EIF3C-enhanced exosome secretion promotes angiogenesis and tumorigenesis of human hepatocellular carcinoma

Tumor cells-derived extracellular vesicles carry circ_0064516 competitively inhibit microRNA-6805-3p and promote cervical cancer angiogenesis and tumor growth

BACKGROUND

The current study tried to elucidate the regulatory role of tumor cell-derived exosomes (Exos)-circ_0064516 in angiogenesis and growth of cervical cancer.

RESEARCH DESIGN AND METHODS

Related cirRNAs and downstream target genes were identified through bioinformatics analysis. Exos were isolated from cervical cancer cell line CaSki, followed by co-cultured with human umbilical vein endothelial cells (HUVECs). Then, the roles of circ_0064516, miR-6805-3p, and MAPK1 in migration and angiogenesis of HUVECs were assayed. Furthermore, xenografted tumors were transplanted into nude mice for in vivo validation.

RESULTS

In vitro assay validated highly expressed circ_0064516 in cervical cancer cells. Tumor cell-derived Exos carried circ_0064516 to HUVECs. circ_0064516 increased MAPK1 expression by binding to miR-6805-3p, thus enhancing migration and angiogenesis. Exos containing circ_0064516 also promoted tumorigenesis of cervical cancer cells in nude mice.

CONCLUSIONS

We confirmed the oncogenic role of tumor cell-derived Exos carrying circ_0064516 in cervical cancer progression through miR-6805-3p/MAPK1.

Cancer metastasis under the magnifying glass of epigenetics and epitranscriptomics

Most of the cancer-associated mortality and morbidity can be attributed to metastasis. The role of epigenetic and epitranscriptomic alterations in cancer origin and progression has been extensively demonstrated during the last years. Both regulations share similar mechanisms driven by DNA or RNA modifiers, namely writers, readers, and erasers; enzymes responsible of respectively introducing, recognizing, or removing the epigenetic or epitranscriptomic modifications. Epigenetic regulation is achieved by DNA methylation, histone modifications, non-coding RNAs, chromatin accessibility, and enhancer reprogramming. In parallel, regulation at RNA level, named epitranscriptomic, is driven by a wide diversity of chemical modifications in mostly all RNA molecules. These two-layer regulatory mechanisms are finely controlled in normal tissue, and dysregulations are associated with every hallmark of human cancer. In this review, we provide an overview of the current state of knowledge regarding epigenetic and epitranscriptomic alterations governing tumor metastasis, and compare pathways regulated at DNA or RNA levels to shed light on a possible epi-crosstalk in cancer metastasis. A deeper understanding on these mechanisms could have important clinical implications for the prevention of advanced malignancies and the management of the disseminated diseases. Additionally, as these epi-alterations can potentially be reversed by small molecules or inhibitors against epi-modifiers, novel therapeutic alternatives could be envisioned.

Complement factor H attenuates TNF-α-induced inflammation by upregulating EIF3C in rheumatoid arthritis

OBJECTIVE

To explore the role and underlying mechanism of Complement Factor H (CFH) in the peripheral and joint inflammation of RA patients.

METHODS

The levels of CFH in the serum and synovial fluid were determined by ELISA. The pyroptosis of monocytes was determined by western blotting and flow cytometry. The inflammation cytokine release was tested by ELISA. The cell migration and invasion ability of fibroblast-like synoviocytes (FLS) were tested by Wound healing Assay and transwell assay, respectively. The potential target of CFH was identified by RNA sequencing.

RESULTS

CFH levels were significantly elevated in the serum and synovial fluid from RA and associated with high sensitivity C-reactive protein (hs-CRP), erythrocyte sedimentation rate (ESR), and disease activity score 28 (DAS28). TNF-α could inhibit CFH expression, and CFH combined with TNF-α significantly decreased cell death, cleaved-caspase 3, gasdermin E N-terminal (GSDME-N), and inflammatory cytokines release (IL-1β and IL-6) of RA-derived monocytes. Stimulated with TNF-α increased CFH levels in RA FLS and CFH inhibits the migration, invasion, and TNF-α-induced production of inflammatory mediators, including proinflammatory cytokines (IL-6, IL-8) as well as matrix metalloproteinases (MMPs, MMP1 and MMP3) of RA FLSs. The RNA-seq results showed that CFH treatment induced upregulation of eukaryotic translation initiation factor 3 (EIF3C) in both RA monocytes and FLS. The migration of RA FLSs was promoted and the expressions of IL-6, IL-8, and MMP-3 were enhanced upon EIF3C knockdown under the stimulation of CFH combined with TNF-α.

CONCLUSION

In conclusion, we have unfolded the anti-inflammatory roles of CFH in the peripheral and joints of RA, which might provide a potential therapeutic target for RA patients.

Mechanism of LEF1-AS1 regulating HUVEC cells by targeting miR-489-3p/S100A11 axis

Background

The venous malformation is the most common congenital vascular malformation and exhibits the characteristics of local invasion and lifelong progressive development. Long noncoding RNA (lncRNA) regulates endothelial cells, vascular smooth muscle cells, macrophages, vascular inflammation, and metabolism and also affects the development of venous malformations. This study aimed to elucidate the role of the lncRNA LEF1-AS1 in the development of venous malformations and examine the interaction among LEF1-AS1, miR-489-3p, and S100A11 in HUVEC cells.

Methods

Venous malformation tissues, corresponding normal venous tissues, and HUVEC cells were used. Agilent human lncRNA microarray gene chip was used to screen differential genes, RNA expression was detected using quantitative reverse transcription PCR, and protein expression was detected using Western blotting. The proliferation, migration, and angiogenesis of HUVEC cells were assessed using CCK8, transwell, and in vitro angiogenesis tests.

Results

A total of 1,651 lncRNAs were screened using gene chip analysis, of which 1015 were upregulated and 636 were downregulated. The lncRNA LEF1-AS1 was upregulated with an obvious difference multiple, and the fold-change value was 11.03273. The results of the analysis performed using the StarBase bioinformatics prediction website showed that LEF1-AS1 and miR-489-3p possessed complementary binding sites and that miR-489-3p and S100A11 also had complementary binding sites. The findings of tissue experiments revealed that the expressions of LEF1-AS1 and S100A11 were higher in tissues with venous malformations than in normal tissues, whereas the expression of miR-489-3p was lower in venous malformations than in normal tissues. Cell culture experiments indicated that LEF1-AS1 promoted the proliferation, migration, and angiogenesis of HUVEC cells. In these cells, LEF1-AS1 targeted miR-489-3p, which in turn targeted S100A11. LEF1-AS1 acted as a competitive endogenous RNA and promoted the expression of S100A11 by competitively binding to miR-489-3p and enhancing the proliferation, migration, and angiogenesis of HUVEC cells. Thus, LEF1-AS1 participated in the occurrence and development of venous malformation.

Conclusions

The expression of LEF1-AS1 was upregulated in venous malformations, and the expression of S100A11 was increased by the adsorption of miR-489-3p to venous endothelial cells, thus enhancing the proliferation, migration, and angiogenesis of HUVEC cells. In conclusion, LEF1-AS1 is involved in the occurrence and development of venous malformations by regulating the miR-489-3p/S100A11 axis, which provides valuable insights into the pathogenesis of this disease and opens new avenues for its treatment.

Expression profiles and function prediction of tRNA-derived fragments in glioma

BACKGROUND

Glioblastoma (GBM) is the most aggressive malignant primary brain tumor. The transfer RNA-derived fragments (tRFs) are a new group of small noncoding RNAs, which are dysregulated in many cancers. Until now, the expression and function of tRFs in glioma remain unknown.

