Urine exosome gene expression of cancer-testis antigens for prediction of bladder carcinoma

Matrix metalloproteinase‑1 and microRNA‑486‑5p in urinary exosomes can be used to detect early lung cancer: A preliminary report

The present study describes a novel molecular-genetic method suitable for lung cancer (LC) screening in the work-place and at community health centers. Using urinary-isolated exosomes from 35 patients with LC and 40 healthy volunteers, the expression ratio of MMP-1/CD63, and the relative expression levels of both microRNA (miRNA)-21 and miRNA-486-5p were measured. MMP-1/CD63 expression ratio was significantly higher in patients with LC than in the healthy controls {1.342 [95% confidence interval (CI): 0.890-1.974] vs. 0.600 (0.490-0.900); P<0.0001}. The relative expression of miRNA-486-5p in male healthy controls was significantly different from that in female healthy controls, whereas there was no significant difference in miRNA-21. Receiver operating characteristic curve (ROC) analysis of MMP-1/CD63 showed 92.5% sensitivity and 54.3% specificity, whereas miRNA-486-5p showed 85% sensitivity and 70.8% specificity for men, and 70.0% sensitivity and 72.7% specificity for women. The logistic regression model used to evaluate the association of LC with the combination of MMP-1/CD63 and miRNA-486-5p revealed that the area under the ROC curve was 0.954 (95% CI: 0.908-1.000), and the model had 89% sensitivity and 88% specificity after adjusting for age, sex and smoking status. These data suggested that the combined analysis of MMP-1/CD63 and miRNA-486-5p in urinary exosomes may be used to detect patients with early-stage LC in the work-place and at community health centers, although confirmational studies are warranted.

Liquid biopsy in urothelial carcinoma: Detection techniques and clinical applications

The types of urothelial carcinoma (UC) include urothelial bladder cancer and upper tract urothelial carcinoma. Current diagnostic techniques cannot meet the needs of patients. Liquid biopsy is an accurate method of determining the molecular profile of UC and is a cutting-edge and popular technique that is expected to complement existing detection techniques and benefit patients with UC. Circulating tumor cells, cell-free DNA, cell-free RNA, extracellular vesicles, proteins, and metabolites can be found in the blood, urine, or other bodily fluids and are examined during liquid biopsies. This article focuses on the components of liquid biopsies and their clinical applications in UC. Liquid biopsies have tremendous potential in multiple aspects of precision oncology, from early diagnosis and treatment monitoring to predicting prognoses. They may therefore play an important role in the management of UC and precision medicine.

Extracellular Vesicles as Potential Bladder Cancer Biomarkers: Take It or Leave It?

Bladder cancer (BC) is the 10th most frequently diagnosed cancer worldwide. Although urine cytology and cystoscopy are current standards for BC diagnosis, both have limited sensitivity to detect low-grade and small tumors. Moreover, effective prognostic biomarkers are lacking. Extracellular vesicles (EVs) are lipidic particles that contain nucleic acids, proteins, and metabolites, which are released by cells into the extracellular space, being crucial effectors in intercellular communication. These particles have emerged as potential tools carrying biomarkers for either diagnosis or prognosis in liquid biopsies namely urine, plasma, and serum. Herein, we review the potential of liquid biopsies EVs’ cargo as BC diagnosis and prognosis biomarkers. Additionally, we address the emerging advantages and downsides of using EVs within this framework.

Biology of Cancer-Testis Antigens and Their Therapeutic Implications in Cancer

Tumour-specific antigens have been an area of interest in cancer therapy since their discovery in the middle of the 20th century. In the era of immune-based cancer therapeutics, redirecting our immune cells to target these tumour-specific antigens has become even more relevant. Cancer-testis antigens (CTAs) are a class of antigens with an expression specific to the testis and cancer cells. CTAs have also been demonstrated to be expressed in a wide variety of cancers. Due to their frequency and specificity of expression in a multitude of cancers, CTAs have been particularly attractive as cancer-specific therapeutic targets. There is now a rapid expansion of CTAs being identified and many studies have been conducted to correlate CTA expression with cancer and therapy-resistant phenotypes. Furthermore, there is an increasing number of clinical trials involving using some of these CTAs as molecular targets in pharmacological and immune-targeted therapeutics for various cancers. This review will summarise the current knowledge of the biology of known CTAs in tumorigenesis and the regulation of CTA genes. CTAs as molecular targets and the therapeutic implications of these CTA-targeted anticancer strategies will also be discussed.

