oncogenic miRNAs, also known as oncomirs, mediate the downregulation of tumor-suppressor genes and their expression is upregulated in cancer. Nowadays, miRNAs show promising application in diagnosis, prediction, disease monitoring and therapy response. Our review presents a current view of the oncogenic role of miR-1290 with emphasis on its properties as a cancer biomarker in clinical medicine.

A Review on the Role of miR-1290 in Cell Proliferation, Apoptosis and Invasion

MicroRNAs (miRNAs) have been shown to affect expression of several genes contributing in important biological processes. miR-1290 a member of this family with crucial roles in the carcinogenesis. This miRNA is transcribed from MIR1290 gene on chromosome 1p36.13. This miRNA has interactions with a number of mRNA coding genes as well as non-coding RNAs SOCS4, GSK3, BCL2, CCNG2, KIF13B, INPP4B, hMSH2, KIF13B, NKD1, FOXA1, IGFBP3, CCAT1, FOXA1, NAT1, SMEK1, SCAI, ZNF667-AS1, ABLIM1, Circ_0000629 and CDC73. miR-1290 can also regulate activity of JAK/STAT3, PI3K/AKT, Wnt/β-catenin and NF-κB molecular pathways. Most evidence indicates the oncogenic roles of miR-1290, yet controversial evidence also exists. In the present review, we describe the results of in vitro, animal and human investigations about the impact of miR-1290 in the development of malignancies.

The potential role of miR-1290 in cancer progression, diagnosis, prognosis, and treatment: An oncomiR or onco-suppressor microRNA?

Cancer is one of the leading causes of death in humans because of the lack of early diagnosis, distant metastases, and the resistance to adjuvant therapies, including chemotherapy and radiotherapy. In addition to playing an essential role in tumor progression and development, microRNAs (miRNAs) can be used as a robust biomarker in the early detection of cancer. MiR-1290 was discovered for the first time in human embryonic stem cells, and under typical physiological situations, plays an essential role in neuronal differentiation and neural stem cell proliferation. Its coding sequence is located at the 1p36.13 regions in the first intron of the aldehyde dehydrogenase 4 gene member A1. miR-1290 is out of control in many cancers such as breast cancer, colorectal cancer, esophageal squamous cell carcinoma, gastric cancer, lung cancer, pancreatic cancer, and plays a vital role in their development. Therefore, it is suggested that miR-1290 can be considered as a potential diagnostic and therapeutic target in many cancers. In addition to the importance of miR-1290 in the noninvasive diagnosis of various cancers, this systematic review study discussed the role of miR-1290 in altering the expression of different genes involved in cancer development and chemo-radiation resistance. Moreover, it considered the regulatory effect of natural products on miR-1290 expression and the interaction of lncRNAs by miR-1290.

Roles and mechanisms of exosomal non-coding RNAs in human health and diseases

Exosomes play a role as mediators of cell-to-cell communication, thus exhibiting pleiotropic activities to homeostasis regulation. Exosomal non-coding RNAs (ncRNAs), mainly microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), are closely related to a variety of biological and functional aspects of human health. When the exosomal ncRNAs undergo tissue-specific changes due to diverse internal or external disorders, they can cause tissue dysfunction, aging, and diseases. In this review, we comprehensively discuss the underlying regulatory mechanisms of exosomes in human diseases. In addition, we explore the current knowledge on the roles of exosomal miRNAs, lncRNAs, and circRNAs in human health and diseases, including cancers, metabolic diseases, neurodegenerative diseases, cardiovascular diseases, autoimmune diseases, and infectious diseases, to determine their potential implication in biomarker identification and therapeutic exploration.

Identification of colon tumor marker NKD1 via integrated bioinformatics analysis and experimental validation

Background

Colorectal cancer is an important death‐related disease in the worldwide. However, specific colon cancer tumor markers currently used for diagnosis and treatment are few. The purpose of this study is to screen the potential colon cancer markers by bioinformatics and verify the results with experiments.

