Imaging-Based Efficacy Evaluation of Cancer Immunotherapy in Engineered Tumor Platforms and Tumor Organoids

Cancer immunotherapy is used to treat tumors by modulating the immune system. Although the anticancer efficacy of cancer immunotherapy has been evaluated prior to clinical trials, conventional in vivo animal and endpoint models inadequately replicate the intricate process of tumor elimination and reflect human-specific immune systems. Therefore, more sophisticated models that mimic the complex tumor-immune microenvironment must be employed to assess the effectiveness of immunotherapy. Additionally, using real-time imaging technology, a step-by-step evaluation can be applied, allowing for a more precise assessment of treatment efficacy. Here, an overview of the various imaging-based evaluation platforms recently developed for cancer immunotherapeutic applications is presented. Specifically, a fundamental technique is discussed for stably observing immune cell-based tumor cell killing using direct imaging, a microwell that reproduces a confined space for spatial observation, a droplet assay that facilitates cell-cell interactions, and a 3D microphysiological system that reconstructs the vascular environment. Furthermore, it is suggested that future evaluation platforms pursue more human-like immune systems.

The Evaluation of Mass/DNA Copy Number of Mitochondria in Umbilical Cord Blood-derived Hematopoietic Stem Cells Cocultured with MSCs

Over recent decades, UCB has been widely used as an excellent alternative source of HSCs for treating many hematologic disorders. Recent studies suggest using mesenchymal stroma cell co-cultures to increase the number of HSCs prior to transplantation. Considering the critical role of mitochondria in the cell's fate and the importance of the self-renewal capacity of HSCs in HSCT, we decided to investigate the mass/DNA copy number of mitochondria in HSCs while co-cultured with MSCs and alone after seven days. UCB units were collected from full-term deliveries. MSCs and HSCs were isolated from UCB and the purity of cells was confirmed by flow cytometry. The mtDNA-Copy Number of HSCs was calculated using prob-based real-time PCR. Furthermore, Mito Tracker Green dye measured the mass of mitochondria of HSCs. HSCs from MSC co-culture group showed significantly fewer mtDNA-CN compared to HSCs alone after seven days (p < 0.001). Besides, by comparing the two groups on day seven to HSCs on day zero, we observed a mild increase in the mitochondrial mass of HSCs alone compared to the MSC-HSC co-culture group (p < 0.05). Concerning previous studies that have proved the association between lower mass/DNA-copy number of mitochondria in CD34 + HSCs and lower metabolic activity along with higher quiescence maintenance, and by considering the results of this experiment, it seems that the MSC-HSC co-cultures might be associated with a higher expansion of HSCs as well as stemness maintenance leading to the improvement in engraftment. Nevertheless, further investigations are required to clarify the exact connection between lower mass/DNA-copy number of mitochondria and stemness maintenance in HSCs.

Enhancing osteogenic differentiation of diabetic tendon stem/progenitor cells through hyperoxia: Unveiling ROS/HIF-1α signalling axis

Diabetic calcific tendinopathy is the leading cause of chronic pain, mobility restriction, and tendon rupture in patients with diabetes. Tendon stem/progenitor cells (TSPCs) have been implicated in the development of diabetic calcified tendinopathy, but the molecular mechanisms remain unclear. This study found that diabetic tendons have a hyperoxic environment, characterized by increased oxygen delivery channels and carriers. In hyperoxic environment, TSPCs showed enhanced osteogenic differentiation and increased levels of reactive oxygen species (ROS). Additionally, hypoxia-inducible factor-1a (HIF-1a), a protein involved in regulating cellular responses to hyperoxia, was decreased in TSPCs by the ubiquitin-proteasome system. By intervening with antioxidant N-acetyl-L-cysteine (NAC) and overexpressing HIF-1a, we discovered that blocking the ROS/HIF-1a signalling axis significantly inhibited the osteogenic differentiation ability of TSPCs. Animal experiments further confirmed that hyperoxic environment could cause calcification in the Achilles tendon tissue of rats, while NAC intervention prevented calcification. These findings demonstrate that hyperoxia in diabetic tendons promotes osteogenic differentiation of TSPCs through the ROS/HIF-1a signalling axis. This study provides a new theoretical basis and research target for preventing and treating diabetic calcified tendinopathy.

A review of the potential of induced pluripotent stem cell-derived exosome as a novel treatment for male infertility

Exosomes are a subset of Extracellular vesicles (EVs) released by most cells in the body and can play a significant role in the intercellular connection. Researchers today claim that exosomes secreted by induced pluripotent stem cells (iPSCs) alone can play the same role as direct cell transplantation and, unlike iPSCs, do not lead to tumorigenesis. As a result, iPSC-derived exosomes (iPSC-Exos) have many applications in cell-free treatments and therapeutic effects on various diseases. Male infertility due to a defect or deficiency of spermatogonia to maintain spermatogenesis is one of the diseases that iPSC-Exos seems to be a new way to cure. However, the studies on the effect of iPSC-Exos on male infertility are very limited. In this review, we intend to provide a broader perspective on understanding the mechanisms of iPSC-Exos on spermatogenesis by collecting and reviewing some of the research conducted in this field.

Unveiling the Neurodegenerative Alterations through Oral Stem Cells

Parkinson's disease (PD) is a neurodegenerative condition characterized by the progressive and selective loss of dopaminergic (DAergic) neurons in the midbrain. The replacement of neuromelanin (NM)-containing DAergic neurons in the substantia nigra and the enhancement of NM concentration could offer a promising and safe approach to treating PD symptoms. The objective of this study was to investigate and compare the potential of human periapical-cysts mesenchymal stem cells (hPCy-MSCs) and dental pulp stem cells (DPSCs) to differentiate into DAergic NM-producing neurons and to generate functional 3-dimensional (3D) midbrain-like organoids in vitro. We assessed the changes in morphology and behavior of neuron-like cells (NLCs) as well as the expression of molecular markers characterizing the DAergic neurons. Furthermore, we observed electrically active and functionally mature DAergic neurons by means of electrophysiological assays, NM dosage assays, and the quantification of dopamine release by high-performance liquid chromatography. Our results demonstrate for the first time that both hPCy-MSCs and DPSCs are capable of differentiating into NLCs, further confirmed by the increase in lactate levels in the medium of cells exposed to neurogenic conditions. Importantly, we have induced such NLCs to further differentiate into functional DAergic NM-producing neurons. Finally, 3D midbrain-like organoids have been produced from oral stem cells: they appear as neurosphere-like structures diffusely expressing the neural marker β-III tubulin and containing NM-like granules. Our findings open up a novel and fascinating opportunity to rethink oral stem cells, and the derived 3D disease models, as a strategic and reliable tool for unveiling the neurodegenerative alterations.

Regenerative rehabilitation: a novel multidisciplinary field to maximize patient outcomes

Regenerative rehabilitation is a novel and rapidly developing multidisciplinary field that converges regenerative medicine and rehabilitation science, aiming to maximize the functions of disabled patients and their independence. While regenerative medicine provides state-of-the-art technologies that shed light on difficult-to-treated diseases, regenerative rehabilitation offers rehabilitation interventions to improve the positive effects of regenerative medicine. However, regenerative scientists and rehabilitation professionals focus on their aspects without enough exposure to advances in each other's field. This disconnect has impeded the development of this field. Therefore, this review first introduces cutting-edge technologies such as stem cell technology, tissue engineering, biomaterial science, gene editing, and computer sciences that promote the progress pace of regenerative medicine, followed by a summary of preclinical studies and examples of clinical investigations that integrate rehabilitative methodologies into regenerative medicine. Then, challenges in this field are discussed, and possible solutions are provided for future directions. We aim to provide a platform for regenerative and rehabilitative professionals and clinicians in other areas to better understand the progress of regenerative rehabilitation, thus contributing to the clinical translation and management of innovative and reliable therapies.

Photodynamic therapy with Photoditazine increases microviscosity of cancer cells membrane in cellulo and in vivo

Photodynamic therapy (PDT) is a minimally invasive method for cancer treatment, one of the effects of which is the oxidation of membrane lipids. However, changes in biophysical properties of lipid membranes during PDT have been poorly explored. In this work, we investigated the effects of PDT on membrane microviscosity in cancer cells in the culture and tumor xenografts. Membrane microviscosity was visualized using fluorescence lifetime imaging microscopy (FLIM) with a viscosity-sensitive rotor BODIPY2. It was found that PDT using chlorine e6-based photosensitizer Photoditazine caused a quick, steady elevation of membrane microviscosity both in cellulo and in vivo. The proposed mechanisms responsible for the increase in microviscosity was lipid peroxidation by reactive oxygen species that resulted in a decrease of phosphatidylcholine and the fraction of unsaturated fatty acids in the membranes. Our results suggest that the increased microviscosity is an important factor that contributes to tumor cell damage during PDT.

