MKN45 Gastric Cancer Cells Research Articles

Enhancing the Chemosensitivity of MKN-45 Gastric Cancer Cells to Docetaxel via B7H6 Suppression: A Novel Therapeutic Strategy

Purpose: Although chemotherapy is one of the standard treatments for gastric cancer, the disease’s resistance mechanisms continue to limit the survival rates. B7H6 (NCR3LG1), an immune checkpoint belonging to the B7 family, is significantly overexpressed in gastric cancer. This work investigated the possibility of using B7H6 suppression to improve the effectiveness of the widely used chemotherapy medication docetaxel. Materials and Methods: In this study, MKN-45 gastric cancer cells were transfected for 24 h with siRNA targeting B7H6, and then, docetaxel was added at optimal inhibitory doses (IC25 and IC50). To assess the impact of this combination therapy, cellular viability, proliferation, and migration were assessed using MTT assay, colony-forming unit assay, and wound-healing assay, respectively. Additionally, apoptosis and cell cycle status were evaluated by flow cytometry. Moreover, using qRT-PCR, the gene expression of B7H6 and indicators associated with apoptosis was also examined. Results: The sensitivity of MKN-45 cells to docetaxel was greatly increased by the siRNA-mediated knockdown of B7H6, resulting in a decrease in the drug’s IC50 value. When compared to each therapy alone, the combination of B7H6 siRNA plus docetaxel at IC50 levels exhibited a significant increase in apoptosis rate. The volume of cells arrested at the sub-G1 and G2-M phase was shown to rise when B7H6 siRNA transfection was combined with docetaxel. Furthermore, the combination treatment significantly decreased the ability of cells to migrate and form colonies. Conclusions: B7H6 suppression increases the susceptibility of MKN-45 gastric cancer cells to docetaxel treatment, resulting in decreased cellular proliferation and increased rates of apoptosis. The present work underscores the possibility of enhancing treatment results in gastric cancer by merging conventional chemotherapy with gene-silencing approaches.

Prevention of liver metastasis via the pharmacological suppression of AMIGO2 expression in tumor cells

AMIGO2 adheres to liver endothelium and induces liver metastasis. We revealed that genetically altering AMIGO2 expression in tumor cells affects their liver metastatic potential, depending on the AMIGO2 expression level. The aim of this study was to prevent liver metastasis by pharmacologically suppressing AMIGO2 expression. For screening, we used the mouse LV12 cells because of their affinity to adhere to liver endothelium and metastasize the liver owing to elevated AMIGO2 expression. Of the 285 compounds tested, 17 reduced AMIGO2 mRNA expression. We subsequently screened for compounds that inhibited tumor cell adhesion to liver endothelium and identified five compounds that inhibit three signaling pathways (MEK, JAK, and JNK). Treatment with these compounds inhibited liver metastasis of LV12 cells. Next, we used clinically available signal inhibitors (MEK inhibitor trametinib, JAK inhibitor ruxolitinib, and JNK inhibitor SP600125), and found that ruxolitinib inhibits AMIGO2 expression more stably. Furthermore, ruxolitinib inhibited the adhesion of LV12 cells to liver endothelium and suppressed liver metastasis. Using the MKN45 gastric cancer cells, we confirmed that ruxolitinib could prevent liver metastasis of human cancer cells. These results demonstrate that pharmacological inhibition of AMIGO2 expression in tumor cells is a promising novel strategy to prevent and control liver metastasis.

