Gastric Epithelial Cells Research Articles

MiR-520f-3p blocks MNNG-induced gastric precancerous lesions via the KLF7/NFκB pathway

Studying the regulatory mechanism of gastric disease progression to gastric cancer (GC) is essential. miR-520f expression is down-regulated in GC and inhibits the proliferation of gastric cancer cells, suggesting that it is associated with the development of GC, but whether it plays a role in the gastric precancerous lesion (GPL) is unclear. This study aimed to investigate the effect of miR-520f-3p in the N-methyl-N′-nitro-N-nitrosoguanidine (MNNG)-induced GPL model and to elucidate the role of its downstream target gene Kruppel-like factor 7 (KLF7) in it. The experimental results showed that miR-520f-3p expression was down-regulated in the MNNG-induced GES-1 cell model, and overexpression of miR-520f-3p reversed the effects of MNNG on cell migration, invasion and epithelial-mesenchymal transition (EMT) -related protein expression. Meanwhile, overexpression of KLF7 attenuated the effect of miR-520f-3p on GPL. In a mouse GPL model, it was observed that MNNG elicited inflammation and EMT processes in mouse gastric tissues through the KLF7/ Nuclear Factor Kappa B (NFκB) pathway, and silencing KLF7 alleviated MNNG-induced gastric epithelial cell injury and gastric atrophy symptoms. These results provide a new perspective for understanding the development of GPL, and the development of new therapies targeting miR-520f-3p and KLF7 may provide new ideas for the prevention and treatment of gastric cancer.

IL-33 Accelerates Chronic Atrophic Gastritis through AMPK-ULK1 Axis Mediated Autolysosomal Degradation of GKN1.

Chronic atrophic gastritis (CAG) is a complex disease characterized by atrophy and inflammation in gastric mucosal tissue, especially with high expression of interleukins. However, the interaction and mechanisms between interleukins and gastric mucosal epithelial cells in CAG remain largely elusive. Here, we elucidate that IL-33 stands out as the predominant inflammatory factor in CAG, and its expression is induced by H. pylori and MNNG through the ROS-STAT3 signaling pathway. Furthermore, our findings reveal that the IL-33/ST2 axis is intricately involved in the progression of CAG. Utilizing phosphoproteomics mass spectrometry, we demonstrate that IL-33 enhances autophagy in gastric epithelial cells through the phosphorylation of AMPK-ULK1 axis. Notably, inhibiting autophagy alleviates CAG severity, while augmentation of autophagy exacerbates the disease. Additionally, ROS scavenging emerges as a promising strategy to ameliorate CAG by reducing IL-33 expression and inhibiting autophagy. Intriguingly, IL-33 stimulation promotes GKN1 degradation through the autolysosomal pathway. Clinically, the combined measurement of IL-33 and GKN1 in serum shows potential as diagnostic markers. Our findings unveil an IL-33-AMPK-ULK1 regulatory mechanism governing GKN1 protein stability in CAG, presenting potential therapeutic targets for its treatment.

Shaoyao Gancao Decoction Mitigates Helicobacter Pylori-Induced Chronic Atrophic Gastritis by Suppressing MAOB.

Helicobacter pylori (H. pylori) plays an important role in chronic atrophic gastritis (CAG). Interestingly, Shaoyao Gancao decoction (SGD), a traditional Chinese analgesic prescription, has the efficacy of relaxing spasms and relieving pain. Here, we aimed to identify whether SGD alleviates CAG and the underlying mechanism. A CAG mouse model was developed using H. pylori colonization and a high-salt diet. Histological staining was used to study the histopathological damage changes, and RT-qPCR assays the production of inflammatory responses in the gastric mucosa of mice. H. pylori and a high-salt diet induced gastric mucosal damage and apoptosis of gastric mucosal epithelial cells in mice, eliciting a significant inflammatory response. Treatment with SGD alleviated CAG-induced gastric mucosal damage, reduced apoptosis of gastric mucosal epithelial cells, and inhibited the inflammatory response. Bioinformatics was then used to construct the pharmacological network of SGD to explore its potential targets. SGD inhibited inflammatory response in mice with CAG by suppressing the expression of MAOB. Overexpression of MAOB impaired the therapeutic effect of SGD on inflammation in mice with CAG. Collectively, our findings indicated that SGD has the potential to alleviate CAG via downregulating MAOB.

