Human Mesenchymal Stem Cells Overexpressing Interleukin 2 Can Suppress Proliferation of Neuroblastoma Cells in Co-Culture and Activate Mononuclear Cells In Vitro

The crosstalk between primary MSCs and cancer cells in 2D and 3D cultures: potential therapeutic strategies and impact on drug resistance

The tumor microenvironment (TME) significantly influences cancer progression, and mesenchymal stem cells (MSCs) play a crucial role in interacting with tumor cells via paracrine signaling, affecting behaviors such as proliferation, migration, and epithelial-mesenchymal transition. While conventional 2D culture models have provided valuable insights, they cannot fully replicate the complexity and diversity of the TME. Therefore, developing 3D culture systems that better mimic in vivo conditions is essential. This review delves into the heterogeneous nature of the TME, spotlighting MSC-tumor cellular signaling and advancements in 3D culture technologies. Utilizing MSCs in cancer therapy presents opportunities to enhance treatment effectiveness and overcome resistance mechanisms. Understanding MSC interactions within the TME and leveraging 3D culture models can advance novel cancer therapies and improve clinical outcomes. Additionally, this review underscores the therapeutic potential of engineered MSCs, emphasizing their role in targeted anti-cancer treatments.

Advancements and Challenges in Personalized Therapy for BRAF-Mutant Melanoma: A Comprehensive Review

Over the past several decades, advancements in the treatment of BRAF-mutant melanoma have led to the development of BRAF inhibitors, BRAF/MEK inhibitor combinations, anti-PD-1 therapy, and anti-CTLA4 therapy. Although these therapies have shown substantial efficacy in clinical trials, their sustained effectiveness is often challenged by the tumor microenvironment, which is a highly heterogeneous and complex milieu of immunosuppressive cells that affect tumor progression. The era of personalized medicine holds substantial promise for the tailoring of treatments to individual genetic profiles. However, tumor heterogeneity and immune evasion mechanisms contribute to the resistance to immunotherapy. Despite these challenges, tumor-infiltrating lymphocyte (TIL) therapy, as exemplified by lifileucel, has demonstrated notable efficacy against BRAF V600-mutant melanoma. Additionally, early response biomarkers, such as COX-2 and MMP2, along with FDG-PET imaging, offer the potential to improve personalized immunotherapy by predicting patient responses and determining the optimal treatment duration. Future efforts should focus on reducing the T-cell harvesting periods and costs associated with TIL therapy to enhance efficiency and accessibility.

Nanotechnology and bioengineering approaches to improve the potency of mesenchymal stem cell as an off-the-shelf versatile tumor delivery vehicle

Targeting actionable mutations in oncogene-driven cancers and the evolution of immuno-oncology are the two prominent revolutions that have influenced cancer treatment paradigms and caused the emergence of precision oncology. However, intertumoral and intratumoral heterogeneity are the main challenges in both fields of precision cancer treatment. In other words, finding a universal marker or pathway in patients suffering from a particular type of cancer is challenging. Therefore, targeting a single hallmark or pathway with a single targeted therapeutic will not be efficient for fighting against tumor heterogeneity. Mesenchymal stem cells (MSCs) possess favorable characteristics for cellular therapy, including their hypoimmune nature, inherent tumor-tropism property, straightforward isolation, and multilineage differentiation potential. MSCs can be loaded with various chemotherapeutics and oncolytic viruses. The combination of these intrinsic features with the possibility of genetic manipulation makes them a versatile tumor delivery vehicle that can be used for in vivo selective tumor delivery of various chemotherapeutic and biological therapeutics. MSCs can be used as biofactory for the local production of chemical or biological anticancer agents at the tumor site. MSC-mediated immunotherapy could facilitate the sustained release of immunotherapeutic agents specifically at the tumor site, and allow for the achievement of therapeutic concentrations without the need for repetitive systemic administration of high therapeutic doses. Despite the enthusiasm evoked by preclinical studies that used MSC in various cancer therapy approaches, the translation of MSCs into clinical applications has faced serious challenges. This manuscript, with a critical viewpoint, reviewed the preclinical and clinical studies that have evaluated MSCs as a selective tumor delivery tool in various cancer therapy approaches, including gene therapy, immunotherapy, and chemotherapy. Then, the novel nanotechnology and bioengineering approaches that can improve the potency of MSC for tumor targeting and overcoming challenges related to their low localization at the tumor sites are discussed.

