Engineering and evaluation of FXa bypassing agents that restore hemostasis following Apixaban associated bleeding.

Direct oral anticoagulants (DOACs) targeting activated factor Xa (FXa) are used to prevent or treat thromboembolic disorders. DOACs reversibly bind to FXa and inhibit its enzymatic activity. However, DOAC treatment carries the risk of anticoagulant-associated bleeding. Currently, only one specific agent, andexanet alfa, is approved to reverse the anticoagulant effects of FXa-targeting DOACs (FXaDOACs) and control life-threatening bleeding. However, because of its mechanism of action, andexanet alfa requires a cumbersome dosing schedule, and its use is associated with the risk of thrombosis. Here, we present the computational design, engineering, and evaluation of FXa-variants that exhibit anticoagulation reversal activity in the presence of FXaDOACs. Our designs demonstrate low DOAC binding affinity, retain FXa-enzymatic activity and reduce the DOAC-associated bleeding by restoring hemostasis in mice treated with apixaban. Importantly, the FXaDOACs reversal agents we designed, unlike andexanet alfa, do not inhibit TFPI, and consequently, may have a safer thrombogenic profile.

Simulating BRAFV600E-MEK-ERK signalling dynamics in response to vertical inhibition treatment strategies.

In vertical inhibition treatment strategies, multiple components of an intracellular pathway are simultaneously inhibited. Vertical inhibition of the BRAFV600E-MEK-ERK signalling pathway is a standard of care for treating BRAFV600E-mutated melanoma where two targeted cancer drugs, a BRAFV600E-inhibitor, and a MEK inhibitor, are administered in combination. Targeted therapies have been linked to early onsets of drug resistance, and thus treatment strategies of higher complexities and lower doses have been proposed as alternatives to current clinical strategies. However, finding optimal complex, low-dose treatment strategies is a challenge, as it is possible to design more treatment strategies than are feasibly testable in experimental settings. To quantitatively address this challenge, we develop a mathematical model of BRAFV600E-MEK-ERK signalling dynamics in response to combinations of the BRAFV600E-inhibitor dabrafenib (DBF), the MEK inhibitor trametinib (TMT), and the ERK-inhibitor SCH772984 (SCH). From a model of the BRAFV600E-MEK-ERK pathway, and a set of molecular-level drug-protein interactions, we extract a system of chemical reactions that is parameterised by in vitro data and converted to a system of ordinary differential equations (ODEs) using the law of mass action. The ODEs are solved numerically to produce simulations of how pathway-component concentrations change over time in response to different treatment strategies, i.e., inhibitor combinations and doses. The model can thus be used to limit the search space for effective treatment strategies that target the BRAFV600E-MEK-ERK pathway and warrant further experimental investigation. The results demonstrate that DBF and DBF-TMT-SCH therapies show marked sensitivity to BRAFV600E concentrations in silico, whilst TMT and SCH monotherapies do not.

Pirfenidone and nintedanib exert additive antifibrotic effects by the SPP1-AKT pathway in macrophages and fibroblasts.

Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive disease with high mortality rates. It has been shown that pirfenidone (PFD) and nintedanib (Ofev) can slow down the decline in lung function of IPF patients, but their efficacy remains suboptimal. Some studies have suggested that the combination of PFD and Ofev may yield promising results. However, there is a lack of research on the combined application of these two medications in the treatment of IPF. A mouse model of bleomycin-induced (BLM) pulmonary fibrosis was established to investigate the impact of combination therapy on pulmonary fibrosis of mice. The findings demonstrated a significant reduction in lung tissue damage in mice treated with the combination therapy. Subsequent transcriptome analysis identified the differential gene secreted phosphoprotein 1 (SPP1), which was found to be associated with macrophages and fibroblasts based on multiple immunofluorescence staining results. Analysis of a phosphorylated protein microarray indicated that SPP1 plays a regulatory role in macrophages and fibroblasts via the AKT pathway. Consequently, the regulation of macrophages and fibroblasts in pulmonary fibrosis by the combination of PFD and Ofev is mediated by SPP1 through the AKT pathway, potentially offering a novel therapeutic option for IPF patients. Further investigation into the targeting of SPP1 for the treatment of pulmonary fibrosis is warranted.