Intricate relationship between cancer stemness, metastasis, and drug resistance

Cancer stem cells (CSCs) are widely acknowledged as the drivers of tumor initiation, epithelial-mesenchymal transition (EMT) progression, and metastasis. Originating from both hematologic and solid malignancies, CSCs exhibit quiescence, pluripotency, and self-renewal akin to normal stem cells, thus orchestrating tumor heterogeneity and growth. Through a dynamic interplay with the tumor microenvironment (TME) and intricate signaling cascades, CSCs undergo transitions from differentiated cancer cells, culminating in therapy resistance and disease recurrence. This review undertakes an in-depth analysis of the multifaceted mechanisms underlying cancer stemness and CSC-mediated resistance to therapy. Intrinsic factors encompassing the TME, hypoxic conditions, and oxidative stress, alongside extrinsic processes such as drug efflux mechanisms, collectively contribute to therapeutic resistance. An exploration into key signaling pathways, including JAK/STAT, WNT, NOTCH, and HEDGEHOG, sheds light on their pivotal roles in sustaining CSCs phenotypes. Insights gleaned from preclinical and clinical studies hold promise in refining drug discovery efforts and optimizing therapeutic interventions, especially chimeric antigen receptor (CAR)-T cell therapy, cytokine-induced killer (CIK) cell therapy, natural killer (NK) cell-mediated CSC-targeting and others. Ultimately use of cell sorting and single cell sequencing approaches for elucidating the fundamental characteristics and resistance mechanisms inherent in CSCs will enhance our comprehension of CSC and intratumor heterogeneity, which ultimately would inform about tailored and personalized interventions.

Chondrogenic Potential of Umbilical Cord-Derived Mesenchymal Stromal Cells: Insights and Innovations

Background

The advent of tissue engineering and regenerative medicine has introduced innovative approaches to treating degenerative and traumatic injuries, particularly in cartilage, a tissue with limited self-repair capabilities. Among the various stem cell sources, umbilical cord-derived mesenchymal stromal cells (UC-MSCs) have garnered significant interest due to their non-invasive collection, minimal ethical concerns, and robust regenerative potential, particularly in cartilage regeneration.

Methods

A comprehensive literature review was conducted using multiple databases, including PubMed, Scopus, Web of Science, and Google Scholar. Search terms focused on "umbilical cordderived mesenchymal stromal cells," "chondrogenesis," "cartilage regeneration," and related topics. Studies published in the past two decades were included, with selection criteria emphasizing methodological rigor and relevance to UC-MSC chondrogenesis. The review synthesizes findings from various sources to provide a thorough analysis of the potential of UC-MSCs in cartilage tissue engineering.

Results

UC-MSCs exhibit significant chondrogenic potential, supported by their ability to differentiate into chondrocytes under specific conditions. Recent advancements include the development of biomaterial scaffolds and the application of genetic engineering techniques, such as CRISPR/Cas9, to enhance chondrogenic differentiation. Despite these advancements, challenges remain in standardizing cell isolation techniques, scaling up production for clinical use, and ensuring the long-term functionality of regenerated cartilage.

Conclusion

UC-MSCs offer a promising solution for cartilage regeneration in the field of regenerative medicine. Ongoing research is focused on overcoming current challenges through the use of advanced technologies, including bioreactors and gene editing. Collaborative efforts among researchers, clinicians, and bioengineers are essential to translating the potential of UC-MSCs into effective clinical therapies, which could significantly advance tissue regeneration and therapeutic innovation.

Graphical Abstract

The Angiogenic Repertoire of Stem Cell Extracellular Vesicles: Demystifying the Molecular Underpinnings for Wound Healing Applications

Stem cells-derived extracellular vesicles (SC-EVs) have emerged as promising therapeutic agents for wound repair, recapitulating the biological effects of parent cells while mitigating immunogenic and tumorigenic risks. These EVs orchestrate wound healing processes, notably through modulating angiogenesis-a critical event in tissue revascularization and regeneration. This study provides a comprehensive overview of the multifaceted mechanisms underpinning the pro-angiogenic capacity of EVs from various stem cell sources within the wound microenvironment. By elucidating the molecular intricacies governing their angiogenic prowess, we aim to unravel the mechanistic repertoire underlying their remarkable potential to accelerate wound healing. Additionally, methods to enhance the angiogenic effects of SC-EVs, current limitations, and future perspectives are highlighted, emphasizing the significant potential of this rapidly advancing field in revolutionizing wound healing strategies.

Tissue engineering approaches for dental pulp regeneration: The development of novel bioactive materials using pharmacological epigenetic inhibitors

The drive for minimally invasive endodontic treatment strategies has shifted focus from technically complex and destructive root canal treatments towards more conservative vital pulp treatment. However, novel approaches to maintaining dental pulp vitality after disease or trauma will require the development of innovative, biologically-driven regenerative medicine strategies. For example, cell-homing and cell-based therapies have recently been developed in vitro and trialled in preclinical models to study dental pulp regeneration. These approaches utilise natural and synthetic scaffolds that can deliver a range of bioactive pharmacological epigenetic modulators (HDACis, DNMTis, and ncRNAs), which are cost-effective and easily applied to stimulate pulp tissue regrowth. Unfortunately, many biological factors hinder the clinical development of regenerative therapies, including a lack of blood supply and poor infection control in the necrotic root canal system. Additional challenges include a need for clinically relevant models and manufacturing challenges such as scalability, cost concerns, and regulatory issues. This review will describe the current state of bioactive-biomaterial/scaffold-based engineering strategies to stimulate dentine-pulp regeneration, explicitly focusing on epigenetic modulators and therapeutic pharmacological inhibition. It will highlight the components of dental pulp regenerative approaches, describe their current limitations, and offer suggestions for the effective translation of novel epigenetic-laden bioactive materials for innovative therapeutics.

PEG 300 Promotes Mesodermal Differentiation in iPSC-Derived Embryoid Body Formation In Vitro

Embryoid bodies (EB) are sensitive to changes in the culture conditions. Recent studies show that the addition of PEG 300 to culture medium affects cell growth and differentiation; however, its effect on the embryoid body is unclear. This study aims to understand the role of PEG 300 in the process of EB formation and germ layer differentiation. EBs formed more efficiently and differentiated toward the mesoderm when cultured in a medium supplemented with appropriate concentrations of PEG 300. The expression of T/Bry, a marker of mesodermal differentiation, increases in EBs in the PEG group, and the expression of TUBB3 generally decreases, showing a quantitative relationship with PEG. Furthermore, further differentiation of PEG-pretreated EB into vascular smooth muscle cells (VSMCs) by directional induction shows that PEG 300-pretreated induced VSMCs have higher expression of phenotypic markers and greater secretory and contractile functions. This study highlights the role of PEG 300 in the culture medium during EB differentiation, which can significantly enhance mesodermal gene expression and the efficiency of subsequent differentiation into smooth muscle cells and other target cells.

Exosomes derived from tendon stem/progenitor cells enhance tendon-bone interface healing after rotator cuff repair in a rat model

The rate of retear after surgical repair remains high. Mesenchymal stem cells (MSCs) have been extensively employed in regenerative medicine for several decades. However, safety and ethical concerns constrain their clinical application. Tendon Stem/Progenitor Cells (TSPCs)-derived exosomes have emerged as promising cell-free therapeutic agents. Therefore, urgent studies are needed to investigate whether TSPC-Exos could enhance tendon-bone healing and elucidate the underlying mechanisms. In this study, TSPC-Exos were found to promote the proliferation, migration, and expression of fibrogenesis markers in BMSCs. Furthermore, TSPC-Exos demonstrated an ability to suppress the polarization of M1 macrophages while promoting M2 macrophage polarization. In a rat model of rotator cuff repair, TSPC-Exos modulated inflammation and improved the histological structure of the tendon-bone interface, the biomechanical properties of the repaired tendon, and the function of the joint. Mechanistically, TSPC-Exos exhibited high expression of miR-21a-5p, which regulated the expression of PDCD4. The PDCD4/AKT/mTOR axis was implicated in the therapeutic effects of TSPC-Exos on proliferation, migration, and fibrogenesis in BMSCs. This study introduces a novel approach utilizing TSPC-Exos therapy as a promising strategy for cell-free therapies, potentially benefiting patients with rotator cuff tear in the future.

Bone marrow derived mesenchymal stem cells restored GLUT1 expression in the submandibular salivary glands of ovariectomized rats

OBJECTIVE

Loss of ovarian function in menopause is commonly associated with salivary gland dysfunction. The aim is to study the possible therapeutic effect of bone marrow mesenchymal stem cells (BM-MSCs) on the altered structure of the submandibular salivary glands (SMGs) of ovariectomized rats.

DESIGN

Twenty-four female, adult, Wistar rats were used and distributed into three groups (8 rats/group). The control group included sham-operated rats. The ovariectomized group consisted of rats with removed ovaries. The third group consisted of ovariectomized rats received injections, via tail, of MSCs extracted from bone marrow of 3-weeks-old rat hind limb (BM-MSC group). Four weeks after BM-MSC transplantation, the bone mineral density (BMD) of the femur was detected. The SMG was dissected and processed for histological, immunohistochemical, and histomorphometric analyses.

