Target For Gastric Cancer Research Articles

Expression and significant roles of the long non-coding RNA CASC19/miR-491-5p/HMGA2 axis in the development of gastric cancer

BACKGROUND Gastric cancer (GC) is a common malignant tumor, long non-coding RNA and microRNA (miRNA) are important regulators that affect tumor proliferation, metastasis and chemotherapy resistance, and thus participate in tumor progression. CASC19 is a new bio-marker which can promote tumor invasion and metastasis. However, the mechanism by which CASC19 affects the progression of GC through miRNA is not clear. AIM To explore the role of the CASC19/miR-491-5p/HMGA2 regulatory axis in GC. METHODS To explore the expression and prognosis of CASC19 in GC through clinical samples, and investigate the effects of inhibiting CASC19 on the proliferation, migration, invasion and other functions of GC cells through cell counting Kit-8 (CCK-8), ethynyldeoxyuridine, Wound healing assay, Transwell, Western blot and flow cytometry experiments. The effect of miR-491-5p and HMGA2 in GC were also proved. The regulatory relationship between CASC19 and miR-491-5p, miR-491-5p and HMGA2 were validated through Dual-luciferase reporter gene assay and reverse transcription PCR. Then CCK-8, Transwell, Wound healing assay, flow cytometry and animal experiments verify the role of CASC19/miR-491-5p/HMGA2 regulatory axis. RESULTS The expression level of CASC19 is related to the T stage, N stage, and tumor size of patients. Knockdown of the expression of CASC19 can inhibit the ability of proliferation, migration, invasion and EMT conversion of GC cells, and knocking down the expression of CASC19 can promote the apoptosis of GC cells. Increasing the expression of miR-491-5p can inhibit the proliferation of GC cells, miR-491-5p mimics can inhibit EMT conversion, and promote the apoptosis of GC cells, while decreasing the expression of miR-491-5p can promote the proliferation and EMT conversion and inhibit the apoptosis of GC cells. The expression of HMGA2 in GC tissues is higher than that in adjacent tissues. At the same time, the expression level of HMGA2 is related to the N and T stages of the patients. Reducing the level of HMGA2 can promote cell apoptosis and inhibit the proliferation of GC cells. Cell experiments and animal experiments have proved that CASC19 can regulates the expression of HMGA2 through miR-491-5p, thereby affecting the biological functions of GC. CONCLUSION CASC19 regulates the expression of HMGA2 through miR-491-5p to affect the development of GC. This axis may serve as a potential biomarker and therapeutic target of GC.

Master Regulators of Causal Networks in Intestinal- and Diffuse-Type Gastric Cancer and the Relation to the RNA Virus Infection Pathway.

Causal networks are important for understanding disease signaling alterations. To reveal the network pathways affected in the epithelial-mesenchymal transition (EMT) and cancer stem cells (CSCs), which are related to the poor prognosis of cancer, the molecular networks and gene expression in diffuse- and intestinal-type gastric cancer (GC) were analyzed. The network pathways in GC were analyzed using Ingenuity Pathway Analysis (IPA). The analysis of the probe sets in which the gene expression had significant differences between diffuse- and intestinal-type GC in RNA sequencing of the publicly available data identified 1099 causal networks in diffuse- and intestinal-type GC. Master regulators of the causal networks included lenvatinib, pyrotinib, histone deacetylase 1 (HDAC1), mir-196, and erb-b2 receptor tyrosine kinase 2 (ERBB2). The analysis of the HDAC1-interacting network identified the involvement of EMT regulation via the growth factors pathway, the coronavirus pathogenesis pathway, and vorinostat. The network had RNA-RNA interactions with microRNAs such as mir-10, mir-15, mir-17, mir-19, mir-21, mir-223, mir-25, mir-27, mir-29, and mir-34. The molecular networks revealed in the study may lead to identifying drug targets for GC.