Small extracellular vesicles as a multicomponent biomarker platform in urinary tract carcinomas

Extracellular vesicles are a large group of nano-sized vesicles released by all cells. The variety of possible cargo (mRNAs, miRNAs, lncRNAs, proteins, and lipids) and the presence of surface proteins, signaling molecules, and receptor ligands make them a rich source of biomarkers for malignancy diagnosis. One of the groups gathering the most interest in cancer diagnostic applications is small extracellular vesicles (sEVs), with ≤200 nm diameter, mainly composed of exosomes. Many studies were conducted recently, evaluating the diagnostic potential of sEVs in urinary tract carcinomas (UTCs), discovering and clinically evaluating various classes of biomarkers. The amount of research concerning different types of UTCs understandably reflects their incidence. sEV cargos getting the most interest are non-coding RNAs (miRNA and lncRNA). However, implementation of other approaches such as metabolomic and proteomic analysis is also evaluated. The results of many studies indicate that sEVs have an essential role in the cancer process and possess many possible diagnostic and prognostic applications for UTC. The relative ease of obtaining biofluids rich in sEVs (urine and blood) confirms that sEVs are essential for UTC detection in the liquid biopsy approach. A noticeable rise in research quality is observed as more researchers are aware of the research standardization necessity, which is essential for considering the clinical application of their findings.

Applications of Exosomes in Diagnosing Muscle Invasive Bladder Cancer

Muscle Invasive Bladder Cancer (MIBC) is a subset of bladder cancer with a significant risk for metastases and death. It accounts for nearly 25% of bladder cancer diagnoses. A diagnostic work-up for MIBC is inclusive of urologic evaluation, radiographic imaging with a CT scan, urinalysis, and cystoscopy. These evaluations, especially cystoscopy, are invasive and carry the risk of secondary health concerns. Non-invasive diagnostics such as urine cytology are an attractive alternative currently being investigated to mitigate the requirement for cystoscopy. A pitfall in urine cytology is the lack of available options with high reliability, specificity, and sensitivity to malignant bladder cells. Exosomes are a novel biomarker source which could resolve some of the concerns with urine cytology, due to the high specificity as the surrogates of tumor cells. This review serves to define muscle invasive bladder cancer, current urine cytology methods, the role of exosomes in MIBC, and exosomes application as a diagnostic tool in MIBC. Urinary exosomes as the specific populations of extracellular vesicles could provide additional biomarkers with specificity and sensitivity to bladder malignancies, which are a consistent source of cellular information to direct clinicians for developing treatment strategies. Given its strong presence and differentiation ability between normal and cancerous cells, exosome-based urine cytology is highly promising in providing a perspective of a patient’s bladder cancer.

Extracellular Vesicles: New Tools for Early Diagnosis of Breast and Genitourinary Cancers

Breast cancers and cancers of the genitourinary tract are the most common malignancies among men and women and are still characterized by high mortality rates. In order to improve the outcomes, early diagnosis is crucial, ideally by applying non-invasive and specific biomarkers. A key role in this field is played by extracellular vesicles (EVs), lipid bilayer-delimited structures shed from the surface of almost all cell types, including cancer cells. Subcellular structures contained in EVs such as nucleic acids, proteins, and lipids can be isolated and exploited as biomarkers, since they directly stem from parental cells. Furthermore, it is becoming even more evident that different body fluids can also serve as sources of EVs for diagnostic purposes. In this review, EV isolation and characterization methods are described. Moreover, the potential contribution of EV cargo for diagnostic discovery purposes is described for each tumor.