Helicobacter pylori-Induced Angiopoietin-Like 4 Promotes Gastric Bacterial Colonization and Gastritis.

Helicobacter pylori infection is characterized as progressive processes of bacterial persistence and chronic gastritis with features of infiltration of mononuclear cells more than granulocytes in gastric mucosa. Angiopoietin-like 4 (ANGPTL4) is considered a double-edged sword in inflammation-associated diseases, but its function and clinical relevance in H. pylori-associated pathology are unknown. Here, we demonstrate both pro-colonization and pro-inflammation roles of ANGPTL4 in H. pylori infection. Increased ANGPTL4 in the infected gastric mucosa was produced from gastric epithelial cells (GECs) synergistically induced by H. pylori and IL-17A in a cagA-dependent manner. Human gastric ANGPTL4 correlated with H. pylori colonization and the severity of gastritis, and mouse ANGPTL4 from non-bone marrow-derived cells promoted bacteria colonization and inflammation. Importantly, H. pylori colonization and inflammation were attenuated in Il17a -/-, Angptl4 -/-, and Il17a -/- Angptl4 -/- mice. Mechanistically, ANGPTL4 bound to integrin αV (ITGAV) on GECs to suppress CXCL1 production by inhibiting ERK, leading to decreased gastric influx of neutrophils, thereby promoting H. pylori colonization; ANGPTL4 also bound to ITGAV on monocytes to promote CCL5 production by activating PI3K-AKT-NF-κB, resulting in increased gastric influx of regulatory CD4+ T cells (Tregs) via CCL5-CCR4-dependent migration. In turn, ANGPTL4 induced Treg proliferation by binding to ITGAV to activate PI3K-AKT-NF-κB, promoting H. pylori-associated gastritis. Overall, we propose a model in which ANGPTL4 collectively ensures H. pylori persistence and promotes gastritis. Efforts to inhibit ANGPTL4-associated pathway may prove valuable strategies in treating H. pylori infection.

Interleukin-8 genetic polymorphism and its relation to Helicobacter pylori infection and Helicobacter pylori-associated gastric diseases

Helicobacter pylori (H. pylori) infection has a variety of clinical outcomes, and host genetic factors play an important role in this process. Cytokines are important factors in mediating and controlling the inflammatory process during H. pylori infection. Interleukin-8 (IL-8) plays a critical role in the epithelial cell response to H. pylori infection and the development of H. pylori-related gastric disorders. The IL-8 gene has an A/T base pair polymorphism in the promoter region (-251), which has been linked to an increase in interleukin production by gastric epithelial cells. In this context, the goal of our study was to determine the polymorphism in the IL-8 gene and its relation to H. pylori infection and H. pylori-associated gastric diseases. Gastric biopsy specimens were collected from 44 patients with H. pylori infection and 29 patients without H. pylori infection. The rapid urease test and detection of the glmM gene were used to diagnose H. pylori infection. Polymerase chain reaction-restriction fragment length polymorphism was used to identify the polymorphism in the Il-8 gene (at position-251). The presence of the A/A and T/A genotypes of the IL-8 gene was found to be significantly associated with susceptibility to H. pylori infection (p = 0.012 and p = 0.004, respectively). Also, the IL-8 A allele was significantly associated with H. pylori infection in our study (p = 0.002). We did not find a significant association between IL-8 gene polymorphism and a higher risk of gastritis and peptic ulcer disease. In conclusion, IL-8 gene polymorphism at -251 position was significantly associated with H. pylori infection.

