Gastric Cancer Cells Research Articles

PUS7-dependent pseudouridylation of ALKBH3 mRNA inhibits gastric cancer progression.

RNA pseudouridylation is a critical post-transcriptional modification that influences gene expression and impacts various biological functions. Despite its significance, the role of mRNA pseudouridylation in cancer remains poorly understood. This study investigates the impact of pseudouridine synthase 7 (PUS7)-mediated pseudouridylation of Alpha-ketoglutarate-dependent Dioxygenase alkB Homolog 3 (ALKBH3) mRNA in gastric cancer. Immunohistochemistry and Western blotting were used to assess PUS7 protein levels in human gastric cancer tissues. The relationship between PUS7 and gastric cancer progression was examined using 3D colony formation assays and subcutaneous xenograft models. Real-time quantitative PCR (RT-qPCR), Western blotting, and polysome profiling assays were conducted to investigate how PUS7 regulates ALKBH3. A locus-specific pseudouridine (Ψ) detection assay was used to identify Ψ sites on ALKBH3 mRNA. Our findings indicate a significant reduction of PUS7 in gastric cancer tissues compared to adjacent non-tumour tissues. Functional analyses reveal that PUS7 inhibits gastric cancer cell proliferation and tumour growth via its catalytic activity. Additionally, PUS7 enhances the translation efficiency of ALKBH3 mRNA by modifying the U696 site with pseudouridine, thereby attenuating tumour growth. Importantly, ALKBH3 functions as a tumour suppressor in gastric cancer, with its expression closely correlated with PUS7 levels in tumour tissues. PUS7-dependent pseudouridylation of ALKBH3 mRNA enhances its translation, thereby suppressing gastric cancer progression. These findings highlight the potential significance of mRNA pseudouridylation in cancer biology and suggest a therapeutic target for gastric cancer. PUS7 enhances the translation efficiency of ALKBH3 through its pseudouridylation activity on ALKBH3 mRNA, thereby inhibiting gastric tumourigenesis. The expression levels of PUS7 and ALKBH3 are significantly correlated in gastric tumours, which may be potential prognostic predictors and therapeutic targets for patients with gastric cancer.

Leaf extract from european olive (Olea europaea L.) post-transcriptionally suppresses the epithelial-mesenchymal transition and sensitizes gastric cancer cells to chemotherapy

The overall survival of patients with the advanced and recurrent gastric cancer (GC) remains unfavorable. In particular, this is due to cancer spreading and resistance to chemotherapy associated with the epithelial-mesenchymal transition (EMT) of tumor cells. EMT can be identified by the transcriptome profiling of GC for EMT markers. Indeed, analysis of the TCGA and GTEx databases (n= 408) and acohortof GC patients (n= 43) revealed that expression of theCDH2gene was significantly decreased in the tumors vs. non-tumor tissues and correlated with the overall survival of GC patients. Expression of the EMT-promoting transcription factors SNAILand ZEB1 was significantly increased in GC. These data suggest that targeting the EMT might be an attractive therapeutic approach for patients with GC. Previously, we demonstrated a potent anti-cancer activity of the olive leaf extract (OLE). However, its effect on the EMT regulation in GC remained unknown. Here, we showed that OLE efficiently potentiated the inhibitory effect of the chemotherapeutic agents 5-fluorouracil (5-FU) and cisplatin (Cis) on the EMT and their pro-apoptotic activity, as was demonstrated by changes in the expression of the EMT markers (E- and N-cadherins, vimentin, claudin-1) in GC cells treated with the aforementioned chemotherapeutic agents in the presence of OLE. Thus, culturing GC cells with 5-FU + OLE or Cis + OLE attenuated the invasive properties of cancer cells. Importantly, upregulation of expression of the apoptotic markers (PARP cleaved form) and increase in the number of cells undergoing apoptosis (Annexin V-positive) were observed for GC cells treated with a combination of OLE and 5-FU or Cis. Collectively, our data illustrate that OLE efficiently interferes with the EMT in GC cells and potentiates the pro-apoptotic activity of certain chemotherapeutic agents used for GC therapy.

Pan-cancer analysis of SERPINE1 with a concentration on immune therapeutic and prognostic in gastric cancer.