Extracellular vesicles in urological malignancies

Extracellular vesicles (EVs) are small lipid bound structures released from cells containing bioactive cargoes. Both the type of cargo and amount loaded varies compared to that of the parent cell. The characterisation of EVs in cancers of the male urogenital tract has identified several cargoes with promising diagnostic and disease monitoring potential. EVs released by cancers of the male urogenital tract promote cell-to-cell communication, migration, cancer progression and manipulate the immune system promoting metastasis by evading the immune response. Their use as diagnostic biomarkers represents a new area of screening and disease detection, potentially reducing the need for invasive biopsies. Many validated EV cargoes have been found to have superior sensitivity and specificity than current diagnostic tools currently in use. The use of EVs to improve disease monitoring and develop novel therapeutics will enable clinicians to individualise patient management in the exciting era of personalised medicine.

The expression of miR-17 and miR-29a in placenta-derived exosomes in LPS-induced abortion mice model: An experimental study

Background

The expression pattern of microRNAs in placenta-derived exosomes plays a crucial role in the regulation of immune responses and inflammation at the fetal–maternal interface.

Objective

Considering the immunomodulatory properties of miR-17 and miR-29a, we determined their expression levels in placenta-derived exosomes in a lipopolysaccharide (LPS)-induced abortion mice model.

Materials and Methods

A total of 14 pregnant BALB/c mice, aged 6–8 wk, were randomly divided into two groups (n = 7/each) on the gestational day 11.5. While the mice in the experimental group were treated with LPS, those in the control group were treated with Phosphate buffered saline; 5 hr after the treatment, the placental cells were isolated and cultured for 48 hr. Then, the cell culture supernatants were collected and used for isolation of exosomes. The isolated exosomes were confirmed by western blot and scanning electron microscopy. The miRNAs were then extracted from exosomes, and cDNA synthesized. The expression levels of miR-17 and miR-29a were evaluated by quantitative real-time PCR analysis.

Results

Our results showed that the expression levels of miR-29a in placenta-derived exosomes obtained from the experimental group increased significantly compared to the control group. Also, the expression levels of miR-17 in the placenta-derived exosomes obtained from the experimental group were found to decrease; however, it did not show significant changes compared with the control group (p > 0.05).

Conclusion

Inflammatory reactions at the fetal–maternal interface can alter miRNAs expression patterns in placenta-derived exosomes, especially miRNAs with immunomodulatory effects such as miR-29a.

Exosomes in bladder cancer: novel biomarkers and targets

Exosomes are nanometer-sized vesicles that contain various types of biologically active components, including proteins, nucleic acids, carbohydrates, and lipids, which vary with the type and physiological state of the cell. In recent years, several studies have showed that exosomes can provide new non-invasive diagnostic and prognostic biomarkers in patients affected by cancers, including bladder cancer (BC), and the lipid bilayer membrane structure makes exosomes as promising delivery vehicles for therapeutic applications. Exosomes have the characteristics of high abundance, high stability, tissue specificity, and wide distribution in body fluids, and are secreted as various types by cells in different states, thereby possessing great potential as biomarkers for BC. Herein, we briefly summarize the functions and roles of exosomes in the occurrence and development of BC and the current progress of research on exosomes in BC, while focusing on potential clinical applications of the diagnosis, treatment, and prognosis of BC.

Extracellular Vesicles as Biomarkers Carriers in Bladder Cancer: Diagnosis, Surveillance, and Treatment

Exosomes are extracellular vesicles, enriched in biomolecular cargo consisting of nucleic acids, proteins, and lipids, which take part in intercellular communication and play a crucial role in both physiologic functions and oncogenesis. Bladder cancer is the most common urinary malignancy and its incidence is steadily rising in developed countries. Despite the high five-year survival in patients diagnosed at early disease stage, survival substantially drops in patients with muscle-invasive or metastatic disease. Therefore, early detection of primary disease as well as recurrence is of paramount importance. The role that exosomal biomarkers could play in bladder cancer patient diagnosis and surveillance, as well as their potential therapeutic applications, has not been extensively studied in this malignancy. In the present review, we summarize all relevant data obtained so far from cell lines, animal models, and patient biofluids and tissues. Current literature suggests that urine is a rich source of extracellular vesicle-derived biomarkers, compared with blood and bladder tissue samples, with potential applications in bladder cancer management. Further studies improving sample collection procedures and optimizing purification and analytical methods should augment bladder cancer diagnostic, prognostic, and therapeutic input of extracellular vesicles biomarkers in the future.

