Analysis of key genes and signaling pathways involved in Helicobacter pylori-associated gastric cancer based on The Cancer Genome Atlas database and RNA sequencing data

The prognostic significance and immune characteristics of bone morphogenetic proteins (BMPs) family: A pan-cancer multi-omics analysis

BACKGROUND

Bone morphogenetic proteins (BMPs) are a group of cancer-related proteins vital for development and progression of certain cancer types. Nevertheless, function of BMP family in pan-cancer was not detailedly researched.

OBJECTIVE

Investigating expression pattern and prognostic value of the BMPs family (BMP1-8A and BMP8B) expression across multiple cancer types.

METHODS

Our research integrated multi-omics data for exploring potential associations between BMPs expression and prognosis, clinicopathological characteristics, copy number or somatic mutations, immune characteristics, tumor microenvironment (TME), tumor mutation burden (TMB), microsatellite instability (MSI), immune checkpoint genes and drug sensitivity in The Cancer Genome Atlas (TCGA) tumors. Furthermore, association of BMPs expression and immunotherapy effectiveness was investigated in some confirmatory cohorts (GSE111636, GSE78220, GSE67501, GSE176307, IMvigor210 and mRNA sequencing data from currently undergoing TRUCE01 clinical research included), and biological function and potential signaling pathways of BMPs in bladder cancer (BCa) was explored via Gene Set Enrichment Analysis (GSEA). Eventually, immune infiltration analysis was done via BMPs expression, copy number or somatic mutations in BCa, as well as validation of the expression levels by reverse transcription-quantitative PCR and western blot, and in vitro functional experiments of BMP8A.

RESULTS

Discoveries displayed BMPs expression was related to prognosis, clinicopathological characteristics, mutations, TME, TMB, MSI and immune checkpoint genes of TCGA tumors. Anticancer drug sensitivity analysis displayed BMPs were associated with various drug sensitivities. What's more, it was discovered that expression level of certain BMP family members related to objective response to immunotherapy. By GSEA, we discovered multiple immune-associated functions and pathways were enriched. Immune infiltration analysis on BCa also displayed significant associations among BMPs copy number variations, mutation status and infiltration level of diverse immune cells. Furthermore, differential expression validation and in vitro phenotypic experiment indicated that BMP8A significantly promoted BCa cell proliferation, migration and invasion.

CONCLUSIONS

Current results confirmed significance of both BMPs expression and genomic alteration in the prognosis and treatment of diverse cancer types, and suggested that BMPs may be vital for BCa and can possibly be utilized as biomarkers for immunotherapy.

MIF-Modulated Spinal Proteins Associated with Persistent Bladder Pain: A Proteomics Study

Bladder pain is a prominent symptom in Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS). We studied spinal mechanisms of bladder pain in mice using a model where repeated activation of intravesical Protease Activated Receptor-4 (PAR4) results in persistent bladder hyperalgesia (BHA) with little or no bladder inflammation. Persistent BHA is mediated by spinal macrophage migration inhibitory factor (MIF), and is associated with changes in lumbosacral proteomics. We investigated the contribution of individual spinal MIF receptors to persistent bladder pain as well as the spinal proteomics changes associated with relief of persistent BHA by spinal MIF antagonism. Female mice with persistent BHA received either intrathecal (i.t.) MIF monoclonal antibodies (mAb) or mouse IgG1 (isotype control antibody). MIF antagonism temporarily reversed persistent BHA (peak effect: 2 h), while control IgG1 had no effect. Moreover, i.t. antagonism of the MIF receptors CD74 and C-X-C chemokine receptor type 4 (CXCR4) partially reversed persistent BHA. For proteomics experiments, four separate groups of mice received either repeated intravesical scrambled peptide and sham i.t. injection (control, no pain group) or repeated intravesical PAR4 and: sham i.t.; isotype IgG1 i.t. (15 μg); or MIF mAb (15 μg). L6-S1 spinal segments were excised 2 h post-injection and examined for proteomics changes using LC-MS/MS. Unbiased proteomics analysis identified and relatively quantified 6739 proteins. We selected proteins that showed significant changes compared to control (no pain group) after intravesical PAR4 (sham or IgG i.t. treatment) and showed no significant change after i.t. MIF antagonism. Six proteins decreased during persistent BHA (V-set transmembrane domain-containing protein 2-like confirmed by immunohistochemistry), while two proteins increased. Spinal MIF antagonism reversed protein changes. Therefore, spinal MIF and MIF receptors mediate persistent BHA and changes in specific spinal proteins. These novel MIF-modulated spinal proteins represent possible new targets to disrupt spinal mechanisms that mediate persistent bladder pain.

Lumbosacral spinal proteomic changes during PAR4-induced persistent bladder pain

Repeated intravesical activation of protease-activated receptor-4 (PAR4) in mice results in persistent bladder hyperalgesia (BHA). We investigated spinal proteomic changes associated with persistent BHA. Persistent BHA was induced in female mice by repeated (3x; days 0,2,4; n = 9) intravesical instillation of PAR4 activating peptide (PAR4-AP) while scrambled peptide served as the control (no pain; n = 9) group. The threshold to lower abdominal von Frey stimulation was recorded prior to and during treatment. On day 7, L6-S1 spinal segments were excised and examined for proteomic changes using LC-MS/MS. In-depth, unbiased proteomic tandem-mass tag (TMT) analysis identified and relatively quantified 6739 proteins. We identified significant changes with 29 decreasing and 51 increasing proteins in the persistent BHA group and they were associated with neuroprotection, redox modulation, mitochondrial factors, and neuronal-related proteins. In an additional experiment, decreases in protein levels were confirmed by immunohistochemistry for metallothionein 1/2. Our results show that persistent bladder pain is associated with central (spinal) protein changes. Previous work showed that PAR4-induced bladder pain is mediated, at least in part by spinal MIF. Further functional studies of these top changing proteins may lead to the discovery of novel potential therapeutic targets at the spinal level to modulate persistent bladder pain. Future studies will examine the effect of spinal MIF antagonism on PAR4-induced spinal proteomics associated with persistent bladder pain.

