Subsequent Death Research Articles

Oxya chinensis sinuosa (OC) Extracts Protects ARPE-19 Cells against Oxidative Stress via Activation of the Mitogen-Activated Protein Kinases (MAPKs)/ Nuclear Factor-κB (NF-κB) Pathway.

Oxya chinensis sinuosa (OC) is a well-known edible insect. Several researches on the health benefits of OC consumption have been performed to date; however, their effect on eye health remains largely unknown. This study aimed to assess the protective effects of OC extracts on the oxidative stress on the retinal pigment epithelium (RPE) cells. Oxidative damage has been identified as one of the key regulatory factors in age-related macular degeneration. H2O2-induced reactive oxygen species (ROS) production, a well-known oxidative stress factor, can cause cell death in retinal pigment epithelia cells. In this study, we found that three OC extracts effectively prevented H2O2-induced ROS production and subsequent death of ARPE-19 cells in a dose-dependent manner. In addition, the OC extracts inhibited the phosphorylation of mitogen-activated protein kinases including p38, JNK, and ERK. The OC extracts restored IκBα degradation induced by H2O2, indicating that OC extracts suppressed the activation of nuclear factor-κB. Furthermore, the three OC extracts were shown to have antioxidant effects by up-regulating the intracellular expression of key antioxidant proteins such as SOD, NQO, and HO-1. Here we demonstrated the antioxidant and anti-apoptotic effects of the OC extracts on ARPE-19, indicating their potential role in improving eye health. These results suggest that three OC extracts plays a critical role in oxidative stress-induced cell death protects in ARPE-19 cells.

Restorative justice in healthcare settings: Better outcomes for patients and medical professionals

Current responses to medical negligence insufficiently consider the broader needs of affected stakeholders. We argue that responses to medical negligence should adopt a restorative justice frame. This article recounts the experience of our daughter’s avoidable suffering and subsequent death in the healthcare system. Our experience as victims of medical negligence, and the broader literature on restorative justice, responsive regulation and health care, suggest that non-adversarial alternatives will better address the needs of victims and encourage a restoration in healthcare relationships.

Non-esterified fatty acid palmitate facilitates oxidative endoplasmic reticulum stress and apoptosis of β-cells by upregulating ERO-1α expression

Adipose tissue-derived non-esterified saturated long-chain fatty acid palmitate (PA) decisively contributes to β-cell demise in type 2 diabetes mellitus in part through the excessive generation of hydrogen peroxide (H2O2). The endoplasmic reticulum (ER) as the primary site of oxidative protein folding could represent a significant source of H2O2. Both ER-oxidoreductin-1 (ERO-1) isoenzymes, ERO-1α and ERO-1β, catalyse oxidative protein folding within the ER, generating equimolar amounts of H2O2 for every disulphide bond formed. However, whether ERO-1-derived H2O2 constitutes a potential source of cytotoxic luminal H2O2 under lipotoxic conditions is still unknown. Here, we demonstrate that both ERO-1 isoforms are expressed in pancreatic β-cells, but interestingly, PA only significantly induces ERO-1α. Its specific deletion significantly attenuates PA-mediated oxidative ER stress and subsequent β-cell death by decreasing PA-mediated ER-luminal and mitochondrial H2O2 accumulation, by counteracting the dysregulation of ER Ca2+ homeostasis, and by mitigating the reduction of mitochondrial membrane potential and lowered ATP content. Moreover, ablation of ERO-1α alleviated PA-induced hyperoxidation of the ER redox milieu. Importantly, ablation of ERO-1α did not affect the insulin secretory capacity, the unfolded protein response, or ER redox homeostasis under steady-state conditions. The involvement of ERO-1α-derived H2O2 in PA-mediated β-cell lipotoxicity was corroborated by the overexpression of a redox-active ERO-1α underscoring the proapoptotic activity of ERO-1α in pancreatic β-cells. Overall, our findings highlight the critical role of ERO-1α-derived H2O2 in lipotoxic ER stress and β-cell failure.

