Tyrosine Kinases in Helicobacter pylori Infections and Gastric Cancer

Novel carbonic anhydrase inhibitors for the treatment of Helicobacter pylori infection

INTRODUCTION

Helicobacter pylori, the causative agent of peptic ulcer, gastritis, and gastric cancer encodes two carbonic anhydrases (CA, EC 4.2.1.1) belonging to the α- and β-class (HpCAα/β), which have been validated as antibacterial drug targets. Acetazolamide and ethoxzolamide were also clinically used for the management of peptic ulcer.

AREAS COVERED

Sulfonamides were the most investigated HpCAα/β compounds, with several low nanomolar inhibitors identified, some of which also crystallized as adducts with HpCAα, allowing for the rationalization of the structure-activity relationship. Few data are available for other classes of inhibitors, such as phenols, sulfamides, sulfamates, dithiocarbamates, arylboronic acids, some of which showed effective in vitro inhibition and for phenols, also inhibition of planktonic growth, biofilm formation, and outer membrane vesicles spawning.

EXPERT OPINION

Several recent drug design studies reported selenazoles incorporating seleno/telluro-ethers attached to benzenesulfonamides, hybrids incorporating the EGFR inhibitor erlotinib and benzenesulfonamides, showing KIs < 100 nM against HpCAα and MICs in the range of 8-16 µg/mL for the most active derivatives. Few drug design studies for non-sulfonamide inhibitors were performed to date, although inhibition of these enzymes may help the fight of multidrug resistance to classical antibiotics which emerged in the last decades also for this bacterium.

A descriptive analysis of gastric cancer with an immunohistochemical Study of Ki67 and p53 as prognostic factors.: Bahrain experience

OBJECTIVES

To describe the increasing number of gastric cancer cases at Bahrain Defense Force Hospital with implementation of immunohistochemistry markers as prognostic factors.

METHODS

This study included histologically confirmed malignant gastric tumors diagnosed at Bahrain Defense Force Hospital from January 2009 to June 2019. Various epidemiological and pathological data were abstracted and recorded with immunohistochemical analysis of the proliferation marker Ki67 and cell-cycle regulator p53 as prognostic factors.

RESULTS

A total of 53 patients with gastric cancer were included in the study, with mean age of 59.75 ± 12.9 years. The typical histological types were signet ring cell adenocarcinoma (68%) and intestinal type adenocarcinoma (17%). Helicobacter pylori and intestinal metaplasia were significantly associated with gastric cancer (p<0.01). The studied population's mortality was 39 (74%). The Ki67 proliferation index showed a mean and standard deviation of 67.09 ± 16.338, with a higher mortality rate in patients with low Ki67 but no difference in survival time. No statistically significant association was found between clinicopathological findings with p53 immunostaining positivity.

CONCLUSION

The common gastric cancers are signet ring cell adenocarcinoma and intestinal type adenocarcinoma, affecting a wide range of age groups (33-91 years), with those over 60 years at greater risk. Interestingly, low Ki67 is associated with a higher mortality rate, whereas p53 has no prognostic significance. Expression of both Ki67 and p53 showed no association with survival time.

Erlotinib-containing benzenesulfonamides as anti-Helicobacter pylori agents through carbonic anhydrase inhibition

Aim: Development of dual-acting antibacterial agents containing Erlotinib, a recognized EGFR inhibitor used as an anticancer agent, with differently spaced benzenesulfonamide moieties known to bind and inhibit Helicobacter pylori carbonic anhydrase (HpCA) or the antiviral Zidovudine. Methods & materials: Through rational design, ten derivatives were obtained via a straightforward synthesis including a click chemistry reaction. Inhibitory activity against a panel of pathogenic carbonic anhydrases and antibacterial susceptibility of H. pylori ATCC 43504 were assessed. Docking studies on α-carbonic anhydrase enzymes and EGFR were conducted to gain insight into the binding mode of these compounds. Results & conclusion: Some compounds proved to be strong inhibitors of HpCA and showed good anti-H. pylori activity. Computational studies on the targeted enzymes shed light on the interaction hotspots.

New insights into the Lck-NF-κB signaling pathway

Lck is essential for the development, activity, and proliferation of T cells, which may contribute to pathological progression and development of human diseases, such as autoimmune disorders and cancers when functioning aberrantly. Nuclear factor-κB (NF-κB) was initially discovered as a factor bound to the κ light-chain immunoglobulin enhancer in the nuclei of activated B lymphocytes. Activation of the nuclear factor-κB pathway controls expression of several genes that are related to cell survival, apoptosis, and inflammation. Abnormal expression of Lck and nuclear factor-κB has been found in autoimmune diseases and malignancies, including rheumatoid arthritis, systemic lupus erythematosus, acute T cell lymphocytic leukemia, and human chronic lymphocytic leukemia, etc. Nuclear factor-κB inhibition is effective against autoimmune diseases and malignancies through blocking inflammatory responses, although it may lead to serious adverse reactions that are unexpected and unwanted. Further investigation of the biochemical and functional interactions between nuclear factor-κB and other signaling pathways may be helpful to prevent side-effects. This review aims to clarify the Lck-nuclear factor-κB signaling pathway, and provide a basis for identification of new targets and therapeutic approaches against autoimmune diseases and malignancies.

