Preclinical Findings Research Articles

Respiratory neuropathology in spinocerebellar ataxia type 7.

Spinocerebellar ataxia type 7 (SCA7) is an autosomal dominant neurological disorder caused by deleterious CAG repeat expansion in the coding region of the ataxin 7 gene (polyQ-ataxin-7). Infantile-onset SCA7 leads to severe clinical manifestation of respiratory distress, but the exact cause of respiratory impairment remains unclear. Using the infantile-SCA7 mouse model, the SCA7266Q/5Q mouse, we examined the impact of pathological polyQ-ataxin-7 on hypoglossal (XII) and phrenic motor units. We identified the transcript profile of the medulla and cervical spinal cord and investigated the XII and phrenic nerves and the neuromuscular junctions in the diaphragm and tongue. SCA7266Q/5Q astrocytes showed significant intranuclear inclusions of ataxin-7 in the XII and putative phrenic motor nuclei. Transcriptomic analysis revealed dysregulation of genes involved in amino acid and neurotransmitter transport and myelination. Additionally, SCA7266Q/5Q mice demonstrated blunted efferent output of the XII nerve and demyelination in both XII and phrenic nerves. Finally, there was an increased number of neuromuscular junction clusters with higher expression of synaptic markers in SCA7266Q/5Q mice compared with WT controls. These preclinical findings elucidate the underlying pathophysiology responsible for impaired glial cell function and death leading to dysphagia, aspiration, and respiratory failure in infantile SCA7.

Subchronic intranasal lipopolysaccharide exposure induces pulmonary autoimmunity and glomerulonephritis in NZBWF1 mice

Lupus, a systemic autoimmune disease shaped by gene-environment interplay, often progresses to endstage renal failure. While subchronic systemic exposure to bacterial lipopolysaccharide (LPS) triggers autoimmunity and glomerulonephritis in lupus-prone mice, it is unknown if inhaling LPS, which is common in certain occupations, can similarly trigger lupus. Here we determined how subchronic intranasal (IN) LPS instillation influences autoimmunity and glomerulonephritis development in lupusprone NZBWF1 female mice. Briefly, mice were IN-instilled with vehicle or E. coli LPS (0.8 μg/g) twice weekly for 5 wk, followed by necropsy. For systemic comparison, additional cohorts of mice were injected with LPS intraperitoneally (IP) using identical doses/timing. Lungs were assessed for inflammatory and autoimmune responses and then related to systemic autoimmunity and glomerulonephritis. IN/LPS exposure induced in the lung: i) leukocyte infiltration, ii)mRNA signatures for cytokines, chemokines, IFN-regulated, and cell death-related genes, iii) ectopic lymphoid tissue formation, and iv)diverse IgM and IgG autoantibodies (AAbs). Pulmonary effects coincided with enlarged spleens, elevated plasma IgG AAbs, and inflamed IgG-containing kidney glomeruli. In contrast, IP/LPS treatment induced systemic autoimmunity and glomerulonephritis without pulmonary manifestations. Taken together, these preclinical findings suggest the lung could serve as a critical nexus for triggering autoimmunity by respirable LPS in genetically predisposed individuals.

Pink1 gene: a key player in the pathophysiology of type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is a complicated metabolic condition with insulin resistance and poor glucose metabolism. Emerging evidence indicates the significance of (PTEN-induced putative kinase 1 (Pink1) in the progression of diseases. Pink1 encodes a protein kinase, which regulates and maintains mitochondrial activity, this mostly affects mitophagy and energy generation. Mutations in the Pink1 gene have been associated to oxidative stress, mitochondrial malfunction, and impaired cellular energy output. The presence of insulin resistance and T2DM may be caused by each of these characteristics. To understand Pink1 potential function in the development of diabetes, this review paper investigates the molecular mechanisms through which it influences glucose metabolism and insulin signaling. Based on preclinical investigations, there is potential for developing innovative therapeutic strategies that specifically target Pink1. These strategies could aim to regulate insulin resistance, improve glucose metabolism, and preserve beta-cell function among individuals diagnosed with diabetes. The following areas of research include figuring out how precisely Pink1 functions in diabetes, translating preclinical findings into clinical settings, exploring precision medicine approaches that specifically target Pink1, and identifying possible therapeutic targets within the Pink1 pathway. This review aims to enhance our understanding of Pink1 impact on T2DM and develop personalized treatments for metabolic disorders. Furthermore, it underscores the significance of persisting with this type of investigation to enhance diabetes treatment strategies.