Triple-regulated conditionally replicating adenovirus for effective and safer treatment of peritoneal carcinomatosis

There is no effective therapy for peritoneal carcinomatosis derived from gastric cancer. An ideal conditionally replicating adenovirus (CRA) that selectively replicates in and kills cancer cells has not been developed for gastric cancer-derived peritoneal carcinomatosis. Using our platform technology of CRA regulated and treating tumors with multiple factors (m-CRA), we generated two types of survivin-responsive m-CRAs, Surv.m-CRA-CMVp and Surv.m-CRA-CEAp, consisting of E1A downstream of the survivin promoter, and the mutated E1B gene downstream of the human cytomegalovirus immediate early gene enhancer/promoter and carcinoembryonic antigen promoter, respectively. Survivin mRNA was expressed at high and undetectable levels in two gastric cancer cells and eleven normal cells, respectively. Carcinoembryonic antigen was expressed at high and very low levels in MKN-45 gastric cancer and normal PrEC cells, respectively, and was not detected in other cell types. While both Surv.m-CRA-CEAp and Surv.m-CRA-CMVp exhibited potent cytotoxic effects on MKN-45 cells in vitro, Surv.m-CRA-CEAp significantly reduced cytotoxicity to normal cells compared to Surv.m-CRA-CMVp. Control mice that received an intraperitoneal injection of MKN-45 cells gradually lost body weight and died of peritoneal carcinomatosis within 98 days. In contrast, all mice receiving Surv.m-CRA-CEAp or Surv.m-CRA-CMVp-infected MKN-45 cells increased their body weight and survived 120 days. In conclusion, the triple-regulated Surv.m-CRA-CEAp enhances cancer specificity (i.e., safety) without reducing the potent therapeutic effect for carcinoembryonic antigen-positive gastric cancer-derived peritoneal carcinomatosis. The modified E1B promoter strategy of CRA facilitates the development of novel CRAs for the effective and safe treatment of a variety of refractory cancers.

Can Enzymatic Modified Pectin in Mediterranean Fruits Be Therapeutic Against Stomach Cancer?

The aim of this study was to evaluate the cytotoxic effects of enzymatically modified pectin products derived from grapefruit, jujube, and kumquat on the MKN-45 gastric cancer cell line invitro. FTIR analysis revealed that the spectra of the pectins produced were comparable to those of commercial pectin and included the characteristic peaks identified in the literature. The galacturonic acid content was measured as 612 mg/g in grapefruit pectin, 544 mg/g in jujube pectin, and 704 mg/g in kumquat pectin. DSC analysis indicated that all pectin samples and their modifications exhibited one endothermic peak and one exothermic peak. Cytotoxicity assessments revealed that the enzymatically modified grapefruit pectin demonstrated significant cytotoxic effects across all tested concentrations, with 0.075 mg/mL being the most effective. For kumquat pectin, all tested concentrations showed cytotoxic properties, with 0.3, 0.15, and 0.075 mg/mL being the most effective. In the case of jujube pectin, cytotoxic effects were observed at all concentrations except for 1.2 mg/mL.

Inhibitory Effects of Royal Jelly and Its Functional Components on the Proliferation of MKN-28 Gastric Cancer Cells.

Royal jelly (RJ) is a natural food product with nutritional value and anticancer activity. However, their effects on gastric cancer are unclear. Here, we show that treatment with 5-320 μg/mL of RJ, ethanol extract (RJEE), and protein hydrolyzate (RJPH) decreased the viability of MKN-28 gastric cancer cells, with a half-maximal inhibitory concentration of 123.22 μg/mL for RJEE. RJ, RJEE, and RJPH increase the lactate dehydrogenase release rate and change the morphology of the cells, resulting in cell shrinkage, nucleoplasm condensation, and the formation of apoptotic bodies. RJ and its functional components stagnated the cell cycle in the G0/G1 phase, accompanied by the accumulation of reactive oxygen species, decreased mitochondrial membrane potential, and increased expression levels of p53 and p21 proteins, caspase-3 activation, and apoptosis. Therefore, RJ, RJEE, and RJPH have potential inhibitory effects on the proliferation of gastric cancer cells.

