Glycogen Synthase Kinase-3 Inhibitors Research Articles

Elraglusib induces cytotoxicity via direct microtubule destabilization independently of GSK3 inhibition.

Elraglusib (9-ING-41) is an ATP-competitive inhibitor of glycogen synthase kinase-3 (GSK3) with pre-clinical studies demonstrating broad activity against many tumour types. Promising early-phase clinical trial data led to FDA orphan drug status, and a randomized phase 2 study in combination with cytotoxic chemotherapy in pancreatic cancer has recently completed its recruitment. Similarly, single-agent responses in adult T-cell leukaemia/lymphoma and melanoma, and combination treatment data in several other tumour types have been encouraging. The elraglusib mechanism of action is unknown, but it is unlikely to act through GSK3 inhibition because cytotoxicity is observed below the IC50 for GSK3 and other small molecule GSK3 inhibitors do not produce cytotoxic effects, at least in lymphoma cells. We show here that elraglusib perturbs chromosomal alignment to cause a mitotic arrest in multiple tumour lines. This arrest is caused by direct microtubule depolymerization, which prevents the attachment of kinetochores to microtubules. At clinically relevant doses, these mitotically arrested cells eventually undergo mitotic slippage, leading to gross chromosome missegregation, DNA damage and apoptosis. These effects explain the cytotoxicity of elraglusib because temporarily pausing cell cycle progression with the CDK4/6 inhibitor palbociclib abolishes any drug-induced genotoxicity and apoptosis. In summary, elraglusib acts as a direct microtubule destabilizer both in vitro and across multiple cancer types, resulting in mitotic arrest, DNA damage and apoptosis. These effects likely account for its broad pan-cancer activity, which does not rely upon GSK3 inhibition as they are not replicated by other GSK3 inhibitors.

Glycogen synthase kinase 3 (GSK3) inhibition: a potential therapeutic strategy for Alzheimer's disease.

Alzheimer's disease (AD), the most common type of dementia among older adults, is a chronic neurodegenerative pathology that causes a progressive loss of cognitive functioning with a decline of rational skills. It is well known that AD is multifactorial, so there are many different pharmacological targets that can be pursued. According to estimates from the World Health Organization (WHO), 18 million individuals worldwide suffer from AD. Major initiatives to identify risk factors, enhance care giving, and conduct basic research to delay the beginning of AD were started by the USA, France, Germany, France, and various other nations. Widely recognized as a key player in the development and subsequent progression of AD pathogenesis, glycogen synthase kinase-3 (GSK-3) controls a number of crucial targets associated with neuronal degeneration. GSK-3 inhibition has been linked to reduced tau hyperphosphorylation, β-amyloid formation, and neuroprotective benefits in Alzheimer's disease. Lithium, the very first inhibitor ofGSK-3βthat was used therapeutically,has been successfully used for many years with remarkable results. A great variety of structurally varied strong GSK-3β blockers have been identified in recent years. The purpose of this thorough review is to cover the biological and structural elements of glycogen synthase kinase, as well as the medicinal chemistry aspects of GSK inhibitors that have been produced in recent years.

Stanniocalcin 2 Promotes Neuronal Differentiation in Neural Stem/Progenitor Cells of the Mouse Subventricular Zone Through Activation of AKT Pathway.

Neural stem/progenitor cells (NSPCs) persist in the mammalian subventricular zone (SVZ) throughout life, responding to various pathophysiological stimuli and playing a crucial role in central nervous system repair. Although numerous studies have elucidated the role of stanniocalcin 2 (STC2) in regulating cell differentiation processes, its specific function in NSPCs differentiation remains poorly understood. Clarifying the role of STC2 in NSPCs is essential for devising novel strategies to enhance the intrinsic potential for brain regeneration postinjury. Our study revealed the expression of STC2 in NSPCs derived from the SVZ of the C57BL/6N mouse. In cultured SVZ-derived NSPCs, STC2 treatment significantly increased the number of Tuj1 and DCX-positive cells. Furthermore, STC2 injection into the lateral ventricle promoted the neuronal differentiation of NSPCs and migration to the olfactory bulb. Conversely, the STC2 knockdown produced the opposite effect. Further investigation showed that STC2 treatment enhanced AKT phosphorylation in cultured NSPCs, whereas STC2 inhibition hindered AKT activation. Notably, the neuronal differentiation induced by STC2 was blocked by the AKT inhibitor GSK690693, whereas the AKT activator SC79 reversed the impact of STC2 knockdown on neuronal differentiation. Our findings indicate that enhancing STC2 expression in SVZ-derived NSPCs facilitates neuronal differentiation, with AKT regulation potentially serving as a key intracellular target of STC2 signaling.