Methods

Gene expression data were downloaded from two different databases: TCGA database and GEO datasets, which were then analyzed by two different methods (difference analysis and WGCNA method). Venn and PPI analysis obtained the potential core genes, which were then performed the GO enrichment and KEGG pathway analysis. Expressions levels of NKD1 in colon carcinoma tissues were further confirmed by immunohistochemical staining and western blot assays. Moreover, the function was measured by MTT, clone formation, and tumor transplantation experiments. Importantly, co‐immunoprecipitation, immunofluorescence, and protein stability assays were further performed to explore the underlying mechanism of NKD1 promoting cell proliferation.

Results

Nine potential core genes highly expressed in colon cancer samples were screened out by bioinformatics analysis. NKD1, one of the hub genes, highly expressed in the colon carcinoma tissues could enhance the proliferation of colon cancer cells. Mechanism research demonstrated that NKD1 was essential for the combination between Wnt signalosome (DVL) and β‐catenin, and that NKD1 knockout remarkably decreased the β‐catenin expression. Immunofluorescence assays further implied that NKD1 knockout significantly inhibited β‐catenin nuclear accumulation. Importantly, the stability of β‐catenin proteins was maintained by NKD1 in the colon cancer cells.

Conclusion

We believe that NKD1 well expressed in the colorectal carcinoma tissues can enhance the proliferation of colon cancer cells. Furthermore, the functions that NKD1 may have in colon cancer cells should be different from that NKD1 has played in the zebrafish. Thus, NKD1 could be a specific colorectal cancer marker.

Sevoflurane blocks glioma malignant development by upregulating circRELN through circRELN-mediated miR-1290/RORA axis

Background

Sevoflurane (Sev) has been reported to inhibit cancer development, and sevoflurane treatment in cancers is implicated with the deregulation of specific non-coding RNAs (ncRNAs). This study aimed to investigate the relationship between sevoflurane and circular RNA reelin (circRELN) in glioma.

Methods

The expression of circRELN, microRNA-1290 (miR-1290) and RAR-related orphan receptor A (RORA) was measured by quantitative real-time PCR (qPCR). Cell proliferative capacity was assessed by cell counting kit-8 (CCK-8) and colony formation assays. Cell apoptosis and cell cycle distribution were monitored by flow cytometry assay. Cell migration was assessed by wound healing assay and transwell assay, and cell invasion was assessed by transwell assay. The protein levels of matrix metalloproteinase-2 (MMP2), MMP9 and RORA were quantified by western blot. Tumor growth in vivo was assessed by Xenograft models. The binding relationship between miR-1290 and circRELN or RORA was verified by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay.

Results

We found that circRELN expression was declined in glioma tissues and cells, while Sev treatment enhanced circRELN expression. In function, Sev notably inhibited glioma cell proliferation, migration and invasion and promoted apoptosis and cell cycle arrest, while circRELN knockdown reversed these effects. MiR-1290 served as a target of circRELN, and glioma cell malignant phenotypes recovered by circRELN knockdown were partly repressed by miR-1290 deficiency. In addition, RORA was a target of miR-1290, and glioma cell malignant phenotypes promoted by miR-1290 restoration were partly blocked by RORA overexpression. CircRELN regulated RORA expression by targeting miR-1290. In Xenograft models, Sev inhibited tumor growth by upregulating circRELN.

Conclusion

Sev blocked the progression of glioma by increasing circRELN expression, and circRELN played roles in glioma partly by regulating the miR-1290/RORA network.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-021-01427-1.

Circulating MiR-1290 as a potential diagnostic and disease monitoring biomarker of human gastrointestinal tumors

Background

Gastrointestinal tumors are a leading cause of mortality worldwide. As shown in our previous study, miR-1290 is overexpressed in colorectal cancer (CRC) and promotes tumor progression. We therefore aimed to explore the potential of circulating miR-1290 as a biomarker for gastrointestinal cancer.

