Trends in Research on Exosomes in Cancer Progression and Anticancer Therapy

Global Trends of Exosomes Application in Clinical Trials: A Scoping Review

BACKGROUND

Exosomes, nano-sized extracellular vesicles, have emerged as a promising tool for the diagnosis and treatment of various intractable diseases, including chronic wounds and cancers. As our understanding of exosomes continues to grow, their potential as a powerful therapeutic modality in medicine is also expanding. This systematic review aims to examine the progress of exosome-based clinical trials and provide a comprehensive overview of the therapeutic perspectives of exosomes.

METHODS

This systematic review strictly follows PRISMA guidelines and has been registered in PROSPERO, the International Prospective Register of Systematic Reviews. It encompasses articles from January 2000 to January 2023, sourced from bibliographic databases, with targeted search terms targeting exosome applications in clinical trials. During the screening process, strict inclusion and exclusion criteria were applied, including a focus on clinical trials utilizing different cell-derived exosomes for therapeutic purposes.

RESULTS

Among the 522 publications initially identified, only 10 studies met the stringent eligibility criteria after meticulous screening. The selection process involved systematically excluding duplicates and irrelevant articles to provide a transparent overview.

CONCLUSION

According to our systematic review, exosomes have promising applications in a variety of medical fields, including cell-free therapies and drug delivery systems for treating a variety of diseases, especially cancers and chronic wounds. To ensure safety, potency, and broader clinical applications, further optimization of exosome extraction, loading, targeting, and administration is necessary. While cell-based therapeutics are increasingly utilizing exosomes, this field is still in its infancy, and ongoing clinical trials will provide valuable insights into the clinical utility of exosomes.

Phytochemicals regulate cancer metabolism through modulation of the AMPK/PGC-1α signaling pathway

BACKGROUND

Due to the complex pathophysiological mechanisms involved in cancer progression and metastasis, current therapeutic approaches lack efficacy and have significant adverse effects. Therefore, it is essential to establish novel strategies for combating cancer. Phytochemicals, which possess multiple biological activities, such as antioxidant, anti-inflammatory, antimutagenic, immunomodulatory, antiproliferative, anti-angiogenesis, and antimetastatic properties, can regulate cancer progression and interfere in various stages of cancer development by suppressing various signaling pathways.

METHODS

The current systematic and comprehensive review was conducted based on Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) criteria, using electronic databases, including PubMed, Scopus, and Science Direct, until the end of December 2023. After excluding unrelated articles, 111 related articles were included in this systematic review.

RESULTS

In this current review, the major signaling pathways of cancer metabolism are highlighted with the promising anticancer role of phytochemicals. This was through their ability to regulate the AMP-activated protein kinase (AMPK)/peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α) signaling pathway. The AMPK/PGC-1α signaling pathway plays a crucial role in cancer cell metabolism via targeting energy homeostasis and mitochondria biogenesis, glucose oxidation, and fatty acid oxidation, thereby generating ATP for cell growth. As a result, targeting this signaling pathway may represent a novel approach to cancer treatment. Accordingly, alkaloids, phenolic compounds, terpene/terpenoids, and miscellaneous phytochemicals have been introduced as promising anticancer agents by regulating the AMPK/PGC-1α signaling pathway. Novel delivery systems of phytochemicals targeting the AMPK/PGC-1α pathway in combating cancer are also highlighted in this review.

Unignored intracellular journey and biomedical applications of extracellular vesicles

The intracellular journey of extracellular vesicles (EVs) cannot be ignored in various biological pathological processes. In this review, the biogenesis, biological functions, uptake pathways, intracellular trafficking routes, and biomedical applications of EVs were highlighted. Endosomal escape is a unique mode of EVs release. When vesicles escape from endosomes, they avoid the fate of fusing with lysosomes and being degraded, thus having the opportunity to directly enter the cytoplasm or other organelles. This escape mechanism is crucial for EVs to deliver specific signals or substances. The intracellular trafficking of EVs after endosomal escape is a complex and significant biological process that involves the coordinated work of various cellular structures and molecules. Through the in-depth study of this process, the function and regulatory mechanism of EVs are fully understood, providing new dimensions for future biomedical diagnosis and treatment.

Therapeutic and diagnostic applications of exosomes in colorectal cancer

Exosomes play a key role in colorectal cancer (CRC) related processes. This review explores the various functions of exosomes in CRC and their potential as diagnostic markers, therapeutic targets, and drug delivery vehicles. Exosomal long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) significantly influence CRC progression. Specific exosomal lncRNAs are linked to drug resistance and tumor growth, respectively, highlighting their therapeutic potential. Similarly, miRNAs like miR-21, miR-10b, and miR-92a-3p, carried by exosomes, contribute to chemotherapy resistance by altering signaling pathways and gene expression in CRC cells. The review also discusses exosomes' utility in CRC diagnosis. Exosomes from cancer cells have distinct molecular signatures compared to healthy cells, making them reliable biomarkers. Specific exosomal lncRNAs (e.g., CRNDE-h) and miRNAs (e.g., miR-17-92a) have shown effectiveness in early CRC detection and monitoring of treatment responses. Furthermore, exosomes show promise as vehicles for targeted drug delivery. The potential of mesenchymal stem cell (MSC)-derived exosomes in CRC treatment is also noted, with their role varying from promoting to inhibiting tumor progression. The application of multi-omics approaches to exosome research is highlighted, emphasizing the potential for discovering novel CRC biomarkers through comprehensive genomic, transcriptomic, proteomic, and metabolomic analyses. The review also explores the emerging field of exosome-based vaccines, which utilize exosomes' natural properties to elicit strong immune responses. In conclusion, exosomes represent a promising frontier in CRC research, offering new avenues for diagnosis, treatment, and prevention. Their unique properties and versatile functions underscore the need for continued investigation into their clinical applications and underlying mechanisms.

Therapeutic potential of exosomes in spermatogenesis regulation and male infertility

BACKGROUND

Spermatogenesis is a fundamental process crucial for male reproductive health and fertility. Exosomes, small membranous vesicles released by various cell types, have recently garnered attention for their role in intercellular communication.

OBJECTIVE

This review aims to comprehensively explore the role of exosomes in regulating spermatogenesis, focusing on their involvement in testicular development and cell-to-cell communication.

METHODS

A systematic examination of literature was conducted to gather relevant studies elucidating the biogenesis, composition, and functions of exosomes in the context of spermatogenesis.

RESULTS

Exosomes play a pivotal role in orchestrating the complex signaling networks required for proper spermatogenesis. They facilitate the transfer of key regulatory molecules between different cell populations within the testes, including Sertoli cells, Leydig cells, and germ cells.

CONCLUSION

The emerging understanding of exosome-mediated communication sheds light on novel mechanisms underlying spermatogenesis regulation. Further research in this area holds promise for insights into male reproductive health and potential therapeutic interventions.

