Dissolving microneedles loaded with nimodipine for prevention of sleep disorders at a high altitude.

Sleep disorders are one of the most common acute reactions on the plateau, which can cause serious complications. However, there is no effective and safe treatment currently available. Nimodipine (NMD) is a dihydropyridine calcium channel blocker with neuroprotective and vasodilating activity, mainly used for the treatment of ischemic brain injury. Commercial oral or injectable NMD formulations are not a good option for central neuron diseases due to their poor brain delivery. In this study, nimodipine dissolving microneedles (NDMNs) were prepared for the prevention of sleep disorders caused by hypoxia. NDMNs were composed of NMD and polyvinyl pyrrolidone (PVP) K90 with a conical morphology and high rigidity. After administration of NDMNs on the back neck of mice, the concentration of NMD in the brain was significantly higher than that of oral medication as was confirmed by the fluorescent imaging on mouse models. NDMNs enhanced cognitive function, alleviated oxidative stress, and improved the sleep quality of mice with high-altitude sleep disorders. The blockage of calcium ion overloading may be an important modulation mechanism. NDMNs are a promising and user-friendly formulation for the prevention of high-altitude sleep disorders.

Prediction of Human Pharmacokinetics of E0703, a Novel Radioprotective Agent, Using Physiologically Based Pharmacokinetic Modeling and an Interspecies Extrapolation Approach.

E0703, a new steroidal compound optimized from estradiol, significantly increased cell proliferation and the survival rate of KM mice and beagles after ionizing radiation. In this study, we characterize its preclinical pharmacokinetics (PK) and predict its human PK using a physiologically based pharmacokinetic (PBPK) model. The preclinical PK of E0703 was studied in mice and Rhesus monkeys. Asian human clearance (CL) values for E0703 were predicted from various allometric methods. The human PK profiles of E0703 (30 mg) were predicted by the PBPK model in Gastro Plus software 9.8 (SimulationsPlus, Lancaster, CA, USA). Furthermore, tissue distribution and the human PK profiles of different administration dosages and forms were predicted. The 0.002 L/h of CL and 0.005 L of Vss in mice were calculated and optimized from observed PK data. The plasma exposure of E0703 was availably predicted by the CL using the simple allometry (SA) method. The plasma concentration-time profiles of other dosages (20 and 40 mg) and two oral administrations (30 mg) were well-fitted to the observed values. In addition, the PK profile of target organs for E0703 exhibited a higher peak concentration (Cmax) and AUC than plasma. The developed E0703-PBPK model, which is precisely applicable to multiple species, benefits from further clinical development to predict PK in humans.

Exosome circATP8A1 induces macrophage M2 polarization by regulating the miR-1-3p/STAT6 axis to promote gastric cancer progression.

Circular RNAs (circRNAs) play important roles in gastric cancer progression but the regulatory role of circRNAs in controlling macrophage function remains elusive. Exosomes serve as cargo for circRNAs and play a crucial role as mediators in facilitating communication between cancer cells and the tumor microenvironment. In this study, we found that circATP8A1, a previously unreported circular RNA, is highly expressed in both gastric cancer tissues and exosomes derived from plasma. Increased circATP8A1 was associated with advanced TNM stage and worse prognosis in patients with gastric cancer. We showed that  the circATP8A1 knockdown significantly inhibited gastric cancer proliferation and invasion in vitro and in vivo. Functionally, exosome circATP8A1 induced the M2 polarization of macrophages through the STAT6 pathway instead of the STAT3 pathway. Mechanistically, circATP8A1 was shown to activate the STAT6 pathway through competitive binding to miR-1-3p, as confirmed by Fluorescence In Situ Hybridization (FISH), RNA immunoprecipitation, RNA pulldown, and Luciferase reporter assays. The reversal of circATP8A1-induced STAT6 pathway activation and macrophage polarization was observed upon blocking miR-1-3p. Macrophages treated with exosomes from gastric cancer cells overexpressing circATP8A1 were able to promote gastric cancer migration, while knockdown of circATP8A1 reversed these effects in vivo. In summary, exosome-derived circATP8A1 from gastric cancer cells induce macrophages M2 polarization via the circATP8A1/miR-1-3p/STAT6 axis, and tumor progression. Our results highlight circATP8A1 as a potential prognostic biomarker and therapeutic target in gastric cancer.