Methods

A serum miRNA sequencing analysis was performed. Then, circulating miRNA detection technologies were established. The expression of miR-1290 was analyzed in gastrointestinal tumor cell lines and culture supernatants. Expression levels of circulating miR-1290 in clinical samples were examined. Associations between miR-1290 expression and clinicopathologic characteristics were analyzed. Xenograft models were generated to assess the fluctuation in serum miR-1290 levels during disease progression.

Results

Through miRNA sequencing, we identified that miR-1290 was overexpressed in serum samples from patients with CRC. We confirmed that human gastrointestinal tumor cells express and secrete miR-1290. The circulating miR-1290 levels was up-regulated in patients with pancreatic cancer (PC) (p < 0.01), CRC (p < 0.05), and gastric cancer (GC) (p < 0.01). High miR-1290 expression levels were associated with tumor size, lymphatic invasion, vascular invasion, distant metastasis, tumor differentiation and AJCC stage in patients with PC and CRC. The area under the curve (AUC) was 0.8857 in patients with PC, with 60.9% sensitivity and 90.0% specificity. The AUC was 0.7852 in patients with CRC, with 42.0% sensitivity and 90.0% specificity. In patients with GC, the AUC was 0.6576, with 26.0% sensitivity and 90.0% specificity. The in vivo model verified that the circulating miR-1290 level was significantly increased after tumor formation and decreased after drug treatment.

Conclusions

Our findings indicate that circulating miR-1290 is a potential biomarker for gastrointestinal cancer diagnosis and monitoring.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08729-0.

Role of Exosomal Non-coding RNAs in Gastric Cancer: Biological Functions and Potential Clinical Applications

Gastric cancer (GC) is one of the most common fatal cancers worldwide. The communication between GC and other cells in the GC microenvironment directly affects GC progression. Recently, exosomes have been revealed as new players in intercellular communication. They play an important role in human health and diseases, including cancer, owing to their ability to carry various bioactive molecules, including non-coding RNAs (ncRNAs). NcRNAs, including micro RNAs, long non-coding RNAs, and circular RNAs, play a significant role in various pathophysiological processes, especially cancer. Increasing evidence has shown that exosomal ncRNAs are involved in the regulation of tumor proliferation, invasion, metastasis, angiogenesis, immune regulation, and treatment resistance in GC. In addition, exosomal ncRNAs have promising potential as diagnostic and prognostic markers for GC. Considering the biocompatibility of exosomes, they can also be used as biological carriers for targeted therapy. This review summarizes the current research progress on exosomal ncRNAs in gastric cancer, focusing on their biological role in GC and their potential as new biomarkers for GC and therapeutics. Our review provides insight into the mechanisms involved in GC progression, which may provide a new point cut for the discovery of new diagnostic markers and therapeutic strategies.

Tumor-derived extracellular vesicles containing microRNA-1290 promote immune escape of cancer cells through the Grhl2/ZEB1/PD-L1 axis in gastric cancer

Gastric cancer (GC) is a highly prevalent malignancy featured by dismal oncological outcomes. Accumulating pieces of evidence have consensus over the therapeutic significance of extracellular vesicles (EVs) and its role in carcinogenesis. Here, we planned to uncover EVs' role in GC by shuttling microRNA-1290 (miR-1290) and to identify the possible molecular mechanism associated with Grhl2, PD-L1, and ZEB1. Grhl2 was under-expressed in GC tissues, exhibiting a negative correlation with PD-L1 expression. In addition, Grhl2 promoted T cell proliferation by down-regulating PD-L1 via inhibiting ZEB1, while miR-1290 was found to negatively regulate Grhl2. EVs were also isolated from GC cells or normal gastric epithelial cells and identified with the presence of EV markers. miR-1290 expression was determined to be enriched in the EVs derived from GC cells and observed to promote the suppressive action of GC cells on T cell activation by up-regulating PD-L1 via the Grhl2/ZEB1 pathway in the co-culture system of GC cells with or without treatment of EVs with T cells. Moreover, we also developed a mouse model of GC and injected the EVs derived from miR-1290-inhibitor-treated GC cells into the tumor-bearing mice for further validation of mechanism in vivo. Intriguingly, the pivotal role of EVs-shuttled miR-1290 as an oncomiR was demonstrated in vivo. Collectively, we found that miR-1290 in EVs secreted from GC cells contributed to immune escape through the Grhl2/ZEB1/PD-L1 axis.