Cytokines secreted from bone marrow-derived mesenchymal stem cells promote apoptosis of CD34+ leukemic stem cells as anti-cancer therapy

Objective

The effect of mesenchymal stem cells (MSCs) on the immortal characteristics of malignant cells, particularly hematologic cancer cells, remains a topic of debate, with the underlying mechanisms still requiring further elucidation. We explored the in vitro effect of the bone marrow-derived MSCs (BM-MSCs) on CD34+ leukemic stem cells (LSCs) enriched from the KG1-a cell line by assessing apoptosis, measuring cytokine levels, and examining TERT protein expression. Additionally, the potential signaling pathways implicated in this process, such as P53, PTEN, NF-κB, ERK1/2, Raf-1, and H-RAS, were also investigated.

Methods

CD34+ LSCs were enriched from the KG1-a cell line with the magnetic activated cell sorting (MACS) method. Two cell populations (BM-MSCs and CD34+ LSCs) were co-cultured on trans well plates for seven days. Next, CD34+ LSCs were collected and subjected to Annexin V/PI assay, cytokine measurement, and western blotting.

Results

BM-MSCs caused a significant increase in early and late apoptosis in the CD34+LSCs. The significant presence of interleukin (IL)-2 and IL-4 was evident in the co-cultured media. In addition, BM-MSCs significantly increased the protein expression of P53, PTEN, NF-κB, and significantly decreased p-ERK1/2, Raf-1, H-RAS, and TERT.

Conclusion

The mentioned effects of IL-2 and IL-4 cytokines released from BM-MSCs on CD34+ LSCs as therapeutic agents were applied by the components of P53, PTEN, NF-κB, p-ERK1/2, Raf-1, and H-RAS signaling pathways.

The therapeutic effect of MSCs and their extracellular vesicles on neuroblastoma

Neuroblastoma is a common inflammatory-related cancer during infancy. Standard treatment modalities including surgical interventions, high-dose chemotherapy, radiotherapy, and immunotherapy are not able to increase survival rate and reduce tumor relapse in high-risk patients. Mesenchymal stem cells (MSCs) are known for their tumor-targeting and immunomodulating properties. MSCs could be engineered to express anticancer agents (i.e., growth factors, cytokines, pro-apoptotic agents) or deliver oncolytic viruses in the tumor microenvironment. As many functions of MSCs are mediated through their secretome, researchers have tried to use extracellular vesicles (EVs) from MSCs for targeted therapy of neuroblastoma. Here, we reviewed the studies to figure out whether the use of MSCs could be worthwhile in neuroblastoma therapy or not. Native MSCs have shown a promoting or inhibiting role in cancers including neuroblastoma. Therefore, MSCs are proposed as a vehicle to deliver anticancer agents such as oncolytic viruses to the neuroblastoma tumor microenvironment. Although modified MSCs or their EVs have been shown to suppress the tumorigenesis of neuroblastoma, further pre-clinical and clinical studies are required to come to a conclusion.

Increasing β-hexosaminidase A activity using genetically modified mesenchymal stem cells

GM2 gangliosidoses are a group of autosomal-recessive lysosomal storage disorders. These diseases result from a deficiency of lysosomal enzyme β-hexosaminidase A (HexA), which is responsible for GM2 ganglioside degradation. HexA deficiency causes the accumulation of GM2-gangliosides mainly in the nervous system cells, leading to severe progressive neurodegeneration and neuroinflammation. To date, there is no treatment for these diseases. Cell-mediated gene therapy is considered a promising treatment for GM2 gangliosidoses. This study aimed to evaluate the ability of genetically modified mesenchymal stem cells (MSCs-HEXA-HEXB) to restore HexA deficiency in Tay-Sachs disease patient cells, as well as to analyze the functionality and biodistribution of MSCs in vivo. The effectiveness of HexA deficiency cross-correction was shown in mutant MSCs upon interaction with MSCs-HEXA-HEXB. The results also showed that the MSCs-HEXA-HEXB express the functionally active HexA enzyme, detectable in vivo, and intravenous injection of the cells does not cause an immune response in animals. These data suggest that genetically modified mesenchymal stem cells have the potentials to treat GM2 gangliosidoses.