Exosome-like Systems: From Therapies to Vaccination for Cancer Treatment and Prevention-Exploring the State of the Art

Cancer remains one of the main causes of death in the world due to its increasing incidence and treatment difficulties. Although significant progress has been made in this field, innovative approaches are needed to reduce tumor incidence, progression, and spread. In particular, the development of cancer vaccines is currently ongoing as both a preventive and therapeutic strategy. This concept is not new, but few vaccines have been approved in oncology. Antigen-based vaccination emerges as a promising strategy, leveraging specific tumor antigens to activate the immune system response. However, challenges persist in finding suitable delivery systems and antigen preparation methods. Exosomes (EXs) are highly heterogeneous bilayer vesicles that carry several molecule types in the extracellular space. The peculiarity is that they may be released from different cells and may be able to induce direct or indirect stimulation of the immune system. In particular, EX-based vaccines may cause an anti-tumor immune attack or produce memory cells recognizing cancer antigens and inhibiting disease development. This review delves into EX composition, biogenesis, and immune-modulating properties, exploring their role as a tool for prevention and therapy in solid tumors. Finally, we describe future research directions to optimize vaccine efficacy and realize the full potential of EX-based cancer immunotherapy.

Stem Cell Extracellular Vesicles as Anti-SARS-CoV-2 Immunomodulatory Therapeutics: A Systematic Review of Clinical and Preclinical Studies

BACKGROUND

COVID-19 rapidly escalated into a worldwide pandemic with elevated infectivity even from asymptomatic patients. Complications can lead to severe pneumonia and acute respiratory distress syndrome (ARDS), which are the main contributors to death. Because of their regenerative and immunomodulatory capacities, stem cells and their derived extracellular vesicles (EVs) are perceived as promising therapies against severe pulmonary conditions, including those associated with COVID-19. Herein, we evaluate the safety and efficacy of stem cell EVs in treating COVID-19 and complicating pneumonia, acute lung injury, and ARDS. We also cover relevant preclinical studies to recapitulate the current progress in stem cell EV-based therapy.

METHODS

Using PubMed, Cochrane Central Register of Controlled Trials, Scopus, and Web of Science, we searched for all English-language published studies (2000-2023) that used stem cell EVs as a therapy for COVID-19, ARDS, or pneumonia. The risk of bias (ROB) was assessed for all studies.

RESULTS

Forty-eight studies met our inclusion criteria. Various-sized EVs derived from different types of stem cells were reported as a potentially safe and effective therapy to attenuate the cytokine storm induced by COVID-19. EVs alleviated inflammation and regenerated the alveolar epithelium by decreasing apoptosis, proinflammatory cytokines, neutrophil infiltration, and M2 macrophage polarization. They also prevented fibrin production and promoted the production of anti-inflammatory cytokines and endothelial cell junction proteins.

CONCLUSION

Similar to their parental cells, stem cell EVs mediate lung tissue regeneration by targeting multiple pathways and thus hold promise in promoting the recovery of COVID-19 patients and improving the survival rate of severely affected patients.

A guide to the expanding field of extracellular vesicles and their release in regulated cell death programs

Homeostasis disruption is visible at the molecular and cellular levels and may often lead to cell death. This vital process allows us to maintain the more extensive system's integrity by keeping the different features (genetic, metabolic, physiologic, and individual) intact. Interestingly, while cells can die in different manners, dying cells still communicate with their environment. This communication was, for a long time, perceived as only driven by the release of soluble factors. However, it has now been reconsidered with the increasing interest in extracellular vesicles (EVs), which are discovered to be released during different regulated cell death programs, with the observation of specific effects. EVs are game changers in the paradigm of cell-cell communication with tremendous implications in fundamental research with regard to noncell autonomous functions, as well as in biomarkers research, all of which are geared toward diagnostic and therapeutic purposes. This review is composed of two main parts. The first is a comprehensive presentation of the state of the art of the EV field at large. In the second part, we focus on EVs discovered to be released during different regulated cell death programs, also known as cell death EVs (cdEVs), and EV-associated specific effects on recipient cells in the context of cell death and inflammation/inflammatory responses.

Tumor Microenvironment Modulation by Cancer-Derived Extracellular Vesicles

The tumor microenvironment (TME) plays an important role in the process of tumorigenesis, regulating the growth, metabolism, proliferation, and invasion of cancer cells, as well as contributing to tumor resistance to the conventional chemoradiotherapies. Several types of cells with relatively stable phenotypes have been identified within the TME, including cancer-associated fibroblasts (CAFs), tumor-associated macrophages (TAMs), neutrophils, and natural killer (NK) cells, which have been shown to modulate cancer cell proliferation, metastasis, and interaction with the immune system, thus promoting tumor heterogeneity. Growing evidence suggests that tumor-cell-derived extracellular vesicles (EVs), via the transfer of various molecules (e.g., RNA, proteins, peptides, and lipids), play a pivotal role in the transformation of normal cells in the TME into their tumor-associated protumorigenic counterparts. This review article focuses on the functions of EVs in the modulation of the TME with a view to how exosomes contribute to the transformation of normal cells, as well as their importance for cancer diagnosis and therapy.

Testing the detoxification power of black cumin oil (Nigella sativa) over cypermethrin insecticide effects in rainbow trout (Oncorhynchus mykiss) at multiple scales

This study investigated the curative effect of black cumin oil (Nigella sativa, NS), which is a phytotherapeutic agent against to cypermethrin (CYP), which is known to have adverse effects on rainbow trout (Oncorhynchus mykiss)'s behavioral changes, oxidative stress-mediated neurotoxicity, hematotoxicity and hepatotoxicity parameters.At the end of the trial period; (i) evaluation of critical swimming speed (Ucrit) (ii) hematology indices [white blood cell (WBC), red blood cell (RBC), hemoglobin (Hgb), hematocrit (Hct), mean cell volume (MCV), mean cell hemoglobin) (MCH), mean cell hemoglobin concentration (MCHC)] (iii) Elucidation of the mechanism of functional damage in brain tissue of O. mykiss by neurological parameter [acetylcholinesterase (AChE)] (iv) Evaluation of oxidative damage in oxidative stress-mediated neurotoxicity and hepatotoxicity in liver, gill and brain tissue of O. mykiss with antioxidant enzymes [(Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), Glutathione (GSH)] and [(detection by means of malondialdehyde (MDA)] (v) Obtaining applicable data in the toxicological field using a multi-biomarker approach to investigate the modulation of NS administration via target markers in the physiological pathway of O. mykiss were aimed.As a result of CYP application, it was determined that the Ucrit value of O. mykiss decreased significantly. It was determined that the changes in the values of RBC, Hgb and Hct, which are among the hematology parameters examined in the blood tissue, were statistically significant (p < 0.05). It was determined that WBC value was inhibited by CYP application and NS tried to make a positive contribution to WBC. It was determined that the AChE activity of O. mykiss in the brain tissue had a statistically significant inhibition in the CYP-treated group (p < 0.05). SOD, CAT, GPx, enzyme activities were found to be inhibited by CYP application and were statistically significant (p < 0.05). Acute toxicity of CYP was determined by antioxidant enzyme biomarkers in gill tissue. In the results obtained; While inhibitions were determined in SOD, CAT, GPx activities compared to the control group, an induction occurred in MDA value.NS administration was noted to be an important modulator of the SOD-CAT system against CYP exposure at both concentrations. Thus, it can be said that it indirectly functions as an effective antioxidant through the NS receptor protein and structurally stimulates the synthesis and activity of antioxidative enzymes under oxidative stress.

