Circulating exosome-derived bona fide long non-coding RNAs predicting the occurrence and metastasis of hepatocellular carcinoma

Liquid biopsy in hepatocellular carcinoma: Challenges, advances, and clinical implications

Hepatocellular carcinoma (HCC) is an aggressive primary liver malignancy often diagnosed at an advanced stage, resulting in a poor prognosis. Accurate risk stratification and early detection of HCC are critical unmet needs for improving outcomes. Several blood-based biomarkers and imaging tests are available for early detection, prediction, and monitoring of HCC. However, serum protein biomarkers such as alpha-fetoprotein have shown relatively low sensitivity, leading to inaccurate performance. Imaging studies also face limitations related to suboptimal accuracy, high cost, and limited implementation. Recently, liquid biopsy techniques have gained attention for addressing these unmet needs. Liquid biopsy is non-invasive and provides more objective readouts, requiring less reliance on healthcare professional's skills compared to imaging. Circulating tumor cells, cell-free DNA, and extracellular vesicles are targeted in liquid biopsies as novel biomarkers for HCC. Despite their potential, there are debates regarding the role of these novel biomarkers in the HCC care continuum. This review article aims to discuss the technical challenges, recent technical advancements, advantages and disadvantages of these liquid biopsies, as well as their current clinical application and future directions of liquid biopsy in HCC.

Dynamic role of exosomal long non-coding RNA in liver diseases: pathogenesis and diagnostic aspects

BACKGROUND

Liver disease has emerged as a significant health concern, characterized by high rates of morbidity and mortality. Circulating exosomes have garnered attention as important mediators of intercellular communication, harboring protein and stable mRNAs, microRNAs, and long non-coding RNAs (lncRNA). This review highlights the involvement of exosomal lncRNA in the pathogenesis and diagnosis of various liver diseases. Notably, exosomal lncRNAs exhibit therapeutic potential as targets for conditions including hepatic carcinoma, hepatic fibrosis, and hepatic viral infections.

METHOD

An online screening process was employed to identify studies investigating the association between exosomal lncRNA and various liver diseases.

RESULT

Our study revealed a diverse array of lncRNAs carried by exosomes, including H19, Linc-ROR, VLDLR, MALAT1, DANCR, HEIH, ENSG00000248932.1, ENST00000457302.2, ZSCAN16-AS1, and others, exhibiting varied levels across different liver diseases compared to normal liver tissue. These exosomal-derived lncRNAs are increasingly recognized as pivotal biomarkers for diagnosing and prognosticating liver diseases, supported by emerging evidence. However, the precise mechanisms underlying the involvement of certain exosomal lncRNAs remain incompletely understood. Furthermore, the combined analysis of serum exosomes using ENSG00000258332.1, LINC00635, and serum AFP may serve as novel and valuable biomarker for HCC. Clinically, exosomal ATB expression is upregulated in HCC, while exosomal HEIH and RP11-513I15.6 have shown potential for distinguishing HCC related to HCV infection.

CONCLUSION

The lack of reliable biomarkers for liver diseases, coupled with the high specificity and sensitivity of exosomal lncRNA and its non-invasive detection, promotes exploring their role in pathogenesis and biomarker for diagnosis, prognosis, and response to treatment liver diseases.

Exosomal non-coding RNAs (ncRNAs) as potential biomarkers in tumor early diagnosis

Exosomes, extracellular vesicles carrying a cargo rich in various non-coding RNAs (ncRNAs), have emerged as crucial mediators of intercellular communication. Their stability, abundance, and specificity make exosomal ncRNAs promising candidates for biomarker discovery. The discovery of exosomal ncRNAs has unveiled a novel avenue for the exploration of biomarkers in tumor early diagnosis. This review consolidates current knowledge on the role of exosomal ncRNAs as potential biomarkers in the early detection of various tumors. We provide an overview of recent studies demonstrating the diagnostic potential of exosomal ncRNAs across multiple cancer types, highlighting their sensitivity, specificity, and feasibility for early detection. This review underscores the potential of exosomal ncRNAs as non-invasive biomarkers for early tumor diagnosis, paving the way for improved clinical outcomes through timely intervention and personalized management strategies.

Advances and challenges in the use of liquid biopsy in gynaecological oncology

Ovarian cancer, endometrial cancer, and cervical cancer are the three primary gynaecological cancers that pose a significant threat to women's health on a global scale. Enhancing global cancer survival rates necessitates advancements in illness detection and monitoring, with the goal of improving early diagnosis and prognostication of disease recurrence. Conventional methods for identifying and tracking malignancies rely primarily on imaging techniques and, when possible, protein biomarkers found in blood, many of which lack specificity. The process of collecting tumour samples necessitates intrusive treatments that are not suitable for specific purposes, such as screening, predicting, or evaluating the effectiveness of treatment, monitoring the presence of remaining illness, and promptly detecting relapse. Advancements in treatment are being made by the detection of genetic abnormalities in tumours, both inherited and acquired. Newly designed therapeutic approaches can specifically address some of these abnormalities. Liquid biopsy is an innovative technique for collecting samples that examine specific cancer components that are discharged into the bloodstream, such as circulating tumour DNA (ctDNA), circulating tumour cells (CTCs), cell-free RNA (cfRNA), tumour-educated platelets (TEPs), and exosomes. Mounting data indicates that liquid biopsy has the potential to improve the clinical management of gynaecological cancers through enhanced early diagnosis, prognosis prediction, recurrence detection, and therapy response monitoring. Understanding the distinct genetic composition of tumours can also inform therapy choices and the identification of suitable targeted treatments. The main benefits of liquid biopsy are its non-invasive characteristics and practicality, enabling the collection of several samples and the continuous monitoring of tumour changes over time. This review aims to provide an overview of the data supporting the therapeutic usefulness of each component of liquid biopsy. Additionally, it will assess the benefits and existing constraints associated with the use of liquid biopsy in the management of gynaecological malignancies. In addition, we emphasise future prospects in light of the existing difficulties and investigate areas where further research is necessary to clarify its rising clinical capabilities.

Utilizing nullomers in cell-free RNA for early cancer detection

Early detection of cancer can significantly improve patient outcomes; however, sensitive and highly specific biomarkers for cancer detection are currently missing. Nullomers are the shortest sequences that are absent from the human genome but can emerge due to somatic mutations in cancer. We examine over 10,000 whole exome sequencing matched tumor-normal samples to characterize nullomer emergence across exonic regions of the genome. We also identify nullomer emerging mutational hotspots within tumor genes. Finally, we provide evidence for the identification of nullomers in cell-free RNA from peripheral blood samples, enabling detection of multiple tumor types. We show multiple tumor classification models with an AUC greater than 0.9, including a hepatocellular carcinoma classifier with an AUC greater than 0.99.