The role and application of small extracellular vesicles in gastric cancer

Gastric cancer (GC) is a common tumour that affects humans worldwide, is highly malignant and has a poor prognosis. Small extracellular vesicles (sEVs), especially exosomes, are nanoscale vesicles released by various cells that deliver bioactive molecules to recipient cells, affecting their biological characteristics, changing the tumour microenvironment and producing long-distance effects. In recent years, many studies have clarified the mechanisms by which sEVs function with regard to the initiation, progression, angiogenesis, metastasis and chemoresistance of GC. These molecules can function as mediators of cell-cell communication in the tumour microenvironment and might affect the efficacy of immunotherapy. Due to their unique physiochemical characteristics, sEVs show potential as effective antitumour vaccines as well as drug carriers. In this review, we summarize the roles of sEVs in GC and highlight the clinical application prospects in the future.

Exosomal miR-130a-3p promotes the progression of differentiated thyroid cancer by targeting insulin-like growth factor 1

The aim of the present study was to determine the expression and diagnostic value of exosomal miR-130a-3p in the serum of patients with differentiated thyroid cancer (DTC). Exosomes were isolated from the serum of patients with DTC and were identified using transmission electron microscopy. A novel exosomal miRNA, miR-130a-3p, was found to be significantly decreased in the serum of patients with DTC compared with those with benign thyroid tumors and healthy controls. Further study revealed that exosomal miR-130a-3p was correlated with the malignant characteristics of DTC, including tumor diameter, lymph node metastasis (LNM) and higher TNM stage. Receiver operating characteristic curve analysis demonstrated that the area under the curve of exosomal miR-130a-3p was better compared with that of TgAb and Tg in patients with DTC. More importantly, the combined use of exosomal miR-130a-3p, TgAb and Tg significantly enhanced the sensitivity and specificity, indicating that exosomal miR-130a-3p is a sensitive biomarker for DTC. A dual luciferase reporter assay indicated that insulin-like growth factor (IGF)-1 was a target gene of miR-130a-3p. Pearson's correlation analysis revealed a negative correlation between serum IGF-1 and serum exosomal miR-130a-3p levels. More importantly, exosomes from patients with DTC increased the expression of IGF-1 and p-PI3K/p-AKT, but these effects were abolished by siRNA targeting IGF-1 in TPC-1 cells. Taken together, the findings of the present study indicated that reduced exosomal miR-130a-3p levels were associated with the risk of DTC and may be used as a biomarker for the diagnosis of DTC.

Clinical crosstalk between microRNAs and gastric cancer (Review)

Globally, there were over 1 million new gastric cancer (GC) patients in 2018 and GC has become the sixth most common cancer worldwide. GC caused 783,000 deaths worldwide in 2018, making it the third most deadly cancer type. miRNAs are short (~22 nucleotides in length) non‑coding RNA molecules, which can regulate gene expression passively at a post‑transcriptional level. There are more and more in‑depth studies on miRNAs. There are numerous conclusive evidences that there is an inseparable link between miRNAs and GC. miRNAs can affect the entire process of GC, including the oncogenesis, development, diagnosis, treatment and prognosis of GC. Although many miRNAs have been linked to GC, few can be applied to clinical practice. This review takes the clinical changes of GC as a clue and summarizes the miRNAs related to GC that have confirmed the mechanism of action in the past three years. Through in‑depth study and understanding of the mechanism of those miRNAs, we predict their possible clinical uses, and suggest some new insights to overcome GC.

Exosomal miR-122-5p inhibits tumorigenicity of gastric cancer by downregulating GIT1

BACKGROUND

microRNAs (miRNAs) are non-coding RNAs with important roles in the progression of human cancers, including gastric cancer. Exosomes are extracellular vesicles, which could transfer numerous noncoding RNAs, such as miRNAs. Here, in our study, we intended to investigate the role of exosomal miR-122-5p in gastric cancer progression.