The serine protease inhibitor clade E member 1 (SERPINE1) is a key modulator of the plasminogen/plasminase system and has been demonstrated to promote tumor progression and metastasis in various tumours. However, although much literature has explored the cancer-promoting mechanism of SERPINE1, the pan-cancer analyses of its predictive value and immune response remain unexplored. The differential expression, and survival analysis of SERPINE1 expression in multiple cancers were analysed using The Cancer Genome Atlasand Genotype-Tissue Expression database. Kaplan-Meier (K-M) plotter and survival data analysis were used to analyze the prognostic value of SERPINE1 expression, including overall survival (OS), disease-specific survival, disease-free interval and progression-free interval and investigated the relationship of SERPINE1 expression with microsatellite instability. We further analysed the correlation between the expression of SERPINE1 and immune infiltration. The Kyoto Encyclopaedia of Genes and Genomes pathway was used for enrichment analysis, and the Gene Set Enrichment Analysis (GSEA) database was used to perform pathway analysis. Finally, invitro experiments demonstrated that knockdown or overexpression of SERPINE1 could alter the proliferation and migration of gastric cancer (GC) cells. The results indicated that SERPINE1 expression levels different significantly between cancer and normal tissues, meanwhile, it was highly expressed in various cancers. By analysing online data, it has been observed that the gene SERPINE1 exhibits heightened expression levels across a variety of human cancers, significantly impacting patient survival rates. Notably, the presence of SERPINE1 was strongly associated with decrease OS and disease-free survival in individuals diagnosed with GC. Furthermore, an observed link indicates that higher levels of SERPINE expression are associated with increased infiltration of immune cells in GC. Finally, invitro experiments showed that knockdown or overexpression of SERPINE1 inhibited the growth, and migration, of GC cells. SERPINE1expression potentially represents a novel prognostic biomarker due to its significant association with immune cell infiltration in GC. This study shows that SERPINE1 is an oncogene that participates in regulating the immune infiltration and affecting the prognosis of patients in multiple cancers, especially in GC. These findings underscore the importance of further investigating the role of SERPINE1 in cancer progression and offer a promising direction for the development of new therapeutic strategies.

CircRHBDD1 promotes immune escape via IGF2BP2/PD-L1 signaling and acts as a nanotherapeutic target in gastric cancer

BackgroundCircular RNAs (circRNAs) have been implicated in the development and progression of gastric cancer (GC). However, it remains unclear whether dysregulated circRNA affects immune escape and the efficacy of immunotherapy in GC. Our aim is to investigate the molecular mechanism of circRNA affecting GC immunotherapy and identify effective molecular therapeutic targets.MethodsThe differential expression profile of circRNAs was established through circRNA sequencing, comparing three paired GC tissues with their adjacent non-cancerous gastric tissues. The expression level of circRHBDD1 in GC tissues was then assessed using quantitative reverse transcription polymerase chain reaction (qRT-PCR). The biological characteristics of circRHBDD1 were verified through a series of experiments, including agarose gel electrophoresis assays, RNase R treatment, and actinomycin D experiments. The prognostic value of circRHBDD1 in GC was evaluated by conducting both univariate and multivariate survival analyses. Furthermore, loss- and gain-of-function approaches were utilized to investigate the impact of circRHBDD1 on GC immune escape. RNA-sequencing, immunoprecipitation, flow cytometry, and methylated RNA immunoprecipitation (meRIP) analysis were performed to elucidate the underlying molecular mechanisms.ResultsWe discovered that circRHBDD1 exhibited remarkably high expression levels in GC tissues and cell lines. Notably, the high expression of circRHBDD1 was significantly correlated with poor overall survival and disease-free survival among GC patients. Both in vitro and in vivo experiments revealed that circRHBDD1 upregulated the expression of PD-L1 and impeded the infiltration of CD8+ T cells. Further, we found that circRHBDD1 binds to IGF2BP2, disrupting the interaction between E3 ligase TRIM25 and IGF2BP2, and ultimately inhibiting IGF2BP2 ubiquitination and degradation. Intriguingly, IGF2BP2 enhances PD-L1 mRNA stability through m6A modification. Additionally, we developed Poly (lactide-co-glycolic acid) (PLGA)-Polyethylene glycol (PEG)-based nanoparticles loaded with circRHBDD1 siRNA. In vivo experiments validated that the combination of PLGA-PEG(si-circRHBDD1) and anti-PD-1 offers a safe and efficacious nano-drug regimen for cancer immunotherapy.ConclusionOur results demonstrated that circRHBDD1 promoted GC immune escape by upregulating the expression of PD-L1 and reprogramming T cell-mediated immune response. Inhibition of circRHBDD1 expression could potentially enhance the response of GC patients to immunotherapy, thus improving treatment outcomes. Additionally, the development of a nanodrug delivery system provides a feasible approach for future clinical applications.

