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1.
Sci Rep ; 14(1): 14185, 2024 06 20.
Article in English | MEDLINE | ID: mdl-38902391

ABSTRACT

Helicobacter pylori (H. pylori), together with its CagA, has been implicated in causing DNA damage, cell cycle arrest, apoptosis, and the development of gastric cancer. Although lncRNA H19 is abundantly expressed in gastric cancer and functions as a pro-oncogene, it remains unclear whether lncRNA H19 contributes to the oncogenic process of H. pylori CagA. This study investigates the role of H19 in the DNA damage response and malignancy induced by H. pylori. It was observed that cells infected with CagA+ H. pylori strain (GZ7/cagA) showed significantly higher H19 expression, resulting in increased γH2A.X and p-ATM expression and decreased p53 and Rad51 expression. Faster cell migration and invasion was also observed, which was reversed by H19 knockdown in H. pylori. YWHAZ was identified as an H19 target protein, and its expression was increased in H19 knockdown cells. GZ7/cagA infection responded to the increased YWHAZ expression induced by H19 knockdown. In addition, H19 knockdown stimulated cells to enter the G2-phase and attenuated the effect of GZ7/cagA infection on the cellular S-phase barrier. The results suggest that H. pylori CagA can upregulate H19 expression, participate in the DNA damage response and promote cell migration and invasion, and possibly affect cell cycle arrest via regulation of YWHAZ.


Subject(s)
Antigens, Bacterial , Bacterial Proteins , Cell Movement , DNA Damage , Helicobacter pylori , RNA, Long Noncoding , Stomach Neoplasms , Humans , Antigens, Bacterial/metabolism , Antigens, Bacterial/genetics , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Helicobacter pylori/genetics , Stomach Neoplasms/microbiology , Stomach Neoplasms/genetics , Stomach Neoplasms/pathology , Stomach Neoplasms/metabolism , Cell Movement/genetics , Cell Line, Tumor , Helicobacter Infections/microbiology , Helicobacter Infections/genetics , Helicobacter Infections/metabolism , Rad51 Recombinase/metabolism , Rad51 Recombinase/genetics , Tumor Suppressor Protein p53/metabolism , Tumor Suppressor Protein p53/genetics , Histones/metabolism
2.
Cancer Cell Int ; 23(1): 326, 2023 Dec 16.
Article in English | MEDLINE | ID: mdl-38104099

ABSTRACT

BACKGROUND: Fibroblasts, especially cancer-associated fibroblasts (CAFs), represent the predominant stromal cell population in the tumor microenvironment and have an important function in tumorigenesis by interacting with tumor cells. However, their interaction remains elusive in an inflammatory tumor microenvironment induced by Helicobacter pylori (H. pylori). METHODS: The expression of Serpin family E member 1 (Serpin E1) was measured in fibroblasts with or without H. pylori infection, and primary gastric cancer (GC) cells. Serpin E1 knockdown and overexpression fibroblasts were generated using Serpin E1 siRNA or lentivirus carrying Serpin E1. Co-culture models of fibroblasts and GC cells or human umbilical vein endothelial cells (HUVECs) were established with direct contact or the Transwell system. In vitro functional experiments and in vivo tumorigenesis assay were employed to study the malignant behaviors of GC cells interacting with fibroblasts. ELISA was used for quantifying the levels of Serpin E1 and VEGFA in the culture supernatant. The tube formation capacity of HUVECs was assessed using a tube formation assay. Recombinant human Serpin E1 (recSerpin E1), anti-Serpin E1 antibody, and a MAPK pathway inhibitor were utilized to treat HUVECs for elucidating the underlying molecular mechanisms. RESULTS: Serpin E1 was predominantly expressed in gastric CAFs. H. pylori infection significantly enhanced the expression and secretion of Serpin E1 by CAFs. Both fibroblast-derived Serpin E1 and recSerpin E1 enhanced the growth, invasion, and migration of GC cells, along with increased VEGFA expression and tube formation in HUVECs. Furthermore, the co-inoculation of GC cells and fibroblasts overexpressing Serpin E1 triggered the expression of Serpin E1 in cancer cells, which facilitated together xenograft tumor growth and peritoneal dissemination of GC cells in nude mice, with an increased expression of Ki67, Serpin E1, CD31 and/or VEGFA. These processes may be mediated by Serpin E1-induced migration and p38 MAPK/VEGFA-mediated angiogenesis of HUVECs. CONCLUSION: H. pylori infection induces Serpin E1 expression in fibroblasts, subsequently triggering its expression in GC cells through their interaction. Serpin E1 derived from these cells promotes the migration and p38 MAPK/VEGFA-mediated angiogenesis of HUVECs, thereby facilitating GC growth and peritoneal metastasis. Targeting Serpin E1 signaling is a potential therapy strategy for H. pylori-induced GC.