Dolutegravir and Folic Acid Interaction during Neural System Development in Zebrafish Embryos.

Dolutegravir (DTG) is one of the most prescribed antiretroviral drugs for treating people with HIV infection, including women of child-bearing potential or pregnant. Nonetheless, neuropsychiatric symptoms are frequently reported. Early reports suggested that, probably in relation to folic acid (FA) shortage, DTG may induce neural tube defects in infants born to women taking the drug during pregnancy. Subsequent reports did not definitively confirm these findings. Recent studies in animal models have highlighted the association between DTG exposure in utero and congenital anomalies, and an increased risk of neurologic abnormalities in children exposed during in utero life has been reported. Underlying mechanisms for DTG-related neurologic symptoms and congenital anomalies are not fully understood. We aimed to deepen our knowledge on the neurodevelopmental effects of DTG exposure and further explore the protective role of FA by the use of zebrafish embryos. We treated embryos at 4 and up to 144 h post fertilization (hpf) with a subtherapeutic DTG concentration (1 µM) and observed the disruption of the anterior-posterior axis and several morphological malformations in the developing brain that were both prevented by pre-exposure (2 hpf) and rescued by post-exposure (10 hpf) with FA. By whole-mount in situ hybridization with riboprobes for genes that are crucial during the early phases of neurodevelopment (ntl, pax2a, ngn1, neurod1) and by in vivo visualization of the transgenic Tg(ngn1:EGFP) zebrafish line, we found that DTG induced severe neurodevelopmental defects over time in most regions of the nervous system (notochord, midbrain-hindbrain boundary, eye, forebrain, midbrain, hindbrain, spinal cord) that were mostly but not completely rescued by FA supplementation. Of note, we observed the disruption of ngn1 expression in the dopaminergic regions of the developing forebrain, spinal cord neurons and spinal motor neuron projections, with the depletion of the tyrosine hydroxylase (TH)+ dopaminergic neurons of the dorsal diencephalon and the strong reduction in larvae locomotion. Our study further supports previous evidence that DTG can interfere with FA pathways in the developing brain but also provides new insights regarding the mechanisms involved in the increased risk of DTG-associated fetal neurodevelopmental defects and adverse neurologic outcomes in in utero exposed children, suggesting the impairment of dopaminergic pathways.

Hispidin Increases Cell Apoptosis and Ferroptosis in Prostate Cancer Cells Through Phosphatidylinositol-3-Kinase and Mitogen-activated Protein Kinase Signaling Pathway.

BACKGROUND/AIM: Chemotherapy is mainly used in the clinical treatment of prostate cancer. Different anticancer mechanisms can induce cell death in various cancers. Reactive oxygen species (ROS) play crucial roles in cell proliferation, differentiation, apoptosis, and signal transduction. It is widely accepted that ROS accumulation is closely related to chemical drug-induced cancer cell death. MATERIALS AND METHODS: We utilized the MTT assay to detect changes in cell proliferation. Additionally, colony formation and wound healing assay were conducted to investigate the effect of hispidin on cell colony formation and migration ability. Fluorescence microscopy was used to detect intracellular and mitochondrial ROS levels, while western blot was used for detection of cell apoptosis. RESULTS: Hispidin treatment significantly decreased viability of PC3 and DU145 cancer cells but exhibited no cytotoxicity in WPMY-1 cells. Furthermore, hispidin treatment inhibited cell migration and colony formation and triggered cellular and mitochondrial ROS accumulation, leading to mitochondrial dysfunction and mitochondrion-dependent apoptosis. Moreover, hispidin treatment induced ferroptosis in PC3 cells. Scavenging of ROS with N-acetyl cysteine significantly inhibited hispidin-induced apoptosis by altering the expression of apoptosis-related proteins, such as cleaved caspase-3, 9, Bax, and Bcl2. Furthermore, hispidin treatment dramatically up-regulated MAPK (involving p38, ERK, and JNK proteins) and NF-kB signaling pathways while down-regulating AKT phosphorylation. Hispidin treatment also inhibited ferroptosis signaling pathways (involving P53, Nrf-2, and HO-1 proteins) in PC3 cells. In addition, inhibiting these signaling pathways via treatment with specific inhibitors significantly reversed hispidin-induced apoptosis, cellular ROS levels, mitochondrial dysfunction, and ferroptosis. CONCLUSION: Hispidin may represent a potential candidate for treating prostate cancer.