Targeted inhibition of glycogen synthase kinase-3 using 9-ING-41 (elraglusib) enhances CD8 T-cell-reactivity against neuroblastoma cells

The prognosis of patients with high-risk neuroblastoma remains poor, partly due to inadequate immune recognition of the tumor. Neuroblastomas display extremely low surface MHC-I, preventing recognition by cytotoxic T lymphocytes (CTLs) and contributing to an immunosuppressive tumor microenvironment. Glycogen synthase kinase-3 beta (GSK-3β) is involved in pathways that may affect the MHC-I antigen processing and presentation pathway. We proposed that therapeutic inhibition of GSK-3β might improve the surface display of MHC-I molecules on neuroblastoma cells, and therefore tested if targeting of GSK-3β using the inhibitor 9-ING-41 (Elraglusib) improves MHC-I-mediated CTL recognition. We analyzed mRNA expression data of neuroblastoma tumor datasets and found that non-MYCN-amplified neuroblastomas express higher GSK-3β levels than MYCN-amplified tumors. In non-MYCN-amplified cells SH-SY5Y, SK-N-AS and SK-N-SH 9-ING-41 treatment enhanced MHC-I surface display and the expression levels of a subset of genes involved in MHC-I antigen processing and presentation. Further, 9-ING-41 treatment triggered increased STAT1 pathway activation, upstream of antigen presentation pathways in two of the three non-MYCN-amplified cell lines. Finally, in co-culture experiments with CD8 + T cells, 9-ING-41 improved immune recognition of the neuroblastoma cells, as evidenced by augmented T-cell activation marker levels and T-cell proliferation, which was further enhanced by PD-1 immune checkpoint inhibition. Our preclinical study provides experimental support to further explore the GSK-3β inhibitor 9-ING-41 as an immunomodulatory agent to increase tumor immune recognition in neuroblastoma.

Quantitative label-free digital holographic imaging of cardiomyocyte optical volume, nucleation, and cell division

Cardiac regeneration in newborn rodents depends on the ability of pre-existing cardiomyocytes to proliferate and divide. This capacity is lost within the first week of postnatal development when these cells rapidly switch from hyperplasia to hypertrophy, withdraw from the cell cycle, become binucleated, and increase in size. How these dynamic changes in cell size and nucleation impact cardiomyocyte proliferative potential is not well understood. In this study, we innovate the application of a commercially available digital holographic imaging microscope, the Holomonitor M4, to evaluate the proliferative responses of mononucleated and binucleated cardiomyocytes after CHIR99021 treatment, a model proliferative stimulus. This system enables long-term label-free quantitative tracking of primary cardiomyocyte dynamics in real-time with single-cell resolution. Our results confirm that chemical inhibition of glycogen synthase kinase 3 with CHIR99021 promotes complete cell division of both mononucleated and binucleated cardiomyocytes with high frequency. Quantitative tracking of cardiomyocyte volume dynamics during these proliferative events revealed that both mononucleated and binucleated cardiomyocytes reach a similar size-increase threshold prior to attempted cell division. Binucleated cardiomyocytes attempt to divide with lower frequency than mononucleated cardiomyocytes, which may be associated with inadequate increases in cell size. By defining the interrelationship between cardiomyocyte size, nucleation, and cell cycle control, we may better understand the cellular mechanisms that drive the loss of mammalian cardiac regenerative capacity after birth.

Wnt signaling activation confers a syncytiotrophoblast progenitor state on trophoblast stem cells of cynomolgus monkey.