Simultaneous determination of HD56, a novel prodrug, and its active metabolite in cynomolgus monkey plasma using LC-MS/MS for elucidating its pharmacokinetic profile.

An LC-MS/MS method was developed and validated for the simultaneous determination of the carboxylic acid ester precursor HD56 and the active product HD561 in cynomolgus monkey plasma. Then, the pharmacokinetic characteristics of both compounds following single and multiple i.g. administrations in cynomolgus monkeys were elucidated. In the method, chromatographic separation was achieved with a C18 reversed-phase column and the target quantification was carried out by an electrospray ionization (ESI) source coupled with triple quadrupole mess detector in positive ionization mode with multiple reaction monitoring (MRM) approach. Using the quantification method, the in vitro stability of HD56 in plasma and HD56 pharmacokinetic behavior after i.g. administration in cynomolgus monkey were investigated. It was approved that HD56 did convert into HD561 post-administration. The overall systemic exposure of HD561 post-conversion from HD56 accounted for only about 17% of HD56. After repeated administration at the same dose, there was no significant difference in exposure levels of both HD56 and HD561. However, after multiple dosing, the exposure of HD56 tended to decrease while that of HD561 tended to increase, resulting in a 30% in the exposure ratio. Remarkably, with a carboxylesterase (CES) activity profile akin to humans, the observed in vivo pharmacokinetic profile in cynomolgus monkeys holds promise for predicting HD56/HD561 PK profiles in humans.

Coadministration of bedaquiline and pyrifazimine reduce exposure to toxic metabolite N-desmethyl bedaquiline.

Background: A new, effective anti-tuberculosis (TB) regimen containing bedaquiline (BDQ) and pyrifazimine (TBI-166) has been recommended for a phase IIb clinical trial. Preclinical drug-drug interaction (DDI) studies of the combination of BDQ and TBI-166 have been designed to support future clinical trials. In this study, we investigated whether a DDI between BDQ and TBI-166 affects the pharmacokinetics of BDQ. Methods: We performed in vitro quantification of the fractional contributions of the fraction of drug metabolism by individual CYP enzymes (f m) of BDQ and the inhibition potency of key metabolic pathways of TBI-166. Furthermore, we conducted an in vivo steady-state pharmacokinetics study in a murine TB model and healthy BALB/c mice. Results: The in vitro f m value indicated that the CYP3A4 pathway contributed more than 75% to BDQ metabolism to N-desmethyl-bedaquiline (M2), and TBI-166 was a moderate (IC50 2.65 µM) potential CYP3A4 inhibitor. Coadministration of BDQ and TBI-166 greatly reduced exposure to metabolite M2 (AUC0-t 76310 vs 115704 h ng/mL, 66% of BDQ alone), whereas the exposure to BDQ and TBI-166 did not changed. The same trend was observed both in healthy and TB model mice. The plasma concentration of M2 decreased significantly after coadministration of BDQ and TBI-166 and decreased further during treatment in the TB model. Conclusions: In conclusion, our results showed that the combination of BDQ and TBI-166 significantly reduced exposure to the toxic metabolite M2 by inhibiting the activity of the CYP3A4 pathway. The potential safety and efficacy benefits demonstrated by the TB treatment highly suggest that coadministration of BDQ and TBI-166 should be studied further.

miR-221/222 induce instability of p53 By downregulating deubiquitinase YOD1 in acute myeloid leukemia.

Acute myeloid leukemia (AML) is a hematological malignancy characterized by the impaired differentiation and uncontrolled proliferation of myeloid blasts. Tumor suppressor p53 is often downregulated in AML cells via ubiquitination-mediated degradation. While the role of E3 ligase MDM2 in p53 ubiquitination is well-accepted, little is known about the involvement of deubiquitinases (DUBs). Herein, we found that the expression of YOD1, among several DUBs, is substantially reduced in blood cells from AML patients. We identified that YOD1 deubiqutinated and stabilized p53 through interaction via N-terminus of p53 and OTU domain of YOD1. In addition, expression levels of YOD1 were suppressed by elevated miR-221/222 in AML cells through binding to the 3' untranslated region of YOD1, as verified by reporter gene assays. Treatment of cells with miR-221/222 mimics and inhibitors yielded the expected effects on YOD1 expressions, in agreement with the negative correlation observed between the expression levels of miR-221/222 and YOD1 in AML cells. Finally, overexpression of YOD1 stabilized p53, upregulated pro-apoptotic p53 downstream genes, and increased the sensitivity of AML cells to FLT3 inhibitors remarkably. Collectively, our study identified a pathway connecting miR-221/222, YOD1, and p53 in AML. Targeting miR-221/222 and stimulating YOD1 activity may improve the therapeutic effects of FLT3 inhibitors in patients with AML.