Engineered stem cell-based strategy: A new paradigm of next-generation stem cell product in regenerative medicine

Stem cells have garnered significant attention in regenerative medicine owing to their abilities of multi-directional differentiation and self-renewal. Despite these encouraging results, the market for stem cell products yields limited, which is largely due to the challenges faced to the safety and viability of stem cells in vivo. Besides, the fate of cells re-infusion into the body unknown is also a major obstacle to stem cell therapy. Actually, both the functional protection and the fate tracking of stem cells are essential in tissue homeostasis, repair, and regeneration. Recent studies have utilized cell engineering techniques to modify stem cells for enhancing their treatment efficiency or imparting them with novel biological capabilities, in which advances demonstrate the immense potential of engineered cell therapy. In this review, we proposed that the "engineered stem cells" are expected to represent the next generation of stem cell therapies and reviewed recent progress in this area. We also discussed potential applications of engineered stem cells and highlighted the most common challenges that must be addressed. Overall, this review has important guiding significance for the future design of new paradigms of stem cell products to improve their therapeutic efficacy.

Adipose-Derived Mesenchymal Stem Cell (MSC) Immortalization by Modulation of hTERT and TP53 Expression Levels

Mesenchymal stem cells (MSCs) are pivotal players in tissue repair and hold great promise as cell therapeutic agents for regenerative medicine. Additionally, they play a significant role in the development of various human diseases. Studies on MSC biology have encountered a limiting property of these cells, which includes a low number of passages and a decrease in differentiation potential during in vitro culture. Although common methods of immortalization through gene manipulations of cells are well established, the resulting MSCs vary in differentiation potential compared to primary cells and eventually undergo senescence. This study aimed to immortalize primary adipose-derived MSCs by overexpressing human telomerase reverse transcriptase (hTERT) gene combined with a knockdown of TP53. The research demonstrated that immortalized MSCs maintained a stable level of differentiation into osteogenic and chondrogenic lineages during 30 passages, while also exhibiting an increase in cell proliferation rate and differentiation potential towards the adipogenic lineage. Long-term culture of immortalized cells did not alter cell morphology and self-renewal potential. Consequently, a genetically stable line of immortalized adipose-derived MSCs (iMSCs) was established.

Substrate topographies modulate the secretory activity of human bone marrow mesenchymal stem cells

BACKGROUND

Mesenchymal stem cells (MSCs) secrete a diversity of factors with broad therapeutic potential, yet current culture methods limit potency outcomes. In this study, we used topographical cues on polystyrene films to investigate their impact on the secretory profile and potency of bone marrow-derived MSCs (hBM-MSCs). hBM-MSCs from four donors were cultured on topographic substrates depicting defined roughness, curvature, grooves and various levels of wettability.

METHODS

The topographical PS-based array was developed using razor printing, polishing and plasma treatment methods. hBM-MSCs from four donors were purchased from RoosterBio and used in co-culture with peripheral blood mononuclear cells (PBMCs) from Cell Applications Inc. in an immunopotency assay to measure immunosuppressive capacity. Cells were cultured on low serum (2%) for 24-48 h prior to analysis. Image-based analysis was used for cell quantification and morphology assessment. Metabolic activity of BM-hMSCs was measured as the mitochondrial oxygen consumption rate using an extracellular flux analyzer. Conditioned media samples of BM-hMSCs were used to quantify secreted factors, and the data were analyzed using R statistics. Enriched bioprocesses were identify using the Gene Ontology tool enrichGO from the clusterprofiler. One-way and two-way ANOVAs were carried out to identify significant changes between the conditions. Results were deemed statistically significant for combined P < 0.05 for at least three independent experiments.

RESULTS

Cell viability was not significantly affected in the topographical substrates, and cell elongation was enhanced at least twofold in microgrooves and surfaces with a low contact angle. Increased cell elongation correlated with a metabolic shift from oxidative phosphorylation to a glycolytic state which is indicative of a high-energy state. Differential protein expression and gene ontology analyses identified bioprocesses enriched across donors associated with immune modulation and tissue regeneration. The growth of peripheral blood mononuclear cells (PBMCs) was suppressed in hBM-MSCs co-cultures, confirming enhanced immunosuppressive potency. YAP/TAZ levels were found to be reduced on these topographies confirming a mechanosensing effect on cells and suggesting a potential role in the immunomodulatory function of hMSCs.

CONCLUSIONS

This work demonstrates the potential of topographical cues as a culture strategy to improve the secretory capacity and enrich for an immunomodulatory phenotype in hBM-MSCs.