Diagnostic performance of PIVKA-II in identifying recurrent hepatocellular carcinoma following curative resection: a retrospective cohort study

Protein induced by vitamin K absence or antagonist II (PIVKA-II) plays a critical role in the diagnosis of hepatocellular carcinoma (HCC), however, studies on its efficacy in diagnosing recurrent HCC were rarely found. A multicenter, retrospective, and observational study was conducted. During the overall follow-up of 5 years, HCC patients who had curative resection were monitored every 3 months in the first year post-surgery and every 6 months thereafter if no recurrence occurred. Tumor markers were collected at the diagnosis of recurrence for those with recurrence and at the last follow-up for those without recurrence. The median serum levels of PIVKA-II and AFP in the recurrence group were significantly higher than those in the non-recurrence group (PIVKA-II: 84.62 vs. 18.76 mAU/ml, p < 0.001; AFP: 4.90 vs. 3.00 ng/ml, p < 0.001) and there is a significant correlation between PIVKA-II and AFP (R = 0.901, p < 0.001). PIVKA-II showed better accuracy than AFP in the diagnosis of overall recurrent HCC (AUC: 0.883 vs. 0.672; p < 0.0001), but also in patients with negative PIVKA-II before curative resection (AUC: 0.878 vs. 0.680, p = 0.001). Clinician should pay more attention to serum PIVKA-II values when following patients after curative HCC resection to detect early recurrence.Clinical trial registration: ChiCTR2300070874.

Extracellular Vesicle-Related Non-Coding RNAs in Hepatocellular Carcinoma: An Overview

Hepatocellular carcinoma (HCC) is the most common primary liver cancer. It is a major public health problem worldwide, and it is often diagnosed at advanced stages, when no effective treatment options are available. Extracellular vesicles (EVs) are nanosized double-layer lipid vesicles containing various biomolecule cargoes, such as lipids, proteins, and nucleic acids. EVs are released from nearly all types of cells and have been shown to play an important role in cell-to-cell communication. In recent years, many studies have investigated the role of EVs in cancer, including HCC. Emerging studies have shown that EVs play primary roles in the development and progression of cancer, modulating tumor growth and metastasis formation. Moreover, it has been observed that non-coding RNAs (ncRNAs) carried by tumor cell-derived EVs promote tumorigenesis, regulating the tumor microenvironment (TME) and playing critical roles in the progression, angiogenesis, metastasis, immune escape, and drug resistance of HCC. EV-related ncRNAs can provide information regarding disease status, thus encompassing a role as biomarkers. In this review, we discuss the main roles of ncRNAs present in HCC-derived EVs, including micro(mi) RNAs, long non-coding (lnc) RNAs, and circular (circ) RNAs, and their potential clinical value as biomarkers and therapeutic targets.

Cancer-derived exosomes as novel biomarkers in metastatic gastrointestinal cancer

Gastrointestinal cancer (GIC) is the most prevalent and highly metastatic malignant tumor and has a significant impact on mortality rates. Nevertheless, the swift advancement of contemporary technology has not seamlessly aligned with the evolution of detection methodologies, resulting in a deficit of innovative and efficient clinical assays for GIC. Given that exosomes are preferentially released by a myriad of cellular entities, predominantly originating from neoplastic cells, this confers exosomes with a composition enriched in cancer-specific constituents. Furthermore, exosomes exhibit ubiquitous presence across diverse biological fluids, endowing them with the inherent advantages of non-invasiveness, real-time monitoring, and tumor specificity. The unparalleled advantages inherent in exosomes render them as an ideal liquid biopsy biomarker for early diagnosis, prognosticating the potential development of GIC metastasis.In this review, we summarized the latest research progress and possible potential targets on cancer-derived exosomes (CDEs) in GIC with an emphasis on the mechanisms of exosome promoting cancer metastasis, highlighting the potential roles of CDEs as the biomarker and treatment in metastatic GIC.

Combinatorial Gene Expression Profiling of Serum HULC, HOTAIR, and UCA1 lncRNAs to Differentiate Hepatocellular Carcinoma from Liver Diseases: A Systematic Review and Meta-Analysis

Hepatocellular carcinoma (HCC) presents a significant global health challenge due to limited early detection methods, primarily relying on conventional approaches like imaging and alpha-fetoprotein (AFP). Although non-coding RNAs (ncRNAs) show promise as potential biomarkers in HCC, their true utility remains uncertain. We conducted a comprehensive review of 76 articles, analyzing 88 circulating lncRNAs in 6426 HCC patients. However, the lack of a standardized workflow protocol has hampered holistic comparisons across the literature. Consequently, we herein confined our meta-analysis to only a subset of these lncRNAs. The combined analysis of serum highly upregulated in liver cancer (HULC) gene expression with homeobox transcript antisense intergenic RNA (HOTAIR) and urothelial carcinoma-associated 1 (UCA1) demonstrated markedly enhanced sensitivity and specificity in diagnostic capability compared to traditional biomarkers or other ncRNAs. These findings could have substantial implications for the early diagnosis and tailored treatment of HCC.

Tumor-derived exosomes promote macrophages M2 polarization through miR-1-3p and regulate the progression of liver cancer

Hepatic carcinoma is one of the most life-threatening malignancies in the world. In the clinic, it is urgent to establish a clear mechanism of hepatic carcinoma development as the basis for intervention and treatment. The purpose of this study was to explore the regulatory effect of tumor-derived exosomes on the progression of hepatocellular carcinoma.qPCR was used to detect the expression of miR-1-3p. CCk-8 and EdU staining were used to detect the proliferation and activity of hepatocellular carcinoma cells under different conditions. Transwell assay was used to detect migration and invasion of hepatocellular carcinoma cells. The morphology and size of exosomes were detected by transmission electron microscope and nanoparticle tracking analysis. Western blot was used to detect the expression of markers of exosomes. Immunofluorescence staining was used to explore the location of exosomes in hepatocellular carcinoma cells.The results showed that the expression of miR-1-3p was significantly reduced in hepatocellular carcinoma cells, and the exosomes transfected with miR-1-3p could enter macrophages and express miR-1-3p in large quantities. Macrophages polarized to M2 type under the action of miR-1-3p. Polarized M2 macrophages further down-regulated the proliferation, migration and invasion of Huh-7 cells.In summary, miR-1-3p can enter macrophages through exosomes and affect their polarization, thus affecting the growth of hepatic carcinoma cells. miR-1-3p may be a potentially effective target for regulating liver cancer progression.

An Exosome-Related Long Non-coding RNA (lncRNA)-Based Signature for Prognosis and Therapeutic Interventions in Lung Adenocarcinoma

Background The poor prognosis of lung adenocarcinoma (LUAD) has been confirmed by a large number of studies, so it is necessary to construct a prognosis model. In addition, exosome is closely related to tumors, but there are few studies on exosome-related long non-coding RNA (lncRNA) (ExolncRNA). Methods In this study, we designed a prognostic model, exosome-related lncRNA-based signature (ExoLncSig), using ExolncRNA expression profiles of LUAD patients from The Cancer Genome Atlas (TCGA). ExolncRNAs were identified through univariate and multivariate and Lasso analyses. Subsequently, based on the ExoLncSig, gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, immune function and immunotherapy analysis, drug screening, and so on were performed. Results AC026355.2, AC108136.1, AL590428.1, and LINC01312 were examined to establish the ExoLncSig. Gene enrichment analysis identified potential prognostic markers and therapeutic targets, including human leukocyte antigen (HLA), parainflammation, chemokine receptor (CCR), antigen-presenting cell (APC) co-inhibition, cancer-associated fibroblast (CAF), and myeloid-derived suppressor cell (MDSC). Moreover, we ascertained that the high-risk subgroup exhibits heightened susceptibility to pharmaceutical agents. Conclusion Our findings indicate that ExoLncSig holds promise as a valuable prognostic marker in LUAD. Furthermore, the immunogenic properties of ExolncRNAs may pave the way for the development of a therapeutic vaccine against LUAD.

