The Dual Role of Mesenchymal Stem Cells in Cancer Pathophysiology: Pro-Tumorigenic Effects versus Therapeutic Potential

Mesenchymal stromal cells in bone marrow niche of patients with multiple myeloma: a double-edged sword

Multiple myeloma (MM) is a hematological malignancy defined by the abnormal proliferation and accumulation of plasma cells (PC) within the bone marrow (BM). While multiple myeloma impacts the bone, it is not classified as a primary bone cancer. The bone marrow microenvironment significantly influences the progression of myeloma and its treatment response. Mesenchymal stromal cells (MSCs) in this environment engage with myeloma cells and other bone marrow components via direct contact and the secretion of soluble factors. This review examines the established roles of MSCs in multiple facets of MM pathology, encompassing their pro-inflammatory functions, contributions to tumor epigenetics, effects on immune checkpoint inhibitors (ICIs), influence on reprogramming, chemotherapy resistance, and senescence. This review investigates the role of MSCs in the development and progression of MM.

Study on the efficacy of IFN-γ- and sPD-1-overexpressing BMSCs in enhancing immune effects for the treatment of lung adenocarcinoma

Background

Soluble programmed cell death receptor-1 (sPD-1) blocks the PD-1/PD-L1 pathway, reverses tumor immune suppression, and inhibits tumor growth. However, clinical applications are limited by its poor tissue distribution and rapid dispersion. Bone marrow-derived mesenchymal stem cells (BMSCs) are favorable carriers for tumor immunotherapy due to their capacity for external gene introduction and targeted tumor homing. However, they may inadvertently promote tumor growth. Interferon-gamma (IFN-γ) inhibits BMSC-mediated tumor growth and stimulates antigen-presenting cells to activate T lymphocytes. This study utilizes BMSCs transfected with IFN-γ as carriers for sPD-1, enabling the targeted homing of sPD-1 to tumor tissues, thereby enhancing the efficacy and sustained stability of immunotherapy.

Methods

stable IFN-γ- and sPD-1-overexpressing BMSCs were successfully constructed by lentiviral transfection. A non-contact co-culture system was established with Lewis and A549 lung adenocarcinoma cells to observe changes in the lung cancer cells after co-culture, using assays including cell migration and invasion experiments, as well as cellular senescence detection. Additionally, a subcutaneous lung adenocarcinoma model was established in C57BL/6J mice for intervention studies. Tumor volume, cellular apoptosis in tumor tissue (assessed by TUNEL assay), peripheral Treg cells (analyzed by flow cytometry), and histopathological markers (evaluated by HE staining and immunohistochemistry) were analyzed. The expression levels of BAX, BCL-2, AKT, PI3K, and PD-L1 were assessed by quantitative PCR and Western Blot.

Results

IFN-γ- and sPD-1-overexpressing BMSCs exhibited high bioactivity and genetic stability, inhibiting lung adenocarcinoma cell proliferation, accelerating cellular senescence, and reducing migration and invasion. Furthermore, they upregulate Bax expression, downregulate Bcl-2, and promote apoptosis. Additionally, these cells alleviate inflammatory damage in lung tissue of tumor-bearing mice, lower Treg cell levels to inhibit tumor immune evasion, and reduce the expression of PI3K/AKT and PD-L1.

Conclusion

IFN-γ- and sPD-1-overexpressing BMSCs effectively inhibit lung adenocarcinoma cell growth and tumor progression. The primary mechanisms include suppression of cancer cell growth, migration, and invasion; promotion of apoptosis and senescence in cancer cells; modulation of Treg cells; and inhibition of the PI3K/AKT signaling pathway and PD-1/PD-L1 pathways.

Impact of Minimally Manipulated Cell Therapy on Immune Responses in Radiation-Induced Skin Wound Healing

The current treatment of radiation-induced skin wounds utilizes mainly conventional therapies, including topical steroids, creams, ointments, and hydrogel dressings, which do not take into account the immunologic changes that occur in the skin after radiation exposure. Therefore, it is relevant to consider alternative therapies and their impact on changes in the immune landscape of the skin. The aim of this study was to investigate the effect of allogeneic minimally manipulated keratinocytes and fibroblasts on rat skin repair and the development of immune responses. We found that the use of cell therapy compared to treatment with syntazone ointment and no treatment resulted in faster healing and a reduction in the size of radiation-induced skin wounds, area of inflammation, and edema. Additionally, in the group receiving the cell therapy application, there was an observed increase in the number of mast cells (MCs), activation of MC interaction with M2 macrophages, a reduction in the direct contact of MCs with the vascular bed, an increase in the content of collagen fibers due to the intensification of collagen fibrillogenesis, and a restoration of their histotopographic organization. Thus, the positive effect of cell therapy based on allogeneic minimally manipulated keratinocytes and fibroblasts on skin regeneration indicated that it can be used in clinical practice to improve the effectiveness of rehabilitation after radiation therapy.