Effects of microencapsulated phenethyl isothiocyanate on gastrointestinal cancer cells and pathogenic bacteria

Gastrointestinal cancers remain a global health burden, demanding more effective prevention and treatments. Phenethyl isothiocyanate (PEITC), a compound derived from cruciferous vegetables, stands out as a promising nutraceutical agent due to its chemopreventive and therapeutic properties. However, its therapeutic translation remains limited mainly due to its poor water solubility and rapid metabolism. Herein, we encapsulated PEITC into biocompatible chitosan-based microparticles with an extra virgin olive oil core to improve its bioavailability and stability. Pure PEITC's biocompatibility and microencapsulated PEITC's stability and antibacterial activity were evaluated. The antibacterial activity analysis showed microencapsulated PEITC as a promising antibacterial agent against gastrointestinal pathogenic bacteria (two Gram-positive and two Gram-negative). The impact of both pure and microencapsulated PEITC was assessed on gastrointestinal cancer cells (MKN45 gastric cancer and SW48 colon cancer cell lines). PEITC exhibited threshold or hormetic dose-dependent toxicity in colon fibroblasts and decreased gastric cancer cells' migration capacity, enhanced upon encapsulation into microparticles. In addition, microencapsulated PEITC induced downregulation of phosphorylated AKT, FAK, and ERK1/2 proteins, disrupting motility signaling pathways and tubulin expression. These findings suggest that the delivery of PEITC via chitosan-based microparticles holds promise as a nutraceutical delivery strategy against gastrointestinal disorders that predispose to cancer.

Lenvatinib acts on platelet‑derived growth factor receptor β to suppress the malignant behaviors of gastric cancer cells.

Given the limited treatment options and high mortality rates associated with gastric cancer, there is a need to explore novel therapeutic options. The present study aimed to investigate the efficacy of lenvatinib, a multi-target tyrosine kinase inhibitor, in mitigating the progress of gastric cancer in vitro. Comprehensive analyses were conducted to assess the impact of lenvatinib on gastric cancer cells, focusing on the inhibition of viability, suppression of proliferation, induction of apoptosis and reduction of metastatic potential. The effects of lenvatinib on these activities were determined using 5-ethynyl-2'-deoxyuridine staining, colony formation assay, flow cytometry, western blotting, scratch assay and Transwell assay. In addition, bioinformatics analyses were employed to identify key regulatory targets of lenvatinib, with particular attention given to platelet-derived growth factor receptor β (PDGFRB). In addition, the effects of PDGFRB overexpression on the regulation of lenvatinib were explored. Lenvatinib demonstrated significant inhibitory effects on the viability, proliferation and metastatic capabilities of MKN45 and HGC27 gastric cancer cell lines. Bioinformatics analyses identified PDGFRB as a crucial target of lenvatinib, with its downregulation showing promise in enhancing overall survival rates of patients with gastric cancer. By contrast, PDGFRB overexpression reversed the effects of lenvatinib on cells. The present findings underscore the potential of lenvatinib as a promising therapeutic option in the treatment of gastric cancer. By elucidating its mechanism of action and identifying PDGFRB as a primary target, the present study may aid further clinical advancements.

γ-Tocotrienol enhances autophagy of gastric cancer cells by the regulation of GSK3β/β-Catenin pathway.

γ-Tocotrienol (γ-T3) is a major subtype of vitamin E, mainly extracted from palm trees, barley, walnuts, and other plants. γ-T3 has effects on anti-inflammation, anti-oxidation, and potential chemoprevention against malignancies. It is still uncompleted to understand the effect of γ-T3 on the inhibitory mechanism of cancer. This study aimed to investigate whether γ-T3 enhanced autophagy in gastric cancer and the underlying molecular mechanism. The results showed that γ-T3 (0-90 μmol/L) inhibited the proliferation of gastric cancer MKN45 cells and AGS cells, and arrested the cell cycle at the G0/G1 phase in a dose-dependent manner. Autophagy was increased in MKN45 cells treated with γ-T3 (0-45 μmol/L), especially at a dose of 30 μmol/L for 24 h. These effects were reversed by 3-methyladeninepretreatment. Furthermore, γ-T3 (30 μmol/L) also significantly downregulated the expression of pGSK-3β (ser9) and β-catenin protein in MKN45 cells, and γ-T3 (20 mg/kg b.w.) effectively decreased the growth of MKN45 cell xenografts in BABL/c mice. GSK-3β inhibitor-CHIR-99021 reversed the negative regulation of GSK-3β/β-Catenin signaling and autophagy. Our findings indicated that γ-T3 enhances autophagy in gastric cancer cells mediated by GSK-3β/β-Catenin signaling, which provides new insights into the role of γ-T3 enhancing autophagy in gastric cancer.