Cytokine sustained delivery for cancer therapy; special focus on stem cell- and biomaterial- based delivery methods

As immune regulators, cytokines serve critical role as signaling molecules in response to danger, tissue damage, or injury. Importantly, due to their vital role in immunological surveillance, cytokine therapy has become a promising therapeutics for cancer therapy. Cytokines have, however, been used only in certain clinical settings. Two key characteristics of cytokines contribute to this clinical translational challenge: first, they are highly pleiotropic, and second, in healthy physiology, they are typically secreted and act very locally in tissues. Systemic administration of the cytokines can consequently result in serious side effects. Thus, scientists have sought various strategies to circumvent theses hurdles. Recent in vivo reports signify that cytokine delivery platforms can increase their safety and therapeutic efficacy in tumor xenografts. Meanwhile, cytokine delivery using multipotent stem cells, in particular mesenchymal stem/stromal cells (MSCs), and also a diversity of particles and biomaterials has demonstrated greater capability in this regards. Herein, we take a glimpse into the recent advances in cytokine sustained delivery using stem cells and also biomaterials to ease safe and effective treatments of a myriad of human tumors.

Interleukin gene delivery for cancer gene therapy: In vitro and in vivo studies

Cytokine-mediated cancer therapy has the potential to enhance immunotherapeutic approaches and cancer elimination plans through the endowing of the immune system by providing improved anticancer immunity. Despite the encouraging pioneer studies on interleukins (ILs), the influence of ILs-originated therapeutics is still restricted by a class of potent immunoregulatory cytokines, systemic dose-limiting toxicities, ILs pleiotropy, and administration issues. During previous years, the area of transferring genes encoding immunostimulatory ILs was fundamentally widened to overcome these challenges and expedite ILs-based tumor regression. Numerous viral and non-viral delivery systems are currently available to act as crucial elements of the gene therapy toolbox. Moreover, cell-based cancer therapies are recruiting MSCs in the role of versatile gene delivery platforms to design one of the promising therapeutic approaches. These formulated gene carrier systems can provide possible alternatives to diminish dose-limiting adverse effects, promote administration, and enhance the therapeutic activity of ILs-derived treatment modalities in cancer treatment. This review provides a discussion on the advances of ILs gene delivery systems while focusing on the developing platforms in preclinical cancer immunogene therapy studies.

Cytochalasin B-Induced Membrane Vesicles from TRAIL-Overexpressing Mesenchymal Stem Cells Induce Extrinsic Pathway of Apoptosis in Breast Cancer Mouse Model

Tumor-necrosis-factor-associated apoptosis-inducing ligand (TRAIL) is one of the most promising therapeutic cytokines that selectively induce apoptosis in tumor cells. It is known that membrane vesicles (MVs) can carry the surface markers of parental cells. Therefore, MVs are of interest as a tool for cell-free cancer therapy. In this study, membrane vesicles were isolated from TRAIL-overexpressing mesenchymal stem cells using cytochalasin B treatment (CIMVs). To evaluate the antitumor effect of CIMVs-TRAIL in vivo, a breast cancer mouse model was produced. The animals were intratumorally injected with 50 µg of native CIMVs or CIMVs-TRAIL for 12 days with an interval of two days. Then, tumor growth rate, tumor necrotic area, the expression of the apoptosis-related genes CASP8, BCL-2, and BAX and the level of CASP8 protein were analyzed. A 1.8-fold increase in the CAS8 gene mRNA and a 1.7-fold increase in the CASP8 protein level were observed in the tumors injected with CIMVs-TRAIL. The expression of the anti-apoptotic BCL-2 gene in the CIMV-TRAIL group remained unchanged, while the mRNA level of the pro-apoptotic BAX gene was increased by 1.4 times, which indicated apoptosis activation in the tumor tissue. Thus, CIMVs-TRAIL were able to activate the extrinsic apoptosis pathway and induce tumor cell death in the breast cancer mouse model.

MSCs can be a double-edged sword in tumorigenesis

Mesenchymal stem cells (MSCs) have been used to treat various diseases including Alzheimer's disease and cancer. In particular, the immunomodulatory function of MSCs plays a major role in cancer therapy using stem cells. However, MSCs exert promotive and inhibitory effects on cancer. The immunomodulatory effects of MSCs in the tumor microenvironment (TME) are ambiguous, which is the primary reason for the different outcomes of MSCs therapies for tumors. This review discusses the use of MSCs in cancer immunotherapy and their immunomodulatory mechanisms in cancers.