Mesenchymal stem cells modulate breast cancer progression through their secretome by downregulating ten-eleven translocation 1

Mesenchymal stem cells (MSCs) have emerged as crucial players within the tumor microenvironment (TME), contributing through their paracrine secretome. Depending on the context, the MSC-derived secretome can either support or inhibit tumor growth. This study investigates the role of MSC-derived secretome in modulating breast cancer (BC) cell behavior, with a focus on ten-eleven translocation 1 (TET1), a DNA demethylase with known oncogenic properties in triple-negative breast cancer (TNBC). We first isolated and characterized human bone marrow-derived MSCs, and then assessed the impact of their secretome on BC cells. Treatment with the MSC-derived secretome significantly inhibited the proliferation and migration of both MDA-MB-231 and MCF-7 BC cell lines, resulting in reduced cell viability and migration rates compared to control cells. Western blot analyses revealed downregulation of Cyclin D1 and c-Myc, along with decreased expression of N-cadherin and increased expression of E-cadherin, indicating potential inhibition of the epithelial-to-mesenchymal transition. Differential gene expression analyses highlighted TET1 as significantly upregulated in TNBC tissues compared to normal samples. Further experiments confirmed that the MSC-derived secretome downregulated TET1 expression in BC cells, as evidenced by RT-qPCR and western blot analyses. To explore TET1's functional role, we silenced TET1 with siRNAs, observing cell cycle arrest and enhanced apoptosis-effects that mirrored those seen with MSC-secretome treatment. Notably, TET1 knockdown also increased MDA-MB-231 cell sensitivity to cisplatin, suggesting a role for TET1 in chemoresistance. These findings provide insight into the ability of MSCs to modulate BC cell progression through their secretome, highlighting the involvement of TET1 downregulation in inhibiting BC cell progression and enhancing cisplatin chemosensitivity. The MSC-derived secretome thus holds promise as an innovative, cell-free therapeutic approach in BC treatment.

Fate and long-lasting therapeutic effects of mesenchymal stromal/stem-like cells: mechanistic insights

A large body of evidence suggests that mesenchymal stromal cells (MSCs) are able to respond rapidly to the cytokine milieu following systemic infusion. This encounter has the potential to dictate their therapeutic efficacy (also referred to as licensing). MSCs are able to rapidly react to cellular damage by migrating to the inflamed tissue and ultimately modifying the inflammatory microenvironment. However, the limited use of MSCs in clinical practice can be attributed to a lack of understanding of the fate of MSCs in patients after administration and long term MSC-derived therapeutic activity. While the known physiological effectors of viable MSCs make a relative contribution, an innate property of MSCs as a therapeutic agent is their caspase-dependent cell death. These mechanisms may be involving the functional reprogramming of myeloid phagocytes via efferocytosis, the process by which apoptotic bodies (ABs) are identified for engulfment by both specialized and non-specialized phagocytic cells. Recent studies have provided evidence that the uptake of ABs with a distinct genetic component can induce changes in gene expression through the process of epigenetic remodeling. This phenomenon, known as 'trained immunity', has a significant impact on immunometabolism processes. It is hypothesized that the diversity of recipient cells within the inflammatory stroma adjacent to MSCs may potentially serve as a biomarker for predicting the clinical outcome of MSC treatment, while also contributing to the variable outcomes observed with MSC-based therapies. Therefore, the long-term reconstructive process of MSCs may potentially be mediated by MSC apoptosis and subsequent phagocyte-mediated efferocytosis.