Modulation of NLRP3 inflammasome-related-inflammation via RIPK1/RIPK3-DRP1 or HIF-1α signaling by phenothiazine in hypothermic and normothermic neuroprotection after acute ischemic stroke

BackgroundInflammation and subsequent mitochondrial dysfunction and cell death worsen outcomes after revascularization in ischemic stroke. Receptor-interacting protein kinase 1 (RIPK1) activated dynamin-related protein 1 (DRP1) in a NLRPyrin domain containing 3 (NLRP3) inflammasome-dependent fashion and Hypoxia-Inducible Factor (HIF)-1α play key roles in the process. This study determined how phenothiazine drugs (chlorpromazine and promethazine (C + P)) with the hypothermic and normothermic modality impacts the RIPK1/RIPK3-DRP1 and HIF-1α pathways in providing neuroprotection. MethodsA total of 150 adult male Sprague-Dawley rats were subjected to 2 h middle cerebral artery occlusion (MCAO) followed by 24 h reperfusion. 8 mg/kg of C + P was administered at onset of reperfusion. Infarct volumes, mRNA and protein expressions of HIF-1α, RIPK1, RIPK3, DRP-1, NLRP3-inflammation and cytochrome c-apoptosis were assessed. Apoptotic cell death, infiltration of neutrophils and macrophages, and mitochondrial function were evaluated. Interaction between RIPK1/RIPK3 and HIF-1α/NLRP3 were determined. In SH-SY5Y cells subjected to oxygen/glucose deprivation (OGD), the normothermic effect of C + P on inflammation and apoptosis were examined. ResultsC + P significantly reduced infarct volumes, mitochondrial dysfunction (ATP and ROS concentration, citrate synthase and ATPase activity), inflammation and apoptosis with and without induced hypothermia. Overexpression of RIPK1, RIPK3, DRP-1, NLRP3-inflammasome and cytochrome c-apoptosis were all significantly reduced by C + P at 33 °C and the RIPK1 inhibitor (Nec1s), suggesting hypothermic effect of C + P via RIPK1/RIPK3-DRP1pathway. When body temperature was maintained at 37 °C, C + P and HIF-1α inhibitor (YC-1) reduced HIF-1α expression, leading to reduction in mitochondrial dysfunction, NLRP3 inflammasome and cytochrome c-apoptosis, as well as the interaction of HIF-1α and NLRP3. These were also evidenced in vitro, indicating a normothermic effect of C + P via HIF-1α. ConclusionHypothermic and normothermic neuroprotection of C + P involve different pathways. The normothermic effect was mediated by HIF-1α, while hypothermic effect was via RIPK1/RIPK3-DRP1 signaling. This provides a theoretical basis for future precise exploration of hypothermic and normothermic neuroprotection.

EURIPIDES, TROADES 95–7: IS SOMETHING MISSING?

Abstract This paper raises objections to the constitution of these lines in the OCT. The lines are gnomic but they generalize based on an actual sequence of events just described and should contain an allusion to the offence that will cause the Greeks to perish, the outrage against Athena's temple. This, it is argued, stood in a lacuna best marked after 95. The article has three theses: (1) sacking ‘cities, temples, and tombs’ is implausible because the latter two are parts of the first; (2) plundering tombs refers to nothing in the play, nor was this thought of as an offence against the gods; (3) 96–7 do not refer to the offence that causes the fool's death but are a description of his success, the destruction of the hated enemy population. That success stands in ironic contrast with his subsequent death.

Advancing tomato crop protection: Green leaf volatile-mediated defense mechanisms against Nesidiocoris tenuis plant damage

Although Nesidiocoris tenuis is highly effective as a biological control agent, it can also damage tomato plants due to its zoophytophagous behavior. When N. tenuis pierces the stems and petioles of tomato plants with its stylets, it triggers callose deposition and subsequent cell death, resulting in blocked nutrient transport, floral abortions, or wilting of tender shoots. Recently, it has been shown that exposure of tomato plants to the green leaf volatile (Z)-3-hexenyl propanoate [(Z)-3-HP] activates defensive mechanisms, including the regulation of genes involved in the synthesis and degradation of callose. In this study, conducted under greenhouse conditions, we tested the hypothesis that damage caused by N. tenuis could be reduced by exposing tomato plants to (Z)-3-HP through polymeric dispensers. Tomato plants exposed to (Z)-3-HP and non-exposed control plants were inoculated with N. tenuis. Nesidiocoris tenuis established in both groups with no significant differences between the two treatments. However, as hypothesized, the damage caused by N. tenuis was significantly lower in the plants exposed to (Z)-3-HP. Gene expression analysis of salicylic, jasmonic, and abscisic acids, along with histochemical staining methods, was used to compare the defensive responses of tomato plants infested solely with N. tenuis versus those infested with N. tenuis and exposed to (Z)-3-HP. Our findings confirm the influence of (Z)-3-HP exposure on differential defensive activation between treatments and reduced callose deposition in (Z)-3-HP-exposed plants. These results pave the way for improved management of N. tenuis by enhancing the plant's defenses based on inter-plant communication.