METHODS

Exosomes were isolated utilizing commercial kit or ultracentrifugation. Biomarkers of exosomes or epithelia-mesenchymal transition (EMT) were monitored by western blot. Expression levels of miR-122-5p and G-protein-coupled receptor kinase interacting protein-1 (GIT1) were evaluated by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) or western blot. Cell proliferation and apoptosis were assessed by colony formation assay, methyl thiazolyl tetrazolium assay and flow cytometry. Cell metastasis was evaluated via Transwell assay. The interaction between miR-122-5p and GIT1 was validated by dual-luciferase reporter assay. Furthermore, tumor growth in vivo was detected by xenograft assay.

RESULTS

Exosomes were successfully isolated. MiR-122-5p was downregulated in exosomes derived from the serum of gastric cancer patients. Exosomal miR-122-5p could hinder gastric cancer cell proliferation and metastasis in vitro and tumor growth in vivo. Knockdown of GIT1 also inhibited gastric cancer cell proliferation and metastasis. Exosomal miR-122-5p targeted GIT1 to alter cellular behaviors of gastric cancer cells.

CONCLUSION

Exosomal miR-122-5p suppressed gastric cancer progression by targeting GIT1.

MiR-1290 promotes myoblast differentiation and protects against myotube atrophy via Akt/p70/FoxO3 pathway regulation

BACKGROUND

Sarcopenia is a common skeletal disease related to myogenic disorders and muscle atrophy. Current clinical management has limited effectiveness. We sought to investigate the role of miR-1290 in myoblast differentiation and muscle atrophy.

METHODS

By transfecting miR-1290 into C2C12 cells, we investigated whether miR-1290 regulates myogenesis and myotube atrophy via AKT/P70 signaling pathway. MHC staining was performed to assess myoblast differentiation. Differentiation-related MHC, Myod, and Myog protein levels, and atrophy-related MuRF1 and atrogin-1 were explored by western blot. An LPS-induced muscle atrophy rat model was developed. RT-PCR was conducted to analyze miR-1290 serum levels in muscle atrophy patients and normal controls (NCs).

RESULTS

The miR-1290 transfection increased MHC-positive cells and MHC, Myod, and Myog protein levels in the miR-1290 transfection group, demonstrating that miR-1290 promoted C2C12 myoblast differentiation. Myotube diameter in the miR-1290 transfection group was higher than in the TNF-α-induced model group. Western blot analysis showed decreased MuRF1 and atrogin-1 levels in the miR-1290 transfection group compared with the model group, demonstrating that miR-1290 protected against myoblast cellular atrophy. Luciferase assay and western blot analysis showed that miR-1290 regulation was likely caused by AKT/p70/FOXO3 phosphorylation activation. In the LPS-induced muscle atrophy rat model, miR-1290 mimics ameliorated gastrocnemius muscle loss and increased muscle fiber cross-sectional area. Clinically, miR-1290 serum level was significantly decreased in muscle atrophy patients.

CONCLUSIONS

We found that miR-1290 enhances myoblast differentiation and inhibits myotube atrophy through Akt/p70/FoxO3 signaling in vitro and in vivo. In addition, miR-1290 may be a potential therapeutic target for sarcopenia treatment.

Exosomal NNMT from peritoneum lavage fluid promotes peritoneal metastasis in gastric cancer

Peritoneal metastasis (PM) is the major cause of recurrence in patients with gastric cancer (GC) and is associated with poor prognosis. The oncogenic role of Nicotinamide N-methyltransferase (NNMT) in GC has been reported, but the role of secreted NNMT that is transported by exosomes remains unknown. In this study, exosomes were isolated from GC patients with or without PM and from GC cell line, including GC-114, GC-026, MKN45, and SNU-16 cells. The contents of NNMT were significantly enhanced in exosomes isolated from GC patients with PM compared with those from GC patients without PM. Furthermore, the levels of NNMT were significantly enhanced in exosomes from GC cell lines relative to those from normal human gastric epithelial cell line GES-1 cells. These data indicate that NNMT may be involved in intercellular communication for peritoneal dissemination. Moreover, colocalization of GC-derived exosomal NNMT was found in human peritoneal mesothelial cell line HMrSV5 cells. Additionally, relative to GES-1 exosomes, SNU-16 exosomes significantly activated TGF-β/smad2 signaling in HMrSV5 cells. However, when NNMT was silenced, the activation of TGF-β/smad2 by SNU-16 exosomes was abolished in HMrSV5 cells. We propose that NNMT-containing exosomes derived from GC cells could promote peritoneal metastasis via TGF-β/smad2 signaling.

