1.Significance of high expression of C5orf46 in gastric cancer and potential intervention of tarditional Chinese medicine based on bioinformatics, molecular docking, and cell experiments.
Ying-Jia ZHOU ; Jia-Ming LIU ; Bin LIU ; Zi-Xia WANG ; Xin-Yu FAN ; Pei-Zhen HUANG ; Yu-Xin HUANG ; Jing-Ning SUN ; Qi-Qi CHEN ; Hong-Mei SHEN
China Journal of Chinese Materia Medica 2023;48(9):2368-2378
This study aims to investigate the expression, prognosis, and clinical significance of C5orf46 in gastric cancer and to study the interaction between the active components of C5orf46 and tarditional Chinese medicine. The ggplot2 package was utilized for differential expression analysis of C5orf46 in gastric cancer tissues and normal tissues. The survival package was used for survival analysis, univariate regression analysis, and multivariate regression analysis. Nomogram analysis was used to assess the connection between C5orf46 expression in gastric cancer and overall survival. The abundance of tumor-infiltrating lymphocytes was calculated by GSVA package. Coremine database, Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP) database, and PubChem database were used to search the potential components corresponding to C5orf46 gene and tarditional Chinese medicine. Molecular docking was performed to explore the binding affinity of potential components to C5orf46. Cell experiments were performed to explore the expression of C5orf46 gene in cells of the blank group, model group, and drug administration groups. As compared with normal tissues, C5orf46 expression was higher in gastric cancer tissues, which had more significant predictive effects in the early stages(T2, N0, and M0). The more advanced the tumor node metastasis(TNM) stage, the higher the C5orf46 expression and the lower the probability of survival of patients with gastric cancer. The expression of C5orf46 positively correlated with the helper T cells1 in gastric cancer and the macrophage infiltration level in gastric cancer, and negatively correlated with B cells, central memory T cells, helper T cells 17, and follicular helper T cells. Seven potential components of C5orf46 were obtained, and three active components were obtained after the screening, which matched five tarditional Chinese medicines, namely, Sojae Semen Nigrum, Jujubae Fructus, Trichosanthis Fructus, Silybi Fructus, and Bambusae Concretio Silicea. Molecular docking revealed that sialic acid and adeno-sine monophosphate(AMP) had a good binding ability to C5orf46. The results of real-time quantitative polymerase chain reaction(RT-qPCR) and Western blot showed that, as compared with the model group, the mRNA and protein expression levels of C5orf46 were significantly lower in the drug administration groups. The lowest expression level was found at the concentration of 40 μmol·L~(-1). The results of this study provide ideas for the clinical development of traditional Chinese medicine compounds for the treatment of gastric cancer as well as other cancers.
Humans
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Stomach Neoplasms/metabolism*
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Medicine, Chinese Traditional
;
Molecular Docking Simulation
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Prognosis
;
Computational Biology
2.Flavonoid-Rich Extract of Oldenlandia diffusa (Willd.) Roxb. Inhibits Gastric Cancer by Activation of Caspase-Dependent Mitochondrial Apoptosis.
Jia-Yin LING ; Qiu-Lan WANG ; Hao-Nan LIANG ; Qing-Bo LIU ; Dong-Hong YIN ; Li LIN
Chinese journal of integrative medicine 2023;29(3):213-223
OBJECTIVE:
To evaluate the apoptosis and cycle arrest effects of Oldenlandia diffusa flavonoids on human gastric cancer cells, determine the action mechanisms in association with the mitochondrial dependent signal transduction pathway that controls production of reactive oxygen species (ROS), and evaluate the pharmacodynamics of a mouse xenotransplantation model to provide a reference for the use of flavonoids in prevention and treatment of gastric cancer.