Characteristics and Resistance to Cisplatin of Human Neuroblastoma Cells Co-Cultivated with Immune and Stromal Cells

We investigated the features of the morphology and cytokine profiles of neuroblastoma SH-SY5Y cells, bone marrow-derived mesenchymal stromal/stem cells (BM-MSCs), and peripheral blood mononuclear cells (PBMCs) in double (BM-MSCs + SH-SY5Y cells) and triple (BM-MSCs + SH-SY5Y cells + PBMCs) co-cultures incubated on plastic and Matrigel. Cells in the co-cultures communicated by vesicular transport and by exchanging membrane and cytoplasmic components. The cytokine profile of double and triple co-cultures incubated on Matrigel and plastic had differences and showed the highest concentration of a number of chemokines/cytokines, such as CXCL8/IL-8, I-TAC/CXCL11, IP10/CXCL10, MDC/CCL22, MIP-1α/CCL3, IL-1β, ENA-78/CXCL5, Gro-α/CXCL1, MCP-1/CCL2, TERC/CCL25, CXCL8/IL-8, and IL-6. High concentrations of inflammatory chemokines/cytokines in the conditioned medium of triple co-culture form a chronic inflammation, which brings the presented co-cultivation system closer to a natural tumor. Triple co-cultures were more resistant to cisplatin (CDDP) than the double- and monoculture of SH-SY5Y. The mRNA levels of BCL2, BCL2L1, RAC1, CAV1, CASP3, and BAX genes were changed in cells after co-culturing and CDDP treatment in double and triple co-cultures. The expression of the BCL2, BAX, CAV1, and CASP3 proteins in SH-SY5Y cells after the triple co-culture and CAV1 and BAX protein expression in SH-SY5Y cells after the double co-culture were determined. This study demonstrated the nature of the cellular interactions between components of tumor niche and the intercellular influence on chemoresistance observed in our tumor model, which should enable the development of novel test systems for anti-tumor agents.

Comparative Analysis of Natural and Cytochalasin B-Induced Membrane Vesicles from Tumor Cells and Mesenchymal Stem Cells

To date, there are numerous protocols for the isolation of extracellular vesicles (EVs). Depending on the isolation method, it is possible to obtain vesicles with different characteristics, enriched with specific groups of proteins, DNA and RNA, which affect similar types of cells in the opposite way. Therefore, it is important to study and compare methods of vesicle isolation. Moreover, the differences between the EVs derived from tumor and mesenchymal stem cells are still poorly understood. This article compares EVs from human glioblastoma cells and mesenchymal stem cells (MSCs) obtained by two different methods, ultracentrifugation and cytochalasin B-mediated induction. The size of the vesicles, the presence of the main EV markers, the presence of nuclear and mitochondrial components, and the molecular composition of the vesicles were determined. It has been shown that EVs obtained by both ultracentrifugation and cytochalasin B treatment have similar features, contain particles of endogenous and membrane origin and can interact with monolayer cultures of tumor cells.

Cell-based drug delivery systems and their in vivo fate

Cell-based drug delivery systems (DDSs) have received attention recently because of their unique biological properties and self-powered functions, such as excellent biocompatibility, low immunogenicity, long circulation time, tissue-homingcharacteristics, and ability to cross biological barriers. A variety of cells, including erythrocytes, stem cells, and lymphocytes, have been explored as functional vectors for the loading and delivery of various therapeutic payloads (e.g., small-molecule and nucleic acid drugs) for subsequent disease treatment. These cell-based DDSs have their own unique in vivo fates, which are attributed to various factors, including their biological properties and functions, the loaded drugs and loading process, physiological and pathological circumstances, and the body's response to these carrier cells, which result in differences in drug delivery efficiency and therapeutic effect. In this review, we summarize the main cell-based DDSs and their biological properties and functions, applications in drug delivery and disease treatment, and in vivo fate and influencing factors. We envision that the unique biological properties, combined with continuing research, will enable development of cell-based DDSs as friendly drug vectors for the safe, effective, and even personalized treatment of diseases.

Mesenchymal stem cells: A living carrier for active tumor-targeted delivery

The strategy of using mesenchymal stem cells (MSCs) as a living carrier for active delivery of therapeutic agents targeting tumor sites has been attempted in a wide range of studies to validate the feasibility and efficacy for tumor treatment. This approach reveals powerful tumor targeting and tumor penetration. In addition, MSCs have been confirmed to actively participate in immunomodulation of the tumor microenvironment. Thus, MSCs are not inert delivery vehicles but have a strong impact on the fate of tumor cells. In this review, these active properties of MSCs are addressed to highlight the advantages and challenges of using MSCs for tumor-targeted delivery. In addition, some of the latest examples of using MSCs to carry a variety of anti-tumor agents for tumor-targeted therapy are summarized. Recent technologies to improve the performance and safety of this delivery strategy will be introduced. The advances, applications, and challenges summarized in this review will provide a general understanding of this promising strategy for actively delivering drugs to tumor tissues.