Characterization of MET Alterations in 37 Gastroesophageal Cancer Cell Lines for MET-Targeted Therapy.

Capmatinib and savolitinib, selective MET inhibitors, are widely used to treat various MET-positive cancers. In this study, we aimed to determine the effects of these inhibitors on MET-amplified gastric cancer (GC) cells. Methods: After screening 37 GC cell lines, the following cell lines were found to be MET-positive with copy number variation >10: SNU-620, ESO51, MKN-45, SNU-5, and OE33 cell lines. Next, we assessed the cytotoxic response of these cell lines to capmatinib or savolitinib alone using cell counting kit-8 and clonogenic cell survival assays. Western blotting was performed to assess the effects of capmatinib and savolitinib on the MET signaling pathway. Xenograft studies were performed to evaluate the in vivo therapeutic efficacy of savolitinib in MKN-45 cells. Savolitinib and capmatinib exerted anti-proliferative effects on MET-amplified GC cell lines in a dose-dependent manner. Savolitinib inhibited the phosphorylation of MET and downstream signaling pathways, such as the protein kinase B (AKT) and extracellular signal-regulated kinase (ERK) pathways, in MET-amplified GC cells. Additionally, savolitinib significantly decreased the number of colonies formed on the soft agar and exerted dose-dependent anti-tumor effects in an MKN-45 GC cell xenograft model. Furthermore, a combination of trastuzumab and capmatinib exhibited enhanced inhibition of AKT and ERK activation in human epidermal growth factor receptor-2 (HER2)- and MET-positive OE33 cells. Targeting MET with savolitinib and capmatinib efficiently suppressed the growth of MET-amplified GC cells. Moreover, these MET inhibitors exerted synergistic effects with trastuzumab on HER2- and MET-amplified GC cells.

Effects of hypoxia on the growth of gastric cancer and the chemotherapeutic efficacy of 5-fluorouracil.

Hypoxia is an important cause of chemotherapy resistance in gastric cancer. However, little is known about the growth of gastric cancer under purely hypoxia conditions. This study aims to study the effect of hypoxia on the growth patterns of gastric cancer cells and explore the response of gastric cancer cells to the chemotherapeutic drug 5-fluorouracil (5-FU) in a hypoxic environment. Gastric cancer cells MKN45 were cultured under 1% oxygen hypoxia and conventional air conditions. An intervention group with the addition of the chemotherapeutic drug 5-FU was also established. The proliferation and apoptosis of gastric cancer cells under different oxygen conditions and intervention groups were detected using the cell counting kit-8 (CCK-8) method, JC-1 mitochondrial membrane potential assay, and Annexin-V/PI double staining method. Cell cycle changes were detected by flow cytometry, and mitochondrial changes were detected using electron microscopy. In the absence of 5-FU intervention, compared with the normoxia group, the hypoxia group showed higher rates of early and late apoptosis and higher cell death rates as indicated by the JC-1 mitochondrial membrane potential assay, Annexin-V/PI double staining, and CCK-8 results. Flow cytometry results showed that the cell cycle was arrested in the G0/G1 phase without progression. Electron microscopy revealed more severe mitochondrial destruction. However, with 5-FU intervention, the hypoxia group showed lower apoptosis rates, more cell cycle progression, and less mitochondrial destruction compared with the normoxia group. Hypoxic environments promote apoptosis and even death in gastric cancer cells, but hypoxia counteracts the efficacy of the chemotherapeutic drug 5-FU, which may contribute to 5-FU chemotherapy resistance.

Combination MEG3 lncRNA and Ciprofloxacin dramatically decreases cell migration and viability as well as induces apoptosis in GC cells in vitro.