Development of a Signature Based on Eight Metastatic-Related Genes for Prognosis of GC Patients

Gastric cancer (GC) has been a common tumor type with high mortality. Distal metastasis is one of the main causes of death in GC patients, which is also related to poor prognosis. The mRNA profiles and clinical information of GC patients were downloaded from The Cancer Genome Atlas and Gene Expression Omnibus databases. Univariate Cox and LASSO Cox analyses were used to screen the optimal metastasis-related genes (MRGs) to establish a prognostic Risk Score model for GC patients. The nomogram was used to visualize the Risk Score and predict the 1-, 3-, 5-year survival rate. The immune cell infiltration was analyzed by CIBERSORT and the ratio of immune-stromal component was calculated by the ESTIMATE algorithm. A total of 142 differentially expressed genes were identified between metastatic and non-metastatic GC samples. The optimal 8 genes, comprising GAMT (guanidinoacetate N-methyltransferase), ABCB5 (ATP-binding cassette subfamily B member 5), ITIH3 (inter-alpha-trypsin inhibitor heavy chain 3), GDF3 (growth differentiation factor 3), VSTM2L (V-set and transmembrane domain-containing 2 like), CIDEA (cell death inducing DFFA like effector a), NPTX1 (neuronal pentraxin-1), and UMOD (uromodulin), were further screened to establish a prognostic Risk Score, which proved to be an independent prognostic factor. Patients in high-risk group had a poor prognosis. There were significant differences in the proportion of 11 tumor-infiltrating immune cells between high-risk and low-risk subgroups. In addition, the StromalScore, ImmuneScore, and ESTIMATEScore in high-risk group were higher than those in low-risk group, indicating that the tumor microenvironment of the high-risk group was more complex. A Risk Score model based on eight metastasis-related genes could clearly distinguish the prognosis of GC patients. The poor prognosis of patients with high-Risk Score might be associated with the complex tumor microenvironments.

Regulatory network and targeted interventions for CCDC family in tumor pathogenesis

CCDC (coiled-coil domain-containing) is a coiled helix domain that exists in natural proteins. There are about 180 CCDC family genes, encoding proteins that are involved in intercellular transmembrane signal transduction and genetic signal transcription, among other functions. Alterations in expression, mutation, and DNA promoter methylation of CCDC family genes have been shown to be associated with the pathogenesis of many diseases, including primary ciliary dyskinesia, infertility, and tumors. In recent studies, CCDC family genes have been found to be involved in regulation of growth, invasion, metastasis, chemosensitivity, and other biological behaviors of malignant tumor cells in various cancer types, including nasopharyngeal carcinoma, lung cancer, colorectal cancer, and thyroid cancer. In this review, we summarize the involvement of CCDC family genes in tumor pathogenesis and the relevant upstream and downstream molecular mechanisms. In addition, we summarize the potential of CCDC family genes as tumor therapy targets. The findings discussed here help us to further understand the role and the therapeutic applications of CCDC family genes in tumors.

VSTM2L contributes to anoikis resistance and acts as a novel biomarker for metastasis and clinical outcome in ovarian cancer

The majority of patients are diagnosed when ovarian cancer (OC) has metastasized, making surgery and chemotherapy less effective. Thus, there is an urgent need to elucidate the mechanisms underlying metastasis and to further explore novel diagnostic biomarkers of OC metastasis. Here, we conducted a genome-wide CRISPR-Cas9 screen for anoikis resistance to identify key genes associated with OC metastasis. Further, bioinformatic analysis was performed using TCGA and GTEx datasets to explore the genes associated with OC progression and prognosis. After integrated analysis, the V-set and transmembrane domain-containing protein 2-like (VSTM2L) was identified as a crucial gene closely associated with OC metastasis, progression, and prognosis. Further validation using a patient-based cohort suggested that VSTM2L expression was significantly higher in metastatic lesions than in primary lesions. Subsequently, an in vitro assay showed that VSTM2L silencing increased SKOV3 cell death and hampered spheroid formation. Mechanistically, GSEA highlighted that epithelial-mesenchymal transition (EMT)-related pathways was positively associated with VSTM2L expression. Consistently, the validation based on the VSTM2L silence suggested the involvement of VSTM2L in EMT-related TGF-β and NF-κB signaling. Meanwhile, the addition of VSTM2L-containing medium did not provoke those signaling, indicating VSTM2L functions as an intracellular protein to activate TGF-β and NF-κB signaling. In summary, our study revealed that VSTM2L is a novel player involved in anoikis resistance and is a promising biomarker of OC metastasis and prognosis.

Dynamic Network Construction for Identifying Early Warning Signals Based On a Data-Driven Approach: Early Diagnosis Biomarker Discovery for Gastric Cancer

During the development of complex diseases, there is a critical transition from one status to another at a tipping point, which can be an early indicator of disease deterioration. To effectively enhance the performance of early risk identification, a novel dynamic network construction algorithm for identifying early warning signals based on a data-driven approach (EWS-DDA) was proposed. In EWS-DDA, the shrunken centroid was introduced to measure dynamic expression changes in assumed pathway reactions during the progression of complex disease for network construction and to define early warning signals by means of a data-driven approach. We applied EWS-DDA to perform a comprehensive analysis of gene expression profiles of gastric cancer (GC) from The Cancer Genome Atlas database and the Gene Expression Omnibus database. Six crucial genes were selected as potential biomarkers for the early diagnosis of GC. The experimental results of statistical analysis and biological analysis suggested that the six genes play important roles in GC occurrence and development. Then, EWS-DDA was compared with other state-of-the-art network methods to validate its performance. The theoretical analysis and comparison results suggested that EWS-DDA has great potential for a more complete presentation of disease deterioration and effective extraction of early warning information.

RNA sequencing and integrative analysis reveal pathways and hub genes associated with TGFβ1 stimulation on prostatic stromal cells

Objective: Benign prostatic hyperplasia (BPH) is the most common urological disease in elderly men. The transforming growth factor beta 1 (TGFβ1) plays an important role in the proliferation and differentiation of BPH stroma. However, it is not clear yet which important pathways and key genes are the downstream of TGFβ1 acting on prostatic stromal cells.