3.
Angew Chem Int Ed Engl ; 62(45): e202312734, 2023 Nov 06.
Article in English | MEDLINE | ID: mdl-37735738

ABSTRACT

Single-atom catalysts (SACs) have emerged as crucial players in catalysis research, prompting extensive investigation and application. The precise control of metal atom nucleation and growth has garnered significant attention. In this study, we present a straightforward approach for preparing SACs utilizing a photocatalytic radical control strategy. Notably, we demonstrate for the first time that radicals generated during the photochemical process effectively hinder the aggregation of individual atoms. By leveraging the cooperative anchoring of nitrogen atoms and crystal lattice oxygen on the support, we successfully stabilize the single atom. Our Pd1 /TiO2 catalysts exhibit remarkable catalytic activity and stability in the Suzuki-Miyaura cross-coupling reaction, which was 43 times higher than Pd/C. Furthermore, we successfully depose Pd atoms onto various substrates, including TiO2 , CeO2 , and WO3 . The photocatalytic radical control strategy can be extended to other single-atom catalysts, such as Ir, Pt, Rh, and Ru, underscoring its broad applicability.

4.
Oncol Lett ; 26(4): 427, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37720672

ABSTRACT

Silencing XB130 inhibits cell proliferation and epithelial-mesenchymal transition in non-small cell lung cancer (NSCLC), suggesting that downregulating XB130 expression may impede NSCLC progression. However, the molecular mechanism underlying the regulation of XB130 expression remains unclear. In the present study, the role of the 3'-untranslated region (3'-UTR) in the regulation of XB130 expression was investigated. Recombinant psiCHECK-2 vectors with wild-type, truncated, or mutant XB130 3'-UTR were constructed, and the effects of these insertions on reporter gene expression were examined using a dual-luciferase reporter assay and reverse transcription-quantitative PCR. Additionally, candidate proteins that regulated XB130 expression by binding to critical regions of the XB130 3'-UTR were screened for using an RNA pull-down assay, followed by mass spectrometry and western blotting. The results revealed that insertion of the entire XB130 3'-UTR (1,218 bp) enhanced reporter gene expression. Positive regulatory elements were primarily found in nucleotides 113-989 of the 3'-UTR, while negative regulatory elements were found in the 1-112 and 990-1,218 regions of the 3'-UTR. Deletion analyses identified nucleotides 113-230 and 503-660 of the 3'-UTR as two major fragments that likely promote XB130 expression by increasing mRNA stability and translation rate. Additionally, a U-rich element in the 970-1,053 region of the 3'-UTR was identified as a negative regulatory element that inhibited XB130 expression by suppressing translation. Furthermore, seven candidate proteins that potentially regulated XB130 expression by binding to the 113-230, 503-660, and 970-1,053 regions of the 3'-UTR were identified, shedding light on the regulatory mechanism of XB130 expression. Collectively, these results suggested that complex sequence integrations in the mRNA 3'-UTR variably affected XB130 expression in NSCLC cells.

5.
Oncol Lett ; 25(6): 215, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37153057

ABSTRACT

Heterogeneous nuclear ribonucleoprotein A/B (hnRNPAB) is an RNA binding protein that is closely associated with the biological function and metabolism of RNA, which is involved in the malignant transformation of various tumor cells. However, the role and mechanisms of hnRNPAB in non-small cell lung cancer (NSCLC) are still unclear. In the present study, the expression levels of hnRNPAB in NSCLC and normal tissues were analyzed using the human protein atlas database and UALCAN database. The clinical significance of hnRNPAB was assayed using the data of NSCLC cases from The Cancer Genome Atlas database. Subsequently, two stable NSCLC cell lines with hnRNPAB knockdown were constructed and the effects of hnRNPAB silencing on cell viability, migration, invasion and epithelial-mesenchymal transition (EMT) were identified. Genes associated with hnRNPAB expression in NSCLC were screened using the Linked Omics database and verified by quantitative real-time PCR (RT-qPCR). The database analysis indicated that hnRNPAB was mainly expressed in the nucleus of NSCLC cells. Compared with the normal tissues, hnRNPAB expression was overexpressed in NSCLC tissues and was closely associated with the overall survival, sex, tumor-node-metastases classification, and poor prognosis of patients with lung adenocarcinoma. Functionally, knockdown of hnRNPAB inhibited the proliferation, migration, invasion and EMT of NSCLC cells and arrested the cell cycle at G1 phase. Mechanistically, the bioinformatics analysis and RT-qPCR verification demonstrated that hnRNPAB knockdown led to a significant expression change of genes associated with tumorigenesis. In conclusion, the present study indicated that hnRNPAB played an important role in the malignant transformation of NSCLC, supporting the significance of hnRNPAB as a novel potential therapeutic target for the early diagnosis and prognosis of NSCLC.