Gastric cancer cell-derived exosomal miR-541-5p induces M2 macrophage polarization through DUSP3/JAK2/STAT3 pathway

PurposeExosomal microRNAs have been identified as important mediators of communication between tumor cells and macrophages in the microenvironment. miR-541-5p was reported to be involved in hepatocellular carcinoma progression, but its role in gastric cancer (GC) and in GC cell-macrophage crosstalk is unknown.MethodsCell proliferation, migration and invasion were respectively assessed by CCK-8 assay, scratch and Transwell assays. RT-qPCR was used to detect the level of miR-541-5p, macrophage markers and DUSP3. The percentage of CD11b+CD206+ cell population was analyzed by flow cytometry. Western blotting was employed to evaluate DUSP3-JAK2/STAT3 pathway proteins and exosome markers. The interaction between miR-541-5p and DUSP3 was verified by luciferase assay.ResultsThe results showed that miR-541-5p was upregulated in GC tissues and cells, and stimulated GC cell growth, migration and invasion in vitro. GC cells induce M2 macrophage polarization by secreting the exosomal miR-541-5p. Exosomal miR-541-5p maintained JAK2/STAT3 pathway activation in macrophages by targeting negative regulation of DUSP3. Inhibiting miR-541-5p significantly limited tumor growth in vivo.ConclusionIn conclusion, miR-541-5p promotes GC cell progression. GC cells may induce macrophage M2 polarization through the exosomal miR-541-5p-mediated DUSP3/JAK2/STAT3 pathway. miR-541-5p may be a potential therapeutic target for GC.

Comprehensive landscape of gastric cancer-targeted therapy and identification of CSNK2A1 as a potential target

ObjectiveTo conduct a comprehensive analysis of the landscape of gastric cancer (GC)-targeted therapy clinical trials and identify potential therapeutic targets. MethodsA systematic search and analysis of the Cochrane Central Register of Controlled Trials (CENTRAL) was performed to retrieve all GC clinical trials published up to June 30, 2022. Approved therapeutic targets for 11 common cancers were compiled and analyzed. The role of CSNK2A1 in GC was investigated using bioinformatics tools such as GEPIA, KMPLOT, SangerBox, STRING, ACLBI, and TIMER. Four gastric cancer cell lines (AGS, HGC, MGC, BGC) and one normal gastric mucosa cell line (GES-1) were utilized to assess the sensitivity to the CSNK2A1 inhibitor CX-4945. Quantitative real-time polymerase chain reaction (qPCR) was employed to quantify the cellular expression of CSNK2A1. Cellular apoptosis was evaluated using flow cytometry and Western blot analysis. ResultsThe failure rate of GC randomized controlled clinical trials (RCTs) was strikingly high, accounting for 74.29 % (26/35) of the trials. Among the 35 approved targets in 11 different cancers, 13 targets were rigorously evaluated and identified as potential therapeutic targets for GC. Bioinformatics analysis revealed that CSNK2A1 is closely associated with multiple biological characteristics in GC, and its increased expression correlated significantly with enhanced sensitivity to CX-4945 treatment. Flow cytometry and Western blot analysis consistently demonstrated concentration-dependent apoptosis induced by CX-4945 in GC cell lines. ConclusionsThe high failure rate of GC clinical trials highlights the need for a more scientific and precise approach in target identification and clinical trial design. CSNK2A1 emerges as a promising therapeutic target for GC, and its expression level could potentially serve as a biomarker for predicting sensitivity to CX-4945 treatment. Further research is warranted to elucidate the underlying molecular mechanisms and validate the clinical significance of CSNK2A1 in GC therapy.

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.

Long Noncoding RNA CRNDE Promotes Gastric Cancer Progression through Targeting miR-136-5p/MIEN1.