Exosome-based delivery strategies for tumor therapy: an update on modification, loading, and clinical application

Malignancy is a major public health problem and among the leading lethal diseases worldwide. Although the current tumor treatment methods have therapeutic effect to a certain extent, they still have some shortcomings such as poor water solubility, short half-life, local and systemic toxicity. Therefore, how to deliver therapeutic agent so as to realize safe and effective anti-tumor therapy become a problem urgently to be solved in this field. As a medium of information exchange and material transport between cells, exosomes are considered to be a promising drug delivery carrier due to their nano-size, good biocompatibility, natural targeting, and easy modification. In this review, we summarize recent advances in the isolation, identification, drug loading, and modification of exosomes as drug carriers for tumor therapy alongside their application in tumor therapy. Basic knowledge of exosomes, such as their biogenesis, sources, and characterization methods, is also introduced herein. In addition, challenges related to the use of exosomes as drug delivery vehicles are discussed, along with future trends. This review provides a scientific basis for the application of exosome delivery systems in oncological therapy.

Engineering HEK293T cell line by lentivirus to produce miR34a-loaded exosomes

BACKGROUND

RNA (ribonucleic acid) antisense is developing as a possible treatment option. As an RNA, miR-34a is involved in P53 function and cancer cell apoptosis. Although the therapeutic applications of miRNAs have several limitations, such as structural instability and susceptibility to nucleases. To resolve these issues, this study aims to apply exosomes as a delivery vehicle for miR-34a.

AIMS

This study aims to create a cell factory to generate miR34a-enriched exosomes. The produced nanoparticles act as a delivery system and improve the structural stability of miR34a.

METHODS

First exosome specific sequences were inserted into miR34a. The resulting miR34a oligonucleotide was transduced HEK293T cells genome with a lentiviral system. In the structure of miR34a oligonucleotide, six nucleotides were substituted to increase its packaging rate into exosomes. To maintain the secondary structure, stability, and expression of the miRNA gene, changes to the miR34a oligonucleotide were made using PCR (polymerase chain reaction) Extension. The forward-34a (5-TGGGGAGAGGCAGGACAGG-3) and Reverse-34a primers (5-TCCGAAGTCCTGGCGTCTCC-3) were used for amplification of the miR34a gene from DNA.

RESULTS

The results confirmed that the changes in miR34a oligonucleotide do not affect its secondary structure. The energy level of the manipulated miR34a oligonucleotide was kept the same compared to the original one. Moreover, the loading of miR34a to the exosomes was increased.

CONCLUSION

Our findings revealed that normal HEK293T did not express miR34a. However, lentiviral transduced miR34a oligonucleotide induced the loading of miR34a into the exosome. Moreover, replacing six nucleic acids in the 3' end of miR34a increased the loading of miR34a to exosome.

Interplay of Extracellular Vesicles and TLR4 Signaling in Hepatocellular Carcinoma Pathophysiology and Therapeutics

Hepatocellular carcinoma (HCC) stands as a significant contributor to global cancer-related mortality. Chronic inflammation, often arising from diverse sources such as viral hepatitis, alcohol misuse, nonalcoholic fatty liver disease (NAFLD), and nonalcoholic steatohepatitis (NASH), profoundly influences HCC development. Within this context, the interplay of extracellular vesicles (EVs) gains prominence. EVs, encompassing exosomes and microvesicles, mediate cell-to-cell communication and cargo transfer, impacting various biological processes, including inflammation and cancer progression. Toll-like receptor 4 (TLR4), a key sentinel of the innate immune system, recognizes both pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs), thereby triggering diverse signaling cascades and pro-inflammatory cytokine release. The intricate involvement of the TLR4 signaling pathway in chronic liver disease and HCC pathogenesis is discussed in this study. Moreover, we delve into the therapeutic potential of modulating the TLR4 pathway using EVs as novel therapeutic agents for HCC. This review underscores the multifaceted role of EVs in the context of HCC and proposes innovative avenues for targeted interventions against this formidable disease.

Unveiling the Yin-Yang Balance of M1 and M2 Macrophages in Hepatocellular Carcinoma: Role of Exosomes in Tumor Microenvironment and Immune Modulation

Hepatocellular carcinoma (HCC) is a primary liver cancer with a high mortality rate and limited treatment options. Recent research has brought attention to the significant importance of intercellular communication in the progression of HCC, wherein exosomes have been identified as critical agents facilitating cell-to-cell signaling. In this article, we investigate the impact of macrophages as both sources and targets of exosomes in HCC, shedding light on the intricate interplay between exosome-mediated communication and macrophage involvement in HCC pathogenesis. It investigates how exosomes derived from HCC cells and other cell types within the tumor microenvironment (TME) can influence macrophage behavior, polarization, and recruitment. Furthermore, the section explores the reciprocal interactions between macrophage-derived exosomes and HCC cells, stromal cells, and other immune cells, elucidating their role in tumor growth, angiogenesis, metastasis, and immune evasion. The findings presented here contribute to a better understanding of the role of macrophage-derived exosomes in HCC progression and offer new avenues for targeted interventions and improved patient outcomes.

Exosomal PIK3CB promotes PD-L1 expression and malignant transformation in esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC), which accounts for 90% of esophageal carcinomas, seriously endangers human health. Worse still, the 5-year overall survival of ESCC is approximately 20%. Elucidation of the potential mechanism and exploration of promising drugs for ESCC are urgently needed. In this study, a high level of exosomal PIK3CB protein was found in the plasma of ESCC patients, which might indicate a poor prognosis. Moreover, a significant Pearson's correlation was observed at the protein level between exosomal PIK3CB and exosomal PD-L1. Further study revealed that cancer cell-intrinsic and exosome-derived PIK3CB promoted the transcriptional activity of the PD-L1 promoter in ESCC cells. Moreover, treatment with exosomes with lower levels of exosomal PIK3CB decreased the protein level of the mesenchymal marker β-catenin while increasing that of the epithelial marker claudin-1, indicating the potential regulation of epithelial-mesenchymal transition. Consequently, the migratory ability and cancer stemness of ESCC cells and the growth of tumors formed by ESCC cells were decreased with the downregulation of exosomal PIK3CB. Therefore, exosomal PIK3CB plays an oncogenic role by promoting PD-L1 expression and malignant transformation in ESCC. This study may provide new insight into the inherent biological aggressiveness and the poor response to currently available therapies of ESCC. Exosomal PIK3CB may be a promising target for the diagnosis and therapy of ESCC in the future.

