Discovery of a Highly Potent PROTAC Degrader of p300/CBP Proteins for the Treatment of Enzalutamide-Resistant Prostate Cancer.

Prostate cancer therapies against androgen receptor (AR) eventually develop lethal resistance; thus, exploring new therapeutic approaches is urgent for prostate cancer treatment. Acetyltransferase p300/CBP are key coactivators for AR-mediated transcription and represent promising therapeutic targets to inhibit AR activity in prostate cancer. We describe the design synthesis and evaluation of a new class of p300/CBP PROTAC degraders. We identified an excellent p300/CBP degrader MJP6412, which effectively induced degradation of p300/CBP proteins, downregulated AR target genes, and inhibited cell growth of human prostate cancer cell lines and enzalutamide-resistant cells with IC50 even at nanomolar concentrations. Furthermore, MJP6412 demonstrated significant inhibition of tumor growth in a VCaP xenograft model. Collectively, MJP6412 is a promising lead compound for the treatment of prostate cancer, especially enzalutamide-resistant prostate cancer.

Baicalin protects against hepatocyte injury caused by aflatoxin B1 via the TP53-related ferroptosis Pathway.

OBJECTIVE: Baicalin has antioxidative, antiviral, and anti-inflammatory properties. However, its ability to alleviate oxidative stress (OS) and DNA damage in liver cells exposed to aflatoxin B1 (AFB1), a highly hepatotoxic compound, remains uncertain. In this study, the protective effects of baicalin on AFB1-induced hepatocyte injury and the mechanisms underlying those effects were investigated. METHODS: Stable cell lines expressing CYP3A4 were established using lentiviral vectors to assess oxidative stress levels by conducting assays to determine the content of reactive oxygen species (ROS), malondialdehyde (MDA), and superoxide dismutase (SOD). Additionally, DNA damage was evaluated by 8-hydroxy-2-deoxyguanosine (8-OHdG) and comet assays. Transcriptome sequencing, molecular docking, and in vitro experiments were conducted to determine the mechanisms underlying the effects of baicalin on AFB1-induced hepatocyte injury. In vivo, a rat model of hepatocyte injury induced by AFB1 was used to evaluate the effects of baicalin. RESULTS: In vitro, baicalin significantly attenuated AFB1-induced injury caused due to OS, as determined by a decrease in ROS, MDA, and SOD levels. Baicalin also considerably decreased AFB1-induced DNA damage in hepatocytes. This protective effect of baicalin was found to be closely associated with the TP53-mediated ferroptosis pathway. To elaborate, baicalin physically interacts with P53, leading to the suppression of the expression of GPX4 and SLC7A11, which in turn inhibits ferroptosis. In vivo findings showed that baicalin decreased DNA damage and ferroptosis in AFB1-treated rat liver tissues, as determined by a decrease in the expression of γ-H2AX and an increase in GPX4 and SLC7A11 levels. Overexpression of TP53 weakened the protective effects of baicalin. CONCLUSIONS: Baicalin can alleviate AFB1-induced OS and DNA damage in liver cells via the TP53-mediated ferroptosis pathway. In this study, a theoretical foundation was established for the use of baicalin in protecting the liver from the toxic effects of AFB1.

Marine Cytotoxin Santacruzamate A Derivatives as Potent HDAC1-3 Inhibitors and Their Synergistic Anti-Leukemia Effects with Venetoclax.

Acute myeloid leukemia (AML) is a hematologic malignancy characterized by infiltration of the blood and bone marrow, exhibiting a low remission rate and high recurrence rate. Current research has demonstrated that class I HDAC inhibitors can downregulate anti-apoptotic proteins, leading to apoptosis of AML cells. In the present investigation, we conducted structural modifications of marine cytotoxin Santacruzamate A (SCA), a compound known for its inhibitory activity towards HDACs, resulting in the development of a novel series of potent class I HDACs hydrazide inhibitors. Representative hydrazide-based compound 25c exhibited concentration-dependent induction of apoptosis in AML cells as a single agent. Moreover, 25c exhibited a synergistic anti-AML effect when combined with Venetoclax, a clinical Bcl-2 inhibitor employed in AML therapy. This combination resulted in a more pronounced downregulation of anti-apoptotic proteins Mcl-1 and Bcl-xL, along with a significant upregulation of the pro-apoptotic protein cleaved-caspase3 and the DNA double-strand break biomarker γ-H2AX compared to monotherapy. These results highlighted the potential of 25c as a promising lead compound for AML treatment, particularly when used in combination with Venetoclax.