Trophoblast stem cells (TSCs), derived from the trophectoderm of the blastocyst, are used as an in vitro model to reveal the mechanisms underlying placentation in mammals. In humans, suitable culture conditions for TSC derivation have recently been established. The established human TSCs (hTSCs) differentiate efficiently toward two trophoblast subtypes: syncytiotrophoblasts (STBs) and extravillous trophoblasts (EVTs). However, the efficiency of differentiation is lower in macaque TSCs than in hTSCs. Here, we demonstrate that the activation of Wnt signaling downregulated the expression of inhibitory G protein and induced trophoblastic lineage switching to the STB progenitor state. The treatment of macaque TSCs with a GSK-3 inhibitor, CHIR99021, upregulated STB progenitor markers and enhanced proliferation. Under the Wnt signaling-activated conditions, macaque TSCs effectively differentiated to STBs upon dbcAMP and forskolin treatment. RNA-seq analyses revealed the downregulation of inhibitory G protein, which may make macaque TSCs responsive to forskolin. Interestingly, this lineage switching appeared to be reversible as the macaque TSCs lost responsiveness to forskolin upon the removal of CHIR99021. The ability to regulate the direction of macaque TSC differentiation would be advantageous in elucidating the mechanisms underlying placentation in non-human primates.

Generation of human hepatobiliary organoids with a functional bile duct from chemically induced liver progenitor cells

BackgroundLiver disease imposes a significant medical burden that persists due to a shortage of liver donors and an incomplete understanding of liver disease progression. Hepatobiliary organoids (HBOs) could provide an in vitro mini-organ model to increase the understanding of the liver and may benefit the development of regenerative medicine.MethodsIn this study, we aimed to establish HBOs with bile duct (BD) structures and mature hepatocytes (MHs) using human chemically induced liver progenitor cells (hCLiPs). hCLiPs were induced in mature cryo-hepatocytes using a small-molecule cocktail of TGF-β inhibitor (A-83-01, A), GSK3 inhibitor (CHIR99021, C), and 10% FBS (FAC). HBOs were then formed by seeding hCLiPs into ultralow attachment plates and culturing them with a combination of small molecules of Rock-inhibitor (Y-27632) and AC (YAC).ResultsThese HBOs exhibited bile canaliculi of MHs connected to BD structures, mimicking bile secretion and transportation functions of the liver. The organoids showed gene expression patterns consistent with both MHs and BD structures, and functional assays confirmed their ability to transport the bile analogs of rhodamine-123 and CLF. Functional patient-specific HBOs were also successfully created from hCLiPs sourced from cirrhotic liver tissues.ConclusionsThis study demonstrated the potential of human HBOs as an efficient model for studying hepatobiliary diseases, drug discovery, and personalized medicine.

Rhythms in lipid droplet content driven by a metabolic oscillator are conserved throughout evolution

The biological clock in eukaryotes controls daily rhythms in physiology and behavior. It displays a complex organization that involves the molecular transcriptional clock and the redox oscillator which may coordinately work to control cellular rhythms. The redox oscillator has emerged very early in evolution in adaptation to the environmental changes in O2 levels and has been shown to regulate daily rhythms in glycerolipid (GL) metabolism in different eukaryotic cells. GLs are key components of lipid droplets (LDs), intracellular storage organelles, present in all living organisms, and essential for energy and lipid homeostasis regulation and survival; however, the cell bioenergetics status is not constant across time and depends on energy demands. Thus, the formation and degradation of LDs may reflect a time-dependent process following energy requirements. This work investigated the presence of metabolic rhythms in LD content along evolution by studying prokaryotic and eukaryotic cells and organisms. We found sustained temporal oscillations in LD content in Pseudomonas aeruginosa bacteria and Caenorhabditis elegans synchronized by temperature cycles, in serum-shock synchronized human embryonic kidney cells (HEK 293 cells) and brain tumor cells (T98G and GL26) after a dexamethasone pulse. Moreover, in synchronized T98G cells, LD oscillations were altered by glycogen synthase kinase-3 (GSK-3) inhibition that affects the cytosolic activity of the metabolic oscillator or by knocking down LIPIN-1, a key GL synthesizing enzyme. Overall, our findings reveal the existence of metabolic oscillations in terms of LD content highly conserved across evolutionary scales notwithstanding variations in complexity, regulation, and cell organization.Graphical abstract

GSK3 inhibition reduces ECM production and prevents age-related macular degeneration-like pathology.