The Significance of Exosomal RNAs in the Development, Diagnosis, and Treatment of Gastric Cancer

Gastric cancer (GC) is one of the most common malignancies in the world. Exosomes, a subset of extracellular vesicles with an average diameter of 100 nm, contain and transfer a variety of functional macromolecules such as proteins, lipids, and nucleic acids. A large number of studies indicated that exosomes can play a significant role in the initiation and development of GC via facilitating intercellular communication between gastric cancer cells and microenvironment. Exosomal RNAs, one of the key functional cargos, are involved in the pathogenesis, development, and metastasis of GC. In addition, recent studies elucidated that exosomal RNAs may serve as diagnostic and prognostic biomarkers or therapeutic targets for GC. In this review, we summarized the function of exosomal RNA in the tumorigenesis, progression, diagnosis, and treatment of GC, which may further unveil the functions of exosome and promote the potentially diagnostic and therapeutic application of exosomes in GC.

Extracellular vesicle derived miR-544 downregulates expression of tumor suppressor promyelocytic leukemia zinc finger resulting in increased peritoneal metastasis in gastric cancer

Peritoneal metastasis (PM) is the main cause of poor prognosis in patients with advanced gastric cancer (GC). Increasing evidence has suggested that cancer-associated EVs in body fluids may assist in the diagnosis and treatment of GC. Here, we investigated the role of GC-derived EVs in PM development. Our results demonstrate that expression of the tumor suppressor promyelocytic leukemia zinc finger (PLZF) is decreased in GC tissues and PM lesions from GC patients. PLZF suppression promoted migration and invasion of peritoneal mesothelial HMrSV5 cells, while PLZF overexpression suppressed HMrSV5 cell migration and invasion. Microarray analysis revealed significantly upregulated expression of several miRNAs in EVs isolated from GC patients with PM, including miR-544. The increased miR-544 expression was confirmed in GC tissues and PM-derived EVs. Transfection with miR-544 reduced PLZF expression in HMrSV5 cells, while miR-544 inhibition increased PLZF expression. Incubation of GC cells with peritoneal mesothelial HMrSV5 cells showed that miR-544 could be transferred from GC-derived EVs to peritoneal cells, where it suppressed the PLZF expression. These findings indicate that EV-mediated transfer of miR-544 decreases the PLZF expression in PM lesions, which suggests miR-544 could potentially serve as a diagnostic biomarker and therapeutic target for treatment of GC patients.

Inactivation of Pancreatic Stellate Cells by Exendin-4 Inhibits the Migration and Invasion of Pancreatic Cancer Cells

Background

Pancreatic stellate cells (PSCs) are precursor cells of cancer-associated fibroblasts that promote tumor proliferation, invasion, and metastasis. The glucagon-like peptide-1 receptor agonist exendin-4 has been reported to exhibit anticancer effects against several tumor cells; however, the function and mechanism underlying the effects of exendin-4 on pancreatic cancer cells remain unclear.

Methods

Gene expression levels were determined using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot assay. Cell viability, migration and invasion were assessed using the cell counting kit-8 (CCK-8), wound healing, and transwell assays, respectively. A xenografted tumor model was established in mouse to evaluate the effects of exendin-4 in vivo.