Boosting the anti-tumor activity of natural killer cells by caripe 8 – A Carapichea ipecacuanha isolated cyclotide

Cyclotides are head-to-tail cyclized peptides with a unique cystine-knot motif. Their structure provides exceptional resistance against enzymatic, chemical, or thermal degradation compared to other peptides. Peptide-based therapeutics promise high specificity, selectivity and lower immunogenicity, making them safer alternatives to small molecules or large biologicals. Cyclotides were researched due to their anti-cancer properties by inducing apoptosis in tumor cells in the past, but the impact of cyclotides on cytotoxic immune cells was poorly studied. Natural Killer (NK) cells are cytotoxic innate lymphoid cells and play an important role in the defense against infected, stressed and transformed cells. NK cells do not need prior sensitization and act in an antigen independent manner, holding promising potential in the field of immunotherapy. To investigate the effect of immunomodulatory cyclotides on NK cells, we evaluated several peptide-enriched plant extracts on NK cell mediated cytotoxicity. We observed that the extract samples derived from Carapichea ipecacuanha (Brot.) L. Andersson augments the killing potential of mouse NK cells against different tumor targets in vitro. Subsequent isolation of cyclotides from C. ipecacuanha extracts led to the identification of a primary candidate that enhances cytotoxicity of both mouse and human NK cells. The augmented killing is facilitated by the increased degranulation capacity of NK cells. In addition, we noted a direct toxic effect of caripe 8 on tumor cells, suggesting a dual therapeutic potential in cancer treatment. This study offers novel insights how natural peptides can influence NK cell cytotoxicity. These pre-clinical findings hold significant promise for advancing current immunotherapeutic approaches.

Preclinical evaluation of [18F]FP-CIT, the radiotracer targeting dopamine transporter for diagnosing Parkinson’s disease: pharmacokinetic and efficacy analysis

BackgroundN-(3-fluoropropyl)-2β-carboxymethoxy-3β-(4-iodophenyl) nortropane (FP-CIT), the representative cocaine derivative used in dopamine transporter imaging, is a promising biomarker, as it reflects the severity of Parkinson’s disease (PD). 123I- and 18F-labeled FP-CIT has been used for PD diagnosis. However, preclinical studies evaluating [18F]FP-CIT as a potential diagnostic biomarker are scarce. Among translational research advancements from bench to bedside, translating preclinical findings into clinical practice is one-directional. The aim of this study is to employ a circular approach, beginning back from the preclinical stage, progressing to the supplementation of [18F]FP-CIT, and subsequently returning to clinical application. We investigated the pharmacokinetic properties of [18F]FP-CIT and its efficacy for PD diagnosis using murine models.ResultsBiodistribution, metabolite and excretion analyses were performed in mice and PD models were induced in rats using 6-hydroxydopamine (6-OHDA). The targeting efficiency of [18F]FP-CIT for the dopamine receptor was assessed through animal PET/CT imaging. Subsequently, correlation analysis was conducted between animal PET/CT imaging results and immunohistochemistry (IHC) targeting tyrosine hydroxylase. Rapid circulation was confirmed after [18F]FP-CIT injection. [18F]FP-CIT reached the highest uptake of 23.50 ± 12.46%ID/g in the striatum 1 min after injection, and it was rapidly excreted within 60 min. The major metabolic organs of [18F]FP-CIT were confirmed to be the intestines, liver, and kidneys. Its uptake in the intestine was approximately 5% ID/g. The uptake in the liver gradually increased, with excretion beginning after reaching a maximum after 60 min. The kidneys exhibited rapid elimination after 10 min. In the excretion study, rapid elimination was verified, with 21.46 ± 9.53% of the compound excreted within a 6 h period. Additionally, the efficacy of [18F]FP-CIT PET was demonstrated in the PD model, with a high correlation with IHC for both the absolute value (R = 0.803, p = 0.0017) and the ratio value (R = 0.973, p = 0.0011).ConclusionsThis study fills the gap regarding insufficient preclinical studies on [18F]FP-CIT, including its ADME, metabolites, and efficiency. The pharmacological results, including accurate diagnosis, rapid circulation, and [18F]FP-CIT excretion, provide complementary evidence that [18F]FP-CIT can be used safely and efficiently to diagnose PD in clinics, although it is already used in clinics.

