Transition In Gastric Cancer Cells Research Articles

Neutrophil-centric analysis of gastric cancer: prognostic modeling and molecular insights.

Gastric cancer remains a significant global health concern with poor prognosis. This study investigates the role of neutrophils in gastric cancer progression and their potential as prognostic indicators. Using multi-omics approaches, including Weighted Gene Co-expression Network Analysis (WGCNA), machine learning, and single-cell analysis, we identified neutrophil-associated gene signatures and developed a robust prognostic model. Our findings reveal distinct gastric cancer subtypes based on neutrophil-associated genes, with one subtype showing increased neutrophil infiltration and poorer prognosis. Single-cell analysis uncovered neutrophil-associated alterations in cell composition, gene expression profiles, and intercellular communication within the tumor microenvironment. Additionally, we explored the relationship between neutrophil-associated genes, microbiota composition, and alternative splicing events in gastric cancer. Furthermore, we identified QKI as a key regulator of alternative splicing and demonstrated its role in promoting malignant phenotypes and enhancing TGF-beta signaling and epithelial-mesenchymal transition in gastric cancer cells by wet experiment. Lastly, the role of QKI in the association with drug resistance and the identification of specific agents for treating QKI-associated drug resistance were also explored. This comprehensive study provides novel insights into the complex interplay between neutrophils, the tumor microenvironment, microbiota, alternative splicing and gastric cancer progression, offering potential new targets for therapeutic intervention.

Poria cocos inhibits the invasion, migration, and epithelial–mesenchymal transition of gastric cancer cells by inducing ferroptosis in cells

ObjectiveGastric cancer (GC) is one of the most prevalent malignant tumors of the digestive system. The advanced metastasis of gastric cancer severely limits the conventional approaches for its treatment, while certain traditional Chinese medicinal compounds have been reported to possess promising abilities in inhibiting tumor metastasis. Such as Poria (PA), known as Fu Ling in Chinese, is a commonly used traditional Chinese medicinal herb derived from Poria cocos, a fungus belonging to the polyporaceae family.MethodsThe proliferation capacity of cells was measured using the MTT assay, while the invasion and migration abilities of cells after treatment with different concentrations of PA were evaluated through wound healing assay and Transwell assay. The differential expression of mRNA was analyzed using qPCR. The in vivo growth of tumors was assessed by subcutaneous tumor formation in mice.ResultsBoth in vivo and in vitro experiments have demonstrated that PA significantly inhibits the proliferation of GC. Moreover, in vitro experiments have revealed that PA not only suppresses the invasion and migration of GC cells but also reverses TNF-β-induced EMT. Further experiments have revealed that PA inhibits cell invasion, migration and EMT by inducing ferroptosis in GC cells.ConclusionIn brief, the present study shows that PA inhibits tumor metastasis by inducing ferroptosis in GC cells. Our findings suggest that PA may have therapeutic potential in GC.

Upregulation of MFAP5 Enhances COL1A1 Expression, Promoting Epithelial-Mesenchymal Transition in Gastric Cancer Cells.

Gastric cancer (GC) is one of the most common types of cancer. Earlier research has suggested an association of microfibril-associated protein 5 (MFAP5) and collagen type I alpha 1 (COL1A1) with the progression of various tumors. However, the specific roles and mechanisms of action of MFAP5 and COL1A1 in the context of GC are yet to be fully elucidated. Thus, the objective of this study is to investigate the functions of MFAP5 and COL1A1 in the epithelial-mesenchymal transition (EMT) of GC and to unravel the associated molecular mechanisms. We examined the MFAP5 expression level in GC through real-time polymerase chain reaction (RT-PCR), western blotting, and immunohistochemistry. Subsequently, shRNA interference was employed to knockdown the expression of MFAP5 or COL1A1 in GC cells. Cell viability assay, Transwell assay, RT-PCR, and western blotting were then used to explore the impact of MFAP5 and COL1A1 on GC progression and metastasis, along with GC cell proliferation, migration, and EMT. Increased MFAP5 levels were observed in both GC tissues and cells (p < 0.05), with decreased MFAP5 levels significantly impeding GC cell activity and GC progression and metastasis (p < 0.05). Additionally, the pronounced reduction in the COL1A1 expression level effectively alleviated the migration and EMT processes induced by MFAP5 overexpression in GC cells (p < 0.05). These results indicate that MFAP5 plays a role in initiating the process of EMT in GC cells through the upregulation of COL1A1 expression.