Extracellular vesicles as next generation immunotherapeutics

Extracellular vesicles (EVs) function as a mode of intercellular communication and molecular transfer to elicit diverse biological/functional response. Accumulating evidence has highlighted that EVs from immune, tumour, stromal cells and even bacteria and parasites mediate the communication of various immune cell types to dynamically regulate host immune response. EVs have an innate capacity to evade recognition, transport and transfer functional components to target cells, with subsequent removal by the immune system, where the immunological activities of EVs impact immunoregulation including modulation of antigen presentation and cross-dressing, immune activation, immune suppression, and immune surveillance, impacting the tumour immune microenvironment. In this review, we outline the recent progress of EVs in immunorecognition and therapeutic intervention in cancer, including vaccine and targeted drug delivery and summarise their utility towards clinical translation. We highlight the strategies where EVs (natural and engineered) are being employed as a therapeutic approach for immunogenicity, tumoricidal function, and vaccine development, termed immuno-EVs. With seminal studies providing significant progress in the sequential development of engineered EVs as therapeutic anti-tumour platforms, we now require direct assessment to tune and improve the efficacy of resulting immune responses - essential in their translation into the clinic. We believe such a review could strengthen our understanding of the progress in EV immunobiology and facilitate advances in engineering EVs for the development of novel EV-based immunotherapeutics as a platform for cancer treatment.

Exosome-like systems: Nanotechnology to overcome challenges for targeted cancer therapies

Exosomes are natural extracellular nanovesicles (30-150 nm in diameter) with the ability to interact with and be taken up by specific cells. They are being explored as delivery systems and imaging agents for biomedical purposes owing to their biocompatibility, biostability in extracellular biofluids, and organotropic properties. However, their usefulness, efficacy, and clinical application are limited by certain critical parameters, including the need for more robust and reproducible manufacturing processes, characterization, quality control assessment, and clinical studies. Recently, exosome-like systems have emerged as alternatives for overcoming the limitations of natural exosomes. These systems are based on surface engineering approaches and nanoscale platforms that offer a deeper understanding and allow for more exhaustive standardization compared with natural exosomes. By combining the latest knowledge related to exosome research with the most promising developments in nanotechnology, exosome-like systems can be developed as a competitive approach for innovative targeted anti-cancer therapies. This review aims to provide a critical overview of the latest advances in designing and testing innovative exosome-like systems and the most promising modalities that can be translated into the clinic. Future perspectives and challenges in this field are discussed.

Exosome-based cancer vaccine for prevention of lung cancer

Background

Our earlier work has shown that a unique stem cell-based vaccine that comprises of murine embryonic stem cells (ESCs) and murine fibroblasts expressing the immunostimulant granulocyte-macrophage colony stimulating factor (GM-CSF) successfully protects mice from the outgrowth of an implantable form of murine lung cancer. The use of live ESCs raises the potential risks of inducing teratomas and autoimmunity. We have attempted to improve the safety and utility of this prophylactic vaccine by employing exosomes derived from murine ESCs engineered to produce GM-CSF (ES-exo/GM-CSF vaccine).

Methods

We have previously reported that ES-exo/GM-CSF immunization does protect mice from the outgrowth of an implantable form of murine lung cancer. Here, we have investigated the cancer prevention efficacy of ES-exo/GM-CSF vaccine in an experimental metastasis model of murine lung cancer, in which Lewis lung carcinoma (LLC) cells were administered into female C57BL/6 mice (8 weeks of age) through tail vein injection and subsequently LLC tumors were established in lungs.

Results

Our objective is to test the anti-cancer efficacy of ES-exo/GM-CSF vaccine in a mouse model of metastatic lung cancer. Our studies indicate that vaccination of mice with ES-exo/GM-CSF vaccine inhibited the growth of metastatic lung tumors. ES-exo/GM-CSF vactionation reduced lung tumor burden from 1.86% in non-vaccinated, LLC-challenged mice to 0.036% in corresponding vacinnated mice. Importantly, control exosomes without GM-CSF failed to provide protection against metastasized pulmonary tumors. The efficacy of ES-exo/GM-CSF vaccination was associated with a decrease in the frequencies of tumor-infiltrating immunosuppressive immune cells, including T regulatory cells, myeloid derived suppressor cells (MDSCs) and tumor-associated macrophages, as well as an increase in effector cytokine production from intra-tumoral CD8+ T cells.

Conclusions

Overall, our research provides a novel strategy for developing a cell-free prophylactic vaccine against lung tumors.

Curcumin mediated dendritic cell maturation by modulating cancer associated fibroblasts-derived exosomal miRNA-146a

BACKGROUND

Though cancer associated fibroblasts (CAFs), being a main component of tumor microenvironment (TME), are known to modulate immune response through secretion of various growth hormones, exosomes carrying miRNAs and cytokines; their effect on dendritic cells (DCs) are yet to be elucidated. Thus, aim of this study was to assess the effect of miRNAs and cytokines released by lung-CAFs and to evaluate immunomodulatory potential of curcumin on DC maturation through modulating their TME.

MATERIAL AND METHODS

To check the effect of CAFs derived exosomes on DC maturation, we cultured imDCs in the presence of CAFs derived conditioned media (CAFs-CM) and characterized by the presence of maturation markers CD80, CD83, CD86 and CTLA4 using qRT-PCR. Additionally, expression of miR-221, miR-222, miR-155, miR-142-3p and miR-146a was assessed to evaluate the role of epigenetic regulators on DC maturation. Likewise, cytokine profiling of CAFs-CM as well as CAFs-CM treated with curcumin was also conducted using ELISA.

RESULTS

Results revealed the generation of regulatory DCs which were characterized by decreased expression of maturation markers in the presence of CAFs-CM. In addition, such DCs showed higher expression of epigenetic regulator miR-146a which was positively correlated with increased expression of anti-inflammatory cytokines like IL-6, IL-10, TGF-β and decreased expression of TNF-α (pro-inflammatory). Moreover, curcumin had the potential to convert regulatory DCs generated by CAFs into mDCs, which were characterized by high expression of co-stimulatory molecules, low expression of CTLA4, lower levels of immune suppressive cytokines production and lower levels of miR-146a.

CONCLUSION

Collectively, these findings provide insight into understanding the immunomodulatory role of curcumin in targeting CAFs and modulating TME, thus enhancing antitumor immune response in DC based therapy.

Drug Resistance: The Role of Exosomal miRNA in the Microenvironment of Hematopoietic Tumors

Extracellular vesicles (EVs), including exosomes, have an important role thanks to their ability to communicate and exchange information between tumor cells and the tumor microenvironment (TME), and have also been associated with communicating anti-cancer drug resistance (DR). The increase in proliferation of cancer cells alters oxygen levels, which causes hypoxia and results in a release of exosomes by the cancer cells. In this review, the results of studies examining the role of exosomal miRNA in DR, and their mechanism, are discussed in detail in hematological tumors: leukemia, lymphoma, and multiple myeloma. In conclusion, we underline the exosome's function as a possible drug delivery vehicle by understanding its cargo. Engineered exosomes can be used to be more specific for personalized therapy.