METHODS:
Flavonoids were extracted by an enzymatic-ultrasonic assisted method and purified with D-101 resin. Bioactive components were characterized by high-performance liquid chromatography. Cell lines MKN-45, AGS, and GES-1 were treated with different concentrations of flavonoids (64, 96, 128, 160 µg/mL). The effect of flavonoids on cell viability was evaluated by MTT method, and cell nuclear morphology was observed by Hoechst staining. The apoptosis rate and cell cycle phases were measured by flow cytometry, the production of ROS was detected by laser confocal microscope, the mitochondrial membrane potential (MMP) were observed by fluorescence microscope, and the expression of apoptotic proteins related to activation of mitochondrial pathway were measured by immunoblotting. MKN-45 cells were transplanted into BALB/c nude mice to establish a xenograft tumor model. Hematoxylin and eosin staining was used to reveal the subcutaneous tumor tissue. The tumor volume and tumor weight were measured, the expression levels of proliferation markers proliferating cell nuclear antigen (PCNA) and Ki-67 were detected by immunohistochemistry, and the expression levels of CA72-4 were measured by enzyme linked immunosorbent assay.
RESULTS:
Oldenlandia diffusa flavonoids inhibited proliferation of MKN-45 and AGS human gastric cancer cells, arrested the cell cycle in G1/S phase, induced accumulation of ROS in the process of apoptosis, and altered MMP. In addition, flavonoids increased Apaf-1, Cleaved-Caspase-3, and Bax, and decreased Cyclin A, Cdk2, Bcl-2, Pro-Caspase-9, and Mitochondrial Cytochrome C (P<0.05). The MKN-45 cell mouse xenotransplantation model further clarified the growth inhibitory effect of flavonoids towards tumors. The expression levels of PCNA and Ki-67 decreased in each flavonoid dose group, the expression level of CA72-4 decreased (P<0.05).
CONCLUSION
Flavonoids derived from Oldenlandia diffusa can inhibit proliferation and induce apoptosis of human gastric cancer cells by activating the mitochondrial controlled signal transduction pathway.
Humans
;
Animals
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Mice
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Oldenlandia/metabolism*
;
Proliferating Cell Nuclear Antigen
;
Stomach Neoplasms
;
Flavonoids/pharmacology*
;
Reactive Oxygen Species/metabolism*
;
Mice, Nude
;
Ki-67 Antigen
;
Cell Line, Tumor
;
Apoptosis
;
Plant Extracts/pharmacology*
;
Caspases
;
Cell Proliferation
3.Effect of long non-coding RNA 114227 on gastric cancer cell proliferation and migration.
Haining GAN ; Huiying XIANG ; Yue XI ; Min YAO ; Chen SHAO ; Shihe SHAO
Journal of Central South University(Medical Sciences) 2023;48(2):157-164
OBJECTIVES:
Gastric cancer is a common cancer of the digestive system. Long non-coding RNA (lncRNA) plays an important role in the formation and development of gastric cancer. This study aims to investigate the effect of long non-coding lncRNA 114227 on biologic behaviors in gastric cancer cells.
METHODS:
The experiment was divided into 4 groups: a negative control (NC) group, a lncRNA 114227 small interference (si-lncRNA 114227) group, an empty vector (Vector) group, and an overexpression vector (OE-lncRNA 114227) group. The expressions of lncRNA 114227 in gastric mucosa and gastric cancer tissues, gastric mucosal epithelial cells and different gastric cancer strains were determined by real-time reverse transcription PCR (real-time RT-PCR).The proliferation were detected by CCK-8 assay in gastric cancer cells. The epithelial-mesenchymal transformation (EMT) was utilized by Transwell assay, scratch healing assay, and Western blotting in gastric cancer cells. The effect of lncRNA 114227 on proliferation of gastric cancer cells was detected by tumor bearing experiment in nude mice in vivo.