Background: Long noncoding RNAs (lncRNAs) contribute to the initiation and progression of gastric cancer (GC). The purpose of this study is to examine the potential role of lncRNA colorectal neoplasia differentially expressed (CRNDE)in modulating the expression of migration and invasion enhancer 1 (MIEN1) through the suppression of miR-136-5p in GC. Methods: The biological roles of CRNDE, miR-136-5p, and MIEN1 in GC were assessed both in laboratory settings and through the examination of clinical samples. Results: CRNDEwas found to be significantly increased in GC tissues, and this upregulation was associated with an unfavorable prognosis of GC patients. In vitro experiments showed that inhibiting cell growth and migration, along with promoting apoptosis in GC cells, could be achieved by either disabling CRNDEor MIEN1, or by increasing the expression of miR-136-5p. MIEN1 is a specific recipient of miR-136-5p, and the anticancer effects of miR-136-5p can be counteracted by the increased expression of MIEN1. Through the examination of clinical specimens, it has been observed that there is a significant positive correlation between the expression of MIEN1 and CRNDE. In contrast, miR-136-5p expression in GC tissues shows a negative correlation. Conclusion: A previously unexplored therapeutic target for GC involves the CRNDE/miR-136-5p/MIEN1 signal transduction cascade.

System-wide identification of novel de-ubiquitination targets for USP10 in gastric cancer metastasis through multi-omics screening

ObjectiveUbiquitin-specific peptidase 10 (USP10), a typical de-ubiquitinase, has been found to play a double-edged role in human cancers. Previously, we reported that the expression of USP10 was negatively correlated with the depth of gastric wall invasion, lymph node metastasis, and prognosis in gastric cancer (GC) patients. However, it remains unclear whether USP10 can regulate the metastasis of GC cells through its de-ubiquitination function.MethodsIn this study, proteome, ubiquitinome, and transcriptome analyses were conducted to comprehensively identify novel de-ubiquitination targets for USP10 in GC cells. Subsequently, a series of validation experiments, including in vitro cell culture studies, in vivo metastatic tumor models, and clinical sample analyses, were performed to elucidate the regulatory mechanism of USP10 and its de-ubiquitination targets in GC metastasis.ResultsAfter overexpression of USP10 in GC cells, 146 proteins, 489 ubiquitin sites, and 61 mRNAs exhibited differential expression. By integrating the results of multi-omics, we ultimately screened 9 potential substrates of USP10, including TNFRSF10B, SLC2A3, CD44, CSTF2, RPS27, TPD52, GPS1, RNF185, and MED16. Among them, TNFRSF10B was further verified as a direct de-ubiquitination target for USP10 by Co-IP and protein stabilization assays. The dysregulation of USP10 or TNFRSF10B affected the migration and invasion of GC cells in vitro and in vivo models. Molecular mechanism studies showed that USP10 inhibited the epithelial-mesenchymal transition (EMT) process by increasing the stability of TNFRSF10B protein, thereby regulating the migration and invasion of GC cells. Finally, the retrospective clinical sample studies demonstrated that the downregulation of TNFRSF10B expression was associated with poor survival among 4 of 7 GC cohorts, and the expression of TNFRSF10B protein was significantly negatively correlated with the incidence of distant metastasis, diffuse type, and poorly cohesive carcinoma.ConclusionsOur study established a high-throughput strategy for screening de-ubiquitination targets for USP10 and further confirmed that inhibiting the ubiquitination of TNFRSF10B might be a promising therapeutic strategy for GC metastasis.

KIAA1429 promotes gastric cancer progression by destabilizing RASD1 mRNA in an m6A-YTHDF2-dependent manner