Protective effect of short-chain fructo-oligosaccharides from chicory on alcohol-induced injury in GES-1 cells via Keap1/Nrf2 and NLRP3 inflammasome signaling pathways.

Numerous studies have demonstrated that polysaccharides derived from chicory possess the ability to regulate host signaling and modify mucosal damage. Yet, the effect and mechanism of short-chain fructo-oligosaccharides (scFOS) on gastric mucosa remain unclear. Hence, the protective effect of three scFOS (1-Kestose, Nystose, and 1F-Fructofuranosylnystose) against ethanol-induced injury in gastric epithelial (GES-1) cells, and the underlying molecular mechanism involved was investigated in this study. Treatment with 7% ethanol decreased the cell viability of GES-1 cells, resulting in oxidative stress and inflammation. However, pretreatment with scFOS exhibited significant improvements in cell viability, and mitigated oxidative stress and inflammation. scFOS markedly elevated the protein expression of Nrf2, HO-1, SOD1 and SOD2, while suppressing the expression of Keap1. scFOS pretreatment could also maintain mitochondrial membrane potential balance and reduce apoptosis. In addition, scFOS was observed to reduce the protein level of NLRP3, Caspase-1 and ASC. In conclusion, scFOS served a preventive function in mitigating oxidative stress and inflammation in ethanol-exposed GES-1 cells through modulation of the Keap1/Nrf2 and NLRP3 inflammasome signaling pathways. Collectively, the results indicated that scFOS could significantly mitigate ethanol-induced gastric cell damage, suggesting its potential for safeguarding gastrointestinal health.

Expression and clinical significance of ECHS1 in gastric cancer.

Background: Gastric cancer (GC), as one of the most common malignant tumors and the 3rd primary cause of death by cancer globally, poses a great threat to public health. Despite many advancements have been achieved in current treatment avenues for GC, the 5-year survival rates of GC patients remain substandard. Short-chain enoyl-CoA hydratase (ECHS1) exerts pro- or anti-cancer activities in different cancer backgrounds. However, its clinical significance and biological role in GC remain vague and need further investigation. Methods: The expression of ECHS1 in GC tumors and adjacent normal tissues was examined using the GEPIA platform and clinical samples. The effects of ECHS1 on GC cell proliferation and migration were evaluated using colony formation and transwell migration assays. Results: ECHS1 was upregulated in GC tumor tissues in both mRNA and protein levels and increased ECHS1 was markedly linked with tumor location, depth of tumor invasion, lymph node metastasis (LNM), and tumor-node-metastasis (TNM) stage of GC patients. High ECHS1 expression was also linked with a shorter overal survival (OS), first progression (FP) and post progression survival (PPS). Further subgroup analysis showed that OS was significantly shorter in GC patients with high ECHS1 expression compared to those with low ECHS1 expression belonging to tumors with T3 stage, N2 stage or in instestinal Lauren subgroup. In addition, cytological experiments showed that there was higher ECHS1 expression in GC cell lines compared to the normal gastric epithelium (GES-1) cells, and ECHS1 can promote GC cell proliferation and migration in vitro. Conclusion: ECHS1 plays an oncogenic role in GC and might be a promising therapeutic target for GC.

Copper-Bearing Metal-Organic Framework with Mucus-Penetrating Function for the Multi-Effective Clearance of Mucosal Colonized Helicobacter pylori.