Malattia Leventinese/Doyne honeycomb retinal dystrophy (ML/DHRD) is an age-related macular degeneration-like (AMD-like) retinal dystrophy caused by an autosomal dominant R345W mutation in the secreted glycoprotein, fibulin-3 (F3). To identify new small molecules that reduce F3 production in retinal pigmented epithelium (RPE) cells, we knocked-in a luminescent peptide tag (HiBiT) into the endogenous F3 locus that enabled simple, sensitive, and high-throughput detection of the protein. The GSK3 inhibitor, CHIR99021 (CHIR), significantly reduced F3 burden (expression, secretion, and intracellular levels) in immortalized RPE and non-RPE cells. Low-level, long-term CHIR treatment promoted remodeling of the RPE extracellular matrix, reducing sub-RPE deposit-associated proteins (e.g., amelotin, complement component 3, collagen IV, and fibronectin), while increasing RPE differentiation factors (e.g., tyrosinase, and pigment epithelium-derived factor). In vivo, treatment of 8-month-old R345W+/+ knockin mice with CHIR (25 mg/kg i.p., 1 mo) was well tolerated and significantly reduced R345W F3-associated AMD-like basal laminar deposit number and size, thereby preventing the main pathological feature in these mice. This is an important demonstration of small molecule-based prevention of AMD-like pathology in ML/DHRD mice and may herald a rejuvenation of interest in GSK3 inhibition for the treatment of retinal degenerative diseases, including potentially AMD itself.

Inhibition of GSK3α,β rescues cognitive phenotypes in a preclinical mouse model of CTNNB1 syndrome

CTNNB1 syndrome is a rare monogenetic disorder caused by CTNNB1 de novo pathogenic heterozygous loss-of-function variants that result in cognitive and motor disabilities. Treatment is currently lacking; our study addresses this critical need. CTNNB1 encodes β-catenin which is essential for normal brain function via its dual roles in cadherin-based synaptic adhesion complexes and canonical Wnt signal transduction. We have generated a Ctnnb1 germline heterozygous mouse line that displays cognitive and motor deficits, resembling key features of CTNNB1 syndrome in humans. Compared with wild-type littermates, Ctnnb1 heterozygous mice also exhibit decreases in brain β-catenin, β-catenin association with N-cadherin, Wnt target gene expression, and Na/K ATPases, key regulators of changes in ion gradients during high activity. Consistently, hippocampal neuron functional properties and excitability are altered. Most important, we identify a highly selective inhibitor of glycogen synthase kinase (GSK)3α,β that significantly normalizes the phenotypes to closely meet wild-type littermate levels. Our data provide new insights into brain molecular and functional changes, and the first evidence for an efficacious treatment with therapeutic potential for individuals with CTNNB1 syndrome.

Combined inhibition of EZH2 and CDK4/6 perturbs endoplasmic reticulum-mitochondrial homeostasis and increases antitumor activity against glioblastoma

Here, we show that combined use of the EZH2 inhibitor GSK126 and the CDK4/6 inhibitor abemaciclib synergistically enhances antitumoral effects in preclinical GBM models. Dual blockade led to HIF1α upregulation and CalR translocation, accompanied by massive impairment of mitochondrial function. Basal oxygen consumption rate, ATP synthesis, and maximal mitochondrial respiration decreased, confirming disrupted endoplasmic reticulum-mitochondrial homeostasis. This was paralleled by mitochondrial depolarization and upregulation of the UPR sensors PERK, ATF6α, and IRE1α. Notably, dual EZH2/CDK4/6 blockade also reduced 3D-spheroid invasion, partially inhibited tumor growth in ovo, and led to impaired viability of patient-derived organoids. Mechanistically, this was due to transcriptional changes in genes involved in mitotic aberrations/spindle assembly (Rb, PLK1, RRM2, PRC1, CENPF, TPX2), histone modification (HIST1H1B, HIST1H3G), DNA damage/replication stress events (TOP2A, ATF4), immuno-oncology (DEPDC1), EMT-counterregulation (PCDH1) and a shift in the stemness profile towards a more differentiated state. We propose a dual EZH2/CDK4/6 blockade for further investigation.