6.
Oncol Lett ; 25(4): 143, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36909372

ABSTRACT

Helicobacter pylori (Hp) is a primary risk factor for gastric cancer. The fat mass and obesity-associated (FTO) gene is associated with the development and progression of various cancer types such as glioma, leukemia, breast cancer and colorectal cancer. The aim of the present study was to investigate the effect of Hp infection on the expression of FTO and its roles in gastric cancer. It was found that the expression levels of both FTO mRNA and protein were significantly increased in Hp-infected human gastric mucosal epithelial cells and Mongolian gerbil gastric tissues. The expression of FTO in gastric cancer tissues was higher than that in para-cancer tissues. Data from The Cancer Genome Atlas demonstrated that FTO expression in gastric cancer tissues was significantly higher than that in normal tissues. Patient survival rate was significantly decreased in patients with high expression levels of FTO. It was also demonstrated that FTO expression was associated with several pathological parameters, such as tumor stage, metastasis stage and the American Joint Committee on Cancer stage. The FTO gene was positively correlated with 16,601 genes in gastric cancer and negatively correlated with 3,623 genes. Gene Ontology enrichment analysis demonstrated that FTO was significantly enriched in the regulation of gene expression and oxidative RNA demethylase activity, and it was associated with components such as the RNA N6-methyladenosine methyltransferase complex and nuclear speckle. In addition, knockdown of the FTO gene inhibited the migration and invasion of Hp-infected cells. In conclusion, the data suggests that Hp infection leads to upregulation of the FTO gene, which may be related to patient survival rate, tumor staging and other pathological parameters of patients with gastric cancer. It also suggests that FTO promotes proliferation and migration of gastric cancer cells, which may be involved in the pathogenesis of Hp-induced gastric cancer.

7.
Entropy (Basel) ; 24(11)2022 Oct 24.
Article in English | MEDLINE | ID: mdl-36359607

ABSTRACT

In this paper, the design of low probability of intercept (LPI) radar waveforms considers not only the performance of passive interception systems (PISs), but also radar detection and resolution performance. Waveform design is an important considerations for the LPI ability of radar. Since information theory has a powerful performance-bound description ability from the perspective of information flow, LPI waveforms are designed in this paper within the constraints of the detection performance metrics of radar and PISs, both of which are measured by the Kullback-Leibler divergence, and the resolution performance metric, which is measured by joint entropy. The designed optimization model of LPI waveforms can be solved using the sequential quadratic programming (SQP) method. Simulation results verify that the designed LPI waveforms not only have satisfactory target-detecting and resolution performance, but also have a superior low interception performance against PISs.

8.
Sensors (Basel) ; 22(13)2022 Jun 22.
Article in English | MEDLINE | ID: mdl-35808210

ABSTRACT

Since the passive sensor has the property that it does not radiate signals, the use of passive sensors for target tracking is beneficial to improve the low probability of intercept (LPI) performance of the combat platform. However, for the high-maneuvering targets, its motion mode is unknown in advance, so the passive target tracking algorithm using a fixed motion model or interactive multi-model cannot match the actual motion mode of the maneuvering target. In order to solve the problem of low tracking accuracy caused by the unknown motion model of high-maneuvering targets, this paper firstly proposes a state transition matrix update-based extended Kalman filter (STMU-EKF) passive tracking algorithm. In this algorithm, the multi-feature fusion-based trajectory clustering is proposed to estimate the target state, and the state transition matrix is updated according to the estimated value of the motion model and the observation value of multi-station passive sensors. On this basis, considering that only using passive sensors for target tracking cannot often meet the requirements of high target tracking accuracy, this paper introduces active radar for indirect radiation and proposes a multi-sensor collaborative management model based on trajectory clustering. The model performs the optimal allocation of active radar and passive sensors by judging the accumulated errors of the eigenvalue of the error covariance matrix and makes the decision to update the state transition matrix according to the magnitude of the fluctuation parameter of the error difference between the prediction value and the observation value. The simulation results verify that the proposed multi-sensor collaborative target tracking algorithm can effectively improve the high-maneuvering target tracking accuracy to satisfy the radar's LPI performance.

9.
Chronobiol Int ; 39(10): 1340-1351, 2022 10.
Article in English | MEDLINE | ID: mdl-35903031

ABSTRACT

BMAL1 is a core circadian clock gene that is expressed rhythmically in a variety of tumor cells and is related to cancer cell proliferation and chemoradiotherapy sensitivity. Radiotherapy plays an important role in the treatment of nasopharyngeal carcinoma (NPC). However, the rhythmicity of BMAL1 in NPC, as well as its precise role in radiotherapy, remains unclear. We assessed changes in BMAL1 expression over 48 h in NPC cells and normal nasopharyngeal epithelial cells NP69 using real-time quantitative polymerase chain reaction (RT-PCR) and western blotting (WB). Then, we induced the overexpression and knocked-down the levels of BMAL1 in NPC cells, and subsequently used Cell Counting Kit-8 assays to assess the proliferation of NPC cells. Xenograft tumour growth was used to evaluate the effect of BMAL1 in vivo. Immunohistochemical staining was used to detect the expression of BMAL1 protein in transplanted tumors. Gene Set Enrichment Analysis (GSEA) was performed to explore the biological signaling pathway. Finally, RT-PCR and WB were used to detect the expressions of BMAL1, p53 and p21. The results showed that the mRNA expression levels of circadian clock gene BMAL1 fluctuated rhythmically with time, and the expression levels of BMAL1 also changed depending on the protein levels in NPC and NP69 cells. Overexpression of BMAL1 inhibited the proliferation of NPC cells, while knockdown BMAL1 had the opposite effects. In a xenograft model, we observed that the upregulation of BMAL1 inhibited tumor growth and enhanced the sensitivity of NPC cells to radiotherapy. Ultimately, the downregulation of BMAL1 promoted tumor growth and decreased radiosensitivity. GSEA analysis suggested that BMAL1 significantly affected the p53 pathway. Overexpression of BMAL1 promoted the expression of p53 and p21, while the knockdown of BMAL1 inhibited the expression of p53 and p21. We speculate that BMAL1 has the potential to be a prognostic biomarker and therapeutic target for NPC.