Helicobacter pylori colonizes over 50% of people worldwide. Biofilm formation through penetrating gastric mucus and resistance acquired by H. pylori markedly reduces the efficacy of traditional antibiotics. The present triple therapy and bismuth-based quadruple therapy inevitably causes intestinal flora disturbance and fails to address the excessive H. pylori-triggered inflammatory response. Herein, a mucus-permeable therapeutic platform (Cu-MOF@NF) that consists of copper-bearing metal-organic framework (Cu-MOF) loaded with nitrogen-doped carbon dots and naturally active polysaccharide fucoidan is developed. The experimental results demonstrate that Cu-MOF@NF can penetrate the mucus layer and hinder H. pylori from adhering on gastric epithelial cells of the stomach. Notably, released Cu2+ can degrade the polysaccharides in the biofilm and interfere with the cyclic growing mode of "bacterioplankton ↔ biofilm", thereby preventing recurrent and persistent infection. Compared with traditional triple therapy, the Cu-MOF@NF not only possesses impressive antibacterial effect (even include multidrug-resistant strains), but also improves the inflammatory microenvironment without disrupting the balance of intestinal flora, providing a more efficient, safe, and antibiotic-free new approach to eradicating H. pylori.

There Are No Insurmountable Barriers: Passage of the Helicobacter pylori VacA Toxin from Bacterial Cytoplasm to Eukaryotic Cell Organelle.

The Gram-negative bacterium Helicobacter pylori is a very successful pathogen, one of the most commonly identified causes of bacterial infections in humans worldwide. H. pylori produces several virulence factors that contribute to its persistence in the hostile host habitat and to its pathogenicity. The most extensively studied are cytotoxin-associated gene A (CagA) and vacuolating cytotoxin A (VacA). VacA is present in almost all H. pylori strains. As a secreted multifunctional toxin, it assists bacterial colonization, survival, and proliferation during long-lasting infections. To exert its effect on gastric epithelium and other cell types, VacA undergoes several modifications and crosses multiple membrane barriers. Once inside the gastric epithelial cell, VacA disrupts many cellular-signaling pathways and processes, leading mainly to changes in the efflux of various ions, the depolarization of membrane potential, and perturbations in endocytic trafficking and mitochondrial function. The most notable effect of VacA is the formation of vacuole-like structures, which may lead to apoptosis. This review focuses on the processes involved in VacA secretion, processing, and entry into host cells, with a particular emphasis on the interaction of the mature toxin with host membranes and the formation of transmembrane pores.

Mechanistic insights into the ameliorative effects of Xianglianhuazhuo formula on chronic atrophic gastritis through ferroptosis mediated by YY1/miR-320a/TFRC signal pathway

Ethnopharmacological relevanceXianglianhuazhuo formula (XLHZ) has a potential therapeutic effect on chronic atrophic gastritis (CAG). However, the specific molecular mechanism remains unclear. Aim of the studyTo evaluate the effect of XLHZ on CAG in vitro and in vivo and its potential mechanisms. MethodsA rat model of CAG was established using a composite modeling method, and the pathological changes and ultrastructure of gastric mucosa were observed. YY1/miR-320a/TFRC and ferroptosis-related molecules were detected. An MNNG-induced gastric epithelial cell model was established in vitro to evaluate the inhibitory effect of XLHZ on cell ferroptosis by observing cell proliferation, migration, invasion, apoptosis, and molecules related to ferroptosis. The specific mechanism of action of XLHZ in treating CAG was elucidated by silencing or overexpression of targets. ResultsIn vivo experiments showed that XLHZ could improve the pathological status and ultrastructure of gastric mucosa and inhibit ferroptosis by regulating the YY1/miR-320a/TFRC signaling pathway. The results in vitro demonstrated that transfection of miR-320a mimics inhibited cell proliferation, migration, and invasion while promoting cell apoptosis. MiR-320a targeted TFRC and inhibited ferroptosis. Overexpression of TFRC reversed the inhibitory effect of miR-320a overexpression on cell proliferation. The effect of XLHZ was consistent with that of miR-320a. YY1 targeted miR-320a, and its overexpression promoted ferroptosis. ConclusionXLHZ inhibited ferroptosis by regulating the YY1/miR-320a/TFRC signaling pathway, ultimately impeding the progression of CAG.