Crosstalk among WEE1 Kinase, AKT, and GSK3 in Nav1.2 Channelosome Regulation.

The signaling complex around voltage-gated sodium (Nav) channels includes accessory proteins and kinases crucial for regulating neuronal firing. Previous studies showed that one such kinase, WEE1-critical to the cell cycle-selectively modulates Nav1.2 channel activity through the accessory protein fibroblast growth factor 14 (FGF14). Here, we tested whether WEE1 exhibits crosstalk with the AKT/GSK3 kinase pathway for coordinated regulation of FGF14/Nav1.2 channel complex assembly and function. Using the in-cell split luciferase complementation assay (LCA), we found that the WEE1 inhibitor II and GSK3 inhibitor XIII reduce the FGF14/Nav1.2 complex formation, while the AKT inhibitor triciribine increases it. However, combining WEE1 inhibitor II with either one of the other two inhibitors abolished its effect on the FGF14/Nav1.2 complex formation. Whole-cell voltage-clamp recordings of sodium currents (INa) in HEK293 cells co-expressing Nav1.2 channels and FGF14-GFP showed that WEE1 inhibitor II significantly suppresses peak INa density, both alone and in the presence of triciribine or GSK3 inhibitor XIII, despite the latter inhibitor's opposite effects on INa. Additionally, WEE1 inhibitor II slowed the tau of fast inactivation and caused depolarizing shifts in the voltage dependence of activation and inactivation. These phenotypes either prevailed or were additive when combined with triciribine but were outcompeted when both WEE1 inhibitor II and GSK3 inhibitor XIII were present. Concerted regulation by WEE1 inhibitor II, triciribine, and GSK3 inhibitor XIII was also observed in long-term inactivation and use dependency of Nav1.2 currents. Overall, these findings suggest a complex role for WEE1 kinase-in concert with the AKT/GSK3 pathway-in regulating the Nav1.2 channelosome.

A cellular senescence-related signature for predicting prognosis, immunotherapy response, and candidate drugs in patients treated with transarterial chemoembolization (TACE)

BackgroundCellular senescence is essential to TME development, progression, and remodeling. Few studies have examined cellular senescence in HCC after TACE. Investigating the relationship between cellular senescence, post-TACE prognosis, the TME, and immune treatment responses is crucial.MethodsWe analyzed the GSE104580 dataset to identify DEGs. A cellular senescence-related signature was developed using LASSO Cox regression in the GSE14520 dataset and validated in the ICGC dataset. High- and low-risk subgroups were compared using GSVA and GSEA. Correlation studies were conducted to explore the relationship between the prognostic model, immune infiltration, immunotherapy response, and drug sensitivity.ResultsA cellular senescence-related signature comprising FOXM1, CDK1, CHEK1, and SERPINE1 was created and validated. High-risk patients showed significantly lower OS than low-risk patients. High-risk patients had carcinogenetic pathways activated, immunosuppressive cells infiltrated, and immunomodulatory genes overexpressed. They also showed higher sensitivity to EPZ004777_1237 and MK-2206_1053 and potential benefits from GSK-3 inhibitor IX, nortriptyline, lestaurtinib, and JNK-9L.ConclusionsThis study constructed a cellular senescence-related signature that could be used to predict HCC patients’ responses to and prognosis after TACE treatment, aiding in the development of personalized treatment plans.

GSK3: A potential target and pending issues for treatment of Alzheimer's disease.