Cancer-associated fibroblast-derived WNT5A promotes cell proliferation, metastasis, stemness and glycolysis in gastric cancer via regulating HK2

BackgroundGastric cancer (GC) is one of the most common cancers worldwide. Tumor microenvironment plays an important role in tumor progression. This study aims to explore the role of cancer-associated fibroblasts (CAFs) in GC and the underlying mechanism.MethodsCell viability, proliferation, invasion and migration were assessed by MTT, EdU, transwell and wound healing assays, respectively. Sphere formation assay was used to evaluate cell stemness. Glucose consumption, lactate production and ATP consumption were measured to assess glycolysis. In addition, The RNA and protein expression were detected by qRT-PCR and western blot. The interaction between wingless Type MMTV Integration Site Family, Member 5 A (WNT5A) and hexokinase 2 (HK2) was verified by Co-immunoprecipitation. The xenograft model was established to explore the function of CAFs on GC tumor growth in vivo.ResultsCAFs promoted the proliferation, metastasis, stemness and glycolysis of GC cells. WNT5A was upregulated in CAFs, and CAFs enhanced WNT5A expression in GC cells. Knockdown of WNT5A in either GC cells or CAFs repressed the progression of GC cells. In addition, WNT5A promoted HK2 expression, and overexpression of HK2 reversed the effect of WNT5A knockdown in CAFs on GC cells. Besides, knockdown of WNT5A in CAFs inhibits tumor growth in vivo.ConclusionCAF-derived WNT5A facilitates the progression of GC via regulating HK2 expression.

KPNA2 promotes the progression of gastric cancer by regulating the alternative splicing of related genes

RNA-binding proteins (RBPs) play critical roles in genome regulation. In this study, we explored the latent function of KPNA2, which is an essential member of the RBP family, in the regulation of alternative splicing (AS) in gastric cancer (GC). We analyzed the role of KPNA2 in regulating differential expression and AS via RNA sequencing (RNA-seq) and improved RNA immunoprecipitation sequencing (iRIP-seq). Clinical specimens were used to analyze the associations between KPNA2 expression and clinicopathological characteristics. CCK8 assays, transwell assays and wound healing assays were performed to explore the effect of KPNA2/WDR62 on GC cell progression. KPNA2 was shown to be highly expressed in GC cells and tissues and associated with lymph node metastases. KPNA2 promoted the proliferation, migration and invasion of GC cells and primarily regulated exon skipping, alternative 3's splice sites (A3SSs), alternative 5' splice sites (A5SSs), and cassette exons. We further revealed that KPNA2 participated in biological processes related to cell proliferation, and the immune response in GC via the regulation of transcription. In addition, KPNA2 preferentially bound to intron regions. Notably, KPNA2 regulated the A3SS AS mode of WDR62, and upregulation of WDR62 reversed the KPNA2 downregulation-induced inhibition of GC cell proliferation, migration and invasion. Finally, we discovered that the AS of immune-related molecules could be regulated by KPNA2. Overall, our results demonstrated for the first time that KPNA2 functions as an oncogenic splicing factor in GC that regulated the AS and differential expression of GC-related genes, and KPNA2 may be a potential target for GC treatment.

Transplanting mitochondria from gastric epithelial cells reduces the malignancy of gastric cancer

Mitochondria are essential for energy supplementation and metabolic homeostasis of cancer cells. Using mitochondria transplantation to reduce the malignancy of gastric cancer (GC) cells is herein proposed. In our study normal human gastric mucous epithelium cell line (GES-1) showed a lower mitochondrial membrane potential (MMP) compared to immortalized human vascular endothelial cell line (EAhy 926) and human gastric adenocarcinoma cell line (AGS). The transplantation of GES-1 mitochondria to AGS were confirmed both by confocal microscopy and flow cytometry. After transplanting GES-1 mitochondria, the AGS showed a reduced cell migration, and invasion without affecting cell viability and apoptosis. Investigating the expression of proteins involved in epithelial-mesenchymal-transition (EMT), transplanted GES-1 mitochondria reduced the expression of mesenchymal markers α-SMA, MMP-9, snail, vimentin and N-cadherin, whereas the epithelial markers E-cadherin and clauding-1 were not changed. The proteins implicated in the cell cycle such as cyclin B1 and D1 were decreased. In mice, inoculation with AGS carrying the transplanted GES-1 mitochondria resulted in smaller sized tumors. Further investigating the mitochondrial balance, the transplanted GES-1 mitochondria were more stably preserved compared to endogenous AGS mitochondria. The MMP, ATP production and mitochondrial mass decreased in GES-1 mitochondria and the mitophagic proteins LC3 II and PINK1 were up-regulated. In conclusion the decreased malignancy of AGS was a result of exogenous GES-1 mitochondria transplantation. This suggests for a therapy with low efficiency mitochondria transplantation in the treatment of cancer cells.