The Convergence of FTIR and EVs: Emergence Strategy for Non-Invasive Cancer Markers Discovery

In conjunction with imaging analysis, pathology-based assessments of biopsied tissue are the gold standard for diagnosing solid tumors. However, the disadvantages of tissue biopsies, such as being invasive, time-consuming, and labor-intensive, have urged the development of an alternate method, liquid biopsy, that involves sampling and clinical assessment of various bodily fluids for cancer diagnosis. Meanwhile, extracellular vesicles (EVs) are circulating biomarkers that carry molecular profiles of their cell or tissue origins and have emerged as one of the most promising biomarkers for cancer. Owing to the biological information that can be obtained through EVs' membrane surface markers and their cargo loaded with biomolecules such as nucleic acids, proteins, and lipids, EVs have become useful in cancer diagnosis and therapeutic applications. Fourier-transform infrared spectroscopy (FTIR) allows rapid, non-destructive, label-free molecular profiling of EVs with minimal sample preparation. Since the heterogeneity of EV subpopulations may result in complicated FTIR spectra that are highly diverse, computational-assisted FTIR spectroscopy is employed in many studies to provide fingerprint spectra of malignant and non-malignant samples, allowing classification with high accuracy, specificity, and sensitivity. In view of this, FTIR-EV approach carries a great potential in cancer detection. The progression of FTIR-based biomarker identification in EV research, the rationale of the integration of a computationally assisted approach, along with the challenges of clinical translation are the focus of this review.

Novel Roles of Nanog in Cancer Cells and Their Extracellular Vesicles

The use of extracellular vesicle (EV)-based vaccines is a strategically promising way to prevent cancer metastasis. The effective roles of immune cell-derived EVs have been well understood in the literature. In the present paper, we focus on cancer cell-derived EVs to enforce, more thoroughly, the use of EV-based vaccines against unexpected malignant cells that might appear in poor prognostic patients. As a model of such a cancer cell with high malignancy, Nanog-overexpressing melanoma cell lines were developed. As expected, Nanog overexpression enhanced the metastatic potential of melanomas. Against our expectations, a fantastic finding was obtained that determined that EVs derived from Nanog-overexpressing melanomas exhibited a metastasis-suppressive effect. This is considered to be a novel role for Nanog in regulating the property of cancer cell-derived EVs. Stimulated by this result, the review of Nanog's roles in various cancer cells and their EVs has been updated once again. Although there was no other case presenting a similar contribution by Nanog, only one case suggested that NANOG and SOX might be better prognosis markers in head and neck squamous cell carcinomas. This review clarifies the varieties of Nanog-dependent phenomena and the relevant signaling factors. The information summarized in this study is, thus, suggestive enough to generate novel ideas for the construction of an EV-based versatile vaccine platform against cancer metastasis.

Role of motor proteins in human cancers

Motor proteins include several protein families (Kinesin, Dynein and Myosin) responsible for intracellular transport, intercellular communication, among other functions. In cancer cells, motor proteins along with microtubules (MT) and other tubulin and actin structures, are crucial for cell proliferation and invasion. The cBioPortal platform for Cancer Genomics database was queried for solid cancers in a combined cohort of 9204 patients with complete cancer genomics data. To assess the importance of motor proteins in cancer, copy number alterations (CNAs) and survival rates were analyzed in the combined dataset. Kinesin, Dynein, and Myosin families showed CNAs in 47%, 49%, and 57 % of patients, respectively, in at least one of their members. Survival analysis showed that CNAs in Kinesin and Dynein, families' genes in the same patients were significantly correlated to decreased overall survival. These results added more evidence to previous literature highlighting the importance of motor proteins as a target in cancer therapy. Kinesin inhibitors could act by several mechanisms such as inhibiting spindle assembly or centrosome separation during mitosis, leading to cell cycle arrest and eventually apoptosis. Dynein inhibitors modulate Dynein's activity and MT binding, inhibiting cell proliferation and invasion. Myosin inhibitors act by stabilizing MT, inducing cell cycle arrest and inhibiting invasiveness. Increasing the specificity of motor proteins targeting drugs could improve cancer therapy and patient survival.

Current advances in the use of exosomes, liposomes, and bioengineered hybrid nanovesicles in cancer detection and therapy

Three major approaches of cancer therapy can be enunciated as delivery of biotherapeutics, tumor image analysis, and immunotherapy. Liposomes, artificial fat bubbles, are long known for their capacity to encapsulate a diverse range of bioactive molecules and release the payload in a sustained, stimuli-responsive manner. They have already been widely explored as a delivery vehicle for therapeutic drugs as well as imaging agents. They are also extensively being used in cancer immunotherapy. On the other hand, exosomes are naturally occurring nanosized extracellular vesicles that serve an important role in cell-cell communication. Importantly, the exosomes also have proven their capability to carry an array of active pharmaceuticals and diagnostic molecules to the tumor cells. Exosomes, being enriched with tumor antigens, have numerous immunomodulatory effects. Much to our intrigue, in recent times, efforts have been directed toward developing smart, bioengineered, exosome-liposome hybrid nanovesicles, which are augmented by the benefits of both vesicular systems. This review attempts to summarize the contemporary developments in the use of exosome and liposome toward cancer diagnosis, therapy, as a vehicle for drug delivery, diagnostic carrier for tumor imaging, and cancer immunotherapy. We shall also briefly reflect upon the recent advancements of the exosome-liposome hybrids in cancer therapy. Finally, we put forward future directions for the use of exosome/liposome and/or hybrid nanocarriers for accurate diagnosis and personalized therapies for cancers.

Plasma Exchange May Enhance Antitumor Effects by Removal of Soluble Programmed Death-Ligand 1 and Extracellular Vesicles: Preliminary Study

The antitumor effect of antibody-drug conjugates (ADC) is the main factor in achieving cures. Although the mechanism of tumor resistance to treatment is multifaceted, tumor-derived extracellular vesicles (T-EVs) have been implicated as contributing to the attenuation of ADC therapeutic efficacy. Thus, strategies to eliminate T-EVs are highly promising for overcoming drug resistance. Here we demonstrate plasma exchange therapy to remove T-EVs, decreasing their amount in vitro by 75%. Although trastuzumab emtansine (T-DM1) treatment alone was effective in our rat tumor model, the combination therapy of T-DM1 and T-EV filtration achieved early tumor shrinkage. Our results indicate that T-EV filtration plus ADC is a promising strategy for overcoming drug resistance.

Identification of Biomarkers Associated with Liver Metastasis Progression from Colorectal Cancer Using Exosomal RNA Profiling

This study aimed to identify novel biomarkers for metastatic colorectal cancer progression using exosomal RNA expression profiling. The exosomal RNA expression profiles of 54 patients with mCRC were investigated. Exosomal RNA profiling was performed at the time of relapse immediately before metastasectomy and cancer recurrence or progression after metastasectomy. The up- and down-regulated RNA expression profiles were screened and analyzed using H-cluster, principle component analysis and gene ontology. The tissue expression profile of the liver metastases was compared with the GSE 41258 set using GSEA tools. We identified two distinctive biological process gene sets (IFNA and PCDB families) related to metastatic progression. The interferon-α response gene set was enriched, especially when the tumor volume was ≥1 cm3. CXCL10, CXCL11 and SAMD 9 mRNA were highly expressed in the plasma exosome samples of patients with mCRC to the liver. Furthermore, high expression of CXCL10 but not CXCL11 or SAMD9 was associated with a poor prognosis and shorter progression-free survival. Conclusions: Cancer-derived exosomal CXCL10 may be a novel biomarker for liver metastasis of mCRC and a potential target for the prevention and treatment of mCRC with liver metastasis.