Correction: Establishment of a prediction model for prehospital return of spontaneous circulation in out-of-hospital patients with cardiac arrest.

[This corrects the article on p. 508 in vol. 15, PMID: 37900904.].

A Potent SOS1 PROTAC Degrader with Synergistic Efficacy in Combination with KRASG12C Inhibitor.

AMG510, as the first approved inhibitor for KRASG12C mutation, has shown promising efficacy in nonsmall-cell lung cancer and colorectal cancer harboring KRASG12C mutation. However, the moderate response rate and the rapid emergence of acquired resistance limit the therapeutic potential of AMG510, highlighting the need for the development of combination strategies. Here, we observed the suppression of RAS-MAPK signaling induced by AMG510 was prolonged and enhanced by SOS1 knockdown. Thus, we design, synthesize, and characterize a potent and specific SOS1 degrader 23. Compound 23 showed efficient SOS1 degradation in KRAS-driven cancer cells and achieved significant antiproliferative potency. Importantly, the combination of 23 with AMG510 suppressed RAS signaling feedback activation, showing synergistic effects against KRASG12C mutant cells in vitro and in vivo. Our findings demonstrated that KRASG12C inhibition plus SOS1 degradation as a potential therapeutic strategy to improve antitumor response and overcome acquired resistance to KRASG12C inhibitor.

Discovery of Novel 2,3-Dihydro-1H-indene-5-sulfonamide NLRP3 Inflammasome Inhibitors Targeting Colon as a Potential Therapy for Colitis.

The NLRP3 inflammasome is a multiprotein complex that plays a crucial role in the pathophysiology of multiple inflammation-related diseases. In this study, we designed and synthesized a series of novel 2,3-dihydro-1H-indene-5-sulfonamide analogues as NLRP3 inflammasome inhibitors, and then identified compound 15z as a potent and specific inhibitor (IC50: 0.13 µM) with low toxicity. Mechanistic studies indicate that 15z binds directly to NLRP3 protein (KD: 102.7 nM), blocking the assembly and activation of the NLRP3 inflammasome and effectively inhibiting cell pyroptosis. Given the notable distribution of 15z in the colon, the DSS-induced colitis model was employed to evaluate its in vivo effectiveness. 15z significantly impacted NLRP3 inflammasome activation and relieved inflammatory bowel disease symptoms in this model. Acute and subacute toxicity studies suggested that 15z has a favorable safety profile. Our results indicate that 15z has great potential to be further developed as a candidate for the treatment of inflammatory bowel disease.

Establishment of a prediction model for prehospital return of spontaneous circulation in out-of-hospital patients with cardiac arrest.

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) is a leading cause of death worldwide. AIM: To explore factors influencing prehospital return of spontaneous circulation (P-ROSC) in patients with OHCA and develop a nomogram prediction model. METHODS: Clinical data of patients with OHCA in Shenzhen, China, from January 2012 to December 2019 were retrospectively analyzed. Least absolute shrinkage and selection operator (LASSO) regression and multivariate logistic regression were applied to select the optimal factors predicting P-ROSC in patients with OHCA. A nomogram prediction model was established based on these influencing factors. Discrimination and calibration were assessed using receiver operating characteristic (ROC) and calibration curves. Decision curve analysis (DCA) was used to evaluate the model's clinical utility. RESULTS: Among the included 2685 patients with OHCA, the P-ROSC incidence was 5.8%. LASSO and multivariate logistic regression analyses showed that age, bystander cardiopulmonary resuscitation (CPR), initial rhythm, CPR duration, ventilation mode, and pathogenesis were independent factors influencing P-ROSC in these patients. The area under the ROC was 0.963. The calibration plot demonstrated that the predicted P-ROSC model was concordant with the actual P-ROSC. The good clinical usability of the prediction model was confirmed using DCA. CONCLUSION: The nomogram prediction model could effectively predict the probability of P-ROSC in patients with OHCA.