EIF2S2 transcriptionally upregulates HIF1α to promote gastric cancer progression via activating PI3K/AKT/mTOR pathway.

Eukaryotic translation initiation factor 2 subunit beta (EIF2S2) is a protein that controls protein synthesis under various stress conditions and is abnormally expressed in several cancers. However, there is limited insight regarding the expression and molecular role of EIF2S2 in gastric cancer. In this study, we identified the overexpression of EIF2S2 in gastric cancer by immunohistochemical (IHC) staining and found a positive correlation between EIF2S2 expression and shorter overall survival and disease-free survival. Functionally, we revealed that EIF2S2 knockdown suppressed gastric cancer cell proliferation and migration, induced cell apoptosis, and caused G2 phase cell arrest. Additionally, EIF2S2 is essential for in vivo tumor formation. Mechanistically, we demonstrated that EIF2S2 transcriptionally regulated hypoxia induicible factor-1 alpha (HIF1α) expression by NRF1. The promoting role of EIF2S2 in malignant behaviors of gastric cancer cells depended on HIF1α expression. Furthermore, the PI3K/AKT/mTOR signaling was activated upon EIF2S2 overexpression in gastric cancer. Collectively, EIF2S2 exacerbates gastric cancer progression via targeting HIF1α, providing a fundamental basis for considering EIF2S2 as a potential therapeutic target for gastric cancer patients.

HIGD1B, as a novel prognostic biomarker, is involved in regulating the tumor microenvironment and immune cell infiltration; its overexpression leads to poor prognosis in gastric cancer patients.

HIGD1B (HIG1 Hypoxia Inducible Domain Family Member 1B) is a protein-coding gene linked to the occurrence and progression of various illnesses. However, its precise function in gastric cancer (GC) remains unclear. The expression of HIGD1B is determined through the TCGA and GEO databases and verified using experiments. The association between HIGD1B and GC patients' prognosis was analyzed via the Kaplan-Meier (K-M) curve. Subsequently, the researchers utilized ROC curves to assess the diagnostic capacity of HIGD1B and employed COX analysis to investigate risk factors for GC. The differentially expressed genes (DEGs) were then subjected to functional enrichment analysis, and a nomogram was generated to forecast the survival outcome and probability of GC patients. Additionally, we evaluated the interaction between HIGD1B and the immune cell infiltration and predicted the susceptibility of GC patients to therapy. HIGD1B is markedly elevated in GC tissue and cell lines, and patients with high HIGD1B expression have a poorer outcome. In addition, HIGD1B is related to distinct grades, stages, and T stages. The survival ROC curves of HIGD1B and nomogram for five years were 0.741 and 0.735, suggesting appropriate levels of diagnostic efficacy. According to Cox regression analysis, HIGD1B represents a separate risk factor for the prognosis of gastric cancer (p<0.01). GSEA analysis demonstrated that the HIGD1B is closely related to cancer formation and advanced pathways. Moreover, patients with high HIGD1B expression exhibited a higher level of Tumor-infiltration immune cells (TIICs) and were more likely to experience immune escape and drug resistance after chemotherapy and immunotherapy. This study explored the potential mechanisms and diagnostic and prognostic utility of HIGD1B in GC, as well as identified HIGD1B as a valuable biomarker and possible therapeutic target for GC.

RETRACTION: "Effect of PLK1 Inhibition on Cisplatin-resistant Gastric Cancer Cells".