Engineered exosomes as drug and RNA co-delivery system: new hope for enhanced therapeutics?

Chemotherapy often faces some obstacles such as low targeting effects and drug resistance, which introduce the low therapeutic efficiency and strong side effects. Recent advances in nanotechnology allows the use of novel nanosystems for targeted drug delivery, although the chemically synthesized nanomaterials always show unexpected low biocompability. The emergence of exosome research has offered a better understanding of disease treatment and created novel opportunities for developing effective drug delivery systems with high biocompability. Moreover, RNA interference has emerged as a promising strategy for disease treatments by selectively knocking down or over-expressing specific genes, which allows new possibilities to directly control cell signaling events or drug resistance. Recently, more and more interests have been paid to develop optimal delivery nanosystems with high efficiency and high biocompability for drug and functional RNA co-delivery to achieve enhanced chemotherapy. In light of the challenges for developing drug and RNA co-delivery system, exosomes have been found to show very attractive prospects. This review aims to explore current technologies and challenges in the use of exosomes as drug and RNA co-delivery system with a focus on the emerging trends and issues associated with their further applications, which may contribute to the accelerated developments of exosome-based theraputics.

Liquid biopsy for early detection of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a highly prevalent and lethal cancer globally. Over 90% of HCC cases arise in the context of liver cirrhosis, and the severity of the underlying liver disease or advanced tumor stage at diagnosis significantly limits treatment options. Early diagnosis is crucial, and all guidelines stress the importance of screening protocols for HCC early detection as a public health objective. As serum biomarkers are not optimal for early diagnosis, liquid biopsy has emerged as a promising tool for diagnosis, prognostication, and patients' stratification for personalized therapy in various solid tumors, including HCC. While circulating tumor cells (CTCs) are better suited for personalized therapy and prognosis, cell-free DNA (cfDNA) and extracellular vesicle-based technologies show potential for early diagnosis, HCC screening, and surveillance protocols. Evaluating the added value of liquid biopsy genetic and epigenetic biomarkers for HCC screening is a key goal in translational research. Somatic mutations commonly found in HCC can be investigated in cfDNA and plasma exosomes as genetic biomarkers. Unique methylation patterns in cfDNA or cfDNA fragmentome features have been suggested as innovative tools for early HCC detection. Likewise, extracellular vesicle cargo biomarkers such as miRNAs and long non-coding RNAs may serve as potential biomarkers for early HCC detection. This review will explore recent findings on the utility of liquid biopsy for early HCC diagnosis. Combining liquid biopsy methods with traditional serological biomarkers could improve the overall diagnostic accuracy for early HCC detection.

Characterization of Circulating Tumor Cells Using Imaging Flow Cytometry in Liver Disease Patients

Background

Hepatocellular carcinoma (HCC) is asymptomatic at an early stage which delays its timely diagnosis and treatment. Circulating tumor cells (CTCs), derived from a primary or secondary tumor, may help in the management of HCC. Here, we evaluate and characterize CTCs in liver disease patients.

Methods

In total, 65 patients, categorized into liver cirrhosis (LC) (n = 30) and HCC (n = 35), were enrolled. Using ImagestreamX MkII imaging flow cytometer, CTCs were detected and characterized using biomarker expression of EpCAM, CK, AFP, CD45, and DRAQ5 in LC and HCC patients.

Results

CTCs were detected in 33/35 (94%) HCC patients and in 28/30 (93%) LC patients. In the HCC group, the number of biomarker-positive CTCs was higher in BCLC stage D when compared with others. EpCAM + CK was the most expressed biomarker on CTCs in LC versus HCC (83.3% vs. 77.14%), followed by AFP (80% vs. 65.71%), EpCAM (30% vs. 28.57%), and CK (16.6% vs. 14.28%). The EpCAM cell area was significantly associated (P value = 0.031) with the CTC-positive status. The combination biomarker expression of CTCs cell area (EpCAM, CK, and AFP) performed well with the area under the curve of 0.92, high sensitivity, and specificity in detecting early-stage and AFP-negative HCC as well as in AFP-negative LC cases.

Conclusion

Enumeration and cell area of CTCs may be used as a biomarker for early detection of HCC and guiding treatment.

Risk stratification and early detection biomarkers for precision HCC screening

Hepatocellular carcinoma (HCC) mortality remains high primarily due to late diagnosis as a consequence of failed early detection. Professional societies recommend semi-annual HCC screening in at-risk patients with chronic liver disease to increase the likelihood of curative treatment receipt and improve survival. However, recent dynamic shift of HCC etiologies from viral to metabolic liver diseases has significantly increased the potential target population for the screening, whereas annual incidence rate has become substantially lower. Thus, with the contemporary HCC etiologies, the traditional screening approach might not be practical and cost-effective. HCC screening consists of (i) definition of rational at-risk population, and subsequent (ii) repeated application of early detection tests to the population at regular intervals. The suboptimal performance of the currently available HCC screening tests highlights an urgent need for new modalities and strategies to improve early HCC detection. In this review, we overview recent developments of clinical, molecular, and imaging-based tools to address the current challenge, and discuss conceptual framework and approaches of their clinical translation and implementation. These encouraging progresses are expected to transform the current "one-size-fits-all" HCC screening into individualized precision approaches to early HCC detection and ultimately improve the poor HCC prognosis in the foreseeable future.

Exosomal Long Noncoding RNAs Serve as Biomarkers for Liver Disease

Exosomes are tiny vesicles secreted by cells, with a diameter of 40-160 nm, which contain proteins, DNA, mRNA, long noncoding RNA, etc. Because of the low sensitivity and specificity of the conventional biomarkers for liver diseases, it is of utmost importance to discover novel, sensitive, specific, and non-invasive biomarkers. Exosomal long noncoding RNAs have been considered as potential diagnostic, prognostic, or predictive biomarkers in a wide range of liver pathologies. In this review, we discuss the recent progress on exosomal long noncoding RNAs that serve as potential diagnostic, prognostic, or predictive markers and molecular targets in patients with hepatocellular carcinoma, cholestatic liver injury, viral hepatitis, and alcohol-related liver diseases.

Advances of multi-omics applications in hepatic precancerous lesions and hepatocellular carcinoma: The role of extracellular vesicles

Due to the lack of distinct early symptoms and specific biomarkers, most patients with hepatocellular carcinoma (HCC) are usually diagnosed at advanced stages, rendering the treatment ineffective and useless. Therefore, recognition of the malady at precancerous lesions and early stages is particularly important for improving patient outcomes. The interest in extracellular vesicles (EVs) has been growing in recent years with the accumulating knowledge of their multiple cargoes and related multipotent roles in the modulation of immune response and tumor progression. By virtue of the rapid advancement of high-throughput techniques, multiple omics, including genomics/transcriptomics, proteomics, and metabolomics/lipidomics, have been widely integrated to analyze the role of EVs. Comprehensive analysis of multi-omics data will provide useful insights for discovery of new biomarkers and identification of therapeutic targets. Here, we review the attainment of multi-omics analysis to the finding of the potential role of EVs in early diagnosis and the immunotherapy in HCC.