METHODS

The expression profiles of tRF subtypes were analyzed using the Cancer Genome Atlas (TCGA)-low-grade gliomas (LGG)/GBM dataset. The target genes of tRFs were subjected to Gene Ontology, Kyoto Encyclopedia and Gene set enrichment analysis of Genes and Genomes pathway enrichment analysis. The protein-protein interaction enrichment analysis was performed by STRING. QRT-PCR was performed to detect the expressions of tRFs in human glioma cell lines U87, U373, U251, and human astrocyte cell line SVG p12. Western blot assay was used to detect to the expression of S100A11. The interaction between tRF-19-R118LOJX and S100A11 mRNA 3'UTR was detected by dual-luciferase reporter assay. The effects of tRF-19-R118LOJX, tRF-19-6SM83OJX and S100A11 on the glioma cell proliferation, migration and in vitro vasculogenic mimicry formation ability were examined by CCK-8 proliferation assay, EdU assay, HoloMonitor cell migration assay and tube formation assay, respectively.

RESULTS

tRF-19-R118LOJX and tRF-19-6SM83OJX are the most differentially expressed tRFs between LGG and GBM groups. The functional enrichment analysis showed that the target genes of tRF-19-R118LOJX and tRF-19-6SM83OJX are enriched in regulating blood vessel development. The upregulated target genes are linked to adverse survival outcomes in glioma patients. tRF-19-R118LOJX and tRF-19-6SM83OJX were identified to suppress glioma cell proliferation, migration, and in vitro vasculogenic mimicry formation. The mechanism of tRF-19-R118LOJX might be related to its function as an RNA silencer by targeting the S100A11 mRNA 3'UTR.

CONCLUSION

tRFs would become novel diagnostic biomarkers and therapeutic targets of glioma, and the mechanism might be related to its post-transcriptionally regulation of gene expression by targeting mRNA 3'UTR.

Application of exosome engineering modification in targeted delivery of therapeutic drugs

Cancer is the leading cause of premature death in humans. Scientists have developed several therapeutic drugs for cancer treatment. However, drug delivery faces many problems. First, traditional drugs do not target tumors and are prone to causing significant toxic side effects. Second, suitable drug carriers are essential for improving drug delivery to tumors or circulating cancer cells. Exosomes are natural extracellular vesicles with low immunogenicity and prolonged blood circulation in vivo. These characteristics render exosomes ideal drug carriers. This review highlights the properties of exosomes and mechanisms of exosome biogenesis. It also summarizes the engineering modification methods for enhancing exosome yield, targeting, and drug-loading capacity.

Role of Exosomal Non-Coding RNA in the Tumour Microenvironment of Genitourinary System Tumours

In recent years, genitourinary system tumors are common in people of all ages, seriously affecting the quality of life of patients, the pathogenesis and treatment of these diseases are constantly being updated and improved. Exosomes, with a lipid bilayer that enable delivery of their contents into body fluids or other cells. Exosomes can regulate the tumor microenvironment, and play an important role in tumor development. In turn, cellular and non-cellular components of tumor microenvironment also affect the occurrence, progression, invasion and metastasis of tumor. Non-coding RNAs have been shown to be able to be ingested and released by exosomes, and are seen as a potential tool in cancer diagnosis and treatment. Here, we summarize the effect of non-coding RNAs of exosome contents on the tumor microenvironment of genitourinary system tumor, expound the significance of non-coding RNAs of exosome in the occurrence, development, diagnosis and treatment of cancers.

The Role of LINC01564, RAMS11, CBX4 and TOP2A in Hepatocellular Carcinoma

Background: Hepatocellular carcinoma (HCC) is the most common histologic type of primary liver cancers worldwide. Hepatitis C virus (HCV) infection remains a major risk factor for chronic liver disease, cirrhosis, and HCC. To understand the molecular pathogenesis of HCC in chronic HCV infection, many molecular markers are extensively studied, including long noncoding RNAs (lncRNA). Objective: To evaluate the expression levels of lncRNAs (LINC01564, RAMS11), CBX4, and TOP2A in patients with chronic HCV infection and patients with HCC on top of chronic HCV infection and correlate these levels with the clinicopathological features of HCC. Subjects and Methods: One hundred and fifty subjects were enrolled in this study and divided into three groups: group I included 50 patients with HCC on top of chronic hepatitis C (CHC), group II included 50 patients with CHC only, and group III included 50 healthy individuals as a control group. LncRNAs relative expression level was determined by RT-PCR. Results: lncRNA (LINC01564, RAMS11), CBX4, and TOP2A relative expression levels were upregulated in both patient groups compared to controls (p < 0.001*), with the highest levels in the HCC group compared with the CHC group. Additionally, these levels were significantly positively correlated with the clinicopathological features of HCC. Conclusions: The lncRNA (LINC01564, RAMS11), CBX4, and TOP2A relative expression levels were upregulated in CHC patients—in particular, patients with HCC. Thus, these circulatory lncRNAs may be able to serve as promising noninvasive diagnostic markers for HCC associated with viral C hepatitis.

H-TEX-mediated signaling between hepatocellular carcinoma cells and macrophages and exosome-targeted therapy for hepatocellular carcinoma

There is increasing evidence for the key role of the immune microenvironment in the occurrence and development of hepatocellular carcinoma. As an important component of the immune microenvironment, the polarization state and function of macrophages determine the maintenance of the immunosuppressive tumor microenvironment. Hepatocellular carcinoma tumor-derived exosomes, as information carriers, regulate the physiological state of cells in the microenvironment and control cancer progression. In this review, we focus on the role of the exosome content in disease outcomes at different stages in the progression of hepatitis B virus/hepatitis C virus-induced hepatocellular carcinoma. We also explore the mechanism by which macrophages contribute to the formation of hepatocellular carcinoma and summarize the regulation of macrophage functions by the heterogeneity of exosome loading in liver cancer. Finally, with the rise of exosome modification in immunotherapy research on hepatocellular carcinoma, we summarize the application prospects of exosome-based targeted drug delivery.

Extracellular vesicles as central regulators of blood vessel function in cancer

Blood vessels deliver oxygen and nutrients that sustain tumor growth and enable the dissemination of cancer cells to distant sites and the recruitment of intratumoral immune cells. In addition, the structural and functional abnormalities of the tumor vasculature foster the development of an aggressive tumor microenvironment and impair the efficacy of existing cancer therapies. Extracellular vesicles (EVs) have emerged as major players of tumor progression, and a growing body of evidence has demonstrated that EVs derived from cancer cells trigger multiple responses in endothelial cells that alter blood vessel function in tumors. EV-mediated signaling in endothelial cells can occur through the transfer of functional cargos such as miRNAs, lncRNAs, cirRNAs, and proteins. Moreover, membrane-bound proteins in EVs can elicit receptor-mediated signaling in endothelial cells. Together, these mechanisms reprogram endothelial cells and contribute to the sustained exacerbated angiogenic signaling typical of tumors, which, in turn, influences cancer progression. Targeting these angiogenesis-promoting EV-dependent mechanisms may offer additional strategies to normalize tumor vasculature. Here, we discuss the current knowledge pertaining to the contribution of cancer cell-derived EVs in mechanisms regulating blood vessel functions in tumors. Moreover, we discuss the translational opportunities in targeting the dysfunctional tumor vasculature using EVs and highlight the open questions in the field of EV biology that can be addressed using mass spectrometry-based proteomics analysis.