Effects of hypromellose acetate succinate on recrystallization inhibition, miscibility, and dissolution enhancement of baloxavir marboxil solid dispersions.

Solid dispersions (SDs) have emerged as a promising strategy to enhance the solubility and bioavailability of poorly soluble active pharmaceutical ingredients. However, SDs tend to recrystallize unless suitable excipients are utilized. This study aimed to facilitate the rational selection of polymers and formulation design by evaluating the impact of various polymers on the miscibility, and phase behavior of SDs using baloxavir marboxil (BXM) with a high crystallization tendency as a model drug. Meanwhile, the effects of these polymers on the solubility enhancement and recrystallization inhibition were also assessed. The results indicated that the miscibility limit of BXM for HPMCAS was around 40 % drug loading (DL), whereas for PVP, PVPVA, and HPMC approximately 20 % DL. The BXM-HPC system exhibited limited miscibility with DL of 10 % or higher. BXM SDs based on various polymers exhibited varying degrees of spontaneous phase separation once DL exceeded the miscibility limit. Interestingly, a correlation was discovered between the phase separation behavior and the ability of the polymer to inhibit recrystallization. BXM-HPMCAS SDs exhibited optimal dissolution performance, compared with other systems. In conclusion, the physicochemical properties of polymers significantly influence BXM SDs performance and the BXM-HPMCAS SDs might promote an efficient and stable drug delivery system.

Extracellular vesicles promote migration despite BRAF inhibitor treatment in malignant melanoma cells.

Extracellular vesicles (EVs) constitute a vital component of intercellular communication, exerting significant influence on metastasis formation and drug resistance mechanisms. Malignant melanoma (MM) is one of the deadliest forms of skin cancers, because of its high metastatic potential and often acquired resistance to oncotherapies. The prevalence of BRAF mutations in MM underscores the importance of BRAF-targeted therapies, such as vemurafenib and dabrafenib, alone or in combination with the MEK inhibitor, trametinib. This study aimed to elucidate the involvement of EVs in MM progression and ascertain whether EV-mediated metastasis promotion persists during single agent BRAF (vemurafenib, dabrafenib), or MEK (trametinib) and combined BRAF/MEK (dabrafenib/trametinib) inhibition.Using five pairs of syngeneic melanoma cell lines, we assessed the impact of EVs - isolated from their respective supernatants - on melanoma cell proliferation and migration. Cell viability and spheroid growth assays were employed to evaluate proliferation, while migration was analyzed through mean squared displacement (MSD) and total traveled distance (TTD) measurements derived from video microscopy and single-cell tracking.Our results indicate that while EV treatments had remarkable promoting effect on cell migration, they exerted only a modest effect on cell proliferation and spheroid growth. Notably, EVs demonstrated the ability to mitigate the inhibitory effects of BRAF inhibitors, albeit they were ineffective against a MEK inhibitor and the combination of BRAF/MEK inhibitors. In summary, our findings contribute to the understanding of the intricate role played by EVs in tumor progression, metastasis, and drug resistance in MM.

ALDH1A1 confers resistance to RAF/MEK inhibitors in melanoma cells by maintaining stemness phenotype and activating PI3K/AKT signaling.