Targeting the tumor microenvironment with mesenchymal stem cells based delivery approach for efficient delivery of anticancer agents: An updated review

Drug delivery to cancer cells continues to present a major therapeutic challenge. Mesenchymal stem cells (MSCs) possess an intrinsic ability to migrate specifically to tumor tissues, making them promising candidates for targeted drug delivery. Evidence from preclinical studies indicates that MSCs loaded with therapeutic anti-cancer agents exhibit considerable anti-tumor activity. Moreover, several clinical trials are currently evaluating their effectiveness in cancer patients. The integration of MSCs with synthetic nanoparticles (NPs) enhances their therapeutic potential, particularly through the use of cell membrane-coated NPs, which represent a significant advancement in the field. This review systematically investigates the tumor microenvironment, the sources of MSCs, the tumor homing mechanisms, and the methods of loading and releasing anticancer drugs from MSCs. Furthermore, cutting-edge strategies to improve the efficacy of MSCs based drug delivery systems (DDS) including the innovative use of MSC membrane coated nanoparticles have been discussed. The study concludes with an overview of the therapeutic use of MSCs as drug carriers, including a detailed analysis of the mechanisms by which MSCs deliver therapeutics to cancer cells, enabling targeted drug delivery. It aims to elucidate the current state of this approach, identify key areas for development, and outline potential future directions for advancing MSCs based cancer therapies.

A review of the immunomodulatory properties of mesenchymal stem cells and their derived extracellular vesicles in small-cell and non-small-cell lung cancer cells

Among the most challenging diseases to treat is lung cancer (LC). While immunotherapy has a checkered history, it has lately shown great promise in the treatment of LC, and interest in this promising new approach is on the rise around the globe. Immunotherapy using mesenchymal stem cells (MSCs) is gaining popularity. Regenerative medicine, cell therapy, and immune modulation are three areas that have shown significant interest in MSCs. More than that, MSCs have recently attracted attention as potential anti-cancer drug delivery vehicles due to their inherent ability to go home to tumor locations. Making MSCs a double-edged sword in the fight against neoplastic illnesses, they are also known to impart pro-oncogenic properties. Additionally, multiple studies have proposed extracellular vesicles (EVs) secreted by MSCs as a potential therapeutic agent or method for delivering anti-cancer drugs. However, there has been conflicting evidence regarding the impact of MSCs or MSC-EV on the behavior of cancer cells, and the exact mechanism for this effect is still unknown. Our research has focused on MSCs and their key characteristics, such as their immunomodulatory capabilities for cancer therapy. Our research has also explored the potential of MSCs and their derivatives to treat small-cell and non-small-cell lung cancers (NSCLC and SCLC, respectively) by leveraging MSCs' immunomodulatory characteristics. At the end of this article, we covered the pros and cons of this therapy procedure, as well as what researchers want to do in the future to make it more suitable for clinical application in LC treatment.

Mesenchymal stem cell-mediated adipogenic transformation: a key driver of oral squamous cell carcinoma progression

BACKGROUND

Interaction between mesenchymal stem cells (MSCs) and oral squamous cell carcinoma (OSCC) cells plays a major role in OSCC progression. However, little is known about adipogenic differentiation alteration in OSCC-derived MSCs (OSCC-MSCs) and how these alterations affect OSCC growth.

METHODS

MSCs were successfully isolated and cultured from normal gingival tissue, OSCC peritumoral tissue, and OSCC tissue. This included gingiva-derived MSCs (GMSCs), OSCC adjacent noncancerous tissues-derived MSCs (OSCCN-MSCs), and OSCC-MSCs. The adipogenic and osteogenic differentiation capabilities of these cells were evaluated using Oil Red O and Alizarin Red S staining, respectively. OSCC cells were then co-cultured with either OSCC-MSCs or GMSCs to assess the impact on OSCC cell proliferation and migration. Subcutaneous xenograft experiments were conducted in BALB/c-nu mice to further investigate the effects in vivo. Additionally, immunohistochemical staining was performed on clinical samples to determine the expression levels of fatty acid synthase (FASN) and the proliferation marker Ki67.