Cortactin: A universal host cytoskeletal target of Gram-negative and Gram-positive bacterial pathogens

Pathogenic bacteria possess a great potential of causing infectious diseases and represent a serious threat to human and animal health. Understanding the molecular basis of infection development can provide new valuable strategies for disease prevention and better control. In host-pathogen interactions, actin-cytoskeletal dynamics play a crucial role in the successful adherence, invasion, and intracellular motility of many intruding microbial pathogens. Cortactin, a major cellular factor that promotes actin polymerization and other functions, appears as a central regulator of host-pathogen interactions and different human diseases including cancer development. Various important microbes have been reported to hijack cortactin signaling during infection. The primary regulation of cortactin appears to proceed via serine and/or tyrosine phosphorylation events by upstream kinases, acetylation, and interaction with various other host proteins, including the Arp2/3 complex, filamentous actin, the actin nucleation promoting factor N-WASP, focal adhesion kinase FAK, the large GTPase dynamin-2, the guanine nucleotide exchange factor Vav2, and the actin-stabilizing protein CD2AP. Given that many signaling factors can affect cortactin activities, several microbes target certain unique pathways, while also sharing some common features. Here we review our current knowledge of the hallmarks of cortactin as a major target for eminent Gram-negative and Gram-positive bacterial pathogens in humans.

Investigating the Active Substance and Mechanism of San-Jiu-Wei-Tai Granules via UPLC-QE-Orbitrap-MS and Network Pharmacology

San-Jiu-Wei-Tai granules (SJWTG) are a significant Chinese patent medicine for the treatment of chronic gastritis (CG), having outstanding advantages in long-term treatment; however, the chemical composition and potential mechanism have not been investigated until now. In this study, a rapid separation and identification method based on UPLC-QE-Orbitrap-MS was established, and 95 chemical components from SJWTGs were identified, including 6 chemical components of an unknown source that are not derived from the 8 herbs included in SJWTGs. The identified chemical components were subsequently analysed by network pharmacology, suggesting that the core targets for the treatment of CG with SJWTGs were EGFR, SRC, AKT1, HSP90AA1, MAPK1, and MAPK3 and thus indicating that SJWTGs could reduce the inflammatory response of gastric epithelial cells and prevent persistent chronic inflammation that induces cancerization by regulating the MAPK signalling pathway and the C-type lectin receptor signalling pathway as well as their upstream and downstream pathways in the treatment of CG. The key bioactive components in SJWTGs were identified as 2,6-bis(4-ethylphenyl)perhydro-1,3,5,7-tetraoxanaphth-4-ylethane-1,2-diol, a chemical component of an unknown source, murrangatin, meranzin hydrate, paeoniflorin, and albiflorin. The results of molecular docking showed the strong binding interaction between the key bioactive components and the core targets, demonstrating that the key bioactive components deserve to be further studied and considered as Q-markers. By acting on multiple targets, SJWTG is less susceptible to drug resistance during the long-term treatment of CG, indicating the advantage of Chinese patent medicines. Furthermore, the preventive effect of SJWTGs on gastric cancer also demonstrates the superiority of preventive treatment of disease with traditional Chinese medicine.

Incorporating Immunotherapy in the Management of Gastric Cancer: Molecular and Clinical Implications

Simple Summary

Gastric cancer is one of the most common malignant tumours worldwide, with the fifth and third highest morbidity and mortality, respectively, of all cancers. Survival is limited, as most of the patients are diagnosed at an advanced stage, and are not suitable for surgery with a curative intent. Chemotherapy has only modestly improved patients’ outcomes and is mainly given with a palliative intent. Immunotherapy has improved overall survival of patients with gastric cancer, and has thus become a new standard of care in clinic. In this review we discuss the strong molecular rationale for the administration of immunotherapy in this disease and analyse the clinical data supporting its use.