Retracted] Nicotinamide N‑methyltransferase promotes epithelial‑mesenchymal transition in gastric cancer cells by activating transforming growth factor‑β1 expression.

[This retracts the article DOI: 10.3892/ol.2018.7885.].

Nanoparticles for Augmenting Therapeutic Potential and Alleviating the Effect of Di(2-ethylhexyl) Phthalate on Gastric Cancer.

Changes in diet culture and modern lifestyle contributed to a higher incidence of gastrointestinal-related diseases, including gastritis, implicated in the pathogenesis of gastric cancer. This observation raised concerns regarding exposure to di(2-ethylhexyl) phthalate (DEHP), which is linked to adverse health effects, including reproductive and developmental problems, inflammatory response, and invasive adenocarcinoma. Research on the direct link between DEHP and gastric cancer is ongoing, and further studies are required to establish a conclusive association. In our study, extremely low concentrations of DEHP exerted significant effects on cell migration by promoting the epithelial-mesenchymal transition in gastric cancer cells. This effect was mediated by the modulation of the PI3K/AKT/mTOR and Smad2 signaling pathways. To address the DEHP challenges, our initial design of TPGS-conjugated fucoidan, delivered via pH-responsive nanoparticles, successfully demonstrated binding to the P-selectin protein. This achievement has not only enhanced the antigastric tumor efficacy but has also led to a significant reduction in the expression of malignant proteins associated with the condition. These findings underscore the promising clinical therapeutic potential of our approach.

MBD3 promotes epithelial-mesenchymal transition in gastric cancer cells by upregulating ACTG1 via the PI3K/AKT pathway

BackgroundGastric cancer (GC) is a common malignancy and a leading cause of cancer-related death with high morbidity and mortality. Methyl-CpG binding domain protein 3 (MBD3), a key epigenetic regulator, is abnormally expressed in several cancers, participating in progression and metastasis. However, the role of MBD3 in GC remains unknown.MethodsMBD3 expression was assessed via public databases and validated by western blotting and quantitative real-time polymerase chain reaction (qRT-PCR). The prognosis of MBD3 was analysed via bioinformatics based on the TCGA dataset. The migration, invasion and proliferation of GC cells were examined by transwell, wound healing, cell counting kit (CCK)-8, colony-formation and xenograft mouse models. Epithelial-mesenchymal transition (EMT) and phosphatidylinositide 3-kinases/ protein Kinase B (PI3K/AKT) pathway markers were evaluated by Western blotting. RNA sequencing was used to identify the target of MBD3.ResultsMBD3 expression was higher in GC tissues and cells than in normal tissues and cells. Additionally, high MBD3 levels were associated with poor prognosis in GC patients. Subsequently, we proved that MBD3 enhanced the migration, invasion and proliferation abilities of GC cells. Moreover, western blot results showed that MBD3 promoted EMT and activated the PI3K/AKT pathway. RNA sequencing analysis showed that MBD3 may increase actin γ1 (ACTG1) expression to promote migration and proliferation in GC cells.ConclusionMBD3 promoted migration, invasion, proliferation and EMT by upregulating ACTG1 via PI3K/AKT signaling activation in GC cells and may be a potential diagnostic and prognostic target.

Extracellular putrescine can augment the epithelial-mesenchymal transition of gastric cancer cells by promoting MAL2 expression by elevating H3K27ac in its promoter region.

