Stem cell transplantation (SCT) holds significant promise for regenerative medicine, yet immune rejection remains a major obstacle. To address this, recent advances leverage CRISPR/Cas9 to engineer hypoimmunogenic induced pluripotent stem cells. These modified cells lack classical immune recognition markers (HLA class I/II) yet retain immune-tolerant molecules such as HLA-E, HLA-G, and CD47, enabling their universal use across different individuals. Additionally, mesenchymal stem cell-derived exosomes and immune checkpoint modulators (e.g., PD-L1) have shown clinical effectiveness by reducing graft-versus-host disease and autoimmune reactions. They achieve this through mechanisms such as suppressing inflammatory T-cell activation, promoting regulatory T-cell expansion, and modulating macrophage polarization. Despite these advances, several challenges remain. One key concern is the potential tumorigenic risk caused by genomic instability during genome editing and long-term cell expansion. Emerging precision editing platforms, including base editing and prime editing, provide strategies to reduce double-strand DNA break-induced chromosomal rearrangements and improve genomic safety. Future research priorities include integrating AI-based immune profiling, precision genome editing, and advanced 3D-bioprinting technologies. Together, these innovations represent a paradigm shift toward developing safer, more effective, universally compatible stem cell therapies for diseases previously deemed untreatable.

Cancer stem cells represent a critical cell population that drives the malignant proliferation and invasiveness of glioblastoma (GBM), contributing to its poor prognosis. However, the mechanisms underlying the maintenance of stemness in GBM is poorly understood. In this study, we identified Rho guanine nucleotide exchange factor 26 (ARHGEF26) as a protein enriched in GBM stem cells and GBM tissues. High expression of ARHGEF26 was associated with shorter survival in patients with GBM. Functionally, ARHGEF26 enhanced the self-renewal, invasion, and tumorigenesis of GBM cells both in vitro and in vivo. Mechanistically, ARHGEF26 interacted with and stabilized the core stemness transcription factor SOX2 by reducing its K48-linked poly-ubiquitination and subsequent proteasomal degradation. Our findings reveal a novel role and mechanism for ARHGEF26 in promoting GBM stemness and suggest its potential as a therapeutic target.

Open tibial fractures with major bone loss, especially from high-energy trauma, are prone to atrophic nonunion, pseudoarthrosis, infection, and limb shortening. Standard methods like Ilizarov fixation often fail when healing is poor or infection persists, making adjunctive biological therapies necessary. Although the Ilizarov technique is established for tibial nonunion, evidence on mesenchymal stem cell (MSC)-rich bone marrow injections remains limited. We reported 2 young male patients with open tibial fractures and substantial bone loss. Both were initially managed with Ilizarov fixation for 7 - 8 months but subsequently developed atrophic nonunion, pseudoarthrosis, persistent infection with fistula, and limb shortening. Examination showed abnormal motion and absence of bone fragments, and labs confirmed ongoing infection. The definitive management involved a staged surgery, augmented by dual intraosseous injections of autologous MSC-rich bone marrow. This protocol successfully achieved bony union. The Ilizarov frame was then replaced with an AO fixator for consolidation. Both patients regained full limb length and infection resolution, with minor fibrotic tissue formation. Tibial pseudoarthrosis with infection and bone loss is challenging. In our cases, combining Ilizarov distraction with MSC-rich marrow enhanced osteogenesis, leading to union in a shorter time and full recovery. This synergy highlights the potential of regenerative strategies in complex orthopedic trauma.

The pituitary gland plays a central role in maintaining physiological homeostasis by secreting multiple hormones that regulate diverse body functions. Dysregulation of pituitary hormones can arise from various conditions, such as pituitary tumors and autoimmune diseases, leading to a broad spectrum of symptoms. During embryonic organogenesis, the pituitary gland originates from the oral ectoderm in close contact with the adjacent hypothalamus. This tissue interaction is essential for proper development. Although the molecular mechanisms underlying pituitary development and related disorders have been extensively studied using animal models, such as rodents and zebrafish, species-specific differences limit the translatability of these findings to humans. Moreover, the scarcity of established human pituitary cell lines has hindered the investigation of human-specific mechanisms. Recent biotechnological advances have addressed these limitations by enabling the long-term culture of human pituitary tumor tissues and in vitro generation of pituitary hormone-producing cells from human pluripotent stem cells. These emerging platforms provide powerful tools for deepening our understanding of pituitary biology and diseases. In this review, we summarize current in vitro experimental models derived from pituitary tissues and pluripotent stem cells and discussed their applications in the study of pituitary development, physiology, and related disorders.