Subject(s)
Circadian Clocks , Nasopharyngeal Neoplasms , ARNTL Transcription Factors/genetics , ARNTL Transcription Factors/metabolism , Cell Line, Tumor , Cell Proliferation , Circadian Clocks/genetics , Circadian Rhythm , Gene Expression Regulation, Neoplastic , Humans , Nasopharyngeal Carcinoma/metabolism , Nasopharyngeal Carcinoma/radiotherapy , Nasopharyngeal Neoplasms/radiotherapy , Tumor Suppressor Protein p53/genetics
10.
Folia Microbiol (Praha) ; 67(6): 923-934, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35829852

ABSTRACT

Helicobacter pylori (H. pylori) is a Gram-negative pathogen as a carcinogen of the class Ι, with unique genetic diversity and wide geographic differences. The high incidence of gastric cancer in East Asia may be related to the bacterial genotype. It is of great significance that the genome of H. pylori in East Asia is widely collected. Therefore, we combined two sequencing technologies (PacBio and Illumina HiSeq 4000) and multiple databases to sequence and annotate the whole genome of H. pylori GZ7 isolated from a gastric cancer patient in Guizhou, China. Furthermore, this sequence was further compared with the genome sequence of 23 H. pylori strains isolated from different regions through collinearity comparison, specific gene analysis, phylogenetic tree construction, etc. The results showed that the genome of H. pylori GZ7 consists of 1,579,995 bp circle chromosomes with a GC content of 39.51%. This chromosome has 1,572 coding sequences, three antibiotic resistance genes, five prophages, and 198 virulence genes. The comparative genome analyses showed that H. pylori GZ7 has 53 specific genes compared to the other 23 strains. Most of these specific genes have not been annotated and characterized until now, whose research may provide insights into the biological activities of this strain. H. pylori GZ7 has the closest genetic relationship with H. pylori F30, and the farthest genetic relationship with H. pylori ELS37, which indicates that H. pylori genomes have geographical differences. This information may provide a molecular basis and guidance for constructing diagnostic methods for H. pylori and researching subsequent experiments.


Subject(s)
Helicobacter Infections , Helicobacter pylori , Stomach Neoplasms , Humans , Helicobacter Infections/microbiology , Phylogeny , Stomach Neoplasms/genetics , Stomach Neoplasms/microbiology , Genome, Bacterial
11.
J Transl Med ; 20(1): 322, 2022 07 21.
Article in English | MEDLINE | ID: mdl-35864535

ABSTRACT

BACKGROUND: Helicobacter pylori (H. pylori) can disrupt the tight junctions between gastric epithelial cells and penetrate the intercellular spaces acting on epithelial cells, normal fibroblasts (NFs), and cancer-associated fibroblasts (CAFs), but their interaction in gastric cancer tumorigenesis and progression remains unclear. METHODS: Primary CAFs and NFs were isolated from paired gastric cancer tissues and adjacent normal tissues and identified by immunofluorescence staining and western blot analysis for FSP-1, α-SMA, FAP, and vimentin expression. RNA-sequencing was used to compare the transcriptomes between CAFs and NFs. The expressions of FAP, lumican, and α-SMA, human cytokine array, and Transwell assay were used to assess the transformation of NFs to CAFs. CCK-8 assay, colony formation, flow cytometry, Transwell assay, and nude mouse xenograft model were used to determine the effects of Serpin E1 on cell proliferation and metastasis in vitro and in vivo. Finally, Serpin E1 and/or FAP expression was measured in H. pylori-infected gerbil gastric mucosa and human gastric cancer tissues. RESULTS: Gastric CAFs are inflammatory CAFs with α-SMAlowFAPhighlumicanhigh. The interplay of H. pylori, fibroblasts, and cancer cells promotes the transition of NFs to CAFs by inducing cytokine release, especially Serpin E1. Long-term H. pylori infection and CAFs induce Serpin E1 expression in gerbil gastric tissues and human gastric cancer cells. Serpin E1 overexpression enhances the growth, migration, invasion of gastric cancer cells in vitro, and xenograft tumor growth in nude mice via inducing angiogenesis. Serpin E1 and FAP were highly expressed in cancer cells and CAFs of gastric cancer tissues, respectively, and a good correlation was observed between their expression. Higher Serpin E1 expression is negatively associated with the overall survival of patients with gastric cancer. CONCLUSIONS: The interplay of H. pylori, fibroblasts, and cancer cells induced Serpin E1 expression to promote the activation of NFs to CAFs and gastric carcinogenesis. Targeting Serpin E1 will provide a promising therapeutic strategy for gastric cancer by disrupting the interaction between H. pylori, CAFs, and gastric cancer cells.