Antimicrobial Potential of Polyphenols: An Update on Alternative for Combating Antimicrobial Resistance.

The last decade has encountered an increasing demand for plant-based natural antibiotics. This demand has led to more research-based investigations for natural sources of antimicrobial agents and published reports demonstrating that plant extracts are widely applied in modern medicine, reporting potential activity that may be due to polyphenol compounds. Interestingly, the effects of polyphenols on the sensitivity of bacteria to antibiotics have not been well-studied. Hence, the current review encompasses the prospective application of plant-based phenolic extracts from plants of Indian origin. The emergence of resistance to antimicrobial agents has increased the inefficacy of many antimicrobial drugs. Several strategies have been developed in recent times to overcome this issue. A combination of antimicrobial agents is employed for the failing antibiotics, which restores the desirable effect but may have toxicity-related issues. Phytochemicals such as some polyphenols have demonstrated their potent activity as antimicrobial agents of natural origin to work against resistance issues. These agents alone or in combination with certain antibiotics have been shown to enhance the antimicrobial activity against a spectrum of microbes. However, the information regarding the mechanisms and structure-activity relationships remains elusive. The present review also focuses on the possible mechanisms of natural compounds based on their structure- activity relationships for incorporating polyphenolic compounds in the drug-development processes. Besides this work, polyphenols could reduce drug dosage and may diminish the unhidden or hidden side effects of antibiotics. Pre-clinical findings have provided strong evidence that polyphenolic compounds, individually and in combination with already approved antibiotics, work well against the development of resistance. However, more studies must focus on in vivo results, and clinical research needs to specify the importance of polyphenol-based antibacterials in clinical trials.

The therapeutic potential of hemp seed oil as Nasya in the management of insomnia: a literature review

Abstract The significance of getting sufficient sleep for maintaining good health and wellbeing is widely known. The American Psychiatric Association classifies insomnia as the most common sleep–wake disorder characterized by difficulty with sleep quality, timing, and quantity. The residual effects and the social stigma associated with the use of sedative drugs incline patients toward seeking alternative therapy. Ayurveda presents an exhaustive elucidation of the etiology, manifestations, and therapeutic modalities concerning insomnia. Among the extensively prescribed Panchakarma (the five-fold bio-purification process) interventions for insomnia management, Nasya (instillation of oils, powders, or juices through the nasal route) holds a significant position. Nasya is considered an effective way to directly deliver medicines to the brain by bypassing the blood–brain barrier through olfactory and trigeminal nerve pathways. Anandkand, an important book on Indian alchemy, mentions various formulations of hemp, including the use of hemp seed oil (Vijaya Beej Tail) for Nasya. A narrative analysis of hemp seed oil Nasya for insomnia was conducted using Ayurvedic texts and electronic databases. Although valued for its nutraceutical properties, there is limited clinical data on its effectiveness in treating insomnia. No relevant clinical studies were found for its use in treatment of insomnia, but some preclinical and clinical studies exist for other conditions. The presence of a perfect proportion of omega-3 to omega-6 fatty acids, coupled with its antioxidant properties and the existence of preclinical findings suggesting the sedative and anti-anxiety effects of hemp seed extracts by influencing the benzodiazepine receivers linked to gamma-aminobutyric acid, makes it a choice for Nasya therapy in clinically managing insomnia. A significant enhancement in scientific research efforts is imperative to maximize its potential utilization.