Dysregulation of polyamine metabolism has been associated with the development of many cancers. However, little information has been reported about the associations between elevated extracellular putrescine and epithelial-mesenchymal transition (EMT) of gastric cancer (GC) cells. In this study, the influence of extracellular putrescine on the malignant behavior and EMT of the AGS and MKN-28 cells was investigated, followed by RNA sequencing profiling of transcriptomic alterations and CUT&Tag sequencing capturing H3K27ac variations across the global genome using extracellular putrescine. Our results demonstrated that the administration of extracellular putrescine significantly promoted the proliferation, migration, invasion, and expression of N-cadherin in GC cells. We also observed elevated H3K27ac in MKN-28 cells but not in AGS cells when extracellular putrescine was used. A combination of transcriptomic alterations and genome-wide variations of H3K27ac highlighted the upregulated MAL2 and H3K27ac in its promoter region. Knockdown and overexpression of MAL2 were found to inhibit and promote EMT, respectively, in AGS and MKN-28 cells. We demonstrated that extracellular putrescine could upregulate MAL2 expression by elevating H3K27ac in its promoter region, thus triggering augmented EMT in GC cells.

ATP11A Promotes Epithelial-mesenchymal Transition in Gastric Cancer Cells via the Hippo Pathway.

Background: ATP11A, a P-type ATPase, functions as flippases at the plasma membrane to maintain cellular function and vitality in several cancers. However, the role of ATP11A in gastric cancer remains unknown. This study aimed to identify ATP11A related to the biological behavior of gastric cancer, and elucidate the underlying mechanism. Methods: The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) databases were used to analyze the expression and prognosis of ATP11A. The biofunctions of ATP11A were explored through Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Set Enrichment Analysis (GSEA). The expression of ATP11A were validated by immunohistochemistry (IHC), qRT-PCR and Western blotting. Transwell, wound healing, CCK8 and colony-formation were to detected the migration, invasion and proliferation of gastric cancer cells. The epithelial-mesenchymal transition (EMT) and Hippo pathway markers were examined by Western blotting. Results: The expression of ATP11A was higher in gastric cancer tissues than in normal tissues, and high ATP11A levels were related to worse prognosis of gastric cancer patients. Additionally, we proved that ATP11A promoted the migration, invasion and proliferation in gastric cancer cells. Furthermore, ATP11A was found to promote EMT by devitalizing the Hippo pathway. Conclusion: ATP11A promoted migration, invasion, proliferation and EMT via Hippo signaling devitalization in gastric cancer cells.

CD204-positive M2-like tumor-associated macrophages increase migration of gastric cancer cells by upregulating miR-210 to reduce NTN4 expression

BackgroundTumor-associated macrophages (TAMs) are the predominant immune cells in the tumor microenvironment and portend poor prognosis. However, the molecular mechanisms underlying the tumor promotion of TAMs have not been fully elucidated.MethodsCoculture of gastric cancer cells with U937 cells was performed to investigate the impact of TAMs on cancer cell behavior. MicroRNA (miRNA) microarray and bioinformatics were applied to identify the involved miRNAs and the functional target genes. The regulation of the miRNA on its target gene was studied using anti-miRNA and miRNA mimic.ResultsCoculture with CD204+ M2-like TAMs increased proliferation, migration, and epithelial-mesenchymal transition of gastric cancer cells. MiR-210 was the most upregulated miRNA in cancer cells identified by miRNA microarray after coculture. In gastric cancer tissues, miR-210 expression was positively correlated with CD204+ M2-like TAM infiltration. Inactivation of miR-210 by antimir attenuated CD204+ M2-like TAMs-induced cancer cell migration. Using pharmacological inhibitors and neutralizing antibodies, CD204+ M2-like TAMs-secreted TNFα was found to upregulate miR-210 through NF-κB/HIF-1α signaling. Bioinformatics analysis showed netrin-4 (NTN4) as a potential target of miR-210 to suppress gastric cancer cell migration. We also found an inverse expression between miR-210 and NTN4 in cancer cells after coculture or in tumor xenografts. Anti-miR-210 increased NTN4 expression, while miR-210 mimics downregulated NTN4 in cancer cells. Reporter luciferase assays showed that MiR-210 mimics suppressed NTN4 3’ untranslated region-driven luciferase activity in cancer cells, but this effect was blocked after mutating miR-210 binding site.ConclusionsCD204+ M2-like TAMs can utilize the TNF-α/NF-κB/HIF-1α/miR-210/NTN4 pathway to facilitate gastric cancer progression.