Abstract

Gastric cancer has a median survival of 11 months, and this poor prognosis has not improved over the last 30 years. Recent pre-clinical data suggest that there is high tumour-related neoantigen expression in gastric cancer cells, suggesting that a clinical strategy that enhances the host’s immune system against cancer cells may be a successful approach to improve clinical outcomes. Additionally, there has been an increasing amount of translational evidence highlighting the relevance of PD-L1 expression in gastric cancer cells, indicating that PD-1/PD-L1 inhibitors may be useful. Several molecular subgroups of gastric cancer have been identified to respond with excellent outcomes to immunotherapy, including microsatellite instable tumours, tumours bearing a high tumour mutational burden, and tumours related to a chronic EBV infection. In gastric cancer, immunotherapy has produced durable responses in chemo-refractory patients; however, most recently there has been a lot of enthusiasm as several large-scale clinical trials highlight the improved survival noted from the incorporation of immunotherapy in the first line setting for advanced gastric cancer. Our review aims to discuss current pre-clinical and clinical data supporting the innovative role of immunotherapy in gastric cancer.

Manpixiao Decoction Halted the Malignant Transformation of Precancerous Lesions of Gastric Cancer: From Network Prediction to In-Vivo Verification

Manpixiao decoction (MPX), a traditional Chinese medicine formula, is mainly used to improve the gastric mucosal pathology and stomach discomfort in patients with gastric precancerous lesions. Precancerous lesion of gastric cancer (PLGC) refers to intestinal metaplasia and/or dysplasia based on gastric mucosal atrophy. Effective prevention and treatment of PLGC is of great significance to reduce the incidence of gastric cancer. Because of the complexity of the etiology and pathogenesis of PLGC, there is no unified and effective treatment plan in western medicine. In recent years, traditional Chinese medicine has shown obvious advantages in the treatment of PLGC and the prevention of its further progression to gastric cancer, relying on its multi-approach and multi-target comprehensive intervention characteristics. This study is designed to examine the protective effect of MPX against PLGC and further to reveal the engaged mechanism via integrating network pharmacology and in vivo experimental evidence. Network pharmacology results demonstrated that inflammation, immune responses, and angiogenesis might be associated with the efficacy of MPX in the treatment of PLGC, in which the PI3K-Akt, cellular senescence, P53 and protein processing in endoplasmic reticulum were involved. Then, we established a rat model of PLGC using a combination of N-methyl-N′-nitro-N-nitrosoguanidine (MNNG), sodium salicylate, irregular fasting, and ranitidine, and observed the effects after MPX treatment. Our result showed that MPX improved the pathological condition of gastric mucosa in PLGC rats and reduced the incidence of gastric cancer. Next, the analysis of serum inflammatory cytokines showed that MPX reduced the inflammation-related cytokines (such as IL-1α, IL-7, CSF-1, and CSF-3) in the serum. Additionally, MPX also had a regulation effect on the “protein/protein phosphorylation-signaling pathway” network in the core region of the PLGC rats. It is showed that MPX can inhibit the phosphorylation of PI3K-AKT, and downregulates the EGFR, β-catenin, and N-cadherin protein levels. These results indicate that MPX halted the PLGC progression through inhibiting EGFR-PI3K-AKT related epithelial-mesenchymal transition process.

Helicobacter pylori-Mediated Oxidative Stress and Gastric Diseases: A Review

Gastric cancer is considered to be a type of gastrointestinal tumor and is mostly accompanied by Helicobacter pylori (HP) infection at the early stage. Hence, the long-term colonization of the gastric mucosa by HP as a causative factor for gastrointestinal diseases cannot be ignored. The virulence factors secreted by the bacterium activate the signaling pathway of oxidative stress and mediate chronic inflammatory response in the host cells. The virulence factors also thwart the antibacterial effect of neutrophils. Subsequently, DNA methylation is induced, which causes continuous cell proliferation and evolution toward low-grade-differentiated gastric cells. This process provides the pathological basis for the occurrence of progressive gastric cancer. Therefore, this review aims to summarize the oxidative stress response triggered by HP in the gastric mucosa and the subsequent signaling pathways. The findings are expected to help in the formulation of new targeted drugs for preventing the occurrence of early gastric cancer and its progression to middle and advanced cancer.

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.

In vitro anti-bacterial activity and network pharmacology analysis of Sanguisorba officinalis L. against Helicobacter pylori infection

Background

Helicobacter pylori (H. pylori) infection has become an international public health problem, and antibiotic-based triple or quadruple therapy is currently the mainstay of treatment. However, the effectiveness of these therapies decreases due to resistance to multiple commonly used antibiotics. Sanguisorba officinalis L. (S. officinalis), a traditional Chinese medicine clinically used for hemostasis and treatment of diarrhea, has various pharmacological activities. In this study, in vitro antimicrobial activity was used for the preliminary evaluation of S. officinalis against H. pylori. And a pharmacology analysis approach was also utilized to elucidate its underlying mechanisms against H. pylori infection.

Methods

Micro-broth dilution method, agar dilution method, checkerboard assay, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used for the assessment of anti-bacterial activity. Active ingredients screening, GO analysis, KEGG analysis, construction of PPI network, molecular docking, and RT-qPCR were used to elucidate the underlying pharmacological mechanisms of S. officinalis against H. pylori infection.