RESULTS:
The expression level of lncRNA 114227 in the gastric cancer tissues was significantly lower than that in the gastric mucosa tissues, and in 4 kinds of gastric cancer strains was all significantly lower than that in gastric mucosal epithelial cells (all P<0.01). In vitro, the proliferation and migration abilities of gastric cells were significantly reduced after overexpressing lncRNA 114227, and cell proliferation and migration were enhanced after silencing lncRNA 114227 (all P<0.05). The results of in vivo subcutaneous tumorigenesis in nude mice showed that the tumorigenic volume of the tumor-bearing mice in the OE-lncRNA 114227 group was significantly smaller than that of the Vector group, and the tumorigenic quality was lower than that of the Vector group (P<0.05), indicating that lncRNA 114227 inhibited tumorigenesis.
CONCLUSIONS
The expression of lncRNA 114227 is downregulated in gastric cancer gastric cancer tissues and cell lines. LncRNA 114227 may inhibit the proliferation and migration of gastric cancer cells through EMT process.
Animals
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Mice
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RNA, Long Noncoding/metabolism*
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Stomach Neoplasms/pathology*
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Mice, Nude
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Cell Line, Tumor
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Cell Proliferation/genetics*
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Carcinogenesis/genetics*
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Cell Movement/genetics*
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Epithelial-Mesenchymal Transition/genetics*
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Gene Expression Regulation, Neoplastic
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Apoptosis/genetics*
4.AAZ2 induces mitochondrial-dependent apoptosis by targeting PDK1 in gastric cancer.
Yi LI ; Wenyan SHE ; Xiaoran XU ; Yixin LIU ; Xinyu WANG ; Sheng TIAN ; Shiyi LI ; Miao WANG ; Chaochao YU ; Pan LIU ; Tianhe HUANG ; Yongchang WEI
Journal of Zhejiang University. Science. B 2023;24(3):232-247
Drastic surges in intracellular reactive oxygen species (ROS) induce cell apoptosis, while most chemotherapy drugs lead to the accumulation of ROS. Here, we constructed an organic compound, arsenical N-(4-(1,3,2-dithiarsinan-2-yl)phenyl)acrylamide (AAZ2), which could prompt the ROS to trigger mitochondrial-dependent apoptosis in gastric cancer (GC). Mechanistically, by targeting pyruvate dehydrogenase kinase 1 (PDK1), AAZ2 caused metabolism alteration and the imbalance of redox homeostasis, followed by the inhibition of phosphoinositide-3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway and leading to the activation of B-cell lymphoma 2 (Bcl2)/Bcl2-associated X (Bax)/caspase-9 (Cas9)/Cas3 cascades. Importantly, our in vivo data demonstrated that AAZ2 could inhibit the growth of GC xenograft. Overall, our data suggested that AAZ2 could contribute to metabolic abnormalities, leading to mitochondrial-dependent apoptosis by targeting PDK1 in GC.
Humans
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Signal Transduction
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Stomach Neoplasms/drug therapy*
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Reactive Oxygen Species/metabolism*
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Proto-Oncogene Proteins c-akt/metabolism*
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Apoptosis
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Proto-Oncogene Proteins c-bcl-2
;
Cell Line, Tumor
5.H19 recruited N 6 -methyladenosine (m 6 A) reader YTHDF1 to promote SCARB1 translation and facilitate angiogenesis in gastric cancer.
Rumeng BAI ; Miaomiao SUN ; Yuanyuan CHEN ; Shuaishuai ZHUO ; Guoxin SONG ; Tianjun WANG ; Zhihong ZHANG
Chinese Medical Journal 2023;136(14):1719-1731
BACKGROUND:
Angiogenesis is described as a complex process in which new microvessels sprout from endothelial cells of existing vasculature. This study aimed to determine whether long non-coding RNA (lncRNA) H19 induced the angiogenesis of gastric cancer (GC) and its possible mechanism.