A near-infrared fluorescent probe for detecting hydrogen sulfide with high selectivity in cells and ulcerative colitis in mice.

Although hydrogen sulfide (H2S) is a well-known toxic gas, its vital role as a gas transmitter in various physiological and pathological processes of living systems cannot be ignored. Relevant investigations indicate that endogenous H2S is involved in the development of ulcerative colitis pathology and is overexpressed in ulcerative colitis, and hence can be considered as an ulcerative colitis biomarker. Herein, an isophorone-xanthene-based NIR fluorescent probe (IX-H2S) was constructed to image H2S. Owing to its large conjugated structure, the probe exhibits a near-infrared emission wavelength of 770 nm with a large Stokes shift (186 nm). Moreover, IX-H2S has excellent selectivity for the detection of H2S without interference from other analytes including thiols. In addition, the probe has been successfully applied not only in fluorescence imaging of endogenous and exogenous H2S in living cells, but also in imaging of H2S in normal and ulcerative colitis mice. Encouraged by the eminent performance, IX-H2S is expected to be a potent "assistant" for the diagnosis of ulcerative colitis.

Discovery of ARD-1676 as a Highly Potent and Orally Efficacious AR PROTAC Degrader with a Broad Activity against AR Mutants for the Treatment of AR + Human Prostate Cancer.

We report herein the discovery and extensive characterization of ARD-1676, a highly potent and orally efficacious PROTAC degrader of the androgen receptor (AR). ARD-1676 was designed using a new class of AR ligands and a novel cereblon ligand. It has DC50 values of 0.1 and 1.1 nM in AR+ VCaP and LNCaP cell lines, respectively, and IC50 values of 11.5 and 2.8 nM in VCaP and LNCaP cell lines, respectively. ARD-1676 effectively induces degradation of a broad panel of clinically relevant AR mutants. ARD-1676 has an oral bioavailability of 67, 44, 31, and 99% in mice, rats, dogs, and monkeys, respectively. Oral administration of ARD-1676 effectively reduces the level of AR protein in the VCaP tumor tissue in mice and inhibits tumor growth in the VCaP mouse xenograft tumor model without any sign of toxicity. ARD-1676 is a highly promising development candidate for the treatment of AR+ human prostate cancer.

Novel Sulfonylurea-Based NLRP3 Inflammasome Inhibitor for Efficient Treatment of Nonalcoholic Steatohepatitis, Endotoxic Shock, and Colitis.

The NLRP3 inflammasome is a critical component of innate immunity involved in the pathophysiology of various inflammatory diseases. In this study, we designed and synthesized a series of NLRP3 inflammasome inhibitors based on MCC950. Specifically, we optimized the furan moiety, which is considered to be potentially associated with drug-induced liver injury. The representative inhibitor N14, 4-(2-(dimethylamino)ethyl)-N-((1,2,3,5,6,7-hexahydro-s-indacen-4-yl)carbamoyl)benzenesulfonamide, not only maintains the NLRP3 inhibitory activity of MCC950 with IC50 of 25 nM but also demonstrates improved tolerability in human hepatic cells line and mouse primary hepatocytes. In addition, N14 exhibits superior pharmacokinetic properties, with an oral bioavailability of 85.2%. In vivo studies demonstrate that N14 is more effective than MCC950 in multiple NLRP3-related animal model diseases, including nonalcoholic steatohepatitis, lethal septic shock, and colitis. Our research has provided a lead compound that directly targets the NLRP3 inflammasome and can be developed as a novel therapeutic candidate for NLRP3-driven diseases.

Discovery of BWA-522, a First-in-Class and Orally Bioavailable PROTAC Degrader of the Androgen Receptor Targeting N-Terminal Domain for the Treatment of Prostate Cancer.