Subject(s)
Helicobacter pylori , Stomach Neoplasms , Animals , Cell Line, Tumor , Cell Movement , Cell Proliferation , Cell Transformation, Neoplastic , Cytokines/metabolism , Fibroblasts/metabolism , Humans , Lumican/metabolism , Mice , Mice, Nude , Plasminogen Activator Inhibitor 1/metabolism , Stomach Neoplasms/pathology
12.
J Cancer ; 13(1): 134-145, 2022.
Article in English | MEDLINE | ID: mdl-34976177

ABSTRACT

Accumulated evidence suggests that a functional loop composed of gastrin and cholecystokinin B receptor (CCK-BR) may exist in gastric carcinogenesis. However, this suggestion is not completely supported due to a lack of direct evidence, and the underlying mechanism is not completely understood. Here, we evaluated the effects of gastrin/CCK-BR signaling on the cell growth, invasion, and expression of MMP-2 and VEGF, as well as xenograft growth in vivo. Furthermore, we detected gastrin mRNA content in human gastric cancer tissues, metastatic lymph nodes, and adjacent nontumor tissues. We found that the forced gastrin could promote the proliferation, migration, and invasion of gastric cancer cells by upregulating the expression of MMP-2 and VEGF. Blocking gastrin/CCK-BR signal using either Proglumide, a CCK-BR antagonist, or shRNA against GASTRIN significantly inhibited the gastrin-promoting effects. In vivo study revealed that the tumor growth in nude mice inoculated with gastrin-overexpressed cells was significantly faster than control cells. The gastrin mRNA content in metastatic lymph nodes was higher in patients with gastric cancer than in primary gastric cancer and adjacent nontumor tissues. In conclusion, we provided direct evidence and possible mechanism of gastrin/CCK-BR signaling in the initiation and progression of gastric cancer.

13.
Inflamm Res ; 71(1): 141-155, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34854954

ABSTRACT

OBJECTIVE: The CagA (cytotoxin-related gene A, CagA) protein is an important factor for the pathogenicity of Helicobacter pylori (H. pylori). Although H. pylori has previously been shown to activate the NLRP3 inflammasome, it remains unclear what role CagA plays in this process. In the current study, we aimed to investigate the effect of CagA on NLRP3 activation and how it is linked to gastric cancer cell migration and invasion. METHODS: CagA positive H. pylori strain (Hp/CagA+) and CagA gene knockout mutant (Hp/ΔCagA) infected and the pcDNA3.1/CagA plasmid transfected gastric epithelial cell lines, respectively. The morphological alterations of cells under a microscope; the NLRP3 inflammasome-related markers: NLRP3, caspase-1, and ASC protein levels were detected by Western blot, IL-1ß and IL-18 levels were determined by ELISA; cell migration and invasion were determined by transwell assay; and the pyroptosis levels and intracellular ROS were determined by flow cytometry analysis. Then, pretreated with 5 mM NAC for 2 h and subsequently transfected with the pcDNA3.1/CagA plasmid for 48 h, the effects of NAC pretreatment on CagA-induced NLRP3 inflammasome-related markers expression and cell pyroptosis were examined, finally assessed the effect of CagA on migration and invasion in NLRP3-silenced cells. RESULTS: We found that Hp/CagA+ strain infection and pcDNA3.1/CagA vector transfection result in NLRP3 inflammasome activation, generation of intracellular ROS, and increased invasion and migration of gastric cancer cells. Moreover, we found that ROS inhibition via NAC effectively blocks NLRP3 activation and pyroptosis. Silencing of NLRP3 reduces the effects of CagA on gastric cancer cell migration and invasion. CONCLUSION: Our study shows that CagA can promote the invasion and migration of gastric cancer cells by activating NLRP3 inflammasome pathway. These findings provide novel insights into the mechanism of gastric cancer induction by H. pylori.