Gastric cancer (GC) is a prominent cause of cancer-related mortality worldwide. Long noncoding RNA (lncRNA) maternal expression gene3 (MEG3) participates in numerous signaling pathways by targeting the miRNA-mRNA axis. Studies on human tumors have demonstrated that the antibiotic Ciprofloxacin induces cell cycle changes, programmed cell death, and growth suppression. In this study, we transfected MEG3 lncRNA and Ciprofloxacin into the MKN-45 GC cell line. qRT-PCR was employed to evaluate the effects on the specific microRNA and mRNA. The wound healing test, MTT assay, and flow cytometry were used to assess the impact of their administration on cell migration, viability, and apoptosis, respectively. Research showed that miR-147 expression fell even more after MEG3 lncRNA transfection, leading to an increase in B-cell lymphoma 2 (BCL-2) levels. Ciprofloxacin transfection did not significantly affect the axis, except for MEG3, which led to its slight upregulation. MEG3 lncRNA inhibited the migration of MKN-45 cells compared to the control group. When MEG3 lncRNA was coupled with Ciprofloxacin, there was a significant reduction in cell migration compared to untreated groups and controls. MTT assay and flow cytometry demonstrated that MEG3 lncRNA decreased cell viability and triggered apoptosis. Simultaneous administration of MEG3 lncRNA and Ciprofloxacin revealed a significant reduction in cell viability caused by increased apoptosis obtained from MTT or flow cytometry assays. Modulating the miR-147-BCL-2 axis decreases cell migration and survival while promoting cell death. In conclusion, combining MEG3 lncRNA with Ciprofloxacin may be an effective therapeutic approach for GC treatment by influencing the miR-14-BCl-2 axis, resulting in reduced cell viability, migration, and increased apoptosis.

Quercetin promotes ATG5-mediating autophagy-dependent ferroptosis in gastric cancer.

Quercetin has been documented to possess a multitude of pharmacological effects, encompassing antioxidant, antiviral, antimicrobial, and anti-inflammatory properties. Nevertheless, the exact molecular mechanisms responsible for the anti-tumor properties of quercetin remain to be fully explicated. To this end, quercetin was administered to gastric cancer cells (in vitro) AGS and MKN45, as well as BALB/c mice (in vivo). The proliferation ability of cells was evaluated using cholecystokinin octapeptide (CCK-8) and colony formation assays. The evaluation of ferroptosis involved the measurement of iron, malondialdehyde (MDA), and lipid reactive oxygen species. Autophagy and apoptosis were evaluated using immunofluorescence staining, western blotting, and flow cytometry analysis. Our findings indicate that quercetin significantly inhibited cell viability and tumor volume compared to the control group. Additionally, quercetin was found to decrease glutathione (GSH), malondialdehyde, and reactive oxygen species (ROS) levels while suppressing beclin1 and LC3B levels in cancer cells. Remarkably, the utilization of siATG5 was found to reverse all the aforementioned effects of quercetin. Ultimately, the effects of quercetin on gastric cancer were validated. In summary, our findings provide evidence that quercetin facilitates autophagy-mediated ferroptosis in gastric cancer.

Design and synthesis of chitosan/calcium lignosulfonate/Au NPs: Its performance for reduction of nitro compounds and in the treatment of cancer