Glycogen synthase kinase-3 (GSK3), consisting of GSK3α and GSK3β subtypes, is a complex protein kinase that regulates numerous substrates. Research has observed increased GSK3 expression in the brains of Alzheimer's disease (AD) patients and models. AD is a neurodegenerative disorder with diverse pathogenesis and notable cognitive impairments, characterized by Aβ aggregation and excessive tau phosphorylation. This article provides an overview of GSK3's structure and regulation, extensively analyzing its relationship with AD factors. GSK3 overactivation disrupts neural growth, development, and function. It directly promotes tau phosphorylation, regulates amyloid precursor protein (APP) cleavage, leading to Aβ formation, and directly or indirectly triggers neuroinflammation and oxidative damage. We also summarize preclinical research highlighting the inhibition of GSK3 activity as a primary therapeutic approach for AD. Finally, pending issues like the lack of highly specific and affinity-driven GSK3 inhibitors, are raised and expected to be addressed in future research. In conclusion, GSK3 represents a target in AD treatment, filled with hope, challenges, opportunities, and obstacles.

Pharmacological Modulation of the Cytosolic Oscillator Affects Glioblastoma Cell Biology

The circadian system is a conserved time-keeping machinery that regulates a wide range of processes such as sleep/wake, feeding/fasting, and activity/rest cycles to coordinate behavior and physiology. Circadian disruption can be a contributing factor in the development of metabolic diseases, inflammatory disorders, and higher risk of cancer. Glioblastoma (GBM) is a highly aggressive grade 4 brain tumor that is resistant to conventional therapies and has a poor prognosis after diagnosis, with a median survival of only 12–15 months. GBM cells kept in culture were shown to contain a functional circadian oscillator. In seeking more efficient therapies with lower side effects, we evaluated the pharmacological modulation of the circadian clock by targeting the cytosolic kinases glycogen synthase kinase-3 (GSK-3) and casein kinase 1 ε/δ (CK1ε/δ) with specific inhibitors (CHIR99021 and PF670462, respectively), the cryptochrome protein stabilizer (KL001), or circadian disruption after Per2 knockdown expression in GBM-derived cells. CHIR99021-treated cells had a significant effect on cell viability, clock protein expression, migration, and cell cycle distribution. Moreover, cultures exhibited higher levels of reactive oxygen species and alterations in lipid droplet content after GSK-3 inhibition compared to control cells. The combined treatment of CHIR99021 with temozolomide was found to improve the effect on cell viability compared to temozolomide therapy alone. Per2 disruption affected both GBM migration and cell cycle progression. Overall, our results suggest that pharmacological modulation or molecular clock disruption severely affects GBM cell biology.

Wnt/β-catenin-YAP axis in the pathogenesis of primary intraosseous carcinoma NOS, deriving from odontogenic keratocyst

Odontogenic tumors (OGTs), which originate from cells of odontogenic apparatus and their remnants, are rare entities. Primary intraosseous carcinoma NOS (PIOC), is one of the OGTs, but it is even rarer and has a worse prognosis. The precise characteristics of PIOC, especially in immunohistochemical features and its pathogenesis, remain unclear. We characterized a case of PIOC arising from the left mandible, in which histopathological findings showed a transition from the odontogenic keratocyst to the carcinoma. Remarkably, the tumor lesion of this PIOC prominently exhibits malignant attributes, including invasive growth of carcinoma cell infiltration into the bone tissue, an elevated Ki-67 index, and lower signal for CK13 and higher signal for CK17 compared with the non-tumor region, histopathologically and immunohistopathologically. Further immunohistochemical analyses demonstrated increased expression of ADP-ribosylation factor (ARF)-like 4c (ARL4C) (accompanying expression of β-catenin in the nucleus) and yes-associated protein (YAP) in the tumor lesion. On the other hand, YAP was expressed and the expression of ARL4C was hardly detected in the non-tumor region. In addition, quantitative RT-PCR analysis using RNAs and dot blot analysis using genomic DNA showed the activation of Wnt/β-catenin signaling and epigenetic alterations, such as an increase of 5mC levels and a decrease of 5hmC levels, in the tumor lesion. A DNA microarray and a gene set enrichment analysis demonstrated that various types of intracellular signaling would be activated and several kinds of cellular functions would be altered in the pathogenesis of PIOC. Experiments with the GSK-3 inhibitor revealed that β-catenin pathway increased not only mRNA levels of ankyrin repeat domain1 (ANKRD1) but also protein levels of YAP and transcriptional co-activator with PDZ-binding motif (TAZ) in oral squamous cell carcinoma cell lines. These results suggested that further activation of YAP signaling by Wnt/β-catenin signaling may be associated with the pathogenesis of PIOC deriving from odontogenic keratocyst in which YAP signaling is activated.