Subject(s)
Helicobacter Infections , Helicobacter pylori , Stomach Neoplasms , Antigens, Bacterial/genetics , Antigens, Bacterial/metabolism , Bacterial Proteins/genetics , Cell Movement , Helicobacter Infections/complications , Helicobacter Infections/genetics , Helicobacter Infections/metabolism , Helicobacter pylori/genetics , Helicobacter pylori/metabolism , Humans , Inflammasomes/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism
14.
World J Gastroenterol ; 28(47): 6769-6787, 2022 Dec 21.
Article in English | MEDLINE | ID: mdl-36620343

ABSTRACT

BACKGROUND: Gastric cancer (GC) is a common malignant tumor with high incidence and mortality rates globally, especially in East Asian countries. Helicobacter pylori (H. pylori) infection is a significant and independent risk factor for GC. However, its underlying mechanism of action is not fully understood. Dickkopf-related protein (DKK) 1 is a Wnt signaling antagonist, and cytoskeleton-associated protein (CKAP) 4 is a newly identified DKK1 receptor. Recent studies found that the binding of DKK1 to CAKP4 mediated the procancer signaling of DKK1 inde-pendent of Wnt signaling. We hypothesize that H. pylori-induced activation of DKK1/CKAP4 signaling contributes to the initiation and progression of GC. AIM: To investigate the interaction of H. pylori infection, DKK1 and CAKP4 in GC, as well as the underlying molecular mechanisms. METHODS: RNA sequencing was used to identify differentially expressed genes (DEGs) between H. pylori-infected and uninfected primary GC cells. Gain- and loss-of-function experiments were performed to verify the H. pylori-induced upregulation of activator protein-1 (AP-1) in GC cells. A dual-luciferase reporter assay and co-immunoprecipitation were used to determine the binding of AP-1 to the DKK1 promoter and DKK1 to CKAP4. Western blotting and immunohistochemistry detected the expression of DKK1, CKAP4, and phos-phatidylinositol 3-kinase (PI3K) pathway-related proteins in GC cells and tissues. Functional experiments and tumorigenicity in nude mice detected malignant behavior of GC cells in vitro and in vivo. RESULTS: We identified 32 DEGs between primary GC cells with and without H. pylori infection, including JUN, fos-like antigen-1 (FOSL1), and DKK1, and confirmed that the three proteins and CKAP4 were highly expressed in H. pylori-infected GC cells, H. pylori-infected gerbil gastric tissues, and human GC tissues. JUN and FOSL1 form AP-1 to transcriptionally activate DKK1 expression by binding to the DKK1 promoter. Activated DKK1 bound to CKAP4, but not the most common Wnt coreceptor low-density lipoprotein receptor-related protein 5/6, to promote GC cell growth, colony formation, migration, invasion, and xenograft tumor growth in nude mice. All these effects were driven by activation of the PI3K/AKT/mammalian target of rapamycin (mTOR) pathway. Targeting the PI3K signaling pathway by LY294002 inhibited DKK1-mediated CKAP4/PI3K signaling activity and the malignant behavior of GC cells. CONCLUSION: H. pylori induces JUN and FOSL1 expression to form AP-1, which transcriptionally activates DKK1. Binding of DKK1 to KAKP4 contributes to gastric tumorigenesis via the PI3K/AKT/mTOR pathway.


Subject(s)
Helicobacter Infections , Intercellular Signaling Peptides and Proteins , Stomach Neoplasms , Animals , Humans , Mice , Cell Line, Tumor , Cell Transformation, Neoplastic , Cytoskeleton/metabolism , Cytoskeleton/pathology , Helicobacter Infections/pathology , Helicobacter pylori/physiology , Mice, Nude , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Stomach Neoplasms/pathology , TOR Serine-Threonine Kinases/metabolism , Transcription Factor AP-1/metabolism , Wnt Signaling Pathway , Intercellular Signaling Peptides and Proteins/metabolism
15.
Biochim Biophys Acta Mol Basis Dis ; 1868(1): 166268, 2022 01 01.
Article in English | MEDLINE | ID: mdl-34536536

ABSTRACT

OBJECTIVE: Treatment of acute myeloid leukemia (AML) remains a challenge. It is urgent to understand the microenvironment to improve therapy and prognosis. METHODS: Bioinformatics methods were used to analyze transcription expression profile of AML patient samples with complete clinical information from UCSC Xena TCGA-AML datasets and validate with GEO datasets. Western blot, qPCR, RNAi and CCK8 assay were used to assay the effect of GPX1 expression on AML cell viability and the expression of genes of interest. RESULTS: Our analyses revealed that highly expressed GPX1 in AML patients links to unfavorable prognosis. GPX1 expression was positively associated with not only fraction levels of myeloid-derived suppressor cells (MDSCs), monocytes and T cell exhaustion, the expression levels of MDSC markers, MDSC-promoting CCR2 and immune inhibitory checkpoints (TIM3/Gal-9, SIRPα and VISTA), but also negatively with low fraction levels of CD4+ and CD8+ T cells. Silencing GPX1 expression reduced AML cell viability and CCR2 expression. Moreover, GPX1-targetd kinases were PKC family, SRC family, SYK and PAK1, which promote AML progression and the resistance to therapy. Furthermore, Additionally, GPX1-associated prognostic signature (GPS) is an independent risk factor with high area under curve (AUC) values of receiver operating characteristic (ROC) curves. High risk group based on GPS enriched not only with endocytosis which transfers mitochondria to favor AML cell survival in response to chemotherapy, but also NOTCH, WNT and TLR signaling which promote therapy resistance. CONCLUSION: Our results revealed the significant involvement of GPX1 in AML immunosuppression via and provided a prognostic signature for AML patients.