RESULTS

The ovariectomized rats depicted low BMD in the femur. The SMG acini revealed atrophy. The ductal and acinar cells depicted vacuolization and abnormal nuclear histology. GLUT1 immunostaining was decreased in SMG ducts. The BM-MSC group resumed the normal SMG histology and GLUT1 immunolabelling.

CONCLUSIONS

BM-MSC therapy restored the normal SMG structure and GLUT1 immunostaining in the treated ovariectomized rats, suggesting improved glucose transporting function.

Sustained release of stem cell secretome from nano-villi chitosan microspheres for effective treatment of atopic dermatitis

Canine atopic dermatitis (AD) arises from hypersensitive immune reactions. AD symptoms entail severe pruritus and skin inflammation, with frequent relapses. Consequently, AD patients require continuous management, imposing financial burdens and mental fatigue on pet owners. In this study, we aimed to investigate the therapeutic relevance of secretome from canine adipose tissue-derived mesenchymal stem cells (MSCs), especially after encapsulation in nano-villi chitosan microspheres (CS-MS) to expect improved efficacy. Conditioned media (CM) from MSCs significantly inhibited the proliferation of splenocytes, induced the generation of regulatory T cells, and decreased mast cell degranulation. We found that beneficial soluble factors known to reduce AD symptoms, including transforming growth factor-beta 1, were detectable after sequential concentration and lyophilization of CM. The CS-MS, developed by a phase inversion regeneration method, showed high loading and sustained release of the secretome. Local injection of secretome-loaded CS-MS (ST/SC-MS) effectively reduced clinical severity compared to groups treated with secretome. Histological analysis revealed that ST/SC-MS potently suppressed epidermal hyperplasia, immunocyte infiltration and mast cell activation in the lesion. Taken together, this study presents a novel therapeutic approach exhibiting more potent and prolonged immunoregulatory efficacy of MSC secretome for canine AD treatment.

Rev-erbα regulate neurogenesis through suppression of Sox2 in neuronal cells to regenerate dopaminergic neurons and abates MPP+ induced neuroinflammation

Parkinson's disease is a progressive neurodegenerative disease that affects the motor and non-motor circuits of the brain. Currently, there are no promising therapeutic measures for Parkinson's disease, and most strategies designed to alleviate the Parkinson's disease are palliative. The dearth of therapeutic interventions in Parkinson's disease has driven attention in the search for targets that may augment dopamine secretion, promote differentiation towards dopaminergic neuronal lineage, or aid in neuroprotection from neuronal stress and inflammation, and prevent Parkinson's disease associated motor impairment and behavioural chaos. The study first reports that Rev-erbα plays an important role in regulating the differentiation of undifferentiated neuronal cells towards dopaminergic neurons through abating Sox2 expression in human SH-SY5Y cells. Rev-erbα directly binds to the human Sox2 promoter region and represses their expression to promote differentiation towards dopaminergic neurons. We have reported a novel mechanism of Rev-erbα which effectively abrogates 1-methyl-4-phenylpyridinium induced cytotoxicity, inflammation, and oxidative stress, exerted a beneficial effect on transmembrane potential, and suppressed apoptosis in the neuronal in vitro model of Parkinson's disease. Rev-erbα ligand SR9011 was observed to ease the disease severity in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine induced mouse model of Parkinson's disease. Rev-erbα alleviates the locomotor behavioural impairment, prevents cognitive decline and promotes motor coordination in mice. Administration of Rev-erbα ligand also helps in replenishing the dopaminergic neurons and abrogating the neurotoxin mediated toxicity in an in vitro and in vivo Parkinson's disease model. We conclude that Rev-erbα emerges as a moonlighting nuclear receptor that could be targeted in the treatment and alleviation of Parkinson disease.

Investigating the differential therapeutic efficacy and mechanisms of human umbilical cord mesenchymal stem cells at various passages in osteoarthritis treatment

This study aimed to assess the clinical efficacy of umbilical cord mesenchymal stem cells (hUC-MSCs) from different passages (P3, P8, and P13) in the treatment of knee osteoarthritis (OA) and explore the underlying mechanisms. The hUC-MSCs from each passage were characterized and evaluated for their stemness, migration, proliferation, and marker expression. Rats with OA were treated with hUC-MSCs from each passage, and the therapeutic effects were assessed based on knee swelling, discomfort, and pathological examination of the knee joint. Co-culture experiments were conducted to examine the ability of hUC-MSCs to stimulate type II collagen synthesis and inhibit MMP13 expression in chondrocytes. Telomere length and telomerase activity of hUC-MSCs from each passage were measured to investigate the reasons for the observed differences in clinical efficacy. The results revealed that P3 and P8 hUC-MSCs exhibited superior osteogenic and chondrogenic differentiation potential compared to P13, while P13 demonstrated stronger adipogenic differentiation. The wound healing rate was significantly higher in the P3 and P8 groups compared to P13. All hUC-MSC groups expressed high levels of CD90 and CD105, indicating their mesenchymal stem cell characteristics, while CD31 and CD45 were not expressed. CD105 expression was significantly reduced in the P13 group. In the treatment of rat osteoarthritis, there were no significant differences in knee swelling, discomfort, Mankin scores, and pathological findings between P3 and P8 hUC-MSC treatments. However, there was a significant difference between the 8th and 13th passages. Co-culture experiments showed that hUC-MSCs from P3 and P8 enhanced type II collagen synthesis and reduced MMP13 expression in chondrocytes. Although no significant difference was observed between the P3 and P8 groups, a significant difference was found between the P13 and P8 groups. Telomere length analysis revealed that P13 samples had significantly shorter telomeres compared to both P3 and P8. The telomerase activity was positive in P3 and P8 hUC-MSCs, indicating no significant difference between these passages, while it was negative in P13 hUC-MSCs. In conclusion, P3 and P8 hUC-MSCs exhibited superior therapeutic potential for knee osteoarthritis compared to P13, possibly due to their enhanced differentiation capacity and telomerase activity.

Application trends and strategies of hydrogel delivery systems in intervertebral disc degeneration: A bibliometric review

Hydrogels are widely used to explore emerging minimally invasive strategies for intervertebral disc degeneration (IVDD) due to their suitability as drug and cell delivery vehicles. There has been no review of the latest research trends and strategies of hydrogel delivery systems in IVDD for the last decade. In this study, we identify the application trends and strategies in this field through bibliometric analysis, including aspects such as publication years, countries and institutions, authors and publications, and co-occurrence of keywords. The results reveal that the literature in this field has been receiving increasing attention with a trend of growth annually. Subsequently, the hotspots of hydrogels in this field were described and discussed in detail, and we proposed the "four core factors", hydrogels, cells, cell stimulators, and microenvironmental regulation, required for a multifunctional hydrogel for IVDD. Finally, we discuss the popular and emerging mechanistic strategies of hydrogel therapy for IVDD in terms of five aspects: fundamental pathologic changes in IVDD, counteracting cellular senescence, counteracting cell death, improving organelle function, and replenishing exogenous cells. This study provides a reference and a new perspective for future research in this urgently needed field.

Engineered Mesenchymal Stem Cells as Treatment for Cancers: Opportunities, Clinical Applications and Challenges

The insufficient and unspecific target of classical chemotherapies often leads to therapy resistance and cancer recurrence. Over the past decades, discoveries about mesenchymal stem cell (MSC) biology have provided new potential approaches to improve cancer therapy. Researchers have utilised the multipotent, regenerative and immunosuppressive qualities of MSCs and tropisms towards inflammatory, hypoxic and malignant sites in various therapeutic applications. Although MSC-based therapies have generally been demonstrated safe, their effectiveness remains limited when these cells are used alone. However, through genetic engineering, researchers have proven that MSCs can be modified to have specialised delivery roles to increase their therapeutic efficacy in cancer treatment. They can be made to overexpress therapeutic proteins through viral or non-viral genetic modification, which enhances their innate properties. Nevertheless, these engineering strategies must be optimised to increase therapeutic efficacy and targeting effectiveness while minimising any loss of MSC function. This review underscores the cutting-edge methods for engineering MSCs, discusses their promise and the difficulties in translating them into clinical settings, and offers some prospective suggestions for the future on achieving their full therapeutic potential.

NPTX1 Mediates the Facilitating Effects of Hypoxia-Stimulated Human Adipocytes on Adipose-Derived Stem Cell Activation and Autologous Adipose Graft Survival Rate

BACKGROUND

Autologous adipose tissue is an ideal material for soft tissue filling and transplantation; however, high volumes of fat absorption over time lead to a relatively low overall survival percentage. The survival and differentiation of adipose-derived stem cells (ADSCs) in the transplanted microenvironment might improve adipose graft survival. Adipocytes have been reported to affect ADSC activation. However, its underlying mechanisms remain unclear.