RESULTS

OSCC-MSCs exhibited enhanced adipogenic differentiation and reduced osteogenic differentiation compared to GMSCs. OSCC-MSCs significantly increased the proliferation and migration of OSCC cells relative to GMSCs and promoted tumor growth in mouse xenografts. Lipid droplet accumulation in the stroma was significantly more pronounced in OSCC + OSCC-MSCs xenografts compared to OSCC + GMSCs xenografts. Free fatty acids (FFAs) levels were elevated in OSCC tissues compared to normal gingival tissues. Moreover, OSCC-MSCs consistently secreted higher levels of FFAs in condition medium than GMSCs. Knockdown of FASN in OSCC-MSCs reduced their adipogenic potential and inhibited their ability to promote OSCC cell proliferation and migration. Clinical sample analysis confirmed higher FASN expression in OSCC stroma, correlating with larger tumor size and increased Ki67 expression in cancer tissues, and was associated with poorer overall survival.

CONCLUSIONS

OSCC-MSCs promoted OSCC proliferation and migration by upregulating FASN expression and facilitating FFAs secretion. Our results provide new insight into the mechanism of OSCC progression and suggest that the FASN of OSCC-MSCs may be potential targets of OSCC in the future.

CD248 Cleaved Form in Human Colorectal Cancer Stroma: Implications for Tumor Behavior and Prognosis

CD248 (endosialin/tumor endothelial marker 1) is upregulated in cancer, including colorectal cancer (CRC), but its exact role in tumor progression remains to be elucidated. Previous studies have shown that the extracellular domain of CD248 mediates the interaction between tumor cells and extracellular matrix proteins and that interfering with this interaction may reduce tumor invasion and migration activities. We have examined the expression of CD248 in 117 human CRC samples by immunohistochemistry and investigated the association with various clinicopathologic features, including the occurrence of metastasis, intratumoral immune cell density and overall survival. Of the 117 specimens analyzed, 76.1% (89/117) exhibited CD248-high stromal expression, whereas 23.9% (28/117) demonstrated CD248-low stromal expression. Interestingly, we detected the presence of a cleaved form of CD248, which appears to accumulate in the stromal extracellular matrix. A higher metastasis rate (lymph node and distant) was observed in the CD248-low group (21/28, 75.0% vs 44/89, 49.4%; P = .02). In addition, CD248-low tumors had fewer CD163-positive macrophages and FoxP3-positive regulatory T cells (P < .05) with no significant difference in CD8-positive T-cell infiltration and PD-L1 expression between the groups (P > .05). Finally, overall survival was lower in CD248-low tumors than in CD248-high tumors, with 5-year survival rates of 35.7% and 57.3%, respectively (P = .01). In a multivariate analysis, the hazard ratio of CD248-low tumors vs CD248-high tumors was 1.93 (95% CI, 1.09-3.41; P = .02). Our findings suggest that CD248 stromal expression may influence the tumor microenvironment, impacting tumor behavior and prognosis, and can serve as a promising prognostic biomarker in CRC.

Mesenchymal Stem Cells in Cancer Therapy

The mesenchymal stem/stromal cells (MSCs) are multipotent cells that were initially discovered in the bone marrow in the late 1960s but have so far been discovered in almost all tissues of the body. The multipotent property of MSCs enables them to differentiate into various cell types and lineages, such as adipocytes, chondrocytes, and osteocytes. The immunomodulation capacity and tumor-targeting features of MSCs made their use crucial for cell-based therapies in cancer treatment, yet limited advancement could be observed in translational medicine prospects due to the need for more information regarding the controversial roles of MSCs in crosstalk tumors. In this review, we discuss the therapeutic potential of MSCs, the controversial roles played by MSCs in cancer progression, and the anticancer therapeutic strategies that are in association with MSCs. Finally, the clinical trials designed for the direct use of MSCs for cancer therapy or for their use in decreasing the side effects of other cancer therapies are also mentioned in this review to evaluate the current status of MSC-based cancer therapies.

Converging frontiers in cancer treatment: the role of nanomaterials, mesenchymal stem cells, and microbial agents-challenges and limitations