BackgroundKIAA1429, a regulatory subunit of the N6-methyladenosine (m6A) methyltransferase complex, has been implicated in the progression of various cancers. However, the role of KIAA1429 in gastric cancer (GC) and its underlying mechanisms remain elusive. This study aimed to investigate the role of KIAA1429 in GC and to elucidate the underlying mechanisms.MethodsThe expression patterns and clinical relevance of KIAA1429 in GC were assessed using quantitative real-time PCR (qRT-PCR), Western blotting, immunohistochemistry (IHC), and bioinformatic analysis. In vitro and in vivo loss- and gain-of-function assays, m6A dot blot assays, methylated RNA immunoprecipitation sequencing (MeRIP-seq), RNA-seq, MeRIP-qPCR, dual luciferase reporter assays, RNA stability assays, RNA immunoprecipitation (RIP) assays, and RNA pull-down assays were performed to investigate the biological functions and underlying molecular mechanisms of KIAA1429 in GC.ResultsBoth the mRNA and protein expression of KIAA1429 were greater in GC tissues than in normal gastric tissues. High KIAA1429 expression correlated positively with poor prognosis in GC patients. KIAA1429 not only promoted GC cell proliferation, colony formation, G2/M cell cycle transition, migration, and invasion in vitro but also enhanced GC tumor growth and metastasis in vivo. Mechanistically, KIAA1429 increased the m6A level of RASD1 mRNA and enhanced its stability in an m6A-YTHDF2-dependent manner, thereby upregulating its expression. RASD1 knockdown partially rescued the KIAA1429 knockdown-induced impairment of pro‑oncogenic ability in GC cells. The expression levels of KIAA1429 and RASD1 were negatively correlated in GC tissues.ConclusionsKIAA1429 plays a pro‑oncogenic role in GC by downregulating RASD1 expression through destabilizing RASD1 mRNA in an m6A-YTHDF2-dependent manner. KIAA1429 may serve as a prognostic biomarker and therapeutic target for GC.

Downregulation of HIGD1B induces mitochondria-mediated apoptosis in gastric cancer cells by inactivating Akt and ERK pathways.

Gastric cancer (GC) is one of the most common malignancies worldwide. Hypoxia-inducible domain (HIGD) family members (e.g., HIGD1A) have been linked to tumor progression. However, the role of HIGD1B (another HIGD family member) in GC has yet to be fully understood. Based on data from TCGA_GC, GSE65801, and GSE65801 data sets, HIGD1B levels were evaluated in normal and GC tissues. Next, HIGD1B levels were validated by reverse transcription-quantitative PCR and western blot analysis analyses. Meanwhile, patients with GC in the TCGA_GC cohort were grouped into high- and low-HIGD1B level groups, and overall survival, functional enrichment, and immune infiltration were analyzed. Additionally, gain- and loss-of-function experiments were performed to determine the function of HIGD1B in GC cells. Compared to normal controls, HIGD1B mRNA levels were significantly elevated in GC tissues. Moreover, high HIGD1B levels may be an independent indicator of poor prognosis in patients with GC. Additionally, high HIGD1B levels were correlated with high stromal and ESTIMATE scores and elevated expression of immune checkpoints in patients with GC. Functional analyses showed that HIGD1B deficiency notably suppressed GC cell proliferation, migration, and invasion. Moreover, HIGD1B deficiency significantly induced mitochondria-mediated apoptosis in GC cells by inactivating Akt and ERK pathways. Collectively, HIGD1B may predict the prognosis of patients with GC and may function as an oncogene in GC. These findings suggest that HIGD1B may serve as a prognostic biomarker and potential therapeutic target in GC.

PKP2 induced by YAP/TEAD4 promotes malignant progression of gastric cancer.

Gastric cancer (GC) exhibits significant heterogeneity and its prognosis remains dismal. Therefore, it is essential to investigate new approaches for diagnosing and treating GC. Desmosome proteins are crucial for the advancement and growth of cancer. Plakophilin-2 (PKP2), a member of the desmosome protein family, frequently exhibits aberrant expression and is strongly associated with many tumor types' progression. In this study, we found upregulation of PKP2 in GC. Further correlation analysis showed a notable association between increased PKP2 expression and both tumor stage and poor prognosis in individuals diagnosed with gastric adenocarcinoma. In addition, our research revealed that the Yes-associated protein1 (YAP1)/TEAD4 complex could stimulate the transcriptional expression of PKP2 in GC. Elevated PKP2 levels facilitate activation of the AKT/mammalian target of rapamycin signaling pathway, thereby promoting the malignant progression of GC. By constructing a mouse model, we ultimately validated the molecular mechanism and function of PKP2 in GC. Taken together, these discoveries suggest that PKP2, as a direct gene target of YAP/TEAD4 regulation, has the potential to be used as an indication of GC progression and prognosis. PKP2 is expected to be a promising therapeutic target for GC.