Cell mechanics, elasticity and viscoelasticity, are key markers of biological states like cancer. Atomic force microscopy (AFM) is ideal for such studies, but its low throughput limits large-scale use. Two solutions exist: automation for higher throughput, or high-density measurements for richer data. The latter enables machine learning (ML)-based classification, with viscoelastic parameters offering unique insights beyond static measures like Young's modulus.

Previous studies have shown that the lung tissues of preterm infants with bronchopulmonary dysplasia (BPD) are infiltrated by pro-inflammatory macrophages. The Wnt5a/frizzled-5/CaMKII signaling pathway plays a critical role in regulating macrophage activation. The antimicrobial peptide LL37, an important paracrine factor secreted by cord blood mesenchymal stem cells, modulates macrophages. Lower LL37 levels are associated with a higher risk of BPD. However, whether LL37 protects against inflammation-induced lung injury and its underlying mechanisms remain unclear.

Bone marrow organoids (BMOs) are three-dimensional cell culture models that recapitulate key structural and functional features of the bone marrow (BM) niche. BMOs offer important advantages in hematopoietic research by modeling key aspects of human hematopoiesis compared to classical in vitro two- and three-dimensional cellular models including bioreactors, BM-on-a-chip platforms, 2D models or BM ossicles by better recreating the three-dimensional architecture, cellular heterogeneity, and spatial organization of the BM microenvironment. They offer a scalable and cost-effective alternative to animal models and reduce the need for animal experiments. Induced pluripotent stem cell (iPSC)-derived BMOs can be generated from a patient's own cells, enabling personalized disease modeling and drug testing and are highly amenable to gene editing technologies allowing precise modifications to study gene function or model diseases. Recent landmark studies from Christoph Klein and Abdullah Khan have established protocols for the generation of BMOs and demonstrated their applications in disease modeling. Here, we review the critical steps in BMO generation, their structural/ functional validation and discuss how BMOs can be applied to model inflammatory responses, rare genetic bone marrow failure syndromes, and multiple myeloma. These advances demonstrate BMOs' growing potential as powerful tools in hematopoietic research and will pave the way for further innovation and increasingly refined systems in future studies.

Dormant cancer stem cells (CSCs) are the root cause of the drug resistance and metastatic processes of malignant tumors, but an in-depth analysis of their biological mechanisms is needed. Dormant CSCs are in the G0 phase of the cell cycle and are characterized by enhanced autophagic activity, a stable genomic structure and strong plasticity. Recently, several new specific markers of dormant CSCs, such as p27, CD13, QSOX1, Survivin, GPD1 and BEX2, have been identified, which offer hope for targeted therapy. In addition, epigenetic modifications such as DNA methylation and histone modifications have been reported to regulate the transition between the quiescent and proliferative states of dormant CSCs. From a clinical perspective, keeping cancer stem cells in a dormant state is helpful for preventing tumor recurrence and metastasis. To this end, clarifying the potential mechanisms and molecular regulation of cancer stem cell dormancy is vital. Here, in this review, we examine recent significant findings regarding tumor stem cell dormancy in both experimental and human disease models, emphasizing the underlying molecular mechanisms, regulatory processes, experimental models, and prospective research directions aimed at advancing this field and enhancing clinical translation.

Homologous recombination (HR) is crucial for maintaining genomic integrity and is tightly regulated, yet the role of ubiquitin-dependent degradation in HR proteins remains poorly understood. Through high-throughput screening for compounds that modulate the DNA replication stress response, we identify ML367 and its derivative, UNI418. Kinase profiling and detail molecular analyses reveal that UNI418 inhibits PIKfyve and PIP5K1C, reducing inositol hexaphosphate (IP6) levels and triggering Cul4A-dependent degradation of RAD51, CtIP, and CHK1. Further analysis identifies WDR5 as a DCAF protein that facilitates Cul4A-mediated proteolysis of RAD51 and CHK1. Functionally, UNI418 suppresses HR, enhances tumor sensitivity to PARP inhibitors (PARPis), and re-sensitizes PARPi-resistant tumor cells in both in vitro and in vivo xenograft models. These findings reveal a Cul4A-WDR5-dependent proteolysis pathway regulating HR protein stability via phosphatidyl inositol signaling. This mechanism offers a promising therapeutic strategy for overcoming PARPi resistance and improving combinatorial cancer treatment strategies.