Globally, people widely recognize cancer as one of the most lethal diseases due to its high mortality rates and lack of effective treatment options. Ongoing research into cancer therapies remains a critical area of inquiry, holding significant social relevance. Currently used treatment, such as chemotherapy, radiation, or surgery, often suffers from other problems like damaging side effects, inaccuracy, and the lack of ability to clear tumors. Conventional cancer therapies are usually imprecise and ineffective and usually develop resistance to treatments and cancer recurs. Cancer patients need fresh and innovative treatment that can reduce side effects while maximizing effectiveness. In recent decades several breakthroughs in these, and other areas of medical research, have paved the way for new avenues of fighting cancer including more focused and more effective alternatives. This study reviews exciting possibilities for mesenchymal stem cells (MSCs), nanomaterials, and microbial agents in the modern realm of cancer treatment. Nanoparticles (NPs) have demonstrated surprisingly high potential. They improve drug delivery systems (DDS) significantly, enhance imaging techniques remarkably, and target cancer cells selectively while protecting healthy tissues. MSCs play a double role in tissue repair and are a vehicle for novel cancer treatments such as gene treatments or NPs loaded with therapeutic agents. Additionally, therapies utilizing microbial agents, particularly those involving bacteria, offer an inventive approach to cancer treatment. This review investigates the potential of nanomaterials, MSCs, and microbial agents in addressing the shortcomings of conventional cancer therapies. We will also discuss the challenges and limitations of using these therapeutic approaches.

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.

Exosomes from human bone marrow MSCs alleviate PD-1/PD-L1 inhibitor-induced myocardial injury in melanoma mice by regulating macrophage polarization and pyroptosis

Myocarditis, which can be triggered by immune checkpoint inhibitor (ICI) treatment, represents a critical and severe adverse effect observed in cancer therapy. Thus, elucidating the underlying mechanism and developing effective strategies to mitigate its harmful impact is of utmost importance. The objective of this study is to investigate the potential role and regulatory mechanism of exosomes derived from human bone marrow mesenchymal stem cells (hBMSC-Exos) in providing protection against myocardial injury induced by ICIs. We observed that the administration of programmed death 1/programmed death-ligand 1 (PD-1/PD-L1) inhibitor BMS-1 in tumor-bearing mice led to evident cardiac dysfunction and myocardial injury, which were closely associated with M1 macrophage polarization and cardiac pyroptosis. Remarkably, these adverse effects were significantly alleviated through tail-vein injection of hBMSC-Exos. Moreover, either BMS-1 or hBMSC-Exos alone demonstrated the ability to reduce tumor size, while the combination of hBMSC-Exos with BMS-1 treatment not only effectively improved the probability of tumor inhibition but also alleviated cardiac anomalies induced by BMS-1.

Mesenchymal Stem Cells and Reticulated Platelets: New Horizons in Multiple Myeloma

Multiple myeloma (MM) is a malignant plasma cell disorder characterized by the accumulation of abnormal plasma cells in the bone marrow. Mesenchymal stem cells (MSCs) and reticulated platelets (RPs) have been implicated in the pathogenesis of MM. This narrative review aims to explore the role of MSCs and RPs in the pathophysiology of MM, particularly their clinical use as possible variables of prognostic value in this hematologic neoplasia. The interaction between MSCs and MM cells within the bone marrow microenvironment supports MM cell survival, proliferation, and drug resistance. MSCs contribute to the development and maintenance of MM through the secretion of various factors, including cytokines, chemokines, and growth factors. Moreover, RPs, young and highly reactive platelets, have been implicated in promoting angiogenesis, tumor growth, and metastasis in MM. Several studies show that cells such as MSCs and platelets participate actively in the biology of the disease. Still, in clinical practice, they are not considered part of evaluating affected patients. In this review, we explore the possibility of including the evaluation of MSCs and PRs in the clinical practice for patients with MM as part of the strategies to improve the outcomes of this disease.

Mesenchymal stem cells - the secret agents of cancer immunotherapy: Promises, challenges, and surprising twists

Mesenchymal stem cells (MSCs) are recognized for their immunomodulatory capabilities, tumor-homing abilities, and capacity to serve as carriers for therapeutic agents. This review delves into the role of adoptively transferred MSCs in tumor progression, their interactions with the tumor microenvironment, and their use in delivering anti-cancer drugs, oncolytic viruses, and genetic material. It also addresses the challenges and limitations associated with MSC therapy, such as variability in MSC preparations and potential tumorigenic effects emphasizing the need for advanced genetic engineering and personalized approaches to enhance therapeutic efficacy. The review concludes with an optimistic outlook on the future of MSC-based therapies, underscoring their promise to develop effective and personalized cancer treatments.