A novel protein FNDC3B-267aa encoded by circ0003692 inhibits gastric cancer metastasis via promoting proteasomal degradation of c-Myc.

Gastric cancer (GC) ranks fifth in global cancer incidence and third in mortality rate among all cancer types. Circular RNAs (circRNAs) have been extensively demonstrated to regulate multiple malignant biological behaviors in GC. Emerging evidence suggests that several circRNAs derived from FNDC3B play pivotal roles in cancer. However, the role of circFNDC3B in GC remains elusive. We initially screened circFNDC3B with translation potential via bioinformatics algorithm prediction. Subsequently, Sanger sequencing, qRT-PCR, RNase R, RNA-FISH and nuclear-cytoplasmic fractionation assays were explored to assess the identification and localization of circ0003692, a circRNA derived from FNDC3B. qRT-PCR and ISH were performed to quantify expression of circ0003692 in human GC tissues and adjacent normal tissues. The protein-encoding ability of circ0003692 was investigated through dual-luciferase reporter assay and LC/MS. The biological behavior of circ0003692 in GC was confirmed via in vivo and in vitro experiments. Additionally, Co-IP and rescue experiments were performed to elucidate the interaction between the encoded protein and c-Myc. We found that circ0003692 was significantly downregulated in GC tissues. Circ0003692 had the potential to encode a novel protein FNDC3B-267aa, which was downregulated in GC cells. We verified that FNDC3B-267aa, rather than circ0003692, inhibited GC migration in vitro and in vivo. Mechanistically, FNDC3B-267aa directly interacted with c-Myc and promoted proteasomal degradation of c-Myc, resulting in the downregulation of c-Myc-Snail/Slug axis. Our study revealed that the novel protein FNDC3B-267aa encoded by circ0003692 suppressed GC metastasis through binding to c-Myc and enhancing proteasome-mediated degradation of c-Myc. The study offers the potential applications of circ0003692 or FNDC3B-267aa as therapeutic targets for GC.

ECHDC2 inhibits the proliferation of gastric cancer cells by binding with NEDD4 to degrade MCCC2 and reduce aerobic glycolysis

BackgroundThe Enoyl-CoA hydratase/isomerase family plays a crucial role in the metabolism of tumors, being crucial for maintaining the energy balance and biosynthetic needs of cancer cells. However, the enzymes within this family that are pivotal in gastric cancer (GC) remain unclear.MethodsWe employed bioinformatics techniques to identify key Enoyl-CoA hydratase/isomerase in GC. The expression of ECHDC2 and its clinical significance were validated through tissue microarray analysis. The role of ECHDC2 in GC was further assessed using colony formation assays, CCK8 assay, EDU assay, Glucose and lactic acid assay, and subcutaneous tumor experiments in nude mice. The mechanism of action of ECHDC2 was validated through Western blotting, Co-immunoprecipitation, and immunofluorescence experiments.ResultsOur analysis of multiple datasets indicates that low expression of ECHDC2 in GC is significantly associated with poor prognosis. Overexpression of ECHDC2 notably inhibits aerobic glycolysis and proliferation of GC cells both in vivo and in vitro. Further experiments revealed that overexpression of ECHDC2 suppresses the P38 MAPK pathway by inhibiting the protein level of MCCC2, thereby restraining glycolysis and proliferation in GC cells. Ultimately, it was discovered that ECHDC2 promotes the ubiquitination and subsequent degradation of MCCC2 protein by binding with NEDD4.ConclusionsThese findings underscore the pivotal role of the ECHDC2 in regulating aerobic glycolysis and proliferation in GC cells, suggesting ECHDC2 as a potential therapeutic target in GC.

Clinical Developments and Challenges in Treating FGFR2-Driven Gastric Cancer.