GSK-3β/Notch-1 Activation Promotes Radiation-Induced Renal Damage: The Role of Gallic Acid in Mitigation of Nephrotoxicity.

Despite the therapeutic advances in treating malignancies, the efficient radiotherapeutic approaches with deprived adverse reactions still represent a potential clinical inquiry. The current study aims to elucidate the role of gallic acid (GA) in modifying the hazardous renal cytotoxicity induced by acute exposure to radiation. The MTT test was used to evaluate the viability of Vero cells exposed to 2 Gy gamma radiation with or without incubation of GA. In an in vivo model, male Wistar rats were divided into four experimental groups (n = 6): Control, Irradiated (IRR, 5 Gy), GA (100 mg/kg, i.p.) + IRR, and Glycogen synthase kinase inhibitor (GSKI, 3 mg/kg, i.p.) + IRR. Based on the MTT toxicity assay, from 0 and up to 5 μM dosages of GA did not demonstrate any cytotoxicity to Vero cells. The optimal GA dose that could protect the cells from radiation was 5 μM. Furthermore, GA exerted a protective effect from gamma radiation on renal tissue as indicated by corrected renal functions, decreased LDH level in serum, and balanced oxidative status, which is indicated by decreased tissue contents of NOx and TBARS with a significant increase of reduced GSH. These outcomes were inferred by the upregulation of nuclear factor erythroid 2-related factor 2 (Nrf2) expression. The overall molecular impact of radiation in damaging the renal tissue may be explained by modifying the upstream AKT activity and its downstream targets GSK-3β/Notch-1. Here, we concluded that the anticipated adverse reaction in the course of radiation exposure could be protected by daily administration of GA.

Targeting IL-11R/EZH2 signaling axis as a therapeutic strategy for osteosarcoma lung metastases

Lung metastases are the primary cause of death for osteosarcoma (OS) patients. We recently validated interleukin-11 receptor α (IL-11Rα) as a molecular target for the inhibition of OS lung metastases. Since there is no clinically approved antibody against this receptor, we sought to identify downstream targets that mediate the effects of IL-11Rα signaling. We used shRNA to deplete IL-11Rα from OS cells; as a complementary approach, we added IL-11 exogenously to OS cells. The resulting changes in gene expression identified EZH2 as a downstream candidate. This was confirmed by knockdown of IL-11Rα in OS cells, which led to increased expression of genes repressed by histone methyltransferase EZH2, including members of the WNT pathway, a known target pathway of EZH2. Exogenous IL-11 increased the global levels of histone H3 lysine 27 trimethylation, evidence of EZH2 activation. Treatment with the EZH2 inhibitor GSK126 significantly reduced in vitro proliferation and increased cell-cycle arrest and apoptosis, which were partially mediated through the WNT pathway. In vivo, treatment of an orthotopic nude mouse model of OS with GSK126 inhibited lung metastatic growth and prolonged survival. In addition, significantly shorter recurrence-free survival was seen in OS patients with high levels of EZH2 in their primary tumors (P < .05). This suggests that IL-11Rα promotes OS lung metastasis via activation of EZH2. Thus, blocking EZH2 activity may be an effective strategy for inhibiting OS lung metastasis and improving prognosis.