Z. Chen, Y. Chai, T. Zhao, P. Li, L. Zhao, F. He, Y. Lang, J. Qin, H. Ju,"Effect of PLK1 Inhibition on Cisplatin-resistant Gastric Cancer Cells," Journal of Cellular Physiology 234, no. 5 (2019): 5904-5914, https://doi.org/10.1002/jcp.26777. The above article, published online on 29 November 2018 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the authors; the journal Editor-in-Chief, Alexander Hutchison; and Wiley Periodicals LLC. The retraction has been agreed upon the authors' request. After the publication of their article, the authors discovered that the cell lines BGC-823 and SGC-7901 used in their study have been reported as contaminated [1, 2]. The authors have contacted the journal requesting the retraction of their article as these issues compromise the reliability of the research presented. The retraction is warranted, as the editors concur with the authors that the data is unreliable and the conclusions are invalid. REFERENCES [1] F. Ye, C. Chen, J. Qin, J. Liu, C. Zheng, "Genetic Profiling Reveals an Alarming Rate of Cross-contamination among Human Cell Lines Used in China," The FASEB Journal 29, no. 10 (2015): 4268-4272, https://doi.org/10.1096/fj.14-266718 [2] X. Bian, Z. Yang, H. Feng, H. Sun, Y. Liu, "A Combination of Species Identification and STR Profiling Identifies Cross-contaminated Cells from 482 Human Tumor Cell Lines," Scientific Reports 7, no. 1 (2017): 9774, https://doi.org/10.1038/s41598-017-09660-w.

Discovery of the Natural Bibenzyl Compound Erianin in Dendrobium Inhibiting the Growth and EMT of Gastric Cancer through Downregulating the LKB1-SIK2/3-PARD3 Pathway.

Erianin, a bibenzyl compound found in dendrobium extract, has demonstrated broad anticancer activity. However, its mechanism of action in gastric cancer (GC) remains poorly understood. LKB1 is a tumor-suppressor gene, and its mutation is an important driver of various cancers. Yet some studies have reported contradictory findings. In this study, we combined bioinformatics and in vitro and in vivo experiments to investigate the effect and potential mechanism of Erianin in the treatment of GC. The results show that LKB1 was highly expressed in patients' tumor tissues and GC cells, and it was associated with poor patient prognosis. Erianin could promote GC cell apoptosis and inhibit the scratch repair, migration, invasion, and epithelial-mesenchymal transition (EMT) characteristics. Erianin dose-dependently inhibited the expression of LKB1, SIK2, SIK3, and PARD3 but had no significant effect on SIK1. Erianin also inhibited tumor growth in CDX mice model. Unexpectedly, 5-FU also exhibited a certain inhibitory effect on LKB1. The combination of Erianin and 5-FU significantly improved the anti-tumor efficacy of 5-FU in the growth of GC cells and xenograft mouse models. In summary, Erianin is a potential anti-GC compound that can inhibit GC growth and EMT properties by targeting the LKB1-SIK2/3-PARD3-signaling axis. The synergistic effect of Erianin and 5-FU suggests a promising therapeutic strategy for GC treatment.

Relationship Between the Expression of Human Matricellular Protein 3 and the Pathological Features, Drug Resistance, and Prognosis of Gastric Cancer Based on Immunohistochemical Method