We report small molecular PROTAC compounds targeting the androgen receptor N-terminal domain (AR-NTD), which were obtained by tethering AR-NTD antagonists and different classes of E3 ligase ligands through chemical linkers. A representative compound, BWA-522, effectively induces degradation of both AR-FL and AR-V7 and is more potent than the corresponding antagonist against prostate cancer (PC) cells in vitro. We have shown that the degradation of AR-FL and AR-V7 proteins by BWA-522 can suppress the expression of AR downstream proteins and induce PC cell apoptosis. BWA-522 achieves 40.5% oral bioavailability in mice and 69.3% in beagle dogs. In a LNCaP xenograft model study, BWA-522 was also proved to be an efficacious PROTAC degrader, resulting in 76% tumor growth inhibition after oral administration of a dose of 60 mg/kg. This study indicates that BWA-522 is a promising AR-NTD PROTAC for the treatment of AR-FL- and AR-V7-dependent tumors.

Discovery of ARD-2051 as a Potent and Orally Efficacious Proteolysis Targeting Chimera (PROTAC) Degrader of Androgen Receptor for the Treatment of Advanced Prostate Cancer.

We report the discovery of ARD-2051 as a potent and orally efficacious androgen receptor (AR) proteolysis-targeting chimera degrader. ARD-2051 achieves DC50 values of 0.6 nM and Dmax >90% in inducing AR protein degradation in both the LNCaP and VCaP prostate cancer cell lines, potently and effectively suppresses AR-regulated genes, and inhibits cancer cell growth. ARD-2051 achieves a good oral bioavailability and pharmacokinetic profile in mouse, rat, and dog. A single oral dose of ARD-2051 strongly reduces AR protein and suppresses AR-regulated gene expression in the VCaP xenograft tumor tissue in mice. Oral administration of ARD-2051 effectively inhibits VCaP tumor growth and causes no signs of toxicity in mice. ARD-2051 is a promising AR degrader for advanced preclinical development for the treatment of AR+ human cancers.

Precise Conformational Control Yielding Highly Potent and Exceptionally Selective BRD4 Degraders with Strong Antitumor Activity.

Starting from a nonselective bromodomain and extraterminal (BET) inhibitor and a cereblon ligand, we have used precise conformational control for the development of two potent and highly selective BRD4 degraders, BD-7148 and BD-9136. These compounds induce rapid degradation of BRD4 protein in cells at concentrations as low as 1 nM and demonstrate ≥1000-fold degradation selectivity over BRD2 or BRD3 protein. Proteomic analysis of >5700 proteins confirmed their highly selective BRD4 degradation. A single dose of BD-9136 selectively and effectively depletes BRD4 protein in tumor tissues for >48 h. BD-9136 effectively inhibits tumor growth without adverse effects on mice and is more efficacious than the corresponding pan BET inhibitor. This study suggests selective degradation of BRD4 as a strategy for the treatment of human cancers and demonstrates a strategy for the design of highly selective PROTAC degraders.

Analysis on the thermal decomposition kinetics and storage period of biomass-based lycorine galanthamine.

As global ageing deepens and galanthamine is the preferred clinical drug for the treatment of mild to moderate Alzheimer's disease, it will be valuable to examine the behaviour and mechanism of galanthamine's thermal decomposition for its quality control, formulation process, evaluation of thermal stability, and expiry date in production. In order to study the pyrolysis of galanthamine hydrobromide with nitrogen as the carrier gas, a thermogravimetric-differential thermogravimetric technique (TG-DTG) was applied at a temperature rise rate of 10 K min-1 and a volume flow rate of 35 mL min-1. The apparent activation energy E a and the prefactor A (E a = 224.45 kJ mol-1 and lnA = 47.40) of the thermal decomposition reaction of galanthamine hydrobromide were calculated according to the multiple heating rate method (Kissinger and Ozawa) and the single heating rate method (Coats-Redfern and Achar), and the most probable mechanism function was derived, and then the storage period was inferred from E a and E. A three-dimensional diffusion mechanism was suggested to control the thermal decomposition of galanthamine hydrobromide in accordance with the Jander equation, random nucleation and subsequent growth control, corresponding to the Mample one-way rule and the Avrami-Erofeev equation. As a result, the thermal decomposition temperature of galanthamine hydrobromide gradually increased with the rate of temperature rise. From Gaussian simulations and thermogravimetric data, galanthamine hydrobromide decomposed at the first stage (518.25-560.75 K) to release H2O, at the second stage (563.25-650.75 K) to generate CO, CO2, NH3 and other gases, and finally at the third stage (653.25-843.25 K) to release CO2. After 843.25 K, the residual molecular skeleton is cleaved to release CO2 and H2O. According to the E a and A presenting in the first stage of thermal decomposition, it is assumed that the storage life of galanthamine hydrobromide at room temperature 298.15 K is 4-5 years.