METHODS:
Gene expression level was determined by quantitative real-time polymerase chain reaction and western blotting. Cell counting kit-8, transwell, 5-Ethynyl-2'-deoxyuridine (EdU), colony formation assay, and human umbilical vein endothelial cells (HUVECs) angiogenesis assay as well as Matrigel plug assay were conducted to study the proliferation, migration, and angiogenesis of GC in vitro and in vivo . The binding protein of H19 was found by RNA pull-down and RNA Immunoprecipitation (RIP). High-throughput sequencing was performed and next Gene Ontology (GO) as well as Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis was conducted to analyze the genes that are under H19 regulation. Methylated RIP (me-RIP) assay was used to investigate the sites and abundance among target mRNA. The transcription factor acted as upstream of H19 was determined through chromatin immunoprecipitation (ChIP) and luciferase assay.
RESULTS:
In this study, we found that hypoxia-induced factor (HIF)-1α could bind to the promoter region of H19, leading to H19 overexpression. High expression of H19 was correlated with angiogenesis in GC, and H19 knocking down could inhibit cell proliferation, migration and angiogenesis. Mechanistically, the oncogenic role of H19 was achieved by binding with the N 6 -methyladenosine (m 6 A) reader YTH domain-containing family protein 1 (YTHDF1), which could recognize the m 6 A site on the 3'-untransated regions (3'-UTR) of scavenger receptor class B member 1 (SCARB1) mRNA, resulting in over-translation of SCARB1 and thus promoting the proliferation, migration, and angiogenesis of GC cells.
CONCLUSION
HIF-1α induced overexpression of H19 via binding with the promoter of H19, and H19 promoted GC cells proliferation, migration and angiogenesis through YTHDF1/SCARB1, which might be a beneficial target for antiangiogenic therapy for GC.
Humans
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Cell Line, Tumor
;
Cell Proliferation/genetics*
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Endothelial Cells/metabolism*
;
Gene Expression Regulation
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Gene Expression Regulation, Neoplastic/genetics*
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Hypoxia
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MicroRNAs/genetics*
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RNA
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RNA, Long Noncoding/metabolism*
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RNA-Binding Proteins/metabolism*
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Scavenger Receptors, Class B/metabolism*
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Stomach Neoplasms/genetics*
6.B7-H3 confers stemness characteristics to gastric cancer cells by promoting glutathione metabolism through AKT/pAKT/Nrf2 pathway.
Lu XIA ; Yuqi CHEN ; Juntao LI ; Jiayu WANG ; Kanger SHEN ; Anjing ZHAO ; Haiyan JIN ; Guangbo ZHANG ; Qinhua XI ; Suhua XIA ; Tongguo SHI ; Rui LI
Chinese Medical Journal 2023;136(16):1977-1989
BACKGROUND:
Cancer stem-like cells (CSCs) are a small subset of cells in tumors that exhibit self-renewal and differentiation properties. CSCs play a vital role in tumor formation, progression, relapse, and therapeutic resistance. B7-H3, an immunoregulatory protein, has many protumor functions. However, little is known about the mechanism underlying the role of B7-H3 in regulating gastric cancer (GC) stemness. Our study aimed to explore the impacts of B7-H3 on GC stemness and its underlying mechanism.
METHODS:
GC stemness influenced by B7-H3 was detected both in vitro and in vivo . The expression of stemness-related markers was examined by reverse transcription quantitative polymerase chain reaction, Western blotting, and flow cytometry. Sphere formation assay was used to detect the sphere-forming ability. The underlying regulatory mechanism of B7-H3 on the stemness of GC was investigated by mass spectrometry and subsequent validation experiments. The signaling pathway (Protein kinase B [Akt]/Nuclear factor erythroid 2-related factor 2 [Nrf2] pathway) of B7-H3 on the regulation of glutathione (GSH) metabolism was examined by Western blotting assay. Multi-color immunohistochemistry (mIHC) was used to detect the expression of B7-H3, cluster of differentiation 44 (CD44), and Nrf2 on human GC tissues. Student's t -test was used to compare the difference between two groups. Pearson correlation analysis was used to analyze the relationship between two molecules. The Kaplan-Meier method was used for survival analysis.