To observe the relationship between the expression of human matricellular protein 3 (MATN3) and the pathological features, drug resistance, and prognosis of gastric cancer based on immunohistochemical method. A total of 100 gastric cancer patients treated at the First Affiliated Hospital of Bengbu Medical College from January 2022 to December 2022 were included. MATN3 expression in gastric cancer tissues and paracancerous tissues was assessed by immunohistochemistry. The expression of MATN3 was compared across pathological features. Patients were divided into sensitive and resistant groups based on chemotherapy resistance, and MATN3 expression was compared between these groups. The relationship between MATN3 and recurrence-free survival (RFS) and overall survival (OS) of gastric cancer patients was analyzed using Kaplan-Meier survival curves. Univariate and multifactorial Cox regression analyses were used to analyze the factors affecting the prognosis of gastric cancer patients. Human gastric cancer cells MGC803 were transfected with MATN3. The cells were divided into a high expression group (LV-MATN3 group) and its control group (LV-NC group) and a low expression group (sh-MATN3 group) and its control group (sh-NC group). Cell proliferation was assessed using the CCK8 assay, cell migration and invasion were assessed using the Transwell assay, and MATN3 mRNA expression levels were measured using RT-qPCR. A nude mouse xenograft model was constructed by hypodermic injection of MGC-803 cells transfected with MATN3, and MATN3 mRNA expression levels in tumor tissues were measured using RT-qPCR. Immunohistochemical results showed a significantly higher rate of high MATN3 expression in gastric cancer tissues (64.00%, 64/100) compared to adjacent non-cancerous tissues (31.00%, 31/100) (P<0.05). High MATN3 expression was associated with age ≥60 years old, tumor location in the gastric body, tumor size ≥5 cm, lymph node metastasis (N1-N3), histological differentiation (moderate to high), tumor invasion depth (T3-T4), TNM stage (Ⅲ-Ⅳ), distant organ metastasis, recurrence, and mortality (P<0.05). Among patients with chemotherapy resistance, the high MATN3 expression rate was 79.49% (31/39) in the resistant group compared to 54.10% (33/61) in the sensitive group (P<0.05). Follow-up duration ranged from 11 to 22 months, with a 97.00% follow-up rate and 3 cases lost to follow-up. Kaplan-Meier survival curve analysis showed that patients with high MATN3 expression had significantly lower RFS and OS compared to those with low MATN3 expression (RFS: log-rank=17.291, P<0.001; OS: log-rank=21.719, P<0.001). Multivariate Cox analysis identified high MATN3 expression (hazard ratio [HR]=2.291, 95% confidence interval [CI]: 1.268-5.392), tumor location in the gastric body (HR=2.057, 95% CI: 1.441-5.666), lymph node metastasis (N1-N3) (HR=2.011, 95% CI: 1.010-2.274), tumor invasion depth (T3-T4) (H=2.977, 95% CI: 1.032-7.853), TNM stage Ⅲ-Ⅳ (HR=2.008, 95% CI: 1.049-3.902), and distant organ metastasis (HR=2.505, 95% CI: 1.529-5.000) as independent risk factors affecting RFS and OS (P<0.05). Cell and animal experiments demonstrated that compared to the LV-NC group, the LV-MATN3 group exhibited significantly higher cell proliferation, migration, and invasion (P<0.05), as well as increased tumor volume and MATN3 mRNA expression in tumor tissues (P<0.05). Conversely, the sh-MATN3 group showed significantly reduced cell proliferation, migration, and invasion, along with decreased tumor volume and MATN3 mRNA levels compared to the sh-NC group (P<0.05). MATN3 is highly expressed in gastric cancer tissues and is associated with various pathological features, drug resistance and poor prognosis. MATN3 holds potential as a diagnostic marker for poor prognosis and may play a role in the malignant behaviors of gastric cancer cells, including proliferation, migration, and invasion.

A Bioinformatic Assay of Quercetin in Gastric Cancer.

Gastric cancer (GC) remains a significant global health challenge, with high mortality rates, especially in developing countries. Current treatments are invasive and have considerable risks, necessitating the exploration of safer alternatives. Quercetin (QRC), a flavonoid present in various plants and foods, has demonstrated multiple health benefits, including anticancer properties. This study investigated the therapeutic potential of QRC in the treatment of GC. We utilized advanced molecular techniques to assess the impact of QRC on GC cells, examining its effects on cellular pathways and gene expression. Our findings indicate that QRC significantly inhibits GC cell proliferation and induces apoptosis, suggesting its potential as a safer therapeutic option for GC treatment. Further research is required to validate these results and explore the clinical applications of QRC in cancer therapy.

MARK4 promotes the malignant phenotype of gastric cancer through the MAPK/ERK signaling pathway

BackgroundMicrotubule affinity regulating kinase 4 (MARK4), which is overexpressed in various tumors, is involved in the regulation of cell division, proliferation, migration, and the cell cycle, and has been considered a potential marker for cancer; however, its mechanism of action in gastric cancer (GC) remains unclear. This study aimed to investigate the role of MARK4 in the proliferation, migration, and invasion of GC cell through the MAPK/ERK signaling pathway by targeting MARK4 knockdown. MethodsUsing The Cancer Genome Atlas data and clinical information, MARK4 expression and its relationship with prognosis were analyzed. Possible pathways involving MARK4 were explored using enrichment analysis. Western blotting and real-time quantitative polymerase chain reaction were used to detect MARK4 expression in GC. After targeted transfection of siRNA, the transfection efficiency of the experimental group was detected in AGS and HGC-27 cells. The effects of knockdown MARK4 on the proliferation, migration, and invasion of GC cells were verified using CCK-8, colony formation, wound healing, and transwell assays. Finally, the relationship between MARK4, the MAPK/ERK pathway, and epithelial-mesenchymal transition in GC was verified by western blotting. ResultsMARK4 expression was upregulated in GC and associated with poor prognosis in patients with GC. Enrichment analysis showed that MARK4 was involved in the activation of the MAPK signaling pathway. Western blotting results indicated that MARK4 overexpression promoted the proliferation, migration, and invasion of GC cells through the MAPK/ERK pathway. ConclusionMARK4 expression was upregulated in GC and promoted the proliferation, migration, and invasion of GC cells through the MAPK/ERK pathway.