METHODS

Human ADSCs were incubated in a culture medium supplemented with hypoxic or normoxic conditioned culture medium (CM) derived from human adipocytes. Neuronal Pentraxin 1 (NPTX1) was overexpressed or knocked down in human adipocytes using an overexpression vector (NPTX1 OE) or small interfering RNA (siRNA) transfection, respectively. ADSC differentiation and paracrine secretion were assessed. Nude mice were implanted with human adipocytes and ADSCs. The adipose tissue was subsequently evaluated by histological analysis.

RESULTS

CM from hypoxic-stimulated human adipocytes significantly facilitated the differentiation ability and paracrine levels of ADSCs. NPTX1 was significantly up-regulated in human adipocytes exposed to hypoxic conditions. In vitro, CM derived from hypoxia-stimulated human adipocytes or NPTX1-overexpressing human adipocytes exposed to normoxia promoted ADSC differentiation and paracrine; after silencing NPTX1, the facilitating effects of hypoxia-treated human adipocytes on ADSC activation were eliminated. Similarly, in vivo, the NPTX1 OE + normoxia-CM group saw improved histological morphology and fat integrity, less fibrosis and inflammation, and increased vessel numbers compared with the OE NC + normoxia-CM group; the adipocyte grafts of the si-NC + hypoxia-CM group yielded the most improved histological morphology, fat integrity, and the most vessel numbers. However, these enhancements of ADSC activation and adipose graft survival were partially abolished by NPTX1 knockdown in human adipocytes.

CONCLUSION

NPTX1 might mediate the facilitating effects of hypoxia-stimulated human adipocytes on ADSC activation, thereby improving adipose tissue survival rate after autologous fat transplantation and the effectiveness of autologous fat transplantation through promoting ADSC activation.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Efficacy and Safety of Cell-Assisted Acellular Adipose Matrix Transfer for Volume Retention and Regeneration Compared to Hyaluronic Acid Filler Injection

BACKGROUND

Cell-assisted acellular adipose matrix (AAM) transfer is a novel technique for soft tissue volume restoration, where AAM acts as a scaffold for tissue proliferation and promotes host cell migration, vascularization, and adipogenesis. This study aimed to evaluate the efficacy and safety of in vivo cell-assisted AAM transfer compared to hyaluronic acid (HA) filler injection.

METHODS

Human adipose tissue was used to manufacture AAM, and murine adipose-derived stem cells (ASCs) were prepared. Nude mice were divided into four groups: AAM transfer (AT), ASC-assisted AAM transfer (CAT), HA filler injection (HI), and ASC-assisted HA filler injection (CHI). Eight weeks post-transfer, in vivo graft volume/weight, histology, and gene expression were analyzed to assess efficacy and safety.

RESULTS

The AAM retained its three-dimensional scaffold structure without cellular components. AT/CAT showed lower volume retention than HA/CHA; however, CAT maintained a similar volume to HA. Histologically, adipogenesis and collagen formation were increased in AT/CAT compared to HA/CHA, with CAT showing the highest levels. CAT also demonstrated superior angiogenesis, adipogenesis, and gene expression (Vegf and Pparg), along with lower Il-6 expression, higher Il-10 expression, and reduced capsule formation, indicating better biocompatibility.

CONCLUSIONS

Cell-assisted AAM transfer is a promising technique for volume retention and tissue regeneration, offering a safe and effective alternative to HA filler injections.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

An overview of current research on cancer stem cells: a bibliometric analysis

BACKGROUND

Cancer stem cells (CSCs) represent a potential mechanism contributing to tumorigenesis, metastasis, recurrence, and drug resistance. The objective of this study is to investigate the status quo and advancements in CSC research utilizing bibliometric analysis.

METHODS

Publications related to CSCs from 2010 to 2022 were collected from the Web of Science Core Collection database. Various analytical tools including CiteSpace, VOSviewer, Scimago Graphica, and GraphPad Prism were used to visualize aspects such as co-authorship, co-occurrence, and co-citation within CSC research to provide an objective depiction of the contemporary status and developmental trajectory of the CSC field.

RESULTS

A total of 22,116 publications were included from 1942 journals written by 95,992 authors. Notably, China emerged as the country with the highest number of publications, whereas the United States exerted the most significant influence within the field. MD Anderson Cancer Center emerged as the institution making the most comprehensive contributions. Wicha M.S. emerged as the most prolific and influential researcher. Among journals, Cancers emerged as a focal point for CSC research, consistently publishing a wealth of high-quality papers. Furthermore, it was observed that most journals tended to approach CSC research from molecular, biological, and immunological perspectives. The research into CSCs encompassed a broad array of topics, including isolation and enrichment techniques, biomarkers, biological characteristics, cancer therapy strategies, and underlying biological regulatory mechanisms. Notably, exploration of the tumor microenvironment and extracellular vesicles emerged as burgeoning research frontiers for CSCs.

CONCLUSION

The research on CSCs has garnered growing interest. A trend toward multidisciplinary homogeneity is emerging within the realm of CSCs. Further investigation could potentially center on the patients of extracellular vesicles and the tumor microenvironment in relation to CSCs.

Dtx2 Deficiency Induces Ependymo-Radial Glial Cell Proliferation and Improves Spinal Cord Motor Function Recovery

Traumatic injury to the spinal cord can lead to significant, permanent disability. Mammalian spinal cords are not capable of regeneration; in contrast, adult zebrafish are capable of such regeneration, fully recovering motor function. Understanding the mechanisms underlying zebrafish neuroregeneration may provide useful information regarding endogenous regenerative potential and aid in the development of therapeutic strategies in humans. DELTEX proteins (DTXs) regulate a variety of cellular processes. However, their role in neural regeneration has not been described. We found that zebrafish dtx2, encoding Deltex E3 ubiquitin ligase 2, is expressed in ependymo-radial glial cells in the adult spinal cord. After spinal cord injury, the heterozygous dtx2 mutant fish motor function recovered quicker than that of the wild-type controls. The mutant fish displayed increased ependymo-radial glial cell proliferation and augmented motor neuron formation. Moreover, her gene expression, downstream of Notch signaling, increased in Dtx2 mutants. Notch signaling inactivation by dominant-negative Rbpj abolished the increased ependymo-radial glia proliferation caused by Dtx2 deficiency. These results indicate that ependymo-radial glial proliferation is induced by Dtx2 deficiency by activating Notch-Rbpj signaling to improve spinal cord regeneration and motor function recovery.

Reduction of Oxidative Stress and Excitotoxicity by Mesenchymal Stem Cell Biomimetic Co-Delivery System for Cerebral Ischemia-Reperfusion Injury Treatment

A cerebral ischemia-reperfusion injury is ensued by an intricate interplay between various pathological processes including excitotoxicity, oxidative stress, inflammation, and apoptosis. For a long time, drug intervention policies targeting a single signaling pathway have failed to achieve the anticipated clinical efficacy in the intricate and dynamic inflammatory environment of the brain. Moreover, inadequate targeted drug delivery remains a significant challenge in cerebral ischemia-reperfusion injury therapy. In this study, a multifunctional nanoplatform (designated as PB-006@MSC) is developed using ZL006-loaded Prussian blue nanoparticles (PBNPs) camouflaged by a mesenchymal stem cell (MSC) membrane (MSCm). ZL006 is a neuroprotectant. It can be loaded efficiently into the free radical scavenger PBNP through mesoporous adsorption. This can simultaneously modulate multiple targets and pathways. MSCm biomimetics can reduce the nanoparticle immunogenicity, efficiently enhance their homing capability to the cerebral ischemic penumbra, and realize active-targeting therapy for ischemic stroke. In animal experiments, PB-006@MSC integrated reactive oxygen species (ROS) scavenging and neuroprotection. Thereby, it selectively targeted the cerebral ischemic penumbra (about fourfold higher accumulation at 24 h than in the non-targeted group), demonstrated a remarkable therapeutic efficacy in reducing the volume of cerebral infarction (from 37.1% to 2.3%), protected the neurogenic functions, and ameliorated the mortality.

Heterogeneity in Dental Tissue-Derived MSCs Revealed by Single-Cell RNA-seq

Mesenchymal stromal cells (MSCs) are multipotent, progenitor cells that reside in tissues across the human body, including the periodontal ligament (PDL) and gingiva. They are a promising therapeutic tool for various degenerative and inflammatory diseases. However, different heterogeneity levels caused by tissue-to-tissue and donor-to-donor variability, and even intercellular differences within a given MSCs population, restrict their therapeutic potential. There are considerable efforts to decipher these heterogeneity levels using different "omics" approaches, including single-cell transcriptomics. Previous studies applied this approach to compare MSCs isolated from various tissues of different individuals, but distinguishing between donor-to-donor and tissue-to-tissue variability is still challenging. In this study, MSCs were isolated from the PDL and gingiva of 5 periodontally healthy individuals and cultured in vitro. A total of 3,844 transcriptomes were generated using single-cell mRNA sequencing. Clustering across the 2 different tissues per donor identified PDL- and gingiva-specific and tissue-spanning MSCs subpopulations with unique upregulated gene sets. Gene/pathway enrichment and protein-protein interaction (PPI) network analysis revealed differences restricted to several cellular processes between tissue-specific subpopulations, indicating a limited tissue-of-origin variability in MSCs. Gene expression, pathway enrichment, and PPI network analysis across all donors' PDL- or gingiva-specific subpopulations showed significant but limited donor-to-donor differences. In conclusion, this study demonstrates tissue- and donor-specific variabilities in the transcriptome level of PDL- and gingiva-derived MSCs, which seem restricted to specific cellular processes. Identifying tissue-specific and tissue-spanning subpopulations highlights the intercellular differences in dental tissue-derived MSCs. It could be reasonable to control MSCs at a single-cell level to ensure their properties before transplantation.

