This review article examines how stem cell therapies can cure various diseases and injuries while also discussing the difficulties and moral conundrums that come with their application. The article focuses on the revolutionary developments in stem cell research, especially the introduction of gene editing tools like CRISPR-Cas9, which can potentially improve the safety and effectiveness of stem cell-based treatments. To guarantee the responsible use of stem cells in clinical applications, it is also argued that standardizing clinical procedures and fortifying ethical and regulatory frameworks are essential first steps. The assessment also highlights the substantial obstacles that still need to be addressed, such as the moral dilemmas raised by the use of embryonic stem cells, the dangers of unlicensed stem cell clinics, and the difficulties in obtaining and paying for care for patients. The study emphasizes how critical it is to address these problems to stop exploitation, guarantee patient safety, and increase the accessibility of stem cell therapy. The review also addresses the significance of thorough clinical trials, public education, and policy development to guarantee that stem cell research may fulfill its full potential. The review concludes by describing stem cell research as a promising but complicated topic that necessitates a thorough evaluation of both the hazards and the benefits. To overcome the ethical, legal, and accessibility obstacles and eventually guarantee that stem cell treatments may be safely and fairly included in conventional healthcare, it urges cooperation between the scientific community, legislators, and the general public.

Spinal cord injury (SCI) results in chronic motor deficits and intractable neuropathic pain, driven by neuroinflammation and impaired tissue repair. Current therapies inadequately address these multifaceted challenges. This study investigated the therapeutic effects of human adipose-derived mesenchymal stem cells (hADSCs) transplantation combined with green light (GL) therapy to modulate inflammation, enhance autophagy, and facilitate functional restoration post-SCI.

Neurological disorders, ranging from common conditions like Alzheimer's disease that is a progressive neurodegenerative disorder and remains the most common cause of dementia worldwide to rare disorders such as Angelman syndrome, impose a significant global health burden. Altered facial expressions are a common symptom across these disorders, potentially serving as a diagnostic indicator. Deep learning algorithms, especially convolutional neural networks (CNNs), have shown promise in detecting these facial expression changes, aiding in diagnosing and monitoring neurological conditions.

The tumor microenvironment (TME) plays a pivotal role in cancer progression, with cancer-associated fibroblasts (CAFs) significantly influencing tumor behavior. Especially, elevated COX2 expressing fibroblasts within the TME, notably in collagen-dense tumors like breast cancer, has been recently emphasized in the literature. However, the specific effect of COX2-expressing CAFs (COX2+ CAFs) on neighboring cells and their consequent role in cancer progression is not fully elucidated.

The results of this research contribute to the LifeSaver project, which focuses on reducing neonatal and infant mortality resulting from preterm births. The project aims to create an in vitro system simulating prenatal conditions to screen and analyze chemicals and pharmaceuticals, establishing scientifically justified regulations for their use during pregnancy. Because several papers have recently identified data inconsistencies in pre-clinical studies, a key part of the project involves optimizing cellular cytotoxicity assays to enhance the reliability of pharmacological and toxicity screening for drugs and environmental contaminants.

Chronic back pain and disability are primarily caused by intervertebral disc degeneration (IDD) that requires novel therapies to regenerate the nucleus pulposus (NP) and restore disc function. In this study, a bioengineered thermo-sensitive injectable hydrogel composed of co-polymeric poly-N-isopropyl acrylamide-grafted-chondroitin sulfate cross-linked with sodium alginate microspheres (PNIA-g-CS-NaA Ms: denote HMs) loaded with growth differentiation factor 5 (GDF-5), to stimulate Nucleus Pulposus cells (NPCs) activity and promote intervertebral disc (IVD) regeneration. The Low critical solution temperature (LCST) of PNIA-g-CS was 31.8 and 32.3 °C at 5% (w/v) and 15% (w/v), respectively. In the in vitro study, GDF-5-loaded hydrogel (1 mg/mL) marginally enhanced NPC proliferation and reduced inflammatory cytokines (TNF-α, IL-6, IL-1β) after 24 h. HMs-GDF-5 combined with Adipose-Derived Mesenchymal Stem Cells (ADMSCs) was delivered to NP tissue using a minimally invasive technique, promoting NP regeneration in rats. At 8 weeks, significant upregulation of COL-II and ACAN proteins and mRNA expressions was observed. X-ray imaging showed disc height recovery and increased water content, while histology revealed partial restoration of NPCs and matrix. The outcomes show that the biodegradable hydrogel could be used as a potential therapeutic agent for IVD repair.