Raddeanin A promotes the apoptosis of gastric cancer in conjunction with autophagy inhibitor Hydroxychloroquine via MAPK signaling pathway

PurposeGastric cancer (GC) is among the malignant cancers with the highest incidence and mortality worldwide. As GC is not very sensitive to current chemotherapy drugs, there is an urgent need to develop new effective drugs. Raddeanin A (RA) is extracted from the traditional Chinese medicine Anemone raddeana Regel, which has an anti-cancer effect. The purpose of this study was to explore the effects of RA on GC in vitro and in vivo. MethodsWe explored the targets of RA in GC through network pharmacology. MTT assay, flow cytometry, Western blotting, and other methods were used to detect the effects of RA on the proliferation, apoptosis, and autophagy of GC cells. After preconditioning with hydroxychloroquine (HCQ) and rapamycin, we observed the effects of RA-induced autophagy on apoptosis. We further verified the antitumor effect and safety of RA in vivo. Using SNU-1 xenograft tumor model in nude mice, tumor volume was observed and liver toxicity was observed by immunohistochemistry. ResultsMany cancer-related signaling pathways were visualized using Cytoscape software. Among them, the MAPK signaling pathway was one of the highest-ranked pathways. The MTT assay results suggested that RA could inhibit the proliferation of HGC-27 and SNU-1 cells effectively. Flow cytometry and Western blotting confirmed that RA could significantly induce apoptosis of HGC-27 and SNU-1 cells. Electron microscopy and Western blotting demonstrated that RA could induce autophagy of HGC-27 and SNU-1 cells. Further experiments suggested that HCQ, an autophagy inhibitor, could enhance the capacity of RA to induce apoptosis. In animal studies, we found that intraperitoneal injection of RA could effectively and safely inhibit gastric tumors. ConclusionsRA significantly inhibited the proliferation and induced autophagy and apoptosis of GC cells. In combination with HCQ, RA-induced apoptosis increased in vitro. The combined application of RA and autophagy inhibitors may serve as an added approach to the treatment of GC, but the underlying mechanism needs further exploration. In vivo, it was observed that RA has a good antitumor effect without increasing liver toxicity.

UBE2C regulates the KEAP1/NRF2 signaling pathway to promote the growth of gastric cancer by inhibiting autophagy

Gastric cancer (GC) is one of the most common malignant tumors in the world, ranking fourth in incidence and second in mortality among malignant tumors. In recent years, there has been some progress in biological treatment and targeted treatment for gastric cancer, but the prognosis for gastric cancer patients remains pessimistic, and the molecular mechanisms involved are not yet clear. In this study, bioinformatics analysis showed that Ubiquitin-conjugating enzyme E2C(UBE2C) was abnormally expressed in various types of cancer. Furthermore, UBE2C protein and mRNA expression was significantly elevated in gastric cancer tissues and cells. Silencing UBE2C significantly inhibited the proliferation and migration of gastric cancer cells. Mechanistically, UBE2C overexpression inhibited gastric cancer cell autophagy, leading to the accumulation of p62. Furthermore, immunoprecipitation results showed that UBE2C overexpression promoted the interaction between p62 and KEAP1, while inhibiting the binding of NRF2 to KEAP1, thereby weakening the ubiquitination and degradation of NRF2. In addition, the silencing of UBE2C leads to a reduction in the nuclear accumulation of NRF2. Importantly, the NRF2 activator TBHQ reversed the inhibition of gastric cancer cell proliferation and migration caused by the silencing of UBE2C. In summary, our study provides new insights into the molecular mechanisms of UBE2C in anti-cancer therapy.