Results

Exendin-4 treatment led to the inactivation of PSCs and suppressed their proliferation and migration. Moreover, we also found that exendin-4 attenuated NF-κB-dependent SDF-1 secretion. Furthermore, pancreatic cancer cells incubated with conditioned medium obtained from exendin-4-treated PSCs showed a decreased ability to proliferate, migrate, and invade as compared to the control cells, which is similar to the effects induced by the CXCR4 inhibitor, AMD3100. Consistent with in vitro results, we also confirmed that exendin-4 indirectly targeted pancreatic cancer cells in vivo by attenuating the function of PSCs and suppressing the deposition of extracellular matrix.

Conclusion

These results revealed that exendin-4-treated PSCs could suppress pancreatic cancer cell proliferation and invasion, offering a potential strategy for the treatment of pancreatic cancer.

Circ_0004913 sponges miR-1290 and regulates FOXC1 to inhibit the proliferation of hepatocellular carcinoma

Background

Circular RNA (circRNA), an novel type of non-coding RNA, could interact with miRNA and protein molecules to regulate the occurrence and progression of hepatocellular carcinoma (HCC). However, little is known about the pathogenesis of circ_0004913 in HCC.

Materials

Through the GEO (Gene Expression Omnibus database) to find dysfunctional circRNAs in HCC, and circ_0004913 was selected as the research object. Quantitative reverse transcription PCR (qRT-PCR) was used to detect the expression level of circ_0067934 in HCC tissues and cells. CCK-8, Edu and flow cytometry assays were used to determine the malignant behavior of transfected HCC cells. Mechanistically, RNA immunoprecipitation and dual-luciferase reporter gene assay were performed to explore the relation between circ_0067934, miR-1290 and FOXC1 (Forkhead box C1) in HCC.

Results

The expression of circ_0004913 was down-regulated in HCC tissues and cell lines, while the overexpression of circ_0004913 attenuates the malignant behavior of HCC cells. Bioinformatics predicted that circ_0004913 interacts with miR-1290, which targeted FOXC1 mRNA. In fact, miR-1290 promoted the malignant behavior of HCC cells, while FOXC1 had the opposite effect. In addition, circ_0004913 overexpression enhanced FOXC1 expression by reducing miR-1290 expression, thereby inhibiting the proliferation of HCC cells.

Conclusions

Circ_0004913 / miR-1290 / FOXC1 regulatory axis could inhibit the progress of HCC. Our findings may provide potential new targets for the diagnosis and treatment of HCC.

Exosomes: key players in cancer and potential therapeutic strategy

Exosomes are extracellular vesicles secreted by most eukaryotic cells and participate in intercellular communication. The components of exosomes, including proteins, DNA, mRNA, microRNA, long noncoding RNA, circular RNA, etc., which play a crucial role in regulating tumor growth, metastasis, and angiogenesis in the process of cancer development, and can be used as a prognostic marker and/or grading basis for tumor patients. Hereby, we mainly summarized as followed: the role of exosome contents in cancer, focusing on proteins and noncoding RNA; the interaction between exosomes and tumor microenvironment; the mechanisms that epithelial-mesenchymal transition, invasion and migration of tumor affected by exosomes; and tumor suppression strategies based on exosomes. Finally, the application potential of exosomes in clinical tumor diagnosis and therapy is prospected, which providing theoretical supports for using exosomes to serve precise tumor treatment in the clinic.

Exosomal MicroRNAs and Organotropism in Breast Cancer Metastasis

Breast cancer is the most frequent malignancy for women in which one in eight women will be diagnosed with the disease in their lifetime. Despite advances made in treating primary breast cancer, there is still no effective treatment for metastatic breast cancer. Consequently, metastatic breast cancer is responsible for 90% of breast cancer-related deaths while only accounting for approximately one third of all breast cancer cases. To help develop effective treatments for metastatic breast cancer, it is important to gain a deeper understanding of the mechanisms by which breast cancer metastasizes, particularly, those underlying organotropism towards brain, bone, and lungs. In this review, we will primarily focus on the roles that circulating exosomal microRNAs (miRNAs) play in organotropism of breast cancer metastasis. Exosomes are extracellular vesicles that play critical roles in intercellular communication. MicroRNAs can be encapsulated in exosomes; cargo-loaded exosomes can be secreted by tumor cells into the tumor microenvironment to facilitate tumor-stroma interactions or released to circulation to prime distant organs for subsequent metastasis. Here, we will summarize our current knowledge on the biogenesis of exosomes and miRNAs, mechanisms of cargo sorting into exosomes, the exosomal miRNAs implicated in breast cancer metastasis, and therapeutic exosomal miRNAs.