Efficacy and safety of salvianolate and enoxaparin in the prevention of perioperative deep venous thrombosis in gastrointestinal surgery.

OBJECTIVE: In this study, the efficacy and safety of salvianolate were compared with enoxaparin in the prevention of perioperative deep vein thrombosis in gastrointestinal surgery. METHODS: From October 2017 to September 2019, 563 patients who underwent gastrointestinal surgery were collected. Based on the inclusion and exclusion criteria, 119 patients were divided into two groups: enoxaparin group (n = 65) and salvianolate group (n = 54). Comparisons were made regarding the outcomes: prothrombin time (PT), prothrombin activity (PTA), international normalized ratio (INR), activated partial thromboplastin time (APTT), fibrinogen (FIB), thrombin time (TT), D-dimer level (D-D), platelet count (PLT), hematokrit (HCT), and incidence of deep vein thrombosis (DVT). RESULTS: The main outcomes showed no significance between enoxaparin group and salvianolate group (p > .05). The incidence of DVT in salvianolate group was 1.85%, significantly lower than that in enoxaparin group (12.3%) (p < .05). No serious adverse reactions occurred in the two groups during treatment. CONCLUSION: Compared with enoxaparin, salvianolate has an advantage in the prevention of perioperative thrombosis in gastrointestinal surgery with a lower incidence of DVT.

Design, Synthesis, and Biological Evaluation of Androgen Receptor (AR) Antagonist-Heat Shock Protein 90 (Hsp90) Inhibitor Conjugates for Targeted Therapy of Castration-Resistant Prostate Cancer.

Androgen deprivation in cases of castration-resistant prostate cancer (CRPC) leads to adverse effects, including loss of muscle and bone mass and gain of subcutaneous fat. The tumor-specific suppression of androgen receptor (AR) signaling, while not global, may reduce side effects. We present a class of small-molecular conjugates consisting of an AR antagonist linked to a heat shock protein 90 (Hsp90) inhibitor. We demonstrate that the high accumulation of Hsp90 on the surface of CRPC cells allows uptake of conjugates and increases the enrichment of drugs in the tumor cells. After penetrating prostate cancer cells, the conjugates not only inhibit AR function by the antagonist component but also bind to Hsp90 and suppress the AR protein level. Compared to AR antagonists, these conjugates showed improved tumor-targeting ability and enhanced potency against Enzalutamide-resistant 22Rv1 cells.

Inhibition of Astrocytic Carbohydrate Sulfotransferase 15 Promotes Nerve Repair After Spinal Cord Injury via Mitigation of CSPG Mediated Axonal Inhibition.

Nerve tissue regeneration is a significant problem. After neural diseases and damage such as spinal cord injury (SCI), the accumulation of chondroitin sulfate proteoglycans (CSPG) comprising axonal inhibitory glycosaminoglycan chains in the microenvironment is a major barrier that obstructs nerve repair. Interfering with the production of glycosaminoglycans, especially the critical inhibitory chains, could be a potential therapeutic strategy for SCI, which is, however, poorly defined. This study identifies Chst15, the chondroitin sulfotransferase controlling the generation of axonal inhibitory chondroitin sulfate-E, as a therapeutic target of SCI. Using a recently reported small molecular Chst15 inhibitor, this study investigates the effects of Chst15 inhibition on astrocyte behaviors and the associated consequences of in vivo disruption of the inhibitory microenvironment. Deposition of CSPGs in the extracellular matrix and migration of astrocytes are both significantly impaired by Chst15 inhibition. Administration of the inhibitor in transected spinal cord tissues of rats effectively promotes motor functional restoration and nerve tissue regeneration by a mechanism related to the attenuation of inhibitory CSPGs, glial scar formation and inflammatory responses. This study highlights the role of Chst15 in the CSPG-mediated inhibition of neural recovery after SCI and proposes an effective neuroregenerative therapeutic strategy that uses Chst15 as a potential target.