EIF3C Promotes Lung Cancer Tumorigenesis by Regulating the APP/HSPA1A/LMNB1 Axis

Objective

This study was designed to explore the role and mechanism of eukaryotic initiation factor 3C (EIF3C) in the proliferation and apoptosis of lung cancer cells.

Methods

EIF3C expression in clinic lung cancer tissues was detected by immunohistochemistry assay. Cell transfection with lentivirus EIF3C short hairpin RNA (shRNA) was performed with Lipofectamine 2000. Cell proliferation was evaluated by Celigo and MTT assays. Caspase-3/7 activity was assessed using caspase-3/7 assay kit for cell apoptosis detection. The apoptosis rate of lung cancer cells was assessed by flow cytometry. A transplanted tumor nude-mouse model was established to clarify the role of EIF3C in lung cancer. The potential mechanism of EIF3C was explored by mRNA microarray analysis. Among the top 30 up- and downregulated mRNAs selected for RT-qPCR, 5 were chosen for western blot analysis.

Results

EIF3C was abnormally overexpressed in lung cancer cell lines and tissues. Silencing EIF3C suppressed the proliferation and promoted the apoptosis of lung cancer cells. In vivo experiments using transplanted tumor nude-mouse model suggested that EIF3C promoted lung cancer tumorigenesis. Further, mRNA microarray analyses identified 189 upregulated and 83 downregulated differentially expressed mRNA between the KD and negative control groups. After validation by RT-qPCR and western blot, three downstream genes (APP, HSPA1A, and LMNB1) were confirmed.

Conclusion

EIF3C overexpression may facilitate the proliferation and hamper the apoptosis of lung cancer cells by regulating the APP/HSPA1A/LMNB1 axis.

Scalable Production of Extracellular Vesicles and Its Therapeutic Values: A Review

Extracellular vesicles (EVs) are minute vesicles with lipid bilayer membranes. EVs are secreted by cells for intercellular communication. Recently, EVs have received much attention, as they are rich in biological components such as nucleic acids, lipids, and proteins that play essential roles in tissue regeneration and disease modification. In addition, EVs can be developed as vaccines against cancer and infectious diseases, as the vesicle membrane has an abundance of antigenic determinants and virulent factors. EVs for therapeutic applications are typically collected from conditioned media of cultured cells. However, the number of EVs secreted by the cells is limited. Thus, it is critical to devise new strategies for the large-scale production of EVs. Here, we discussed the strategies utilized by researchers for the scalable production of EVs. Techniques such as bioreactors, mechanical stimulation, electrical stimulation, thermal stimulation, magnetic field stimulation, topographic clue, hypoxia, serum deprivation, pH modification, exposure to small molecules, exposure to nanoparticles, increasing the intracellular calcium concentration, and genetic modification have been used to improve the secretion of EVs by cultured cells. In addition, nitrogen cavitation, porous membrane extrusion, and sonication have been utilized to prepare EV-mimetic nanovesicles that share many characteristics with naturally secreted EVs. Apart from inducing EV production, these upscaling interventions have also been reported to modify the EVs’ cargo and thus their functionality and therapeutic potential. In summary, it is imperative to identify a reliable upscaling technique that can produce large quantities of EVs consistently. Ideally, the produced EVs should also possess cargo with improved therapeutic potential.

miRNA Regulatory Networks Associated with Peripheral Vascular Diseases

A growing body of evidence indicates a crucial role of miRNA regulatory function in a variety of mechanisms that contribute to the development of diseases. In our previous work, alterations in miRNA expression levels and targeted genes were shown in peripheral blood mononuclear cells (PBMCs) from patients with lower extremity artery disease (LEAD), abdominal aortic aneurysm (AAA), and chronic venous disease (CVD) in comparison with healthy controls. In this paper, previously obtained miRNA expression profiles were compared between the LEAD, AAA, and CVD groups to find either similarities or differences within the studied diseases. Differentially expressed miRNAs were identified using the DESeq2 method implemented in the R programming software. Pairwise comparisons (LEAD vs. AAA, LEAD vs. CVD, and AAA vs. CVD) were performed and revealed 10, 8, and 17 differentially expressed miRNA transcripts, respectively. The functional analysis of the obtained miRNAs was conducted using the miRNet 2.0 online tool and disclosed associations with inflammation and cellular differentiation, motility, and death. The miRNet 2.0 tool was also used to identify regulatory interactions between dysregulated miRNAs and target genes in patients with LEAD, AAA, and CVD. The presented research provides new information about similarities and differences in the miRNA-dependent regulatory mechanisms involved in the pathogenesis of LEAD, AAA, and CVD.

Pathological Contribution of Extracellular Vesicles and Their MicroRNAs to Progression of Chronic Liver Disease

Simple Summary

Extracellular vesicles (EVs) are membrane-enclosed vesicles secreted from most types of cells. EVs encapsulate many diverse bioactive cargoes, such as proteins and nucleic acid, of parental cells and delivers them to recipient cells. Upon injury, the contents altered by cellular stress are delivered into target cells and affect their physiological properties, spreading the disease microenvironment to exacerbate disease progression. Therefore, EVs are emerging as good resources for studying the pathophysiological mechanisms of diseases because they reflect the characteristics of donor cells and play a central role in intercellular communication. Chronic liver disease affects millions of people worldwide and has a high mortality rate. In chronic liver disease, the production and secretion of EVs are significantly elevated, and increased and altered cargoes are packed into EVs, enhancing inflammation, fibrosis, and angiogenesis. Herein, we review EVs released under specific chronic liver disease and explain how EVs are involved in intercellular communication to aggravate liver disease.

Abstract

Extracellular vesicles (EVs) are membrane-bound endogenous nanoparticles released by the majority of cells into the extracellular space. Because EVs carry various cargo (protein, lipid, and nucleic acids), they transfer bioinformation that reflects the state of donor cells to recipient cells both in healthy and pathologic conditions, such as liver disease. Chronic liver disease (CLD) affects numerous people worldwide and has a high mortality rate. EVs released from damaged hepatic cells are involved in CLD progression by impacting intercellular communication between EV-producing and EV-receiving cells, thereby inducing a disease-favorable microenvironment. In patients with CLD, as well as in the animal models of CLD, the levels of released EVs are elevated. Furthermore, these EVs contain high levels of factors that accelerate disease progression. Therefore, it is important to understand the diverse roles of EVs and their cargoes to treat CLD. Herein, we briefly explain the biogenesis and types of EVs and summarize current findings presenting the role of EVs in the pathogenesis of CLD. As the role of microRNAs (miRNAs) within EVs in liver disease is well documented, the effects of miRNAs detected in EVs on CLD are reviewed. In addition, we discuss the therapeutic potential of EVs to treat CLD.

Characteristics of Extracellular Vesicles and Preclinical Testing Considerations Prior to Clinical Applications

Cell therapy products have significant limitations, such as storage instability, difficulties with transportation, and toxicity issues such as tumorigenicity and immunogenicity. Extracellular vesicles (EVs) secreted from cells show potential for therapeutic agent development. EVs have not been widely examined as investigational drugs, and non-clinical studies for the clinical approval of EV therapeutic agents are challenging. EVs contain various materials, such as DNA, cellular RNA, cytokines, chemokines, and microRNAs, but do not proliferate or divide like cells, thus avoiding safety concerns related to tumorigenicity. However, the constituents of EVs may induce the proliferation of normal cells; therefore, the suitability of vesicles should be verified through non-clinical safety evaluations. In this review, the findings of non-clinical studies on EVs are summarized. We describe non-clinical toxicity studies of EVs, which should be useful for researchers who aim to develop these vesicles into therapeutic agents. A new method for evaluating the immunotoxicity and tumorigenicity of EVs should also be developed.