Mild exercise plus levothyroxine ameliorate deficits of spatial navigation, anxiety profile, and hippocampal BDNF in hypothyroid male offspring rats.

Levothyroxine (LEV) monotherapy cannot completely improve cognitive and behavioral impairments induced by hypothyroidism, whereas a combination therapy of exercise and LEV may ameliorate these deficits. This study aimed to determine the effects of mild-intensity forced exercise and LEV treatment on the anxiety profile and cognitive functions in male offspring of hypothyroid dams. Twenty-four female rats (mothers) were randomly divided into sham (healthy) and hypothyroidism groups and then placed with male rats to mate. The presence of vaginal plaque confirmed pregnancy (gestational day, GD 0). 6-propyl-2-thiouracil (PTU, 100ppm) was added to the drinking water of the hypothyroidism group from GD 6 to the 21st postnatal day (PND). The sham group received tap water. On PND 21, serum T4 levels of mothers, and 10 pups were measured to confirm hypothyroidism. Sixty-four male pups were left undisturbed for 30 days and then were divided into eight groups that received saline or LEV (50μg/kg, i.p.) with or without forced mild-intensity exercise. After 14 days of interventions, anxiety-like behaviors, spatial learning and memory, and hippocampal brain-derived neurotrophic factor (BDNF) levels were evaluated. A pre and postnatal PTU-induced model of hypothyroidism increased anxiety-like behaviors, impaired spatial learning and memory, and decreased hippocampal BDNF levels in male offspring rats. LEV alone increased BDNF levels and improved spatial learning. Exercise alone increased BDNF levels, improved spatial learning and memory, and decreased anxiety-like behaviors. Exercise plus LEV more effectively improved anxiety-like behaviors and spatial learning than exercise or LEV alone. Practically, these pre-clinical findings highlight the importance of the combination of exercise and LEV regimen in treating patients with hyperthyroidism.

Impaired cognition in narcolepsy: clinical and neurobiological perspectives.

In addition to well-known symptoms such as sleepiness and cataplexy, many people with narcolepsy have impaired cognition, reporting inattention, poor memory, and other concerns. Unfortunately, research on cognition in narcolepsy has been limited. Strong evidence demonstrates difficulties with sustained attention, but evidence for executive dysfunction and impaired memory is mixed. Animal research provides some insights into how loss of the orexin neurons in narcolepsy type 1 may give rise to impaired cognition via dysfunction of the prefrontal cortex, and cholinergic and monoaminergic systems. This paper reviews some of these clinical and preclinical findings, provides a neurobiological framework to understand these deficits, and highlights some of the many key unanswered questions.

Centralizing the Knowledge and Interpretation of Pain in Chemotherapy-Induced Peripheral Neuropathy: A Paradigm Shift towards Brain-Centric Approaches.

Chemotherapy-induced peripheral neuropathy (CIPN) is a side effect of cancer treatment, often linked with pain complaints. Patients report mechanical and thermal hypersensitivity that may emerge during chemotherapy treatment and may persist after cancer remission. Whereas the latter situation disturbs the quality of life, life itself may be endangered by the appearance of CIPN during cancer treatment. The causes of CIPN have almost entirely been ascribed to the neurotoxicity of chemotherapeutic drugs in the peripheral nervous system. However, the central consequences of peripheral neuropathy are starting to be unraveled, namely in the supraspinal pain modulatory system. Based on our interests and experience in the field, we undertook a review of the brain-centered alterations that may underpin pain in CIPN. The changes in the descending pain modulation in CIPN models along with the functional and connectivity abnormalities in the brain of CIPN patients are analyzed. A translational analysis of preclinical findings about descending pain regulation during CIPN is reviewed considering the main neurochemical systems (serotoninergic and noradrenergic) targeted in CIPN management in patients, namely by antidepressants. In conclusion, this review highlights the importance of studying supraspinal areas involved in descending pain modulation to understand the pathophysiology of CIPN, which will probably allow a more personalized and effective CIPN treatment in the future.