Advances in the role of exosomal non-coding RNA in the development, diagnosis, and treatment of gastric cancer (Review)

Exosomes are small vesicles secreted by a variety of cells that contain vrious biological macromolecules, including RNA, non-coding RNA and protein. An increasing number of studies have demonstrated that exosomes and particularly the non-coding RNAs they contain, serve important roles in many cellular processes, including the transmission of information. It is well established that the occurrence and development of gastric cancer, one of the four most common malignant tumors worldwide, involves the transmission of information. Based on the urgent need for the elucidation of the mechanism involved in this process, as well as advances in the diagnosis and treatment of gastric cancer, numerous reports have assessed the association between non-coding RNAs in exosomes and gastric cancer. The purpose of the present review was to summarize recent evidence on certain non-coding RNAs associated with the development, diagnosis and treatment of gastric cancer.

High intratumoral expression of eIF4A1 promotes epithelial-to-mesenchymal transition and predicts unfavorable prognosis in gastric cancer

Gastric cancer is an important health problem, being the fifth most common cancer and the third leading cause of cancer-related death worldwide. Aberrant protein translation contributes to the oncogenesis and development of cancers, and upregulation of translation initiation factor eIF4A1 has been observed in several kinds of malignancies. However, the role of eIF4A1 in gastric cancer progression remains unclear. In this study, we found that the expression of eIF4A1, a component of translation initiation complex, was increased in gastric cancer. High expression of eIF4A1 was positively associated with poor tumor differentiation, late T stage, lymph node metastasis, advanced TNM stage, and poor prognosis in patients with gastric cancer. Overexpression of eIF4A1 promoted the migration and invasion of gastric cancer cells in vitro and enhanced tumor metastasis in nude mice model. Mechanism studies revealed that eIF4A1 induced epithelial-to-mesenchymal transition (EMT) of gastric cancer cells through driving the translation of SNAI1 mRNA. Together, these findings indicate that eIF4A1 promotes EMT and metastasis of gastric cancer and suggest that eIF4A1 is a potential target for the adjuvant therapy for gastric cancer patients.

Hypoxia-Induced Adaptations of miRNomes and Proteomes in Melanoma Cells and Their Secreted Extracellular Vesicles

Reduced levels of intratumoural oxygen are associated with hypoxia-induced pro-oncogenic events such as invasion, metabolic reprogramming, epithelial–mesenchymal transition, metastasis and resistance to therapy, all favouring cancer progression. Small extracellular vesicles (EV) shuttle various cargos (proteins, miRNAs, DNA and others). Tumour-derived EVs can be taken up by neighbouring or distant cells in the tumour microenvironment, thus facilitating intercellular communication. The quantity of extracellular vesicle secretion and their composition can vary with changing microenvironmental conditions and disease states. Here, we investigated in melanoma cells the influence of hypoxia on the content and number of secreted EVs. Whole miRNome and proteome profiling revealed distinct expression patterns in normoxic or hypoxic growth conditions. Apart from the well-known miR-210, we identified miR-1290 as a novel hypoxia-associated microRNA, which was highly abundant in hypoxic EVs. On the other hand, miR-23a-5p and -23b-5p were consistently downregulated in hypoxic conditions, while the protein levels of the miR-23a/b-5p-predicted target IPO11 were concomitantly upregulated. Furthermore, hypoxic melanoma EVs exhibit a signature consisting of six proteins (AKR7A2, DDX39B, EIF3C, FARSA, PRMT5, VARS), which were significantly associated with a poor prognosis for melanoma patients, indicating that proteins and/or miRNAs secreted by cancer cells may be exploited as biomarkers.