Liquid Biopsy in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most deadly neoplasms with a poor prognosis. Due to the significant tumor heterogeneity of HCC, alpha-fetoprotein (AFP) or liver biopsy has not yet met the clinical needs in terms of early diagnosis or determining prognosis. In recent years, liquid biopsy techniques that analyze tumor by-products released into the circulation have shown great potential. Its ability to monitor tumors in real time and respond to their global characteristics is expected to improve the management of HCC patients clinically. This review discusses some of the findings of a liquid biopsy in terms of diagnosis and prognosis of HCC.

Exosomal long non-coding RNAs: novel molecules in gastrointestinal cancers' progression and diagnosis

Gastrointestinal (GI) cancers arise in the GI tract and accessory organs, including the mouth, esophagus, stomach, liver, biliary tract, pancreas, small intestine, large intestine, and rectum. GI cancers are a major cause of cancer-related morbidity and mortality worldwide. Exosomes act as mediators of cell-to-cell communication, with pleiotropic activity in the regulation of homeostasis, and can be markers for diseases. Non-coding RNAs (ncRNAs), such as long non-coding RNAs (lncRNAs), can be transported by exosomes derived from tumor cells or non-tumor cells. They can be taken by recipient cells to alter their function or remodel the tumor microenvironment. Moreover, due to their uniquely low immunogenicity and excellent stability, exosomes can be used as natural carriers for therapeutic ncRNAs in vivo. Exosomal lncRNAs have a crucial role in regulating several cancer processes, including angiogenesis, proliferation, drug resistance, metastasis, and immunomodulation. Exosomal lncRNA levels frequently alter according to the onset and progression of cancer. Exosomal lncRNAs can therefore be employed as biomarkers for the diagnosis and prognosis of cancer. Exosomal lncRNAs can also monitor the patient's response to chemotherapy while also serving as potential targets for cancer treatment. Here, we discuss the role of exosomal lncRNAs in the biology and possible future treatment of GI cancer.

HCC biomarkers - state of the old and outlook to future promising biomarkers and their potential in everyday clinical practice

Hepatocellular carcinoma (HCC) is one of the most common and deadly tumors worldwide. Management of HCC depends on reliable biomarkers for screening, diagnosis, and monitoring of the disease, as well as predicting response towards therapy and safety. To date, imaging has been the established standard technique in the diagnosis and follow-up of HCC. However, imaging techniques have their limitations, especially in the early detection of HCC. Therefore, there is an urgent need for reliable, non/minimal invasive biomarkers. To date, alpha-fetoprotein (AFP) is the only serum biomarker used in clinical practice for the management of HCC. However, AFP is of relatively rather low quality in terms of specificity and sensitivity. Liquid biopsies as a source for biomarkers have become the focus of clinical research. Our review highlights alternative biomarkers derived from liquid biopsies, including circulating tumor cells, proteins, circulating nucleic acids, and exosomes, and their potential for clinical application. Using defined combinations of different biomarkers will open new perspectives for diagnosing, treating, and monitoring HCC.

Extracellular vesicles and particles impact the systemic landscape of cancer

Intercellular cross talk between cancer cells and stromal and immune cells is essential for tumor progression and metastasis. Extracellular vesicles and particles (EVPs) are a heterogeneous class of secreted messengers that carry bioactive molecules and that have been shown to be crucial for this cell-cell communication. Here, we highlight the multifaceted roles of EVPs in cancer. Functionally, transfer of EVP cargo between cells influences tumor cell growth and invasion, alters immune cell composition and function, and contributes to stromal cell activation. These EVP-mediated changes impact local tumor progression, foster cultivation of pre-metastatic niches at distant organ-specific sites, and mediate systemic effects of cancer. Furthermore, we discuss how exploiting the highly selective enrichment of molecules within EVPs has profound implications for advancing diagnostic and prognostic biomarker development and for improving therapy delivery in cancer patients. Altogether, these investigations into the role of EVPs in cancer have led to discoveries that hold great promise for improving cancer patient care and outcome.

Intercellular communication in the tumour microecosystem: Mediators and therapeutic approaches for hepatocellular carcinoma

Hepatocellular carcinoma (HCC), one of the most common tumours worldwide, is one of the main causes of mortality in cancer patients. There are still numerous problems hindering its early diagnosis, which lead to late patients receiving treatment, and these problems need to be solved urgently. The tumour microecosystem is a complex network system comprising seven parts: the hypoxia niche, immune microenvironment, metabolic microenvironment, acidic niche, innervated niche, mechanical microenvironment, and microbial microenvironment. Intercellular communication is divided into direct contact and indirect communication. Direct contact communication includes gap junctions, tunneling nanotubes, and receptor-ligand interactions, whereas indirect communication includes exosomes, apoptotic vesicles, and soluble factors. Mechanical communication and cytoplasmic exchange are further means of intercellular communication. Intercellular communication mediates the crosstalk between the tumour microecosystem and the host as well as that between cells and cell-free components in the tumour microecosystem, causing changes in the tumour hallmarks of the HCC microecosystem such as changes in tumour proliferation, invasion, apoptosis, angiogenesis, metastasis, inflammatory response, gene mutation, immune escape, metabolic reprogramming, and therapeutic resistance. Here, we review the role of the above-mentioned intercellular communication in the HCC microecosystem and discuss the advantages of targeted intercellular communication in the clinical diagnosis and treatment of HCC. Finally, the current problems and prospects are discussed.

Diagnostic value of exosomes in patients with liver cancer: a systematic review

BACKGROUND

Liver cancer is a disease with high morbidity and mortality. More and more studies have shown that exosomes can be used as biomarkers for the diagnosis of liver cancer, but their diagnostic accuracy is still unclear. Therefore, this meta-analysis summarizes various studies on the diagnostic value of exosomes for liver cancer.

METHODS

A comprehensive search was carried out based on the set search terms in PubMed, Web of Science and Wiley until April 1, 2022. All statistical analyses were performed by STATA 17 statistical software and Review Manager 5.4. Quality Assessment for Studies of Diagnostic Accuracy 2 tool was applied to evaluate the quality of included articles. Random effects model was used to calculate various diagnostic indicators.

RESULTS

A total of 47 studies were included in this meta-analysis. The number of participants was 3196. The combined sensitivity, specificity and the area under the curve with 95% confidence intervals (95% CI) were, respectively 0.80 (0.75-0.84), 0.83 (0.79-0.87), 0.89 (0.85-0.91).

CONCLUSIONS

This meta-analysis shows that exosomes have good diagnostic accuracy for liver cancer and can be used as an effective biomarker for the diagnosis of liver cancer.

Exosomal Non-Coding RNAs: New Insights into the Biology of Hepatocellular Carcinoma

Exosomes, extracellular vesicles with a diameter of 40 to 160 nm, are among the smallest extracellular vesicles released by cells. They deliver different cargoes, including proteins, DNAs, and RNAs, and facilitate communication between cells to coordinate a variety of physiological and pathological functions. Hepatocellular carcinoma (HCC) is the sixth common malignant tumor and the fourth leading cause of cancer-related death worldwide. Its molecular mechanism remains largely unknown, and there is a lack of reliable and noninvasive biomarkers for early diagnosis and prognosis prediction. Mounting evidence has shown that exosomes carry a variety of ncRNAs, such as long non-coding RNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs), which play critical roles in the occurrence and progression of HCC. In this review, we summarize the recent findings of exosomal miRNAs, lncRNAs, and circRNAs in HCC from their impact on the development of HCC to their potential applications in the diagnosis and treatment of HCC.

