Activation of Wnt/β-catenin signalling via GSK3 inhibitors direct differentiation of human adipose stem cells into functional hepatocytes

Liposome-Polymer Nanoparticles Loaded with Copper Diethyldithiocarbamate and 6-Bromo-Indirubin-3'-Oxime Enable the Treatment of Refractive Melanoma

Despite significant advances in cancer immunotherapy, many patients fail to respond to current treatments, outlining the need to develop novel therapeutic modalities. Therapeutic resistance in cancer cells is mediated by significant genomic instability due to their oncogenic transformation and evolutionary pressures inside the tumor microenvironment (TME). However, these cellular and molecular adaptations can result in a significant increase in the baseline endoplasmic reticulum (ER) stress in TME-resident cells. This can be taken advantage of as a therapeutic strategy by using the metal chelate copper diethyldithiocarbamate (CuET), a potent inhibitor of the p97-UFD1-NPL4 protein complex to induce cytotoxicity and exacerbate ER stress in cancer cells. Here, CuET is combined with the anti-inflammatory drug 6-bromo-indirubin-3'-oxime (BIO), a potent GSK3 inhibitor, to modulate the aberrant inflammatory response inside the TME. However, both CuET and BIO are highly hydrophobic and exhibit poor bioavailability, requiring the development of an appropriate carrier. Herein, it is demonstrated that CuET and BIO can be efficiently loaded into liposomes that are stabilized by poly(vinylpyrrolidone). The liposome-loaded drug combination resulted in a significant decrease of 47% and 76% in the tumor burden of syngeneic B16F10 and YUMM1.7 mouse models, respectively, without any major acute toxicity.

UPS and Kinases-Gatekeepers of the G1/S Transition

The G1/S transition is a highly regulated and pivotal checkpoint in the cell cycle, where the cell decides whether to commit to DNA replication and subsequent division or enter a non-dividing state. This checkpoint serves as a critical control point for preventing uncontrolled cell proliferation and maintaining genomic stability. The major driving force underlying the G1/S transition is the sequential activation of Cyclin-dependent kinases (CDKs), which is regulated by the coordinated binding of Cyclin partners, as well as the phosphorylation and ubiquitin-mediated degradation of both Cyclin partners and Cyclin-dependent kinase inhibitors (CKIs). Various E3 ligase families govern the timely degradation of these regulatory proteins, with their activity intricately controlled by phosphorylation events. This coordination enables the cells to efficiently translate the environmental cues and molecular signaling inputs to determine their fate. We explore the evolution of three distinct models describing the G1/S transition, highlighting how the traditional linear model is being challenged by recent paradigm shifts and conflicting findings. These advances reveal emerging complexity and unresolved questions in the field, particularly regarding how the latest insights into coordinated phosphorylation and ubiquitination-dependent degradation integrate into contemporary models of the G1/S transition.

Influencing hair regrowth with EGCG by targeting glycogen synthase kinase-3β activity: a molecular dynamics study

Hair follicle growth process through several well-organized stages with specific input by several signaling pathways including Wnt/β-catenin and Sonic Hedgehog with GSK3β in this process. As such, this research focus on investigating the efficacy of molecules that are able to inhibit GSK3β action in inducing hair regrowth. Applying computational techniques, three compounds NMN, Resveratrol and EGCG were analyzed for their GSK3β inhibition. It was established that EGCG has the highest values of molecular docking scores and, in the case of the stability criteria such as RMSD and RMSF, presented the most stable dynamic simulation. EGCG has shown considerable TEMPORAL STABILITY with GSK3β in the complex, because over a period of 200 nanoseconds the molecules remained bound through hydrogen bonds and hydrophobic contacts. As confirmed by PCA, the largest conformational changes in GSK3β suggest significant inhibitory interaction. Out of all the studied compounds, EGCG turns out to be the most potent GSK3β inhibitor for hair regrowth purposes. The result obtained from the molecular dynamics simulation indicates that EGCG might exert a favorable impact to extract signaling pathways related with hair follicle cycling which is a significant objective. These outcome sets the phase for further experimental testing to discover the potential of EGCG in the treatment of alopecia.

Bioactive Carbon Dots from Clove Residue: Synthesis, Characterization, and Osteogenic Properties

Background/Objectives: Bone regeneration using nanomaterial-based approaches shows promise for treating critical bone defects. However, developing sustainable and cost-effective therapeutic materials remains challenging. This study investigates the osteogenic potential of clove-derived carbon dots (C-CDs) for bone regeneration applications. Methods: C-CDs were synthesized using a green hydrothermal method. The osteogenic potential was evaluated in human bone marrow-derived mesenchymal stem cells (hBM-MSCs) and validated using ectopic bone formation and calvarial defect models. Results: C-CDs demonstrated uniform morphology (~10 nm) with efficient cellular uptake. In vitro studies showed successful osteogenic differentiation through the upregulation of RUNX2, ALP, COL1A1, and BMP-2 mediated by Wnt/β-catenin/GSK3β and BMP signaling pathways. In vivo models have also demonstrated that C-CDs are effective in promoting bone regeneration. Conclusions: These findings establish C-CDs as promising candidates for bone regeneration therapy, offering a sustainable alternative to current treatments. While optimization is needed, their demonstrated osteogenic properties warrant further development for regenerative medicine applications.

Dissecting the novel molecular interactions of solute carrier family 4 member 4 (SLC4A4) for prostate cancer (PCa) progression

Prostate cancer (PCa) is the most common malignancy diagnosed in men. The purpose of this study was to report the molecular pathways of Homo sapiens solute carrier family 4 member 4 (SLC4A4) in the progression of PCa. Here, we report our findings from clinical specimens of prostatic acinar adenocarcinoma collected from patients. We found that low-grade prostate cancers have higher SLC4A4 expression. We investigated the role of SLC4A4 and the signaling mechanism underlying its role in modulating the PCa progression. Firstly, we reported the SLC4A4/GSK-3β/β-catenin signaling axis, which regulates the clonogenic potential, invasiveness, and metastasis. In this, we found reduced phosphorylation of GSK at serine 21 of α and serine 9 of the β subunit in shSLC4A4 cells of PCa, which ultimately relieved the activity of GSK-3β. This activated GSK-3β phosphorylates β-catenin at Ser33/37 with a subsequently reduced β-catenin level in PCa cells. Our functional analysis revealed that SLC4A4 knockdown retards tumor growth and lowers invasion and migration potential. Secondly, we investigated the SLC4A4/RB axis, which acts to drive cell proliferation. SLC4A4 knockdown decreases the interaction between these molecules with hypophosphorylation of RB protein and cell cycle arrest. Likewise, transcriptome sequencing using the SLC4A4 knockdown in DU145 cells regulates differentiated expressed genes and multiple metabolic pathways. Our results suggest that SLC4A4 may serve as a potential therapeutic target for prostate cancer patients in the future.

GSK3 inhibition improves skeletal muscle function and whole-body metabolism in male mouse models of Duchenne muscular dystrophy

Inhibiting glycogen synthase kinase 3 (GSK3) improves muscle function, metabolism, and bone health in many diseases and conditions; however, whether GSK3 should be targeted for Duchenne muscular dystrophy (DMD), a severe muscle wasting disorder with no cure, remains unknown. Here, we show the effects of GSK3 inhibition in male DBA/2J (D2) and C57BL/10 (C57) mdx mice. Treating D2 mdx mice with GSK3 inhibitors alone or in combination with aerobic exercise improves muscle strength, endurance, and morphology, attenuates the hypermetabolic phenotype, and enhances insulin sensitivity. GSK3 inhibition in C57 mdx mice also improves muscle fatigue resistance and increases cage ambulation. Moreover, muscle-specific GSK3 knockdown in mdx mice augments muscle force production and endurance. In both mdx strains, GSK3 inhibition increases bone mineral content and density. Overall, these improvements to muscle, metabolic, and bone health with GSK3 inhibition in mdx mice may have clinical implications for patients with DMD, where the current standard of care, glucocorticoids, delay the loss of ambulation but increase the risk for insulin resistance and osteoporosis. Along with our observation of lowered β-catenin content in DMD myoblasts, a known cellular target for GSK3, this study provides ample evidence in support of inhibiting GSK3 for this disease.

Innovative pathological network-based multitarget approaches for Alzheimer's disease treatment

Alzheimer's disease (AD) is the most prevalent neurodegenerative disease and is a major health threat globally. Its prevalence is forecasted to exponentially increase during the next 30 years due to the global aging population. Currently, approved drugs are merely symptomatic, being ineffective in delaying or blocking the relentless disease advance. Intensive AD research describes this disease as a highly complex multifactorial disease. Disclosure of novel pathological pathways and their interconnections has had a major impact on medicinal chemistry drug development for AD over the last two decades. The complex network of pathological events involved in the onset of the disease has prompted the development of multitarget drugs. These chemical entities combine pharmacological activities toward two or more drug targets of interest. These multitarget-directed ligands are proposed to modify different nodes in the pathological network aiming to delay or even stop disease progression. Here, we review the multitarget drug development strategy for AD during the last decade.