The mitogen-activated protein kinase (MAPK/ERK) pathway is pivotal in controlling the proliferation and survival of melanoma cells. Several mutations, including those in BRAF, exhibit an oncogenic effect leading to increased cellular proliferation. As a result, the combination therapy of a MEK inhibitor with a BRAF inhibitor demonstrated higher efficacy and lower toxicity than BRAF inhibitor alone. This combination has become the preferred standard of care for tumors driven by BRAF mutations. Aldehyde dehydrogenase 1A1 (ALDH1A1) is a known marker of stemness involved in drug resistance in several type of tumors, including melanoma. This study demonstrates that melanoma cells overexpressing ALDH1A1 displayed resistance to vemurafenib and trametinib through the activation of PI3K/AKT signaling instead of MAPK axis. Inhibition of PI3K/AKT signaling partially rescued sensitivity to the drugs. Consistently, pharmacological inhibition of ALDH1A1 activity downregulated the activation of AKT and partially recovered responsiveness to vemurafenib and trametinib. We propose ALDH1A1 as a new potential target for treating melanoma resistant to MAPK/ERK inhibitors.

Correlation between the dynamic changes of γδT cells, Th17 cells, CD4+CD25+ regulatory T cells in peripheral blood and pharmacological interventions against bleomycin-induced pulmonary fibrosis progression in mice.

The involvement of γδT cells, Th17 cells, and CD4+CD25+ regulatory T cells (Tregs) is crucial in the progression of pulmonary fibrosis (PF), particularly in maintaining immune tolerance and homeostasis. However, the dynamics of these cells in relation to PF progression, especially under pharmacological interventions, remains poorly understood. This study aims to unravel the interplay between the dynamic changes of these cells and the effect of pharmacological agents in a mouse model of PF induced by intratracheal instillation of bleomycin. We analyzed changes in lung histology, lung index, hydroxyproline levels, and the proportions of γδT cells, Th17 cells, and Tregs on the 3rd, 14th, and 28th days following treatment with Neferine, Isoliensinine, Pirfenidone, and Prednisolone. Our results demonstrate that these drugs can partially or dynamically reverse weight loss, decrease lung index and hydroxyproline levels, and ameliorate lung histopathological damage. Additionally, they significantly modulated the abnormal changes in γδT, Th17, and Treg cell proportions. Notably, on day 3, the proportion of γδT cells increased in the Neferine and Prednisolone groups but decreased in the Isoliensinine and Pirfenidone groups, while the proportion of Th17 cells decreased across all treated groups. On day 14, the Neferine group showed an increase in all three cell types, whereas the Pirfenidone group exhibited a decrease. In the Isoliensinine group, γδT and Th17 cells increased, and in the Prednisolone group, only Tregs increased. By day 28, an increase in Th17 cell proportion was observed in all treatment groups, with a decrease in γδT cells noted in the Neferine group. These shifts in cell proportions are consistent with the pathogenesis changes induced by these anti-PF drugs, suggesting a correlation between cellular dynamics and pharmacological interventions in PF progression. Our findings imply potential strategies for assessing the efficacy and timing of anti-PF treatments based on these cellular changes.

2,2- dimethylbenzopyran derivatives containing pyridone structural fragments as selective dual-targeting inhibitors of HIF-1α and EZH2 for the treatment of lung cancer.

We formerly reported that EZH2 inhibitors sensitized HIF-1 inhibitor-resistant cells and inhibited HIF-1α to promote SUZ12 transcription, leading to enhanced EZH2 enzyme activity and elevated H3K27me3 levels, and conversely, inhibition of EZH2 promoted HIF-1α transcription. HIF-1α and EZH2 interacted to form a negative feedback loop that reinforced each other's activity. In this paper, a series of 2,2- dimethylbenzopyran derivatives containing pyridone structural fragments were designed and synthesized with DYB-03, a HIF-1α inhibitor previously reported by our group, and Tazemetostat, an EZH2 inhibitor approved by FDA, as lead compounds. Among these compounds, D-01 had significant inhibitory activities on HIF-1α and EZH2. In vitro experiments showed that D-01 significantly inhibited the migration of A549 cells, clone, invasion and angiogenesis. Moreover, D-01 had good pharmacokinetic profiles. All the results about compound D-01 could lay a foundation for the research and development of HIF-1α and EZH2 dual-targeting compounds.

Hyaluronic acid modified extracellular vesicles targeting hepatic stellate cells to attenuate hepatic fibrosis.