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy of T-cell precursors. Although the survival rates have improved with the use of intensive chemotherapy, the emergence of relapse as well as treatment-related morbidity and mortality remain major challenges. Novel treatment approaches include the inhibition of anti-apoptotic regulators or cellular immunotherapies. Here, we analyzed the sensitivity of T-ALL to inhibitors of BCL-2 (venetoclax), BCL-XL (A1331852), MCL-1 (AZD5991) and dual inhibition of BCL-2/BCL-XL (AZD4320) and evaluated their combination effects with natural killer (NK) cells. While only early T-cell precursor (ETP) ALL was sensitive to BCL-2 inhibition, MCL-1 inhibition alone was not effective in most cell lines and patient-derived xenograft (PDX) samples. For BCL-XL and dual BCL-2/BCL-XL inhibition, we observed heterogeneous sensitivities, which were associated with anti-apoptotic dependencies on the respective BCL-2 family members as assessed by BH3-profiling. Moreover, we identified functional shifts in anti-apoptotic dependencies upon exposure to AZD4320 or AZD5991 alone and synergistic effects when both inhibitors were combined with each other, allowing cell death induction in resistant samples. We then explored the potential use of apoptosis-inducing drugs as sensitizers for immunotherapy. Therefore, we investigated the potential of NK cell-mediated killing in T-ALL and found heterogeneous sensitivity, with some cell lines showing responses even at low effector-to-target (E:T) ratios. Importantly, NK cell-mediated killing could be further enhanced by combining NK cells with AZD4320, proposing this combination as a potential effective treatment. Taken together, we demonstrated promising potential of BH3-mimetics and NK cells for the treatment of T-ALL alone and in combination, warranting further preclinical and potential clinical evaluation.

Microplastics (MPs) are emerging pollutants that are associated with many diseases including atherosclerosis, inflammatory bowel disease (IBD), and Alzheimer's. The oral cavity is the primary point for the uptake of MPs by human, where MPs could pose risks to oral and even system health. Various polymer-based materials have been used as dental materials in oral treatment, however, the assessment of MPs in dental treatments remains limited and the processes and mechanisms by which MPs affect human health through the oral route are elusive. Here, we report the assessment of the risks and sources of MPs in dental clinics, the establishment of the relationship between MPs and oral inflammatory disorders, and also the elucidation of underlying mechanisms. Our results showed that commonly used therapeutic dental materials could generate MPs in dental clinics with proportions significantly higher than those in office areas and outdoors. As a representative, polymethyl methacrylate (PMMA) MPs showed significant toxicity to human oral keratinocytes (HOK), human periodontal ligament stem cells (hPDLCs), and THP-1-derived macrophages. Mechanistic investigations of apoptosis and inflammation processes revealed that MPs could lead to mitochondrial stress and autophagy and trigger the Notch signaling pathway and the JAK-STAT signaling pathway. Mice experiments showed that prolonged high-dose MPs exposure induced periodontal inflammatory reactions and even led to inflammatory bone resorption. This study provides a scientific basis for the oral health risks by MPs in dental practice and addresses the need for the development of dental materials with higher biocompatibility and environmentally sustainability.