Harnessing the Therapeutic Potential of Mesenchymal Stem Cells in Cancer Treatment

Cancer, as a complicated disease, is considered to be one of the major leading causes of death globally. Although various cancer therapeutic strategies have been established, however, some issues confine the efficacies of the treatments. In recent decades researchers for finding efficient therapeutic solutions have extensively focused on the abilities of stem cells in cancer inhibition. Mesenchymal stem cells (MSCs) are multipotent stromal cells that can the most widely extracted from various sources such as the bone marrow (BM), placenta, umbilical cord (UC), menses blood, Wharton's jelly (WJ), adipose tissue and dental pulp (DP). These cells are capable of differentiating into the osteoblasts, chondrocytes, and adipocytes. Due to the unique characteristics of MSCs such as paracrine effects, immunomodulation, tumor-tropism, and migration, they are considered promising candidates for cancer therapeutics. Currently, MSCs are an excellent living carrier for delivery of therapeutic genes and chemical agents to target tumor sites. Also, exosomes, the most important extracellular vesicle released from MSCs, act as a strong cell-free tool for cancer therapeutics. MSCs can prevent cancer progression by inhibiting several signaling pathways, such as wnt/β-catenin and PI3K/AKT/mTOR. However, there are several challenges associated with the use of MSCs and their exosomes in the field of therapy that need to be considered. This review explores the significance of MSCs in cell-based therapy, focusing on their homing properties and immunomodulatory characteristics. It also examines the potential of using MSCs as carriers for delivery of anticancer agents and their role in modulating the signal transduction pathways of cancer cells.

The Potential of Human Pulmonary Mesenchymal Stem Cells as Vectors for Radiosensitizing Metallic Nanoparticles: An In Vitro Study

BACKGROUND/OBJECTIVES

Metallic nanoparticles (NPs) exhibit interesting radiosensitizing effects, and finding a way to accurately deliver them appears to be crucial. Due to their tumor tropism, mesenchymal stem cells (MSCs) represent a strategic approach. Therefore, we aimed to evaluate the impact of core-shell Fe3O4@Au NPs on the functionality of human pulmonary MSCs (HPMSCs).

METHODS/RESULTS

The results showed that 100 µg/mL Fe3O4@Au NPs, accumulated in HPMSCs (revealed by Prussian blue staining), did not alter cell viability as assessed by cell counting, MTT, and LDH assays. However, caspase 9 and Bcl2 gene expression, evaluated by RT-qPCR, was regulated 72 h after exposure to the NPs. Moreover, the NPs also decreased proinflammatory cytokine/chemokine secretions, except for CXCL8 (ELISA). These modulations were associated with the downregulation of AMPK gene expression at 24 h. In contrast, the NPs did not modulate VEGF, PI3K, or PDGF gene expression. Nevertheless, a decrease in VEGF secretion was observed after 24 h of exposure to the NPs. Interestingly, the Fe3O4@Au NPs did not modulate Nrf2 gene expression, but they did regulate the expression of the genes encoding Nox4 and HMOX-1. Additionally, the NPs increased ROS production, suggesting a redox imbalance.

CONCLUSIONS

Finally, the Fe3O4@Au NPs did not affect the HPMSCs' viability or proangiogenic/tumorigenic markers. These findings are encouraging for investigating the effects of Fe3O4@Au NPs delivered by HPMSCs to tumor sites in combination with radiation.

Adipose Stem Cells and Their Interplay with Cancer Cells and Mitochondrial Reservoir: A New Promising Target

Adipose-derived stem cells (ASCs) significantly influence tumor progression within the tumor microenvironment (TME). This review examines the pro-tumorigenic roles of ASCs, focusing on paracrine signaling, direct cell-cell interactions, and immunomodulation. ASC-mediated mitochondrial transfer through tunneling nanotubes (TNTs) and gap junctions (GJs) plays a significant role in enhancing cancer cell survival and metabolism. Cancer cells with dysfunctional mitochondria acquire mitochondria from ASCs to meet their metabolic needs and thrive in the TME. Targeting mitochondrial transfer, modulating ASC function, and influencing metabolic pathways are potential therapeutic strategies. However, challenges like TME complexity, specificity, safety concerns, and resistance mechanisms must be addressed. Disrupting the ASC-cancer cell-mitochondria axis offers a promising approach to cancer therapy.

Proliferative Effects of Mesenchymal Stromal Cells on Neuroblastoma Cell Lines: Are They Tumor Promoting or Tumor Inhibiting?