Tumor-associated Exosomes Are Involved in Hepatocellular Carcinoma Tumorigenesis, Diagnosis, and Treatment

Hepatocellular carcinoma (HCC) has become a challenging disease worldwide. There are still limitations in the diagnosis and treatment of HCC, and its high metastatic capacity and high recurrence rate are the main reasons for its poor prognosis. The ability of extracellular vesicles (EVs) to transfer functionally-active substances and their widespread presence in almost all body fluids suggest their unprecedented potential in the study of various cancers. The unique physicochemical properties of EVs determine their potential as antitumor vaccines and drug carriers. In the last decade, the study of EVs in HCC has evolved from a single hot topic to a system with considerable scale. This paper summarizes the role of EVs, especially exosomes, in the occurrence, metastasis and tumor immunity of HCC, reviews their applications in tumor diagnosis, prognosis and treatment, describes the pros and cons of these studies, and looks forward towards the future research directions of EVs in HCC.

Extracellular Vesicles and Hepatocellular Carcinoma: Opportunities and Challenges

The incidence of hepatocellular carcinoma (HCC) is increasing worldwide. Extracellular vesicles (EVs) contain sufficient bioactive substances and are carriers of intercellular information exchange, as well as delivery vehicles for nucleic acids, proteins and drugs. Although EVs show great potential for the treatment of HCC and their role in HCC progression has been extensively studied, there are still many challenges such as time-consuming extraction, difficult storage, easy contamination, and low drug loading rate. We focus on the biogenesis, morphological characteristics, isolation and extraction of EVs and their significance in the progression of HCC, tumor invasion, immune escape and cancer therapy for a review. EVs may be effective biomarkers for molecular diagnosis of HCC and new targets for tumor-targeted therapy.

Bioinformatics Study Revealed Significance of Exosome Transcriptome in Hepatocellular Carcinoma Diagnosis

Background: Hepatocellular carcinoma (HCC) is one of the fifty most common cancers globally, having a high mortality rate being the second most common cause of cancer-related deaths. However, little attention has been paid to the involvement of exosomes and ceRNA in HCC.

Method: The study aimed to explore exosome data from exoRBase database and a free online database to estimate possible binding miRNA from mRNA, lncRNA, and circRNA and discover useful exosome biomarkers for HCC therapy.

Results: The results indicated that a total of 159 mRNAs, 60 lncRNAs, and 13 circRNAs were differentially expressed, with HIST2H3C exhibiting the highest log₂FC change, CTD-2031P19 exhibiting the most relevant lncRNA, and CTD-2031P19 exhibiting the most relevant lncRNA. MARCH8, SH3PXD2A, has-circ-0014088, hsa-miR-186-5p, and hsa-miR-613 were identified as hub biomarkers used by Cytoscape. According to the KEGG pathway analysis results, the differentially expressed proteins were primarily enriched in the MAPK signaling network, central carbon metabolism in cancer, the glucagon signaling pathway, glutamatergic synapse, and spliceosome. Furthermore, immunohistochemical images from the Human Protein Atlas (HPA) online tool were used to directly evaluate the protein expression of SMARCA5, CDC42, and UBC between normal and cancer tissues, and the results showed that these three gene expressions were significantly higher in tumor tissues.

Conclusion: This study discovered atypical signature exosomes for HCC prognostic prediction based on an online database. The signals could mimic exosome microenvironmental disorders providing potential biomarkers for exosome treatment.

Clinical Applications of Liquid Biopsy in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a common malignant tumor with high mortality and poor prognosis in the world. The low rate of early diagnosis, as well as the high risk of postoperative metastasis and recurrence, led to the poor clinical prognosis of HCC patients. Currently, it mainly depends on serum markers, imaging examination, and tissue biopsy to diagnose and determine the recurrence and metastasis of HCC after treatments. Nevertheless, the accuracy and sensitivity of serum markers and imaging for early HCC diagnosis are suboptimal. Tissue biopsy, containing limited tissue samples, is insufficient to reveal comprehensive tumor biology information and is inappropriate to monitor dynamic tumor progression due to its invasiveness. Thus, low invasive diagnostic methods and novel biomarkers with high sensitivity and reliability must be found to improve HCC detection and prediction. As a non-invasive, dynamic, and repeatable detection method, “liquid biopsy”, has attracted much attention to early diagnosis and monitoring of treatment response, which promotes the progress of precision medicine. This review summarizes the clinical applications of liquid biopsy in HCC, including circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), and exosome in early diagnosis, prognostic evaluation, disease monitoring, and guiding personalized treatment.

Exosomes as potential diagnosis and treatment for liver cancer

BACKGROUND

Liver cancer is the fourth most significant cause of cancer-related death. Lack of early diagnosis strategy and a scarcity of efficient therapy constitute the main reasons for its lethality. Exosomes, which contain various bioactive molecules, are characterized by high biocompatibility, low immunogenicity, and high transport efficiency. As a result, exosomes have become a research hotspot and present significant potential for cancer diagnosis biomarkers, biotherapeutics, therapy targets, drug carriers and therapeutic agents.

AIM

To explore the potential of exosomes in the diagnosis and treatment of liver cancer.

METHODS

We conducted a systematic literature search via PubMed and Web of Science. The following keywords were used: "exosomal biomarkers", "exosomal therapy", "exosomal therapy", and "liver cancer" or "HCC". The duplicate data were deleted by EndNote software. Literature search focused on full-texts and references of each article were carefully checked. One author (Xiao-Cui Wei) screened the literature that met the following inclusion criteria: (1) Detection of exosomes or their contents in clinical samples (body fluid or tissue); or (2) Exosomes served as drug carriers or therapeutic factors. Two authors (Xiao-Cui Wei and Li-Juan Liu) independently reviewed all retained literature and analyzed the information.

RESULTS

A total of 1295 studies were identified using the systematic literature search. Of these, 835 duplicate studies were removed. A further 402 irrelevant studies were excluded due to being irrelevant, including other diseases, review articles, the literature containing neither clinical samples nor animal experiments, exosome-independent studies, methods for detecting exosomes, or articles in Chinese. Finally, 58 published papers were retained and analyzed in the study. It showed a list of potential exosomal biomarkers that were upregulated in the blood samples of patients with liver cancer. Those downregulated in exosomes might serve as possible biotherapeutics. Some exosomes derived from cells in vitro were used for cytology or animal experiments to explore the mechanism of these exosome contents in disease. These contents might serve as potential targets for liver cancer. Additionally, we also discussed that exosomes serve as drug carriers or therapeutic factors.

CONCLUSION

Exosomes might serve as potential biomarkers or therapeutic biotargets in liver cancer and have the potential to act as drug carriers and self-treatment factors for liver cancer patients.