Exosome: A New Player in Translational Nanomedicine

Summary: Exosomes are extracellular vesicles released by the vast majority of cell types both in vivo and ex vivo, upon the fusion of multivesicular bodies (MVBs) with the cellular plasma membrane. Two main functions have been attributed to exosomes: their capacity to transport proteins, lipids and nucleic acids between cells and organs, as well as their potential to act as natural intercellular communicators in normal biological processes and in pathologies. From a clinical perspective, the majority of applications use exosomes as biomarkers of disease. A new approach uses exosomes as biologically active carriers to provide a platform for the enhanced delivery of cargo in vivo. One of the major limitations in developing exosome-based therapies is the difficulty of producing sufficient amounts of safe and efficient exosomes. The identification of potential proteins involved in exosome biogenesis is expected to directly cause a deliberate increase in exosome production. In this review, we summarize the current state of knowledge regarding exosomes, with particular emphasis on their structural features, biosynthesis pathways, production techniques and potential clinical applications.

Urinary Biomarkers in Bladder Cancer: Where Do We Stand and Potential Role of Extracellular Vesicles

Extracellular vesicles (EVs) are small membrane vesicles released by all cells and involved in intercellular communication. Importantly, EVs cargo includes nucleic acids, lipids, and proteins constantly transferred between different cell types, contributing to autocrine and paracrine signaling. In recent years, they have been shown to play vital roles, not only in normal biological functions, but also in pathological conditions, such as cancer. In the multistep process of cancer progression, EVs act at different levels, from stimulation of neoplastic transformation, proliferation, promotion of angiogenesis, migration, invasion, and formation of metastatic niches in distant organs, to immune escape and therapy resistance. Moreover, as products of their parental cells, reflecting their genetic signatures and phenotypes, EVs hold great promise as diagnostic and prognostic biomarkers. Importantly, their potential to overcome the current limitations or the present diagnostic procedures has created interest in bladder cancer (BCa). Indeed, cystoscopy is an invasive and costly technique, whereas cytology has poor sensitivity for early staged and low-grade disease. Several urine-based biomarkers for BCa were found to overcome these limitations. Here, we review their potential advantages and downfalls. In addition, recent literature on the potential of EVs to improve BCa management was reviewed and discussed.

Crosstalk between Stress Granules, Exosomes, Tumour Antigens, and Immune Cells: Significance for Cancer Immunity

RNA granules and exosomes produced by tumour cells under various stresses in the microenvironment act as critical determinants of cell survival by promoting angiogenesis, cancer metastasis, chemoresistance, and immunosuppression. Meanwhile, developmental cancer/testis (CT) antigens that are normally sequestered in male germ cells of the testes, but which are overexpressed in malignant tumour cells, can function as tumour antigens triggering immune responses. As CT antigens are potential vaccine candidates for use in cancer immunotherapy, they could be targeted together with crosstalk between stress granules, exosomes, and immune cells for a synergistic effect. In this review, we describe the effects of exosomes and exosomal components presented to the recipient cells under different types of stresses on immune cells and cancer progression. Furthermore, we discuss their significance for cancer immunity, as well as the outlook for their future application.