Lethal activity of BRD4 PROTAC degrader QCA570 against bladder cancer cells.

Bladder cancer is the most common malignancy of the urinary system. Efforts to identify innovative and effective therapies for bladder cancer are urgently needed. Recent studies have identified the BRD4 protein as the critical factor in regulation of cell proliferation and apoptosis in bladder cancer, and it shows promising potential for pharmacologic treatment against bladder cancer. In this study, we have evaluated the biological function of QCA570, a novel BET degrader, on multiple bladder cancer cells and explore its underlying mechanisms. QCA570 potently induces degradation of BRD4 protein at nanomolar concentrations, with a DC50 of ∼ 1 nM. It decreases EZH2 and c-MYC levels by transcriptional suppression and protein degradation. Moreover, the degrader significantly induces cell apoptosis and cycle arrest and shows antiproliferation activity against bladder cancer cells. These findings support the potential efficacy of QCA570 on bladder cancer.

PROTAC Degraders of Androgen Receptor-Integrated Dissolving Microneedles for Androgenetic Alopecia and Recrudescence Treatment via Single Topical Administration.

Androgenetic alopecia (AGA) is a transracial and cross-gender disease worldwide with a youth-oriented tendency, but it lacks effective treatment. The binding of androgen receptor (AR) and androgen plays an essential role in the occurrence and progression of AGA. Herein, novel proteolysis targeting chimera degrader of AR (AR-PROTAC) is synthesized and integrated with dissolving microneedles (PROTAC-MNs) to achieve AR destruction in hair follicles for AGA treatment. The PROTAC-MNs possess adequate mechanical capabilities for precise AR-PROTAC delivery into the hair follicle-residing regions for AR degradation. After applying only once topically, the PROTAC-MNs achieve an accelerated onset of hair regeneration as compared to the daily application of the first-line topical drug minoxidil. Intriguingly, PROTAC-MNs via single administration still realize superior hair regeneration in AGA recrudescence, which is the major drawback of minoxidil in clinical practice. With the degradation of AR, the PROTAC-MNs successfully regulate the signaling cascade related to hair growth and activate hair follicle stem cells. Furthermore, the PROTAC-MNs do not cause systemic toxicity or androgen deficiency-related chaos in vivo. Collectively, these AR-degrading dissolving microneedles with long-lasting efficacy, one-step administration, and high biocompatibility provide a great therapeutic potential for AGA treatment.

A far-red/near-infrared fluorescence probe with large Stokes shift for monitoring butyrylcholinesterase (BChE) in living cells and in vivo.

Accurate detection of butyrylcholinesterase (BChE) activity is imperative to understand its biological function and diagnose related disease. Far-red (FR)/Near-Infrared (NIR) fluorescent probe with large Stokes shift for BChE detection is extremely important. In this study, we reported a new "off-on" FR/NIR fluorescent probe (DX-2) with large Stokes shift (110 nm). DX-2 was constructed through cyclopropionate to pull-push the optical tuable hydroxyl group of chloro-substituted dicyanoisophorone fluorophore. DX-2 (λex/λem = 555/665 nm) featured high sensitivity (LOD∼0.08 U/mL) and selectivity, good pH practicability, low toxicity and good cell membrane permeability with a bright emission triggered by BChE. Furthermore, DX-2 exhibited good optical performance to image BChE activity in living cells. More importantly, the FR/NIR probe DX-2 was successfully applied to real-time monitor BChE in live tumor-bearing mouse model. These studies suggest that probe DX-2 has potential applicable value for detecting BChE in living biological systems and diagnosing BChE-related diseases.