Navigating immunotherapy for ovarian cancer: current landscape and future perspectives

Ovarian cancer (OC) is the leading cause of death related to gynecologic malignancies, with recurrence occurring frequently despite significant advances in surgical interventions and chemotherapy. Therefore, novel therapies are necessary to improve the long-term prognosis of the disease. Immunotherapy holds promise in OC treatment by harnessing the potential of the immune system to combat neoplastic cells. The effectiveness of immunotherapy has been demonstrated in numerous cancers and subsequently integrated into clinical practice. However, despite initial preclinical findings suggesting an immunogenic microenvironment in OC, immune checkpoint inhibitors have not shown significant outcomes in clinical studies thus far. Further investigation is needed to fully understand the role of immunity in OC and to develop more effective therapeutic strategies, including combinatorial approaches and the identification of predictive biomarkers for more accurate patient selection for immunotherapy.

Neuroprotective Effects of Olive Oil: A Comprehensive Review of Antioxidant Properties.

Neurodegenerative diseases are a significant challenge to global healthcare, and oxidative stress plays a crucial role in their development. This paper presents a comprehensive analysis of the neuroprotective potential of olive oil, with a primary focus on its antioxidant properties. The chemical composition of olive oil, including key antioxidants, such as oleuropein, hydroxytyrosol, and oleocanthal, is systematically examined. The mechanisms by which these compounds provide neuroprotection, including counteracting oxidative damage and modulating neuroprotective pathways, are explored. The neuroprotective efficacy of olive oil is evaluated by synthesizing findings from various sources, including in vitro studies, animal models, and clinical trials. The integration of olive oil into dietary patterns, particularly its role in the Mediterranean diet, and its broader implications in neurodegenerative disease prevention are also discussed. The challenges in translating preclinical findings to clinical applications are acknowledged and future research directions are proposed to better understand the potential of olive oil in mitigating the risk of neurodegenerative conditions. This review highlights olive oil not only as a dietary component, but also as a promising candidate in preventive neurology, advocating for further investigation in the context of neurodegenerative diseases.

The role of the gut microbiome in disorders of gut–brain interaction

Disorders of Gut‐Brain Interaction (DGBI) are widely prevalent and commonly encountered in gastroenterology practice. While several peripheral and central mechanisms have been implicated in the pathogenesis of DGBI, a recent body of work suggests an important role for the gut microbiome. In this review, we highlight how gut microbiota and their metabolites affect physiologic changes underlying symptoms in DGBI, with a particular focus on their mechanistic influence on GI transit, visceral sensitivity, intestinal barrier function and secretion, and CNS processing. This review emphasizes the complexity of local and distant effects of microbial metabolites on physiological function, influenced by factors such as metabolite concentration, duration of metabolite exposure, receptor location, host genetics, and underlying disease state. Large‐scale in vitro work has elucidated interactions between host receptors and the microbial metabolome but there is a need for future research to integrate such preclinical findings with clinical studies. The development of novel, targeted therapeutic strategies for DGBI hinges on a deeper understanding of these metabolite‐host interactions, offering exciting possibilities for the future of treatment of DGBI.

Discovery of JNJ-74856665: A Novel Isoquinolinone DHODH Inhibitor for the Treatment of AML.

Acute myelogenous leukemia (AML), a heterogeneous disease of the blood and bone marrow, is characterized by the inability of myeloblasts to differentiate into mature cell types. Dihydroorotate dehydrogenase (DHODH) is an enzyme well-known in the pyrimidine biosynthesis pathway and preclinical findings demonstrated that DHODH is a metabolic vulnerability in AML as inhibitors can induce differentiation across multiple AML subtypes. As a result of virtual screening and structure-based drug design approaches, a novel series of isoquinolinone DHODH inhibitors was identified. Further lead optimization afforded JNJ-74856665 as an orally bioavailable, potent, and selective DHODH inhibitor with favorable physicochemical properties selected for clinical development in patients with AML and myelodysplastic syndromes (MDS).

Sodium-Glucose Co-Transporter-2 Inhibitor Empagliflozin Attenuates Sorafenib-Induced Myocardial Inflammation and Toxicity.