This work introduces the preparation of a novel type of crosslinked polymers support based on calcium lignosulfonate-chitosan (CLS-CS) hydrogel with capping/reducing ability to encapsulated gold nanoparticles (CLS-CS/Au NPs). The morphology, structure and physicochemical properties of the prepared nanoparticles were characterized by different analytical techniques such as FT-IR, FE-SEM, TEM, EDX-elemental mapping study. The obtained results shown that CLS-CS/Au NPs prepared as spherical particles with sizes of 20–30 nm. The CLS-CS/Au NPs was applied as well for reduction of nitroarenes. The reduction of nitroarenes was obtained with good to high yields within short times. The related nanocatalyst was recovered for eight runs without significant loss of its catalytic performance. The MTT examination was conducted to check the anti-pancreatic cancer, anti-gastric cancer, anti-colorectal carcinoma, and cytotoxicity efficacies of the treated cells with CLS-CS/Au NPs over a 48-hour period on normal (HUVEC) and cancer cells. The IC50 values of the CLS-CS/Au NPs were found to be 169 µg/mL for HT-29 (colorectal carcinoma cell), 196 µg/mL for MKN45 (Gastric cancer cell), and 112 µg/mL for PANC-1 (Pancreatic cancer cell). The growth of malignant colorectal, gastric and pancreatic cells was found to decrease in a dose-dependent manner when exposed to CLS-CS/Au NPs. Following clinical research, CLS-CS/Au NPs shows promise as an effective treatment for colorectal, gastric and pancreatic cancers.

Overexpression and Downregulation of HOTAIR Influence the Stemness Markers in Gastric Cancer Cell Lines

Background: Several long non-coding RNAs are implicated in the development and metastasis of cancer. The non-coding RNA HOTAIR is known to play a significant role in the progression of various cancers. Objectives: This study aimed to assess the impact of HOTAIR dysregulation on stemness markers in AGS and MKN45 gastric cancer cell lines. Methods: Downregulation and upregulation of HOTAIR were induced using small interfering RNA (siRNA) and a HOTAIR overexpression vector, respectively. The surface stemness markers CD24 and CD44 were analyzed using flow cytometry. Additionally, the effects on the expression of two stemness markers, NANOG and P21, were investigated using Quantitative Reverse Transcription PCR (qRT-PCR). Results: Flow cytometry analysis showed that HOTAIR modulates the cell-surface expression of CD44 and CD24 in gastric cancer cells. Furthermore, dysregulation of HOTAIR significantly affected the expression of the genes P21 and NANOG. Conclusions: Our studies suggest that HOTAIR may regulate the stemness characteristics of gastric cancer cell lines.

Secondary metabolites from the deep-sea derived fungus Aspergillus terreus MCCC M28183.

Aspergillus fungi are renowned for producing a diverse range of natural products with promising biological activities. These include lovastatin, itaconic acid, terrin, and geodin, known for their cholesterol-regulating, anti-inflammatory, antitumor, and antibiotic properties. In our current study, we isolated three dimeric nitrophenyl trans-epoxyamides (1-3), along with fifteen known compounds (4-18), from the culture of Aspergillus terreus MCCC M28183, a deep-sea-derived fungus. The structures of compounds 1-3 were elucidated using a combination of NMR, MS, NMR calculation, and ECD calculation. Compound 1 exhibited moderate inhibitory activity against human gastric cancer cells MKN28, while compound 7 showed similar activity against MGC803 cells, with both showing IC50 values below 10 μM. Furthermore, compound 16 exhibited moderate potency against Vibrio parahaemolyticus ATCC 17802, with a minimum inhibitory concentration (MIC) value of 7.8 μg/mL. This promising research suggests potential avenues for developing new pharmaceuticals, particularly in targeting specific cancer cell lines and combating bacterial infections, leveraging the unique properties of these Aspergillus-derived compounds.

A prognostic marker LTBP1 is associated with epithelial mesenchymal transition and can promote the progression of gastric cancer.