Polyamine Anabolism Promotes Chemotherapy-Induced Breast Cancer Stem Cell Enrichment

Breast cancer patients may initially benefit from cytotoxic chemotherapy but experience treatment resistance and relapse. Chemoresistant breast cancer stem cells (BCSCs) play a pivotal role in cancer recurrence and metastasis, however, identification and eradication of BCSC population in patients are challenging. Here, an mRNA-based BCSC signature is developed using machine learning strategy to evaluate cancer stemness in primary breast cancer patient samples. Using the BCSC signature, a critical role of polyamine anabolism in the regulation of chemotherapy-induced BCSC enrichment, is elucidated. Mechanistically, two key polyamine anabolic enzymes, ODC1 and SRM, are directly activated by transcription factor HIF-1 in response to chemotherapy. Genetic inhibition of HIF-1-controlled polyamine anabolism blocks chemotherapy-induced BCSC enrichment in vitro and in xenograft mice. A novel specific HIF-1 inhibitor britannin is identified through a natural compound library screening, and demonstrate that coadministration of britannin efficiently inhibits chemotherapy-induced HIF-1 transcriptional activity, ODC1 and SRM expression, polyamine levels, and BCSC enrichment in vitro and in xenograft and autochthonous mouse models. The findings demonstrate the key role of polyamine anabolism in BCSC regulation and provide a new strategy for breast cancer treatment.

1,25-(OH)2D3 promotes hair growth by inhibiting NLRP3/IL-1β and HIF-1α/IL-1β signaling pathways

Vitamin D is a crucial vitamin that participates in various biological processes through the Vitamin D Receptor (VDR). While there are studies suggesting that VDR might regulate hair growth through ligand-independent mechanisms, the efficacy of Vitamin D in treating hair loss disorders has also been reported. Here, through in vivo experiments in mice, in vitro organ culture of hair follicles, and cellular-level investigations, we demonstrate that 1,25-(OH)2D3 promotes mouse hair regeneration, prolongs the hair follicle anagen, and enhances the proliferation and migration capabilities of dermal papilla cells and outer root sheath keratinocytes in a VDR-dependent manner. Transcriptome analysis of VDR-knockout mouse skin reveals the involvement of HIF-1α, NLRP3, and IL-1β in these processes. Finally, we confirm that 1,25-(OH)2D3 can counteract the inhibitory effects of DHT on hair growth. These findings suggest that 1,25-(OH)2D3 has a positive impact on hair growth and may serve as a potential therapeutic agent for androgenetic alopecia (AGA).

Assessment of therapeutic efficacy of adipose tissue-derived mesenchymal stem cells administration in hyperlipidemia-induced aortic atherosclerosis in adult male albino rats

Atherosclerosis (AS) is a common disease seriously detrimental to human health. AS is a chronic progressive disease related to inflammatory reactions. The present study aimed to characterize and evaluate the effects of adipose tissue stem cells (ADSCs) in high-fat diet-induced atherosclerosis in a rat model. The present study comprises thirty-six rats and they were divided into three groups: the control group, the high-fat diet (HFD) group; which received a high-fat diet, and the high-fat diet + stem cells (HFD+SC) group; which was fed with a high-fat diet along with the administration of intravenous ADSCs. Food was given to the animals for 20 weeks to establish dyslipidemia models. After 20 weeks, animals were sacrificed by cervical dislocation; blood was collected to measure total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL); aortae were collected to detect morphologic changes. Rats of the HFD group showed a significant increase in body weight (B.Wt), altered lipid profile increased expression of inducible nitric oxide synthase (iNOS), and decreased expression of endothelial nitric oxide synthase (eNOS). However, in HFD+SC there was a significant decrease in body weight gain and an improvement in lipid profile. Histopathological and ultrastructural variations observed in the aorta of the HFD group when treated with ADSCs showed preserved normal histological architecture and reduced atherosclerosis compared with the HFD group. This was evidenced by laboratory, histological, immunohistochemical, and morphometric studies. Thus, ADSCs reduced TC, TG, and LDL, reduced the expression of iNOS, and increased the expression of eNOS. The high-fat diet was likely to cause damage to the wall of blood vessels. Systemically transplanted ADSCs could home to the aorta, and further protect the aorta from HFD-induced damage.

Adipocyte-conditioned medium induces tamoxifen resistance by activating PI3K/Akt/mTOR pathway in estrogen receptor-positive breast cancer cells

Resistance to endocrine therapy is a major clinical challenge in estrogen receptor (ER)-positive breast cancer. Obesity is associated with the clinical response to ER-positive breast cancers; however, the mechanism underlying obesity-induced resistance to endocrine therapy in ER-positive breast cancers remains unclear. In this study, we investigated the molecular mechanisms underlying obesity-induced resistance to tamoxifen (TAM), an anti-estrogen agent, in the ER-positive breast cancer cell line MCF-7 using differentiated adipocyte-conditioned medium (D-CM). Treatment of the cells with D-CM promoted TAM resistance by reducing TAM-induced apoptosis. The expression levels of the ERα target genes were higher in D-CM-treated cells than those in untreated ones. In contrast, when the cells were cultured in the presence of TAM, the expression levels were decreased, with or without D-CM. Moreover, the expression of the markers for cancer stem-like cells (CSCs) and mammosphere formation was enhanced by co-treating with D-CM and TAM, compared with TAM alone. The phosphatidylinositol-3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway was activated in MCF-7 cells by D-CM treatment, even in the presence of TAM. Inhibition of the PI3K/Akt/mTOR pathway decreased the expression levels of the CSC markers, suppressed mammosphere formation, and resensitized to TAM via inducing apoptosis in D-CM-treated cells. These results indicate that the conditioned medium of differentiated adipocytes promoted TAM resistance by inducing the CSC phenotype through activation of the PI3K/Akt/mTOR pathway in ER-positive breast cancer cells. Thus, the PI3K/Akt/mTOR pathway may be a therapeutic target in obese patients with ER-positive breast cancers.

Comparative insight into the regenerative mechanisms of the adult brain in zebrafish and mouse: highlighting the importance of the immune system and inflammation in successful regeneration

Regeneration, the complex process of restoring damaged or absent cells, tissues, and organs, varies considerably between species. The zebrafish is a remarkable model organism for its impressive regenerative abilities, particularly in organs such as the heart, fin, retina, spinal cord, and brain. Unlike mammals, zebrafish can regenerate with limited or absent scarring, a phenomenon closely linked to the activation of stem cells and immune cells. This review examines the unique roles played by the immune response and inflammation in zebrafish and mouse during regeneration, highlighting the cellular and molecular mechanisms behind their divergent regenerative capacities. By focusing on zebrafish telencephalic regeneration and comparing it to that of the rodents, this review highlights the importance of a well-controlled, acute, and non-persistent immune response in zebrafish, which promotes an environment conducive to regeneration. The knowledge gained from understanding the mechanisms of zebrafish regeneration holds great promises for the treatment of human neurodegenerative diseases and brain damage (stroke and traumatic brain injuries), as well as for the advancement of regenerative medicine approaches.

Regulation and mechanistic insights into tensile strain in mesenchymal stem cell osteogenic differentiation

Bone marrow mesenchymal stem cells (BMSCs) are integral to bone remodeling and homeostasis, as they are capable of differentiating into osteogenic and adipogenic lineages. This differentiation is substantially influenced by mechanosensitivity, particularly to tensile strain, which is a prevalent mechanical stimulus known to enhance osteogenic differentiation. This review specifically examines the effects of various cyclic tensile stress (CTS) conditions on BMSC osteogenesis. It delves into the effects of different loading devices, magnitudes, frequencies, elongation levels, dimensionalities, and coculture conditions, providing a comparative analysis that aids identification of the most conducive parameters for the osteogenic differentiation of BMSCs. Subsequently, this review delineates the signaling pathways activated by CTS, such as Wnt/β-catenin, BMP, Notch, MAPK, PI3K/Akt, and Hedgehog, which are instrumental in mediating the osteogenic differentiation of BMSCs. Through a detailed examination of these pathways, this study elucidates the intricate mechanisms whereby tensile strain promotes osteogenic differentiation, offering valuable guidance for optimizing therapeutic strategies aimed at enhancing bone regeneration.