Durvalumab After Chemoradiotherapy in Patients With Unresectable Stage III Non–Small Cell Lung Cancer

The PACIFIC trial established consolidation durvalumab as the standard of care following chemoradiotherapy (CRT) for patients with unresectable stage III non-small cell lung cancer (NSCLC). Understanding its benefit in routine US clinical practice is critical. To report characteristics, treatment patterns, and outcomes of patients who did or did not receive durvalumab. Two prespecified cohorts were curated in this retrospective cohort study (SPOTLIGHT). Deidentified patient-level data from a US database (Flatiron Health) were analyzed. Patients had unresectable stage III NSCLC, were diagnosed on or after January 1, 2011, had 2 or more visits on or afterward, and received CRT. Data were analyzed from May 2021 to October 2023. Patients started durvalumab after CRT (durvalumab cohort) or ended CRT without durvalumab (nondurvalumab cohort) by June 30, 2019, to allow 15 or more months of follow-up from CRT end. End points included progression-free survival (PFS), overall survival (OS), time to first subsequent therapy or death (TFST), and time to distant metastasis or death (TTDM). The durvalumab cohort included 332 patients (median [IQR] age, 67.5 [60.8-74.0] years; 187 were male [56.3%], 27 were Black [8.7%], 33 were other races [10.7%], and 249 were White [80.6%]) and the nondurvalumab cohort included 137 patients (median (IQR) age, 70.0 [64.0-75.0] years; 89 [65.0%] were male, 11 [8.9%] were Black, 19 [15.4%] were other races, and 93 [75.6%] were White). Most patients had a smoking history (durvalumab, 316 patients [95.2%] and nondurvalumab, 132 patients [96.4%]) and Eastern Cooperative Oncology Group performance status 0 through 1 (durvalumab, 251 patients [90.9%] and nondurvalumab, 88 patients [81.5%]). Median (IQR) CRT duration was 1.6 (1.4-1.8) months for the durvalumab cohort and 1.5 (1.4-1.8) months for the nondurvalumab cohort. Median time to durvalumab discontinuation was 9.5 months (95% CI, 7.8-10.6 months). Median TFST and TTDM were not reached (NR) in the durvalumab cohort and 8.3 months (95% CI, 4.8-11.8 months) and 11.3 months (95% CI, 6.4-14.5 months), respectively, in the nondurvalumab cohort. Median PFS and OS were 17.5 months (95% CI, 13.6-24.8 months) and NR in the durvalumab cohort and 7.6 months (95% CI, 5.2-9.8 months) and 19.4 months (95% CI, 11.7-24.0 months) in the nondurvalumab cohort. In Cox regression analyses of patients who completed concurrent CRT without progression, durvalumab was associated with a lower risk of progression or death (hazard ratio [HR], 0.36; 95% CI, 0.26-0.51) and lower risk of death (HR, 0.27; 95% CI, 0.16-0.43), adjusted for prior platinum agent and patient characteristics. In this cohort study, findings were consistent with PACIFIC, and durvalumab was associated with a lower risk of progression and/or death. Further investigation is warranted to explain why patients did not receive durvalumab after its approval.

A prospective cohort study of exposure to household pesticide with cardiovascular diseases mortality in older adults

ObjectivesWe examined the associations of self-reported exposures, and urinary metabolites related to household pesticide with cardiovascular disease (CVD) mortality in older adults based on the 2007 to 2014 waves of National Health and Nutrition Examination Survey (NHANES). MethodsInformation on application and urinary metabolites related to household pesticide exposure were collected. We estimated the risks of household pesticide exposure, urinary metabolites with subsequent incident CVD death using Cox proportional hazards regression models. The indirect effects of urinary metabolites and effect modifications were examined. ResultsThe participants who reported exposure to household pesticide had a higher risk of incident CVD death (adjusted HR 1.40, 95% CI 1.08 to 1.81). Per 1-log10 increase in urinary N, N-diethyl-3-methylbenzamide (DEET) related to household insect repellents was associated with a higher risk of incident CVD death (adjusted HR 1.97, 95% CI 1.14 to 3.40). Urinary DEET explained 4.21% of the total association between household pesticide exposure and CVD death risk. The participants who persisted a low level of health diet exhibited pronounced CVD death risks with household pesticide exposures. ConclusionsExposure to household pesticide, especially household insect repellents, was consistently associated with an elevated CVD death risk in older adults. A heatlhy diet could partly attenuate the associations.