Current and Emerging Tools for Hepatocellular Carcinoma Surveillance

Hepatocellular carcinoma (HCC) is a leading cause of cancer‐related mortality worldwide. Early detection of HCC enables patients to avail curative therapies that can improve patient survival. Current international guidelines advocate for the enrollment of patients at high risk for HCC, like those with cirrhosis, in surveillance programs that perform ultrasound every 6 months. In recent years, many studies have further characterized the utility of established screening strategies and have introduced new promising tools for HCC surveillance. In this review, we provide an overview of the most promising new imaging modalities and biomarkers for the detection of HCC. We discuss the role of imaging tools like ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI) in the early detection of HCC, and describe recent innovations which can potentially enhance their applicability, including contrast enhanced ultrasound, low‐dose CT scans, and abbreviated MRI. Next, we outline the data supporting the use of three circulating biomarkers (i.e., alpha‐fetoprotein [AFP], AFP lens culinaris agglutinin‐reactive fraction, and des‐gamma‐carboxy prothrombin) in HCC surveillance, and expand on multiple emerging liquid biopsy biomarkers, including methylated cell‐free DNA (cfDNA), cfDNA mutations, extracellular vesicles, and circulating tumor cells. These promising new imaging modalities and biomarkers have the potential to improve early detection, and thus improve survival, in patients with HCC.

Exosome encapsulated ncRNAs in the development of HCC: potential circulatory biomarkers and clinical therapeutic targets

Hepatocellular carcinoma (HCC) is the sixth most deadly malignant cancer in the world and has the third highest mortality rate among cancer-related deaths worldwide. Its poor prognosis can be attributed to late diagnosis, high risk of recurrence and drug resistance. Therefore, finding a new biomarker to help us in the early diagnosis, and exploring the molecular mechanisms involved in recurrence and drug resistance is a reasonable research direction for clinical treatment of HCC. At present, the exosomes related to HCC have been confirmed to carry ncRNAs, transfer them to target cells, and bind corresponding target molecules. Furthermore, they affect the proliferation and metastasis of hepatocellular carcinoma by promoting angiogenesis, epithelial-mesenchymal transition (EMT), and inhibiting the function of the body's immune system. They play an important role in the recurrence and resistance of HCC. Besides, exosomes are stably expressed in body fluids such as sera, are easy to collect and cause little harm to the human body. They are the best candidates for liquid biopsy. Therefore, exosomal ncRNAs have application prospects as biomarkers and targeted molecules for therapy. This article summarizes the current research involving ncRNAs in HCC-related exosomes.

The Role of Extracellular Vesicles in Disease Progression and Detection of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy and one of the leading causes of cancer-related death worldwide. Despite the improvements in surveillance and treatment, the prognosis of HCC remains poor. Extracellular vesicles (EVs) are a heterogeneous group of phospholipid bilayer-enclosed particles circulating in the bloodstream and mediating intercellular communication. Emerging studies have shown that EVs play a crucial role in regulating the proliferation, immune escape, and metastasis of HCC. In addition, because EVs are present in the circulation at relatively early stages of disease, they are getting attention as an attractive biomarker for HCC detection. Over the past decade, dedicated efforts have been made to isolate EVs more efficiently and make them useful tools in different clinical settings. In this review article, we provide an overview of the EVs isolation methods and highlight the role of EVs as mediators in the pathogenesis and progression of HCC. Lastly, we summarize the potential applications of EVs in early-stage HCC detection.

Novel Insights into the Potential Diagnostic Value of Circulating Exosomal IncRNA-Related Networks in Large Artery Atherosclerotic Stroke

Exosomes show diagnostic and therapeutic promise as carriers of ncRNAs in diseases. LncRNAs in exosomes have been identified as being stable and avoided degradation by nucleolytic enzymes. Although lncRNAs have been confirmed to be important in cancers, no studies for exo-lncRNAs have been reported in LAA stroke. High-throughput sequencing was performed to detect the differential expression profiles of lncRNAs in five paired plasma-derived exosome samples from patients with LAA stroke and controls (matched on vascular risk factors). Exo-lncRNA-associated networks were predicted with a combination of multiple databases. The expression of the selected genes in the networks was confirmed by qRT-PCR in a validation set (LAA vs. controls = 30:30). Furthermore, ROC analysis was used to evaluate the diagnostic performance of the lncRNA-related networks. A total of 1,020 differentially expressed lncRNAs were identified in LAA stroke patients. GO and KEGG pathway analyses indicated that their target genes are involved in atherosclerosis-related pathways, including inflammation, cell adhesion, and cell migration. qRT-PCR confirmed that the expression trend of differential expressed genes was consistent with RNA-seq. Furthermore, the AUCs of the lnc_002015-related network and lnc_001350-related network were 0.959 and 0.97, respectively, in LAA stroke. Our study showed the differential expression of lncRNAs in plasma exosomes and presented related diagnostic networks for LAA stroke for the first time. The results suggested that exosomal lncRNA-related networks could be potential diagnostic tools in LAA stroke.

Biomarkers for hepatocellular carcinoma based on body fluids and feces

Novel non-/minimally-invasive and effective approaches are urgently needed to supplement and improve current strategies for diagnosis and management of hepatocellular carcinoma (HCC). Overwhelming evidence from published studies on HCC has documented that multiple molecular biomarkers detected in body fluids and feces can be utilized in early-diagnosis, predicting responses to specific therapies, evaluating prognosis before or after therapy, as well as serving as novel therapeutic targets. Detection and analysis of proteins, metabolites, circulating nucleic acids, circulating tumor cells, and extracellular vesicles in body fluids (e.g., blood and urine) and gut microbiota (e.g., in feces) have excellent capabilities to improve different aspects of management of HCC. Numerous studies have been devoted in identifying more promising candidate biomarkers and therapeutic targets for diagnosis, treatment, and monitoring responses of HCC to conventional therapies, most of which may improve diagnosis and management of HCC in the future. This review aimed to summarize recent advances in utilizing these biomarkers in HCC and discuss their clinical significance.

Liquid Biopsy in Hepatocellular Carcinoma: Where Are We Now?

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer related death worldwide. Diagnostic, prognostic, and predictive biomarkers are urgently needed in order to improve patient survival. Indeed, the most widely used biomarkers, such as alpha-fetoprotein (AFP), have limited accuracy as both diagnostic and prognostic tests. Liver biopsy provides an insight on the biology of the tumor, but it is an invasive procedure, not routinely used, and not representative of the whole neoplasia due to the demonstrated intra-tumoral heterogeneity. In recent years, liquid biopsy, defined as the molecular analysis of cancer by-products, released by the tumor in the bloodstream, emerged as an appealing source of new biomarkers. Several studies focused on evaluating extracellular vesicles, circulating tumor cells, cell-free DNA and non-coding RNA as novel reliable biomarkers. In this review, we aimed to provide a comprehensive overview on the most relevant available evidence on novel circulating biomarkers for early diagnosis, prognostic stratification, and therapeutic monitoring. Liquid biopsy seems to be a very promising instrument and, in the near future, some of these new non-invasive tools will probably change the clinical management of HCC patients.

Quantitative proteomics characterization of cancer biomarkers and treatment

Cancer accounted for 16% of all death worldwide in 2018. Significant progress has been made in understanding tumor occurrence, progression, diagnosis, treatment, and prognosis at the molecular level. However, genomics changes cannot truly reflect the state of protein activity in the body due to the poor correlation between genes and proteins. Quantitative proteomics, capable of quantifying the relatively different protein abundance in cancer patients, has been increasingly adopted in cancer research. Quantitative proteomics has great application potentials, including cancer diagnosis, personalized therapeutic drug selection, real-time therapeutic effects and toxicity evaluation, prognosis and drug resistance evaluation, and new therapeutic target discovery. In this review, the development, testing samples, and detection methods of quantitative proteomics are introduced. The biomarkers identified by quantitative proteomics for clinical diagnosis, prognosis, and drug resistance are reviewed. The challenges and prospects of quantitative proteomics for personalized medicine are also discussed.