LTBP1 is closely related to TGF-β1 function as an essential component, which was unclear in gastric cancer (GC). Harbin Medical University (HMU)-GC cohort and The Cancer Genome Atlas (TCGA) dataset were combined to form a training cohort to calculate the connection between LTBP1 mRNA expression, prognosis and clinicopathological features. Thetraining cohort was also used to verify the biological function of LTBP1 and its relationship with immune microenvironment and chemosensitivity. Inthe tissue microarrays (TMAs), immunohistochemical (IHC) staining was performed to observe LTBP1 protein expression. The correlation between LTBP1 protein expression level and prognosis was also analyzed, and a nomogram model was constructed. Western blotting (WB) was used in cell lines to assess LTBP1 expression. Transwell assays and CCK-8 were employed to assess LTBP1's biological roles. In compared to normal gastric tissues, LTBP1 expression was upregulated in GC tissues, and high expression was linked to a bad prognosis for GC patients. Based on a gene enrichment analysis, LTBP1 was primarily enriched in the TGF-β and EMT signaling pathways. Furthermore, high expression of LTBP1 in the tumor microenvironment was positively correlated with an immunosuppressive response. We also found that LTBP1 expression (p = 0.006) and metastatic lymph node ratio (p = 0.044) were independent prognostic risk factors for GC patients. The prognostic model combining LTBP1 expression and lymph node metastasis ratio reliably predicted the prognosis of GC patients. In vitro proliferation and invasion of MKN-45 GC cells were inhibited and their viability was decreased by LTBP1 knockout. LTBP1 plays an essential role in the development and progression of GC, and is a potential prognostic biomarker and therapeutic target for GC.

From mitochondria to tumor suppression: ACAT1's crucial role in gastric cancer.

Acetyl CoA acetyltransferase 1 (ACAT1), a mitochondrial enzyme, is mainly involved in the formation and decomposition of ketones, isoleucine, and fatty acids. Previous clinical studies showed that mutations in the ACAT1 gene lead to ketoacidosis, Notably the role of ACAT1 in human cancer' pathogenesis varies depending on cancer type, and its specific role in gastric cancer remains largely unknown. In the current study, we found that the expression of ACAT1 in primary late-stage gastric cancer tumor tissues was significantly lower than in early-stage tumors. This observation was further confirmed in high-grade gastric cancer cell line MKN45. The expression of CD44 and OCT4 was decreased, while CD24 expression was increased by overexpressing ACAT1 in MKN45 gastric cancer cells. Moreover, the ability of gastric cancer cells to form colonies on soft agar was also reduced by ACAT1 overexpression. Likewise, overexpression of ACAT1 inhibited epithelial mesenchymal transition (EMT) in gastric cancer cells evidenced by increased expression of the epithelial marker E-Cadherin, decreased expression of mesenchymal marker vimentin, and decreased expression levels of SNAI 1/3. In addition, ACAT1 overexpression inhibited cell migration and invasion, improved the response to 5-Fluorouracil (5-FU) and etoposide. In contrast, inhibition of ACAT1 activity promoted the proliferation of gastric cancer cells. The xenotransplantation results in nude mice showed that overexpression of ACAT1 in gastric cancer cells inhibited tumor growth in vivo. In addition, the low expression of ACAT1 in gastric cancer was further validated by searching public databases and conducting bioinformatic analyses. Mechanistically, bioinformatic analysis found that the inhibitory effect of ACAT1 in gastric cancer may be related to the Adipocytokine Signaling Pathway, Ppar Signaling Pathway, Propanoate Metabolism and P53 Signaling Pathway. Correlation analysis indicated ACAT1 mRNA expression was correlated with immune infiltrates. Collectively, our data show that ACAT1 induces pronounced inhibitory effects on gastric cancer initiation and development, which may impact future strategies to treat this aggressive cancer.

TRIB3 as a biomarker of gastric cancer cell sensitivity to chemotherapeutic agents running title: A protective role of TRIB3 on chemotherapy.

Understanding the role of TRIB3 in cellular chemotherapy responsiveness and survival could facilitate its development as a prognostic marker that could be used to improve chemotherapeutic efficiency against specific tumors. Therefore, the role of TRIB3 to reflect the cytotoxic abilities of chemotherapeutic agents was clarified in the tested gastric cancer cell lines. We have comprehensively investigated the protein expression of TRIB3 in three gastric cancer cell lines AGS, TMK-1, and MKN-45 cells treated with the anticancer drugs, 5-fluorouracil, cisplatin, and docetaxel. The Cell Count kit-8 was used to evaluate cell viability. Immunoblotting was performed to assay protein levels after drug treatment. Flow cytometry was carried out to evaluate the levels of sub-G1 cell population. Treatment of the tested gastric cancer cell lines dose-dependently decreased cell viability and protein levels of TRIB3 while increasing apoptosis. Overexpression of TRIB3 protects MKN-45 cells from endoplasmic reticulum stress-induced apoptosis but does not influence the induction of autophagy by anticancer drugs. In addition, overexpression of TRIB3 also rescued paroxetine-induced apoptosis and endoplasmic reticulum stress. Our previous and present results indicate that TRIB3 can protect gastric cancer cells against anticancer drug treatment and that downregulating TRIB3 may increase these cells' sensitivity to anticancer drugs. We thus suggest that the capability of anticancer drugs to downregulate TRIB3 can indicate tumors' potential susceptibility to these drugs.