Prognostic performance of soluble urokinase plasminogen activator receptor for heart failure or mortality in Western and Asian patients with acute breathlessness

AimsThe performance of circulating soluble urokinase plasminogen activator receptor (suPAR) for predicting the composite endpoint of subsequent heart failure (HF) hospitalisation and/or death at 1 year was assessed in (i) patients with undifferentiated breathlessness, and generalisability was compared in (ii) disparate Western versus Asian sub-cohorts, and in (iii) the sub-cohort adjudicated with HF. Methods and resultsPatients with acute breathlessness were recruited from the emergency departments in New Zealand (NZ, n = 612) and Singapore (n = 483). suPAR measured in the presentation samples was higher in patients incurring the endpoint (n = 281) compared with survivors (5.2 ng/mL vs 3.1 ng/mL, P < 0.0001). The discriminative power of suPAR for endpoint prediction was c-statistic of 0.77 in the combined population, but was superior in Singapore than NZ (c-statistic: 0.83 vs 0.71, P < 0.0001). Although the highest suPAR tertile (>4.37 ng/mL) was associated with risks of >4-fold in NZ, >20-fold in Singapore, and ≥3-fold in HF for incurring the outcome, there was no interaction between country and suPAR levels after adjustment. Multivariable analysis indicated suPAR to be robust in predicting HF/death at 1-year [hazard ratio: 1.9 (95% CI:1.7 to 2.0) per SD increase] and improved risk discrimination for outcome prediction in HF (∆0.06) and for those with NT-proBNP >1000 pg/mL (∆0.02). ConclusionsuPAR is a strong independent predictor of HF and/or death at 1 year in acutely breathless patients, in both Asian and Western cohorts, and in HF. suPAR may improve stratification of acutely breathless patients, and in acute HF, for risk of later onset of heart failure or mortality.

Arrhythmia Burden Among Adult PatientsWith Congenital Heart Disease: APopulation-Based Study.

A significant percentage of patients with congenital heart disease surviving into adulthood will develop arrhythmias. These arrhythmias are associated with an increased risk of adverse events and death. We aimed to assess arrhythmia prevalence, risk factors, and associated health care usage in a large national cohort of patients with adult congenital heart disease. Adults with a documented diagnosis of congenital heart disease, insured by Clalit and Maccabi health services between January 2007 and December 2011, were included. We assessed the associations between arrhythmia and subsequent hospitalization rates and death with mixed negative binomial and Cox proportional hazard models, respectively. Among 11 653 patients with adult congenital heart disease (median age, 47 years [interquartile range, 31-62]), 8.7% had a tachyarrhythmia at baseline, 1.5% had a conduction disturbance, and 0.5% had both. Among those without a baseline arrhythmia, 9.2% developed tachyarrhythmias, 0.9% developed a conduction disturbance, and 0.3% developed both during the study period. Compared with no arrhythmia (reference group), arrhythmia in the previous 6 months was associated with a higher multivariable adjusted hospitalization rate, 1.33-fold higher than the rate of the reference group (95% CI, 1.00-1.76) for ventricular arrhythmia, 1.27-fold higher (95% CI, 1.17-1.38) for atrial arrhythmias, and 1.33-fold higher (95% CI, 1.04-1.71) for atrioventricular block. Atrial tachyarrhythmias were associated with an adjusted mortality hazard ratio (HR) of 1.65 (95% CI, 1.44-2.94), and ventricular tachyarrhythmias with a >2-fold increase in mortality risk (HR, 2.06 [95% CI, 1.44-2.94]). Arrhythmias are significant comorbidities in the adult congenital heart disease population and have a significant impact on health care usage and survival.

Clinical Outcomes of Patients with Atrial Fibrillation who Survived from Bleeding Event: The Results from COOL-AF Thailand Registry.

Bleeding events are often reported among patients with atrial fibrillation (AF), irrespective of antithrombotic use. This study is to determine clinical outcomes of patients with AF who survived from bleeding event. We analyzed data from COOL-AF (Cohort of Antithrombotic Use and Optimal International Normalized Ratio Levels in Patients with Atrial Fibrillation) Thailand registry. Outcomes of patients who experienced any bleeding were compared with patients who had never bleed. Time updated multivariate Cox-proportional hazard models were used to estimate the risk for clinical outcomes of patients with and without bleeding. Of total 3,405 patients (mean age: 67.8 ± 11.3 years; 41.9% female) in COOL-AF registry, 609 patients (17.9%) reported bleeding event occurs and 568 patients (93.3%) survived though hospital discharge. Patients who survived major bleeding (n = 126) were at increased risk for both death (adjusted hazard ratio [HR]: 4.44, 95% confidence interval [CI]: 2.91-6.75, p < 0.001) and stroke/systemic embolism (adjusted HR: 4.49, 95% CI: 2.19-9.24, p < 0.001). Minor bleeding also increased subsequent death (adjusted HR: 2.13, 95% CI: 1.56-2.90, p < 0.001). Up to 30% of patients who survived major bleeding and 6.3% of minor bleedings discontinued oral anticoagulation. Discontinuation was associated with very high death rate (42.1%), whereas patients who resumed oral anticoagulation after bleeding had lower mortality (10%). The most common causes of death in patients who survived a bleeding event were not related to cardiovascular causes nor bleeding. Patients with AF who have bleeding events have an increased risk for subsequent death and stroke and systemic embolism. These patients should be identified as vulnerable clinically complex patients and require a holistic approach to their AF management.