Discovery of novel exceptionally potent and orally active c-MET PROTACs for the treatment of tumors with MET alterations.

Various c-mesenchymal-to-epithelial transition (c-MET) inhibitors are effective in the treatment of non-small cell lung cancer; however, the inevitable drug resistance remains a challenge, limiting their clinical efficacy. Therefore, novel strategies targeting c-MET are urgently required. Herein, through rational structure optimization, we obtained novel exceptionally potent and orally active c-MET proteolysis targeting chimeras (PROTACs) namely D10 and D15 based on thalidomide and tepotinib. D10 and D15 inhibited cell growth with low nanomolar IC50 values and achieved picomolar DC50 values and >99% of maximum degradation (Dmax) in EBC-1 and Hs746T cells. Mechanistically, D10 and D15 dramatically induced cell apoptosis, G1 cell cycle arrest and inhibited cell migration and invasion. Notably, intraperitoneal administration of D10 and D15 significantly inhibited tumor growth in the EBC-1 xenograft model and oral administration of D15 induced approximately complete tumor suppression in the Hs746T xenograft model with well-tolerated dose-schedules. Furthermore, D10 and D15 exerted significant anti-tumor effect in cells with c-METY1230H and c-METD1228N mutations, which are resistant to tepotinib in clinic. These findings demonstrated that D10 and D15 could serve as candidates for the treatment of tumors with MET alterations.

An exploration on retro-construction of plasma drug concentration-time curves from corresponding urine excretion data and single-point plasma concentrations using a simplified and idealized method.

Background: Despite the availability of various tools of modeling and simulation, clinical pediatric pharmacokinetic (PK) studies remain far less efficient than those on adults due to ethical constraints. One of the optimal solutions is to substitute urine to blood sampling based on explicit mathematic relationships between them. However, this idea is limited by three main knowledge gaps associated with urine data, i.e., complicated excretion equations with excessive parameters, insufficient frequency that is hard to fit, and the mere expression of amounts with no in vivo distribution volume information involved. Methods: To overcome these obstacles, we sacrificed the precision from mechanistic PK models with complex excretion equations to expediency of compartmental model in which a constant ke is used to cover all the internal parameters. And the total cumulative amounts of urinary drug excretion (Xu∞) were estimated and introduced to the excretion equation so that urine data were likely to be fitted using a semi-log-terminal linear regression method. In addition, urinary excretion clearance (CLr) could be calculated by single point plasma data to anchor the plasma concentration-time (C-t) curve based on the assumption that CLr was kept constant throughout the PK process. Results: After sensitivity analysis of two subjective judgements (the selection of the compartmental model and the selection of plasma time point to calculate CLr), the performance of the optimized models was assessed using desloratadine or busulfan as model drugs in a variety of PK scenarios, from i.v. bolus/infusion to p.o. administration, from a single dose to multiple doses, and from rats to children. The fitting plasma drug concentrations of the optimal model were close to the observed value. Meanwhile, the drawbacks inherent to the simplified and idealized modeling strategy were fully identified. Conclusions: The method proposed by this tentative proof-of-principle study was able to deliver acceptable plasma exposure curves and shed light on the future refinements.

Host-Guest Formulation of Carboxylatopillar[6]arene with Ergothioneine as a New Antidote for Combinational Detoxification of Paraquat.