Jolkinolide B Inhibits Gastric Cancer Growth by Targeting the PANoptosis Molecular Switch Caspase-8.

Background: To elucidate the mechanisms by which Jolkinolide B (JB), derived from Euphorbia fischeriana, suppresses gastric cancer (GC) development, given its known potent antitumor effects and the lack of detailed understanding of its impact and molecular processes in GC. Methods: The study utilized both cellular and animal models to investigate the effects of JB on GC. The GC cell lines AGS and MKN45 were used to assess JB's impact on cell growth, proliferation, migration, and invasion. Molecular techniques, including molecular docking and dynamics simulations, were employed to explore the binding interactions between JB and caspase-8. The inhibitor Z-IETD-FMK was used to examine the role of caspase-8 in JB-mediated PANoptosis. Xenograft tumor transplantation experiments were conducted to evaluate JB's effect on tumor growth and biotoxicity in vivo. Results: JB markedly inhibited the growth, proliferation, migration, and invasion of the AGS and MKN45 GC cell lines. It induced PANoptosis in GC cells by activating caspase-8, leading to increased expression of cleaved caspase-3/7 (apoptosis), GSDMD-N (pyroptosis), and p-RIPK1 and p-MLKL (necroptosis). Molecular docking and dynamics simulations revealed that JB binds effectively to caspase-8 with a binding free energy (ΔTotal) of -34.41 kcal/mol, suggesting specific binding-induced caspase-8 activation. The inhibition of caspase-8 by Z-IETD-FMK prevented JB-mediated PANoptosis. Additionally, JB significantly reduced tumor growth in xenograft models without causing biotoxicity. Conclusion: JB is a promising bioactive agent that inhibits gastric cancer growth through the activation of the PANoptosis pathway. This study highlights JB's potential as an effective therapeutic option for GC, underlining the importance of its binding interaction with caspase-8 and subsequent activation of apoptotic, pyroptotic, and necroptotic pathways.

Tribbles Genes in Gastric Cancer: A Tumor-Suppressive Role for TRIB2.

Tribbles pseudokinases (TRIB1-3) are important signaling modulators involved in several cancers. However, their function in gastric cancer (GC) remains undefined. GC is still a deadly disease since the lack of sensitive and specific biomarkers for early diagnosis and therapy response prediction negatively affects patients' outcome. The identification of novel molecular players may lead to more effective diagnostic and therapeutic avenues. Therefore, we investigated the role of TRIB genes in gastric tumorigenesis. Data mining of the TCGA dataset revealed that chromosomal instability (CIN) tumors have lower TRIB2 and higher TRIB3 expression versus microsatellite instability (MSI)-high tumors, while TRIB1 levels are similar in both tumor types. Moreover, in CIN tumors, low TRIB2 expression is significantly associated with aggressive stage IV disease. As no studies on TRIB2 in GC are available, we focused on this gene for further in vitro analyses. We checked the effect of TRIB2 overexpression (OE) on MKN45 and NCI-N87 CIN GC cell lines. In MKN45 cells, TRIB2 OE reduced proliferation and colony formation ability and induced G2/M arrest, while it decreased the proliferation and cell motility of NCI-N87 cells. These effects were not mediated by the MAPK pathway. Our results suggest a tumor-suppressive function of TRIB2 in GC with a CIN phenotype.