Investigation of the Effects of Thymoquinone and Dental Pulp-Derived Mesenchymal Stem Cells on Tibial Bone Defect Models

The thymoquinone obtained from Nigella sativa increases osteoblastic activity and significantly reduces the number of osteoclasts, thereby accelerating bone healing. In addition, mesenchymal stem cells isolated from various tissues are considered a potential cell source for bone regenerative therapies. The aim of this study is to investigate the effectiveness of thymoquinone, a current and novel agent, in combination with mesenchymal stem cells derived from the dental pulp in promoting bone healing. In the study, 28 male Sprague Dawley rats were used. The rats were divided into 4 groups, each consisting of 7 rats: the control group (group 1) (n=7), thymoquinone group (group 2) (n=7), stem cell group (group 3) (n=7), stem cell+thymoquinone group (group 4) (n=7). A bone defect of 4 mm in diameter and 5 mm in length was created in the left tibial bones of all rats with a trephine bur. In group 1, no procedure was applied to the defect area. Group 2 was applied thymoquinone (10 mg/kg) with oral gavage. In group 3, stem cells were used locally to the defect area. In group 4, stem cells and thymoquinone (10 mg/kg) was applied to the defect area. All rats were killed on the 28th day of the experiment. Tibia tissues extracted during sacrifice were histomorphologically examined in a fixative solution. Significant differences were found in terms of new bone formation and osteoblastic activity values in the "thymoquinone" ( P <0.05), "stem cell" ( P <0.05), and "stem cell+thymoquinone" ( P <0.05) groups compared to the "control" group. In addition, while there was no significant difference in the "thymoquinone" group compared to these stem cell+thymoquinone group in terms of osteoblastic activity ( P >0.05), the difference in terms of new bone formation was found to be significantly lower. No significant differences among the other groups were observed in new bone formation and osteoblastic activity ( P >0.05). According to the results of our study, stem cell+thymoquinone treatment for bone defects is not only more effective than thymoquinone or stem cell treatment alone but also induces greater development of bone trabeculae, contributes to the matrix and connective tissue formation, and increases the number of osteoblasts and osteocytes involved in bone formation.

SFRP1 reduces neutrophil infiltration and inhibits the Wnt/β-catenin pathway to alleviate oral submucous fibrosis

Oral submucous fibrosis (OSF) is a precancerous condition characterized by oral mucosal atrophy with fibrosis of the submucosal tissue. OSF has a high prevalence, and treatment requires improvement. Our study aims to investigate the role and mechanism of secreted frizzled-related protein 1 (SFRP1) in OSF. We constructed an arecoline-induced OSF mice model. Through Pearson's correlation analysis, we investigated the association between SFRP1 levels and expressions of proteins related to the Wnt/β-catenin signaling pathway, as well as the correlation between SFRP1 levels and the degree of neutrophil infiltration. Moreover, neutrophil infiltration intensity, tissue fibrosis degree, and levels of β-catenin, Cyclin D1, and c-myc were evaluated after SFRP1 overexpression treatment through immunohistochemical and biochemical assays. A Wnt/β-catenin pathway activator was used to investigate the molecular mechanism of SFRP1 in the arecoline-induced OSF cell model. Compared with the control group, mice in the OSF group exhibited increased collagen deposition and more severe fibrosis in the oral mucosal tissue (OMT). In the OMT of OSF mice, the levels of SFRP1 were decreased. The levels of SFRP1 exhibited a negative correlation with the levels of Wnt/β-catenin proteins and neutrophil infiltration in the OMT. Upon SFRP1 overexpression, there was a reduction in neutrophil infiltration and fibrosis in the OMT, as well as inhibition of Wnt/β-catenin-related proteins. In vitro, the Wnt/β-catenin pathway activator further reversed the effect of SFRP1 overexpression on OSF. SFRP1 attenuates OSF by reducing neutrophil infiltration and inhibiting the Wnt/β-catenin pathway.

DNA methylome analysis reveals epigenetic alteration of complement genes in advanced metabolic dysfunction-associated steatotic liver disease

BACKGROUND/AIMS

Blocking the complement system is a promising strategy to impede the progression of metabolic dysfunction-associated steatotic liver disease (MASLD). However, the interplay between complement and MASLD remains to be elucidated. This comprehensive approach aimed to investigate the potential association between complement dysregulation and the histological severity of MASLD.

METHODS

Liver biopsy specimens were procured from a cohort comprising 106 Korean individuals, which included 31 controls, 17 with isolated steatosis, and 58 with metabolic dysfunction-associated steatohepatitis (MASH). Utilizing the Infinium Methylation EPIC array, thorough analysis of methylation alterations in 61 complement genes was conducted. The expression and methylation of nine complement genes in a murine MASH model were examined using quantitative RT-PCR and pyrosequencing.

RESULTS

Methylome and transcriptome analyses of liver biopsies revealed significant (P<0.05) hypermethylation and downregulation of C1R, C1S, C3, C6, C4BPA, and SERPING1, as well as hypomethylation (P<0.0005) and upregulation (P<0.05) of C5AR1, C7, and CD59, in association with the histological severity of MASLD. Furthermore, DNA methylation and the relative expression of nine complement genes in a MASH diet mouse model aligned with human data.

CONCLUSION

Our research provides compelling evidence that epigenetic alterations in complement genes correlate with MASLD severity, offering valuable insights into the mechanisms driving MASLD progression, and suggests that inhibiting the function of certain complement proteins may be a promising strategy for managing MASLD.

Ovarian microenvironment: challenges and opportunities in protecting against chemotherapy-associated ovarian damage

BACKGROUND

Chemotherapy-associated ovarian damage (CAOD) is one of the most feared short- and long-term side effects of anticancer treatment in premenopausal women. Accumulating detailed data show that different chemotherapy regimens can lead to disturbance of ovarian hormone levels, reduced or lost fertility, and an increased risk of early menopause. Previous studies have often focused on the direct effects of chemotherapeutic drugs on ovarian follicles, such as direct DNA damage-mediated apoptotic death and primordial follicle burnout. Emerging evidence has revealed an imbalance in the ovarian microenvironment during chemotherapy. The ovarian microenvironment provides nutritional support and transportation of signals that stimulate the growth and development of follicles, ovulation, and corpus luteum formation. The close interaction between the ovarian microenvironment and follicles can determine ovarian function. Therefore, designing novel and precise strategies to manipulate the ovarian microenvironment may be a new strategy to protect ovarian function during chemotherapy.

OBJECTIVE AND RATIONALE

This review details the changes that occur in the ovarian microenvironment during chemotherapy and emphasizes the importance of developing new therapeutics that protect ovarian function by targeting the ovarian microenvironment during chemotherapy.

SEARCH METHODS

A comprehensive review of the literature was performed by searching PubMed up to April 2024. Search terms included 'ovarian microenvironment' (ovarian extracellular matrix, ovarian stromal cells, ovarian interstitial, ovarian blood vessels, ovarian lymphatic vessels, ovarian macrophages, ovarian lymphocytes, ovarian immune cytokines, ovarian oxidative stress, ovarian reactive oxygen species, ovarian senescence cells, ovarian senescence-associated secretory phenotypes, ovarian oogonial stem cells, ovarian stem cells), terms related to ovarian function (reproductive health, fertility, infertility, fecundity, ovarian reserve, ovarian function, menopause, decreased ovarian reserve, premature ovarian insufficiency/failure), and terms related to chemotherapy (cyclophosphamide, lfosfamide, chlormethine, chlorambucil, busulfan, melphalan, procarbazine, cisplatin, doxorubicin, carboplatin, taxane, paclitaxel, docetaxel, 5-fluorouraci, vincristine, methotrexate, dactinomycin, bleomycin, mercaptopurine).

OUTCOMES

The ovarian microenvironment shows great changes during chemotherapy, inducing extracellular matrix deposition and stromal fibrosis, angiogenesis disorders, immune microenvironment disturbance, oxidative stress imbalances, ovarian stem cell exhaustion, and cell senescence, thereby lowering the quantity and quality of ovarian follicles. Several methods targeting the ovarian microenvironment have been adopted to prevent and treat CAOD, such as stem cell therapy and the use of free radical scavengers, senolytherapies, immunomodulators, and proangiogenic factors.

WIDER IMPLICATIONS

Ovarian function is determined by its 'seeds' (follicles) and 'soil' (ovarian microenvironment). The ovarian microenvironment has been reported to play a vital role in CAOD and targeting the ovarian microenvironment may present potential therapeutic approaches for CAOD. However, the relation between the ovarian microenvironment, its regulatory networks, and CAOD needs to be further studied. A better understanding of these issues could be helpful in explaining the pathogenesis of CAOD and creating innovative strategies for counteracting the effects exerted on ovarian function. Our aim is that this narrative review of CAOD will stimulate more research in this important field.

REGISTRATION NUMBER

Not applicable.