Molecular Docking, Bioinformatic Analysis, and Experimental Verification for the Effect of Naringin on ADHD: Possible Inhibition of GSK-3β and HSP90

Background/Objectives: One of the most abundant and growing neurodevelopmental disorders in recent decades is attention deficit hyperactivity disorder (ADHD). Many trials have been performed on using drugs for the improvement of ADHD signs. This study aimed to detect the possible interaction of naringin with Wnt/β-catenin signaling and its putative anti-inflammatory and protective effects in the mouse ADHD model based on bioinformatic, behavioral, and molecular investigations. Furthermore, molecular docking was applied to investigate possible interactions with the GSK-3β and HSP90 proteins. Methods: Male Swiss albino mice were divided into four groups, a normal control group, monosodium glutamate (SGL) control, SGL + naringin 50 mg/kg, and SGL + naringin 100 mg/kg. The psychomotor activity of the mice was assessed using the self-grooming test, rope crawling test, and attentional set-shifting task (ASST). In addition, biochemical analyses were performed using brain samples. Results: The results of the SGL group showed prolonged grooming time (2.47-folds), a lower percentage of mice with successful crawling on the rope (only 16.6%), and a higher number of trials for compound discrimination testing in the ASST (12.83 ± 2.04 trials versus 5.5 ± 1.88 trials in the normal group). Treatment with naringin (50 or 100 mg per kg) produced significant shortening in the grooming time (31% and 27% reductions), as well as a higher percentage of mice succeeding in crawling with the rope (50% and 83%, respectively). Moreover, the ELISA assays indicated decreased dopamine levels (0.36-fold) and increased TNF-α (2.85-fold) in the SGL control group compared to the normal mice, but an improvement in dopamine level was observed in the naringin (50 or 100 mg per kg)-treated groups (1.58-fold and 1.97-fold). Similarly, the PCR test showed significant declines in the expression of the Wnt (0.36), and β-catenin (0.33) genes, but increased caspase-3 (3.54-fold) and BAX (5.36-fold) genes in the SGL group; all these parameters were improved in the naringin 50 or 100 mg/kg groups. Furthermore, molecular docking indicated possible inhibition for HSP90 and GSK-3β. Conclusions: Overall, we can conclude that naringin is a promising agent for alleviating ADHD symptoms, and further investigations are required to elucidate its mechanism of action.

Hyaluronic acid-alginate hydrogel stimulates the differentiation of neonatal mouse testicular cells into hepatocyte-like and other cell lineages in three-dimensional culture

BACKGROUND INFORMATION

Extracellular matrix (ECM)-derived hydrogels are frequently used in three-dimensional (3D) cell culture and organoid formation in several tissues. However, in the 3D cultivation of testicular cells, the hyaluronic acid (HA) hydrogel has not received as much attention. This study examined the effects of three distinct composites, including HA-alginate (HA-Alg), HA-alginate-collagen (HA-Alg-Col), and HA-alginate-decellularized ECM (HA-Alg-dECM), on mouse testicular cell culture and in vitro spermatogenesis.

METHODS

For the creation of composites, the concentration of biomaterials used was 0.5% HA, 1% alginate, 2.5 mg/mL collagen, and 25 mg/mL dECM derived from the testicles of Rams. After 3D culture of 5 days post-partum (dpp) mouse testicular cells for 14 days, HA-Alg was selected as a superior composite due to the greater number and size of the produced organoids. Then, cell culture was rerun by HA-Alg for 14 days, which was later extended for an additional 28 days. In addition, the 3D culture of 10 dpp mouse testicular cells was used to compare with 5 dpp mice on day 14. The morphology and gene expression were analyzed using appropriate techniques.

RESULTS

On day 14, the HA-Alg hydrogel showed significantly more organoids in terms of size and number than the other two groups (p < 0.05); nevertheless, none of the groups showed the expected signs of testis organoids. Remarkably, on day 14, the histology and immunostaining tests revealed features of hepatocyte-like cells (HLCs) and albumin production as a marker of HLC functionality. Furthermore, the analysis of gene expression verified the significant expression of angiogenesis markers (p < 0.01). After the extended culture to 28 days, 5 dpp testicular cells once more differentiated into erythrocytes and HLCs, while a small number of organoids showed the characteristic of renal cells. Cell culture of 10 dpp mice for 14 days showed a wide range of cell lineages, including renal, glandular, chondrocyte, and hepatocyte-like cells in comparison to the 5 dpp mice.

CONCLUSION AND SIGNIFICANCE

While the HA-Alg composite did not support spermatogenesis in the 3D culture of mouse testicular cells, it demonstrated an unpredicted potential for promoting the differentiation of neonate mouse testicular cells into HLC, erythrocytes, and other cell lineages.

Dipeptidyl peptidase-4 marks distinct subtypes of human adipose stromal/stem cells with different hepatocyte differentiation and immunoregulatory properties

BACKGROUND

Human adipose-derived stromal/stem cells (hASCs) play important roles in regenerative medicine and numerous inflammatory diseases. However, their cellular heterogeneity limits the effectiveness of treatment. Understanding the distinct subtypes of hASCs and their phenotypic implications will enable the selection of appropriate subpopulations for targeted approaches in regenerative medicine or inflammatory diseases.

METHODS

hASC subtypes expressing dipeptidyl peptidase-4 (DPP4) were identified via fluorescence-activated cell sorting (FACS) analysis. DPP4 expression was knocked down in DPP4+ hASCs via DPP4 siRNA. The capacity for proliferation, hepatocyte differentiation, inflammatory factor secretion and T-cell functionality regulation of hASCs from DPP4-, DPP4+, and control siRNA-treated DPP4+ hASCs and DPP4 siRNA-treated DPP4+ hASCs were assessed.

RESULTS

DPP4+ hASCs and control siRNA-treated DPP4+ hASCs presented a lower proliferative capacity but greater hepatocyte differentiation capacity than DPP4- hASCs and DPP4 siRNA-treated DPP4+ hASCs. Both DPP4+ hASCs and DPP4- hASCs secreted high levels of vascular endothelial growth factor-A (VEGF-A), monocyte chemoattractant protein-1 (MCP-1), and interleukin 6 (IL-6), whereas the levels of other factors, including matrix metalloproteinase (MMP)-1, eotaxin-3, fractalkine (FKN, CX3CL1), growth-related oncogene-alpha (GRO-alpha, CXCL1), monokine induced by interferon-gamma (MIG), macrophage inflammatory protein (MIP)-1beta, and macrophage colony-stimulating factor (M-CSF), were significantly greater in the supernatants of DPP4+ hASCs than in those of DPP4- hASCs. Exposure to hASC subtypes and their conditioned media triggered changes in the secreted cytokine profiles of T cells from healthy donors. The percentage of functional T cells that secreted factors such as MIP-1beta and IL-8 increased when these cells were cocultured with DPP4+ hASCs. The percentage of polyfunctional CD8+ T cells that secreted multiple factors, such as IL-17A, tumour necrosis factor alpha (TNF-α) and TNF-β, decreased when these cells were cocultured with supernatants derived from DPP4+ hASCs.

CONCLUSIONS

DPP4 may regulate proliferation, hepatocyte differentiation, inflammatory cytokine secretion and T-cell functionality of hASCs. These data provide a key foundation for understanding the important role of hASC subpopulations in the regulation of T cells, which may be helpful for future immune activation studies and allow them to be customized for clinical application.

Understanding Glycogen Synthase Kinase-3: A Novel Avenue for Alzheimer's Disease

Alzheimer's Disease (AD) is the most prevalent form of age-related dementia. Even though a century has passed since the discovery of AD, the exact cause of the disease still remains unknown. As a result, this poses a major hindrance in developing effective therapies for treating AD. Glycogen synthase kinase-3 (GSK-3) is one of the kinases that has been investigated recently as a potential therapeutic target for the treatment of AD. It is also known as human tau protein kinase and is a proline-directed serine-threonine kinase. Since dysregulation of this kinase affects all the major characteristic features of the disease, such as tau phosphorylation, amyloid formation, memory, and synaptic function, it is thought to be a major player in the pathogenesis of AD. In this review, we present the most recent information on the role of this kinase in the onset and progression of AD, as well as significant findings that identify GSK-3 as one of the most important targets for AD therapy. We further discuss the potential of treating AD by targeting GSK-3 and give an overview of the ongoing studies aimed at developing GSK-3 inhibitors in preclinical and clinical investigations.