New edaravone analogs incorporated with N‐benzylthiazole moiety: Multistep chemical synthesis, in vitro cytotoxicity with pRIPK3 inhibitory activities, and molecular docking

AbstractIn this research article, the chemical synthesis of new N‐phenylpyrazolone‐N‐benzylthiazole hybrids (3–6) via late‐stage thiazolation of the corresponding benzylthiosemicarbazone 2 was reported. The skeletal structural of the new molecules were validated by instrumental measurements (FT‐IR, NMR, and EI‐MS). In vitro cytotoxicity‐based cellular MTT bioassay shows that compound 3 that bears an N‐benzyl‐4‐thiazolone moiety is the most potent one toward the osteosarcoma cell line (Hos) with an IC50 value of 5.8 ± 0.1 μM, while compound 4a that contains a 5‐acetyl‐N‐benzylthiazole unit is the most robust one against the model lung carcinoma cell line (A549) with an IC50 value of 9.23 ± 0.01 μM. Also, 3 is roughly equipotent to 4b in its cytotoxicity activity against A549. In vitro enzymatic ELISA bioassay of A549 cells indicates that IC50 of 3 caused a decrease in the pRIPK3 kinase concentration (2.89 ± 0.005 pg/mL) as compared to DMSO‐treated cells (2.93 ± 0.010 pg/mL), while the pRIPK3 level incresed with 4b impact. As a result, 3 may be an effective inhibitor of pRIPK3 and hence necroptosis, proposing a novel therapeutic strategy for necroptosis‐related illnesses. In silico molecular docking shows that 3 interlocked and fitted well into the binding site of RIPK3 (PDB code: 7MX3) with a fitness value (−123.382 kcal/mol) lower than 4b and forms an important H‐bond with Lys50 like the marketed RIPK3 inhibitor GSK'843, validating the experimental results. Consequently, 3 is the most promising molecule that could be a lead candidate for further studies.

Correlation of therapy-induced neutropenia with survival in patients with metastatic pancreatic cancer treated with GSK-3 inhibitor elraglusib (9-ING-41) in combination with gemcitabine/nab-paclitaxel in the 1801 phase 2 study.

e16311 Background: Previously, elraglusib (9-ING-41), an inhibitor of Glycogen Synthase Kinase-3 (GSK-3), was shown to potentiate the anticancer effects of chemotherapeutic drugs in preclinical models of cancer. The combination of elraglusib and gemcitabine/nab-paclitaxel (GnP) is currently being investigated in a randomized, open-label 1801 phase 2 study as a first-line therapy for patients with metastatic pancreatic ductal adenocarcinoma (mPDAC). Chemotherapy-induced neutropenia is a common dose-limiting toxicity resulting in dose reductions and/or treatment interruptions. Present evidence shows that therapy-induced neutropenia (TIN) grade 3-4 correlates with survival and is a potential marker for improved clinical outcome in elraglusib/GnP-treated patients. Methods: We correlated overall survival (OS) and time-to-treatment discontinuation (TTD) with TIN grade 3-4 in 72 (GnP arm) and 155 (elraglusib/GnP arm) mPDAC patients previously untreated for advanced disease (1801 Part 3 Arm B study; NCT03678883). TTD was defined as the date of first dose to the date of treatment discontinuation or death. The Kaplan-Meier log-rank test was used for statistical analysis. A p-value &lt; 0.05 was considered statistically significant. Results: The rate of grade 3-4 TIN was 22% (16/72 patients) and 47% (72/155 patients) in the GnP and elraglusib/GnP groups, respectively. Based on 28% of all recorded death events in elraglusib/GnP group and 36% in GnP group, we found that grade 3-4 TIN was significantly associated with improved OS in patients treated with elraglusib/GnP (median OS: 14.4 vs 5.9 months; P &lt; 0.05) but not in patients treated with GnP (median OS: 7.6 vs 7.2 months). In the elraglusib/GnP group, patients with grade 3-4 TIN stayed on treatment significantly longer (median TTD: 7.9 months; P &lt; 0.05) as compared to the patients who did not develop TIN grade 3-4 (median TTD: 1.7 months). Conclusions: Our preliminary results identified grade 3-4 TIN as a potential marker of improved clinical outcome for elraglusib/GnP therapy in previously untreated patients with mPDAC. Recruitment for the 1801 Part 3 Arm B phase 2 trial has been completed. Another interim analysis of OS and its correlation to grade 3-4 TIN will be available by April 2024 and will be included in the final presentation. Clinical trial information: NCT03678883 .