Ameloblastoma is a benign odontogenic tumor with an aggressive growth phenotype orchestrated by a complex and heterogeneous tumor microenvironment. This review addresses how tumor cells, cancer-associated fibroblasts, mesenchymal stem cells, endothelial cells, and immune cells interact with non-cellular elements especially the extracellular matrix and hypoxic niches to drive invasive growth and recurrence. Several genetic changes associated with ameloblastoma activate mitogen-activated protein kinase (MAPK), Hedgehog (HH), Wnt/β-catenin, and less commonly PI3K/AKT signaling pathways. These pathways increase matrix-degrading enzymes such as matrix metalloproteinases and heparanase and reorganize collagen to create paths for local spread of ameloblastoma cells. Hypoxic niches in ameloblastoma stabilize hypoxia-inducible factor (HIF-1)α and activate vascular endothelial growth factor (VEGF) thereby linking low oxygen tension to new blood vessel growth within the microenvironment. Crosstalk between ameloblastoma epithelium and stroma through interleukin-6, transforming growth factor (TGF)-β, and connective tissue growth factor (CTGF) activates a positive feedback loops that stiffen the extracellular matrix and promote collective invasion. Within the encompassing jaw bone, a higher receptor activator of nuclear factor kappa-Β ligand/osteoprotegerin (RANKL/OPG) ratio and parathyroid hormone-related protein (PTHrP) level stimulate osteoclastogenesis, which accounts for the characteristic osteolysis displayed by ameloblastoma. Additionally, PD-L1 expression in ameloblastoma weakens T-cell activity in spite of the high population of M1 macrophages at the tumor leading edge. Collectively, coordinated interplay of these molecular processes define the invasive and aggressive growth phenotypes of ameloblastoma. Opportunities abound for development of targeted therapies for management of ameloblastoma. Potential candidates are inhibitors of BRAF/MEK and smoothened (SMO) gene/HH pathways, interruption of the TGF-β-Cancer-associated fibroblast axis, anti-angiogenic strategies, immune checkpoint blockade, and RANKL-directed therapy.

Background and objectives Atherosclerosis is a chronic disease marked by the build up of lipids and inflammatory cells in arterial walls, leading to vessel narrowing and increasing the risk of serious complications like heart attack and stroke. Recent findings suggest that microRNAs (miRNAs) serve as key regulators in the mechanisms driving atherosclerotic disease. However, the expression levels and functional roles of miRNA-133a-3p and miRNA-124-3p in atherosclerosis remain incompletely understood. The aim of this study was to determine the relationship between the expression levels of miR-124-3p and miR-133a-3p, and the phenotypic changes of S100A4-positive vascular smooth muscle cells in atherosclerosis. Methods We collected tissue samples from 25 patients with atherosclerosis who underwent coronary artery bypass graft surgery. IMA tissues were used as controls; atherosclerotic aortic tissues as cases. Expression levels of miRNAs were assessed using reverse transcription polymerase chain reaction (RT-PCR). Tissue samples underwent immunohistochemical staining with S100A4 protein to evaluate cellular and structural characteristics. Results A marked decrease in the expression of miR-133a-3p and miR-124-3p was observed in the atherosclerosis group compared to the control group, and both differences were statistically significant (P=0). Additionally, an increase in S100A4 protein immunoreactivity was detected in the atherosclerosis group. Interpretations and conclusions The downregulation of miRNA-133a-3p and miRNA-124-3p in atherosclerotic tissues, along with the observed increase in S100A4 protein immunoreactivity, suggests that these two miRNAs may play a role in the regulation of inflammatory endothelial phenotypes. Therefore, the interaction between miRNA-133a-3p, miRNA-124-3p, and S100A4 protein may help elucidate a potential mechanism underlying the prevention of atherosclerosis.

Mesenchymal stem cells (MSC) represent the main stromal component of the bone marrow (BM) niche and are crucial to maintain hematopoietic tissue homeostasis. MSC exhibits extraordinary and multiple properties. In terms of expanding potential and differentiation capacity, Wharton jelly MSC (WJ-MSC), derived from the umbilical cord, was described as being greater and more performing than MSC from BM or other sources. WJ-MSC mimics the hematopoietic niche and supports hematopoietic stem cells (HSC) expansion ex vivo. This study aimed to evaluate the effects of human WJ-MSC cocultured with HSC in a B-cell differentiation protocol. Remarkably, results highlight WJ-MSC use as a preferable feeder layer to efficiently support HSC commitment toward the B-lineage. Over 11 days of HSC coculture with WJ-MSC, B-cell genes (E2A, RAG1, RAG2, etc.) expression patterns and B-cell markers (CD19, immunoglobulin chain, etc.) acquisition were evidenced. WJ-MSc were also able to unlock the B-lineage differentiation blockade of the acute lymphoblastic leukemia cell line Nalm16. This model might provide a new strategy to support ex vivo B-cell differentiation using the powerful properties of WJ-MSC. This study implements a new approach to improve understanding of B-leukemogenesis and B-cell acute lymphoblastic leukemia (B-ALL) pathophysiology.