Iloperidone and Temozolomide Synergistically Inhibit Growth, Migration and Enhance Apoptosis in Glioblastoma Cells

Glioblastoma (GBM) is a fatal astrocytic glioma with poor prognosis and treatment resistance. Repurposing potential FDA-approved drugs like anti-psychotics can address the concerns in a timely and cost-effective manner. Epidemiological studies have shown that patients with schizophrenic using anti-psychotics have a low incidence of GBM. Therefore, we aimed to investigate the therapeutic potential of atypical anti-psychotic Iloperidone (ILO) alone and in combination with Temozolomide (TMZ) against GBM. The study assessed the growth inhibitory effect of ILO, TMZ, and their combination (ILO + TMZ) on U-87MG and T-98G cell lines using an MTT assay. The drug interaction coefficient (CDI) was determined, and doses with synergistic effects were used for subsequent experiments, including migratory, invasion, and TUNEL assays. The expressions of DRD2, β-catenin, Dvl2, Twist, and Slug were assessed by RTq-PCR, whereas the β-catenin protein expression was also determined by immunocytochemistry. ILO (p < 0.05) and TMZ (p < 0.01) significantly inhibited the growth of U-87MG cells at all tested doses. The combination of 60 µM of both drugs showed synergistic activity with CDI < 1. The inhibition of migration and apoptosis was more pronounced in the case of combination treatment (p < 0.001). Inhibition of the invading cells was also found to be significant in ILO- and combination-treated groups (p < 0.001). ILO and combination treatment also significantly downregulated the expression of DRD2, while TMZ upregulated the expression (p < 0.001). The expressions of β-catenin (p < 0.001), Dvl2 (p < 0.001), Twist (p < 0.001), and Slug (p < 0.001) were also significantly downregulated in all treatment groups as compared to the vehicle control. The data suggest that ILO possesses strong growth inhibitory activity, possibly due to its effect on DRD2 and β-catenin expression and has the potential to be repurposed against GBM.

PAX1 represses canonical Wnt signaling pathway and plays dual roles during endoderm differentiation

BACKGROUND

Paired box 1 (PAX1) is a transcription factor and essential for the development of pharyngeal pouches-derived tissues, including thymus. PAX1 mutations are identified in Severe Combined Immunodeficiency (SCID) patients with Otofaciocervical Syndrome Type 2 (OTFCS2). However, despite the critical roles of PAX1 in embryonic development and diseases, detailed insights into its molecular mode of action are critically missing.

METHODS

The repressing roles of PAX1 and SCID associated mutants on Wnt signaling pathway were investigated by luciferase reporter assays, qRT-PCR and in situ hybridization in HEK293FT, HCT116 cells and zebrafish embryos, respectively. Co-immunoprecipitation (co-IP) and western blotting assays were carried out to identify the molecular mechanisms underlying PAX1's role on Wnt signaling pathway. hESC based endoderm differentiation, flow cytometry, high-throughput sequencing data analysis, and qRT-PCR assays were utilized to determine the roles of PAX1 during endoderm differentiation.

RESULTS

Here, we show that PAX1 represses canonical Wnt signaling pathway in vertebrate cells. Mechanically, PAX1 competes with SUMO E3 ligase PIASy to bind to TCF7L2, thus perturbing TCF7L2 SUMOylation level, further reducing its transcriptional activity and protein stability. Moreover, we reveal that PAX1 plays dual roles in hESC-derived definitive and foregut/pharyngeal endoderm cells, which give rise to the thymus epithelium, by inhibiting Wnt signaling. Importantly, our data show PAX1 mutations found in SCID patients significantly compromise the suppressing ability of PAX1 on Wnt signaling.

CONCLUSIONS

Our study presents a novel molecular mode of action of PAX1 in regulation of canonical Wnt signaling and endoderm differentiation, thus providing insights for the molecular basis of PAX1 associated SCID, offering better understanding of the behavior of PAX1 in embryogenesis.

Toward reproducible tumor organoid culture: focusing on primary liver cancer

Organoids present substantial potential for pushing forward preclinical research and personalized medicine by accurately recapitulating tissue and tumor heterogeneity in vitro. However, the lack of standardized protocols for cancer organoid culture has hindered reproducibility. This paper comprehensively reviews the current challenges associated with cancer organoid culture and highlights recent multidisciplinary advancements in the field with a specific focus on standardizing liver cancer organoid culture. We discuss the non-standardized aspects, including tissue sources, processing techniques, medium formulations, and matrix materials, that contribute to technical variability. Furthermore, we emphasize the need to establish reproducible platforms that accurately preserve the genetic, proteomic, morphological, and pharmacotypic features of the parent tumor. At the end of each section, our focus shifts to organoid culture standardization in primary liver cancer. By addressing these challenges, we can enhance the reproducibility and clinical translation of cancer organoid systems, enabling their potential applications in precision medicine, drug screening, and preclinical research.

Overexpression of Alpha-1 Antitrypsin Increases the Proliferation of Mesenchymal Stem Cells by Upregulation of Cyclin D1

Alpha-1 antitrypsin-overexpressing mesenchymal stromal/stem cells (AAT-MSCs) showed improved innate properties with a faster proliferation rate when studied for their protective effects in mouse models of diseases. Here, we investigated the potential mechanism(s) by which AAT gene insertion increases MSC proliferation. Human bone marrow-derived primary or immortalized MSCs (iMSCs) or AAT-MSCs (iAAT-MSCs) were used in the study. Cell proliferation was measured by cell counting and cell cycle analysis. Possible pathways involved in the pro-proliferation effect of AAT were investigated by measuring mRNA and protein expression of key cell cycle genes. Interval cell counting showed increased proliferation in AAT-MSCs or iAAT-MSCs compared to their corresponding MSC controls. Cell cycle analysis revealed more cells progressing into the S and G2/M phases in iAAT-MSCs, with a notable increase in the cell cycle protein, Cyclin D1. Moreover, treatment with Cyclin D1 inhibitors showed that the increase in proliferation is due to Cyclin D1 and that the AAT protein is upstream and a positive regulator of Cyclin D1. Furthermore, AAT's effect on Cyclin D1 is independent of the Wnt signaling pathway as there were no differences in the expression of regulatory proteins, including GSK3β and β-Catenin in iMSC and iAAT-MSCs. In summary, our results indicate that AAT gene insertion in an immortalized MSC cell line increases cell proliferation and growth by increasing Cyclin D1 expression and consequently causing cells to progress through the cell cycle at a significantly faster rate.

Tau, ADNP, and sex

With 50 years to the original discovery of Tau, I gave here my perspective, looking through the prism of activity-dependent neuroprotective protein (ADNP), and the influence of sex. My starting point was vasoactive intestinal peptide (VIP), a regulator of ADNP. I then moved to the original discovery of ADNP and its active neuroprotective site, NAP, drug candidate, davunetide. Tau-ADNP-NAP interactions were then explained with emphasis on sex and future translational medicine.

Urine-derived stem cells in neurological diseases: current state-of-the-art and future directions

Stem cells have potential applications in the field of neurological diseases, as they allow for the development of new biological models. These models can improve our understanding of the underlying pathologies and facilitate the screening of new therapeutics in the context of precision medicine. Stem cells have also been applied in clinical tests to repair tissues and improve functional recovery. Nevertheless, although promising, commonly used stem cells display some limitations that curb the scope of their applications, such as the difficulty of obtention. In that regard, urine-derived cells can be reprogrammed into induced pluripotent stem cells (iPSCs). However, their obtaining can be challenging due to the low yield and complexity of the multi-phased and typically expensive differentiation protocols. As an alternative, urine-derived stem cells (UDSCs), included within the population of urine-derived cells, present a mesenchymal-like phenotype and have shown promising properties for similar purposes. Importantly, UDSCs have been differentiated into neuronal-like cells, auspicious for disease modeling, while overcoming some of the shortcomings presented by other stem cells for these purposes. Thus, this review assesses the current state and future perspectives regarding the potential of UDSCs in the ambit of neurological diseases, both for disease modeling and therapeutic applications.