BACKGROUND

Neuroblastoma is a common pediatric malignancy with poor survival for high-risk disease. Mesenchymal stromal cells (MSCs) have innate tumor-homing properties, enabling them to serve as a cellular delivery vehicle, but MSCs have demonstrated variable effects on tumor growth. We compared how placental MSCs (PMSCs) and bone marrow-derived MSCs (BM-MSCs) affect proliferation of neuroblastoma (NB) cells in vitro.

METHODS

Indirect co-culture assessed proliferative effects of 18 MSCs (early-gestation PMSCs (n = 9), term PMSCs (n = 5), BM-MSCs (n = 4) on three high-risk NB cell lines (NB1643, SH-SY5Y, and CHLA90). Controls were NB cells cultured in media alone. Proliferation was assessed using MTS assay and measured by fold change (fc) over controls. PMSCs were sub-grouped by neuroprotective effect: strong (n = 7), intermediate (n = 3), and weak (n = 4). The relationship between MSC type, PMSC neuroprotection, and PMSC gestational age on NB cell proliferation was assessed.

RESULTS

NB cell proliferation varied between MSC groups. BM-MSCs demonstrated lower proliferative effects than PMSCs (fc 1.18 vs 1.44, p < 0.001). Neither gestational age nor neuroprotection significantly predicted degree of proliferation. Proliferative effects of MSCs varied among NB cell lines. BM-MSCs had less effect on CHLA90 (fc 1.01) compared to NB1643 (fc 1.33) and SH-SY5Y (fc 1.20). Only NB1643 showed a difference between early and term PMSCs (p = 0.04).

CONCLUSION

Effects of MSCs on NB cell proliferation vary by MSC source and NB cell line. BM-MSCs demonstrated lower proliferative effects than most PMSCs. MSC neuroprotection was not correlated with proliferation. Improved understanding of MSC proliferation-promoting mechanisms may provide valuable insight into selection of cells best suited as drug delivery vehicles.

LEVEL OF EVIDENCE

N/A.

TYPE OF STUDY

Original Research.

Bioengineered Mesenchymal Stem/Stromal Cells in Anti-Cancer Therapy: Current Trends and Future Prospects

Mesenchymal stem/stromal cells (MSCs) are one of the most widely used cell types in advanced therapies due to their therapeutic potential in the regulation of tissue repair and homeostasis, and immune modulation. However, their use in cancer therapy is controversial: they can inhibit cancer cell proliferation, but also potentially promote tumour growth by supporting angiogenesis, modulation of the immune milieu and increasing cancer stem cell invasiveness. This opposite behaviour highlights the need for careful and nuanced use of MSCs in cancer treatment. To optimize their anti-cancer effects, diverse strategies have bioengineered MSCs to enhance their tumour targeting and therapeutic properties or to deliver anti-cancer drugs. In this review, we highlight the advanced uses of MSCs in cancer therapy, particularly as carriers of targeted treatments due to their natural tumour-homing capabilities. We also discuss the potential of MSC-derived extracellular vesicles to improve the efficiency of drug or molecule delivery to cancer cells. Ongoing clinical trials are evaluating the therapeutic potential of these cells and setting the stage for future advances in MSC-based cancer treatment. It is critical to identify the broad and potent applications of bioengineered MSCs in solid tumour targeting and anti-cancer agent delivery to position them as effective therapeutics in the evolving field of cancer therapy.

Effects of mesenchymal stem cells versus curcumin on sonic hedgehog signaling in experimental model of Hepatocellular Carcinoma

BACKGROUND

Sonic Hedgehog (SHH) is a fundamental signaling pathway that controls tissue reconstruction, stem cell biology, and differentiation and has a role in gut tissue homeostasis and development. Dysregulation of SHH leads to the development of HCC.

METHODS, AND RESULTS

The present study was conducted to compare the effects of mesenchymal stem cells (MSCs) and curcumin on SHH molecular targets in an experimental model of HCC in rats. One hundred rats were divided equally into the following groups: control group, HCC group, HCC group received MSCs, HCC group received curcumin, and HCC group received MSCs and curcumin. Histopathological examinations were performed, and gene expression of SHH signaling target genes (SHH, PTCH1, SMOH, and GLI1) was assessed by real-time PCR in rat liver tissue. Results showed that SHH target genes were significantly upregulated in HCC-untreated rat groups and in MSC-treated groups, with no significant difference between them. Administration of curcumin with or without combined administration of MSCs led to a significant down-regulation of SHH target genes, with no significant differences between both groups. As regards the histopathological examination of liver tissues, both curcumin and MSCs, either through separate use or their combined use, led to a significant restoration of normal liver pathology.