RATIONALE: Transforming growth factor-beta1 (TGF-ß1) plays a pivotal role in promoting hepatic fibrosis, pirfenidone (PFD) could inhibit TGF-ß1 signaling pathway to alleviate hepatic stellate cells (HSC) activation mediated hepatic fibrosis. The targeting delivery strategy of PFD to hepatic stellate cells is a challenge. Extracellular vesicles (EVs), cell-derived membranous particles are intraluminal nano-vesicles that play a vital role in intercellular communication, they also be considered as an ideal nano-carrier. METHODS: In this study, we developed a target strategy to deliver PFD to HSC with CD44 over-expression by EVs, hyaluronic acid (HA) modified DSPE-PEG2000 endows the active targeting ability of activated HSCs to PFD-loaded EVs. RESULTS: In both rat hepatic stellate cell line HSC-T6 and rat hepatocyte cell line BRL, HA@EVs-PFD demonstrated the capacity to down-regulate the expression of collagen-synthesis-related proteins and showed superior inhibition efficacy of HSC-T6 activation compared to free PFD. In hepatic fibrosis model, 4 weeks of HA@EVs-PFD treatment resulted in a reduction in liver collagen fibers, significant improvement in hepatic cell morphology, and amelioration of hepatic fibrosis. CONCLUSIONS: HA@EVs-PFD, as a drug delivery system that effectively targets and inhibits activated HSCs to treat hepatic fibrosis, holds promise as a potential therapeutic agent against hepatic fibrosis.

Anti-Xa Monitoring of Apixaban (ZyQuis) in Venous Thrombo-Embolism and Atrial Fibrillation.

Apixaban is a direct oral Xa inhibitor and is indicated for the treatment of venous thrombo-embolism (VTE) and prevention of stroke in atrial fibrillation (AF). Recently, a generic (ZyQuis, Zydus Lifesciences Limited, India) has received Food and Drug Administration approval. While bioequivalence has been demonstrated with Eliquis (Bristol-Myers Squibb/Pfizer, UK), it is necessary to monitor its effectiveness prior to acceptance in medical practice. This prospective study independently evaluated Apixaban (ZyQuis) at two accredited laboratories. Participants were converted from Warfarin or Rivaroxaban to Apixaban 5 mg bd for a duration of one month. Peak anti-Xa levels were measured 3-4 h post the morning dose. The samples were processed on the Atellica COAG 360 (Siemens Healthineers, Marburg, Germany) analyzers with a chromogenic anti-Xa assay (Innovance, reference interval 69-321 ng/mL). There were 26 participants; 5 men, 21 women; mean ± standard deviation age of 46 ± 12 years. Indications for anticoagulation included: VTE (88.5%) and AF (11.5%). 69.2% of the participants had at least one comorbidity. 96.2% of the anti-Xa levels were within the laboratory's 95% reference interval. Mean anti-Xa activity was 191 ± 69 ng/mL and 186 ± 68 ng/mL measured at respective laboratories. Mean differences in anti-Xa measurements represented by Bland-Altman statistics were small (bias of -2.6%, 95% confidence interval -1.11 to -4.09) and a strong correlation was observed on Deming regression analysis (0.995). Apixaban (ZyQuis) was effective for the management of VTE and AF as evidenced by anti-Xa activity.

Discovery of Dolutegravir Derivative against Liver Cancer via Inducing Autophagy and DNA Damage.

We introduced a terminal alkyne into the core structure of dolutegravir, resulting in the synthesis of 34 novel dolutegravir-1,2,3-triazole compounds through click chemistry. These compounds exhibited remarkable inhibitory activities against two hepatocellular carcinoma cell lines, Huh7 and HepG2. Notably, compounds 5e and 5p demonstrated exceptional efficacy, particularly against Huh7 cells, with IC50 values of 2.64 and 5.42 µM. Additionally, both compounds induced apoptosis in Huh7 cells, suppressed tumor cell clone formation, and elevated reactive oxygen species (ROS) levels, further promoting tumor cell apoptosis. Furthermore, compounds 5e and 5p activated the LC3 signaling pathway, inducing autophagy, and triggered the γ-H2AX signaling pathway, resulting in DNA damage in tumor cells. Compound 5e exhibited low toxicity, highlighting its potential as a promising anti-tumor drug.