Paraquat (PQ) is exceptionally toxic to the human body. PQ ingestion can cause severe organ damage with a mortality rate of 50-80%, resulting from the absence of effective antidotes and detoxification solutions. Herein, a host-guest formulation is proposed, in which ergothioneine (EGT), an antioxidant drug, was encapsulated by carboxylatopillar[6]arene (CP6A) to achieve a combinational therapy for PQ poisoning. Nuclear magnetic resonance (NMR) and fluorescence titration were employed to confirm the complexation between CP6A and EGT as well as PQ with robust affinities. In vitro studies proved that EGT/CP6A significantly reduced PQ toxicity. Treatment with EGT/CP6A could effectively relieve organ damage caused by PQ ingestion and enhance the normalization of hematological and biochemical parameters. The host-guest formulation EGT/CP6A also improved the survival ratio in PQ-poisoned mice. These favorable outcomes originated from synergistic effects that PQ triggered the release of EGT to combat peroxidation damage and excess PQ was engulfed within the cavity of CP6A.

Recent advances of three-dimensional bioprinting technology in hepato-pancreato-biliary cancer models.

Hepato-pancreato-biliary (HPB) cancer is a serious category of cancer including tumors originating in the liver, pancreas, gallbladder and biliary ducts. It is limited by two-dimensional (2D) cell culture models for studying its complicated tumor microenvironment including diverse contents and dynamic nature. Recently developed three-dimensional (3D) bioprinting is a state-of-the-art technology for fabrication of biological constructs through layer-by-layer deposition of bioinks in a spatially defined manner, which is computer-aided and designed to generate viable 3D constructs. 3D bioprinting has the potential to more closely recapitulate the tumor microenvironment, dynamic and complex cell-cell and cell-matrix interactions compared to the current methods, which benefits from its precise definition of positioning of various cell types and perfusing network in a high-throughput manner. In this review, we introduce and compare multiple types of 3D bioprinting methodologies for HPB cancer and other digestive tumors. We discuss the progress and application of 3D bioprinting in HPB and gastrointestinal cancers, focusing on tumor model manufacturing. We also highlight the current challenges regarding clinical translation of 3D bioprinting and bioinks in the field of digestive tumor research. Finally, we suggest valuable perspectives for this advanced technology, including combination of 3D bioprinting with microfluidics and application of 3D bioprinting in the field of tumor immunology.

Combined contributions of cytochrome P450s (CYPs) and non-enzymatic metabolism in the in vitro biotransformation of anaprazole, a novel proton pump inhibitor.

Anaprazole, a new proton pump inhibitor (PPI), is designed for the treatment of acid-related diseases, such as gastric ulcers and gastroesophageal reflux. This study explored the in vitro metabolic transformation of anaprazole. The metabolic stabilities of anaprazole in human plasma and human liver microsomes (HLM) were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Then, the contribution (%) of non-enzymatic and cytochrome P450s (CYPs) enzyme-mediated anaprazole metabolism was assessed. To obtain the metabolic pathways of anaprazole, the metabolites generated in HLM, thermal deactivated HLM, and cDNA-expressed recombinant CYPs incubation systems were identified by ultra-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (UPLC/Q-TOF-MS). Results showed that anaprazole was very stable in human plasma and unstable in HLM. The contribution (%) of non-enzymatic vs. CYPs enzyme-mediated metabolism was 49% vs. 51%. CYP3A4 was the major enzyme (48.3%), followed by CYP2C9 (17.7%) and CYP2C8 (12.3%), in responsible for the metabolism of anaprazole. Specific chemical inhibitors targeting CYP enzymes notably blocked the metabolic transformation of anaprazole. Six metabolites of anaprazole were identified in the non-enzymatic system, whereas 17 metabolites were generated in HLM. The biotransformation reactions mainly included sulfoxide reduction to thioether, sulfoxide oxidation to sulfone, deoxidation, dehydrogenation, O-dealkylation or O-demethylation of thioether, O-demethylation and dehydrogenation of thioether, O-dealkylation and dehydrogenation of thioether, thioether O-dealkylation and dehydrogenation of thioether, and O-dealkylation of sulfone. Both enzymatic and non-enzymatic metabolisms contribute to the clearance of anaprazole in human. Anaprazole is less likely to develop drug-drug interactions in clinical use compared to other PPIs.

Antiviral effects and tissue exposure of tetrandrine against SARS-CoV-2 infection and COVID-19.