Recent advances in the treatment of gastric cancer (GC) with chemotherapy, immunotherapy, anti-angiogenic therapy and targeted therapies have yielded some improvement in survival outcomes; however, metastatic GC remains a lethal malignancy and amongst the leading causes of cancer-related mortality worldwide. Importantly, the ongoing molecular characterisation of GCs continues to uncover potentially actionable molecular targets. Among these, aberrant FGFR2-driven signalling, predominantly arising from FGFR2 amplification, occurs in approximately 3-11% of GCs. However, whilst several inhibitors of FGFR have been clinically tested to-date, there are currently no approved FGFR-directed therapies for GC. In this review, we summarise the significance of FGFR2 as an actionable therapeutic target in GC, examine the recent pre-clinical and clinical data supporting the use of small-molecule inhibitors, antibody-based therapies, as well as novel approaches such as proteolysis-targeting chimeras (PROTACs) for targeting FGFR2 in these tumours, and discuss the ongoing challenges and opportunities associated with their clinical development.

ALKBH5-mediated m6A modification of circFOXP1 promotes gastric cancer progression by regulating SOX4 expression and sponging miR-338-3p

Circular RNAs (circRNAs) have recently been suggested as potential functional modulators of cellular physiology processes in gastric cancer (GC). In this study, we demonstrated that circFOXP1 was more highly expressed in GC tissues. High circFOXP1 expression was positively associated with tumor size, lymph node metastasis, TNM stage, and poor prognosis in patients with GC. Cox multivariate analysis revealed that higher circFOXP1 expression was an independent risk factor for disease-free survival (DFS) and overall survival (OS) in GC patients. Functional studies showed that increased circFOXP1 expression promoted cell proliferation, cell invasion, and cell cycle progression in GC in vitro. In vivo, the knockdown of circFOXP1 inhibited tumor growth. Mechanistically, we observed ALKBH5-mediated m6A modification of circFOXP1 and circFOXP1 promoted GC progression by regulating SOX4 expression and sponging miR-338-3p in GC cells. Thus, our findings highlight that circFOXP1 could serve as a novel diagnostic and prognostic biomarker and potential therapeutic target for GC.

TM-Score predicts immunotherapy efficacy and improves the performance of the machine learning prognostic model in gastric cancer

Immunotherapy is becoming increasingly important, but the overall response rate is relatively low in the treatment of gastric cancer (GC). The application of tumor mutational burden (TMB) in predicting immunotherapy efficacy in GC patients is limited and controversial, emphasizing the importance of optimizing TMB-based patient selection. By combining TMB and major histocompatibility complex (MHC) related hub genes, we established a novel TM-Score. This score showed superior performance for immunotherapeutic selection (AUC = 0.808) compared to TMB, MSI status, and EBV status. Additionally, it predicted the prognosis of GC patients. Subsequently, a machine learning model adjusted by the TM-Score further improved the accuracy of survival prediction (AUC > 0.8). Meanwhile, we found that GC patients with low TM-Score had a higher mutation frequency, higher expression of HLA genes and immune checkpoint genes, and higher infiltration of CD8+ T cells, CD4+ helper T cells, and M1 macrophages. This suggests that TM-Score is significantly associated with tumor immunogenicity and tumor immune environment. Notably, based on the RNA-seq and scRNA-seq, it was found that AKAP5, a key component gene of TM-Score, is involved in anti-tumor immunity by promoting the infiltration of CD4+ T cells, NK cells, and myeloid cells. Additionally, siAKAP5 significantly reduced MHC-II mRNA expression in the GC cell line. In addition, our immunohistochemistry assays confirmed a positive correlation between AKAP5 and human leukocyte antigen (HLA) expression. Furthermore, AKAP5 levels were higher in patients with longer survival and those who responded to immunotherapy in GC, indicating its potential value in predicting prognosis and immunotherapy outcomes. In conclusion, TM-Score, as an optimization of TMB, is a more precise biomarker for predicting the immunotherapy efficacy of the GC population. Additionally, AKAP5 shows promise as a therapeutic target for GC.

USP31 Activates the Wnt/β-catenin Signaling Pathway and Promotes Gastric Cancer Cell Proliferation, Invasion and Migration.