Methods: GSE132714 is currently the newer, available, and best high-throughput sequencing data set for BPH disease and includes the largest number of BPH cases. We examined the TGFβ1 expression level in BPH and normal prostate (NP) by analyzing the GSE132714 data set as well as carrying out immunohistochemistry of 15 BPH and 15 NP samples. Primary prostatic stromal cells (PrSCs) were isolated from five fresh BPH tissues. RNA sequencing and bioinformatics analysis were used to reveal important pathways and hub genes associated with TGFβ1 stimulation on PrSCs.

Results: TGFβ1 was upregulated in BPH stroma compared to NP stroma. A total of 497 genes (244 upregulated and 253 downregulated) were differentially expressed in PrSCs with and without TGFβ1 stimulation. The Gene Ontology revealed that differentially expressed genes (DEGs) were mainly enriched in progesterone secretion, interleukin-7 receptor binding, and CSF1-CSF1R complex. The Wnt signaling pathway, PI3K−Akt signaling pathway, JAK−STAT signaling pathway, and Hippo signaling pathway were screened based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. FN1, SMAD3, CXCL12, VCAM1, and ICAM1 were selected as hub genes according to the degree of connection from the protein–protein interaction (PPI) network.

Conclusion: This study sheds some new insights into the role of TGFβ1 in BPH stroma and provides some clues for the identification of potential downstream mechanisms and targets.

Construction and validation of a prognostic model for kidney renal clear cell carcinoma based on podocyte-associated genes

Background

As the most common renal malignancy, kidney renal clear cell carcinoma (KIRC) has a high prevalence and death rate as well as a poor response to treatment. Developing an efficient prognostic model is essential for accurately predicting the outcome and therapeutic benefit of KIRC patients.

Methods

Gene expression profiles of podocyte‐associated genes (PAGs) were obtained from The Cancer Genome Atlas and GEO datasets. Cox regression and Lasso regression analyses were then used for filtering prognosis‐associated PAGs. Risk score (RS) was computed from these genetic characteristics. Kaplan–Meier analysis and receiver operating characteristic (ROC) curves were applied for ascertaining the prognostic value. Stratified analysis was used to sufficiently validate model performance. Concordance index was used to compare the predictive ability of different models. Immuno‐infiltration analysis and immunophenoscore were utilized for the prediction of patient reaction to immune checkpoint inhibitors (ICIs).

Results

WT1, ANLN, CUBN, OSGEP, and RHOA were significantly associated with KIRC prognosis. Prognostic analysis indicated that high‐RS patients have a significantly poorer outcome. Cox regression analysis demonstrated a potential for RS to be an independent prognostic factor. Pathway enrichment results indicated a lower enrichment of cancer‐related biological pathways in the low‐RS subgroup. Immune infiltration analysis and IPS demonstrated greater responsiveness to ICIs in the high RS group.

Conclusions

This podocyte‐associated KIRC prognostic model can effectively predict KIRC prognosis and immunotherapy response, which may help to provide clinicians with more effective treatment strategies.

Positive H. pylori status predicts better prognosis of non-cardiac gastric cancer patients: results from cohort study and meta-analysis

BACKGROUND

Previous researches have associated Helicobacter pylori (H. pylori) with a prognosis of gastric cancer (GC), however, without a concert conclusion. This study aimed to study this issue further by a prospective cohort study and a meta-analysis.

METHODS

Histologically diagnosed gastric cancer (GC) patients were recruited into the primary prospective cohort study between January 2009 to December 2013. All the patients were followed-up periodically to record information on post-surgery therapy and overall survival status. The pre-surgery status of H. pylori was measured by enzyme-linked immunosorbent assay. A meta-analysis was conducted after retrieving related researches in the databases of PubMed and Embase up to April 2020. Pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were summarized to validate the relationship between H. pylori infection and the survival time of GC patients. I² statistics and Q test were used to assess the heterogeneity. Sensitivity analyses were performed using Galbraith's plot, leave-one-out analysis, subgroup analyses and meta-regression to explore the sources of heterogeneity and the stability of the summary results.

RESULTS

A total of 743 GC patients with radical tumorectomy were included prospectively and 516 (69.4%) were positive on H. pylori. H. pylori-positive patients tended to survive longer than -negative ones (HR 0.92, 95%CI: 0.74-1.15), though the tendency was not statistically significant. Cohort studies on the prognosis of GC were retrieved comprehensively by assessing the full-text and 59 published studies, together with the result of our study, were included in the further meta-analysis. The summarized results related the positive status of H. pylori to better overall survival (HR 0.81, 95%CI: 0.72-0.90) and disease-free survival (HR 0.83, 95%CI: 0.67-0.99). Results from subgroup analyses indicated that the pooled magnitude of this association was relatively lower in studies not referring to H. pylori in title and abstract.

CONCLUSIONS

In conclusion, gastric cancer patients with H. pylori have a better prognosis than patients of H. pylori negative. More stringent surveillance strategies may be necessary for patients with H. pylori negative at cancer diagnosis.