RESULTS:
B7-H3 knockdown suppressed the stemness of GC cells both in vitro and in vivo . Mass spectrometric analysis showed the downregulation of GSH metabolism in short hairpin B7-H3 GC cells, which was further confirmed by the experimental results. Meanwhile, stemness characteristics in B7-H3 overexpressing cells were suppressed after the inhibition of GSH metabolism. Furthermore, Western blotting suggested that B7-H3-induced activation of GSH metabolism occurred through the AKT/Nrf2 pathway, and inhibition of AKT signaling pathway could suppress not only GSH metabolism but also GC stemness. mIHC showed that B7-H3 was highly expressed in GC tissues and was positively correlated with the expression of CD44 and Nrf2. Importantly, GC patients with high expression of B7-H3, CD44, and Nrf2 had worse prognosis ( P = 0.02).
CONCLUSIONS
B7-H3 has a regulatory effect on GC stemness and the regulatory effect is achieved through the AKT/Nrf2/GSH pathway. Inhibiting B7-H3 expression may be a new therapeutic strategy against GC.
Humans
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Cell Line, Tumor
;
Neoplasm Recurrence, Local
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NF-E2-Related Factor 2/metabolism*
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Proto-Oncogene Proteins c-akt/metabolism*
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Signal Transduction
;
Stomach Neoplasms
7.Xiaotan Sanjie recipe, a compound Chinese herbal medicine, inhibits gastric cancer metastasis by regulating GnT-V-mediated E-cadherin glycosylation.
Nian HUANG ; Hai-Wei HE ; Yu-Yu HE ; Wei GU ; Ming-Juan XU ; Long LIU
Journal of Integrative Medicine 2023;21(6):561-574
OBJECTIVE:
Xiaotan Sanjie recipe (XTSJ), a Chinese herbal compound medicine, exerts a significant inhibitory effect on gastric cancer (GC) metastasis. This work investigated the mechanism underlying the XTSJ-mediated inhibition of GC metastasis.
METHODS:
The effect of XTSJ on GC metastasis and the associated mechanism were investigated in vitro, using GC cell lines, and in vivo, using a GC mouse model, by focusing on the expression of Glc-N-Ac-transferase V (GnT-V; encoded by MGAT5).
RESULTS:
The migration and invasion ability of GC cells decreased significantly after XTSJ administration, which confirmed the efficacy of XTSJ in treating GC in vitro. XTSJ increased the accumulation of E-cadherin at junctions between GC cells, which was reversed by MGAT5 overexpression. XTSJ administration and MGAT5 knockdown alleviated the structural abnormality of the cell-cell junctions, while MGAT5 overexpression had the opposite effect. MGAT5 knockdown and XTSJ treatment also significantly increased the accumulation of proteins associated with the E-cadherin-mediated adherens junction complex. Furthermore, the expression of MGAT5 was significantly lower in the lungs of BGC-823-MGAT5 + XTSJ mice than in those of BGC-823-MGAT5 + solvent mice, indicating that the ability of gastric tumors to metastasize to the lung was decreased in vivo following XTSJ treatment.
CONCLUSION
XTSJ prevented GC metastasis by inhibiting the GnT-V-mediated E-cadherin glycosylation and promoting the E-cadherin accumulation at cell-cell junctions. Please cite this article as: Huang N, He HW, He YY, Gu W, Xu MJ, Liu L. Xiaotan Sanjie recipe, a compound Chinese herbal medicine, inhibits gastric cancer metastasis by regulating GnT-V-mediated E-cadherin glycosylation. J Integr Med. 2023; 21(6): 561-574.