Association of device detected atrial and ventricular tachyarrhythmia with adverse events in patients with an implantable cardioverter-defibrillator.

Heart failure patients with a history of atrial fibrillation (AF) and ventricular tachycardia/ventricular fibrillation (VT/VF) are known to have worse outcomes. However, there are limited data on the temporal relationship between development of these arrhythmias and the risk of subsequent congestive heart failure (CHF) exacerbation and death. The study cohort comprised 5511 patients implanted with an implantable cardioverter-defibrillator (ICD) in landmark clinical trials (MADIT-II, MADIT-RISK, MADIT-CRT, MADIT-RIT, and RAID) who were in sinus rhythm at enrollment. Multivariate cox analysis was performed to evaluate the time-dependent association between development of in-trial device detected AF and VT/VF with subsequent CHF exacerbation and death. Multivariate analysis showed that AF occurrence and VT/VF occurrence were both associated with a similar magnitude of risk for subsequent CHF exacerbation (HR = 1.73 and 1.87 respectively, p < .001 for both). In contrast, only in-trial VT/VF was associated with a significant > two-fold increase in the risk of subsequent mortality (HR = 2.13, p < .001) whereas AF occurrence was not associated with a significant mortality increase after adjustment for in-trial VT/VF (HR = 1.36, p = .096). Our findings from a large cohort of ICD recipients enrolled in landmark clinical trials show that device detected AF and VT/VF can be used to identify patients with increased risk for CHF exacerbation and mortality. These findings suggest a need for early intervention in CHF patients who develop device-detected atrial and ventricular tachyarrhythmias.

Quantum chemistry calculation-aided discovery of potent small-molecule mimics of glutathione peroxidases for the treatment of cisplatin-induced hearing loss

Hearing loss (HL) is a health burden that seriously affects the quality of life of cancer patients receiving platinum-based chemotherapy, and few FDA-approved treatment specifically targets this condition. The main mechanisms that contribute to cisplatin-induced hearing loss are oxidative stress and subsequent cell death, including ferroptosis revealed by us as a new mechanism recently. In this study, we employed the frontier molecular orbital (FMO) theory approach as a convenient prediction method for the glutathione peroxidase (GPx)-like activity of isoselenazolones and discovered new isoselenazolones with great GPx-like activity. Notably, compound 19 exhibited significant protective effects against cisplatin-induced hair cell (HC) damage in vitro and in vivo and effectively reverses cisplatin-induced hearing loss through oral administration. Further investigations revealed that this compound effectively alleviated hair cell oxidative stress, apoptosis and ferroptosis. This research highlights the potential of GPx mimics as a therapeutic strategy against cisplatin-induced hearing loss. The application of quantum chemistry (QC) calculations in the study of GPx mimics sheds light on the development of new, innovative treatments for hearing loss.

Application of the Universal Definition of Myocardial Infarction in Clinical Practice in Scotland and Sweden

Whether the diagnostic classifications proposed by the universal definition of myocardial infarction (MI) to identify type 1 MI due to atherothrombosis and type 2 MI due to myocardial oxygen supply-demand imbalance have been applied consistently in clinical practice is unknown. To evaluate the application of the universal definition of MI in consecutive patients with possible MI across 2 health care systems. This cohort study used data from 2 prospective cohorts enrolling consecutive patients with possible MI in Scotland (2013-2016) and Sweden (2011-2014) to assess accuracy of clinical diagnosis of MI recorded in hospital records for patients with an adjudicated diagnosis of type 1 or type 2 MI. Data were analyzed from August 2022 to February 2023. The main outcome was the proportion of patients with a clinical diagnosis of MI recorded in the hospital records who had type 1 or type 2 MI, adjudicated by an independent panel according to the universal definition. Characteristics and risk of subsequent MI or cardiovascular death at 1 year were compared. A total of 50 356 patients were assessed. The cohort from Scotland included 28 783 (15 562 men [54%]; mean [SD] age, 60 [17] years), and the cohort from Sweden included 21 573 (11 110 men [51%]; mean [SD] age, 56 [17] years) patients. In Scotland, a clinical diagnosis of MI was recorded in 2506 of 3187 patients with an adjudicated diagnosis of type 1 MI (79%) and 122 of 716 patients with an adjudicated diagnosis of type 2 MI (17%). Similar findings were observed in Sweden, with 970 of 1111 patients with adjudicated diagnosis of type 1 MI (87%) and 57 of 251 patients with adjudicated diagnosis of type 2 MI (23%) receiving a clinical diagnosis of MI. Patients with an adjudicated diagnosis of type 1 MI without a clinical diagnosis were more likely to be women (eg, 336 women [49%] vs 909 women [36%] in Scotland; P < .001) and older (mean [SD] age, 71 [14] v 67 [14] years in Scotland, P < .001) and, when adjusting for competing risk from noncardiovascular death, were at similar or increased risk of subsequent MI or cardiovascular death compared with patients with a clinical diagnosis of MI (eg, 29% vs 18% in Scotland; P < .001). In this cohort study, the universal definition of MI was not consistently applied in clinical practice, with a minority of patients with type 2 MI identified, and type 1 MI underrecognized in women and older persons, suggesting uncertainty remains regarding the diagnostic criteria or value of the classification.