Overexpression of Alpha-1 Antitrypsin Increases the Proliferation of Mesenchymal Stem Cells by Upregulation of Cyclin D1 and is Independent of the Wnt Signaling Pathway

Alaph-1 antitrypsin overexpressing mesenchymal stromal/stem cells (AAT-MSCs) showed improved innate properties with a faster proliferation rate when studied for their protective effects in mouse models of diseases. Here, we investigated the potential mechanism(s) by which AAT gene insertion increases MSC proliferation. Human bone marrow-derived primary or immortalized MSCs (iMSCs) or AAT-MSCs (iAAT-MSCs) were used in the study. Cell proliferation was measured by cell counting and cell cycle analysis. Possible pathways involved in the pro-proliferation effect of AAT were investigated by measuring mRNA and protein expression of key cell cycle genes. Interval cell counting showed increased proliferation in AAT-MSCs or iAAT-MSCs compared to their corresponding MSC controls. Cell cycle analysis revealed more cells progressing into the S and G2/M phases in iAAT-MSCs, with a notable increase in the cell cycle protein, Cyclin D1. Moreover, treatment with Cyclin D1 inhibitors showed that the increase in proliferation is due to Cyclin D1 and that the AAT protein is upstream and a positive regulator of Cyclin D1. Furthermore, AAT's effect on Cyclin D1 is independent of the Wnt signaling pathway as there were no differences in the expression of regulatory proteins, including GSK3β and β-Catenin in iMSC and iAAT-MSCs. In summary, our results indicate that AAT gene insertion in an immortalized MSC cell line increases cell proliferation and growth by increasing Cyclin D1 expression and consequently causing cells to progress through the cell cycle at a significantly faster rate.

Honokiol inhibits epithelial-mesenchymal transition and hepatic fibrosis via activation of Ecadherin/GSK3β/JNK and inhibition of AKT/ERK/p38/β-catenin/TMPRSS4 signaling axis

Though Honokiol was known to have anti-inflammatory, antioxidant, anticancer, antithrombotic, anti-viral, metabolic, antithrombotic, and neurotrophic activities, the underlying mechanisms of Honokiol on epithelial-mesenchymal transition (EMT) mediated liver fibrosis still remain elusive so far. Anti-EMT and antifibrotic effects of Honokiol were explored in murine AML-12 hepatocyte cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, wound healing assay, Western blotting and also in CCl4-induced liver injury mouse model by immunohistochemistry. Honokiol significantly suppressed transforming growth factor β1 (TGF-β1)-induced EMT and migration of AML-12 cells along with decreased EMT phenotypes such as loss of cell adhesion and formation of fibroblast like mesenchymal cells in TGF-β1-treated AML-12 cells. Consistently, Honokiol suppressed the expression of Snail and transmembrane protease serine 4 (TMPRSS4), but not p-Smad3, and activated E-cadherin in TGF-β1-treated AML-12 cells. Additionally, Honokiol reduced the expression of β-catenin, p-AKT, p-ERK, p-p38 and increased phosphorylation of glycogen synthase kinase 3 beta (GSK3β) and JNK in TGF-β1-treated AML-12 cells via TGF-β1/nonSmad pathway. Conversely, GSK3β inhibitor SB216763 reversed the ability of Honokiol to reduce Snail, β-catenin and migration and activate E-cadherin in TGF-β1-treated AML-12 cells. Also, Honokiol suppressed hepatic steatosis and necrosis by reducing the expression of TGF-β1 and α-SMA in liver tissues of CCl4 treated mice. These findings provide scientific evidence that Honokiol suppresses EMT and hepatic fibrosis via activation of E-cadherin/GSK3β/JNK and inhibition of AKT/ERK/p38/β-catenin/TMPRSS4 signaling axis.

Differential sensitivity to Wnt signaling gradients in human gastric organoids derived from corpus and antrum

Wnt signaling regulates gastric stem cell proliferation and differentiation. Although similar Wnt gradients exist within the corpus and antrum of the human stomach, there are striking differences in gland architecture and disease manifestation that suggest Wnt may differentially regulate progenitor cell function in each compartment. In this study, we tested sensitivities to Wnt activation in human gastric corpus and antral organoids to determine whether progenitor cells have region-specific differences in Wnt responsiveness. Human patient-matched corpus and antral organoids were grown in the presence of varying concentrations of the Wnt pathway activator CHIR99021 to assess regional sensitivity to Wnt signaling on growth and proliferation. Corpus organoids were further studied to understand how high Wnt affected cellular differentiation and progenitor cell function. A lower concentration of CHIR99021 stimulated peak growth in corpus organoids compared with patient-matched antral organoids. Supramaximal Wnt signaling levels in corpus organoids suppressed proliferation, altered morphology, reduced surface cell differentiation, and increased differentiation of deep glandular neck and chief cells. Surprisingly, corpus organoids grown in high CHIR99021 had enhanced organoid forming potential, indicating that progenitor cell function was maintained in these nonproliferative, deep glandular cell-enriched organoids. Passaging high-Wnt quiescent organoids into low Wnt rescued normal growth, morphology, and surface cell differentiation. Our findings suggest that human corpus progenitor cells have a lower threshold for optimal Wnt signaling than antral progenitor cells. We demonstrate that Wnt signaling in the corpus regulates a bimodal axis of differentiation, with high Wnt promoting deep glandular cell differentiation and suppressing proliferation while simultaneously promoting progenitor cell function.NEW & NOTEWORTHY This study demonstrates that human gastric corpus organoids have a lower Wnt signaling threshold to drive optimal growth relative to patient-matched antral organoids. Paradoxically, supramaximal Wnt levels suppress corpus organoid proliferation, yet promote differentiation toward deep glandular cell types while simultaneously enhancing progenitor cell function. These findings provide novel insights into how Wnt signaling differentially regulates homeostasis in the human gastric corpus and antrum and contextualizes patterns of Wnt activation diseases.

Delineating the tumour-regulatory roles of EYA4

Eyes absent homolog 4 (EYA4) is a protein that regulates many vital cellular processes and organogenesis pathways. It possesses phosphatase, hydrolase, and transcriptional activation functions. Mutations in the Eya4 gene can cause sensorineural hearing loss and heart disease. In most non-nervous system cancers such as those of the gastrointestinal tract (GIT), hematological and respiratory systems, EYA4 acts as a putative tumor suppressor. However, in nervous system tumors such as glioma, astrocytoma, and malignant peripheral nerve sheath tumor (MPNST), it plays a putative tumor-promoting role. EYA4 interacts with various signaling proteins of the PI3K/AKT, JNK/cJUN, Wnt/GSK-3β, and cell cycle pathways to exert its tumor-promoting or tumor-suppressing effect. The tissue expression level and methylation profiles of Eya4 can help predict the prognosis and anti-cancer treatment response among cancer patients. Targeting and altering Eya4 expression and activity could be a potential therapeutic strategy to suppress carcinogenesis. In conclusion, EYA4 may have both putative tumor-promoting and tumor-suppressing roles in different human cancers and has the potential to serve as a prognostic biomarker and therapeutic agent in various cancer types.

The Role of Epicardial Adipose Tissue-Derived MicroRNAs in the Regulation of Cardiovascular Disease: A Narrative Review

Cardiovascular diseases have been leading cause of death worldwide for many decades, and obesity has been acknowledged as a risk factor for cardiovascular diseases. In the present review, human epicardial adipose tissue-derived miRNAs reported to be differentially expressed under pathologic conditions are discussed and summarized. The results of the literature review indicate that some of the epicardial adipose tissue-derived miRNAs are believed to be cardioprotective, while some others show quite the opposite effects depending on the underlying pathologic conditions. Furthermore, they suggest that that the epicardial adipose tissue-derived miRNAs have great potential as both a diagnostic and therapeutic modality. Nevertheless, mainly due to highly limited availability of human samples, it is very difficult to make any generalized claims on a given miRNA in terms of its overall impact on the cardiovascular system. Therefore, further functional investigation of a given miRNA including, but not limited to, the study of its dose effect, off-target effects, and potential toxicity is required. We hope that this review can provide novel insights to transform our current knowledge on epicardial adipose tissue-derived miRNAs into clinically viable therapeutic strategies for preventing and treating cardiovascular diseases.

The linker of nucleoskeleton and cytoskeleton complex is required for X-ray-induced epithelial-mesenchymal transition

The linker of nucleoskeleton and cytoskeleton (LINC) complex has been implicated in various functions of the nuclear envelope, including nuclear migration, mechanotransduction and DNA repair. We previously revealed that the LINC complex component Sad1 and UNC84 domain containing 1 (SUN1) is required for sublethal-dose X-ray-enhanced cell migration and invasion. This study focused on epithelial-mesenchymal transition (EMT), which contributes to cell migration. Hence, the present study aimed to examine whether sublethal-dose X-irradiation induces EMT and whether LINC complex component SUN1 is involved in low-dose X-ray-induced EMT. This study showed that low-dose (0.5 Gy or 2 Gy) X-irradiation induced EMT in human breast cancer MDA-MB-231 cells. Additionally, X-irradiation increased the expression of SUN1. Therefore, SUN1 was depleted using siRNA. In SUN1-depleted cells, low-dose X-irradiation did not induce EMT. In addition, although the SUN1 splicing variant SUN1_916-depleted cells (containing 916 amino acids [AA] of SUN1) were induced EMT by low-dose X-irradiation like as non-transfected control cells, SUN1_888-depleted cells (which encodes 888 AA) were not induced EMT by low-dose X-irradiation. Moreover, since the Wnt/β-catenin signaling pathway regulates E-cadherin expression via the expression of the E-cadherin repressor Snail, the expression of β-catenin after X-irradiation was examined. After 24 hours of irradiation, β-catenin expression increased in non-transfected cells or SUN1_916-depleted cells, whereas β-catenin expression remained unchanged and did not increase in SUN1- or SUN1_888-depleted cells. Therefore, in this study, we found that low-dose X-irradiation induces EMT, and LINC complex component SUN1, especially SUN1_888, is required for X-ray-induced EMT via activation of the Wnt/β-catenin signaling pathway.