Pan-Cancer Analysis Reveals the Multidimensional Expression and Prognostic and Immunologic Roles of VSTM2L in Cancer

Immunotherapy can improve survival in a variety of cancers by modulating the interaction between tumors and the tumor immune microenvironment (TIME). V-set and transmembrane domain containing 2 like (VSTM2L) regulates interleukin (IL)-4 signaling pathway—which involves immune-related factors—and has been linked to some cancers. However, the expression profile and prognostic significance of VSTM2L in different cancers as well as its relationship to the TIME are not known. This study investigated the pan-cancer expression profile, prognostic value, and immunologic relevance of VSTM2L. VSTM2L expression in different cancers was analyzed using the Cancer Cell Line Encyclopedia (CCLE), Human Protein Atlas (HPA), Tumor Immune Estimation Resource (TIMER), The Cancer Genome Atlas (TCGA), and Genotype–Tissue Expression (GTEx) portal. We examined the association between VSTM2L expression and clinical outcomes by Kaplan–Meier and Cox regression analyses using TCGA and Kaplan–Meier Plotter, and the results were validated in a Gene Expression Omnibus cohort. The correlations between VSTM2L expression and immune cell infiltration, immunomodulators, tumor mutation burden (TMB), microsatellite instability (MSI), and immune and stromal scores across cancers were analyzed using TCGA, TIMER, and Tumor–Immune System Interactions and Drugbank databases (TISIDB). The results showed that VSTM2L expression varied across cancers and its aberrant expression was associated with clinical outcomes: upregulation of VSTM2L was positively associated with advanced stage and reduced overall survival (OS), disease-specific survival (DSS), progression-free interval (PFI), and disease-free interval (DFI) in stomach adenocarcinoma (STAD); and its upregulation was associated with early-stage disease and improved OS, DSS, PFI, and DFI in kidney renal papillary cell carcinoma (KIRP). VSTM2L expression level was correlated with immune cell infiltration, expression of immunomodulators, TMB, MSI, and immune and stromal scores in multiple cancers. In conclusion, VSTM2L has prognostic value in various cancers and can predict both poor (STAD) and good (KIRP) outcomes. The relationship between VSTM2L expression and immune markers suggests a role in modulating the TIME.

Kinases and therapeutics in pathogen mediated gastric cancer

INTRODUCTION

Many pathogens have coexisted with humans for millennia and can cause chronic inflammation which is the cause of gastritis. Gastric cancer (GC) is associated with 8.8% of cancer related deaths, making it one of the leading causes of cancer related deaths worldwide. This review is intended to give brief information about Helicobacter pylori (H. pylori), Epstein-Barr virus (EBV), human cytomegalovirus (HCMV) role in GC and associated kinases. These organisms can trigger multiple cellular pathways aiming for unnatural cellular proliferation, apoptosis, migration and inflammatory response. Kinases also can activate and deactivate the signalling leading to aforementioned pathways. Therefore, studying kinases is inevitable.

MATERIAL AND METHODS

This review is the comprehensive collection of information from different data sources such as journals, book, book chapters and verified online information.

CONCLUSION

Kinase amplifications could be used as diagnostic, prognostic, and predictive biomarkers in various cancer types. Hence targeting kinase and related signalling molecules could be considered as a potential approach to prevent cancer through these organisms. Here we summarize the brief information about the role of kinases, signalling and their therapeutics in GC concerning H. pylori, EBV and HCMV.

Upregulation of oncogene Activin A receptor type I by Helicobacter pylori infection promotes gastric intestinal metaplasia via regulating CDX2

BACKGROUND

Activin A receptor type I (ACVR1) is involved in tumorigenesis. However, the underlying molecular mechanisms of ACVR1 in gastric cancer (GC) and its association with Helicobacter pylori remained unclear.

MATERIALS AND METHODS

The Cancer Genome Atlas (TCGA) and Gene Expression Profiling Interactive Analysis (GEPIA) database were utilized to explore the ACVR1 expression in GC and normal control and its association with survival. The ACVR1 was knocked out using CRISPR/Cas-9; RNA sequencing analysis was performed in AGS cells with ACVR1 knockout and normal control. Functional experiments (CCK-8, colony-forming, and transwell assays) were conducted to demonstrate the role of ACVR1 in cell proliferation, invasion, and metastasis. H. pylori-infected C57/BL6 models were established. ACVR1, p-Smad1/5, and CDX2 were detected in AGS cells cocultured with H. pylori strains. The CDX2 and key elements of BMP signaling pathway were detected in AGS cells with ACVR1 knockout and normal control. In addition, Immunohistochemistry was performed to detect the ACVR1 and CDX2 expression in gastric samples.

RESULTS

ACVR1 expression was higher in GC than normal control from TCGA, GEPIA, and samples collected from our hospital (p < 0.05). ACVR1 promoted cell proliferation, migration, and invasion in vitro. Both cagA⁺ and cagA^- H. pylori could upregulate the expression ACVR1 (p < 0.05). Downregulation of ACVR1 inhibited the H. pylori-induced cell proliferation, migration, and invasion (p < 0.05). H. pylori increased the expression of p-Smad 1/5 and CDX2. The CDX2 and key elements of BMP signaling pathway were downregulated in AGS cells with ACVR1 knockout. ACVR1 and CDX2 were upregulated in the stage of intestinal metaplasia (IM). Moreover, ACVR1 and CDX2 expressions were higher in H. pylori-positive group than H. pylori-negative group (p < 0.05).

CONCLUSION

Our data indicate that H. pylori infection increases ACVR1 expression, promoting gastric IM via regulating CDX2, which is an essential step in H. pylori carcinogenesis.

Recognition of DNA Methylation Molecular Features for Diagnosis and Prognosis in Gastric Cancer

Background: The management of gastric cancer (GC) still lacks tumor markers with high specificity and sensitivity. The goal of current research is to find effective diagnostic and prognostic markers and to clarify their related mechanisms.

Methods: In this study, we integrated GC DNA methylation data from publicly available datasets obtained from TCGA and GEO databases, and applied random forest and LASSO analysis methods to screen reliable differential methylation sites (DMSs) for GC diagnosis. We constructed a diagnostic model of GC by logistic analysis and conducted verification and clinical correlation analysis. We screened credible prognostic DMSs through univariate Cox and LASSO analyses and verified a prognostic model of GC by multivariate Cox analysis. Independent prognostic and biological function analyses were performed for the prognostic risk score. We performed TP53 correlation analysis, mutation and prognosis analysis on eleven-DNA methylation driver gene (DMG), and constructed a multifactor regulatory network of key genes.