Subject(s)
Glutathione Peroxidase/genetics , Immunosuppression Therapy , Leukemia, Myeloid, Acute/genetics , Receptors, CCR2/genetics , Aged , Antigens, Differentiation/genetics , B7 Antigens/genetics , Female , Gene Expression Regulation, Leukemic/genetics , Hepatitis A Virus Cellular Receptor 2 , Humans , Immune Tolerance/genetics , Leukemia, Myeloid, Acute/immunology , Leukemia, Myeloid, Acute/pathology , Male , Middle Aged , Myeloid-Derived Suppressor Cells/immunology , Myeloid-Derived Suppressor Cells/pathology , Prognosis , Receptors, Immunologic/genetics , Receptors, Notch/genetics , Risk Factors , Syk Kinase/genetics , Tumor Microenvironment/immunology , Wnt Signaling Pathway/genetics , p21-Activated Kinases/genetics , Glutathione Peroxidase GPX1
16.
PeerJ ; 9: e11203, 2021.
Article in English | MEDLINE | ID: mdl-33954041

ABSTRACT

AIM: Helicobacter pylori cytotoxin-associated protein A (CagA) is an important virulence factor known to induce gastric cancer development. However, the cause and the underlying molecular events of CagA induction remain unclear. Here, we applied integrated bioinformatics to identify the key genes involved in the process of CagA-induced gastric epithelial cell inflammation and can ceration to comprehend the potential molecular mechanisms involved. MATERIALS AND METHODS: AGS cells were transected with pcDNA3.1 and pcDNA3.1::CagA for 24 h. The transfected cells were subjected to transcriptome sequencing to obtain the expressed genes. Differentially expressed genes (DEG) with adjusted P value < 0.05, - logFC -> 2 were screened, and the R package was applied for gene ontology (GO) enrichment and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. The differential gene protein-protein interaction (PPI) network was constructed using the STRING Cytoscape application, which conducted visual analysis to create the key function networks and identify the key genes. Next, the Kaplan-Meier plotter survival analysis tool was employed to analyze the survival of the key genes derived from the PPI network. Further analysis of the key gene expressions in gastric cancer and normal tissues were performed based on The Cancer Genome Atlas (TCGA) database and RT-qPCR verification. RESULTS: After transfection of AGS cells, the cell morphology changes in a hummingbird shape and causes the level of CagA phosphorylation to increase. Transcriptomics identified 6882 DEG, of which 4052 were upregulated and 2830 were downregulated, among which q-value < 0.05, FC > 2, and FC under the condition of ≤2. Accordingly, 1062 DEG were screened, of which 594 were upregulated and 468 were downregulated. The DEG participated in a total of 151 biological processes, 56 cell components, and 40 molecular functions. The KEGG pathway analysis revealed that the DEG were involved in 21 pathways. The PPI network analysis revealed three highly interconnected clusters. In addition, 30 DEG with the highest degree were analyzed in the TCGA database. As a result, 12 DEG were found to be highly expressed in gastric cancer, while seven DEG were related to the poor prognosis of gastric cancer. RT-qPCR verification results showed that Helicobacter pylori CagA caused up-regulation of BPTF, caspase3, CDH1, CTNNB1, and POLR2A expression. CONCLUSION: The current comprehensive analysis provides new insights for exploring the effect of CagA in human gastric cancer, which could help us understand the molecular mechanism underlying the occurrence and development of gastric cancer caused by Helicobacter pylori.

17.
J Physiol Biochem ; 77(1): 93-104, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33625675

ABSTRACT

Gastric cancer (GC) is one of the most common cancers, with most patients often succumbing to death as a result of tumor metastasis. Recent work has demonstrated that gastrin is closely associated with GC metastasis. However, the specific molecular mechanisms underlying this relationship remain to be unveiled. In this study, we assessed the impact of gastrin and the Wnt/ß-catenin inhibitor XAV939 on the epithelial-mesenchymal transition (EMT) of the SGC-7901 and MKN45 GC cell lines, and we determined that gastrin-17 significantly decreased E-cadherin expression and upregulated the expression of Snail1 and N-cadherin in GC cells. In addition, gastrin 17 also significantly increased the expression of Wnt3α in a dose-dependent manner. Consistent with these results, gastrin-17 promoted GC cell invasion, proliferation, and migration in a dose-dependent fashion, and these effects were inhibited by XAV939. Together, these results indicated that gastrin-17 induced GC cell EMT, migration, and invasion via the Wnt/ß-catenin signaling pathway, which suggests that this gastrin/Wnt/ß-catenin signaling axis may represent a therapeutic target for the prevention of GC metastasis.