An emerging role of radiation‑induced exosomes in hepatocellular carcinoma progression and radioresistance (Review)

The incidence rates of hepatocellular carcinoma (HCC) worldwide are increasing, and the role of radiotherapy is currently under discussion. Radioresistance is one of the most important challenges in the therapy of HCC compared with other local advanced, recurrent and metastatic cancers. The mechanisms of radioresistance are complex and remain to be fully understood; however, extracellular vesicles have been investigated in recent studies. Exosomes, which are 40- to 150-nm extracellular vesicles released by cancer cells, contain multiple pathogenic components, including proteins, nucleic acids and lipids, and play critical functions in cancer progression. Emerging data indicate a diagnosis potential for exosomes in HCC, since radiation-derived exosomes promote radioresistance. Radiation-based therapy alters the contents and components of exosomes, suggesting that exosomes and their components may serve as prognostic and predictive biomarkers to monitor radiation response. Therefore, understanding the roles and mechanisms of exosomes in HCC progression and radiation response during HCC therapy may increase our knowledge concerning the roles of exosomes in radioresistance, and may lead to novel approaches for HCC prognosis and treatment. The current review summarizes recent studies on exosome involvement in HCC and the molecular changes in exosome components during HCC progression. It also discusses the functions of exosomes in HCC therapy, and highlights the importance of exosomes in HCC progression and resistance for the development of novel therapies.

Exosomes in Pathogenesis, Diagnosis, and Treatment of Hepatocellular Carcinoma

Exosomes are extracellular vesicles with a diameter of 30-150 nm that are released by most types of cells and have been confirmed to be involved in many physical and pathological processes, especially in cell to cell communication. Compared with other vesicles, exosomes have a unique double-layer saclike structure that allows them to be present stably in various body fluids, including blood, cerebrospinal fluid, urine, saliva, and serous cavity effusion. The cargoes of exosomes reflect the characteristics of host cells. Due to the nature of hepatocellular carcinoma (HCC) cells, heterogeneity in the bioactive substances usually exist in exosomes. In addition, exosomes can efficiently deliver cargoes to the target cells to exert pathological functions, playing important role in tumor occurrence, development, metastasis, immune regulation, and drug resistance. Previous studies have been shown that exosomes have wide applications in diagnosis and treatment of HCC. In this review, we discuss these recent findings and highlight the significant roles of exosomes in HCC, focusing on the effect and underlying mechanisms of exosomes to regulate HCC progression and the potential clinical value of exosomes as biomarkers and therapeutic targets.

Role of eIF3C Overexpression in Predicting Prognosis of Intrahepatic Cholangiocarcinoma

BACKGROUND

Elevated expression of eukaryotic initiation factor 3c (eIF3C) was recently uncovered to promote several types of cancer progression by inducing cell proliferation. Here, we aimed to assess the expression and prognostic value of eIF3C in intrahepatic cholangiocarcinoma (ICC) patients.

METHODS

Expression of eIF3C was analyzed by immunohistochemistry in tissue microarrays (TMAs) containing 138 ICC and paired peritumoral tissues from ICC patients. Then, the roles of eIF3C in ICC cells were investigated by RNA interference, and the relationship between the eIF3C and KI67 expression was explored in ICC cells and tissues. Finally, the relation between the eIF3C level and clinicopathologic features of ICC was probed, and Kaplan-Meier and Cox's analyses were performed to assess the prognostic merit of eIF3C and KI67 in ICC patients.

RESULTS

The expression of eIF3C was elevated in ICC tissues compared to paired peritumoral tissues, which was consistent with the result from the GEPIA database. The downregulation of eIF3C in ICC cells impaired the cellular invasion, metastasis, colony formation, and proliferation. Moreover, we further found a positive relationship between the eIF3C and KI67 expression in ICC cells and tissues. The expression of eIF3C in ICC tissues was positively correlated with lymphatic metastasis (p = 0.049), and the high level of KI67 was frequently found in ICC patients with the large tumor (p = 0.028), high serum AFP (p = 0.019), or lymphatic metastasis (p = 0.039). Notably, patients with the eIF3C or KI67 overexpression had shorter overall survival and higher disease-free survival rates than those with low expression of eIF3C or KI67, and the combination of eIF3C or KI67 expression was an independent parameter for predicting the prognosis and recurrence of ICC patients.

CONCLUSIONS

Elevated eIF3C expression promotes ICC development, and combination of eIF3C and KI67 is a valuable predictor of the survival and recurrence of ICC patient.

RNA m6A methylation regulators in ovarian cancer

N6-methyladenosine (m6A) is the most abundant RNA modification of mammalian mRNAs and plays a vital role in many diseases, especially tumours. In recent years, m6A has become the topic of intense discussion in epigenetics. M6A modification is dynamically regulated by methyltransferases, demethylases and RNA-binding proteins. Ovarian cancer (OC) is a common but highly fatal malignancy in female. Increasing evidence shows that changes in m6A levels and the dysregulation of m6A regulators are associated with the occurrence, development or prognosis of OC. In this review, the latest studies on m6A and its regulators in OC have been summarized, and we focus on the key role of m6A modification in the development and progression of OC. Additionally, we also discuss the potential use of m6A modification and its regulators in the diagnosis and treatment of OC.

Role of N6-Methyladenosine (m6A) Methylation Regulators in Hepatocellular Carcinoma

Liver cancer is the fifth most common malignant tumor in terms of incidence and the third leading cause of cancer-related mortality globally. Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer. Although great progress has been made in surgical techniques, hepatic artery chemoembolization, molecular targeting and immunotherapy, the prognosis of liver cancer patients remains very poor. N6-methyladenosine (m6A) is the most abundant internal RNA modification in eukaryotic cells and regulates various stages of the RNA life cycle. Many studies have reported that the abnormal expression of m6A-related regulators in HCC represent diagnostic and prognostic markers and potential therapeutic targets. In this review, firstly, we introduce the latest research on m6A-related regulators in detail. Next, we summarize the mechanism of each regulator in the pathogenesis and progression of HCC. Finally, we summarize the potential diagnostic, prognostic and therapeutic value of the regulators currently reported in HCC.

Small Extracellular Vesicles in the Development, Diagnosis, and Possible Therapeutic Application of Esophageal Squamous Cell Carcinoma

Esophageal squamous cell carcinoma (ESCC) persists among the most lethal and broad-spreading malignancies in China. The exosome is a kind of extracellular vesicle (EV) from about 30 to 200 nm in diameter, contributing to the transfer of specific functional molecules, such as metabolites, proteins, lipids, and nucleic acids. The paramount role of exosomes in the formation and development of ESCC, which relies on promoting intercellular communication in the tumor microenvironment (TME), is manifested with immense amounts. Tumor-derived exosomes (TDEs) participate in most hallmarks of ESCC, including tumorigenesis, invasion, angiogenesis, immunologic escape, metastasis, radioresistance, and chemoresistance. Published reports have delineated that exosome-encapsulated cargos like miRNAs may have utility in the diagnosis, as prognostic biomarkers, and in the treatment of ESCC. This review summarizes the function of exosomes in the neoplasia, progression, and metastasis of ESCC, which improves our understanding of the etiology and pathogenesis of ESCC, and presents a promising target for early diagnostics in ESCC. However, recent studies of exosomes in the treatment of ESCC are sparse. Thus, we introduce the advances in exosome-based methods and indicate the possible applications for ESCC therapy in the future.