Role of Nrf2 signaling in development of hepatocyte-like cells

Generation of hepatocytes from human adipose-derived mesenchymal stem cells (hADSCs) could be a promising alternative source of human hepatocytes. However, mechanisms to differentiate hepatocytes from hADSCs are not fully elucidated. We have previously demonstrated that our three-step differentiation protocol with glycogen synthase kinase (GSK) 3 inhibitor was effective to improve hepatocyte functions. In this study, we investigated the activation of the nuclear factor erythroid-2 related factor 2 (Nrf2) on hADSCs undergoing differentiation to HLC (hepatocyte-like cells). Our three-step differentiation protocol was applied for 21 days (Step 1:day 1-6, Step2:day 6-11, Step3:day 11-21). Our results show that significant nuclear translocation of Nrf2 occurred from day 11 until the end of HLC differentiation. Nuclear translocation of Nrf2 and CYP3A4 activity in the GSK3 inhibitor-treated group was obviously higher than that in Activin A-treated groups at day 11. The maturation of HLCs was delayed in Nrf2-siRNA group compared to control group. Furthermore, CYP3A4 activity in Nrf2-siRNA group was decreased at the almost same level in Activin A-treated group. Nrf2 translocation might enhance the function of HLC and be a target for developing highly functional HLC. J. Med. Invest. 70 : 343-349, August, 2023.

Integrative Multi-OMICs Identifies Therapeutic Response Biomarkers and Confirms Fidelity of Clinically Annotated, Serially Passaged Patient-Derived Xenografts Established from Primary and Metastatic Pediatric and AYA Solid Tumors

Establishment of clinically annotated, molecularly characterized, patient-derived xenografts (PDXs) from treatment-naïve and pretreated patients provides a platform to test precision genomics-guided therapies. An integrated multi-OMICS pipeline was developed to identify cancer-associated pathways and evaluate stability of molecular signatures in a panel of pediatric and AYA PDXs following serial passaging in mice. Original solid tumor samples and their corresponding PDXs were evaluated by whole-genome sequencing, RNA-seq, immunoblotting, pathway enrichment analyses, and the drug−gene interaction database to identify as well as cross-validate actionable targets in patients with sarcomas or Wilms tumors. While some divergence between original tumor and the respective PDX was evident, majority of alterations were not functionally impactful, and oncogenic pathway activation was maintained following serial passaging. CDK4/6 and BETs were prioritized as biomarkers of therapeutic response in osteosarcoma PDXs with pertinent molecular signatures. Inhibition of CDK4/6 or BETs decreased osteosarcoma PDX growth (two-way ANOVA, p < 0.05) confirming mechanistic involvement in growth. Linking patient treatment history with molecular and efficacy data in PDX will provide a strong rationale for targeted therapy and improve our understanding of which therapy is most beneficial in patients at diagnosis and in those already exposed to therapy.

Cocaine and Its Abstinence Condition Modulate Striatal and Hippocampal Wnt Signaling in a Male Rat Model of Drug Self-Administration

Recent years have provided more and more evidence confirming the important role of Wnt/β-catenin signaling in the pathophysiology of mental illnesses, including cocaine use disorder. High relapse rates, which is a hallmark of drug addiction, prompt the study of changes in Wnt signaling elements (Wnt5a, Wnt7b, and Ctnnb1) in the motivational aspects of cocaine use and early drug-free period (3 days after the last exposure to cocaine). For this purpose, an animal model of intravenous cocaine self-administration and two types of drug-free period (extinction training and abstinence in the home cage) were used. The studies showed that chronic cocaine self-administration mainly disturbs the expression of Wnt5a and Ctnnb1 (the gene encoding β-catenin) in the examined brain structures (striatum and hippocampus), and the examined types of early abstinence are characterized by a different pattern of changes in the expression of these genes. At the same time, in cocaine self-administrated animals, there were no changes in the level of Wnt5a and β-catenin proteins at the tested time points. Moreover, exposure to cocaine induces a significant reduction in the striatal and hippocampal expression of miR-374 and miR-544, which can regulate Wnt5a levels post-transcriptionally. In summary, previous observations from experimenter-administered cocaine have not been fully validated in the cocaine self-administration model. Yoked cocaine administration appears to disrupt Wnt signaling more than cocaine self-administration. The condition of the cocaine-free period, the routes of drug administration, and the motivational aspect of drug administration play an important role in the type of drug-induced molecular changes observed. Furthermore, in-depth research involving additional brain regions is needed to determine the exact role of Wnt signaling in short-term and long-lasting plasticity as well as in the motivational aspects of cocaine use, and thus to assess its potential as a target for new drug therapy for cocaine use disorder.

Epithelial coxsackievirus adenovirus receptor promotes house dust mite-induced lung inflammation

Airway inflammation and remodelling are important pathophysiologic features in asthma and other respiratory conditions. An intact epithelial cell layer is crucial to maintain lung homoeostasis, and this depends on intercellular adhesion, whilst damaged respiratory epithelium is the primary instigator of airway inflammation. The Coxsackievirus Adenovirus Receptor (CAR) is highly expressed in the epithelium where it modulates cell-cell adhesion stability and facilitates immune cell transepithelial migration. However, the contribution of CAR to lung inflammation remains unclear. Here we investigate the mechanistic contribution of CAR in mediating responses to the common aeroallergen, House Dust Mite (HDM). We demonstrate that administration of HDM in mice lacking CAR in the respiratory epithelium leads to loss of peri-bronchial inflammatory cell infiltration, fewer goblet-cells and decreased pro-inflammatory cytokine release. In vitro analysis in human lung epithelial cells confirms that loss of CAR leads to reduced HDM-dependent inflammatory cytokine release and neutrophil migration. Epithelial CAR depletion also promoted smooth muscle cell proliferation mediated by GSK3β and TGF-β, basal matrix production and airway hyperresponsiveness. Our data demonstrate that CAR coordinates lung inflammation through a dual function in leucocyte recruitment and tissue remodelling and may represent an important target for future therapeutic development in inflammatory lung diseases.

Hearing loss drug discovery and medicinal chemistry: Current status, challenges, and opportunities

Hearing loss is a severe high unmet need condition affecting more than 1.5 billion people globally. There are no licensed medicines for the prevention, treatment or restoration of hearing. Prosthetic devices, such as hearing aids and cochlear implants, do not restore natural hearing and users struggle with speech in the presence of background noise. Hearing loss drug discovery is immature, and small molecule approaches include repurposing existing drugs, combination therapeutics, late-stage discovery optimisation of known chemotypes for identified molecular targets of interest, phenotypic tissue screening and high-throughput cell-based screening. Hearing loss drug discovery requires the integration of specialist therapeutic area biology and otology clinical expertise. Small molecule drug discovery projects in the global clinical portfolio for hearing loss are here collated and reviewed. An overview is provided of human hearing, inner ear anatomy, inner ear delivery, types of hearing loss and hearing measurement. Small molecule experimental drugs in clinical development for hearing loss are reviewed, including their underpinning biology, discovery strategy and activities, medicinal chemistry, calculated physicochemical properties, pharmacokinetics and clinical trial status. SwissADME BOILED-Egg permeability modelling is applied to the molecules reviewed, and these results are considered. Non-small molecule hearing loss assets in clinical development are briefly noted in this review. Future opportunities in hearing loss drug discovery for human genomics and targeted protein degradation are highlighted.

Discovery of GSK3β Inhibitors through In Silico Prediction-and-Experiment Cycling Strategy, and Biological Evaluation

Direct inhibitors of glycogen synthase kinase 3β (GSK3β) have been investigated and reported for the past 20 years. In the search for novel scaffold inhibitors, 3000 compounds were selected through structure-based virtual screening (SBVS), and then high-throughput enzyme screening was performed. Among the active hit compounds, pyrazolo [1,5-a]pyrimidin-7-amine derivatives showed strong inhibitory potencies on the GSK3β enzyme and markedly activated Wnt signaling. The result of the molecular dynamics (MD) simulation, enhanced by the upper-wall restraint, was used as an advanced structural query for the SBVS. In this study, strong inhibitors designed to inhibit the GSK3β enzyme were discovered through SBVS. Our study provides structural insights into the binding mode of the inhibitors for further lead optimization.