KRT80 expression works as a biomarker and a target for differentiation in gastric cancer.

Keratin 80 (KRT80) is a filament protein that participates in cell differentiation and the integrity of the epithelial barrier. Here, KRT80 expression was higher in gastric cancer compared with normal mucosa at both mRNA and protein levels by bioinformatic analysis, qRT-PCR and Western blot (p<0.05), however, the methylation of KRT80 was lower than in normal mucosa (p<0.05). There was a negative relationship between promoter methylation and expression level of KRT80 gene in gastric cancer (p<0.05). KRT80 mRNA and protein expression was positively correlated with the differentiation of gastric cancer (p<0.05), while KRT80 methylation was negatively associated with gastric cancer differentiation and p53 mutation (p<0.05). The expression of KRT80 mRNA was positively linked to the short survival time of gastric cancers (p<0.05). The differential genes of KRT80 mRNA were involved in ligand-receptor interaction, estrogen signal pathway, peptidase, filament and cytoskeleton, keratinocyte differentiation, vitamin D receptor, muscle contraction, and B cell-mediated immunity (p<0.05). KRT80-related genes were classified into cell adhesion and junction, cadherin binding, skin and epidermis development, and so forth (p<0.05). KRT80 knockdown suppressed proliferation, anti-apoptosis, anti-pyroptosis, migration, invasion and epithelial-mesenchymal transition in gastric cancer cells (p<0.05). These findings indicated that up-regulated expression of KRT80 played a crucial part in gastric carcinogenesis, and might be considered as a biological marker for aggressive behaviors and poor prognosis. Its silencing might be used as an approach of target therapy for gastric cancer patients.

Mediator Complex Subunit 8:Expression in Gastric Cancer, Prognostic Significance,and Impact on Cell Cycle

Objective To investigate the expression and prognostic significance of mediator complex subunit 8 (MED8) in gastric cancer and its impact on the cell cycle.Methods The expression of MED8 in gastric cancer and adjacent tissues and its correlation with patients' prognosis were analyzed using public databases.A validation cohort of 104 patients who underwent radical resection for gastric cancer in the First Affiliated Hospital of Bengbu Medical College from June 2012 to July 2017 was included.The receiver operating characteristic curve was established to evaluate the predictive value of MED8 for postoperative 5-year survival.Bioinformatics tools were used to predict the biological roles of MED8 in gastric cancer.The effect of the MED8 level on the G1/S phase transition of gastric cancer cells (MGC-803) was analyzed via lentivirus transduction and flow cytometry.Western blotting was carried out to assess the impact of MED8 expression on the protein levels of cyclin-dependent kinase 4(Cdk4) and G1/S-specific cyclin-D1(CyclinD1) in MGC-803 cells.Results The high expression of MED8 in the gastric cancer tissue was associated with poor prognosis (P<0.001) and had prognostic significance (area under curve=0.733,P<0.001).Gene enrichment analysis suggested that MED8 may participate in the cell cycle process.Flow cytometry results revealed that the upregulation of MED8 expression promoted the transition of MGC-803 cells from the G1 phase to the S phase (P<0.001),while the downregulation of MED8 had the opposite effect (P<0.001).Western blotting showed increases in the protein levels of Cdk4 and CyclinD1 in MGC-803 cells with upregulated MED8 expression (all P<0.001),and decreases in the cells with downregulated MED8 expression (all P<0.001).Conclusion MED8 is highly expressed in gastric cancer and may affect its progression and prognosis by regulating the G1/S phase transition of gastric cancer cells.