Gastric cancer (GC) has a poor prognosis because it is highly aggressive, yet there are currently few effective therapies available. Although protein ubiquitination has been shown to play a complex role in the development of gastric cancer, to date, no efficient ubiquitinating enzymes have been identified as treatment targets for GC. The TCGA database was used for bioinformatic investigation of ubiquitin-specific protease 31 (USP31) expression in GC, and experimental techniques, including Western blotting, qRT-PCR, and immunohistochemistry, were used to confirm the findings. We also analyzed the relationship between USP31 expression and clinical prognosis in patients with GC. We further investigated the effects of USP31 on the proliferation, invasion, migration, and glycolysis of GC cells in vitro and in vivo by using colony formation, CCK-8 assays, Transwell chamber assays, cell scratch assays, and cell-derived xenograft. Furthermore, we examined the molecular processes by which USP31 influences the biological development of GC. Patients with high USP31 expression have a poor prognosis because USP31 is abundantly expressed in GC. Therefore, USP31 reduces the level of ubiquitination of the Wnt/β-catenin pathway by binding to β-catenin, thereby activating glycolysis, which ultimately promotes GC proliferation and aggressive metastasis. USP31 inhibits ubiquitination of β-catenin by binding to it, stimulates the Wnt/β-- catenin pathway, activates glycolysis, and accelerates the biology of GCs, which are all demonstrated in this work.

Prediction of novel biomarkers for gastric intestinal metaplasia and gastric adenocarcinoma using bioinformatics analysis

Background & aimThe histologic and molecular changes from intestinal metaplasia (IM) to gastric cancer (GC) have not been fully characterized. The present study sought to identify potential alterations in signaling pathways in IM and GC to predict disease progression; these alterations can be considered therapeutic targets. Materials & methodsSeven gene expression profiles were selected from the GEO database. Discriminate differentially expressed genes (DEGs) were analyzed by EnrichR. The STRING database, Cytoscape, Gene Expression Profiling Interactive Analysis (GEPIA), cBioPortal, NetworkAnalyst, MirWalk database, OncomiR, and bipartite miRNA‒mRNA correlation network was used for downstream analyses of selected module genes. ResultsAnalyses revealed that extracellular matrix-receptor interactions (ITGB1, COL1A1, COL1A2, COL4A1, FN1, COL6A3, and THBS2) in GC and PPAR signaling pathway interactions (FABP1, APOC3, APOA1, HMGCS2, and PPARA and PCK1) in IM may play key roles in both the carcinogenesis and progression of underlying GC from intestinal metaplasia. IM enrichment indicated that this is closely related to digestion and absorption. The TF-hub gene regulatory network revealed that AR, TCF4, SALL4, and ESR1 were more important for hub gene expression. It was revealed that the development and prediction of GC may be affected by hsa-miR-29. It was found that PTGR1, C1orf115, CRYL1, ALDOB, and SULT1B1 were downregulated in GC and upregulated in IM. Therefore, they might have tumor suppressor activity in GC progression. ConclusionNew potential biomarkers and pathways involved in GC and IM were identified that are important for the transformation of GC from IM to adenocarcinoma and can be therapeutic targets for GC.

High expression of NOTCH2 in gastric adenocarcinoma: A novel early diagnostic target.

NOTCH2 is overexpressed in gastric cancer (GC), and its enhanced activity is significantly correlated with worse tumor characteristics. We aim to analyze the clinicopathologic correlation between NOTCH2 and the molecular typing of GC by immunohistochemistry and by transcriptional sequencing. In this immunohistochemical study, we detected NOTCH2, EBER, P53, HER2, MLH1, MSH2, PMS2, and MSH6 and evaluated the association of NOTCH2 with clinical and histopathological features in a large single-institutional series of gastric adenocarcinomas (n=488). The correlation was also investigated between immunohistochemical results and survival outcomes. High NOTCH2 expression (2+/3+) was found in 139/488 (27.5%) samples analyzed. NOTCH2 expression was correlated with early stage T1 (P<0.0001), GC in the fundus (P=0.0364), and positive P53 status (P=0.0019). We did not find an association between NOTCH2 and HER2, microsatellite instability, EBER, and overall survival. Through RNA sequencing, it was revealed that NOTCH2 plays an important biological function in the pathogenesis and development of GC. Our findings suggested that NOTCH2 may be a potential diagnostic target for GC due to the fact that its high expression is closely associated with the early stages of cancer.