Tetrandrine (TET) has been used to treat silicosis in China for decades. The aim of this study was to facilitate rational repurposing of TET against SARS-CoV-2 infection. In this study, we confirmed that TET exhibited antiviral potency against SARS-CoV-2 in the African green monkey kidney (Vero E6), human hepatocarcinoma (Huh7), and human lung adenocarcinoma epithelial (Calu-3) cell lines. TET functioned during the early-entry stage of SARS-CoV-2 and impeded intracellular trafficking of the virus from early endosomes to endolysosomes. An in vivo study that used adenovirus (AdV) 5-human angiotensin-converting enzyme 2 (hACE2)-transduced mice showed that although TET did not reduce pulmonary viral load, it significantly alleviated pathological damage in SARS-CoV-2-infected murine lungs. The systemic preclinical pharmacokinetics were investigated based on in vivo and in vitro models, and the route-dependent biodistribution of TET was explored. TET had a large volume of distribution, which contributed to its high tissue accumulation. Inhaled administration helped TET target the lung and reduced its exposure to other tissues, which mitigated its off-target toxicity. Based on the available human pharmacokinetic data, it appeared feasible to achieve an unbound TET 90% maximal effective concentration (EC90) in human lungs. This study provides insights into the route-dependent pulmonary biodistribution of TET associated with its efficacy.

Direct chemical induction of hepatocyte-like cells with capacity for liver repopulation.

BACKGROUND AND AIMS: Cell fate can be directly reprogrammed from accessible cell types (e.g., fibroblasts) into functional cell types by exposure to small molecule stimuli. However, no chemical reprogramming method has been reported to date that successfully generates functional hepatocyte-like cells that can repopulate liver tissue, casting doubt over the feasibility of chemical reprogramming approaches to obtain desirable cell types for therapeutic applications. APPROACH AND RESULTS: Here, through chemical induction of phenotypic plasticity, we provide a proof-of-concept demonstration of the direct chemical reprogramming of mouse fibroblasts into functional hepatocyte-like cells using exposure to small molecule cocktails in culture medium to successively stimulate endogenous expression of master transcription factors associated with hepatocyte development, such as hepatocyte nuclear factor 4a, nuclear receptor subfamily 1, group I, member 2, and nuclear receptor subfamily 1, group H, member 4. RNA sequencing analysis, metabolic assays, and in vivo physiological experiments show that chemically induced hepatocytes (CiHeps) exhibit comparable activity and function to primary hepatocytes, especially in liver repopulation to rescue liver failure in fumarylacetoacetate hydrolase -/- recombination activating gene 2 -/- interleukin 2 receptor, gamma chain -/- mice in vivo . Single-cell RNA-seq further revealed that gastrointestinal-like and keratinocyte-like cells were induced along with CiHeps, resembling the activation of an intestinal program within hepatic reprogramming as described in transgenic approaches. CONCLUSIONS: Our findings show that direct chemical reprogramming can generate hepatocyte-like cells with high-quality physiological properties, providing a paradigm for establishing hepatocyte identity in fibroblasts and demonstrating the potential for chemical reprogramming in organ/tissue repair and regeneration therapies.

Development and application of a highly sensitive method for detection of mutation of FMS-like tyrosine kinase-3-tyrosine kinase domain of acute myeloid leukemia / 中国生物制品学杂志

@#ObjectiveTo develop a highly sensitive method for detection of mutation of FMS-like tyrosine kinase-3-tyrosine kinase domain(FLT3-TKD)of acute myeloid leukemia(AML)and apply to the monitor of minimal residual disease(MRD).MethodsRecombinant plasmids containing wild FLT3 and mutant FLT3-D835Y were constructed respectively and mixed at certain ratios.The obtained standard plasmids with mutation rates of 50%,1%,0.1% and 0% respectively were determined by restriction fragment length polymorphism(RFLP)in combination with Sanger method.The plasmid DNA standards and blood DNA standards,at various FLT3-D835Y mutation rates,were determined by the developed method to verify the sensitivity.The genomic DNA samples of patients with AML before and after treatment were determined by the developed method to monitor the MRD.ResultsSequencing proved that both the recombinant plasmids containing wild FLT3 and mutant FLT3-D835Y were constructed correctly.The sensitivity of developed method increased to 0.1% through Sanger method combined with digestion with EcoR Ⅴ/Xho Ⅰ and recovery of mutant fragments in determination of purified plasmid DNA and collected blood DNA samples.MRD was detected in the peripheral blood sample of a patients with AML in complete remission period by the developed method but not by Sanger method.ConclusionA highly sensitive method for detection of FLT3-TKD mutation was developed,which was of an important clinical significance in guiding the treatment of AML and monitoring the MRD in complete remission period.