Ochratoxin A-enhanced glycolysis induces inflammatory responses in human gastric epithelium cells through mTOR/HIF-1α signaling pathway

Ochratoxin A (OTA) is a mycotoxin commonly found in several food commodities worldwide with potential nephrotoxic, hepatotoxic and carcinogenic effects. We previously showed for the first time that OTA treatment enhanced glycolysis in human gastric epithelium (GES-1) cells in vitro. Here, we found that OTA exposure activated inflammatory responses, evidenced by increasing of NF-κB signaling pathway-related protein (p-p65 and p-IκBα) expressions and elevating of inflammatory cytokine (IL-1β and IL-6) mRNA expressions in GES-1 cells. To elucidate the role of glycolysis in inflammatory effects triggered by OTA, we pretreated GES-1 cells with glycolysis inhibitor (2-deoxy-D-glucose, 2-DG) before OTA exposure. The result showed that 2-DG reduced the protein expressions of p-p65 and p-IκBα and alleviated the mRNA expressions of inflammatory cytokines in OTA-treated GES-1 cells. Furthermore, OTA activated the mTOR/HIF-1α pathway by increasing the protein expressions of p-mTOR, p-eIF4E and HIF-1α, and inhibition of mTOR with rapamycin or silencing HIF-1α with siRNA significantly attenuated OTA-enhanced glycolysis by reducing glycolysis related genes and thereby decreasing inflammatory effects of GES-1 cells. These results demonstrate that OTA activates inflammatory responses in GES-1 cells and this is controlled by mTOR/HIF-1α pathway-mediated glycolysis enhancement. Our findings provide a novel mechanistic view into OTA-induced gastric cytotoxicity.

Exploring In Vitro the Combination of Cistus × incanus L. and Castanea sativa Mill. Extracts as Food Supplement Ingredients against H. pylori Infection.

Cistus spp. have been traditionally used for inflammatory and infectious disorders, including gastrointestinal ailments, in the Mediterranean area. Among them, Cistus × incanus L. is one of the most frequently cited species in the literature for a variety of biological activities which include inflammatory diseases. Cistus spp. aerial parts are rich in polyphenols such as condensed and hydrolysable tannins, procyanidins, and flavonoids, which show gastroprotective activities. The purpose of the present study is to investigate the biological activities of a hydroalcoholic extract from Cistus × incanus L. aerial parts in gastric epithelial cells (GES-1) infected with H. pylori. The extracts inhibited IL-8 and NF-κB induced by H. pylori and showed antibacterial activity after simulated digestion. Since our previous paper reported interesting results on the ability of Castanea sativa Mill. leaf extract to decrease inflammatory conditions in H. pylori-infected gastric cells, the combination of Castanea sativa and Cistus × incanus extracts was also investigated, showing strong anti-inflammatory activity and inhibition of bacterial adhesion. This association of botanicals is proposed herein as a novel food supplement capable of counteracting gastric inflammatory conditions.

An overview of potential algae-derived bioactive compounds against urease-positive microorganisms

Urease (EC 3.5.1.5) is a virulence factor found in various microorganisms, including Helicobacter pylori, Proteus mirabilis, and Klebsiella pneumoniae. As a nickel-containing enzyme, urease plays the most significant role in the colonization and maintenance of microorganisms in host organisms, making it a potential target for the treatment of resistant urease-positive infections. Notably, urease positive pathogens pose significant public health concerns due to their association with gastric ulcers, gastritis, kidney stones, urinary tract infections, and other diseases. This review focuses on exploring ureases' structure and catalytic properties, with a special emphasis on H. pylori. Moreover, the other virulence factors of H. pylori, including flagella, outer membrane proteins, accessory proteins, cytotoxin-associated gene A (CagA), and vacuolating cytotoxin A (VacA), are discussed. Also, the adaptive mechanism of H. pylori, relying on urease to survive the acidic gastric environment, is explored, along with the detrimental effects of ammonium on gastric epithelial cells produced by urease. Urease inhibitors have garnered interest as potential therapeutic agents to reduce the complications of urease-positive microorganisms. In this context, natural bioactive compounds gain interest in developing alternative therapeutic strategies. Algae are rich in several biochemical compounds with various biological attributes, particularly antibacterial and anti-inflammatory properties. Numerous studies have explored to identify the novel perspective anti-H. pylori agents from different algae species. This review also provides insights into the potential of algal bioactive compounds as effective agents against urease-positive infections. The significance of exploring new therapeutic strategies to address H. pylori-induced diseases is highlighted, considering the emergence of antibiotic resistance and the need for improved therapeutic approaches.