Top 100 most-cited articles on exosomes in the field of cancer: a bibliometric analysis and evidence mapping

Several studies have demonstrated that exosomes have a very broad prospect in the field of cancer therapy. This study aims to identify the general characteristics, cooperation of authors, countries and explore the hot topics of the top 100 cited articles on tumor-related exosomes. We searched the Web of Science Core Collection on June 28, 2019, to collect related publications. Microsoft Excel 2016 and VOSviewer 1.6.9 were applied to analyze the publication year, citations, authors, countries, institutions, journals, and keywords. The top 100 articles were published between 1998 and 2017 with citations ranging from 181 to 2275. Cancer Research (n = 9) had the highest number of publications. Nature Cell Biology, Nature, and Nature Medicine are considered to be the core journals of tumor-related exosomes because they are among top 10 from different analytical perspectives. The USA (n = 49) and Harvard University (n = 9) were the most productive country and institution, respectively. There were active collaborations between countries. Kalluri R (n = 6) contributed the largest number of articles, and Taylor DD was the most co-cited author. Théry C and Al-Nedawi K are probably the two important experts as they are both the top 10 authors and top 10 co-cited authors. Three clusters were obtained after clustering analysis of the keywords. The main hot topics were the proteomic analysis and mechanism of vesicle activation and the role of exosomes in the diagnosis and progression of tumors. Further research should expand and develop new topics such as the role of exosomes in the treatment of cancers.

Genetic and molecular biology of bladder cancer among Iranian patients

Background

Bladder cancer (BC) is the sixth common cancer among Iranians. Various risk factors such as smoking, body mass index, chronic infection, age, and genetic factors are associated with BC progression.

Methods

It has been shown that a significant ratio of patients have tumors with muscle bladder layer invasion and poor prognosis at the time of diagnosis. Therefore, the early detection of tumors is required to reduce the mortality rate of BC cases. Since there is a wide geographical incidence variation in BC in Iran, it seems that the ethnic and genetic factors can be the main risk factors among Iranian BC patients.

Results

For the first time, in present review we have summarized all of the reported genes among Iranian BC patients until now which were significantly associated with tumorigenesis. Moreover, we categorized all of the reported genes based on their cell and molecular functions to clarify the genetic and molecular biology of BC among Iranian population.

Conclusion

This review paves the way of determination of a population‐based genetic panel markers for the early detection of BC in this population.

Cancer-testis antigens: An update on their roles in cancer immunotherapy

BACKGROUND

Several recent studies have assessed suitability of tumor antigens for immunotherapy. Based on the restricted expression pattern in somatic tissues, cancer-testis antigens (CTAs) are possible candidates for cancer immunotherapy. These antigens are expressed in various tumors including gastrointestinal, breast, skin and hematologic malignancies.

OBJECTIVES

To find clinical trials utilizing CTAs in cancer patients.

METHODS

We searched PubMed, google scholar and specific websites that registers clinical trials.

RESULTS

A number of clinical trials have been designed to evaluate safety and efficacy of CTA-based treatments. The results of some of them have been promising. In the current literature search, we summarized the clinical trials of CTA-based therapies in cancer patients.

CONCLUSIONS

Based on the availability of different formulations of CTA-based vaccines, future researches should compare efficiency of these modalities.

Extracellular vesicles in urological malignancies: an update

Extracellular vesicles (EVs) have an essential functional role in local tumour progression, metastatic spread and the emergence of drug resistance in bladder, kidney and prostate cancer. Thus, EVs could be diagnostic, prognostic and predictive biomarkers for these malignancies. Virtually all biomolecules (including DNA, mRNA, microRNA, long non-coding RNA, proteins and lipids) packaged into EVs have been tested as biomarkers in blood and urine samples. The results are very heterogeneous, but promising biomarker candidates have been identified. Differing methods of EV isolation, characterization and analysis of their content have been used owing to a lack of international consensus; hence, comparing study results is challenging. Furthermore, validation of potential biomarkers in independent cohorts or prospective trials has rarely been performed. Future efforts to establish EV-derived biomarkers need to adequately address these points. In addition, emerging technologies such as mass spectroscopy and chip-based approaches can identify surface markers specific for cancer-associated EVs and will enable specific separation from blood and urine EVs, which probably will improve their performance as biomarkers. Moreover, EVs could be harnessed as therapeutic drug delivery vehicles for precise and effective anticancer therapy.