Environmental antineoplastics such as sorafenib may pose a risk to humans through water recycling, and the increased risk of cardiotoxicity is a clinical issue in sorafenib users. Thus, developing strategies to prevent sorafenib cardiotoxicity is an urgent work. Empagliflozin, as a sodium-glucose co-transporter-2 (SGLT2) inhibitor for type 2 diabetes control, has been approved for heart failure therapy. Still, its cardioprotective effect in the experimental model of sorafenib cardiotoxicity has not yet been reported. Real-time quantitative RT-PCR (qRT-PCR), immunoblot, and immunohistochemical analyses were applied to study the effect of sorafenib exposure on cardiac SGLT2 expression. The impact of empagliflozin on cell viability was investigated in the sorafenib-treated cardiomyocytes using Alamar blue assay. Immunoblot analysis was employed to delineate the effect of sorafenib and empagliflozin on ferroptosis/proinflammatory signaling in cardiomyocytes. Ferroptosis/DNA damage/fibrosis/inflammation of myocardial tissues was studied in mice with a 28-day sorafenib ± empagliflozin treatment using histological analyses. Sorafenib exposure significantly promoted SGLT2 upregulation in cardiomyocytes and mouse hearts. Empagliflozin treatment significantly attenuated the sorafenib-induced cytotoxicity/DNA damage/fibrosis in cardiomyocytes and mouse hearts. Moreover, GPX4/xCT-dependent ferroptosis as an inducer for releasing high mobility group box 1 (HMGB1) was also blocked by empagliflozin administration in the sorafenib-treated cardiomyocytes and myocardial tissues. Furthermore, empagliflozin treatment significantly inhibited the sorafenib-promoted NFκB/HMGB1 axis in cardiomyocytes and myocardial tissues, and sorafenib-stimulated proinflammatory signaling (TNF-α/IL-1β/IL-6) was repressed by empagliflozin administration. Finally, empagliflozin treatment significantly attenuated the sorafenib-promoted macrophage recruitments in mouse hearts. In conclusion, empagliflozin may act as a cardioprotective agent for humans under sorafenib exposure by modulating ferroptosis/DNA damage/fibrosis/inflammation. However, further clinical evidence is required to support this preclinical finding.

Neuroprotective Potentials of Berberine in Rotenone-Induced Parkinson's Disease-like Motor Symptoms in Rats.

Rotenone (RTN) induces neurotoxicity and motor dysfunction in rats, mirroring the pathophysiological traits of Parkinson's disease (PD), including striatal oxidative stress, mitochondrial dysfunction, and changes in neural structure. This makes RTN a valuable model for PD research. Berberine (BBR), an isoquinoline alkaloid recognized for its antioxidative, anti-inflammatory, and neuroprotective properties, was evaluated for its ability to counteract RTN-induced impairments. Rats received subcutaneous RTN at 0.5 mg/kg for 21 days, resulting in weight loss and significant motor deficits assessed through open-field, bar catalepsy, beam-crossing, rotarod, and grip strength tests. BBR, administered orally at 30 or 100 mg/kg doses, one hour prior to RTN exposure for the same duration, effectively mitigated many of the RTN-induced motor impairments. Furthermore, BBR treatment reduced RTN-induced nitric oxide (NO) and lipid peroxidation (LPO) levels, bolstered antioxidative capacity, enhanced mitochondrial enzyme activities (e.g., succinate dehydrogenase (SDH), ATPase, and the electron transport chain (ETC)), and diminished striatal neuroinflammation and apoptosis markers. Notably, the co-administration of trigonelline (TGN), an inhibitor of the nuclear factor erythroid-2-related factor 2 (Nrf2) pathway, significantly attenuated BBR's protective effects, indicating that BBR's neuroprotective actions are mediated via the Nrf2 pathway. These results underscore BBR's potential in ameliorating motor impairments akin to PD, suggesting its promise in potentially delaying or managing PD symptoms. Further research is warranted to translate these preclinical findings into clinical settings, enhancing our comprehension of BBR's therapeutic prospects in PD.