Alternation of Organ-Specific Exposure in LPS-Induced Pneumonia Mice after the Inhalation of Tetrandrine Is Governed by Metabolizing Enzyme Suppression and Lysosomal Trapping.

The objective of the present study was to define whether inhaled tetrandrine (TET) could be a promising way to achieve the local effect on its therapeutic efficacy based on biodistribution features using the LPS-treated acute lung injury (ALI) model. The tissue distribution profiles of inhaled TET in normal and ALI mouse models showed that pulmonary inflammation led to an altered distribution in a tissue-specific way. More TET accumulated in almost all tissues including in the blood. Among them, the increased exposure in the lungs was significantly higher than in the other tissues. However, there was a negative increase in the brain. In vitro turnover rates of TET in mouse liver microsomes (MLM) from normal and LPS-treated mice showed significant differences. In the presence of NADPH, TET demonstrated relatively low hepatic clearance (89 mL/h/kg) in that of normal MLM (140 mL/h/kg). Intracellular uptakes of TET in A549, HepG2, RAW264.7, and C8-D1A cells were significantly inhibited by monensin, indicating that the intracellular accumulation of TET is driven by lysosomal trapping. However, in the presence of LPS, only the lysosomal pH partitioning of TET in A549 cell lines increased (~30%). Bidirectional transport of TET across LLC-PK1 cell expressing MDR1 showed that MDR1 is responsible for the low brain exposure via effluxion (ER = 32.46). From the observed overall agreement between the in vitro and in vivo results, we concluded that the downregulation of the CYP3A together with strengthened pulmometry lysosomal trapping magnified the retention of inhaled TET in the lung. These results therefore open the possibility of prolonging the duration of the local anti-inflammation effect against respiratory disorders.

Cinnarizine dissolving microneedles against microwave-induced brain injury.

Microwave is commonly used in the life, manufacturing and military fields, which may induce body injuries. Brain is the major target organ of microwave radiation and microwave-induced brain injury (MIBI) can lead to insomnia, dreaminess, and a decline in learning and memory. However, there is no clinical medications are available currently. Calcium channel blockers may protect the brain tissue from microwave but most of them cannot enter the brain. Here, we selected a calcium channel blocker-cinnarizine to prepare its dissolving microneedles (MNs) for the therapy of MIBI. The cinnarizine MNs was composed of polyvinyl pyrrolidone (PVP) K90 as the tip, the photopolymerized PVP as the base and the drug, which owned high mechanical strength, leading to easily piecing the skin on the neck and high drug release in vivo. The cinnarizine MNs markedly improved the recovery of spatial memory and spontaneous exploratory behavior of the rats after microwave radiation by inhibiting the expression of calcineurin and calpain-1. The dissolving MN technique is a promising method to improve drugs into the body and perform the anti-microwave radiation action.

Translational pharmacokinetics of a novel bispecific antibody against Ebola virus (MBS77E) from animal to human by PBPK modeling & simulation.

The goal of this study was to construct a PBPK model to accelerate the translation of MBS77E, a humanized bispecific antibody against the Ebola virus. In-depth nonclinical pharmacokinetic studies in rats, monkeys, wild-type mice and transgenic mice were conducted. The pH-dependent affinities (KD) of MBS77E to recombinant FcRn of different species were determined by surface plasmon resonance analysis. A mechanistic whole-body PBPK model of MBS77E was developed and validated in the assessment of PK profiles and tissue distributions in preclinical models. This PBPK model was finally used to predict human PK behaviors of MBS77E. Simulations from the PBPK model with measured and fitted parameters were able to yield good predictions of the serum and tissue pharmacokinetic parameters of MBS77E within 2-fold errors. The predicted serum concentration in humans was able to maintain a sufficiently high level for more than 14 days after 50 mg/kg i.v. administrating. This achievement unlocks that PBPK modeling is a powerful tool to gain insights into the properties of antibody drugs. It guided experimental efforts to obtain necessary information before entry into humans.