Loss of keratin 23 enhances growth inhibitory effect of melatonin in gastric cancer

Loss of keratin 23 enhances growth inhibitory effect of melatonin in gastric cancer

SMPDL3B contributes to gastric adenocarcinoma cells progression by promoting the infiltration of M2 macrophages.

The common disease gastric adenocarcinoma (GAC) has a high morbidity and mortality, so there is an urgent need for research to explore new diagnostic markers and therapeutic targets. This investigation was carried out to investigate the expression of sphingomyelin phosphodiesterase acid-like 3b (SMPDL3B) in GAC and its effects on tumor progression. Samples were collected from patients who underwent radical gastrectomy from January 2021 to December 2022. Along with the normal gastric epithelial cell lines GES-1 and SGC-7901, the AGS, MGC-803, and MSN-45 human gastric cancer cell lines were used to confirm SMPDL3B expression. RT-qPCR, Western blot, immunohistochemical, cell proliferation, assay of wound healing, transwell migration assay, invasion assay, flow cytometry, and immune evaluation experiments were carried out. SMPDL3B was found to be substantially expressed in GAC, and this condition has a bad prognosis. By establishing SMPDL3B knockdown and overexpression of GAC cell lines, this study confirmed that SMPDL3B promoted tumor cell proliferation, migration, and invasion. Additional bioinformatics research revealed a connection between SMPDL3B and immune cell infiltration in the GAC immunological microenvironment, which enhanced tumor cell proliferation by promoting the infiltration content of M2 macrophages. This study determined the function of SMPDL3B for the clinical diagnosis, prediction, and novel management of GAC.

Nano-plastics and gastric health: Decoding the cytotoxic mechanisms of polystyrene nano-plastics size

Gastrointestinal diseases exert a profound impact on global health, leading to millions of healthcare interventions and a significant number of fatalities annually. This, coupled with escalating healthcare expenditures, underscores the need for identifying and addressing potential exacerbating factors. One emerging concern is the pervasive presence of microplastics and nano-plastics in the environment, largely attributed to the indiscriminate usage of disposable plastic items. These nano-plastics, having infiltrated our food chain, pose a potential threat to gastrointestinal health. To understand this better, we co-cultured human gastric fibroblasts (HGF) with polystyrene nano-plastics (PS-NPs) of diverse sizes (80, 500, 650 nm) and meticulously investigated their cellular responses over a 24-hour period. Our findings revealed PS particles were ingested by the cells, with a notable increase in ingestion as the particle size decreased. The cellular death induced by these PS particles, encompassing both apoptosis and necrosis, showcased a clear dependence on both the particle size and its concentration. Notably, the larger PS particles manifested more potent cytotoxic effects. Further analysis indicated a concerning reduction in cellular membrane potential, alongside a marked increase in ROS levels upon PS particles exposure. This suggests a significant disruption of mitochondrial function and heightened oxidative stress. The larger PS particles were especially detrimental in causing mitochondrial dysfunction. In-depth exploration into the PS particles impact on genes linked with the permeability transition pore (PTP) elucidated that these PS particles instigated an internal calcium rush. This surge led to a compromise in the mitochondrial membrane potential, which in tandem with raised ROS levels, further catalyzed DNA damage and initiated cell death pathways. In essence, this study unveils the intricate mechanisms underpinning cell death caused by PS particles in gastric epithelial cells and highlighting the implications of PS particles on gastrointestinal health. The revelations from this research bear significant potential to shape future healthcare strategies and inform pertinent environmental policies.