Pirfenidone and nintedanib attenuates pulmonary artery endothelial and smooth muscle cells transformations induced by IL-11.

Idiopathic pulmonary fibrosis (IPF) associated to pulmonary hypertension (PH) portends a poor prognosis, characterized by lung parenchyma fibrosis and pulmonary artery remodeling. Serum and parenchyma levels of Interleukin 11 (IL-11) are elevated in IPF-PH patients and contributes to pulmonary artery remodeling and PH. However, the effect of current approved therapies against IPF in pulmonary artery remodeling induced by IL-11 is unknown. The aim of this study is to analyze the effects of nintedanib and pirfenidone on pulmonary artery endothelial and smooth muscle cell remodeling induced by IL-11 in vitro. Our results show that nintedanib (NTD) and pirfenidone (PFD) ameliorates endothelial to mesenchymal transition (EnMT), pulmonary artery smooth muscle cell to myofibroblast-like transformation and pulmonary remodeling in precision lung cut slices. This study provided also evidence of the inhibitory effect of PFD and NTD on IL-11-induced endothelial and muscle cells proliferation and senescence. The inhibitory effect of these drugs on monocyte arrest and angiogenesis was also studied. Finally, we observed that IL-11 induced canonical signal transducer and activator of transcription 3 (STAT3) and non-canonical mitogen-activated protein kinase 1/2 (ERK1/2) phosphorylation, but, PFD and NTD only inhibited ERK1/2 phosphorylation. Therefore, this study provided evidence of the inhibitory effect of NTD and PFD on markers of pulmonary artery remodeling induced by IL-11.

Influenza C virus susceptibility to antivirals with different mechanisms of action.

Antiviral susceptibility of influenza viruses was assessed using a high-content imaging-based neutralization test. Cap-dependent endonuclease inhibitors, baloxavir and AV5116, were superior to AV5115 against type A viruses, and AV5116 was most effective against PA mutants tested. However, these three inhibitors displayed comparable activity (EC50 8-22 nM) against type C viruses from six lineages. Banana lectin and a monoclonal antibody, YA3, targeting the hemagglutinin-esterase protein effectively neutralized some, but not all, type C viruses.

Photodynamic anticancer activity evaluation of novel 5-aminolevulinic acid and 3-hydroxypyridinone conjugates.

5-Aminolevulinic acid (ALA) and its derivatives, serving as the endogenous precursor of the photosensitizer (PS) protoporphyrin IX (PpIX), successfully applied in tumor imaging and photodynamic therapy (PDT). ALA and its derivatives have been used to treat actinic keratosis (AK), basal cell carcinoma (BCC), and improve the detection of superficial bladder cancer. However, the high hydrophilicity of ALA and the conversion of PpIX to heme have limited the accumulation of PpIX, hindering the efficiency and potential application of ALA-PDT. This study aims to evaluate the PDT activity of three rationally designed series of ALA-HPO prodrugs, which were based on enhancing the lipophilicity of the prodrugs and reducing the labile iron pool (LIP) through HPO iron chelators to promote PpIX accumulation. Twenty-four ALA-HPO conjugates, incorporating amide, amino acid, and ester linkages, were synthesized. Most of the conjugates, exhibited no dark-toxicity to cells, according to bioactivity evaluation. Ester conjugates 19a-g showed promoted phototoxicity when tested on tumor cell lines, and this increased phototoxicity was strongly correlated with elevated PpIX levels. Among them, conjugate 19c emerged as the most promising (HeLa, IC50 = 24.25 ± 1.43 µM; MCF-7, IC50 = 43.30 ± 1.76 µM; A375, IC50 = 28.03 ± 1.00 µM), displaying superior photodynamic anticancer activity to ALA (IC50 > 100 µM). At a concentration of 80 µM, the fluorescence intensity of PpIX induced by compound 19c in HeLa, MCF-7, and A375 cells was 18.9, 5.3, and 2.8 times higher, respectively, than that induced by ALA. In conclusion, cellular phototoxicity showed a strong correlation with intracellular PpIX fluorescence levels, indicating the potential application of ALA-HPO conjugates in ALA-PDT.