Glioblastoma (GBM) is a highly resistant tumor, and targeting its bioenergetics could be a potential treatment strategy. GBM cells depend on cytosolic nicotinamide adenine dinucleotide (NADH), which is transported into the mitochondria via the malate-aspartate shuttle (MAS) for ATP production. N-phenylmaleimide (KN612) is a MAS inhibitor that targets SLC25A11, an antiporter protein of the MAS. Therefore, this study investigated the effects of KN612 in GBM treatment using in vitro and in vivo models.

Targeted radionuclide therapy against cancer stem cell-specific markers, such as CD133, constitutes a promising strategy to eliminate resilient cancer stem cells for improved outcomes in refractory tumors. Here, we report the synthesis and evaluation of [177Lu]Lu-DOTA-RW03, a CD133-targeted radioimmunotherapy.

When two lymphomas occur concurrently or sequentially in a patient, it is a major question whether they derive from the same lymphocyte or hematopoietic precursor cell or developed independently. We studied four composite classic Hodgkin lymphomas (HL) and other mature B-cell lymphomas, and two composite mature B- and T-cell neoplasias by whole exome sequencing (WES). Analysis of their IGV genes revealed that three composite B-cell lymphomas originated from common germinal center-experienced B cells. WES identified shared somatic mutations in the lymphomas of these clonally related composite lymphomas, indicating their derivation from a common, pre-malignant precursor. Most mutations were restricted to one or the other of these lymphomas, likely explaining how distinct lymphomas developed from a common ancestral B cell. In the two B-cell/T-cell lymphoma cases, and a composite clonally unrelated HL/chronic lymphocytic leukemia, the lymphoma partners did not share any somatic mutations. In three cases, we identified potentially oncogenic variants also in cells serving as constitutional controls. These variants may have contributed to development of a composite lymphoma/leukemia. We provide additional evidence of frequent clonal relation in composite lymphomas, highlight the multistep transformation process of related lymphomas with a likely pre-malignant intermediate common precursor, and support the importance of constitutional variants in lymphomagenesis.

Acute myeloid leukemia (AML) is a common hematopoietic malignancy with high recurrence rates, and there is an urgent need for new therapeutic agents. T-cell immunoglobulin mucin-3 (TIM-3) is expressed on the surface of both LSCs and blasts in most AML patients, but not in normal hematopoietic stem cells (HSCs). We have developed KK2845, an antibody drug conjugate (ADC) that consists of an anti-TIM-3 fully human IgG1 antibody, a valine-alanine linker and a highly potent DNA cross-linking pyrrolobenzodiazepine (PBD) dimer SG3199. KK2845 exhibited potent cytotoxicity against AML cells both in vitro and in vivo. The cytotoxicity against AML cells was almost comparable between KK2845 and CD33-ADC, an anti-CD33 antibody conjugated with PBD dimer that has shown high remission rates in clinical studies. In addition to the cytotoxicity depending on PBD dimer, KK2845 also showed potent antibody-dependent cell cytotoxicity (ADCC) activity against AML cells. KK2845 showed less cytotoxicity against human normal bone marrow cells than CD33-ADC. The pharmacokinetics of KK2845 in cynomolgus monkey after intravenous infusion demonstrated a favorable profile. Taken together, these data suggest that KK2845 could be a novel ADC therapeutic in AML.

The modulation of microglial reactivity has emerged as a potential target for developing ischemic stroke therapies. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) possess immunomodulatory properties that may influence microglial responses following ischemia. However, individual studies assessing this influence have provided limited results. Therefore, we conducted a systematic review and meta-analysis to investigate whether MSC-EVs treatment alters microglial responses in animal and cellular models of ischemic stroke. In accordance with the PRISMA 2020 statement, we searched PubMed, Web of Science, and EMBASE until October 2023 for studies assessing cellular and molecular parameters of microglial reactivity following MSC-EVs treatment in models of ischemic stroke. We estimated treatment effects using a random-effects meta-analysis of standardized mean differences and estimated heterogeneity via the I2 statistic. The risk of bias was assessed using the SYRCLE questionnaire. The search identified 297 studies, 27 of which met the inclusion criteria. In animal models, MSC-EVs reduced the number, surface area, and fluorescence intensity of Iba1+ cells, as well as the number of Iba1+ cells co-expressing the pro-inflammatory markers CD16, CD32, CD85, and iNOS. Conversely, MSC-EVs increased the number of Iba1+ cells co-expressing the anti-inflammatory markers Arg-1 and CD206. In cellular models, we observed decreased concentrations of TNF-α, IL-1β, and IL-6 in the culture medium. Our meta-analysis consolidates the immunomodulatory effects of MSC-EVs on microglial responses to ischemia, underscoring the potential of microglia-specific therapeutics in the development of MSC-EVs-based and regenerative treatments for ischemic stroke.