The Dual Role of Mesenchymal Stromal Cells and Their Extracellular Vesicles in Carcinogenesis

Simple Summary

Extracellular vesicles (EVs) are membrane structures that play the role of intermediaries between tumor cells and the tumor microenvironment (TME) because they have the ability to transport lipids, transcription factors, mRNA, and proteins. Mesenchymal stem cells (MSCs) are a major component of the TME and may have different effects on tumor progression using EVs. This review includes information about various studies which have reported that EVs from MSCs can have either antitumor or pro-tumor effects, depending on both the tumor type and developmental stage. It provides an overview of the published data on EV MSCs and their effect on tumor cells. In addition, the use of EV MSCs for the development of new methods for treating oncological diseases is described.

Abstract

Mesenchymal stem cells (MSCs) are a major component of the tumor microenvironment (TME) and play an important role in tumor progression. MSCs remodel the extracellular matrix, participate in the epithelial–mesenchymal transition, promote the spread of metastases, and inhibit antitumor immune responses in the TME; however, there are also data pertaining to the antitumor effects of MSCs. MSCs activate the cell death mechanism by modulating the expression of proteins involved in the regulation of the cell cycle, angiogenesis receptors, and proapoptotic proteins. One of the main ways in which MSCs and TME interact is through the production of extracellular vesicles (EVs) by cells. Currently, data on the effects of both MSCs and their EVs on tumor cells are rather contradictory. Various studies have reported that EVs from MSCs can have either antitumor or pro-tumor effects, depending on both the tumor type and developmental stage. In this review, we discuss published data on EV MSCs and their effect on tumor cells. The molecular composition of vesicles obtained from MSCs is also presented in the review. In addition, the use of EV MSCs for the development of new methods for treating oncological diseases is described.

Analysis of the Interaction of Human Neuroblastoma Cell-Derived Cytochalasin B Induced Membrane Vesicles with Mesenchymal Stem Cells Using Imaging Flow Cytometry

At present, there is an increasing interest in the potential role of extracellular vesicles (EVs), acting as multi-signal messengers of the tumor stroma, in the development and progression of tumor. Tumor cell-derived EVs are considered a potential vector for the targeted delivery of antitumor agents due to the ability to fuse with parental cells through endocytosis and release their contents into the cytoplasm of the recipient cell. Tumor cell-derived EVs could be also used for priming immune cells and therapeutic vaccine development. It is also known that mesenchymal stem cells (MSCs) have a tropism toward tumor niches. It is believed that MSC migration to the tumor is due to its inflammatory signaling. Presumably, with the accumulation of MSCs at tumor sites, these cells differentiate into pericytes or tumor-associated fibroblasts, thereby forming a supporting tumor growth microenvironment. However, besides the ability to promote tumor progression, MSCs can also suppress its growth by inhibiting proliferation and cell cycle progression, and angiogenesis. Thus, the further studies of the MSC role in TME and MSC interaction with other cells of the tumor stroma, including through EVs, are of particular interest. To increase the yield of vesicles the isolation method based on pharmacological disorganization of the actin cytoskeleton induced by treating with cytochalasin B was used in this study. In this investigation the interaction of SH-SY5Y neuroblastoma cell-derived membrane vesicles, obtained using cytochalasin B (CIMVs), with human bone marrow-derived MSCs was analyzed using imaging flow cytometry. Using transmission electron microscopy, it was shown that CIMVs have a size similar to that of natural microvesicles, which is 100–1000 nm. Using imaging flow cytometry, it was shown that after 24 h of co-cultivation 6% of the MSCs contained a large number of CIMVs, and 42% of the MSCs contained a small amount of CIMVs. Cultivation of MSCs with SH-SY5Y cell-derived CIMVs also induced dose-dependent decrease in the expression of CD markers typical for MSCs. Thus, the internalization of SH-SY5Y cell-derived CIMVs within MSCs and the ability of the CIMVs to modulate immunophenotype of the recipient cells were shown. However, further studies are required to determine the effect of CIMVs on pro- or antioncogenic phenotype and function of MSCs.