Dextran sulfate inhibits proliferation and metastasis of human gastric cancer cells via miR-34c-5p

BackgroundGastric cancer (GC) is a malignant tumor with a high global mortality rate that is currently difficult to treat. Dextran sulfate (DS), a safe anti-tumor agent, can effectively inhibit the malignant biological behavior of gastric cancer; however, its mechanism of action is not fully understood. Therefore, this study aimed at elucidate the potential mechanisms of action. MethodsIn this study we used DS to intervene in lentivirus-transfected gastric cancer cells to observe the effect of DS on miR-34c-5p. RT-qPCR, CCK-8, clone formation assay, wound healing assay, transwell assay and western blot were used to examine whether DS affects the proliferation and metastasis of gastric cancer cells via miR-34c-5p. The results were validated using in vivo experiments. ResultsOur data confirmed that DS up-regulated miR-34c-5p expression in human gastric cancer cells. Moreover, DS intervention enhanced the inhibitory effect of miR-34c-5p over-expression on the proliferation, invasion, and migration of gastric cancer cells, and partially reversed the promotive effect of miR-34c-5p on the proliferation, invasion, and migration of gastric cancer cells. In addition, DS could affect the activation of the MAP2K1/ERK signaling pathway through the up-regulation of miR-34c-5p, thereby inhibiting the malignant biological behavior of gastric cancer. Finally, it was demonstrated that DS could also inhibit the expression of MAP2K1 in vivo, which in turn inhibits the activation of the ERK signaling pathway to exert anti-cancer effects. ConclusionDS may inhibit the proliferation and metastasis of gastric cancer cells by regulating miR-34c-5p, which may be a new option for clinical treatment.

Investigation of the Cytotoxicity of CAR-NK-92 Cells Targeting CEA Against Gastric Cancer Cells

Investigation of the Cytotoxicity of CAR-NK-92 Cells Targeting CEA Against Gastric Cancer Cells

Linoleic Acid Modulates the Expression of Metastatic and Angiogenic Markers MMP-2 and Talin-2 in Gastric Cancer Cell Line MKN-45.

Linoleic acid (LA) has modulatory effects on gastric cancer cell lines. This study aimed to investigate the effects of linoleic acid on the expression of metastatic and angiogenic molecular markers in gastric cancer cell line MKN-45. In this study performed in Tabriz, Iran in 2021, MKN-45 cells were treated with LA in the presence or absence of docetaxel. Total RNA was extracted, and cDNA synthesized from the cells before and after treatment. The expression levels of Talin-2 and MMP-2 genes and mir-20, mir-30, mir-126, and mir-194, were determined by quantitative real-time PCR. LA treatment reduced the expression levels of mir-126, mir-194, mir-30, and MMP-2, while increased the expression levels of Talin-2 mRNA. Docetaxel treatment could decrease the expression levels of mir-20, Talin-2, and MMP-2 mRNA levels while increasing the expression levels of mir-126, mir-194, and mir-30. Additionally, the combined treatment of MKN-45 cells with LA and docetaxel could reduce the expression levels of mir-20 and mir-126 and increased the expression levels of mir-194, mir-30, Talin-2, and MMP-2 mRNAs. Modulation of the expression levels of gastric cancer involved microRNAs, Talin-2, and MMP-2 may be a mechanism through which LA may exert its biological effects on GC cell line MKN-45. LA may have an antimetastatic effect by reducing the MMP-2 expression and pro-angiogenic effect through increasing Talin-2 expression levels.

Comprehensive landscape of integrator complex subunits and their association with prognosis and tumor microenvironment in gastric cancer.

The integrator complex (INT) is a multiprotein assembly in gene transcription. Although several subunits of INT complex have been implicated in multiple cancers, the complex's role in gastric cancer (GC) is poorly understood. The gene expressions, prognostic values, and the associations with microsatellite instability (MSI) of INT subunits were confirmed by GEO and The Cancer Genome Atlas (TCGA) databases. cBioPortal, GeneMANIA, TISIDB, and MCPcounter algorithm were adopted to investigate the mutation frequency, protein-protein interaction network, and the association with immune cells of INT subunits in GC. Additionally, in vitro experiments were performed to confirm the role of INTS11 in pathogenesis of GC. The mRNA expression levels of INTS2/4/5/7/8/9/10/11/12/13/14 were significantly elevated both in GSE183904 and TCGA datasets. Through functional enrichment analysis, the functions of INT subunits were mainly associated with snRNA processing, INT, and DNA-directed 5'-3' RNA polymerase activity. Moreover, these INT subunit expressions were associated with tumor-infiltrating lymphocytes and MSI in GC. In vitro experiments demonstrated that knockdown of the catalytic core INTS11 in GC cells inhibits cell proliferation ability. INTS11 overexpression showed opposite effects. Our data demonstrate that the INT complex might act as an oncogene and can be used as a prognosis biomarker for GC.