Discovery of novel pyridone-benzamide derivatives possessing a 1-methyl-2-benzimidazolinone moiety as potent EZH2 inhibitors for the treatment of B-cell lymphomas.

Enhancer of zeste homolog 2 (EZH2) is a promising therapeutic target for diffuse large B-cell lymphoma. In this study, based on the binding model of 1 (tazemetostat) with polycomb repressive complex 2 (PRC2), we designed and synthesized a series of tazemetostat analogs bearing a 1-methyl-2-benzimidazolinone moiety to improve the inhibitory activity of EZH2 wild-type (WT) and Y641 mutants and enhance metabolic stability. After the assessment of the structure-activity relationship at enzymatic and cellular levels, compound N40 was identified. Biochemical assays showed that compound N40 (IC50 = 0.32 nM) exhibited superior inhibitory activity against EZH2 WT, compared with 1 (IC50 = 1.20 nM), and high potency against EZH2 Y641 mutants (EZH2 Y641F, IC50 = 0.03 nM; EZH2 Y641N, IC50 = 0.08 nM), which were approximately 10-fold more active than those of 1 (EZH2 Y641F, IC50 = 0.37 nM; EZH2 Y641N, IC50 = 0.85 nM). Furthermore, compound N40 (IC50 = 3.52 ±â€¯1.23 nM) effectively inhibited the proliferation of Karpas-422 cells and was more potent than 1 (IC50 = 35.01 ±â€¯1.28 nM). Further cellular experiments showed that N40 arrested Karpas-422 cells in the G1 phase and induced apoptosis in a dose-dependent manner. Moreover, N40 inhibited the trimethylation of lysine 27 on histone H3 (H3K27Me3) in Karpas-422 cells bearing the EZH2 Y641N mutant. Additionally, N40 (T1/2 = 177.69 min) showed improved metabolic stability in human liver microsomes compared with 1 (T1/2 = 7.97 min). Our findings suggest N40 as a promising EZH2 inhibitor; further investigation remains warranted to confirm our findings and further develop N40.

Narazaciclib, a novel multi-kinase inhibitor with potent activity against CSF1R, FLT3 and CDK6, shows strong anti-AML activity in defined preclinical models.

CSF1R is a receptor tyrosine kinase responsible for the growth/survival/polarization of macrophages and overexpressed in some AML patients. We hypothesized that a novel multi-kinase inhibitor (TKi), narazaciclib (HX301/ON123300), with high potency against CSF1R (IC50 ~ 0.285 nM), would have anti-AML effects. We tested this by confirming HX301's high potency against CSF1R (IC50 ~ 0.285 nM), as well as other kinases, e.g. FLT3 (IC50 of ~ 19.77 nM) and CDK6 (0.53 nM). An in vitro proliferation assay showed that narazaciclib has a high growth inhibitory effect in cell cultures where CSF1R or mutant FLT3-ITD variants that may be proliferation drivers, including primary macrophages (IC50 of 72.5 nM) and a subset of AML lines (IC50 < 1.5 µM). In vivo pharmacology modeling of narazaciclib using five AML xenografts resulted in: inhibition of MV4-11 (FLT3-ITD) subcutaneous tumor growth and complete suppression of AM7577-PDX (FLT3-ITD/CSF1Rmed) systemic growth, likely due to the suppression of FLT3-ITD activity; complete suppression of AM8096-PDX (CSF1Rhi/wild-type FLT3) growth, likely due to the inhibition of CSF1R ("a putative driver"); and nonresponse of both AM5512-PDX and AM7407-PDX (wild-type FLT3/CSF1Rlo). Significant leukemia load reductions in bone marrow, where disease originated, were also achieved in both responders (AM7577/AM8096), implicating that HX301 might be a potentially more effective therapy than those only affecting peripheral leukemic cells. Altogether, narazaciclib can potentially be a candidate treatment for a subset of AML with CSF1Rhi and/or mutant FLT3-ITD variants, particularly second generation FLT3 inhibitor resistant variants.

d-mannose targets PD-1 to lysosomal degradation and enhances T cell-mediated anti-tumor immunity.