Quercetin ameliorates Helicobacter pylori-induced gastric epithelial cell injury by regulating specificity protein 1/lipocalin 2 axis in gastritis.

Helicobacter pylori (HP) infection is the main cause of most cases of gastritis. Quercetin has been shown to have anti-inflammatory, anti-bacterial, and antiviral activities and has been demonstrated to be involved in HP-induced gastric mucosa injury. Moreover, the secretory protein lipocalin-2 (LCN2) was elevated in HP-infected gastric mucosa. Thus, this work aimed to study the interaction between quercetin and LCN2 in HP-triggered gastric injury during gastritis. Human gastric epithelial cell line GES-1 cells were exposed to HP for functional experiments. Cell viability, apoptosis, and inflammation were evaluated by cell counting kit-8, flow cytometry, and enzyme-linked immunosorbent assay, respectively. Levels of genes and proteins were tested using quantitative reverse transcription polymerase chain reaction and western blotting analyses. The interaction between LCN2 and specificity protein 1 (SP1) was validated using chromatin immunoprecipitation assay and dual-luciferase reporter assay. Thereafter, we found quercetin treatment suppressed HP-induced GES-1 cell apoptotic and inflammatory injury and macrophage M1 polarization. LCN2 was highly expressed in HP-infected gastritis patients and HP-infected GES-1 cells, while quercetin reduced LCN2 expression in HP-infected GES-1 cells; moreover, LCN2 knockdown reversed HP-induced GES-1 cell injury and macrophage M1 polarization, and forced expression of LCN2 abolished the protective effects of quercetin on GES-1 cells under HP infection. Mechanistically, SP1 bound to LCN2 promoter and promoted its transcription. Also, SP1 overexpression counteracted the functions of quercetin on HP-stimulated GES-1 cells. In all, quercetin ameliorated HP-induced gastric epithelial cell apoptotic and inflammatory injuries, and macrophage M1 polarization via the SP1/LCN2 axis.

Abstract C028: A phase 1/2 study investigating the safety and efficacy of autologous TAC T cells in subjects with unresectable, locally advanced or metastatic claudin 18.2+ solid tumors

Abstract CLDN18.2 is a tight junction protein found in differentiated gastric epithelial cells which can become abnormally expressed in a number of solid malignancies. This exposure profile illustrates the potential of CLDN18.2 as a candidate for targeted therapy. To date, there are no approved therapeutic agents directed against this target but promising data exist using monoclonal antibodies and conventional chimeric antigen receptor (CAR) T therapy. The T cell antigen coupler (TAC) technology is an approach to modifying T cells ex vivo, which allows recognition and cytotoxicity of tumor cells by co-opting the natural T cell receptor. TAC T cells demonstrate a safer profile than CAR T treatments. TAC01-CLDN18.2 is an autologous T-cell product comprising T cells expressing CLDN18.2 TAC. This is a first-in-human study (NCT05862324) to investigate the safety and preliminary anti-tumor activity of TAC01-CLDN18.2 in CLDN18.2+/HER2- solid tumors. Subjects will undergo leukapheresis and may receive bridging anticancer therapy as appropriate during cell manufacturing. Prior to TAC01-CLDN18.2 infusion, subjects will undergo low-intensity lymphodepletion chemotherapy. In phase I dose escalation, TAC01-CLDN18.2 will be administered at increasing doses (Cohorts 1-3) in adult subjects after ≥2 lines of therapy using the classic 3+3 dose escalation study design. Subjects with pancreatic ductal adenocarcinoma (PDAC) may have been treated with 1 line of prior therapy. CLDN18.2 expression levels will be determined centrally using a clinical trial assay validated across relevant indications. Dose limiting toxicities will be assessed up to 28 days from TAC01-CLDN18.2 infusion. A second dose may be administered, according to preidentified clinical and safety criteria. In Phase II, dose expansion groups will further evaluate the efficacy, safety, and pharmacokinetics of the optimal TAC01-CLDN18.2 dose, with the option of redosing. Indications will include gastric and esophageal adenocarcinoma (group A), PDAC (group B) and ovarian and non-small cell lung cancer (group C) in subjects after ≥2 and <4 lines of prior therapy (subjects with PDAC may have been exposed to 1 therapy). Definitions of eligible CLDN18.2 expression levels will be based on retrospective analysis of data from Phase 1 in association with clinical efficacy. A Simon 2-stage design will be used to enroll ≤57 subjects in Group A and ≤22 subjects in Group C. Group B will be exploratory and will enroll ≤10 subjects with an opportunity of cohort enrichment based on clinical efficacy data. Citation Format: Benjamin Schlechter, Ecaterina Dumbrava, Samuel Saibil, Martin Gutierez, Syma Iqbal, Davendra Sohal, Maria Apostolopoulou, Kara Moss, Deyaa Adib, Daniel Olson. A phase 1/2 study investigating the safety and efficacy of autologous TAC T cells in subjects with unresectable, locally advanced or metastatic claudin 18.2+ solid tumors [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr C028.