Male
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Mice
;
Animals
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Stomach Neoplasms/genetics*
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Drugs, Chinese Herbal/pharmacology*
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Glycosylation
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Cell Line, Tumor
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Cadherins/metabolism*
8.Forkhead Box M1 Regulates the Proliferation,Invasion,and Drug Resistance of Gastric Cancer Cells via circ_NOTCH1.
Ning GE ; Yuan-Yuan JIANG ; Zhong-Ping PAN ; Jie WAN
Acta Academiae Medicinae Sinicae 2023;45(5):713-720
Objective To investigate the impacts of forkhead box M1(FOXM1)on the proliferation,invasion,and drug resistance of gastric cancer cells by regulating the circular RNA circ_NOTCH1.Methods Western blotting and real-time quantitative PCR were performed to determine the expression of FOXM1 protein and circ_NOTCH1,respectively,in the gastric cancer tissue,para-carcinoma tissue,human normal gastric mucosa epithelial cell line GES-1 and gastric cancer cell lines MGC-803,HGC-27,and BGC-823.BGC-823 cells were classified into the following groups:control,short hairpin RNA FOXM1(sh-FOXM1)and negative control(sh-NC),small interfering RNA circ_NOTCH1(si-circ_NOTCH1)and negative control(si-NC),and sh-FOXM1+circ_NOTCH1 overexpression plasmid(sh-FOXM1+pcDNA-circ_NOTCH1)and sh-FOXM1+negative control(sh-FOXM1+pcDNA).CCK-8 assay and clone formation assay were employed to measure the cell proliferation,and Transwell assay to measure cell invasion.After treatment with 1.0 mg/L adriamycin for 48 h,the cell resistance in each group was analyzed.Western blotting was employed to determine the expression levels of FOXM1,proliferating cell nuclear antigen(PCNA),Bax,multi-drug resistance-associated protein 1(MRP1),and multi-drug resistance gene 1(MDR1).RNA pull-down and RNA immunoprecipitation were employed to examine the binding of circ_NOTCH1 to FOXM1 protein.Results Compared with those in the para-carcinoma tissue,the expression levels of FOXM1 protein and circ_NOTCH1 in the gastric cancer tissue were up-regulated(all P<0.001).Compared with GES-1 cells,MGC-803,HGC-27,and BGC-823 cells showed up-regulated expression levels of FOXM1 protein and circ_NOTCH1(all P<0.001).Compared with the control group and sh-NC group,the sh-FOXM1 group with down-regulated expression of FOXM1 protein and circ_NOTCH1 showed decreased optical density value,clone formation rate,cell invasion number,and cell viability,down-regulated expression of PCNA,MRP1,and MDR1,and up-regulated expression of Bax protein in BGC-823 cells(all P<0.001).Compared with the control group and the si-NC group,the si-circ_NOTCH1 group with down-regulated expression of circ_NOTCH1 showed decreased optical density value,clone formation rate,cell invasion number,and cell viability,down-regulated expression of PCNA,MRP1,and MDR1,and up-regulated expression of Bax protein in BGC-823 cells(all P<0.001).Compared with sh-FOXM1 group and sh-FOXM1+pcDNA group,the sh-FOXM1+pcDNA-circ_NOTCH1 group with up-regulated expression of circ_NOTCH1 showed increased optical density value,clone formation rate,cell invasion number,and cell viability,up-regulated expression of PCNA,MRP1,and MDR1,and down-regulated expression of Bax protein(all P<0.001).FOXM1 protein was able to interact with circ_NOTCH1.Conclusion Interference with FOXM1 may inhibit the proliferation,invasion,and drug resistance of gastric cancer cells by silencing circ_NOTCH1 expression.
Humans
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bcl-2-Associated X Protein/metabolism*
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Carcinoma
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Cell Line, Tumor
;
Cell Proliferation/genetics*
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Drug Resistance
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Forkhead Box Protein M1/metabolism*
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Gene Expression Regulation, Neoplastic
;
MicroRNAs/genetics*
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Proliferating Cell Nuclear Antigen/metabolism*
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Receptor, Notch1/metabolism*
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RNA, Small Interfering/genetics*
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Stomach Neoplasms/genetics*
9.Association of Serine/Threonine Phosphoprotein Phosphatase 4C Expression With Prognosis of Gastric Cancer.