Neural mechanisms of psychedelic visual imagery.

Visual alterations under classic psychedelics can include rich phenomenological accounts of eyes-closed imagery. Preclinical evidence suggests agonism of the 5-HT2A receptor may reduce synaptic gain to produce psychedelic-induced imagery. However, this has not been investigated in humans. To infer the directed connectivity changes to visual connectivity underlying psychedelic visual imagery in healthy adults, a double-blind, randomised, placebo-controlled, cross-over study was performed, and dynamic causal modelling was applied to the resting state eyes-closed functional MRI scans of 24 subjects after administration of 0.2 mg/kg of the serotonergic psychedelic drug, psilocybin (magic mushrooms), or placebo. The effective connectivity model included the early visual area, fusiform gyrus, intraparietal sulcus, and inferior frontal gyrus. We observed a pattern of increased self-inhibition of both early visual and higher visual-association regions under psilocybin that was consistent with preclinical findings. We also observed a pattern of reduced inhibition from visual-association regions to earlier visual areas that indicated top-down connectivity is enhanced during visual imagery. The results were analysed with behavioural measures taken immediately after the scans, suggesting psilocybin-induced decreased sensitivity to neural inputs is associated with the perception of eyes-closed visual imagery. The findings inform our basic and clinical understanding of visual perception. They reveal neural mechanisms that, by affecting balance, may increase the impact of top-down feedback connectivity on perception, which could contribute to the visual imagery seen with eyes-closed during psychedelic experiences.

CAR-T immunotherapy - recent advances and current challenges in cancer treatment: a review.

Adoptive cell therapy represents a modern immunotherapeutic approach utilizing immune cells as dynamic agents against cancer cells, often called "living drugs". In recent times, chimeric receptor antigen T cell (CAR-T cell) therapy has shown efficacy and promise in the immunotherapy of cancers, presenting a significant advancement in blood cancer treatment. However, despite its effectiveness in treating B-cell lymphoma, challenges persist with response variability, resistance, and adverse effects. This review focuses on recent advances and current challenges, limitations, and the related preclinical and clinical findings of cancer immunotherapy as well as solutions for increasing the safety and effectiveness of CAR-T cell therapy. Ongoing research focuses on exploring molecular and cellular processes post-infusion, developing "universal CAR-T lymphocytes" sourced from healthy donors as well as exploring alternative candidates like CAR-armored NK cells and CAR-NKT cells, which show promise due to their potent anti-tumour properties and diverse cytotoxic capabilities. The interplay of genetics with the immune system undoubtedly holds the potential for developing innovative treatments that could revolutionize cancer therapy in the future.

Effect of AFPGC immune-microenvironment and resistance to immunotherapy.