The precise location and functions of N6-methyladenosine (m6A) modification on mammalian nuclear noncoding RNA remain largely unknown. Here we developed nuclear-m6A-label-seq to directly map human and mouse cell nuclear RNA m6A methylome at single-base resolution. Specifically, m6A modifications have been identified on abundant human γ satellite DNA II (GSATII) RNA transcripts, a type of repeat RNA, transcribed from SST1-TAR1-GSATII satellite arrays in the pericentromeric region of chromosome 9. GSATII RNA m6A positively regulates the transcription of GSATII-located satellite arrays as well as trans-associated peri/centromeric satellites, typically chromosome 3 centromeric higher-order repeat α satellite. Dysregulation of this circuit renders a phenotype of abnormal chromosome segregation. Mechanistic study reveals that YTHDC1 reads GSATII RNA m6A marks and recruits bromodomain protein 4 (BRD4) to promote transcriptions of the associated satellites via an m6A-YTHDC1-BRD4-H3K27ac axis. These results uncover a mechanism governing the transcription of cis- and trans-associated pericentromeric and centromeric satellites via cross-talk between epitranscriptomic and epigenomic marks.

Bone defects are common orthopedic conditions, and due to the limited regenerative capacity of bone tissue, their repair remains a challenge in orthopedic surgery. Mesenchymal stem cells (MSCs) have demonstrated strong potential for osteogenic differentiation; however, their efficiency in vivo remains restricted, particularly in terms of differentiation and migration. Photobiomodulation (PBM), a non-invasive therapeutic technique, has shown great promise in promoting stem cell differentiation. In this study, we cultured human umbilical cord mesenchymal stem cells (hUCMSCs) in vitro and treated them with 635/808 nm laser light. We measured alkaline phosphatase (ALP) activity, mineralized nodule formation, and the expression of osteogenesis-related genes and factors after 7, 14, and 21 days. The results showed that PBM treatment significantly enhanced hUCMSC proliferation and osteogenic differentiation. The mechanism behind this effect involves PBM activating the upstream Akt signaling pathway, increasing P-Akt expression, and elevating reactive oxygen species (ROS) levels to induce mild oxidative stress. This process enhances ALP activity, mineralized nodule formation, and the expression of osteogenesis-related genes and factors, thus promoting the osteogenic differentiation of hUCMSCs.

DNA polymerase γ (POLγ), responsible for mitochondrial DNA replication, consists of a catalytic POLγA subunit and two accessory POLγB subunits. Mutations in POLG, which encodes POLγA, lead to various mitochondrial diseases. We investigated the most common POLG mutations (A467T, W748S, G848S, Y955C) by characterizing human and mouse POLγ variants. Our data reveal that these mutations significantly impair POLγ activities, with mouse variants exhibiting milder defects. Cryogenic electron microscopy highlighted structural differences between human and mouse POLγ, particularly in the POLγB subunit, which may explain the higher activity of mouse POLγ and the reduced severity of mutations in mice. We further generated a panel of mouse models mirroring common human POLG mutations, providing crucial insights into the pathogenesis of POLG-related disorders and establishing robust models for therapeutic development. Our findings emphasize the importance of POLγB in modulating the severity of POLG mutations.

Stem cell-derived islet cell therapy can effectively treat type 1 diabetes, but its efficacy is hindered by low oxygen supply post-transplantation, particularly in subcutaneous spaces and encapsulation devices, leading to cell dysfunction. The response to hypoxia and effective strategies to alleviate its detrimental effects remain poorly understood. Here, we show that β cells within stem cell-derived islets gradually undergo a decline in cell identity and metabolic function in hypoxia. This is linked to reduced expression of immediate early genes (EGR1, FOS, and JUN), which downregulates key β cell transcription factors. We further identified genes important for maintaining β cell fitness in hypoxia, with EDN3 as a potent player. Elevated EDN3 expression preserves β cell identity and function in hypoxia by modulating genes involved in β cell maturation, glucose sensing and regulation. These insights improve the understanding of hypoxia's impact on stem cell-derived islets, offering a potential intervention for clinical applications.