The impact of ribosome biogenesis in cancer: from proliferation to metastasis.

The dysregulation of ribosome biogenesis is a hallmark of cancer, facilitating the adaptation to altered translational demands essential for various aspects of tumor progression. This review explores the intricate interplay between ribosome biogenesis and cancer development, highlighting dynamic regulation orchestrated by key oncogenic signaling pathways. Recent studies reveal the multifaceted roles of ribosomes, extending beyond protein factories to include regulatory functions in mRNA translation. Dysregulated ribosome biogenesis not only hampers precise control of global protein production and proliferation but also influences processes such as the maintenance of stem cell-like properties and epithelial-mesenchymal transition, contributing to cancer progression. Interference with ribosome biogenesis, notably through RNA Pol I inhibition, elicits a stress response marked by nucleolar integrity loss, and subsequent G1-cell cycle arrest or cell death. These findings suggest that cancer cells may rely on heightened RNA Pol I transcription, rendering ribosomal RNA synthesis a potential therapeutic vulnerability. The review further explores targeting ribosome biogenesis vulnerabilities as a promising strategy to disrupt global ribosome production, presenting therapeutic opportunities for cancer treatment.

Cannabidiol improves the cognitive function of SAMP8 AD model mice involving the microbiota-gut-brain axis

ABSTRACT Cannabidiol (CBD), a natural component extracted from Cannabis sativa L. exerts neuroprotective, antioxidant, and anti-inflammatory effects in Alzheimer’s disease (AD), a disease characterized by impaired cognition and accumulation of amyloid-B peptides (Aβ). Interactions between the gut and central nervous system (microbiota-gut-brain axis) play a critical role in the pathogenesis of neurodegenerative disorder AD. At present investigations into the mechanisms underlying the neuroprotective action of CBD in AD are not conclusive. The aim of this study was thus to examine the influence of CBD on cognition and involvement of the microbiota-gut-brain axis using a senescence-accelerated mouse prone 8 (SAMP8) model. Data demonstrated that administration of CBD to SAMP8 mice improved cognitive function as evidenced from the Morris water maze test and increased hippocampal activated microglia shift from M1 to M2. In addition, CBD elevated levels of Bacteriodetes associated with a fall in Firmicutes providing morphologically a protective intestinal barrier which subsequently reduced leakage of intestinal toxic metabolites. Further, CBD was found to reduce the levels of hippocampal and colon epithelial cells lipopolysaccharide (LPS), known to be increased in AD leading to impaired gastrointestinal motility, thereby promoting neuroinflammation and subsequent neuronal death. Our findings demonstrated that CBD may be considered a beneficial therapeutic drug to counteract AD-mediated cognitive impairment and restore gut microbial functions associated with the observed neuroprotective mechanisms.

Abstract LB272: Sequential inhibition of PARP and BET as a rational therapeutic strategy for glioblastoma multiforme