e16041 Background: Alpha-fetoprotein producing gastric cancer (AFPGC) is a rare subtype GC with high with high morbidity and mortality rates. Even though immunotherapy has become the cornerstone of first-line treatment, our previous results suggest that AFPGC was resistant to immunotherapy, standard regimen remains unclear. It is warranted to explore precision immunotherapy strategies for AFPGC. Methods: A retrospective cohort of 98 patients with gastric cancer receiving mono-immunotherapy was included. Kaplan-Meier survival plots for PFS and OS were generated based on the AFP levels. Log-rank tests were used to compare the survival curves. Chi-square test was used to analyze the differences in the efficacy of immunotherapy between patients with different levels of AFP. AFPGC in vivo models were constructed, and after in vivo administration, RNA-seq, flow cytometry, and Western blot were used to explore and validate the features of the AFPGC microenvironment and explore immunotherapy combination strategies. Results: Retrospectively analysis demonstrated that the response of mono-immunotherapy in AFPGC was inferior to that in non-AFPGC (ORR: 16.7% vs 29.3%; DCR: 33.0% vs 55.4%). The response of the subcutaneous transplant tumor model with AFP overexpression to PD-1 antibody was significantly reduced. Meanwhile, RNA-seq results from the secondary PD-1 antibody resistant model showed that the mRNA level of AFP was significantly upregulated in the resistant model. RNA-seq results from transplant tumors of AFPGC compared to nAFPGC revealed that the differentially expressed genes were significantly enriched in pathways related to neutrophil chemotaxis and angiogenesis. Flow cytometry confirmed that the proportion of neutrophils in AFPGC was significantly higher than that in nAFPGC. SB265610 (neutrophil chemokine receptor inhibitor) combined with PD-1 antibody and apatinib (anti-angiogenesis) plus PD-1 antibody were administrated in animal models. Both of the regimens could release the primary resistance to PD-1 antibody. Based on these preclinical findings, we designed and conducted a clinical study (NCT04609176) to explore the reponse of apatinib combined with PD-1 antibody in AFPGC. Primary endpoints were achieved and will be announced in the near future. Typical case is depicted as follows: A 79 years old male patients diagnosed with low-differentiated adenocarcinoma of GC, AFP: 135220 ng/ml. After fail in chemotherapy, patients were treated with third-line apatinib 250mg po d1-d21, PD-1 monoclonal antibody 200mg d1, q21d for 6 cycles. Patient was evaluated as partial response (PR) for 4 months and AFP sharply decreased to 945 ng/ml. Conclusions: AFPGC is resistant to PD-1 monoclonal antibody. Combined treatment with SB265610 or apatinib can alleviate or reverse the resistance, making it the most promising treatment regimen for AFPGC.

Erythrocyte-αPD-1 conjugates overcome resistance to checkpoint blockade immunotherapy: A first-in-human study.

2557 Background: While the immune checkpoint blockade (ICB) therapy has revolutionized the field of tumor therapy. the resistance remains a major challenge. We have previously developed WTX-212, an erythrocyte-antibody conjugate covalently linking anti-PD-1 antibody to erythrocyte membranes. Unlike conventional antibodies, WTX-212 exhibits natural accumulation in the spleen and remodels the splenic immune landscape in tumor-bearing mice. WTX-212 treatment efficiently activates CD8+ T cells in the spleen, which subsequently infiltrate into tumors and exhibit anti-tumor cytotoxicity. Additionally, activated T cells reduce the splenic reservoir of Myeloid-derived suppressor cells (MDSC) and those within tumors, further enhancing overall anti-tumor responses. Pre-clinical studies have demonstrated that WTX-212 can significantly suppress tumor growth in xenograft tumor models resistant to anti-PD-1 immunotherapies. A first-in-human (FIH) clinical trial is now investigating its potential in human cancer patients. Methods: The FIH trial (NCT05707325) is aimed to investigate the safety, pharmacokinetics and preliminary efficacy of WTX-212 in cancer patients with advanced malignancies. All of patients had previously received anti-PDs therapies and developed resistance to these treatments. By Feb 5th, 2024, the tumor lesions were assessed using RECIST v1.1 criteria. Blood and tumor samples were collected for correlative analysis. Results: 7 metastasized patients with various solid tumors, having undergone a median of 3.1 prior lines of therapy (ranging from 1-6), received WTX-212 monotherapy. None of patients treated with WTX-212 experienced treatment-related adverse events greater than Grade 3, indicating a high safety profile. WTX-212 was detectable in peripheral blood at the end of cycle in a dose dependent manner. Disease control was achieved in 5/7 patients (DCR=71%). Specifically, a patient with esophageal cancer, achieved a confirmed complete remission after 6-cycle treatment. Additionally, two patients, one with esophageal cancer (3L) and another with HPV-negative cervical cancer (4L), maintained stable disease for over 40 and 30 weeks, respectively. Consistent with our pre-clinical findings, a substantial reduction in MDSCs were observed in 6/7 patients (ranging from 24%-82%). Furthermore, a median 1.5-fold increase in T cells was noted in all patients in the peripheral blood after the 1st cycle of the treatment. Conclusions: WTX-212 treatment is safe and tolerable and shows promising clinical signs in cancer patients resistant to anti-PD-1 immunotherapy, supporting further investigation and exploration of WTX-212 monotherapy and combination therapy. Clinical trial information: NCT05707325 .