Results: The five-DMS diagnostic model distinguished GC from normal samples, and diagnostic risk value was significantly correlated with grade and tumor location. The prediction accuracy of the eleven-DMS prognostic model was verified in both the training and validation datasets, indicating its certain potential for GC survival prediction. The survival rate of the high-risk group was significantly lower than that of the low-risk group. The prognostic risk score was an independent risk factor for the prognosis of GC, which was significantly correlated with N stage and tumor location, positively correlated with the VIM gene, and negatively correlated with the CDH1 gene. The expression of CHRNB2 decreased significantly in the TP53 mutation group of gastric cancer patients, and there were significant differences in CCDC69, RASSF2, CHRNB2, ARMC9, and RPN1 between the TP53 mutation group and the TP53 non-mutation group of gastric cancer patients. In addition, CEP290, UBXN8, KDM4A, RPN1 had high frequency mutations and the function of eleven-DMG mutation related genes in GC patients is widely enriched in multiple pathways.

Conclusion: Combined, the five-DMS diagnostic and eleven-DMS prognostic GC models are important tools for accurate and individualized treatment. The study provides direction for exploring potential markers of GC.

Key Candidate Genes - VSIG2 of Colon Cancer Identified by Weighted Gene Co-Expression Network Analysis

Background

Colon adenocarcinoma (COAD) is one of the most common malignancies. To identify candidate genes that may be involved in colon adenocarcinoma development and progression, weighted gene co-expression network analysis (WGCNA) was used to construct gene co-expression networks to explore associations between gene sets and clinical features and to identify candidate biomarkers. Moreover, we intend to make a preliminary exploration on it.

Methods

Gene expression profiles and clinical information were collected from The Cancer Genome Atlas COAD database for analysis. The gene expression profiles of GSE106582 and GSE110224 were screened from the Gene Expression Omnibus database for verification. WGCNA analysis, functional pathway enrichment analysis, and prognosis analysis were performed on three databases. Target genes were selected from the key genes for experimental verification and research.

Results

Key genes obtained by WGCNA analysis were mainly enriched in key functions and pathways such as drug metabolism, steroid hormones, and retinol metabolism. A total of four prognostic genes were screened out: SELENBP1, NAT2, VSIG2, and CES2. VSIG2 was selected as the target gene for experimental verification, and its encoded protein was found to be mainly expressed in immune cells. Its expression was positively correlated with immune infiltration.

Conclusions

VSIG2 was shown to be associated with immune invasion and antigen presentation in COAD, suggesting it plays an important role in COAD development and progression. It could be used as a potential biomarker or therapeutic target for COAD.

Development of a four-gene prognostic model for clear cell renal cell carcinoma based on transcriptome analysis

This study aimed to develop a prognostic model for clear cell renal cell carcinoma (ccRCC) based on transcriptome analysis. We screened Gene Expression Omnibus (GEO) database and the Cancer Genome Atlas (TCGA) database for gene expression data and clinical characteristics of ccRCC. After differentially expression analysis, we identified 533 key genes of the development of ccRCC. Next, a weighted gene co-expression network analysis (WGCNA) was executed to investigate the association between differentially expressed genes and clinical characteristics. Then, based on protein-protein interaction (PPI) network, least absolute shrinkage and selection operator (LASSO) regression and Cox regression, a four-gene (COL4A5, ABCB1, NR3C2 and PLG) prognostic model has been constructed in TCGA training cohort. Finally, we examined the predictive power of this model with survival analysis and receiver operating characteristic (ROC) curve both in training cohort and in validation cohorts. And we found this model was significantly correlated with infiltrating immune cells. The four-gene prognosis model could be a potential prediction tool with high accuracy and reliability for ccRCC patients.

Unlike Its Paralog LEDGF/p75, HRP-2 Is Dispensable for MLL-R Leukemogenesis but Important for Leukemic Cell Survival

HDGF-related protein 2 (HRP-2) is a member of the Hepatoma-Derived Growth Factor-related protein family that harbors the structured PWWP and Integrase Binding Domain, known to associate with methylated histone tails or cellular and viral proteins, respectively. Interestingly, HRP-2 is a paralog of Lens Epithelium Derived Growth Factor p75 (LEDGF/p75), which is essential for MLL-rearranged (MLL-r) leukemia but dispensable for hematopoiesis. Sequel to these findings, we investigated the role of HRP-2 in hematopoiesis and MLL-r leukemia. Protein interactions were investigated by co-immunoprecipitation and validated using recombinant proteins in NMR. A systemic knockout mouse model was used to study normal hematopoiesis and MLL-ENL transformation upon the different HRP-2 genotypes. The role of HRP-2 in MLL-r and other leukemic, human cell lines was evaluated by lentiviral-mediated miRNA targeting HRP-2. We demonstrate that MLL and HRP-2 interact through a conserved interface, although this interaction proved less dependent on menin than the MLL-LEDGF/p75 interaction. The systemic HRP-2 knockout mice only revealed an increase in neutrophils in the peripheral blood, whereas the depletion of HRP-2 in leukemic cell lines and transformed primary murine cells resulted in reduced colony formation independently of MLL-rearrangements. In contrast, primary murine HRP-2 knockout cells were efficiently transformed by the MLL-ENL fusion, indicating that HRP-2, unlike LEDGF/p75, is dispensable for the transformation of MLL-ENL leukemogenesis but important for leukemic cell survival.

High Expression of VSTM2L Induced Resistance to Chemoradiotherapy in Rectal Cancer through Downstream IL-4 Signaling

Background

Preoperative chemoradiotherapy (pCRT) is a common and essential therapeutic strategy for patients with locally advanced rectal cancer (LARC), but poor tumor response and therapeutic resistance to chemoradiotherapy have appeared usually among persons and affected those patients' survival prognosis. The resistance to chemoradiotherapy in rectal cancer is difficult to predict. This study was aimed at evaluating the role of V-set and transmembrane domain containing 2 like protein (VSTM2L) in resistance to chemoradiotherapy in rectal cancer.