STYXL1 promotes proliferation and epithelial mesenchymal transition of gastric cancer cells via activating the PI3K/AKT pathway

STYXL1 promotes proliferation and epithelial mesenchymal transition of gastric cancer cells via activating the PI3K/AKT pathway

MAPK4 silencing in gastric cancer drives liver metastasis by positive feedback between cancer cells and macrophages

Liver metastasis is a major cause of death in gastric cancer patients, but the underlying mechanisms are poorly understood. Through a combination of in vivo screening and transcriptome profiling followed by quantitative RT-PCR and tissue array analyses, we found that mitogen-activated protein kinase 4 (MAPK4) downregulation in gastric cancer tissues from patients is significantly associated with liver metastasis and poor prognosis. The knockdown of MAPK4 in gastric cancer cells promotes liver metastasis in orthotopic mouse models. MAPK4 depletion in gastric cancer cells induces the secretion of macrophage migration inhibitory factor (MIF) to polarize tumor-associated macrophages (TAMs) in orthotopic xenograft tumors. Moreover, TAMs activate epithelial–mesenchymal transition of gastric cancer cells to suppress MAPK4 expression, which further increases MIF secretion to polarize TAMs. Taken together, our results suggest a previously undescribed positive feedback loop between cancer cells and macrophages mediated by MAPK4 silencing that facilitates gastric cancer liver metastasis.

RASSF1A inhibits epithelial-mesenchymal transition of gastric cancer cells by downregulating P-JNK.

Gastric cancer (GC) is one of the most common gastrointestinal tumors. In this study, we assessed the biological role of Ras association domain family 1 isoform A (RASSF1A) in GC cells. Expressions of RASSF1A and the relationship of RASSF1A with epithelial-mesenchymal transformation (EMT)-related proteins were assessed in five cell lines using Western blot. GC cells with RASSF1A overexpression were used to study sensitivity to cisplatin, migration, invasion, and the expression of EMT-associated biomarkers. GC cells showed profound downregulation of RASSF1A expression compared with normal human gastric mucosal cells. High RASSF1A expression was associated with increased overall survival. Overexpression of RASSF1A regulates GC cells activity and the expression of EMT-associated biomarkers. RASSF1A regulates E-cadherin and Vimentin through P-JNK pathway. Our results revealed that RASSF1A can inhibit the proliferation, migration, and invasion of GC cells via E-cadherin. Our study provides insights for further research on GC.

Interleukin-34 promotes the proliferation and epithelial-mesenchymal transition of gastric cancer cells.

BACKGROUNDInterleukin (IL)-34 is a pro-inflammatory cytokine involved in tumor development. The role of IL-34 in the proliferation and epithelial-mesenchymal transition (EMT) of gastric cancer (GC) remains to be investigated.AIMTo investigate whether and how IL-34 affects the proliferation of GC cells and EMT.METHODSUsing immunohistochemical staining, the expression of IL-34 protein was detected in 60 paired GC and normal paracancerous tissues and the relationship between IL-34 and clinicopathological factors was analyzed. The expression of IL-34 mRNA and protein in normal gastric epithelial cell lines and GC was detected using quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting, respectively. Stable IL-34 knockdown and overexpression in AGS cell lines were established by lentiviral infection and validated by qRT-PCR and western blotting. The cholecystokinin-8 assay, clone formation assay, cell scratch assay, and transwell system were used to detect GC cell proliferation, clone formation, migration, and invasion capacity, respectively. The effects of IL-34 on the growth of GC transplant tumors were assessed using a subcutaneous transplant tumor assay in nude mice. The effects of IL-34 on the expression level of EMT-associated proteins in AGS cells were examined by western blotting.RESULTSExpression of IL-34 protein and mRNA was higher in GC cell lines than in GES-1 cells. Compared to matched normal paraneoplastic tissues, the expression of IL-34 protein was higher in 60 GC tissues, which was correlated with tumor size, T-stage, N-stage, tumor, node and metastasis stage, and degree of differentiation. Knockdown of IL-34 expression inhibited the proliferation, clone formation, migration, and invasion of AGS cells, while overexpression of IL-34 promoted cell proliferation, clone formation, migration, and invasion. Furthermore, the reduction of IL-34 promoted the expression of E-cadherin in AGS cells but inhibited the expression of vimentin and N-cadherin. Overexpression of IL-34 inhibited E-cadherin expression but promoted expression of vimentin and N-cadherin in AGS cells. Overexpression of IL-34 promoted the growth of subcutaneous transplanted tumors in nude mice.CONCLUSIONIL-34 expression is increased in GC tissues and cell lines compared to normal gastric tissues or cell lines. In GC cells, IL-34 promoted proliferation, clone formation, migration, and invasion by regulating EMT-related protein expression cells. Interference with IL-34 may represent a novel strategy for diagnosis and targeted therapy of GC.