Zhi-Jun GENG ; Ju HUANG ; Qing-Qing LI ; Zhi-Xuan ZHOU ; Jing LI ; Xiao-Feng ZHANG ; Lian WANG ; Yue-Yue WANG ; Xue SONG ; Lu-Gen ZUO
Acta Academiae Medicinae Sinicae 2023;45(5):721-729
Objective To investigate the expression level of serine/threonine phosphoprotein phosphatase 4C(PPP4C)in gastric cancer,and analyze its relationship with prognosis and the underlying regulatory mechanism.Methods The clinical data of 104 gastric cancer patients admitted to the First Affiliated Hospital of Bengbu Medical College between January 2012 and August 2016 were collected.Immunohistochemical staining was employed to determine the expression levels of PPP4C and Ki-67 in the gastric cancer tissue.The gastric cancer cell lines BGC823 and HGC27 were cultured and transfected with the vector for PPP4C knockdown,the vector for PPP4C overexpression,and the lentiviral vector(control),respectively.The effects of PPP4C on the cell cycle and proliferation were analyzed and the possible regulatory mechanisms were explored.Results PPP4C was highly expressed in gastric cancer(P<0.001),and its expression promoted malignant progression of the tumor(all P<0.01).Univariate and Cox multivariate analysis clarified that high expression of PPP4C was an independent risk factor affecting the 5-year survival rate of gastric cancer patients(P=0.003).Gene ontology and Kyoto encyclopedia of genes and genomes enrichment analysis suggested that PPP4C may be involved in the cell cycle.The correlation analysis showed that the expression of PPP4C was positively correlated with that of Ki-67 in gastric cancer(P<0.001).The up-regulation of PPP4C expression increased the proportion of tumor cells in the S phase,alleviated the G2/M phase arrest,and promoted the proliferation of gastric cancer cells and the expression of cyclin D1 and cyclin-dependent kinase 6(CDK6)(all P<0.05).The down-regulation of PPP4C decreased the proportion of gastric cancer cells in the S phase,promoted G2/M phase arrest,and inhibited cell proliferation and the expression of cyclin D1,CDK6,and p53(all P<0.05).p53 inhibitors promoted the proliferation of BGC823 and HGC27 cells in the PPP4C knockdown group(P<0.001,P<0.001),while p53 activators inhibited the proliferation of BGC823 and HGC27 cells in the PPP4C overexpression group(P<0.001,P=0.002).Conclusions PPP4C is highly expressed in gastric cancer and affects the prognosis of the patients.It may increase the proportion of gastric cancer cells in the S phase and alleviate the G2/M phase arrest by inhibiting p53 signaling,thereby promoting cell proliferation.
Humans
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Stomach Neoplasms/genetics*
;
Cyclin D1/metabolism*
;
Tumor Suppressor Protein p53
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Phosphoproteins/metabolism*
;
Ki-67 Antigen
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Cell Line, Tumor
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Prognosis
;
Cell Proliferation
;
Phosphoprotein Phosphatases/metabolism*
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Threonine
;
Serine
10.Mediator Complex Subunit 8:Expression in Gastric Cancer, Prognostic Significance,and Impact on Cell Cycle.
Qiu-Sheng WANG ; Zhen ZHANG ; Zi YANG ; Xiao-Feng ZHANG ; Si-Tang GE ; Lu-Gen ZUO
Acta Academiae Medicinae Sinicae 2023;45(6):886-896
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.
Humans
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Stomach Neoplasms
;
Prognosis
;
Cell Proliferation
;
Cell Cycle
;
Mediator Complex/metabolism*
;
Cell Line, Tumor

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