Sodium benzoate (NaB) is a commonly used food ingredient that is also found in cosmetics and medicines. Previous studies have demonstrated that long-term NaB intake has detrimental effects on human health, while its effects on bone mass remain unknown. In the present study, intragastric NaB administration was found to decrease bone mass and deteriorate bone microstructure in vivo, while prolonged NaB gavage further accelerated bone loss. The in vitro study revealed that NaB inhibited osteoblast differentiation of bone marrow mesenchymal stem cells and MC3T3-E1 cells. Mechanistically, RNA sequencing analysis elucidated that NaB greatly suppressed fibroblast growth factor 2 (FGF2) expression. Further studies revealed that NaB inhibited p38/RUNX2 signaling transduction, which was downstream of FGF2 for modulating osteoblast differentiation. The rescue studies suggested that NaB inhibited RUNX2 expression and osteoblast differentiation through the p38/MAPK signaling pathway. Collectively, NaB accelerated bone loss by inhibiting osteoblast differentiation through downregulating FGF2/p38/RUNX2 signaling pathway. The present study revealed that the long-term intake of NaB-containing food increased the risk of bone loss and osteoporosis (OP). Therefore, a reasonable oral intake of NaB-containing food is an important but convenient initiative for preventing OP.

The remarkable cell diversity of multicellular organisms relies on the ability of multipotent progenitor cells to generate distinct cell types at the right times and locations during embryogenesis. A key question is how progenitors establish competence to respond to the different environmental signals required to produce specific cell types at critical developmental time points. We addressed this in the mouse developing forebrain, where neural progenitor cells must switch from producing neurons to making oligodendrocytes in response to increased Sonic hedgehog (SHH) signaling during late embryogenesis. We show that progenitor responses to SHH are regulated by Notch signaling, thus permitting proper timing of the neuron-oligodendrocyte switch. Notch activity epigenetically primes genes associated with the oligodendrocyte lineage and SHH pathway, enabling amplified transcriptional responses to endogenous SHH and robust oligodendrogenesis. These results reveal a critical role for Notch in facilitating progenitor competence states and influencing cell fate transitions at the epigenetic level.

Friedreich ataxia (FA) is an autosomal recessive disease characterized by progressive damage to the nervous system and severe cardiac abnormalities. The disease is caused by a GAA•TTC triplet repeat expansion in the first intron of the FXN gene, which results in epigenetic repression of FXN transcription and reduction in FXN (frataxin) protein which results in mitochondrial dysfunction. Factors and pathways that promote FXN repression represent potential therapeutic targets whose inhibition would restore FXN transcription and frataxin protein levels. Here, we performed a candidate-based RNAi screen to identify kinases, a highly druggable class of proteins, that when knocked down upregulate FXN expression. Using this approach, we identified Rho kinase ROCK1 as a critical factor required for FXN repression. ShRNA-mediated knockdown of ROCK1, or the related kinase ROCK2, increases FXN mRNA and frataxin protein levels in FA patient-derived induced pluripotent stem cells (iPSCs) and differentiated neurons and cardiomyocytes to levels observed in normal cells. We demonstrate that small molecule ROCK inhibitors, including the FDA-approved drug belumosudil and fasudil, reactivate FXN expression in cultured FA iPSCs, neurons, cardiomyocytes, and FA patient primary fibroblasts, and ameliorate the characteristic mitochondrial defects in these cell types. Remarkably, treatment of transgenic FA mice of both sexes with belumosudil or fasudil upregulates FXN expression, ameliorates the mitochondrial defects in the brain and heart tissues, and improves motor coordination and muscle strength. Collectively, our study identifies ROCK kinases as critical repressors of FXN expression and provides preclinical evidence that FDA approved ROCK inhibitors may be repurposed for treatment of FA.Significance Statement Friedreich ataxia is a debilitating disorder caused by epigenetic repression of the frataxin (FXN) gene, leading to neurodegeneration and cardiomyopathy. Through an RNA interference screen, we identified ROCK1 and ROCK2 kinases as critical repressors of FXN expression, making them promising therapeutic targets for upregulating FXN in patient-derived cells. Treatment with small-molecule ROCK inhibitors, including the FDA-approved drug belumosudil and clinically advanced fasudil, restores frataxin levels, alleviates mitochondrial defects, and improves disease phenotypes in cells and animal models. These findings establish ROCK kinases as targets for Friedreich ataxia therapy and open new avenues for repurposing existing ROCK inhibitors, warranting clinical exploration.