CONCLUSIONS

In conclusion, SHH signaling is upregulated in the HCC experimental model. MSCs do not inhibit the upregulated SHH target genes in HCC. Curcumin use with or without MSCs administration led to a significant down-regulation of SHH signaling in HCC and a significant restoration of normal liver pathology.

Homeostasis and evolution in relation to regeneration and repair

Homeostasis constitutes a key concept in physiology and refers to self-regulating processes that maintain internal stability when adjusting to changing external conditions. It diminishes internal entropy constituting a driving force behind evolution. Natural selection might act on homeostatic regulatory mechanisms and control mechanisms including homeodynamics, allostasis, hormesis and homeorhesis, where different stable stationary states are reached. Regeneration is under homeostatic control through hormesis. Damage to tissues initiates a response to restore the impaired equilibrium caused by mild stress using cell proliferation, cell differentiation and cell death to recover structure and function. Repair is a homeorhetic change leading to a new stable stationary state with decreased functionality and fibrotic scarring without reconstruction of the 3-D pattern. Mechanisms determining entrance of the tissue or organ to regeneration or repair include the balance between innate and adaptive immune cells in relation to cell plasticity and stromal stem cell responses, and redox balance. The regenerative and reparative capacities vary in different species, distinct tissues and organs, and at different stages of development including ageing. Many cell signals and pathways play crucial roles determining regeneration or repair by regulating protein synthesis, cellular growth, inflammation, proliferation, autophagy, lysosomal function, metabolism and metalloproteinase cell signalling. Attempts to favour the entrance of damaged tissues to regeneration in those with low proliferative rates have been made; however, there are evolutionary constraint mechanisms leading to poor proliferation of stem cells in unfavourable environments or tumour development. More research is required to better understand the regulatory processes of these mechanisms.

The Tumor Stroma of Squamous Cell Carcinoma: A Complex Environment That Fuels Cancer Progression

The tumor microenvironment (TME), a complex assembly of cellular and extracellular matrix (ECM) components, plays a crucial role in driving tumor progression, shaping treatment responses, and influencing metastasis. This narrative review focuses on the cutaneous squamous cell carcinoma (cSCC) tumor stroma, highlighting its key constituents and their dynamic contributions. We examine how significant changes within the cSCC ECM-specifically, alterations in fibronectin, hyaluronic acid, laminins, proteoglycans, and collagens-promote cancer progression, metastasis, and drug resistance. The cellular composition of the cSCC TME is also explored, detailing the intricate interplay of cancer-associated fibroblasts (CAFs), mesenchymal stem cells (MSCs), endothelial cells, pericytes, adipocytes, and various immune cell populations. These diverse players modulate tumor development, angiogenesis, and immune responses. Finally, we emphasize the TME's potential as a therapeutic target. Emerging strategies discussed in this review include harnessing the immune system (adoptive cell transfer, checkpoint blockade), hindering tumor angiogenesis, disrupting CAF activity, and manipulating ECM components. These approaches underscore the vital role that deciphering TME interactions plays in advancing cSCC therapy. Further research illuminating these complex relationships will uncover new avenues for developing more effective treatments for cSCC.

Mesenchymal Stem Cells in the Treatment of COVID-19

Since the emergence of the coronavirus disease 2019 (COVID-19) pandemic, many lives have been tragically lost to severe infections. The COVID-19 impact extends beyond the respiratory system, affecting various organs and functions. In severe cases, it can progress to acute respiratory distress syndrome (ARDS) and multi-organ failure, often fueled by an excessive immune response known as a cytokine storm. Mesenchymal stem cells (MSCs) have considerable potential because they can mitigate inflammation, modulate immune responses, and promote tissue regeneration. Accumulating evidence underscores the efficacy and safety of MSCs in treating severe COVID-19 and ARDS. Nonetheless, critical aspects, such as optimal routes of MSC administration, appropriate dosage, treatment intervals, management of extrapulmonary complications, and potential pediatric applications, warrant further exploration. These research avenues hold promise for enriching our understanding and refining the application of MSCs in confronting the multifaceted challenges posed by COVID-19.