Results

The minimum inhibitory concentration (MIC) values of S. officinalis against multiple H. pylori strains including clinically isolated multi-drug resistant (MDR) strains were ranging from 160 to 320 µg/ml. These results showed that S. officinalis had additive interaction with four commonly used antibiotics and could exert antibacterial effect by changing the morphology of bacteria without developing drug resistance. Through network pharmacology analysis, 8 active ingredients in S. officinalis were screened out for subsequent studies. Among 222 putative targets of S. officinalis, 49 targets were identified as potential targets for treatment of H. pylori infection. And these 49 targets were significantly enriched in GO processes such as protein kinase B signaling, protein kinase activity, protein kinase binding, and KEGG pathways such as Pathways in cancer, MicroRNAs in cancer, and TNF signaling pathway. Protein-protein interaction analysis yielded 5 core targets (AKT1, VEGFA, EGFR, SRC, CCND1), which were validated by molecular docking and RT-qPCR.

Conclusions

Overall, this study confirmed the in vitro inhibitory activity of S. officinalis against H. pylori and explored the possible pharmacological mechanisms, laying the foundation for further research and clinical application.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13020-021-00442-1.

Helicobacter pylori-Mediated Immunity and Signaling Transduction in Gastric Cancer

Helicobacter pylori infection is a leading cause of gastric cancer, which is the second-most common cancer-related death in the world. The chronic inflammatory environment in the gastric mucosal epithelia during H. pylori infection stimulates intracellular signaling pathways, namely inflammatory signals, which may lead to the promotion and progression of cancer cells. We herein report two important signal transduction pathways, the LPS-TLR4 and CagA-MET pathways. Upon H. pylori stimulation, lipopolysaccharide (LPS) binds to toll-like receptor 4 (TLR4) mainly on macrophages and gastric epithelial cells. This induces an inflammatory response in the gastric epithelia to upregulate transcription factors, such as NF-κB, AP-1, and IRFs, all of which contribute to the initiation and progression of gastric cancer cells. Compared with other bacterial LPSs, H. pylori LPS has a unique function of inhibiting the mononuclear cell (MNC)-based production of IL-12 and IFN-γ. While this mechanism reduces the degree of inflammatory reaction of immune cells, it also promotes the survival of gastric cancer cells. The HGF/SF-MET signaling plays a major role in promoting cellular proliferation, motility, migration, survival, and angiogenesis, all of which are essential factors for cancer progression. H. pylori infection may facilitate MET downstream signaling in gastric cancer cells through its CagA protein via phosphorylation-dependent and/or phosphorylation-independent pathways. Other signaling pathways involved in H. pylori infection include EGFR, FAK, and Wnt/β-Catenin. These pathways function in the inflammatory process of gastric epithelial mucosa, as well as the progression of gastric cancer cells. Thus, H. pylori infection-mediated chronic inflammation plays an important role in the development and progression of gastric cancer.

Pathways of Gastric Carcinogenesis, Helicobacter pylori Virulence and Interactions with Antioxidant Systems, Vitamin C and Phytochemicals

Helicobacter pylori is a class one carcinogen which causes chronic atrophic gastritis, gastric intestinal metaplasia, dysplasia and adenocarcinoma. The mechanisms by which H. pylori interacts with other risk and protective factors, particularly vitamin C in gastric carcinogenesis are complex. Gastric carcinogenesis includes metabolic, environmental, epigenetic, genomic, infective, inflammatory and oncogenic pathways. The molecular classification of gastric cancer subtypes has revolutionized the understanding of gastric carcinogenesis. This includes the tumour microenvironment, germline mutations, and the role of Helicobacter pylori bacteria, Epstein Barr virus and epigenetics in somatic mutations. There is evidence that ascorbic acid, phytochemicals and endogenous antioxidant systems can modify the risk of gastric cancer. Gastric juice ascorbate levels depend on dietary intake of ascorbic acid but can also be decreased by H. pylori infection, H. pylori CagA secretion, tobacco smoking, achlorhydria and chronic atrophic gastritis. Ascorbic acid may be protective against gastric cancer by its antioxidant effect in gastric cytoprotection, regenerating active vitamin E and glutathione, inhibiting endogenous N-nitrosation, reducing toxic effects of ingested nitrosodimethylamines and heterocyclic amines, and preventing H. pylori infection. The effectiveness of such cytoprotection is related to H. pylori strain virulence, particularly CagA expression. The role of vitamin C in epigenetic reprogramming in gastric cancer is still evolving. Other factors in conjunction with vitamin C also play a role in gastric carcinogenesis. Eradication of H. pylori may lead to recovery of vitamin C secretion by gastric epithelium and enable regression of premalignant gastric lesions, thereby interrupting the Correa cascade of gastric carcinogenesis.