Abstract Glioblastoma multiforme (GBM), characterized as one of the most aggressive brain cancers, presents significant treatment challenges due to its rapid growth, heterogeneity, and robust defensive mechanisms. Despite advancements in neuro-oncology, GBM's prognosis remains grim, with the median survival of approximately 15 months, underscoring the urgent need for innovative therapeutic strategies. Facing these challenges, PARP inhibitors (PARPi) hold substantial promise in treating GBM, evidenced by over 20 ongoing clinical trials. However, their application has been limited by side effects such as nausea, fatigue, and particularly anemia, as well as a narrow therapeutic spectrum focusing mainly on patients with homologous recombination deficiency (HRDness). Through unbiased transcriptomic and proteomic sequencing, and employing Gene Ontology (GO) and Gene Set Enrichment Analysis (GSEA), and Transcriptome-Proteome Correlation Analysis, we discovered that the BET inhibitor (BETi) Birabresib profoundly alters the processes of DNA replication and cell cycle progression in GBM cells, extending beyond the previously known impact of BET inhibition on homologous recombination repair. In vitro experiments using GBM cell lines and patient-derived primary GBM cells demonstrated that concurrent administration of PARPi and BETi can synergistically inhibit GBM. Intriguingly, we observed that DNA damage persists after the discontinuation of PARPi monotherapy. Leveraging these residual effects of PARPi, subsequent BETi administration elevated replication stress levels, leading to the inactivation of GBM cell cycle checkpoints, with efficacy comparable to concurrent treatment. The treatment-induced prolonged stalling of replication forks resulted in their collapse and the formation of double-ended double-strand breaks (DSBs). In GBM cells with elevated baseline replication stress, the sequential regimen exhibits comparable efficacy to concurrent treatment, while protecting normal glial cells with lower baseline replication stress from DNA toxicity and subsequent death. In vivo orthotopic transplantation tumor experiments in zebrafish and nude mice demonstrated consistent effects, indicating that sequential administration of PARPi followed by BETi maintained anti-tumor efficacy, similar to concurrent treatment, while reducing toxicity, as evident by the reduced impact on hemoglobin levels. Our findings provide a broader and deeper understanding of the synergistic interaction between BETi and PARPi than previously recognized. This study offers compelling preclinical evidence supporting the development of innovative drug administration strategies focusing on PARPi for GBM therapy. Citation Format: Xin Peng, Xin Huang, Shaolu Zhang, Naixin Zhang, Shengfan Huang, Yingying Wang, Zhenxing Zhong, Shan Zhu, Haiwang Gao, Zixiang Yu, Xiaotong Yan, Zhennan Tao, Yuxiang Dai, Zhe Zhang, Xi Chen, Feng Wang, Francois X. Claret, Ning Ji, Yuxu Zhong, Dexin Kong. Sequential inhibition of PARP and BET as a rational therapeutic strategy for glioblastoma multiforme [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB272.

Abstract LB413: A newly developed patient-derived culture panel identifies precision therapies and pan-effective agents for head and neck squamous cell carcinoma

Abstract Head and neck squamous carcinoma (HNSCC) is an aggressive cancer with few treatment options. Its well-known genetic heterogeneity presents a major challenge for precision medicine development. We report a newly developed panel of 20 HNSCC patient-derived cultures (HNSCC-PDCs) from advanced or recurrent HNSCC, with comprehensive somatic and germline characterization for precision medicine (PM) discovery. The PDCs retain genetic heterogeneity of the original patient tumors, and xenografts of which also phenocopied HNSCC patient tumors. Importantly, somatic and germline events that were never or seldom captured by long-established HNSCC cell lines are represented by the PDC panel, including HRAS-CASP8 co-mutations, EGFR-AS1 germline mutation, exonic germline PIK3CA mutation, sonic hedgehog (SHH) pathway and FGFR pathway mutations. We hypothesize that drug screening with this newly developed HNSCC-PDC panel that recapitulates HNSCC patient genetics may identify new gene-drug sensitivity relationships for precision medicine development in advanced HNSCC. Here, data from our pilot drug screen of 38 selected FDA approved/Phase I-II clinical trial agents first reveal: 1) HNSCC-PDC with the hotspot HRASp.G13R, together with CASP8p.L183S, is sensitive to tipifarnib vs. tipifarnib-resistance in a long-established HNSCC cell line, SNU899 with the same HRAS mutation. Subsequent high-content imaging cell death assay further demonstrates a dose-dependent tipifarnib-induced cell death in HRASp.G13R-mutated PDC, but not in SNU-899; 2) TP53-EP300 co-mutated HNSCC-PDCs are most sensitive to cisplatin with ~340 nM sensitivity (mean IC50) among all PDCs tested, which is 22 times more sensitive than that reported in Genomics of Drug Sensitivity in Cancer (GDSC) HNSCC cell lines; 3) EGFR-AS1 (c.2361G&amp;gt;A)-germline mutated PDCs, and MAPK1-mutated PDCs, are both hypersensitive to EGFR inhibitors (EGFRi: erlotinib and mobocertinib), which independently credentialed gene-drug sensitivity relationships reported in exceptional responders in HNSCC clinical trials. Further signaling investigation in PDC models demonstrates phospho-MAPK activation as a reliable surrogate biomarker for EGFRi sensitivity in HNSCC; 4) FRS3-mutated PDCs are sensitive to FDA-approved FGFR pathway inhibitors; and 5) TP53-wildtype HNSCC-PDCs are 150-fold more sensitive to novel p53-MDM2 interaction inhibitors vs. TP53-mutated PDCs, a phenomenon that cannot be captured in long-established TP53-wildtype HNSCC cell lines. Lastly, 4 pan-PDC effective agents are identified with nM sensitivities and high drug activities (i.e. drug-induced growth inhibition) in more than half of our PDC models. These include 3 FDA-approved agents, TAK-981, Selinexor (a novel XPO1 inhibitor), and trametinib, as well as the preclinical agent JQ1. In conclusion, our pilot HNSCC-PDC drug screen identifies new gene-drug sensitivity relationships for HNSCC PM development and new pan-effective agents for advanced HNSCC. Citation Format: Yuen Keng Ng, Hui Li, Wenying Piao, Cecilia Pik Yuk Lau, Peony Hiu Yan Poon, Tin Yu Samuel Law, Jason Ying Kuen Chan, Yuxiong Su, Chin Wang Lau, Zigui Chen, Laura Ren Huey Ip, Thomas Chung-Kit Yeung, Sai Fung Yeung, Jason Hoi-Lam Ngan, Zoey Wing Yee Liu, Noah R. Wiese, Vivie Vo, Zoey Patel, Jeremia Onyekachi, Laili Afzali, Jasmine Zohal Afzali, Jack Nimitz Smith, Vivian Wai Yan Lui. A newly developed patient-derived culture panel identifies precision therapies and pan-effective agents for head and neck squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB413.