Methods

Analysis of the GEO profiling datasets of rectal cancer patients receiving pCRT disclosed that VSTM2L as a candidate gene was significantly upregulated in nonresponders of rectal cancer with pCRT. The mRNA and protein expression of VSTM2L was detected by quantitate real-time PCR, western blotting, and immunohistochemistry in six rectal cancer biopsy tissues before pCRT. Furthermore, the rectal cancer patient-derived organoids were cultured to evaluate the association of VSTM2L expression and tumor response to CRT. Overexpression of VSTM2L in cancer cells treated with CRT was analyzed for the function of cell proliferation and viability, clone formation, DNA damage repair, and apoptosis ability. The GSEA and RNA-sequence analysis were used to find the downstream mechanism of VSTM2L overexpression in cells treated with CRT.

Results

The mRNA levels of VSTM2L were significantly downregulated in normal rectal tissues compared to tumor tissues and were upregulated in nonresponders of rectal cancer patients receiving pCRT and positively correlated with poor survival prognosis from GEO datasets. High expression of VSTM2L was significantly associated with tumor regression after pCRT (P = 0.030). Moreover, high expression of VSTM2L reduced γ-H2AX expression in rectal cancer patient-derived organoids treated with CRT. The overexpression of VSTM2L in colorectal cancer cells induced resistance to CRT via promoting cell proliferation and inhibiting apoptosis. The molecular mechanism revealed that the overexpression of VSTM2L induced resistance to CRT through downstream IL-4 signaling affecting the progress of cell proliferation and apoptosis.

Conclusion

The high expression of VSTM2L induced resistance to CRT, and adverse survival outcomes served as a prognostic factor in patients with rectal cancer receiving pCRT, suggesting that VSTM2L high expression may be a potential resistant predictable biomarker for LARC patients receiving pCRT.

Purification of Total RNA from Stomach Tissue Biopsies

In order to further our understanding of the physiological consequences of Helicobacter pylori infection , analysis of clinical tissue specimens is required. To this end, RNA is frequently isolated from stomach biopsies of H. pylori-infected patients and compared to samples from uninfected controls to monitor gene expression using molecular methods such as reverse-transcription real-time PCR, microarrays, and next-generation sequencing. The successful purification of sufficient quantities of high-quality RNA is essential for accurate and reproducible downstream analysis. This chapter describes the key steps for high-quality RNA purification from human tissue samples, including sample collection and storage, tissue disruption and lysis, RNA purification, and assessment of RNA yield and quality.

Identifying a Potential Key Gene, TIMP1, Associated with Liver Metastases of Uveal Melanoma by Weight Gene Co-Expression Network Analysis

Purpose

Uveal melanoma (UM) is a primary intraocular tumor in adults, with a high percentage of metastases to the liver. Identifying potential key genes may provide information for early detection and prognosis of UM metastasis.

Patients and Methods

Differentially expressed genes (DEGs) were identified using the GSE22138 dataset. Weighted gene co-expression network analysis was used to construct co-expression modules. Functional enrichment analysis was performed for DEGs and genes of key modules. Hub genes were screened by co-expression network and protein–protein interaction network (PPI), and validated by survival analysis in The Cancer Genome Atlas database. Gene set enrichment analysis (GSEA) was used to explore the potential metastasis mechanism of UM. Transient transfection was used to investigate the effect of TIMP1 on the proliferation, migration, and invasion of UM cells.

Results

In total, 552 DEGs were identified between primary and metastatic UM and mainly enriched in extracellular matrix, cellular senescence and focal adhesion pathway. A weighted gene co‑expression network was built to identify key gene modules associated with UM metastasis (n=36). The turquoise module is positively correlated with metastasis and genes in this module were mainly enriched in peptidyl-tyrosine autophosphorylation and regulation of organ growth. The hub gene TIMP1 was screened out by co-expression network and PPI analysis. High expression of TIMP1 was related to p53 pathway by GSEA and short overall survival time. Experimental results indicated that overexpression of TIMP1 inhibited the proliferation and migration, while it had no significant effect on invasion of UM cells.

Conclusion

Our study indicates that TIMP1 might be associated with metastasis in UM, which might have important significance for identifying patients with high risk of metastasis and predicting the prognosis of UM.

Global gene expression profiling of blast lung injury of goats exposed to shock wave

PURPOSE

Blast lung injury (BLI) is the most common damage resulted from explosion-derived shock wave in military, terrorism and industrial accidents. However, the molecular mechanisms underlying BLI induced by shock wave are still unclear.

METHODS

In this study, a goat BLI model was established by a fuel air explosive power. The key genes involved in were identified. The goats of the experimental group were fixed on the edge of the explosion cloud, while the goats of the control group were 3 km far away from the explosive environment. After successful modeling for 24 h, all the goats were sacrificed and the lung tissue was harvested for histopathological observation and RNA sequencing. Gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) analysis were performed to identify the main enriched biological functions of differentially expressed genes (DEGs). Quantitative real-time polymerase chain reaction (qRT-PCR) was used to verify the consistency of gene expression.

RESULTS

Of the sampled goat lungs, 895 genes were identified to be significantly differentially expressed, and they were involved in 52 significantly enriched GO categories. KEGG analysis revealed that DEGs were highly enriched in 26 pathways, such as cytokine-cytokine receptor interaction, antifolate resistance, arachidonic acid metabolism, amoebiasis and bile secretion, JAK-STAT, and IL-17 signaling pathway. Furthermore, 15 key DEGs involved in the biological processes of BLI were confirmed by qRT-PCR, and the results were consistent with RNA sequencing.

CONCLUSION

Gene expression profiling provide a better understanding of the molecular mechanisms of BLI, which will help to set strategy for treating lung injury and preventing secondary lung injury induced by shock wave.

Genome-wide identification of CpG island methylator phenotype related gene signature as a novel prognostic biomarker of gastric cancer

Background

Gastric cancer (GC) is one of the most fatal cancers in the world. Results of previous studies on the association of the CpG island methylator phenotype (CIMP) with GC prognosis are conflicting and mainly based on selected CIMP markers. The current study attempted to comprehensively assess the association between CIMP status and GC survival and to develop a CIMP-related prognostic gene signature of GC.