Transendothelial migration (TEM), is a complex, multistep process impacted by diseases like autoimmune disorders and cancer. Deciphering aspects of the process enhances our understanding and possibilities for disease treatments. The extent to which this potential can be leveraged is often limited due to conventional assays neither accurately mimicking specific in vivo conditions like sheer stress nor visualizing the whole transmigration cascade, hence missing distinct mechanisms. Flow-based adhesion assays overcome these limitations and allow the use of various endothelial cells from different tissues with distinct properties. So far, a broader and translational assay application is hampered by potential operator-based bias/lack of standardization, as well as poor scalability due to time-consuming manual analysis. In this study, we successfully combined this assay with AI-based analysis including subsequent classification of cell-transmigration phases by a Keras/TensorFlow-based deep learning model. Trained on healthy-donor and pancreatic cancer patient-derived T cells, the model achieved a high accuracy of 91.6 % in identifying/categorizing cell transmigration, surpassing the currently accepted 80 %-threshold, therefore qualifying as a fast, standardized AI-based live-cell imaging tool. Additionally, its architecture grants highly convenient reconfiguration for various disease-model investigations. Hence, by combining an affordable and simplistic, yet potent live-cell-imaging technique with a comprehensive AI-approach, we have established a powerful tool which allows for integrating TEM-assays into various disease models.

Melanocyte stem cells (McSCs) are a crucial melanocyte reservoir within the hair follicle niche. This review provides an overview of the processes for McSC quiescence and activation. Because McSCs closely interact with hair follicle stem cells, we have focused on this interaction. Given the high prevalence of hair graying, the McSC system serves as a model for cellular aging. Here, we highlight current research on the mechanisms of hair graying.

Iron metabolism is increasingly recognized as a key player in the development and progression of various cancers. Iron is required for vital cellular processes such as energy production; however, it can also interact with reactive oxygen species to cause cellular toxicity. Consequently, a host of proteins coordinate iron homeostasis, and ferritin stands out as a promising therapeutic target due to its pivotal role in buffering cellular iron levels. This review explores the relevance of ferritin in brain cancers, shedding light on how it influences the biology of both tumor cells and cancer stem cells (CSCs), a population of tumor cells that is notable in their resistance to conventional treatment strategies. Ferritin plays a critical role in protecting against oxidative stress and boosting resistance to ferroptosis, a form of cell death often evaded by CSCs. Development of cutting-edge strategies designed to target ferritin, including ferritinophagy-inducing compounds and novel redox-based therapies that can capitalize on the iron dependency of CSCs is discussed in context. We propose that the iron addiction of brain cancer cells provides a specific susceptibility, whereby removing their iron buffering mechanism via targeting of ferritin can result in favorable treatment outcomes, including the induction of iron-dependent cell death. Future studies on the modulation of ferritin offer a ground-breaking therapeutic strategy to undermine CSC-driven tumor growth, overcome resistance to conventional therapies, and ultimately improve treatment outcomes for patients battling brain cancers.

Dental tissues development involves two distinct cell lineages: mesenchymal cells (derived from the cranial neural crest) and epithelial cells (derived from oral ectoderm and pharyngeal epithelium). Emerging evidence highlights the remarkable functional heterogeneity of cranial neural crest-derived dental mesenchymal stem cells (DMSCs), exhibiting pluripotency, self-renewal, and differentiation capacities. This heterogeneity enables a single DMSC population to generate specialized subpopulations with unique roles in teeth and periodontal tissues formation. Significant progress has been made in characterizing six major types of DMSCs and two populations of closely related cells: Tooth germ progenitor cells (TGPCs) and dental follicle stem cells (DFSCs), critical during early morphogenesis; Stem cells from human exfoliated deciduous teeth (SHEDs) and apical papilla stem cells (SCAPs), pivotal for root development; Dental pulp stem cells (DPSCs), periodontal ligament stem cells (PDLSCs), gingival mesenchymal stem cells (GMSCs) and alveolar bone mesenchymal stem cells (ABMSCs), essential for maintaining and regenerating mature dental tissues. A key breakthrough has unveiled the development and hierarchy of DMSCs by applying new techniques like single-cell RNA sequencing (scRNA-seq). To integrate insights into the development of teeth and periodontal tissues, this review synthesizes current knowledge on both developmental heterogeneity and subpopulation heterogeneity within DMSCs and related cells. These insights not only advance fundamental understanding of the developmental mechanisms of teeth and periodontal tissues, but also establish a promising framework for achieving more efficient tissue regeneration and repair engineering.