Polphylipoprotein-induced autophagy mechanism with high performance in photodynamic therapy

Polphylipoprotein (PLP) is a recently developed nanoparticle with high biocompatibility and tumor selectivity, and which has demonstrated unprecedentedly high performance photosensitizer in photodynamic therapy (PDT) and photodynamic diagnosis. On the basis of these discoveries, PLP is anticipated to have a very high potential for PDT. However, the mechanism by which PLP kills cancer cells effectively has not been sufficiently clarified. To comprehensively understand the PLP-induced PDT processes, we conduct multifaceted experiments using both normal cells and cancer cells originating from the same sources, namely, RGM1, a rat gastric epithelial cell line, and RGK1, a rat gastric mucosa-derived cancer-like mutant. We reveal that PLP enables highly effective cancer treatment through PDT by employing a unique mechanism that utilizes the process of autophagy. The dynamics of PLP-accumulated phagosomes immediately after light irradiation are found to be completely different between normal cells and cancer cells, and it becomes clear that this difference results in the manifestation of the characteristic effect of PDT when using PLP. Since PLP is originally developed as a drug delivery agent, this study also suggests the potential for intracellular drug delivery processes through PLP-induced autophagy.

Val-Leu-Leu-Tyr (VLLY) Alleviates Ethanol-Induced Gastric Mucosal Cell Impairment by Improving Mitochondrial Fission.

Ethanolic gastric mucosal impairment is one of the most common disorders in the gastrointestinal system. In this study, we investigated the potential alleviating effects of sea cucumber peptides on Ges-1 impairment caused by ethanol and the associated mechanisms. The sea cucumber peptide VLLY could promote the proliferation and migration of healthy Ges-1 cells. After ethanol injury, VLLY peptide treatment could greatly promote the migration of Ges-1 cells, scavenge intracellular and mitochondrial ROS, reverse mitochondrial fission and F-actin depolymerization, and improve mitochondrial respiration. VLLY peptide restored mitochondrial dynamics by downregulating Drp1 and Fis1 and upregulating Mfn2 against excessive mitochondrial fission. In addition, the VLLY peptide maintained the mitochondrial membrane potential, ablated the leakage of cytochrome c to the cytoplasm, upregulated the expression of the antiapoptotic factor Bcl-XL, decreased the expression of the proapoptotic factors of Bax, BAD, and cleaved caspase-3, and finally blocked the mitochondria-related apoptotic pathway. These findings strongly suggested that sea cucumber peptides could promote proliferation and migration of healthy Ges-1 cells and reverse ethanol-induced excess mitochondrial fission and maintain mitochondrial homeostasis through the Fis1/Bax pathway, thereby improving ethanol-induced apoptosis. VLLY offers a new perspective for improving the ethanolic gastric mucosal epithelial cell injury.