Protein proximity networks and functional evaluation of the casein kinase 1 gamma family reveal unique roles for CK1γ3 in WNT signaling

Aberrant activation or suppression of WNT/β-catenin signaling contributes to cancer initiation and progression, neurodegeneration, and bone disease. However, despite great need and more than 40 years of research, targeted therapies for the WNT pathway have yet to be fully realized. Kinases are considered exceptionally druggable and occupy key nodes within the WNT signaling network, but several pathway-relevant kinases remain understudied and "dark." Here, we studied the function of the casein kinase 1γ (CSNK1γ) subfamily of human kinases and their roles in WNT signaling. miniTurbo-based proximity biotinylation and mass spectrometry analysis of CSNK1γ1, CSNK1γ2, and CSNK1γ3 revealed numerous components of the β-catenin-dependent and β-catenin-independent WNT pathways. In gain-of-function experiments, we found that CSNK1γ3 but not CSNK1γ1 or CSNK1γ2 activated β-catenin-dependent WNT signaling, with minimal effect on other signaling pathways. We also show that within the family, CSNK1γ3 expression uniquely induced low-density lipoprotein receptor-related protein 6 phosphorylation, which mediates downstream WNT signaling transduction. Conversely, siRNA-mediated silencing of CSNK1γ3 alone had no impact on WNT signaling, though cosilencing of all three family members decreased WNT pathway activity. Finally, we characterized two moderately selective and potent small-molecule inhibitors of the CSNK1γ family. We show that these inhibitors and a CSNK1γ3 kinase-dead mutant suppressed but did not eliminate WNT-driven low-density lipoprotein receptor-related protein 6 phosphorylation and β-catenin stabilization. Our data suggest that while CSNK1γ3 expression uniquely drives pathway activity, potential functional redundancy within the family necessitates loss of all three family members to suppress the WNT signaling pathway.

CUGBP1, a crucial factor for heart regeneration in mice

The mammalian heart is capable of achieving perfect regeneration following cardiac injury through sustained cardiomyocyte proliferation during the early period after birth. However, this regenerative capacity is lost by postnatal day 7 and throughout adulthood. CUGBP1 is critical for normal cardiac development but its role in heart regeneration remains unclear. Cardiac CUGBP1 levels are high in the early postnatal period and soon downregulate to adult levels within 1 week following birth in mice. The simultaneously diminished regenerative capacity and CUGBP1 levels by postnatal day lead us to hypothesize that CUGBP1 may be beneficial in heart regeneration. In this study, the function of CUGBP1 in heart regeneration was tested by a heart apex resection mouse model. We demonstrate that cardiac inactivation of CUGBP1 impairs neonatal heart regeneration at P1, in turn, replenishment of CUGBP1 levels prolong regenerative potential at P8 and P14. Furthermore, our results imply that the Wnt/β-catenin signaling and GATA4 involve in the CUGBP1 modulated neonatal heart regeneration. Altogether, our findings support CUGBP1 as a key factor promoting post-injury heart regeneration and provide a potential therapeutic method for heart disease.

Liraglutide Improves Cognitive and Neuronal Function in 3-NP Rat Model of Huntington's Disease

Huntington’s disease (HD) is an autosomal dominant inherited neurodegenerative disease characterized by progressive motor, psychiatric, and cognitive abnormalities. The antidiabetic drug liraglutide possesses a neuroprotective potential against several neurodegenerative disorders; however, its role in Huntington’s disease (HD) and the possible mechanisms/trajectories remain elusive, which is the aim of this work. Liraglutide (200 μg/kg, s.c) was administered to rats intoxicated with 3-nitropropionic acid (3-NP) for 4 weeks post HD model induction. Liraglutide abated the 3-NP-induced neurobehavioral deficits (open field and elevated plus maze tests) and histopathological changes. Liraglutide downregulated the striatal mRNA expression of HSP 27, PBR, and GFAP, while it upregulated that of DARPP32. On the molecular level, liraglutide enhanced striatal miR-130a gene expression and TrKB protein expression and its ligand BDNF, while it reduced the striatal protein content and mRNA expression of the death receptors sortilin and p75NTR, respectively. It enhanced the neuroprotective molecules cAMP, p-PI3K, p-Akt, and p-CREB, besides modulating the p-GSK-3β/p-β-catenin axis. Liraglutide enhanced the antioxidant transcription factor Nrf2, abrogated TBARS, upregulated both Bcl2 and Bcl-XL, and downregulated Bax along with decreasing caspase-3 activity. Therefore, liraglutide exerts a neurotherapeutic effect on 3-NP-treated rats that is, besides the upturn of behavioral and structural findings, it at least partially, increased miR-130a and modulated PI3K/Akt/CREB/BDNF/TrKB, sortilin, and p75NTR, and Akt/GSK-3β/p-β-catenin trajectories besides its capacity to decrease apoptosis and oxidative stress, as well as its neurotrophic activity.

Inhibition of T-antigen expression promoting glycogen synthase kinase 3 impairs merkel cell carcinoma cell growth

Merkel cell carcinoma is an aggressive skin cancer frequently caused by the Merkel cell polyomavirus (MCPyV). Since proliferation of MCPyV-positive MCC tumor cells strictly depends on expression of the virus-encoded T antigens (TA), these proteins theoretically represent ideal targets for different kinds of therapeutic approaches. Here we developed a cell-based assay to identify compounds which specifically inhibit growth of MCC cells by repressing TA expression. Applying this technique we screened a kinase inhibitor library and identified six compounds targeting glycogen synthase kinase 3 (GSK3) such as CHIR99021 as suppressors of TA transcription in MCC cells. Involvement of GSK3α and -β in the regulation of TA-expression was confirmed by combining GSK3A knockout with inducible GSK3B shRNA knockdown since double knockouts could not be generated. Finally, we demonstrate that CHIR99021 exhibits in vivo antitumor activity in an MCC xenograft mouse model suggesting GSK3 inhibitors as potential therapeutics for the treatment of MCC in the future.

GSK3β Interacts With CRMP2 and Notch1 and Controls T-Cell Motility

The trafficking of T-cells through peripheral tissues and into afferent lymphatic vessels is essential for immune surveillance and an adaptive immune response. Glycogen synthase kinase 3β (GSK3β) is a serine/threonine kinase and regulates numerous cell/tissue-specific functions, including cell survival, metabolism, and differentiation. Here, we report a crucial involvement of GSK3β in T-cell motility. Inhibition of GSK3β by CHIR-99021 or siRNA-mediated knockdown augmented the migratory behavior of human T-lymphocytes stimulated via an engagement of the T-cell integrin LFA-1 with its ligand ICAM-1. Proteomics and protein network analysis revealed ongoing interactions among GSK3β, the surface receptor Notch1 and the cytoskeletal regulator CRMP2. LFA-1 stimulation in T-cells reduced Notch1-dependent GSK3β activity by inducing phosphorylation at Ser9 and its nuclear translocation accompanied by the cleaved Notch1 intracellular domain and decreased GSK3β-CRMP2 association. LFA-1-induced or pharmacologic inhibition of GSK3β in T-cells diminished CRMP2 phosphorylation at Thr514. Although substantial amounts of CRMP2 were localized to the microtubule-organizing center in resting T-cells, this colocalization of CRMP2 was lost following LFA-1 stimulation. Moreover, the migratory advantage conferred by GSK3β inhibition in T-cells by CHIR-99021 was lost when CRMP2 expression was knocked-down by siRNA-induced gene silencing. We therefore conclude that GSK3β controls T-cell motility through interactions with CRMP2 and Notch1, which has important implications in adaptive immunity, T-cell mediated diseases and LFA-1-targeted therapies.

Induction and Maturation of Hepatocyte-Like Cells In Vitro: Focus on Technological Advances and Challenges

Limited by the poor proliferation and restricted sources of adult hepatocytes, there is an urgent need to find substitutes for proliferation and cultivation of mature hepatocytes in vitro for use in disease treatment, drug approval, and toxicity testing. Hepatocyte-like cells (HLCs), which originate from undifferentiated stem cells or modified adult cells, are considered good candidates because of their advantages in terms of cell source and in vitro expansion ability. However, the majority of induced HLCs are in an immature state, and their degree of differentiation is heterogeneous, diminishing their usability in basic research and limiting their clinical application. Therefore, various methods have been developed to promote the maturation of HLCs, including chemical approaches, alteration of cell culture systems, and genetic manipulation, to meet the needs of in vivo transplantation and in vitro model establishment. This review proposes different cell types for the induction of HLCs, and provide a comprehensive overview of various techniques to promote the generation and maturation of HLCs in vitro.