Mesenchymal Stem/Stromal Cells as a Vehicle for Cytokine Delivery: An Emerging Approach for Tumor Immunotherapy

Pro-inflammatory cytokines can effectively be used for tumor immunotherapy, affecting every step of the tumor immunity cycle. Thereby, they can restore antigen priming, improve the effector immune cell frequencies in the tumor microenvironment (TME), and eventually strengthen their cytolytic function. A renewed interest in the anticancer competencies of cytokines has resulted in a substantial promotion in the number of trials to address the safety and efficacy of cytokine-based therapeutic options. However, low response rate along with the high toxicity associated with high-dose cytokine for reaching desired therapeutic outcomes negatively affect their clinical utility. Recently, mesenchymal stem/stromal cells (MSCs) due to their pronounced tropism to tumors and also lower immunogenicity have become a promising vehicle for cytokine delivery for human malignancies. MSC-based delivery of the cytokine can lead to the more effective immune cell-induced antitumor response and provide sustained release of target cytokines, as widely evidenced in a myriad of xenograft models. In the current review, we offer a summary of the novel trends in cytokine immunotherapy using MSCs as a potent and encouraging carrier for antitumor cytokines, focusing on the last two decades' animal reports.

Mesenchymal Stem/Stromal Cell-Based Delivery: A Rapidly Evolving Strategy for Cancer Therapy

Mesenchymal stem/stromal cell (MSC)-based therapy has become an attractive and advanced scientific research area in the context of cancer therapy. This interest is closely linked to the MSC-marked tropism for tumors, suggesting them as a rational and effective vehicle for drug delivery for both hematological and solid malignancies. Nonetheless, the therapeutic application of the MSCs in human tumors is still controversial because of the induction of several signaling pathways largely contributing to tumor progression and metastasis. In spite of some evidence supporting that MSCs may sustain cancer pathogenesis, increasing proofs have indicated the suppressive influences of MSCs on tumor cells. During the last years, a myriad of preclinical and some clinical studies have been carried out or are ongoing to address the safety and efficacy of the MSC-based delivery of therapeutic agents in diverse types of malignancies. A large number of studies have focused on the MSC application as delivery vehicles for tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), chemotherapeutic drug such as gemcitabine (GCB), paclitaxel (PTX), and doxorubicin (DOX), prodrugs such as 5-fluorocytosine (5-FC) and ganciclovir (GCV), and immune cell-activating cytokines along with oncolytic virus. In the current review, we evaluate the latest findings rendering the potential of MSCs to be employed as potent gene/drug delivery vehicle for inducing tumor regression with a special focus on the in vivo reports performed during the last two decades.

Genetically-Modified Stem Cell in Regenerative Medicine and Cancer Therapy; A New Era

Recently, genetic engineering by various strategies to stimulate gene expression in a specific and controllable mode is a speedily growing therapeutic approach. Genetic modification of human stem or progenitor cells, such as embryonic stem cells (ESCs), neural progenitor cells (NPCs), mesenchymal stem/stromal cells (MSCs), and hematopoietic stem cells (HSCs) for direct delivery of specific therapeutic molecules or genes has been evidenced as an opportune plan in the context of regenerative medicine due to their supported viability, proliferative features, and metabolic qualities. On the other hand, a large number of studies have investigated the efficacy of modified stem cells in cancer therapy using cells from various sources, disparate transfection means for gene delivery, different transfected yields, and wide variability of tumor models. Accordingly, cell-based gene therapy holds substantial aptitude for the treatment of human malignancy as it could relieve signs or even cure cancer succeeding expression of therapeutic or suicide transgene products; however, there exist inconsistent results in this regard. Herein, we deliver a brief overview of stem cell potential to use in cancer therapy and regenerative medicine and importantly discuss stem cells based gene delivery competencies to stimulate tissue repair and replacement in concomitant with their potential to use as an anti-cancer therapeutic strategy, focusing on the last two decades in vivo studies.

The Potential of Mesenchymal Stromal Cells in Neuroblastoma Therapy for Delivery of Anti-Cancer Agents and Hematopoietic Recovery

Neuroblastoma is one of the most common pediatric cancers and a major cause of cancer-related death in infancy. Conventional therapies including high-dose chemotherapy, stem cell transplantation, and immunotherapy approach a limit in the treatment of high-risk neuroblastoma and prevention of relapse. In the last two decades, research unraveled a potential use of mesenchymal stromal cells in tumor therapy, as tumor-selective delivery vehicles for therapeutic compounds and oncolytic viruses and by means of supporting hematopoietic stem cell transplantation. Based on pre-clinical and clinical advances in neuroblastoma and other malignancies, we assess both the strong potential and the associated risks of using mesenchymal stromal cells in the therapy for neuroblastoma. Furthermore, we examine feasibility and safety aspects and discuss future directions for harnessing the advantageous properties of mesenchymal stromal cells for the advancement of therapy success.