The role and application of small extracellular vesicles in breast cancer

Breast cancer (BC) is the most common malignancy and the leading cause of cancer-related deaths in women worldwide. Currently, patients’ survival remains a challenge in BC due to the lack of effective targeted therapies and the difficult condition of patients with higher aggressiveness, metastasis and drug resistance. Small extracellular vesicles (sEVs), which are nanoscale vesicles with lipid bilayer envelopes released by various cell types in physiological and pathological conditions, play an important role in biological information transfer between cells. There is growing evidence that BC cell-derived sEVs may contribute to the establishment of a favorable microenvironment that supports cancer cells proliferation, invasion and metastasis. Moreover, sEVs provide a versatile platform not only for the diagnosis but also as a delivery vehicle for drugs. This review provides an overview of current new developments regarding the involvement of sEVs in BC pathogenesis, including tumor proliferation, invasion, metastasis, immune evasion, and drug resistance. In addition, sEVs act as messenger carriers carrying a variety of biomolecules such as proteins, nucleic acids, lipids and metabolites, making them as potential liquid biopsy biomarkers for BC diagnosis and prognosis. We also described the clinical applications of BC derived sEVs associated MiRs in the diagnosis and treatment of BC along with ongoing clinical trials which will assist future scientific endeavors in a more organized direction.

Tumor-derived small extracellular vesicles: potential roles and mechanism in glioma

Small extracellular vesicles (SEVs) are extracellular vesicles containing DNA, RNA, and proteins and are involved in intercellular communication and function, playing an essential role in the growth and metastasis of tumors. SEVs are present in various body fluids and can be isolated and extracted from blood, urine, and cerebrospinal fluid. Under both physiological and pathological conditions, SEVs can be released by some cells, such as immune, stem, and tumor cells, in a cytosolic manner. SEVs secreted by tumor cells are called tumor-derived exosomes (TEXs) because of their origin in the corresponding parent cells. Glioma is the most common intracranial tumor, accounting for approximately half of the primary intracranial tumors, and is characterized by insidious onset, high morbidity, and high mortality rate. Complete removal of tumor tissues by surgery is difficult. Chemotherapy can improve the survival quality of patients to a certain extent; however, gliomas are prone to chemoresistance, which seriously affects the prognosis of patients. In recent years, TEXs have played a vital role in the occurrence, development, associated immune response, chemotherapy resistance, radiation therapy resistance, and metastasis of glioma. This article reviews the role of TEXs in glioma progression, drug resistance, and clinical diagnosis.

Role of microRNAs in B-Cell Compartment: Development, Proliferation and Hematological Diseases

B-cell development is a very orchestrated pathway that involves several molecules, such as transcription factors, cytokines, microRNAs, and also different cells. All these components maintain the ideal microenvironment and control B-cell differentiation. MicroRNAs are small non-coding RNAs that bind to target mRNA to control gene expression. These molecules could circulate in the body in a free form, protein-bounded, or encapsulated into extracellular vesicles, such as exosomes. The comprehension of the role of microRNAs in the B-cell development was possible based on microRNA profile of each B-cell stage and functional studies. Herein, we report the knowledge about microRNAs in the B-cell the differentiation, proliferation, and also in hematological malignancies.

Role of exosomes in lung cancer: A comprehensive insight from immunomodulation to theragnostic applications

Exosomes are 30 to 150 nm-diameter lipid bilayer-enclosed extracellular vesicles that enable cell-to-cell communication through secretion and uptake. The exosomal cargoes contain RNA, lipids, proteins, and metabolites which can be delivered to recipient cells in vivo. In a healthy lung, exosomes facilitate interaction between adaptive and innate immunity and help maintain normal lung physiology. However, tumor-derived exosomes in lung cancer (LC) can, on the other hand, restrict immune cell proliferation, cause apoptosis in activated CD8+ T effector cells, reduce natural killer cell activity, obstruct monocyte differentiation, and promote proliferation of myeloid-derived suppressor and regulatory T cells. In addition, exosomes in the tumor microenvironment may also play a critical role in cancer progression and the development of drug resistance. In this review, we aim to comprehensively examine the current updates on the role of exosomes in lung carcinogenesis and their potential application as a diagnostic, prognostic, and therapeutic tool in lung cancer.

The Promising Role of Natural Exosomal Nanoparticles in Cancer Chemoimmunotherapy

Exosomal nanoparticles are cell-derived nano-sized vesicles in the size range of 30-150nm formed by the inward infolding of the cell membrane. They are encased in a lipid bilayer membrane and contain various proteins and nucleic acids according to the characteristics of their parent cell. They are involved in intercellular communication. Their specific structural and inherent properties are helpful in therapeutics and as biomarkers in diagnostics. Since they are biomimetic, these small-sized nanoparticles pose many advantages if used as a drug carrier vehicle. In cancer, the exosomal nanoparticles have both stimulatory and inhibitory activity towards immune responses; hence, they are used in immunotherapy. They can also carry chemotherapeutic agents to the target site minimizing their targetability concerns. Chemoimmunotherapy (CIT) is a synergistic approach in which chemotherapy and immunotherapy are utilized to benefit each other. Exosomal nanoparticles (NPs) are essential in delivering CIT agents into tumor tissues. Most advanced studies in CIT take place in the stimulator of interferon genes (STING) signaling pathway, where the STING activation supported by chemotherapy-induced an increase in immune surveillance through the help of exosomal NPs. Dendritic cell(DC) derived exosomes, as well as Mesenchymal stem cells (MSC), are abundantly used in immunotherapy, and hence their support can be used in chemoimmunotherapy (CIT) for multifaceted benefits.

The therapeutic effect of exosomes from mesenchymal stem cells on colorectal cancer: Toward cell-free therapy

Colorectal cancer (CRC) is known for its high mortality rate and affects more men than women. The treatment requires invasive surgical interventions, however, the progression of CRC metastasis is difficult to control in most cases. Mesenchymal stem cells (MSCs) with their outstanding characteristics have been widely used in the treatment of degenerative diseases as well as cancers. They affect the tumor microenvironment through either cell-cell interactions or communications with their secretome. While stem cells may represent a dual role in tumor proliferation and progression, exosomes have attracted much attention as a cell-free therapy in CRC treatment. Exosomes derived from native or genetically modified MSCs, as well as exosomal microRNAs (miRNAs), have been evaluated on CRC progression. Moreover, MSC-derived exosomes have been used as a carrier to deliver anticancer agents in colorectal cancer. In this review, we overview and discuss the current knowledge in both stem cell-based and cell-free exosome therapy of CRC.

Exosomes: Insights and therapeutic applications in cancer

Cancer refers to the division of abnormal cells at an uncontrollable rate that possesses the ability to infiltrate and destroy normal tissues. It frequently spreads to normal tissues throughout the body, a condition known as metastasis, which is a significant concern. It is the second leading cause of mortality globally and treatment therapy can assist in improving survival rates. Exosomes are the extracellular vesicles secreted by several cells that act as messengers between cells. When engineered, exosomes act as promising drug delivery vehicles that help achieve targeted action at the tumour site and reduce the limitations of conventional treatments such as castration, chemotherapy, radiation, etc. The present review provides an overview of exosomes, the biogenesis, sources, isolation methods and characterization. The current status and applications of chemotherapeutic agents loaded, engineered exosomes in cancer treatment were convoluted.