Methods

We used a hierarchical clustering method based on 2,082 GC-related methylation sites to stratify GC patients from the cancer genome atlas into three different CIMP subgroups according to the CIMP status. Gene set enrichment analysis, tumor-infiltrating immune cells, and DNA somatic mutations analysis were conducted to reveal the genomic characteristics in different CIMP-related patients. Cox regression analysis and the least absolute shrinkage and selection operator were performed to develop a CIMP-related prognostic signature. Analyses involving a time-dependent receiver operating characteristic (ROC) curve and calibration plot were adopted to assess the performance of the prognostic signature.

Results

We found a positive relationship between CIMP and prognosis in GC. Gene set enrichment analysis indicated that cancer-progression-related pathways were enriched in the CIMP-L group. High abundances of CD8+ T cells and M1 macrophages were found in the CIMP-H group, meanwhile more plasma cells, regulatory T cells and CD4+ memory resting T cells were detected in the CIMP-L group. The CIMP-H group showed higher tumor mutation burden, more microsatellite instability-H, less lymph node metastasis, and more somatic mutations favoring survival. We then established a CIMP-related prognostic gene signature comprising six genes (CST6, SLC7A2, RAB3B, IGFBP1, VSTM2L and EVX2). The signature was capable of classifying patients into high‐and low‐risk groups with significant difference in overall survival (OS; p < 0.0001). To assess performance of the prognostic signature, the area under the ROC curve (AUC) for OS was calculated as 0.664 at 1 year, 0.704 at 3 years and 0.667 at 5 years. When compared with previously published gene-based signatures, our CIMP-related signature was comparable or better at predicting prognosis. A multivariate Cox regression analysis indicated the CIMP-related prognostic gene signature was an independent prognostic indicator of GC. In addition, Gene ontology analysis indicated that keratinocyte differentiation and epidermis development were enriched in the high-risk group.

Conclusion

Collectively, we described a positive association between CIMP status and prognosis in GC and proposed a CIMP-related gene signature as a promising prognostic biomarker for GC.

Identification of DEGs and transcription factors involved in H. pylori-associated inflammation and their relevance with gastric cancer

Background

Previous studies have indicated that chronic inflammation linked to H. pylori infection is the leading causes for gastric cancer (GC). However, the exact mechanism is not entirely clear until now.

Purpose

To identify the key molecules and TFs involved in H. pylori infection and to provide new insights into H. pylori-associated carcinogenesis and lay the groundwork for the prevention of GC.

Results

GO and KEGG analysis revealed that the DEGs of Hp⁺-NAG were mainly associated with the immune response, chemokine activity, extracellular region and rheumatoid arthritis pathway. The DEGs of Hp⁺-AG-IM were related to the apical plasma membrane, intestinal cholesterol absorption, transporter activity and fat digestion and absorption pathway. In Hp⁺-NAG network, the expression of TNF, CXCL8, MMP9, CXCL9, CXCL1, CCL20, CTLA4, CXCL2, C3, SAA1 and FOXP3, JUN had statistical significance between normal and cancer in TCGA database. In Hp⁺-AG-IM network the expression of APOA4, GCG, CYP3A4, XPNPEP2 and FOXP3, JUN were statistically different in the comparison of normal and cancer in TCGA database. FOXP3 were negatively associated with overall survival, and the association for JUN was positive.

Conclusion

The current study identified key DEGs and their transcriptional regulatory networks involved in H. pylori-associated NAG, AG-IM and GC and found that patients with higher expressed FOXP3 or lower expressed JUN had shorter overall survival time. Our study provided new directions for inflammation-associated oncogenic transformation involved in H. pylori infection.

Mechanism Analysis of Coix Seed in Gastric Cancer Treatment Based on Biological Network Modules

Coix seed, the mature seed of Coix lacryma-jobi L., is a traditional herb widely used in various cancer adjuvant treatments; however, its mechanism is unknown. The aim of this study was to reveal the multitarget mechanisms of Coix seed in the treatment of gastric cancer (GC) by biological network and modular analysis methods. Forty-one ingredients and 482 targets of Coix seed and 165 GC-related genes were obtained from databases. Twelve on-target genes ( AICDA, CASP3, EP300, ERBB2, FGFR2, IL12A, IL12B, IL1B, LOX, TJP1, TP53, and TRIB3) of Coix seed overlapped with GC-related genes. Using compound-target and protein–protein interaction network analyses, we discovered the core targets of Coix seed. Markov cluster algorithm-based modular analysis identified 5 potential module targets of Coix seed for GC. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis demonstrated the vast actions of Coix seed, which involve pathways in cancer, the cell cycle, receptor signal transduction, deoxyribonucleic acid damage response, transcriptional regulation, apoptosis, and cell connections. This study elucidated the potential mechanisms of Coix seed on GC, which may lead to the development of an effective drug. Additionally, this study showed the feasibility of network and modular analysis methods to investigate traditional Chinese medicinal herbal mechanisms and may provide a new angle for further research in the field of anticancer mechanisms and multitarget drugs.

Transcriptome hallmarks in Helicobacter pylori infection influence gastric cancer and MALT lymphoma

Aim: Altered long noncoding RNA (lncRNA) and mRNA is vital in the progression from Helicobacter pylori (H. pylori, HP) infection to gastric cancer (GC) and mucosa-associated lymphoid tissue (MALT) lymphoma. Materials & methods: Five independent Gene Expression Omnibus datasets (GSE5081, GSE84433, GSE15459, GSE66229 and GSE25638) were included in our study. Results: Differentially expressed lncRNAs and mRNAs in both H. pylori-positive gastritis and GC tissues were identified. Using two GC cohorts, the H. pylori-related mRNA DYNC1I1 and MMP7 were independent predictors of overall survival. Moreover, the expressions of lncRNA GHRLOS and 44 mRNAs were significantly changed in gastric MALT lymphoma patients. Conclusion: The lncRNA/mRNA response to H. pylori infection in gastritis and GC influence the outcome of GC and progression of MALT lymphoma.