GSH-responsive degradable nanodrug for glucose metabolism intervention and induction of ferroptosis to enhance magnetothermal anti-tumor therapy

The challenges associated with activating ferroptosis for cancer therapy primarily arise from obstacles related to redox and iron homeostasis, which hinder the susceptibility of tumor cells to ferroptosis. However, the specific mechanisms of ferroptosis resistance, especially those intertwined with abnormal metabolic processes within tumor cells, have been consistently underestimated. In response, we present an innovative glutathione-responsive magnetocaloric therapy nanodrug termed LFMP. LFMP consists of lonidamine (LND) loaded into PEG-modified magnetic nanoparticles with a Fe3O4 core and coated with disulfide bonds-bridged mesoporous silica shells. This nanodrug is designed to induce an accelerated ferroptosis-activating state in tumor cells by disrupting homeostasis. Under the dual effects of alternating magnetic fields and high concentrations of glutathione in the tumor microenvironment, LFMP undergoes disintegration, releasing drugs. LND intervenes in cell metabolism by inhibiting glycolysis, ultimately enhancing iron death and leading to synthetic glutathione consumption. The disulfide bonds play a pivotal role in disrupting intracellular redox homeostasis by depleting glutathione and inactivating glutathione peroxidase 4 (GPX4), synergizing with LND to enhance the sensitivity of tumor cells to ferroptosis. This process intensifies oxidative stress, further impairing redox homeostasis. Furthermore, LFMP exacerbates mitochondrial dysfunction, triggering ROS formation and lactate buildup in cancer cells, resulting in increased acidity and subsequent tumor cell death. Importantly, LFMP significantly suppresses tumor cell proliferation with minimal side effects both in vitro and in vivo, exhibiting satisfactory T2-weighted MR imaging properties. In conclusion, this magnetic hyperthermia-based nanomedicine strategy presents a promising and innovative approach for antitumor therapy.Graphical

Prophage maintenance is determined by environment-dependent selective sweeps rather than mutational availability

Prophages, viral sequences integrated into bacterial genomes, can be beneficial and costly. Despite the risk of prophage activation and subsequent bacterial death, active prophages are present in most bacterial genomes. However, our understanding of the selective forces that maintain prophages in bacterial populations is limited. Combining experimental evolution with stochastic modeling, we show that prophage maintenance and loss are primarily determined by environmental conditions that alter the net fitness effect of a prophage on its bacterial host. When prophages are too costly, they are rapidly lost through environment-specific sequences of selective sweeps. Conflicting selection pressures that select against the prophage but for a prophage-encoded accessory gene can maintain prophages. The dynamics of prophage maintenance additionally depend on the sociality of this accessory gene. Prophage-encoded genes that exclusively benefit the lysogen maintain prophages at higher frequencies compared with genes that benefit the entire population. That is because the latter can protect phage-free "cheaters," reducing the benefit of maintaining the prophage. Our simulations suggest that environmental variation plays a larger role than mutation rates in determining prophage maintenance. These findings highlight the complexity of selection pressures that act on mobile genetic elements and challenge our understanding of the role of environmental factors relative to random chance events in shaping the evolutionary trajectory of bacterial populations. By shedding light on the key factors that shape microbial populations in the face of environmental changes, our study significantly advances our understanding of the complex dynamics of microbial evolution and diversification.