In situ forming hydrogels based on modified gellan gum/chitosan for ocular drug delivery of timolol maleate

In situ forming hydrogels are suitable candidates for increasing drug residence time in ocular drug delivery. In this study, gellan gum (GG) was oxidized to form aldehyde groups and in situ gelling hydrogels were synthesized based on a Schiff-base reaction between oxidized GG (OGG) and chitosan (CS) in the presence of β-glycerophosphate. The effect of OGG and CS concentration on the physical and chemical properties of the resulting hydrogels was investigated. The FT-IR spectroscopy confirmed the chemical modification of OGG as well as the functional groups of the prepared hydrogels. The scanning electron microscope (SEM) revealed the highly porous structure of hydrogels. The obtained hydrogels indicated a high swelling degree and degradability. Also, the rheological studies demonstrated self-healing behavior, shear thinning, thixotropy, and mucoadhesion properties for the developed hydrogels. The results of in vitro and ex vivo studies showed that the timolol-loaded hydrogel with a higher amount of OGG has a higher release rate. Moreover, the MTT cytotoxicity test on bone marrow mesenchymal stem cells (BMSCs) confirmed that developed hydrogels are not toxic. The obtained results revealed that the developed hydrogels can be a desirable choice for the ocular drug delivery of timolol in the treatment of glaucoma.

Photobiomodulation and low-intensity pulsed ultrasound synergistically enhance dental mesenchymal stem cells viability, migration and differentiation: an invitro study

Novel methods and technologies that improve mesenchymal stem cells (MSCs) proliferation and differentiation properties are required to increase their clinical efficacy. Photobiomodulation (PBM) and low-intensity pulsed ultrasound (LIPUS) are two strategies that can be used to enhance the regenerative properties of dental MSCs. This study evaluated the cytocompatibility and osteo/odontogenic differentiation of dental pulp, periodontal ligament, and gingival MSCs after stimulation by either PBM or LIPUS and their combined effect. MTT assay, cell migration assay, osteo/odontogenic differentiation by AR staining and ALP activity, and expression of osteo/odontogenic markers (OPG, OC, RUNX2, DSPP, DMP1) by RT-qPCR were evaluated. Statistical analysis was performed using ANOVA, followed by Tukey's post hoc test, with a p-value of less than 0.05 considered significant. The results showed that combined stimulation by PBM and LIPUS resulted in significantly the highest viability of MSCs, the fastest migration, the most dense AR staining, the most increased ALP activity, and the most elevated levels of osteogenic and odontogenic markers. The synergetic stimulation of PBM and LIPUS can be utilized in cell-based regenerative approaches to promote the properties of dental MSCs.

METTL3 inhibitor STM2457 impairs tumor progression and enhances sensitivity to anlotinib in OSCC

OBJECTIVES

To investigate the inhibitory effects of STM2457, which is a novel METTL3 (m6A writer) inhibitor, both as a monotherapy and in combination with anlotinib, in the treatment of oral squamous cell carcinoma (OSCC) both in vitro and in vivo.

MATERIALS AND METHODS

The efficacy of STM2457 or STM2457 plus anlotinib was evaluated using two OSCC cell lines by CCK8, transwell, colony formation, would-healing, sphere formation, cell cycle, apoptosis assays, and nude mice tumor xenograft techniques. The molecular mechanism study was carried out by western blotting, qRT-PCR, MeRIP-qPCR, immunofluorescence, and immunohistochemistry.

RESULTS

STM2457 combined with anlotinib enhanced inhibition of cellular survival/proliferation and promotion of apoptosis in vitro. Moreover, this combinatorial approach exerted a notable reduction in stemness properties and EMT (epithelial-mesenchymal transition) features of OSCC cells. Remarkably, in vivo studies validated the efficacy of the combination treatment. Mechanistically, our investigations revealed that the combined action of STM2457 and anlotinib exerted downregulatory effects on EGFR (epidermal growth factor receptor) expression in OSCC cells.

CONCLUSIONS

The combination of STM2457 and anlotinib targeting EGFR exerted a multiple anti-tumor effect. In near future, anlotinib combined with STM2457 may provide a novel insight for the treatment of OSCC.

A Review of Stem Cell Attributes Derived from the Oral Cavity

Oral cavity stem cells (OCSCs) have been the focus of intense scientific efforts due to their accessibility and stem cell properties. The present work aims to compare the different characteristics of 6 types of dental stem cells derived from the oral cavity: dental pulp stem cells (DPSC), stem cells from human exfoliated deciduous teeth (SHED), periodontal ligament stem cells (PDLSC), stem cells from the apical papilla (SCAP), bone marrow mesenchymal stem cells (BMSC), and gingival mesenchymal stem cells (GMSC). Using immunofluorescence and real-time polymerase chain reaction techniques, we analysed the cells for stem cell, differentiation, adhesion, and extracellular matrix markers; the ability to proliferate in vitro; and multilineage differentiation potential. Markers such as vimentin, CD44, alkaline phosphatase, CD146, CD271, CD49f, Oct 3/4, Sox 9, FGF7, nestin, and BMP4 showed significant differences in expression levels, highlighting the heterogeneity and unique characteristics of each cell type. At the same time, we confirmed that all cell types successfully differentiated into osteogenic, chondrogenic, or adipose lineages, with different readiness. In conclusion, our study reveals the distinct properties and potential applications of various dental-derived stem cells. These findings contribute to a deeper understanding of OCSCs and their significance in future clinical applications.

Cancer stem cells: advances in the glucose, lipid and amino acid metabolism

Cancer stem cells (CSCs) are a class of cells with self-renewal and multi-directional differentiation potential, which are present in most tumors, particularly in aggressive tumors, and perform a pivotal role in recurrence and metastasis and are expected to be one of the important targets for tumor therapy. Studies of tumor metabolism in recent years have found that the metabolic characteristics of CSCs are distinct from those of differentiated tumor cells, which are unique to CSCs and contribute to the maintenance of the stemness characteristics of CSCs. Moreover, these altered metabolic profiles can drive the transformation between CSCs and non-CSCs, implying that these metabolic alterations are important markers for CSCs to play their biological roles. The identification of metabolic changes in CSCs and their metabolic plasticity mechanisms may provide some new opportunities for tumor therapy. In this paper, we review the metabolism-related mechanisms of CSCs in order to provide a theoretical basis for their potential application in tumor therapy.

Generation of a Human Induced Pluripotent Stem Cell Line Expressing a Magnetic Resonance Imaging Reporter Gene

The objective of the current study is to develop a new method for tracking transplanted human induced pluripotent stem cells-derived cardiomyocytes (hiPSC-CMs) using magnetic resonance imaging (MRI). The CRISPR/dCas9 activation system is employed to overexpress ferritin heavy chain (FHC) in hiPSC-CMs. The mRNA and protein expression of FHC in hiPSC and hiPSC-CMs significantly increased after transfection. Iron chloride does not affect the cell viability in a concentration range from 0 to 2000 µm. hiPSCs overexpressing FHC (hiPSC- FHCOE) and hiPSC-CMs overexpressing FHC (hiPSC-CM-FHCOE) significantly enhanced cellular uptake of iron chloride but with no changes in electrophysiological properties compared to hiPSC-CM-Control. Furthermore, hiPSC-CM-FHCOE presented robust contrast and lower T2* values, signifying their potential as highly effective candidates for cardiac MRI. Next, hiPSC-CM-FHCOE is injected into mouse hearts and after 3 days of transplantation, MR images are obtained. hiPSC-CM-FHCOE cells exhibited clear signals in the hearts with lower T2* and rapid signal decay. Collectively, data from this proof-of-concept study demonstrated that endogenous labeling with FHC in hiPSC-CMs can be a potent strategy for enhancing the accuracy of cardiac MRI. This technology represents a significant step forward in tracking the transplanted hiPSC-CMs in the hearts of live animals.

Umbilical cord mesenchymal stem cells: A powerful fighter against colon cancer?

Colon cancer (CC) stands as one of the most common malignancies related to the gastrointestinal system, whose increasing incidence and death rates have been reported all over the world. Standard treatments for fighting cancers like CC comprise surgical approaches, chemotherapy, and radiotherapy, which are suggested by clinicians according to patients' conditions and disease stages. However, patients who utilize these modalities may suffer from serious side effects and adverse outcomes, for example, toxicity and tumor recurrence, as well as a low 5-year survival rate. The present shreds of evidence showed that mesenchymal stem cells (MSCs) can have a suitable capacity for treating different health problems, especially neoplasms. These multipotent stem cells can be isolated from several sources, such as the umbilical cord, bone marrow, adipose tissue, and placenta. Among these mesenchymal sources, umbilical cord-MSCs have gathered much attention in scientific societies due to their advantages (e.g., low immunogenicity, lack of ethical problems, and easy collection). These days, the efficacy of umbilical cord-MSCs and umbilical cord-MSCs-based strategies, such as conditioned medium, extracellular vesicles, and exosomes, on CC have been explored, and promising findings have been stated. Therefore, in this review, we aimed to summarize and debate evidence regarding the effects of UC-MSCs and their related products on CC with a focus on molecular and cellular mechanisms involved in its treatment and pathogenesis of this malignant tumor.