Small Extracellular Vesicles and Metastasis-Blame the Messenger

Simple Summary

Due to their systemic nature, metastatic lesions are a major problem for curative cancer treatment. According to a common model for metastasis, tumor cells disseminate by local invasion, survival in the blood stream and extravasation into suitable tissue environments. At secondary sites, metastatic cells adapt, proliferate and foster vascularization to satisfy nutrient and oxygen demand. In recent years, tumors were shown to extensively communicate with cells in the local microenvironment and future metastatic sites by secreting small extracellular vesicles (sEVs, exosomes). sEVs deliver bioactive cargos, e.g., proteins, and in particular, several nucleic acid classes to reprogram target cells, which in turn facilitate tumor growth, cell motility, angiogenesis, immune evasion and establishment of pre-metastatic niches. sEV-cargos also act as biomarkers for diagnosis and prognosis. This review discusses how tumor cells utilize sEVs with nucleic acid cargos to progress through metastasis, and how sEVs may be employed for prognosis and treatment.

Abstract

Cancer is a complex disease, driven by genetic defects and environmental cues. Systemic dissemination of cancer cells by metastasis is generally associated with poor prognosis and is responsible for more than 90% of cancer deaths. Metastasis is thought to follow a sequence of events, starting with loss of epithelial features, detachment of tumor cells, basement membrane breakdown, migration, intravasation and survival in the circulation. At suitable distant niches, tumor cells reattach, extravasate and establish themselves by proliferating and attracting vascularization to fuel metastatic growth. These processes are facilitated by extensive cross-communication of tumor cells with cells in the primary tumor microenvironment (TME) as well as at distant pre-metastatic niches. A vital part of this communication network are small extracellular vesicles (sEVs, exosomes) with a size of 30–150 nm. Tumor-derived sEVs educate recipient cells with bioactive cargos, such as proteins, and in particular, major nucleic acid classes, to drive tumor growth, cell motility, angiogenesis, immune evasion and formation of pre-metastatic niches. Circulating sEVs are also utilized as biomarker platforms for diagnosis and prognosis. This review discusses how tumor cells facilitate progression through the metastatic cascade by employing sEV-based communication and evaluates their role as biomarkers and vehicles for drug delivery.

Strategies to Enhance Extracellular Vesicle Production

Extracellular vesicles (EVs) are sub-micrometer lipid vesicles secreted from parental cells with their information such as DNA, RNA, and proteins. EVs can deliver their cargo to recipient cells and regulate the signaling pathway of the recipient cells to determine their destiny. Depending on the cargo of EVs, the recipient cells can be changed into abnormal state or be relieved from diseases. Therefore, EVs has been spotlighted as emerging therapeutics in biomedical research. However, slow EV secretion rate is the major limitation for the clinical applications of EVs. EV secretion is highly environmental dependent and can be regulated by various stimulants such as chemicals, oxygen levels, pH, radiation, starvation, and culture methods. To overcome the limitation of low productivity of EVs, EV stimulation methods have been widely studied and applied to massive EV productions. Another strategy is the synthesis of artificial EVs from cells by physical methods such as nitrogen cavitation, extrusion via porous membrane, and sonication. These physical methods disrupt cellular membrane and reassemble the membrane to lipid vesicles containing proteins or drugs. In this review, we will focus on how EV generation can be enhanced and recent advances in large scale EV generation strategies.

The significance of exosomal RNAs in the development, diagnosis, and treatment of pancreatic cancer

Exosomes are single-membrane, secreted organelles with a diameter of 30–200 nm, containing diverse bioactive constituents, including DNAs, RNAs, proteins, and lipids, with prominent molecular heterogeneity. Extensive studies indicate that exosomal RNAs (e.g., microRNAs, long non-coding RNAs, and circular RNAs) can interact with many types of cancers, associated with several hallmark features like tumor growth, metastasis, and resistance to therapy. Pancreatic cancer (PaCa) is among the most lethal cancers worldwide, emerging as the seventh foremost cause of cancer-related death in both sexes. Hence, revealing the specific pathogenesis and improving the clinical diagnosis and treatment process are urgently required. As the study of exosomes has become an active area of research, the functional connections between exosomes and PaCa have been deeply investigated. Among these, exosomal RNAs seem to play a significant role in the development, diagnosis, and treatment of PaCa. Exosomal RNAs delivery ultimately modulates the various features of PaCa, and many scholars have interpreted how exosomal RNAs contribute to the proliferation, angiogenesis, migration, invasion, metastasis, immune escape, and drug resistance in PaCa. Besides, recent studies emphasize that exosomal RNAs may serve as diagnostic and prognostic biomarkers or therapeutic targets for PaCa. In this review, we will introduce these recent insights focusing on the discoveries of the relationship between exosomal RNAs and PaCa, and the potentially diagnostic and therapeutic applications of exosomes in PaCa.

Therapeutic Gene Silencing Using Targeted Lipid Nanoparticles in Metastatic Ovarian Cancer

Ovarian cancer is an aggressive tumor owing to its ability to metastasize from stage II onward. Herein, lipid nanoparticles (LNPs) that encapsulate combination of small interfering RNAs (siRNAs), polo-like kinase-1 (PLK1), and eukaryotic translation-initiation factor 3c (eIF3c), to target different cellular pathways essential for ovarian cancer progression are generated. The LNPs are further modified with hyaluronan (tNPs) to target cluster of differentiation 44 (CD44) expressing cells. Interestingly, hyaluronan-coated LNPs (tNPs) prolong functional activity and reduce growth kinetics of spheroids in in vitro assay as compared to uncoated LNPs (uNPs) due to ≈1500-fold higher expression of CD44. Treatment of 2D and 3D cultured ovarian cancer cells with LNPs encapsulating both siRNAs result in 85% cell death and robust target gene silencing. In advanced orthotopic ovarian cancer model, intraperitoneal administration of LNPs demonstrates CD44 specific tumor targeting of tNPs compared to uNPs and robust gene silencing in tissues involved in ovarian cancer pathophysiology. At very low siRNA dose, enhanced overall survival of 60% for tNPs treated mice is observed compared to 10% and 20% for single siRNA-, eIF3c-tNP, and PLK1-tNP treatment groups, respectively. Overall, LNPs represent promising platform in the treatment of advanced ovarian cancer by improving median- and overall-survival.

A meta-analysis on the relationship of exosomes and the prognosis of lung cancer

BACKGROUND

A lot of research evidence shows that exosomes play an indelible role in the prognosis of lung cancer, but there are many disputes. Therefore, we conduct a meta-analysis to further demonstrate.

METHODS

A literature retrieval was performed through a search of PubMed, Embase, Web of Science, Cochrane, CKNI, Wanfang, and other databases to locate documents from the literature that satisfied the inclusion criteria. There were four outcome indicators: overall survival (OS), disease-free survival (DFS), disease-specific survival (DSS), and progression-free survival (PFS). Subgroup analysis was conducted according to sample size, country, detection method, analysis method, and pathological type. Stata 14.0 software was used to evaluate the prognostic value of exosomes in lung cancer.

RESULTS

A total of 2456 patients with lung cancer from 29 studies in 16 articles were included. The expression level of exosomes was closely associated with the OS and DFS of patients, although no statistical difference was observed between exosomes and DSS or PFS. Eighteen studies with 2,110 patients were evaluated to examine the prognostic value of exosomes in lung cancer by exploring the association between exosomes and OS. The results showed that exosomes were strongly associated with worse OS, and the combined hazard ratio (HR) was 2.01 (95% confidence interval [CI]: 1.70-2.39, P = .000). Six studies investigated the association between exosomes and DFS, and showed a pooled HR of 2.48 (95% CI: 1.75-3.53, P = .000).