High expression of programmed cell death protein 1 (PD-1), a typical immune checkpoint, results in dysfunction of T cells in tumor microenvironment. Antibodies and inhibitors against PD-1 or its ligand (PD-L1) have been widely used in various malignant tumors. However, the mechanisms by which PD-1 is regulated are not fully understood. Here, we report a mechanism of PD-1 degradation triggered by d-mannose and the universality of this mechanism in anti-tumor immunity. We show that d-mannose inactivates GSK3ß via promoting phosphorylation of GSK3ß at Ser9, thereby leading to TFE3 translocation to nucleus and subsequent PD-1 proteolysis induced by enhanced lysosome biogenesis. Notably, combination of d-mannose and PD-1 blockade exhibits remarkable tumor growth suppression attributed to elevated cytotoxicity activity of T cells in vivo. Furthermore, d-mannose treatment dramatically improves the therapeutic efficacy of MEK inhibitor (MEKi) trametinib in vivo. Our findings unveil a universally unrecognized anti-tumor mechanism of d-mannose by destabilizing PD-1 and provide strategies to enhance the efficacy of both immune checkpoint blockade (ICB) and MEKi -based therapies.

Shengxian decoction improves lung function in rats with bleomycin-induced idiopathic pulmonary fibrosis through the inhibition of PANoptosis.

ETHNOPHARMACOLOGICAL RELEVANCE: Shengxian decoction (SXD) is a classic Chinese medicinal formula that can effectively improve clinical symptoms and quality of life and delay disease progression in idiopathic pulmonary fibrosis (IPF) patients; however, the underlying mechanisms remain unclear. AIM OF THE STUDY: This study aimed to observe PANoptosis in bleomycin-induced IPF and to assess the efficacy and mechanism of action of SXD in the treatment of IPF. MATERIALS AND METHODS: Fifty SD rats were randomly divided into the sham, IPF, IPF + pirfenidone (PFD), IPF + SXD-medium dose (SXD-M), and IPF + SXD-low dose (SXD-L) groups. Lung function analysis and microcomputed tomography imaging of the rats with IPF treated with oral pirfenidone or oral SXD for 28 days were performed. Hematoxylin and eosin (HE) staining and Masson's trichrome staining were used to observe pathological lung damage. Enzyme-linked immunosorbent assays (ELISAs) were used to determine the serum levels of IL-1ß, IL-18, TNF-α, and IFN-γ. Pyroptosis, apoptosis, and necroptosis were assessed using TUNEL, TUNEL/caspase-1, and PI fluorescence staining, respectively. GSDMD, caspase-3, and MLKL were examined by immunohistochemistry. The expression of fibrin-, ZBP1-, pyroptosis-, apoptosis-, and necroptosis-related proteins in the lung tissue was determined by western blotting. RESULTS: SXD normalized lung function in rats with bleomycin-induced IPF and reduced serum inflammatory factor levels and lung tissue fibrosis. The underlying mechanism of action involves the inhibition of pyroptosis pathway proteins, such as NLRP3, caspase-1, cleaved caspase-1, and GSDMD; apoptotic pathway proteins, such as Bax, Bcl-2, cleaved caspase-3, and caspase-3; and necroptosis pathway proteins, such as RIPK1, RIPK3, p-MLKL and MLKL. These pathways are modulated by the PANoptosis initiator ZBP1. Notably, the efficacy of SXD is concentration dependent, with a medium dose exhibiting superior effectiveness compared to a low dose. CONCLUSION: Bleomycin induced PANoptosis in the lung tissue of rats with IPF. Additionally, SXD effectively delayed or reversed the early pathological changes in bleomycin-induced pulmonary fibrosis by inhibiting PANoptosis.