Plasma Exosome-Derived Sentrin SUMO-Specific Protease 1: A Prognostic Biomarker in Patients With Osteosarcoma

BACKGROUND

The exosomes contain many important proteins that can be used for early tumor diagnosis or patient prognosis analysis. In this study, we investigated plasma exosome-derived sentrin SUMO-specific protease 1 (SENP1) levels as a prognostic biomarker in patients with osteosarcoma.

METHODS

The expression of SENP1 protein in osteosarcoma tissues and adjacent tissues was detected by immunohistochemistry (IHC). The exosomes were identified by transmission electron microscopy, nanoparticle tracking analysis, and western blotting. ELISA was used to detect plasma exosome-derived SENP1 levels to assess prognosis in patients with osteosarcoma.

RESULTS

IHC showed that the positive expression rate of SENP1 in osteosarcoma tissues was 88.33%, whereas that in adjacent tissues was 46.67% (P < 0.05). Plasma exosome-derived SENP1 levels were related to tumor size, tumor location, necrosis rate, pulmonary metastasis, and surgical stage. Both disease-free survival (DFS) and overall survival (OS) were worse in patients who had higher plasma exosome-derived SENP1 levels compared with those in patients with lower plasma exosome-derived SENP1 levels (P < 0.001). The area under the receiver operating characteristic curve (AUROC) of plasma exosome-derived SENP1, as 1-year DFS and 3-year DFS prognostic biomarkers, was 0.90 (95% CI: 0.83-0.98) and 0.96 (95% CI: 0.94-0.99), respectively. As to OS, the AUROC of plasma exosome-derived SENP1 for 1-year and 3-year prediction was 0.90 (95% CI: 0.82-0.99) and 0.96 (0.93-0.98), respectively. The plasma exosome-derived SENP1 was better than plasma SENP1 as a prognostic biomarker both in DFS and OS.

CONCLUSIONS

Our findings show that the plasma exosome-derived SENP1 may serve as a novel and independent prognostic predictor in clinical applications.

Circulating Long and Circular Noncoding RNA as Non-Invasive Diagnostic Tools of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common causes of cancer-related death worldwide, partially due to late diagnosis of the disease. Growing evidence in the field of biomarker discovery has shown the promising use of nucleic acid in the early detection of many cancers, including HCC. Here, we review data on how various long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs) could be used as a diagnostic tool for HCC being differentially expressed in HCC compared to non-HCC patients. These non-coding RNAs (ncRNAs) showed high stability in the blood being present as free-circulating molecules or encapsulated into exosomes. This review reports some recent evidence on the use of lncRNAs and circRNAs as possible diagnostic biomarkers for HCC. Further, their pathophysiological mechanism in liver carcinogenesis was also described, elucidating the complex regulatory networks making these ncRNAs of particular relevance for the study of liver malignancy cancer.

The Biological Roles of Exosomal Long Non-Coding RNAs in Cancers

Although it has many treatment strategies, cancer is still one of the most common causes of morbidity and mortality in the world. Exosomes are small extracellular vesicles (EVs) that can be secreted by almost all cells. Exosomes can encapsulate various types of molecules, including lipids, proteins, DNA, messenger RNAs, and non-coding RNAs [microRNAs (miRNAs) and long non-coding RNAs (lncRNAs)]. Exosome release is a way of communication between cells. They act as powerful signaling molecules between cancer cells and the surrounding cells that make up the cancer microenvironment. lncRNAs are a class of non-coding P, with a length of more than 200 bp, which are differentially expressed in many cancers. lncRNAs have been widely regarded as a new medium for cancer behavior. The presence of lncRNAs in circulation can be acellular or encapsulated in exosomal bodies released by cancer cells. Exosomal lncRNAs are functional and can transmit different phenotypic patterns to neighboring cells. Here, we reviewed the molecular mechanism of exosomal lncRNAs in regulating cancer progression, angiogenesis, and chemotherapy resistance, as well as the prospective applications of exosomal lncRNAs in cancer diagnosis, treatment and prognosis. These findings potentially promote the current understanding of exosomal lncRNAs and provide a new research direction for exosomal lncRNAs in cancer prevention, diagnosis, and treatment.

Extracellular vesicles as biomarkers in liver diseases: A clinician's point of view

Extracellular vesicles are membrane-bound vesicles containing proteins, lipids, RNAs and microRNAs. They can originate from both healthy and stressed cells, and provide a snapshot of the cell of origin in physiological and pathological circumstances. Various processes that may give rise to the release of extracellular vesicles occur in liver diseases, including hepatocyte apoptosis, hepatic stellate cell activation, liver innate immune system activation, systemic inflammation, and organelle dysfunction (mitochondrial dysfunction and endoplasmic reticulum stress). Numerous studies have therefore investigated the potential role of extracellular vesicles as biomarkers in liver diseases. This review provides an overview of the methods that can be used to measure extracellular vesicle concentrations in clinical settings, ranging from plasma preparation to extracellular vesicle measurement techniques, as well as looking at the challenges of using extracellular vesicles as biomarkers. We also provide a comprehensive review of studies that test extracellular vesicles as diagnostic, severity and prognostic biomarkers in various liver diseases, including non-alcoholic and alcoholic steatohepatitis, viral hepatitis B and C infections, cirrhosis, primary liver cancers, primary sclerosing cholangitis and acute liver failure. In particular, extracellular vesicles could be useful tools to evaluate activity and fibrosis in non-alcoholic fatty liver disease, predict risk of hepatitis B virus reactivation, predict complications and mortality in cirrhosis, detect early hepatocellular carcinoma, detect malignant transformation in primary sclerosing cholangitis and predict outcomes in acute liver failure. While most studies draw on data derived from pilot studies, which still require clinical validation, some extracellular vesicle subpopulations have already been evaluated in solid prospective studies.

Utility of Liquid Biopsy Analysis in Detection of Hepatocellular Carcinoma, Determination of Prognosis, and Disease Monitoring: A Systematic Review

BACKGROUND & AIMS

Liquid biopsies, or blood samples, can be analyzed to detect circulating tumor cells (CTCs), cell-free DNA (cfDNA), and extracellular vesicles, which might identify patients with hepatocellular carcinoma (HCC) or help determine their prognoses. We performed a systematic review of studies of analyses of liquid biopsies from patients with HCC and their comparisons with other biomarkers.

METHODS

We performed a systematic review of original studies published before December 1, 2019. We included studies that compared liquid biopsies alone and in combination with other biomarkers for the detection of HCC, performed multivariate analyses of the accuracy of liquid biopsy analysis in determining patient prognoses, or evaluated the utility of liquid biopsy analysis in monitoring treatment response.