CONCLUSION

Our analysis indicated that the expression level of exosomes was closely associated with the OS and DFS of patients with lung cancer, suggesting that exosomes are associated with poor prognosis of lung cancer. Exosomes may be a new biomarker for the prognosis of lung cancer, although a large number of prospective studies are still needed to support this.

Exosomal Non-Coding RNAs: Regulatory and Therapeutic Target of Hepatocellular Carcinoma

Exosomes are small extracellular vesicles secreted by most somatic cells, which can carry a variety of biologically active substances to participate in intercellular communication and regulate the pathophysiological process of recipient cells. Recent studies have confirmed that non-coding RNAs (ncRNAs) carried by tumor cell/non-tumor cell-derived exosomes have the function of regulating the cancerous derivation of target cells and remodeling the tumor microenvironment (TME). In addition, due to the unique low immunogenicity and high stability, exosomes can be used as natural vehicles for the delivery of therapeutic ncRNAs in vivo. This article aims to review the potential regulatory mechanism and the therapeutic value of exosomal ncRNAs in hepatocellular carcinoma (HCC), in order to provide promising targets for early diagnosis and precise therapy of HCC.

Utility of a metabolic-associated nomogram to predict the recurrence-free survival of stage I cervical cancer

Aims: To identify metabolism-associated genes (MAGs) that serve as biomarkers to predict prognosis associated with recurrence-free survival (RFS) for stage I cervical cancer (CC). Patients & methods: By analyzing the Gene Expression Omnibus (GEO) database for 258 cases of stage I CC via univariate Cox analysis, LASSO and multivariate Cox regression analysis, we unveiled 11 MAGs as a signature that was also validated using Kaplan-Meier and receiver operating characteristic analyses. In addition, a metabolism-related nomogram was developed. Results: High accuracy of this signature for prediction was observed (area under the curve at 1, 3 and 5 years was 0.964, 0.929 and 0.852 for the internal dataset and 0.759, 0.719 and 0.757 for the external dataset). The high-risk score group displayed markedly worse RFS than did the low-risk score group. The indicators performed well in our nomogram. Conclusions: We identified a novel signature as a biomarker for predicting prognosis and a nomogram to facilitate the individual management of stage I CC patients.

The Emerging Roles of Exosomes in the Chemoresistance of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a common gastrointestinal malignancy with a leading incidence of cancer-related mortality worldwide. Despite the progress of treatment options, there remains low efficacy for patients with intermediate-advanced HCC, due to tumor metastasis, recurrence and chemoresistance. Increasing evidence suggests that exosomes in the tumor microenvironment (TME), along with other extracellular vesicles (EVs) and cytokines, contribute to the drug chemosensitivity of cancer cells. Exosomes, the intercellular communicators in various biological activities, have shown to play important roles in HCC progression. This review summarizes the underlying associations between exosomes and chemoresistance of HCC cells. The exosomes derived from distinct cell types mediate the drug resistance by regulating drug efflux, epithelial-mesenchymal transition (EMT), cancer stem cell (CSC) properties, autophagic phenotypes, as well as the immune response. In summary, TME-related exosomes can be a potential target to reverse chemoresistance and a candidate biomarker of drug efficacy in HCC patients.

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.

Engineering Extracellular Vesicles for Cancer Therapy

Extracellular vesicles (EVs) are lipid bilayer containing nanovesicles that have a predominant role in intercellular communication and cargo delivery. EVs have recently been used as a means for drug delivery and have been depicted to elicit no or minimal immune response in vivo. The stability, biocompatibility and manipulatable tumour homing capabilities of these biological vessels make them an attractive target for the packaging and delivery of drugs and molecules to treat various diseases including cancer. The following chapter will summarise current EV engineering techniques for the purpose of delivering putative drugs and therapeutic molecules for the treatment of cancer. The relevance of EV source will be discussed, as well as the specific modifications required to manufacture them into suitable vehicles for molecular drug delivery. Furthermore, methods of EV cargo encapsulation will be evaluated with emphasis on intercellular coordination to allow for the effective emptying of therapeutic contents into target cells. While EVs possess properties making them naturally suitable nanocarriers for drugs and molecules, many challenges with clinical translation of EV-based platforms remain. These issues need to be addressed in order to harness the true potential of the EV-based therapeutic avenue.

EVs as Potential New Therapeutic Tool/Target in Gastrointestinal Cancer and HCC

For more than a decade, extracellular vesicles (EVs) have been in focus of science. Once thought to be an efficient way to eliminate undesirable cell content, EVs are now well-accepted as being an important alternative to cytokines and chemokines in cell-to-cell communication route. With their cargos, mainly consisting of functional proteins, lipids and nucleic acids, they can activate signalling cascades and thus change the phenotype of recipient cells at local and systemic levels. Their substantial role as modulators of various physiological and pathological processes is acknowledged. Importantly, more and more evidence arises that EVs play a pivotal role in many stages of carcinogenesis. Via EV-mediated communication, tumour cells can manipulate cells from host immune system or from the tumour microenvironment, and, ultimately, they promote tumour progression and modulate host immunity towards tumour's favour. Additionally, the role of EVs in modulating resistance to pharmacological and radiological therapy of many cancer types has become evident lately. Our understanding of EV biology and their role in cancer promotion and drug resistance has evolved considerably in recent years. In this review, we specifically discuss the current knowledge on the association between EVs and gastrointestinal (GI) and liver cancers, including their potential for diagnosis and treatment.

Role of microenvironmental acidity and tumor exosomes in cancer immunomodulation

Tumor microenvironment (TME) is a complex milieu in which tumor grows, develops and progresses through a complex bi-directional cross-talk with immune-, stromal cells, and the extracellular matrix (ECM). In this context, tumor-derived exosomes (TE) drive the fate of tumor cells through a stimulatory or inhibitory role on immune system. In fact, TE can induce the apoptosis of cells of the immune surveillance, and enhance the proliferation and survival of stromal cells that sustain tumor development. However, depending on the molecular cargo, TE are also able to stimulate anti-tumor immune response. TME is mainly characterized by the acidic pH that contributes to tumor development, through multiple mechanisms. Among these, the impairment of tumor immune surveillance does occur within acidic TME, and is directly mediated by acidic pH or by molecular cargo carried by TE. Little is known about the role of TE in immunomodulation in acidic conditions. The present review summarizes the studies describing the role of microenvironmental acidity and TE in immune system modulation.

The m6A reader YTHDF1 promotes ovarian cancer progression via augmenting EIF3C translation

N⁶-Methyladenosine (m⁶A) is the most abundant RNA modification in mammal mRNAs and increasing evidence suggests the key roles of m⁶A in human tumorigenesis. However, whether m⁶A, especially its ‘reader’ YTHDF1, targets a gene involving in protein translation and thus affects overall protein production in cancer cells is largely unexplored. Here, using multi-omics analysis for ovarian cancer, we identified a novel mechanism involving EIF3C, a subunit of the protein translation initiation factor EIF3, as the direct target of the YTHDF1. YTHDF1 augments the translation of EIF3C in an m⁶A-dependent manner by binding to m⁶A-modified EIF3C mRNA and concomitantly promotes the overall translational output, thereby facilitating tumorigenesis and metastasis of ovarian cancer. YTHDF1 is frequently amplified in ovarian cancer and up-regulation of YTHDF1 is associated with the adverse prognosis of ovarian cancer patients. Furthermore, the protein but not the RNA abundance of EIF3C is increased in ovarian cancer and positively correlates with the protein expression of YTHDF1 in ovarian cancer patients, suggesting modification of EIF3C mRNA is more relevant to its role in cancer. Collectively, we identify the novel YTHDF1-EIF3C axis critical for ovarian cancer progression which can serve as a target to develop therapeutics for cancer treatment.