Emerging role of exosomes in cancer progression and tumor microenvironment remodeling

Cancer is one of the leading causes of death worldwide, and the factors responsible for its progression need to be elucidated. Exosomes are structures with an average size of 100 nm that can transport proteins, lipids, and nucleic acids. This review focuses on the role of exosomes in cancer progression and therapy. We discuss how exosomes are able to modulate components of the tumor microenvironment and influence proliferation and migration rates of cancer cells. We also highlight that, depending on their cargo, exosomes can suppress or promote tumor cell progression and can enhance or reduce cancer cell response to radio- and chemo-therapies. In addition, we describe how exosomes can trigger chronic inflammation and lead to immune evasion and tumor progression by focusing on their ability to transfer non-coding RNAs between cells and modulate other molecular signaling pathways such as PTEN and PI3K/Akt in cancer. Subsequently, we discuss the use of exosomes as carriers of anti-tumor agents and genetic tools to control cancer progression. We then discuss the role of tumor-derived exosomes in carcinogenesis. Finally, we devote a section to the study of exosomes as diagnostic and prognostic tools in clinical courses that is important for the treatment of cancer patients. This review provides a comprehensive understanding of the role of exosomes in cancer therapy, focusing on their therapeutic value in cancer progression and remodeling of the tumor microenvironment.

Exosomes as Theranostic Targets: Implications for the Clinical Prognosis of Aggressive Cancers

Exosomes are extracellular vesicles produced by various cell types and extensively distributed in physiological fluids. Because of their significant role in cancer progression, they have been a focal point for the novel cancer therapy approach. Exosomes are highly efficient at transporting proteins, RNAs, and small drugs into cancer cells for therapeutic purposes. In addition to their prominent role as potential biomarkers for transporting targeted information from their progenitor cells, exosomes have also emerged as a new avenue for developing more effective clinical diagnostics and therapeutic techniques, also known as exosome theranostics. Lipids, proteins, and nucleic acids transported by exosomes were investigated as potential biomarkers for cancer diagnosis, prognosis, and future cancer treatment targets. The unique mechanism of exosomes and their therapeutic as well as diagnostic uses, also known as theranostic applications of exosomes in malignancies, are discussed in this review.

Resistance to Gemcitabine in Pancreatic Ductal Adenocarcinoma: A Physiopathologic and Pharmacologic Review

Pancreatic ductal adenocarcinoma (PDAC) is a very aggressive tumor with a poor prognosis and inadequate response to treatment. Many factors contribute to this therapeutic failure: lack of symptoms until the tumor reaches an advanced stage, leading to late diagnosis; early lymphatic and hematic spread; advanced age of patients; important development of a pro-tumoral and hyperfibrotic stroma; high genetic and metabolic heterogeneity; poor vascular supply; a highly acidic matrix; extreme hypoxia; and early development of resistance to the available therapeutic options. In most cases, the disease is silent for a long time, andwhen it does become symptomatic, it is too late for ablative surgery; this is one of the major reasons explaining the short survival associated with the disease. Even when surgery is possible, relapsesare frequent, andthe causes of this devastating picture are the low efficacy ofand early resistance to all known chemotherapeutic treatments. Thus, it is imperative to analyze the roots of this resistance in order to improve the benefits of therapy. PDAC chemoresistance is the final product of different, but to some extent, interconnected factors. Surgery, being the most adequate treatment for pancreatic cancer and the only one that in a few selected cases can achieve longer survival, is only possible in less than 20% of patients. Thus, the treatment burden relies on chemotherapy in mostcases. While the FOLFIRINOX scheme has a slightly longer overall survival, it also produces many more adverse eventsso that gemcitabine is still considered the first choice for treatment, especially in combination with other compounds/agents. This review discusses the multiple causes of gemcitabine resistance in PDAC.

Exosome Processing and Characterization Approaches for Research and Technology Development

Exosomes are extracellular vesicles that share components of their parent cells and are attractive in biotechnology and biomedical research as potential disease biomarkers as well as therapeutic agents. Crucial to realizing this potential is the ability to manufacture high-quality exosomes; however, unlike biologics such as proteins, exosomes lack standardized Good Manufacturing Practices for their processing and characterization. Furthermore, there is a lack of well-characterized reference exosome materials to aid in selection of methods for exosome isolation, purification, and analysis. This review informs exosome research and technology development by comparing exosome processing and characterization methods and recommending exosome workflows. This review also provides a detailed introduction to exosomes, including their physical and chemical properties, roles in normal biological processes and in disease progression, and summarizes some of the on-going clinical trials.

Understanding the Correlation between Metabolic Regulator SIRT1 and Exosomes with CA-125 in Ovarian Cancer: A Clinicopathological Study

Background

Ovarian cancer (OvCa), the deadliest gynaecological malignancy, is associated with poor prognosis and high mortality rate. Ovarian cancer has been related with CA-125 and metabolic reprogramming by SIRT1 leading to metastasis with the involvement of exosomes.

Methods

Clinicopathological data of OvCa patients were collected to perform the analysis. Patients' samples were collected during surgery for immunohistochemistry and flow cytometric analysis of SIRT1, HIF-1α, exosomal markers (CD81 and CD63), ki-67, and PAS staining for glycogen deposition. Adjacent normal and tumor tissues were collected as per the CA-125 levels.

Results

CA-125, a vital diagnostic marker, has shown significant correlation with body mass index (BMI) (P = 0.0153), tumor type (P = 0.0029), ascites level, ascites malignancy, degree of dissemination, tumor differentiation, FIGO stage, TNM stage, laterality, and tumor size at P < 0.0001. Since significant correlation was associated with BMI and degree of dissemination, as disclosed by IHC analysis, metabolic marker SIRT1 (P = 0.0003), HIF-1α (P < 0.0001), exosomal marker CD81 (P < 0.0001), ki-67 status (P = 0.0034), and glycogen deposition (P <0.0001) were expressed more in tumor tissues as compared to the normal ones. ROC analysis of CA-125 had shown 327.7 U/ml has the best cutoff point with 82.4% sensitivity and specificity of 52.3%. In addition, Kaplan-Meier plots of CA-125 (P < 0.0001), BMI (P = 0.001), degree of dissemination (P < 0.0001), and ascites level (P <0.0001) reflected significant correlation with overall survival (OS). Upon multivariate Cox-regression analysis for overall survival (OS), BMI (P = 0.008, HR 1.759, 95% CI 1.156-2.677), ascites malignancy (P = 0.032, HR 0.336, 95% CI 0.124-0.911), and degree of dissemination (P = 0.004, HR 1.994, 95% CI 1.251-3.178) were significant proving to be independent indicators of the disease.

Conclusion

Clinicopathological parameters like BMI, degree of dissemination, and ascites level along with CA-125 can be prognostic factors for the disease. Levels of CA-125 can depict the metabolic and metastatic factors. Thus, by targeting SIRT1 and assessing exosomal concentrations to overcome metastasis and glycogen deposition, individualized treatment strategy could be designed. In-depth studies are still required.