Identification of key candidate genes for colorectal cancer by bioinformatics analysis

Colorectal cancer (CRC) is one of the most common cancers of the digestive tract. Although numerous studies have been conducted to elucidate the cause of CRC, the exact mechanism of CRC development remains to be determined. To identify candidate genes that may be involved in CRC development and progression, the microarray datasets GSE41657, GSE77953 and GSE113513 were downloaded from the Gene Expression Omnibus database. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes were used for functional enrichment analysis of differentially expressed genes (DEGs). A protein-protein interaction network was constructed, and the hub genes were subjected to module analysis and identification using Search Tool for the Retrieval of Interacting Genes/Proteins and Cytoscape. A total of 142 DEGs were identified, with enriched functions and pathways in the ‘cell cycle’, ‘cell proliferation’, ‘the mitotic cell cycle’ and ‘one-carbon metabolic process’. In addition, 10 hub genes were identified, and functional analysis indicated that these genes are mainly enriched in ‘cell division’, ‘cell cycle’ and functions associated with nucleotide binding processes. Survival analysis demonstrated that DNA topoisomerase II α, cyclin-dependent kinase 1 and CDC28 protein kinase regulatory subunit 2 may be involved in cancer invasion or recurrence. The DEGs identified in the present study may help explain the molecular mechanisms of CRC development and progression.

Identification of CXCL13 as a potential biomarker in clear cell renal cell carcinoma via comprehensive bioinformatics analysis

BACKGROUND

Clear cell renal cell carcinoma (ccRCC) is one of the most common malignancies in urinary system. However, there are still no reliable biomarkers for the diagnosis and prognosis of ccRCC. In this study, we aimed to screen candidate biomarkers and potential therapeutic targets for ccRCC.

METHODS

Differentially expressed genes (DEGs) were screened using NetworkAnalyst. Protein-protein interaction (PPI) network and weighted gene co-expression network analysis (WGCNA) were utilized to identify hub genes. Then, we assessed the prognostic and diagnostic values of hub genes to screen candidate biomarkers. Gene Set Enrichment Analysis (GSEA) was applied to reveal potential mechanisms of candidate biomarkers in ccRCC. Oncomine database and The Human Protein Atlas were used to verify the expression of candidate biomarkers online. In addition, qRT-PCR, Enzyme linked immunosorbent assay (ELISA) and Immunohistochemistry (IHC) assays were performed to validate the expression level of candidate biomarkers in ccRCC cells and tissues.

RESULTS

A total of 771 genes were identified as DEGs. GO function analysis showed that DEGs were mostly enriched in excretion, apical part of cell and monovalent inorganic cation transmembrane transporter activity. KEGG pathway analysis demonstrated that DEGs were mostly involved in Neuroactive ligand-receptor interaction. After utilizing PPI network and WGCNA, nine genes (IFNG, CXCR3, PMCH, CD2, FASLG, CXCL13, CD8A, CD3D and GZMA) were identified as the hub genes. Moreover, survival analysis exhibited that high expression of CXCL13 predicted poor survival in both overall survival (OS) and disease free survival (DFS). The ROC curves indicated that CXCL13 could distinguish ccRCC samples from normal kidney samples. High expression of CXCL13 group was mostly associated with RB and MEL18 pathways by GSEA. Furthermore, qRT-PCR, ELISA and IHC results showed that the expression of CXCL13 was elevated in ccRCC.

CONCLUSIONS

Our study illustrated that CXCL13 had good diagnostic and prognostic value, which may become a candidate biomarker and therapeutic target for ccRCC.

Inflammatory responses induced by Helicobacter pylori on the carcinogenesis of gastric epithelial GES‑1 cells

Helicobacter pylori (HP) is a pathogenic bacterium associated with chronic gastritis, gastric ulcer and gastric cancer. In the present study, the primary carcinogenesis process of normal gastric epithelial cells (GES‑1) infected with HP was investigated. It was determined that infected gastric mucosal epithelial GES‑1 cells secreted increased interleukin‑8 (IL‑8) and IL‑23, and exhibited enhanced expression of inducible nitric oxide synthase and cyclooxygenase‑2, inducing inflammatory reactions and resulting in apoptosis. The bacterial infection significantly increased the expression of carcinogenesis‑associated genes, including p16, c‑Myc, p53 and p21, as well as the expression of cell surface signaling molecules cluster of differentiation 44 (CD44) and CD54 in GES‑1 cells or tissues of patients with gastritis and gastric cancer in vitro or in vivo. Simultaneously, the migration and invasion abilities of normal gastric epithelial GES‑1 cells were increased following HP infection. These observations demonstrated that the inflammatory response of HP infection could cause normal gastric epithelial cells to undergo significant cancerous reactions, indicating that HP is a risk factor for gastric cancer.

Downregulation of tumor suppressor RACK1 by Helicobacter pylori infection promotes gastric carcinogenesis through the integrin β-1/NF-κB signaling pathway

Receptor of activated protein kinase C 1 (RACK1) is downregulated in gastric cancer and is involved in modulating NF-κB signaling pathway activity. However, the underlying molecular mechanisms regulating RACK1 expression are unclear. In this study, we demonstrated that downregulated expression of RACK1 was observed in gastric cancer tissue compared to adjacent normal tissue and was correlated with poor prognosis in patients. Helicobacter pylori (H. pylori) infection downregulated RACK1 expression in concert with canonical NF-κB signaling pathway activation in vivo and in vitro. RACK1 overexpression suppressed NF-κB signaling pathway activation as well as the release of downstream proinflammatory cytokines. In addition, RACK1 downregulation increased integrin β-1 expression, while integrin β-1 silencing decreased NF-κB signaling activation. Moreover, H. pylori infection downregulated RACK1 but upregulated integrin β-1 expression at the precancerous lesion stages in human subjects. Our data indicate that H. pylori infection promotes the upregulation of integrin β-1 expression via downregulation of RACK1 expression, which subsequently leads to the elevated activation of the NF-κB signaling pathway, an essential step in H. pylori-induced carcinogenesis.

Protective effect of mulberry (Morus atropurpurea) fruit against diphenoxylate-induced constipation in mice through the modulation of gut microbiota

The protective effect of mulberry (Morus atropurpurea) fruit against diphenoxylate-induced constipation in mice through the modulation of gut microbiota.