Subject(s)
Epithelial-Mesenchymal Transition/drug effects , Gastrins/pharmacology , Snail Family Transcription Factors/metabolism , Stomach Neoplasms/metabolism , Wnt Signaling Pathway/drug effects , Cell Line, Tumor , Cell Movement/drug effects , Cell Proliferation/drug effects , Humans
18.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-886480

ABSTRACT

@#[摘 要] 目的:探讨幽门螺杆菌(Helicobacter pylori, Hp)感染对胃癌细胞共济失调毛细血管扩张突变(ataxia-telangiectasia mutated,ATM)基因表达的影响及其临床意义。方法:从TCGA数据库中获取胃癌相关RNAseq数据,比较ATM基因的表达差异,分析ATM表达与患者临床病理参数的相关性及预后价值,用Kaplan-Meier法进行生存分析,LinkedOmics数据库分析ATM相关基因,用R语言进行GO、KEGG富集分析。选用2019年3月至2019年12月贵州医科大学附属医院12例手术切除的胃癌及癌旁组织标本,以及胃癌细胞系AGS和BGC823,用感染复数40∶1的Hp GZ7菌感染细胞,用免疫组织化学染色法检测胃癌组织中ATM蛋白的表达,qPCR法检测胃癌组织和细胞中ATM mRNA的表达。结果:TCGA数据显示胃癌和Hp感染胃癌组织中ATM miRNA表达水平均显著高于癌旁组织(均P<0.01);胃癌组织中ATM miRNA表达与患者的T分期、AJCC分期等病理参数呈正相关(均P<0.05),ATM高表达时生存率显著降低(P<0.05)。实验检测显示,胃癌组织标本中ATM蛋白的表达水平明显高于癌旁组织(P<0.01);Hp感染胃癌细胞中ATM miRNA表达水平显著高于未感染胃癌细胞(P<0.01)。胃癌中ATM基因与NPAT等12 461个基因呈正相关(P<0.05),与MIF等7 764个基因呈负相关(P<0.05)。GO、KEGG富集分析显示,ATM富集到DNA修复复合体、癌症中的转录失调等信号通路。结论:ATM基因在胃癌组织中高表达,患者生存率随表达水平的增高而降低,其与患者的T分期、AJCC分期等病理参数相关,且Hp感染引起ATM表达水平升高可能是Hp引起胃癌的原因之一。

19.
Oncol Lett ; 20(4): 68, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32863901

ABSTRACT

MicroRNAs (miRs) are associated with cancer metastasis. Aberrant expression levels of members of the miR-30 family have been observed in non-small-cell lung cancer (NSCLC). However, the effects of miR-30 family members on the epithelial-to-mesenchymal transition (EMT) of NSCLC cells and the underlying molecular mechanisms have not yet been fully elucidated. The present study investigated the effects of miR-30 family members on EMT, migration and invasion of NSCLC cells and found that overexpression of these miRs inhibited EMT via decreasing the expression levels of N-cadherin, ß-catenin and SNAI1, along with weakened migration and invasion abilities. Then, XB130 was identified as a downstream target of the miR-30 family members. XB130-knockdown also inhibited EMT of NSCLC cells, whereas ectopic overexpression of XB130 partly rescued the suppressive effects of miR-30c and miR-30d on EMT. In conclusion, miR-30 family members inhibited EMT of NSCLC cells, partially via suppressing XB130 expression levels.

20.
Cell Signal ; 72: 109631, 2020 08.
Article in English | MEDLINE | ID: mdl-32275943

ABSTRACT

Paclitaxel (PTX) is one of standard chemotherapy drug for patients with metastatic castration-resistant prostate cancer (mCRPC). However, PTX resistance leads to treatment failures, for which the underlying molecular mechanisms remain exclusive. In this study, we reported that PTX-induced constant HMGB1 expression and release confers to PTX resistance in mCRPC cells via activating and sustaining c-Myc signaling. PTX upregulated HMGB1 expression and triggered its release in human mCRPC cells. Silencing HMGB1 by RNAi and blocking HMGB1 release by glycyrrhizin or HMGB1 neutralizing antibody sensitized the response of PTX-resistant mCRPC cells to PTX. Release HMGB1 activated c-Myc expression. Inhibiting c-Myc expression by RNAi or c-MyC inhibitor significantly enhance the sensitivity of PTX-resistant CRPC cells to PTX. Therefore, HMGB1/c-Myc axis is critical in the development of PTX resistance, and targeting HMGB1/c-Myc axis would counteract PTX resistance in mCRPC cells.


Subject(s)
Drug Resistance, Neoplasm , HMGB1 Protein/metabolism , Paclitaxel/pharmacology , Prostatic Neoplasms, Castration-Resistant/metabolism , Proto-Oncogene Proteins c-myc/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Culture Media, Conditioned/pharmacology , Drug Resistance, Neoplasm/drug effects , Gene Silencing , Humans , Male , Prognosis , Prostatic Neoplasms, Castration-Resistant/pathology , Survival Analysis , Up-Regulation/drug effects
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