Emerging Nanotherapeutic Approaches to Overcome Drug Resistance in Cancers with Update on Clinical Trials

A key issue with modern cancer treatments is the emergence of resistance to conventional chemotherapy and molecularly targeted medicines. Cancer nanotherapeutics were created in order to overcome the inherent limitations of traditional chemotherapeutics. Over the last few decades, cancer nanotherapeutics provided unparalleled opportunities to understand and overcome drug resistance through clinical assessment of rationally designed nanoparticulate delivery systems. In this context, various design strategies such as passive targeting, active targeting, nano-drug, and multimodal nano-drug combination therapy provided effective cancer treatment. Even though cancer nanotherapy has made great technological progress, tumor biology complexity and heterogeneity and a lack of comprehensive knowledge of nano-bio interactions remain important roadblocks to future clinical translation and commercialization. The current developments and advancements in cancer nanotherapeutics employing a wide variety of nanomaterial-based platforms to overcome cancer treatment resistance are discussed in this article. There is also a review of various nanotherapeutics-based approaches to cancer therapy, including targeting strategies for the tumor microenvironment and its components, advanced delivery systems for specific targeting of cancer stem cells (CSC), as well as exosomes for delivery strategies, and an update on clinical trials. Finally, challenges and the future perspective of the cancer nanotherapeutics to reverse cancer drug resistance are discussed.

Tumor microenvironment manipulates chemoresistance in ovarian cancer (Review)

Ovarian cancer (OC) is the leading cause of mortality among the various types of gynecological cancer, and >75% of the cases are diagnosed at a late stage. Although platinum‑based chemotherapy is able to help the majority of patients to achieve remission, the disease frequently recurs and acquires chemoresistance, resulting in high mortality rates. The complexity of OC therapy is not solely governed by the intrinsic characteristics of the OC cells (OCCs) themselves, but is also largely dependent on the dynamic communication between OCCs and various components of their surrounding microenvironment. The present review attempts to describe the mutual interplay between OCCs and their surrounding microenvironment. Tumor‑associated macrophages (TAMs) and cancer‑associated fibroblasts (CAFs) are the most abundant stromal cell types in OC. Soluble factors derived from CAFs steadily nourish both the OCCs and TAMs, facilitating their proliferation and immune evasion. ATP binding cassette transporters facilitate the extrusion of cytotoxic molecules, eventually promoting cell survival and multidrug resistance. Extracellular vesicles fulfill their role as genetic exchange vectors, transferring cargo from the donor cells to the recipient cells and propagating oncogenic signaling. A greater understanding of the vital roles of the tumor microenvironment will allow researchers to be open to the prospect of developing therapeutic approaches for combating OC chemoresistance.

Exosomes and Other Extracellular Vesicles with High Therapeutic Potential: Their Applications in Oncology, Neurology, and Dermatology

Until thirty years ago, it was believed that extracellular vesicles (EVs) were used to remove unnecessary compounds from the cell. Today, we know about their enormous potential in diagnosing and treating various diseases. EVs are essential mediators of intercellular communication, enabling the functional transfer of bioactive molecules from one cell to another. Compared to laboratory-created drug nanocarriers, they are stable in physiological conditions. Furthermore, they are less immunogenic and cytotoxic compared to polymerized vectors. Finally, EVs can transfer cargo to particular cells due to their membrane proteins and lipids, which can implement them to specific receptors in the target cells. Recently, new strategies to produce ad hoc exosomes have been devised. Cells delivering exosomes have been genetically engineered to overexpress particular macromolecules, or transformed to release exosomes with appropriate targeting molecules. In this way, we can say tailor-made therapeutic EVs are created. Nevertheless, there are significant difficulties to solve during the application of EVs as drug-delivery agents in the clinic. This review explores the diversity of EVs and the potential therapeutic options for exosomes as natural drug-delivery vehicles in oncology, neurology, and dermatology. It also reflects future challenges in clinical translation.

Anti-Metastatic Function of Extracellular Vesicles Derived from Nanog-Overexpressing Melanoma

A metastatic melanoma cell line B16-F10 (F10) was modified to a more undifferentiated state by Nanog overexpression. The produced cell line Nanog⁺F10 showed a higher metastatic potential than F10. Instead of whole cells, the extracellular vesicles (EVs) therefrom were investigated about their possible role as an autovaccine against metastasis. EVs from Nanog⁺F10 cells (Nanog⁺F10-EVs) could suppress the metastasis, contrasting the EVs from less metastatic F10 cells (F10-EVs) enhanced metastasis. The involvement of TGF-β1 in the role of Nanog⁺F10-EVs was analyzed, as TGF-β1 was a secretory cytokine being affected most intensively by Nanog overexpression. It was suggested to be crucial that the TGF-β1 concentration in Nanog⁺F10-EVs should be as low as 1.6 pg/μg for its metastasis-suppressive role. In response to Nanog⁺F10-EVs, immunoreaction was observed in liver, indicating the specific decrease in the number of tumor-promotive CD163-positive macrophages. These indicate a possibility of Nanog⁺F10-EVs as a novel autovaccine candidate against melanoma metastasis.

Hyperthermia promotes exosome secretion by regulating Rab7b while increasing drug sensitivity in adriamycin-resistant breast cancer

PURPOSE

To investigate the mechanism through which hyperthermia promotes exosome secretion and drug sensitivity in adriamycin-resistant breast cancer.

MATERIALS AND METHODS

We first evaluated the effect of hyperthermia on adriamycin-resistant breast cancer viability and used transmission electron microscopy, nanoparticle tracking analysis, and a bicinchoninic acid kit to validate the effect of hyperthermia on exosome secretion. The effective targeting molecules and pathways changed by hyperthermia were explored by RNA microarray and verified in vitro. The adriamycin-resistant MCF-7/ADR cells co-incubated with the exosomes produced by MCF-7/ADR cells after hyperthermia were assessed. The uptake of exosomes by MCF-7/ADR cells after hyperthermia treatment was evaluated by confocal microscopy. Finally, the mechanism through which hyperthermia promotes exosome secretion by hyperthermia was determined.

RESULTS

Hyperthermia significantly suppressed the growth of adriamycin-resistant breast cancer cells and increased drug sensitivity by upregulating FOS and CREB5, genes related to longer overall survival in breast cancer patients. Moreover, hyperthermia promoted exosome secretion through Rab7b, a small GTPase that controls endosome transport. The upregulated FOS and CREB5 antioncogenes can be transferred to MCF-7/ADR cells by hyperthermia-treated MCF-7/ADR cell-secreted exosomes.

CONCLUSIONS

Our results demonstrated a novel function of hyperthermia in promoting exosome secretion in adriamycin-resistant breast cancer cells and revealed the effects of hyperthermia on tumor cell biology. These hyperthermia-triggered exosomes can carry antitumor genes to the residual tumor and tumor microenvironment, which may be more beneficial to the effects of hyperthermia. These results represent an exploration of the relationship between therapeutic strategies and exosome biology.