RESULTS

Our final analysis included 112 studies: 67 on detection, 46 on determining prognosis, and 25 on treatment monitoring or selection. Ten studies evaluated assays that characterized cfDNA for detection of HCC in combination with measurement of α-fetoprotein (AFP)-these studies found that the combined measurement of cfDNA and AFP more accurately identified patients with HCC than measurement of AFP alone. Six studies evaluated assays for extracellular vesicles and 2 studies evaluated assays for CTC in detection of HCC, with and without other biomarkers-most of these studies found that detection of CTCs or extracellular vesicles with AFP more accurately identified patients with HCC than measurement of AFP alone. Detection of CTCs before surgery was associated with HCC recurrence after resection in 13 of 14 studies; cfDNA and extracellular vesicles have been studied less frequently as prognostic factors. Changes in CTC numbers before vs after treatment more accurately identify patients with HCC recurrence than pretreatment counts alone, and measurements of cfDNA can identify patients with disease recurrence or progression before changes can be detected by imaging. We found little evidence that analyses of liquid biopsies can aid in the selection of treatment for HCC. Quality assessment showed risk of bias in studies of HCC detection and determination of prognosis.

CONCLUSIONS

In a systematic review of 112 studies of the accuracy of liquid biopsy analysis, we found that assays for CTCs and cfDNA might aid in determining patient prognoses and monitoring HCC, and assays for cfDNA might aid in HCC detection, but there is a risk of bias in these studies. Studies must be standardized before we can assess the clinical utility of liquid biopsy analysis in the detection and management of patients with HCC.

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.

Exosome-Delivered LncHEIH Promotes Gastric Cancer Progression by Upregulating EZH2 and Stimulating Methylation of the GSDME Promoter

Gastric cancer is the third leading cause of cancer-related deaths worldwide and is characterized by poor survival and high recurrence rates. Long non-coding RNAs (lncRNAs) have gained considerable attention in recent years as prognostic markers and gene regulators in various cancers. Here, we found that lncHEIH was upregulated in gastric cancer tissues and cell lines and positively correlated with high expression levels of EZH2. Mechanistically, the lncHEIH-EZH2 axis could promote the progression of gastric cancer. In addition, lncHEIH encapsulated in exosomes was released by gastric cancer cells and then absorbed by normal gastric cells. The uptake of lncHEIH resulted in the upregulation of EZH2, which inhibited the expression of the tumor suppressor GSDME by methylation of the GSDME promoter, promoting the malignant transformation of normal gastric cells. Overall, lncHEIH promotes gastric cancer progression by upregulating the expression of EZH2 and reducing the expression of GSDME in normal cells to induce malignant cell proliferation and migration, indicating its potential as a target in gastric cancer therapy.

Diagnostic performance of blood-based liquid biopsies in hepatocellular carcinoma: A protocol for systematic review and meta-analysis

BACKGROUND

Hepatocellular carcinoma (HCC) is an aggressive cancer associated with poor prognosis. Early diagnosis is crucial to improve its prognosis. Blood-based liquid biopsies are promising methods in detecting HCC. However, their accuracies have not been systematically assessed, so it is essential to conduct a meta-analysis to evaluate the diagnostic performance of blood-based liquid biopsies in detecting HCC.

METHODS

We will search PubMed, EMBASE, Cochrane Library, Web of Science, Medline, China National Knowledge Infrastructure(CNKI) for the relevant studies that assessed the diagnostic performance of blood-based liquid biopsies including circulating tumor cells(CTCs), circulating tumor DNA(ctDNA), and exosomes(EVs) in HCC patients from inception to September 2020. Two researchers will independently extract the data and use Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) to evaluate the quality of included literature. We will also conduct the pool diagnostic value, heterogeneity across studies and reporting bias. All the statistical analysis will be conducted by Stata V.15.0 and Meta-disc V.1.4.

RESULTS

This review will evaluate the pooled diagnostic value of blood-based liquid biopsies in HCC.

CONCLUSION

This review will summarize the current published evidence of blood-based liquid biopsies in diagnosing HCC, which may provide a great opportunity for promotion and application of them.

OPEN SCIENCE FRAMEWORK(OSF) REGISTRATION NUMBER

September 3, 2020. https://osf.io/9n4yz.

Exosome: a significant nano-scale drug delivery carrier

In recent years, due to the limitations of the nature of therapeutic agents, many synthetic nano-delivery systems have emerged to enhance the efficacy of drugs. Extracellular vesicles are currently a class of natural nano-scale drug carriers released by cells. As a tiny vesicle with a lipid bilayer membrane that can be secreted by most cells in the body, exosomes carry and transmit important signal molecules, Therefore, they have been a research hotspot in biomedicine and biomaterials due to their size advantages and huge potential in drug therapy. Many people are optimistic about the clinical application prospects of exosomes and are actively exploring the broad functions of exosomes and developing exosome therapeutic agents to make positive contributions to human health. In this review, we provide basic knowledge and focus on summarizing the advantages of exosomes as drug carriers, methods of loading drugs, targeting strategies, in vivo and in vitro tracing methods, and some of the latest developments in exosomes as drug carriers. In particular, the review provides an outlook for this field.

A panel of circulating long non-coding RNAs as liquid biopsy biomarkers for breast and cervical cancers

The early detection and diagnosis of cancer is critical to optimize the treatment and management of cancer patients. Typical methods such as imaging and tissue biopsy are invasive, time-consuming, and often imprecise. Thus, recent technological advances of dependable, facile, and minimally invasive collectible oncogenic biomarkers using human biofluids and secretions have been an active area of research. Recently, circulating long non-coding RNAs (lncRNAs) have been identified as promising biomarkers that fulfill many recommended properties of successful biomarkers for cancer diagnosis and prognosis. LncRNAs play essential roles in many cellular processes including DNA repair, cell proliferation, and epithelial-to-mesenchymal transition (EMT) by regulating the expression of various genes associated with cancer development and progression. Herein, we discuss the regulatory functions/pathways associated with multiple cancer-associated lncRNAs and their potential as prognostic/diagnostic markers for breast and cervical cancers. Additionally, we provide a correlation between lncRNA levels in the blood and clinicopathological data, including sensitivity, specificity, and Area Under Curve (AUC) merits of model performance value.

Circulating exosome-derived bona fide long non-coding RNAs predicting the occurrence and metastasis of hepatocellular carcinoma

Although the diagnosis and therapy approach developed, techniques for the early diagnosis of HCC remain insufficient which results in poor prognosis of patients. The traditional biomarker AFP, however, has been proved with low specificity. Circulating exosomal ncRNAs revealed different profiles reflecting the characteristics of tumour. In this study, we mainly focused on circulating exosomal ncRNAs which might be the fingerprint for HCC, especially for the diagnosis or metastasis prediction. A high throughput lncRNA microarray in exosomes extracted from cell‐free plasma was applied. The risk score analysis was employed to screen the potential exosome‐derived lncRNAs in two independent sets based on different clinical parameters in 200 paired HCC patients. After a multi‐stage validation, we finally revealed three lncRNAs, ENSG00000248932.1, ENST00000440688.1 and ENST00000457302.2, increased in HCC comparing with the both chronic hepatitis (CH) patients and cancer‐free controls. ROC curve revealed a higher sensitivity and specificity in predicting the occurrence of HCC from cancer‐free controls and CH patients with the area under curve (AUC) of 0.905 and 0.879 by combining AFP. The three lncRNA panel combined with AFP also indicted a fingerprint function in predicting the metastasis of HCC with the AUC of 0.870. In conclusion, ENSG00000248932.1, ENST00000440688.1 and ENST00000457302.2 might be the potential biomarker for the tumorigenesis prediction from CH patients or healthy controls and may also be applied for dynamic monitoring the metastasis of HCC.