TSGA10 overexpression inhibits angiogenesis of HUVECs: A HIF-2α biased perspective

Testis-specific gene antigen 10 (TSGA10) is a protein overexpressed in most cancers; except for some certain types where its expression is reduced. TSGA10 overexpression in HeLa cells has been shown to disrupt hypoxia inducible factor-1α (HIF-1α) axis and exert potent inhibitory effects. Since HIF-1α is structurally and biochemically similar to HIF-2α, TSGA10 is expected to bind HIF-2α and inhibit its function as well. This study elucidated that increased expression of TSGA10 in manipulated human umbilical vein endothelial cells (HUVECs) decreased the proliferation and migration of these cells as affirmed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and wound healing tests, respectively. It also inhibited in vitro angiogenesis of these cells in 3D collagen-cytodex model. Expression levels of genes controlled by HIF-2α including autocrine vascular endothelial growth factor (VEGF) were also assessed using real-time PCR. Our bioinformatic analysis also showed that TSGA10 could bind HIF-2α. Moreover, flow cytometry results indicated a cell cycle arrest in G2/M. Therefore, this study showed that overexpression of TSGA10, as a tumor suppressor gene, in endothelial cells resulted in decreased proliferation, migration and therefore, angiogenic activity of HUVECs. Since angiogenesis is vital for tumor development and metastasis, our findings could be of clinical significance in cancer therapy.

Cellular immune responses against cancer-germline genes in cancers

BACKGROUND

Cancer-germline genes are a class of genes that are normally expressed in testis, trophoblast and few somatic tissues but abnormally expressed in tumor tissues. Their expression signature indicates that they can induce cellular immune responses, thus being applied as targets in cancer immunotherapy.

OBJECTIVES

To obtain the data of cellular immune responses against cancer-germline genes in cancer.

METHODS

We searched PubMed/Medline with the key words cancer-germline antigen, cancer-testis antigen, CD4+ T cell, CD8+ T cell and cancer.

RESULTS

About 40 cancer-germline genes have been shown to induce T cell specific responses in cancer patients. Melanoma, lung and breast cancer are among the mostly assessed cancer types. Several epitopes have been identified which can be used in immunotherapy of cancer.

CONCLUSION

Cellular immune responses against cancer-germline genes are indicative of appropriateness of these genes as therapeutic targets.

Expression analysis of a panel of long non-coding RNAs (lncRNAs) revealed their potential as diagnostic biomarkers in bladder cancer

INTRODUCTION

Long non-coding RNAs (lncRNAs) have fundamental roles in cell migration, proliferation, invasion and metastasis.

METHODS

In the current study, we evaluated expression of a panel of lncRNAs in bladder cancer tissues, adjacent non-cancerous tissues (ANCTs) and normal bladder tissues to evaluate their diagnostic power.

RESULTS

PV1 was down-regulated in tumor tissues compared with both ANCTs and normal controls (Expression ratios of 0.48 and 0.14; P values of 0.4 and <0.001 respectively). HOTAIR, NEAT1, TUG1 and FAS-AS1 were significantly down-regulated in tumor tissues compared with normal controls (Expression ratios of 0.4, 0.68, 0.54 and 0.11; P values of 0.04, 0.02, 0.02 and <0.001 respectively).

CONCLUSION

Combination of transcript levels of seven lncRNAs improved both sensitivity and specificity values to 100%. The current study shows dysregulation of lncRNAs in bladder cancer and implies their role as diagnostic markers in this malignancy.

Humoral immune responses against cancer-testis antigens in human malignancies

BACKGROUND

Cancer-testis antigens (CTAs) are a class of cancer antigens with extensive expression in human cancers. Many researchers have detected antibody responses against these tumor antigens in serum of cancer patients.

OBJECTIVES

To evaluate the relevance of humoral immune responses against CTAs in clinical outcome of cancer patientsMETHODS: We searched PubMed/Medline with the key words cancer-testis antigen, antibody, humoral response and cancer.

RESULTS

Humoral immune responses against CTAs have been detected in several human malignancies including skin, breast, brain and ovarian cancers. Some studies have shown associations between the presence of these responses in patients and patients' survival.

CONCLUSION

Humoral immune responses against CTAs are putative biomarkers for cancer detection and follow-up.