Circulating MicroRNA-423-3p Improves the Prediction of Coronary Artery Disease in a General Population - Six-Year Follow-up Results From the China-Cardiovascular Disease Study

BACKGROUND

Circulating microRNAs (miRNA) are potential prognostic biomarkers for cardiovascular disease. We aimed to identify serum miRNA as an effective predictor for coronary artery disease (CAD) events in a general population cohort.Methods and Results:Serum miRNAs associated with CAD were determined by small RNA sequencing and quantitative RT-PCR. Further, the predictive ability of identified serum miRNAs was measured in a general population of 2,812 people. As a main outcome measure, CAD events were collected for 6 years and included acute myocardial infarction and subsequent myocardial infarction. Out of the 48 miRNA candidates, 5 miRNAs (miR-10a-5p, miR-126-3p, miR-210-3p, miR-423-3p and miR-92a-3p) showed better reliability and repeatability in serum. Then, the association of serum levels of the 5 miRNAs with CAD was validated. Furthermore, miR-10a-5p and miR-423-3p, which showed better performance, were tested in the large cohort, with a median follow up of 6.0 years. In multivariable Cox regression analysis, only miR-423-3p (P for trend<0.001) was able to precisely predict CAD events. Moreover, the addition of circulating miR-423-3p with the traditional risk factors together markedly improved the various model performance measures, including the area under the operating characteristics curve (0.782 vs. 0.806), Akaike Information Criterion (965.845 vs. 943.113) and net reclassification improvement (19.18%).

CONCLUSIONS

Circulating miR-423-3p can improve the prediction of primary CAD outcomes on the basis of a traditional risk factor model in general population.

Exosomal microRNAs-mediated intercellular communication and exosome-based cancer treatment

Exosomes are extracellular vesicles with a diameter of about 30 to 100 nm, which play a crucial role in intercellular communication. Compared with normal cells, the release rate of tumor-derived exosomes (TDEs) significantly increased, and exosomal contents, especially microRNAs (miRNAs), greatly changed. TDEs contribute to the proliferation, metastasis and resistance of tumor cells, regulate immune response and tumor autophagy, and mediate tumor-stroma communication. In addition, exosomes may be involved in tumor complications. In view of the role of exosomes in intercellular communication, exosomes have been developed as tumor biomarkers, therapeutic targets, and drug delivery systems for tumor diagnosis, prognosis and treatment. Despite the many advantages of exosomes, there are many challenges in exosomal development and application, such as incomprehensive understanding of biological functions, safety and specificity for therapeutic use. This article reviews the biogenesis of TDEs and focuses on the role of exosomal miRNAs in intercellular communication and exosome-based treatment for cancer.

Current Knowledge and Future Perspectives on Mesenchymal Stem Cell-Derived Exosomes as a New Therapeutic Agent

Mesenchymal stem cells (MSCs) are on the cusp of regenerative medicine due to their differentiation capacity, favorable culture conditions, ability to be manipulated in vitro, and strong immunomodulatory activity. Recent studies indicate that the pleiotropic effects of MSCs, especially their immunomodulatory potential, can be largely attributed to paracrine factors. Exosomes, vesicles that are 30-150 nanometers in diameter that function in cell-cell communication, are one of the key paracrine effectors. MSC-derived exosomes are enriched with therapeutic miRNAs, mRNAs, cytokines, lipids, and growth factors. Emerging evidences support the compelling possibility of using MSC-derived exosomes as a new form of therapy for treating several different kinds of disease such as heart, kidney, immune diseases, neural injuries, and neurodegenerative disease. This review provides a summary of current knowledge and discusses engineering of MSC-derived exosomes for their use in translational medicine.

The significance of exosomes in the development and treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most commonmalignancy. Exsome plays a significant role in the elucidation of signal transduction pathways between hepatoma cells, angiogenesis and early diagnosis of HCC. Exosomes are small vesicular structures that mediate interaction between different types of cells, and contain a variety of components (including DNA, RNA, and proteins). Numerous studies have shown that these substances in exosomes are involved in growth, metastasis and angiogenesis in liver cancer, and then inhibited the growth of liver cancer by blocking the signaling pathway of liver cancer cells. In addition, the exosomal substances could also be used as markers for screening early liver cancer. In this review, we summarized to reveal the significance of exosomes in the occurrence, development, diagnosis and treatment of HCC, which in turn might help us to further elucidate the mechanism of exosomes in HCC, and promote the use of exosomes in the clinical diagnosis and treatment of HCC.

Upregulated expression of eIF3C is associated with malignant behavior in renal cell carcinoma

Eukaryotic initiation factor 3c (eIF3C) is involved in the initiation of protein translation. Aberrant eIF3C expression has been reported in different types of human cancer. The present study aimed to assess the role of eIF3C in the malignant behavior of renal cell carcinoma in vitro and in vivo. eIF3C expression was assessed in 16 pairs of renal cell carcinoma (RCC) and matched distant normal tissues, and in RCC cell lines using immunohistochemistry. Subsequently, eIF3C was depleted using lentiviral short hairpin RNA and cell proliferation, cell cycle distribution and apoptosis of these eIF3C‑depleted cells were examined. Additionally, tumor cell xenograft assays in nude mice, Affymetrix microarrays and ingenuity pathway analyses were performed. eIF3C expression was upregulated in RCC tissues and cell lines. Depletion of eIF3C reduced tumor cell proliferation and arrested them at the G1 stage, thus promoting their apoptosis in vitro. Depletion of eIF3C also inhibited the formation and growth of tumor cell xenografts in nude mice. In addition, depletion of eIF3C altered the expression levels of 994 differentially expressed genes in RCC cells (516 genes were upregulated and 478 genes were downregulated). The expression levels of phosphorylated‑AKT, c‑JUN and NFKB inhibitor α were lower in the shorth hairpin RNA eIF3C‑transfected RCC cells compared with in the control group. In conclusion, the present study demonstrated that upregulated eIF3C expression contributed to the development and progression of RCC. Future studies should further evaluate whether eIF3C could be used as a potential strategy for RCC targeting therapy.

Mechanisms associated with biogenesis of exosomes in cancer

Intercellular communication between cellular compartments within the tumor and at distant sites is critical for the development and progression of cancer. Exosomes have emerged as potential regulators of intracellular communication in cancer. Exosomes are nanovesicles released by cells that contain biomolecules and are exchanged between cells. Exchange of exosomes between cells has been implicated in a number of processes critical for tumor progression and consequently altering exosome release is an attractive therapeutic target. Here, we review current understanding as well as gaps in knowledge regarding regulators of exosome release in cancer.

Exosomes and Hepatocellular Carcinoma: From Bench to Bedside

As hepatocellular carcinoma (HCC) usually occurs in the background of cirrhosis, which is an end-stage form of liver diseases, treatment options for advanced HCC are limited, due to poor liver function. The exosome is a nanometer-sized membrane vesicle structure that originates from the endosome. Exosome-mediated transfer of proteins, DNAs and various forms of RNA, such as microRNA (miRNA), long noncoding RNA (lncRNA) and messenger RNA (mRNA), contributes to the development of HCC. Exosomes mediate communication between both HCC and non-HCC cells involved in tumor-associated cells, and several molecules are implicated in exosome biogenesis. Exosomes may be potential diagnostic biomarkers for early-stage HCC. Exosomal proteins, miRNAs and lncRNAs could provide new biomarker information for HCC. Exosomes are also potential targets for the treatment of HCC. Notably, further efforts are required in this field. We reviewed recent literature and demonstrated how useful exosomes are for diagnosing patients with HCC, treating patients with HCC and predicting the prognosis of HCC patients.