Present status and application prospects of green chitin nanowhiskers: A comprehensive review

Petrochemical resources are non-renewable, which has impeded the development of synthetic polymers. The poor degradability of synthetic polymers poses substantial environmental pressure. Additionally, the high cost of synthetic biopolymers with excellent degradation performance limits their widespread application. Thus, it is crucial to seek green, sustainable, low-cost polymers as alternatives to petrochemical-based synthetic polymers and synthetic biopolymers. Chitin is a natural and renewable biopolymer discovered in crustacean shells, insect exoskeletons, and fungal cell walls. Chitin chains consist of crystalline and amorphous regions. Note that various treatments can be employed to remove the amorphous region, enhancing the crystallinity of chitin. Chitin nanowhiskers are a high crystallinity nanoscale chitin product with a high aspect ratio, a large surface area, adjustable surface morphology, and biocompatibility. They discover widespread applications in biomedicine, environmental treatment, food packaging, and biomaterials. Various methods can be utilized for preparing chitin nanowhiskers, including chemical, ionic liquids, deacetylation, and mechanical methods. However, developing an environmentally friendly preparation process remains a big challenge for expanding their applications in different materials and large-scale production. This article comprehensively analyzes chitin nanowhiskers' preparation strategies and their drawbacks. It also highlights the extensive application in different materials and various fields, besides the potential for commercial application.

The New Roles of traf6 Gene Involved in the Development of Zebrafish Liver and Gonads

Traf6, an adaptor protein, exhibits non-conventional E3 ubiquitin ligase activity and was well studied as an important factor in immune systems and cancerogenesis. In mice, the traf6-null caused a perinatal death, so that the underlying pathophysiology of traf6-defeciency is still largely unclear in animals. Here, in the present study, a traf6 knockout zebrafish line (traf6-/-) was generated and could survive until adulthood, providing a unique opportunity to demonstrate the functions of traf6 gene in animals' organogenesis beyond the mouse model. The body of traf6-/- fish was found to be significantly shorter than that of the wildtype (WT). Likewise, a comparative transcriptome analysis showed that 866 transcripts were significantly altered in the traf6-/- liver, mainly involved in the immune system, metabolic pathways, and progesterone-mediated oocyte maturation. Especially, the mRNA expression of the pancreas duodenum homeobox protein 1 (pdx1), glucose-6-phosphatase (g6pcb), and the vitellogenesis genes (vtgs) were significantly decreased in the traf6-/- liver. Subsequently, the glucose was found to be accumulated in the traf6-/- liver tissues, and the meiotic germ cell was barely detected in traf6-/- testis or ovary. The findings of this study firstly implied the pivotal functions of traf6 gene in the liver and gonads' development in fish species.

Adipose tissue-derived mesenchymal stem cells promote the vascularization of pancreatic islets transplanted into decellularized pancreatic skeletons

We have recently developed a model of pancreatic islet transplantation into a decellularized pancreatic tail in rats. As the pancreatic skeletons completely lack endothelial cells, we investigated the effect of co-transplantation of mesenchymal stem cells and endothelial cells to promote revascularization. Decellularized matrix of the pancreatic tail was prepared by perfusion with Triton X-100, sodium dodecyl sulfate and DNase solution. Isolated pancreatic islets were infused into the skeletons via the splenic vein either alone, together with adipose tissue-derived mesenchymal stem cells (adMSCs), or with a combination of adMSCs and rat endothelial cells (rat ECs). Repopulated skeletons were transplanted into the subcutaneous tissue and explanted 9 days later for histological examination. Possible immunomodulatory effects of rat adMSCs on the survival of highly immunogenic green protein-expressing human ECs were also tested after their transplantation beneath the renal capsule. The immunomodulatory effects of adMSCs were also tested in vitro using the Invitrogen Click-iT EdU system. In the presence of adMSCs, the proliferation of splenocytes as a response to phytohaemagglutinin A was reduced by 47% (the stimulation index decreased from 1.7 to 0.9, P = 0.008) and the reaction to human ECs was reduced by 58% (the stimulation index decreased from 1.6 to 0.7, P = 0.03). Histological examination of the explanted skeletons seeded only with the islets showed their partial disintegration and only a rare presence of CD31-positive cells. However, skeletons seeded with a combination of islets and adMSCs showed preserved islet morphology and rich vascularity. In contrast, the addition of syngeneic rat ECs resulted in islet-cell necrosis with only few endothelial cells present. Live green fluorescence-positive endothelial cells transplanted either alone or with adMSCs were not detected beneath the renal capsule. Though the adMSCs significantly reduced in vitro proliferation stimulated by either phytohaemagglutinin A or by xenogeneic human ECs, in vivo co-transplanted adMSCs did not suppress the post-transplant immune response to xenogeneic ECs. Even in the syngeneic model, ECs co-transplantation did not lead to sufficient vascularization in the transplant area. In contrast, islet co-transplantation together with adMSCs successfully promoted the revascularization of extracellular matrix in the subcutaneous tissue.

JARID2 activation by NFYA promotes stemness of triple-negative breast cancer cells through the PI3K/AKT pathway

BACKGROUND

This study aimed to investigate the role of Jumonji AT Rich Interacting Domain 2 (JARID2) in regulating triple-negative breast cancer (TNBC) stemness and its mechanism.

RESEARCH DESIGN AND METHODS

Bioinformatics analysis examined JARID2 expression, prognosis, and transcription factors. Quantitative polymerase chain reaction, western blot, and immunohistochemistry detected expression. Dual luciferase reporter gene and chromatin immunoprecipitation assays verified binding. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and colony formation assay detected viability and proliferation. Sphere formation assay detected the sphere formation efficiency. Flow cytometry detected CD44+/CD24- -marked stem cells. A xenograft tumor model verified the effect of JARID2 in vivo.

RESULTS

JARID2 and nuclear transcription factor Y subunit α (NFYA) were upregulated in TNBC tissues and positively correlated. Knockdown of JARID2 or NFYA inhibited cell stemness by inhibiting the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (PKB/AKT) signaling pathway. Enforced JARID2 expression rescued the suppressive effect of NFYA knockdown on the PI3K/AKT signaling pathway and cell stemness. Knockdown of JARID2 inhibited tumor growth and cell stemness in mice but was alleviated by concurrent overexpression of NFYA.

CONCLUSIONS

NFYA promotes TNBC cell stemness by upregulating JARID2 expression and regulating the PI3K/AKT signaling pathway, suggesting JARID2 as a potential target for innovating drugs that target TNBC stem cells.

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.

Research on the role of exosomes secreted by immortalized adipose-derived mesenchymal stem cells differentiated into pericytes in the repair of high glucose-induced retinal vascular endothelial cell damage

Diabetic retinopathy, a leading cause of vision impairment, is marked by microvascular complications in the retina, including pericyte loss, a key indicator of early-stage disease. This study explores the therapeutic potential of exosomes derived from immortalized adipose-mesenchymal stem cells differentiated into pericyte-like cells in restoring the function of mouse retinal microvascular endothelial cells damaged by high glucose conditions, thereby contributing to the understanding of early diabetic retinopathy intervention strategies. To induce immortalized adipose-mesenchymal stem cells differentiation into pericyte-like cells, the study employed pericyte growth supplement. And confirmed the success of cell differentiation through the detection of α-smooth muscle actin and neural/glial antigen 2 expression by Western blot and immunofluorescence. Exosomes were isolated from the culture supernatant of immortalized adipose-mesenchymal stem cells using ultracentrifugation and characterized through Western blot for exosomal markers (CD9, CD81, and TSG101), transmission electron microscopy, and nanoparticle tracking analysis. Their influence on mouse retinal microvascular endothelial cells under high glucose stress was assessed through various functional assays. Findings revealed that exosomes, especially those from pericyte-like immortalized adipose-mesenchymal stem cells, were efficiently internalized by retinal microvascular endothelial cells and effectively counteracted high glucose-induced apoptosis. These exosomes also mitigated the rise in reactive oxygen species levels and suppressed the migratory and angiogenic properties of retinal microvascular endothelial cells, as demonstrated by Transwell and tube formation assays, respectively. Furthermore, they preserved endothelial barrier function, reducing hyperglycemia-induced permeability. At the molecular level, qRT-PCR analysis showed that exosome treatment modulated the expression of critical genes involved in angiogenesis (VEGF-A, ANG2, MMP9), inflammation (IL-1β, TNF-α), gap junction communication (CX43), and cytoskeletal regulation (ROCK1), with the most prominent effects seen with exosomes from pericyte-like immortalized adipose-mesenchymal stem cells. High glucose increased the expression of pro-angiogenic and pro-inflammatory markers, which were effectively normalized post-exosome treatment. In conclusion, this research highlights the reparative capacity of exosomes secreted by pericyte-like differentiated immortalized adipose-mesenchymal stem cells in reversing the detrimental effects of high glucose on retinal microvascular endothelial cells. By reducing apoptosis, oxidative stress, inflammation, and abnormal angiogenic behavior, these exosomes present a promising avenue for therapeutic intervention in early diabetic retinopathy. Future studies can focus on elucidating the precise molecular mechanisms and exploring their translational potential in vivo.