Interfering HMGB3 release from cancer-associated fibroblasts by miR-200b represses chemoresistance and epithelial-mesenchymal transition of gastric cancer cells.

Cancer-associated fibroblasts (CAFs) are vital components of gastric cancer (GC) microenvironments, which impact the aggressive characteristics of GC cells. The objective of this study is to evaluate the influence of High Mobility Group Box (HMGB) on CAF-related GC. The tissues of 10 GC patients who underwent surgery the Sanya Central Hospital of Hainan Province from July 2018 to July 2019 were collected for the clinical study. Moreover, the GC cell lines, including MGC-803, AGS, and SGC-7901, were used in vitro experiment. We investigated the molecular mechanism of the miR-200b/HMGB3 axis in affecting the chemoresistance and epithelial-mesenchymal transition (EMT) of GC cells induced by CAFs. Cell transfection, Cell Counting Kit-8 (CCK-8), Transwell assay, western blot, enzyme-linked immunosorbent assay (ELISA), and other experiments were employed. We found that miR-200b was down-regulated, yet HMGB3 was up-regulated in CAF-related GC. The CAFs markedly promoted cisplatin (CDDP) resistance, proliferation, invasion, migration, and EMT of GC cells. Gain-assay of miR-200b demonstrated that miR-200b inhibited the HMGB3 release from CAFs. In-vivo experiments confirmed that the growth and EMT of GC cells co-cultured with CAF-miR-200b were significantly reduced. Furthermore, CAFs enhanced the activation of ERK, JNK, and the Wnt/β-catenin pathways, and those pathways, as well as the malignant behaviors of GC cells, were obviously attenuated by miR-200b or HMGB3 silencing. Collectively, HMGB3 derived from CAFs is negatively regulated by miR-200b and promotes the malignant behaviors of GC cells.

Wilms tumor 1 associated protein promotes epithelial mesenchymal transition of gastric cancer cells by accelerating TGF-β and enhances chemoradiotherapy resistance.

Wilms tumor 1 associated protein (WTAP) is a key RNA n6-methyladenosine (m6A) methylase, which predicts the occurrence of many diseases, such as liver fibrosis formation, coordinating cancer stem cell function, and promoting tumor development. Gastric cancer (GC) is one of the most common malignant tumors worldwide. However, the role of WTAP in GC development and drug resistance remains unclear. Biological methods and data analysis were used to investigate the expression of WTAP in gastric carcinoma tissue. The expression of transforming growth factor-beta (TGF-β) and epithelial mesenchymal transition (EMT) in GC cells were detected by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blot (WB) with WTAP overexpression cell lines and WTAP knockout cell lines. Gradient concentrations of cisplatin (DDP), gradient cyclophosphamide (CTX), or radiation X-rays were added to WTAP overexpression cell lines and WTAP knockdown cell lines to observe the change of cell viability after radiotherapy and chemotherapy treatment. The expression of WTAP in gastric carcinoma tissue significantly increased as determined by bioinformatics analysis, and a high expression of WTAP was closely associated with poor prognosis of gastric cancer patients. Overexpression of WTAP promoted migration and EMT of GC cells and promoted the expression of TGF-β and the stability of mRNA. WTAP knockdown inhibited migration of GC cells and decreased TGF-β expression and stability of mRNA. In addition, WTAP promoted multiple chemotherapy resistance and radiotherapy resistance in GC. WTAP is a potential predictive biomarker for GC. Our findings revealed a novel mechanism by which WTAP regulates chemoradiotherapy resistance, extending the understanding of the m6A machinery in TGF-β induced EMT and metastasis in GC.