Cancer cell-derived exosomes promote cell proliferation and inhibit cell apoptosis of both normal lung fibroblasts and non-small cell lung cancer cell through delivering alpha-smooth muscle actin

This study aimed to investigate the effect of non-small cell lung cancer (NSCLC) cell-derived exosome on cell proliferation and apoptosis in normal lung fibroblast cells and NSCLC cells, and whether it regulates cell functions through delivering alpha-smooth muscle actin (ASMA). NSCLC exosomes were extracted from A549 cells, then cocultured with normal lung fibroblasts (HLF1 cells) and NSCLC cells (A549 cells). Blank ShRNA and ASMA ShRNA plasmids were transferred into HLF1 cells/A549 cells with or without NSCLC exosomes, which were divided into 4 groups accordingly: Negative control (NC) group, SH group, Exosome group and Exosome+SH group. Western blot, immunofluorescence, qPCR, CCK-8 and AV/PI were used to detect protein level, gene expression, cell proliferation and cell apoptosis, respectively. In HLF1 cells, cell proliferation was enhanced while cell apoptosis rate was inhibited in Exosome group compared with NC group; and cell proliferation was attenuated while cell apoptosis rate was raised in Exosome+SH group than Exosome group in rescue experiment; the expressions of apoptotic markers C-caspase3 and Bcl-2 also revealed the same trends. Additionally, in A549 cells, cell proliferation was also increased while cell apoptosis was inhibited in Exosome group compared with NC group; and cell proliferation was reduced while cell apoptosis rate was elevated in Exosome+SH group than Exosome group in rescue experiment. In conclusion, NSCLC derived exosomes promote cell proliferation and inhibit cell apoptosis in both normal lung fibroblasts and NSCLC cells by delivering ASMA.

Knockdown of EIF3C promotes human U-2OS cells apoptosis through increased CASP3/7 and Chk1/2 by upregulating SAPK/JNK

Background

As a component of the EIF3 complex, EIF3C is essential for several steps in protein synthesis initiation. Recently, it has been addressed that EIF3C is overexpressed in several human cancers and plays a pivotal role in cell proliferation and tumorigenesis.

Materials and methods

Immunohistochemistry, quantitative real-time PCR (qPCR), and Western blotting assays were employed to determine the expression of EIF3C in osteosarcoma (OsC) tissues obtained from 60 patients. The levels of EIF3C mRNA and protein were assessed by qPCR and Western blotting, respectively. The effect of EIF3C knockdown on OsC cell proliferation was detected by MTT and colony formation assays, respectively. Cell apoptosis induced by EIF3C silencing was analyzed by flow cytometric analysis. PathScan stress and apoptosis signaling antibody array kit was used to analyze the potential effects of EIF3C knockdown on OsC cells.

Results

The levels of EIF3C were high in OsC tissues and cell lines. In addition, EIF3C knockdown by lentivirus-mediated shRNA targeting EIF3C significantly suppressed cell proliferation and colony formation and induced apoptosis in U-2OS cells. Moreover, EIF3C knockdown led to the upregulated expression of CASP3/7, Chk1/2, and SAPK/JNK, indicating that the downregulated expression of EIF3C might be associated with pro-apoptosis of U-2OS cells.

Conclusion

EIF3C may be a promising target for gene therapy of human OsC. However, the precise mechanisms behind the effect of EIF3C on OsC tumorigenesis require further analysis.

Eukaryotic translation initiation factor 3 subunit C is associated with acquired resistance to erlotinib in non-small cell lung cancer

The acquisition of resistance to EGFR tyrosine kinase inhibitors (EGFR-TKIs) is one of the major problems in the pharmacotherapy against non-small cell lung cancers; however, molecular mechanisms remain to be fully elucidated. Here, using a newly-established erlotinib-resistant cell line, PC9/ER, from PC9 lung cancer cells, we demonstrated that the expression of translation-related molecules, including eukaryotic translation initiation factor 3 subunit C (eIF3c), was upregulated in PC9/ER cells by proteome analyses. Immunoblot analyses confirmed that eIF3c protein increased in PC9/ER cells, compared with PC9 cells. Importantly, the knockdown of eIF3c with its siRNAs enhanced the drug sensitivity in PC9/ER cells. Mechanistically, we found that LC3B-II was upregulated in PC9/ER cells, while downregulated by the knockdown of eIF3c. Consistently, the overexpression of eIF3c increased the number of autophagosomes, proposing the causality between eIF3c expression and autophagy. Moreover, chloroquine, an autophagy inhibitor, restored the sensitivity to erlotinib. Finally, immunohistochemical analyses of biopsy samples showed that the frequency of eIF3c-positive cases was higher in the patients with EGFR-TKI resistance than those prior to EGFR-TKI treatment. Moreover, the eIF3c-positive cases exhibited poor prognosis in EGFR-TKI treatment. Collectively, the upregulation of eIF3c could impair the sensitivity to EGFR-TKI as a novel mechanism of the drug resistance.

Role of tumor-derived exosomes in facilitating pre-metastatic niche formation

Metastasis is the biggest obstacle to improving the treatment outcome and prognosis of tumor patients. A better understanding of tumor metastasis mechanism is of great significance to improve cancer diagnosis and treatment levels. Previous studies on metastasis mechanism mainly focus on the interaction between cancer cells and stroma cells in primary tumors. Currently, some studies reveal that soluble factors derived from primary tumor cells reach target organs via systemic circulation and recruit bone marrow-derived cells (BMDCs). The recruited BMDCs interact with intrinsic cells to remodel the matrix microenvironment, ultimately facilitating the formation of pre-metastatic niche and the implementation of tumor metastasis in the target organ. Among them, cancer cell-secreted exosomes serve as an important bridge mediator to link primary tumor and pre-metastatic niche at distant target organ. This article reviews the latest discoveries on exosomes and their effect on pre-metastatic niche of tumor.

Cell‑to‑cell communication via extracellular vesicles among human pancreatic cancer cells derived from the same patient

Despite existing multimodal therapies, pancreatic cancer exhibits high metastatic capability and poor prognosis. Extracellular vesicles (EVs) are nanoparticles comprising lipid bilayers and various other components, such as protein and nucleic acids, derived from secreted cells. Recent research has demonstrated the involvement of EVs released from cancer cells in the metastasis of cancer cells to distant organs. However, the effects of EVs released from pancreatic cancer cells on other pancreatic cancer cells in a tumor microenvironment remain unclear. The present study aimed to elucidate that EVs released from PK‑45H pancreatic cancer cells are taken up by PK‑45P pancreatic cancer cells derived from the same patient through dynamin‑related endocytosis. Additionally, EVs released from PK‑45H cells augment the phosphorylation of classical mitogen‑activated protein kinase (MAPK) pathways in PK‑45P cells. The uptake of EVs released from PK‑45H cells by PK‑45P cells stimulates cell migration through the classical MAPK‑dependent pathway, suggesting that EVs released from one pancreatic cancer cell are taken up by other surrounding pancreatic cancer cells and could be critical inducers of cancer metastasis in the tumor microenvironment.