GGT5 facilitates migration and invasion through the induction of epithelial–mesenchymal transformation in gastric cancer

BackgroundGamma-glutamyltransferase 5 (GGT5), one of the two members in the GGT family (GGT1 and GGT5), plays a crucial role in oxidative regulation, inflammation promotion, and drug metabolism. Particularly in the tumorigenesis of various cancers, its significance has been recognized. Nevertheless, GGT5’s role in gastric cancer (GC) remains ambiguous. This study delves into the function and prognostic significance of GGT5 in GC through a series of in vitro experiments.MethodsEmploying online bioinformatics analysis tools such as The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), Kaplan–Meier plotter, and cBioPortal, we explored GGT5 characteristics and functions in GC. This encompassed aberrant expression, prognostic value, genomic alterations and mutations, immune cell infiltration, and associated signaling pathways. Immunohistochemistry was conducted to assess GGT5 expression in GC and adjacent normal tissues. Subsequently, univariate and multivariate logistic regression analyses were applied to investigate the associations between GGT5 and clinical characteristics. CCK8, wound healing, and migration assays were utilized to evaluate the impact of GGT5 on cell viability and migration. Additionally, Gene Set Enrichment Analysis (GSEA) and Western blot analysis were performed to scrutinize the activity of the epithelial–mesenchymal transformation (EMT) signaling pathway under GGT5 regulation.ResultsGGT5 exhibits upregulation in gastric cancer, with its overexpression significantly linked to histological differentiation in GC patients (P < 0.05). Multivariate analysis indicates that elevated GGT5 expression is an independent risk factor associated with poorer overall survival in gastric cancer patients (P < 0.05). In vitro experiments reveal that downregulation of GGT5 hampers the proliferation and migration of GC cell lines. Finally, GSEA using TCGA data highlights a significant correlation between GGT5 expression and genes associated with EMT, a finding further confirmed by Western blot analysis.ConclusionsGGT5 emerges as a promising prognostic biomarker and potential therapeutic target for GC.

Prognostic significance of connective tissue growth factor expression in stromal cells in patients with diffuse‑type gastric cancer.

Connective tissue growth factor (CTGF) is a target gene of the Hippo signaling pathway. Its differential role in the histological types of gastric cancer (GC) remains unknown; therefore, the present study aimed to confirm the clinical significance of CTGF expression in cancer and stromal cells in patients with GC depending on the histological type. The present study enrolled 589 patients with GC. Immunohistochemistry was used to analyze CTGF expression in cancer and stromal cells. CTGF mRNA expression data and the corresponding clinical information of GC samples were collected from The Cancer Genome Atlas (TCGA) database. Subsequently, the associations between CTGF expression and several clinicopathological factors were investigated. In the present study, CTGF expression was mainly observed in the cytoplasm of cancer and stromal cells. CTGF expression in stromal cells was significantly associated with CTGF expression in cancer cells (P<0.001). CTGF positivity in stromal cells was also significantly associated with intestinal type, non-scirrhous type, tumor depth (T1-2), lymph node metastasis (negative), lymphatic invasion (negative) and tumor size (<5 cm). Low CTGF expression in stromal cells was independently associated with worse overall survival (OS). Furthermore, the OS of patients with low CTGF expression in stromal cells, especially in patients with diffuse-type GC, was significantly worse than patients with high CTGF expression (P=0.022). This trend was similar to that revealed by TCGA data analysis. In conclusion, low CTGF expression was associated with a significantly worse OS in patients with diffuse-type GC. These data indicated that CTGF, and its control by the Hippo pathway, may be considered potential treatment targets in diffuse-type GC.