CircTHBS1 drives gastric cancer progression by increasing INHBA mRNA expression and stability in a ceRNA- and RBP-dependent manner

Circular RNAs (circRNAs) play vital regulatory roles in the progression of multiple cancers. In our study, transcriptome analysis and self-organizing maps (SOM) were applied to screen backbone circRNAs in gastric cancer (GC). Upon validation of the expression patterns of screened circRNAs, gain- and loss-of-function assays were performed in vitro and in vivo. Underlying mechanisms were investigated using RNA pull-down, luciferase reporter assay and RNA immunoprecipitation. The expression of circTHBS1 was significantly increased in GC and associated with poor prognosis. CircTHBS1 facilitated the malignant behavior and epithelial-to-mesenchymal transition of GC cells. Mechanistically, circTHBS1 sponged miR-204-5p to promote the expression of Inhibin Subunit Beta A (INHBA). Moreover, circTHBS1 could enhance the HuR-mediated mRNA stability of INHBA, which subsequently activated the TGF-β pathway. Our research identified circTHBS1 as an oncogenic circRNA that enhances GC malignancy by elevating INHBA expression, providing new insight and a feasible target for the diagnosis and treatment of GC.

MT1G inhibits the growth and epithelial-mesenchymal transition of gastric cancer cells by regulating the PI3K/AKT signaling pathway.

Gastric carcinoma (GC) is a malignant tumor that has high mortality and morbidity worldwide. Although many efforts have been focused on the development and progression of GC, the underlying functional regulatory mechanism of GC needs more clarification. Metallothionein 1G (MT1G) is a member of the metallothionein family (MTs), and hypermethylation of MT1G occurred in a variety of cancers, including gastric cancer. However, the functional mechanism of MT1G in GC remains unclear. Here, we demonstrated that MT1G was down-regulated in GC tissues and cells. Overexpression of MT1G inhibited cell proliferation, foci formation and cell invasion, while knockdown of MT1G increased cell proliferation, foci formation and cell invasion. In addition, MT1G overexpression inhibited cell cycle progression and MT1G deficiency exerted opposite phenotype. p-AKT was negatively regulated by MT1G. In summary, our study reveals that MT1G exerts crucial role in regulating of cell proliferation and migration of gastric cancer, providing new insights for MT1G-related pathogenesis and a basis for developing new strategies for treatment of GC.

The EMT-induced lncRNA NR2F1-AS1 positively modulates NR2F1 expression and drives gastric cancer via miR-29a-3p/VAMP7 axis

Deregulated lncRNAs play critical roles in tumorigenesis and tumor progression. NR2F1-AS1 is an antisense lncRNA of NR2F1. However, the biological function of NR2F1-AS1 in gastric cancer (GC) remains largely unclear. In this study, we revealed that NR2F1-AS1 and NR2F1 were both positively correlated with the degree of malignancy and predicted poor prognosis in two independent GC cohorts. Besides, NR2F1-AS1 and NR2F1 can respond to Epithelial-to-mesenchymal transition (EMT) signaling in GC, since their expression was increased by TGF-beta treatment and decreased after stable overexpression of OVOL2 in GC cell lines. NR2F1-AS1 and NR2F1 were highly co-expressed in pan-tissues and pan-cancers. Depletion of NR2F1-AS1 compromised the expression level of NR2F1 in GC cells. Furthermore, NR2F1-AS1 knockdown inhibited the proliferation, migration, invasion and G1/S transition of GC cells. More importantly, transcriptome sequencing revealed a novel ceRNA network composed of NR2F1-AS1, miR-29a-3p, and VAMP7 in GC. The overexpression of VAMP7 predicted poor prognosis in GC. Rescue assay confirmed that NR2F1-AS1 promotes GC progression through miR-29a-3p/VAMP7 axis. Our finding highlights that the aberrant expression of NR2F1-AS1 is probably due to the abnormal EMT signaling in GC. LncRNA NR2F1-AS1 plays crucial roles in GC progression by modulating miR-29a-3p/VAMP7 axis, suggesting that NR2F1-AS1 may serve as a potential therapeutic target in GC.