High-content imaging of human hepatic spheroids for researching the mechanism of duloxetine-induced hepatotoxicity.

Duloxetine (DLX) has been approved for the successful treatment of psychiatric diseases, including major depressive disorder, diabetic neuropathy, fibromyalgia and generalized anxiety disorder. However, since the usage of DLX carries a manufacturer warning of hepatotoxicity given its implication in numerous cases of drug-induced liver injuries (DILI), it is not recommended for patients with chronic liver diseases. In our previous study, we developed an enhanced human-simulated hepatic spheroid (EHS) imaging model system for performing drug hepatotoxicity evaluation using the human hepatoma cell line HepaRG and the support of a pulverized liver biomatrix scaffold, which demonstrated much improved hepatic-specific functions. In the current study, we were able to use this robust model to demonstrate that the DLX-DILI is a human CYP450 specific, metabolism-dependent, oxidative stress triggered complex hepatic injury. High-content imaging analysis (HCA) of organoids exposed to DLX showed that the potential toxicophore, naphthyl ring in DLX initiated oxidative stress which ultimately led to mitochondrial dysfunction in the hepatic organoids, and vice versa. Furthermore, DLX-induced hepatic steatosis and cholestasis was also detected in the exposed EHSs. We also discovered that a novel compound S-071031B, which replaced DLX's naphthyl ring with benzodioxole, showed dramatically lower hepatotoxicities through reducing oxidative stress. Thus, we conclusively present the human-relevant EHS model as an ideal, highly competent system for evaluating DLX induced hepatotoxicity and exploring related mechanisms in vitro. Moreover, HCA use on functional hepatic organoids has promising application prospects for guiding compound structural modifications and optimization in order to improve drug development by reducing hepatotoxicity.

The Molecular Mechanisms of Resistance to IDH Inhibitors in Acute Myeloid Leukemia.

Gain-of-function mutations of isocitrate dehydrogenases 1/2 (IDH1/2) play crucial roles in the development and progression of acute myeloid leukemia (AML), which provide promising therapeutic targets. Two small molecular inhibitors, ivosidenib and enasidenib have been approved for the treatment of IDH1- and IDH2-mutant AML, respectively. Although these inhibitors benefit patients with AML clinically, drug resistance still occurs and have become a major problem for targeted therapies of IDH-mutant AML. A number of up-to-date studies have demonstrated molecular mechanisms of resistance, providing rationales of novel therapeutic strategies targeting mutant IDH1/2. In this review, we discuss mechanisms of resistance to ivosidenib and enasidenib in patients with AML.

Discovery of highly potent and selective CRBN-recruiting EGFRL858R/T790M degraders in vivo.

Currently, epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) are widely used in the treatment of non-small cell lung cancer (NSCLC). However, the inevitable drug resistance and side effects are the current main obstacle, which motivating novel therapies. Proteolysis targeting chimera (PROTAC), a lately-developed technology to target proteins for degradation, has been utilized for drug development. Therefore, we designed, synthesized and evaluated a series of CRBN-recruiting EGFR degraders. Among them, 13a and 13b significantly inhibited NCI-H1975 cells proliferation with IC50 values of 58.08 nM and 46.82 nM, respectively, whereas exhibited more than 100 µM against A549 or H1299 cells, whose selectivity was more than 1700-fold. 13a and 13b potently induced the EGFRL858R/T790M degradation by ubiquitin proteasome system in a time- and dose-dependent manner but not that of EGFRWT, and the DC50 values of 13b was 13.2 nM, which was the most potent compound in current known CRBN-recruiting EGFRL858R/T790M degraders. 13a and 13b dramatically induced cell apoptosis, cell cycle arrest and inhibited downstream signaling pathways. Furthermore, 13a and 13b effectively and selectively inhibited NCI-H1975 xenograft tumor growth with good pharmacokinetics (PK) properties in vivo. These findings demonstrate that 13a and 13b could serve as candidates for developing the drug for treating NSCLC.