Efficient hepatic differentiation and regeneration potential under xeno-free conditions using mass-producible amnion-derived mesenchymal stem cells

BACKGROUND

Amnion-derived mesenchymal stem cells (AM-MSCs) are an attractive source of stem cell therapy for patients with irreversible liver disease. However, there are obstacles to their use due to low efficiency and xeno-contamination for hepatic differentiation.

METHODS

We established an efficient protocol for differentiating AM-MSCs into hepatic progenitor cells (HPCs) by analyzing transcriptome-sequencing data. Furthermore, to generate the xeno-free conditioned differentiation protocol, we replaced fetal bovine serum (FBS) with polyvinyl alcohol (PVA). We investigated the hepatocyte functions with the expression of mRNA and protein, secretion of albumin, and activity of CYP3A4. Finally, to test the transplantable potential of HPCs, we transferred AM-MSCs along with hepatic progenitors after differentiated days 11, 12, and 13 based on the expression of hepatocyte-related genes and mitochondrial function. Further, we established a mouse model of acute liver failure using a thioacetamide (TAA) and cyclophosphamide monohydrate (CTX) and transplanted AM-HPCs in the mouse model through splenic injection.

RESULTS

We analyzed gene expression from RNA sequencing data in AM-MSCs and detected downregulation of hepatic development-associated genes including GATA6, KIT, AFP, c-MET, FGF2, EGF, and c-JUN, and upregulation of GSK3. Based on this result, we established an efficient hepatic differentiation protocol using the GSK3 inhibitor, CHIR99021. Replacing FBS with PVA resulted in improved differentiation ability, such as upregulation of hepatic maturation markers. The differentiated hepatocyte-like cells (HLCs) not only synthesized and secreted albumin, but also metabolized drugs by the CYP3A4 enzyme. The best time for translation of AM-HPCs was 12 days from the start of differentiation. When the AM-HPCs were transplanted into the liver failure mouse model, they settled in the damaged livers and differentiated into hepatocytes.

CONCLUSION

This study offers an efficient and xeno-free conditioned hepatic differentiation protocol and shows that AM-HPCs could be used as transplantable therapeutic materials. Thus, we suggest that AM-MSC-derived HPCs are promising cells for treating liver disease.

A genetic screen in macrophages identifies new regulators of IFNγ-inducible MHCII that contribute to T cell activation

Cytokine-mediated activation of host immunity is central to the control of pathogens. Interferon-gamma (IFNγ) is a key cytokine in protective immunity that induces major histocompatibility complex class II molecules (MHCII) to amplify CD4⁺ T cell activation and effector function. Despite its central role, the dynamic regulation of IFNγ-induced MHCII is not well understood. Using a genome-wide CRISPR-Cas9 screen in murine macrophages, we identified genes that control MHCII surface expression. Mechanistic studies uncovered two parallel pathways of IFNγ-mediated MHCII control that require the multifunctional glycogen synthase kinase three beta (GSK3β) or the mediator complex subunit 16 (MED16). Both pathways control distinct aspects of the IFNγ response and are necessary for IFNγ-mediated induction of the MHCII transactivator Ciita, MHCII expression, and CD4⁺ T cell activation. Our results define previously unappreciated regulation of MHCII expression that is required to control CD4⁺ T cell responses.

Functions of Intracellular Alpha-Synuclein in Microglia: Implications for Parkinson's Disease Risk

Alpha-synuclein accumulation in dopaminergic neurons is one of the primary features of Parkinson’s disease (PD). Despite its toxic properties during PD, alpha-synuclein has some important physiological functions. Although the activity of the protein has been extensively studied in neurons, the protein is also expressed in other cell types including immune cells and glia. Genetic studies show that mutations in synuclein alpha (SNCA), the gene that encodes alpha-synuclein, and alterations in its expression levels are a significant risk factor for PD, which likely impact the functions of a broad range of cell types. The consequences of altered SNCA expression in other cell types is beginning to be explored. Microglia, the primary macrophage population in the Central Nervous System (CNS), for example, are affected by variations in alpha-synuclein levels and functions. Studies suggest that deviations of alpha-synuclein’s normal activity influence hematopoiesis, the process that gives rise to microglia, and microglia’s immune functions. Alpha-synuclein levels also dictate the efficiency of SNARE-mediated vesicle formation, which could influence autophagy and cytokine release in microglia. Starting from the time of conception, these effects could impact one’s risk for developing PD. Further studies are needed to determine the physiological role of alpha-synuclein and how the protein is affected during PD in non-neuronal cells such as microglia. In this review we will discuss the known roles of alpha-synuclein in differentiation, immune responses, and vesicle formation, with insights into how abnormal alpha-synuclein expression and activity are linked to altered functions of microglia during PD.

The Role of Small Molecules and Their Effect on the Molecular Mechanisms of Early Retinal Organoid Development

Early in vivo embryonic retinal development is a well-documented and evolutionary conserved process. The specification towards eye development is temporally controlled by consecutive activation or inhibition of multiple key signaling pathways, such as the Wnt and hedgehog signaling pathways. Recently, with the use of retinal organoids, researchers aim to manipulate these pathways to achieve better human representative models for retinal development and disease. To achieve this, a plethora of different small molecules and signaling factors have been used at various time points and concentrations in retinal organoid differentiations, with varying success. Additions differ from protocol to protocol, but their usefulness or efficiency has not yet been systematically reviewed. Interestingly, many of these small molecules affect the same and/or multiple pathways, leading to reduced reproducibility and high variability between studies. In this review, we make an inventory of the key signaling pathways involved in early retinogenesis and their effect on the development of the early retina in vitro. Further, we provide a comprehensive overview of the small molecules and signaling factors that are added to retinal organoid differentiation protocols, documenting the molecular and functional effects of these additions. Lastly, we comparatively evaluate several of these factors using our established retinal organoid methodology.

Thyroid Hormone Effect on the Differentiation of Human Induced Pluripotent Stem Cells into Hepatocyte-Like Cells

Human induced pluripotent stem cells (hiPSCs) hold great potential as an unlimited source for obtaining hepatocyte-like cells (HLCs) for drug research. However, current applications of HLCs have been severely limited by the inability to produce mature hepatocytes from hiPSCs in vitro. Thyroid hormones are one of the hormones that surge during the perinatal period when liver maturation takes place. Here we assessed the influence of thyroid hormone on hepatic progenitor differentiation to HLCs. We analyzed gene and protein expression of early and late hepatic markers and demonstrated the selective activity of thyroid hormone on different genes. Particularly, we demonstrated thyroid hormone-dependent inhibition of the fetal hepatic marker AFP. Our study sheds light on the role of thyroid hormone during liver differentiation and maturation.

Microtubule-targeting agents impair kinesin-2-dependent nuclear transport of β-catenin: Evidence of inhibition of Wnt/β-catenin signaling as an important antitumor mechanism of microtubule-targeting agents

An aberrant accumulation of nuclear β-catenin is closely associated with the augmentation of cancer malignancy. In this work, we report that several microtubule-targeting agents (MTAs) such as vinblastine, taxol, and C12 (combretastatin-2-aminoimidazole analog) inhibit Wnt/β-catenin signaling in oral squamous cell carcinoma (OSCC). We showed that the inhibition of microtubule dynamics by MTAs decreased the level of β-catenin by increasing Axin and adenomatous polyposis coli levels and reducing the level of dishevelled. Furthermore, MTAs strongly reduced the localization of β-catenin in the nucleus. The reduction in the level of nuclear β-catenin was neither due to the degradation of β-catenin in the nucleus nor due to an increase in the export of nuclear β-catenin from the nucleus. A motor protein kinesin-2 was found to assist the nuclear transportation of β-catenin. Interestingly, Wnt/β-catenin signaling antagonist treatment synergized with MTAs and the activators of Wnt/β-catenin signaling antagonized with the MTAs. C12 potently suppressed the growth of 4-Nitroquinoline 1-oxide-induced OSCC in the tongue of C57 black 6 mice and also abrogated Wnt/β-catenin signaling pathway in the tumor. Our results provide evidence that the decrease in Wnt/β-catenin signaling is an important antitumor effect of MTAs and the combined use of MTAs with Wnt/β-catenin signaling antagonists could be a promising strategy for cancer chemotherapy.