Cytochalasin B-Induced Membrane Vesicles from Human Mesenchymal Stem Cells Overexpressing IL2 Are Able to Stimulate CD8+ T-Killers to Kill Human Triple Negative Breast Cancer Cells

Simple Summary

Almost all human cells release extracellular vesicles participating in intercellular communication. Extracellular vesicles are rounded structures surrounded by the cytoplasmic membrane, which embody cytoplasmic contents of the parental cells, which makes extracellular vesicles a promising therapeutic tool for cell-free cancer therapy. In this study, human mesenchymal stem cells were genetically modified to overexpress human interleukin-2 (IL2), a cytokine which regulates the proliferation and activation of immune cells. Membrane vesicle release from native and genetically modified stem cells was induced by cytochalasin B treatment to increase the yield of membrane vesicles. To evaluate the immunomodulating properties of isolated membrane vesicles, immune cells were isolated from human peripheral blood and co-cultured with membrane vesicles from native or IL2 overexpressing stem cells. To analyze the anti-tumor activity of immune cells after interaction with IL2-enriched membrane vesicles, immune cells were co-cultured with triple negative breast cancer cells. As a result, IL2-enriched membrane vesicles were able to activate and stimulate the proliferation of immune cells, which in turn were able to induce apoptosis in breast cancer cells. Therefore, the production of IL2-enriched membrane vesicles represents a unique opportunity to meet the potential of extracellular vesicles to be used in clinical applications for cancer therapy.

Abstract

Interleukin 2 (IL2) was one of the first cytokines used for cancer treatment due to its ability to stimulate anti-cancer immunity. However, recombinant IL2-based therapy is associated with high systemic toxicity and activation of regulatory T-cells, which are associated with the pro-tumor immune response. One of the current trends for the delivery of anticancer agents is the use of extracellular vesicles (EVs), which can carry and transfer biologically active cargos into cells. The use of EVs can increase the efficacy of IL2-based anti-tumor therapy whilst reducing systemic toxicity. In this study, human adipose tissue-derived mesenchymal stem cells (hADSCs) were transduced with lentivirus encoding IL2 (hADSCs-IL2). Membrane vesicles were isolated from hADSCs-IL2 using cytochalasin B (CIMVs-IL2). The effect of hADSCs-IL2 and CIMVs-IL2 on the activation and proliferation of human peripheral blood mononuclear cells (PBMCs) as well as the cytotoxicity of activated PBMCs against human triple negative cancer MDA-MB-231 and MDA-MB-436 cells were evaluated. The effect of CIMVs-IL2 on murine PBMCs was also evaluated in vivo. CIMVs-IL2 failed to suppress the proliferation of human PBMCs as opposed to hADSCs-IL2. However, CIMVs-IL2 were able to activate human CD8⁺ T-killers, which in turn, killed MDA-MB-231 cells more effectively than hADSCs-IL2-activated CD8⁺ T-killers. This immunomodulating effect of CIMVs-IL2 appears specific to human CD8⁺ T-killer cells, as the same effect was not observed on murine CD8⁺ T-cells. In conclusion, the use of CIMVs-IL2 has the potential to provide a more effective anti-cancer therapy. This compelling evidence supports further studies to evaluate CIMVs-IL2 effectiveness, using cancer mouse models with a reconstituted human immune system.

Current Trends in Cancer Immunotherapy

The search for an effective drug to treat oncological diseases, which have become the main scourge of mankind, has generated a lot of methods for studying this affliction. It has also become a serious challenge for scientists and clinicians who have needed to invent new ways of overcoming the problems encountered during treatments, and have also made important discoveries pertaining to fundamental issues relating to the emergence and development of malignant neoplasms. Understanding the basics of the human immune system interactions with tumor cells has enabled new cancer immunotherapy strategies. The initial successes observed in immunotherapy led to new methods of treating cancer and attracted the attention of the scientific and clinical communities due to the prospects of these methods. Nevertheless, there are still many problems that prevent immunotherapy from calling itself an effective drug in the fight against malignant neoplasms. This review examines the current state of affairs for each immunotherapy method, the effectiveness of the strategies under study, as well as possible ways to overcome the problems that have arisen and increase their therapeutic potentials.