AMPK Is the Crucial Target for the CDK4/6 Inhibitors Mediated Therapeutic Responses in PANC-1 and MIA PaCa-2 Pancreatic Cancer Cell Lines

The survival rate of pancreatic ductal adenocarcinoma (PDAC) patients is short, and PDAC is a cancer type that ranks fourth in the statistics regarding death due to cancer. Mutation in the KRAS gene, which plays a role in pancreatic cancer development, activates the PI3K/AKT/mTOR signaling pathway. The activity of the AMPK as a cellular energy sensor is one of the fundamental mechanisms that can induce effective therapeutic responses against CDK4/6 inhibitors via adjusting the cellular and tumor microenvironment stress management. The phosphorylation of AMPKα at the different phosphorylation residues such as Thr172 and Ser 377 causes metabolic differentiation in the cells following CDK4/6 inhibitor treatment in accordance with an increased cell cycle arrest and senescence under the control of different cellular players. In this study, we examined the competencies of the CDK4/6 inhibitors LY2835219 and PD-0332991 on the mechanism of cell survival and death based on AMPK signaling. Both CDK4/6 inhibitors LY2835219 and PD-0332991 modulated different molecular players on the PI3K/AKT/mTOR and AMPK signaling axis in different ways to reduce cell survival in a cell type dependent manner. These drugs are potential inducers of apoptosis and senescence that can alter the therapeutic efficacy cells.

Selective activation of FZD7 promotes mesendodermal differentiation of human pluripotent stem cells

WNT proteins are secreted symmetry breaking signals that interact with cell surface receptors of the FZD family to regulate a multitude of developmental processes. Studying selectivity between WNTs and FZDs has been hampered by the paucity of purified WNT proteins and by their apparent non-selective interactions with the FZD receptors. Here, we describe an engineered protein, called F7L6, comprised of antibody-derived single-chain variable fragments, that selectively binds to human FZD7 and the co-receptor LRP6. F7L6 potently activates WNT/β-catenin signaling in a manner similar to Wnt3a. In contrast to Wnt3a, F7L6 engages only FZD7 and none of the other FZD proteins. Treatment of human pluripotent stem (hPS) cells with F7L6 initiates transcriptional programs similar to those observed during primitive streak formation and subsequent gastrulation in the mammalian embryo. This demonstrates that selective engagement and activation of FZD7 signaling is sufficient to promote mesendodermal differentiation of hPS cells.

Therapeutic Potential of Apatinib Against Colorectal Cancer by Inhibiting VEGFR2-Mediated Angiogenesis and β-Catenin Signaling

Purpose

Apatinib is an inhibitor of VEGFR2 (vascular endothelial growth factor receptor 2) that has attracted a great deal of attention due to its promotion of anticancer activity. In the present study, we investigated the therapeutic effects of apatinib against colorectal cancer (CRC) and examined the underlying mechanism.

Materials and Methods

Both in vivo and in vitro assays were conducted to study the effect of apatinib on CRC. To elucidate the associated mechanism, RNA-seq (transcriptome) analysis was conducted on apatinib-treated HCT116 cells.

Results

Apatinib showed antiproliferative and proapoptotic effects, induced G0/G1 arrest and blocked cell migration and invasion in CRC. An analysis of the mechanism associated with apatinib activity demonstrated that by interacting with VEGFR2, apatinib decreased p-Src, p-Akt, and p-GSK3β levels, which further increased β-catenin ubiquitination and reduced the nuclear translocation of β-catenin. Furthermore, apatinib strongly suppressed CT26 cell growth in mouse xenograft models by inhibiting β-catenin signaling and angiogenesis.

Conclusion

Overall, the results of the present study here indicated that by inhibiting the VEGFR2-β-catenin-mediated malignant phenotype, apatinib significantly suppresses the growth of CRC, suggesting that the use of apatinib is a promising therapeutic strategy for CRC.

Current status of hepatocyte-like cell therapy from stem cells

Organ liver transplantation and hepatocyte transplantation are not performed to their full potential because of donor shortage, which could be resolved by identifying new donor sources for the development of hepatocyte-like cells (HLCs). HLCs have been differentiated from some stem cell sources as alternative primary hepatocytes throughout the world; however, the currently available techniques cannot differentiate HLCs to the level of normal adult primary hepatocytes. The outstanding questions are as follows: which stem cells are the best cell sources? which protocol is the best way to differentiate them into HLCs? what is the definition of differentiated HLCs? how can we enforce the function of HLCs? what is the difference between HLCs and primary hepatocytes? what are the problems with HLC transplantation? This review summarizes the current status of HLCs, focusing on stem cell sources, the differentiation protocol for HLCs, the general characterization of HLCs, the generation of more functional HLCs, comparison with primary hepatocytes, and HLCs in cell-transplantation-based liver regeneration.

HNF4A and GATA6 Loss Reveals Therapeutically Actionable Subtypes in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) can be divided into transcriptomic subtypes with two broad lineages referred to as classical (pancreatic) and squamous. We find that these two subtypes are driven by distinct metabolic phenotypes. Loss of genes that drive endodermal lineage specification, HNF4A and GATA6, switch metabolic profiles from classical (pancreatic) to predominantly squamous, with glycogen synthase kinase 3 beta (GSK3β) a key regulator of glycolysis. Pharmacological inhibition of GSK3β results in selective sensitivity in the squamous subtype; however, a subset of these squamous patient-derived cell lines (PDCLs) acquires rapid drug tolerance. Using chromatin accessibility maps, we demonstrate that the squamous subtype can be further classified using chromatin accessibility to predict responsiveness and tolerance to GSK3β inhibitors. Our findings demonstrate that distinct patterns of chromatin accessibility can be used to identify patient subgroups that are indistinguishable by gene expression profiles, highlighting the utility of chromatin-based biomarkers for patient selection in the treatment of PDAC.

Epigenetics of SFRP1: The Dual Roles in Human Cancers

Secreted frizzled-related protein 1 (SFRP1) is a gene that belongs to the secreted glycoprotein SFRP family. SFRP1 has been classified as a tumor suppressor gene due to the loss of expression in various human cancers, which is mainly attributed by epigenetic inactivation via DNA methylation or transcriptional silencing by microRNAs. Epigenetic silencing of SFRP1 may cause dysregulation of cell proliferation, migration, and invasion, which lead to cancer cells formation, disease progression, poor prognosis, and treatment resistance. Hence, restoration of SFRP1 expression via demethylating drugs or over-expression experiments opens the possibility for new cancer therapy approach. While the role of SFRP1 as a tumor suppressor gene is well-established, some studies also reported the possible oncogenic properties of SFRP1 in cancers. In this review, we discussed in great detail the dual roles of SFRP1 in cancers-as tumor suppressor and tumor promoter. The epigenetic regulation of SFRP1 expression will also be underscored with additional emphasis on the potentials of SFRP1 in modulating responses toward chemotherapeutic and epigenetic-modifying drugs, which may encourage the development of novel drugs for cancer treatment. We also present findings from clinical trials and patents involving SFRP1 to illustrate its clinical utility, extensiveness of each research area, and progression toward commercialization. Lastly, this review provides directions for future research to advance SFRP1 as a promising cancer biomarker.

Glycogen synthase kinase 3β inhibitor- CHIR 99021 augments the differentiation potential of mesenchymal stem cells

AIM

Mesenchymal stem cells (MSCs) are immunomodulatory, non-teratogenic and multipotent alternatives to embryonic or induced pluripotent stem cells (ESCs or iPSCs). However, the potency of MSCs is not equivalent to the pluripotency of ESCs or iPSCs. We used CHIR 99021 to improve current protocols and methods of differentiation for the enhanced transdifferentiation potency of MSCs.

MAIN METHODS

We used Flurescence activated cell sorter (FACS) for MSC immunophenotyping and biochemical assay for demonstrating the trilineage potential of MSCs. We used real-time polymerase chain reaction, immunocytochemistry and Western blotting assay for analyzing the expression of lineage-specific markers.

KEY FINDINGS

CHIR 99021 treatment of MSCs resulted in enhanced transdifferentiation into neurological, hepatogenic and cardiomyocyte lineages with standardized protocols of differentiation. CHIR 99021-treated MSCs showed increased nuclear localization of β-catenin. These MSCs showed a significantly increased deposition of active histone marks (H3K4Me3, H3K36Me3), whereas no change was observed in repressive marks (H3K9Me3, H3K27Me3). Differential methylation profiling showed demethylation of the transcription factor OCT4 promoter region with subsequent analysis revealing increased gene expression and protein content. The HLA-DR antigen was absent in CHIR 99021-treated MSCs and their differentiated cell types, indicating their immune-privileged status. Karyotyping analysis showed that CHIR 99021-treated MSCs were genomically stable. Teratoma analysis of nude mice injected with CHIR 99021-treated MSCs showed the increased presence of cell types of mesodermal origin at the site of injection.

SIGNIFICANCE

MSCs pretreated with CHIR 99021 can be potent, abundant alternative sources of stem cells with enhanced differentiation capabilities that are well suited to cell-based regenerative therapy.