Expression of caspase-3 predicts prognosis in advanced noncardia gastric cancer

The intersection between cysteine proteases, Ca2+ signalling and cancer cell apoptosis

Apoptosis is a highly complex and regulated cell death pathway that safeguards the physiological balance between life and death. Over the past decade, the role of Ca2+ signalling in apoptosis and the mechanisms involved have become clearer. The initiation and execution of apoptosis is coordinated by three distinct groups of cysteines proteases: the caspase, calpain and cathepsin families. Beyond its physiological importance, the ability to evade apoptosis is a prominent hallmark of cancer cells. In this review, we will explore the involvement of Ca2+ in the regulation of caspase, calpain and cathepsin activity, and how the actions of these cysteine proteases alter intracellular Ca2+ handling during apoptosis. We will also explore how apoptosis resistance can be achieved in cancer cells through deregulation of cysteine proteases and remodelling of the Ca2+ signalling toolkit.

Uncovering the potential role of oxidative stress in the development of periodontitis and establishing a stable diagnostic model via combining single-cell and machine learning analysis

BACKGROUND

The primary pathogenic cause of tooth loss in adults is periodontitis, although few reliable diagnostic methods are available in the early stages. One pathological factor that defines periodontitis pathology has previously been believed to be the equilibrium between inflammatory defense mechanisms and oxidative stress. Therefore, it is necessary to construct a model of oxidative stress-related periodontitis diagnostic markers through machine learning and bioinformatic analysis.

METHODS

We used LASSO, SVM-RFE, and Random Forest techniques to screen for periodontitis-related oxidative stress variables and construct a diagnostic model by logistic regression, followed by a biological approach to build a Protein-Protein interaction network (PPI) based on modelled genes while using modelled genes. Unsupervised clustering analysis was performed to screen for oxidative stress subtypes of periodontitis. we used WGCNA to explore the pathways correlated with oxidative stress in periodontitis patients. Networks. Finally, we used single-cell data to screen the cellular subpopulations with the highest correlation by scoring oxidative stress genes and performed a proposed temporal analysis of the subpopulations.

RESULTS

We discovered 3 periodontitis-associated genes (CASP3, IL-1β, and TXN). A characteristic line graph based on these genes can be helpful for patients. The primary hub gene screened by the PPI was constructed, where immune-related and cellular metabolism-related pathways were significantly enriched. Consistent clustering analysis found two oxidative stress categories, with the C2 subtype showing higher immune cell infiltration and immune function ratings. Therefore, we hypothesized that the high expression of oxidative stress genes was correlated with the formation of the immune environment in patients with periodontitis. Using the WGCNA approach, we examined the co-expressed gene modules related to the various subtypes of oxidative stress. Finally, we selected monocytes for mimetic time series analysis and analyzed the expression changes of oxidative stress genes with the mimetic time series axis, in which the expression of JUN, TXN, and IL-1β differed with the change of cell status.

CONCLUSION

This study identifies a diagnostic model of 3-OSRGs from which patients can benefit and explores the importance of oxidative stress genes in building an immune environment in patients with periodontitis.

Network pharmacology-based screening of the active ingredients and mechanisms of evodiae fructus anti-glioblastoma multiforme

BACKGROUND

Evodiae fructus has been shown to have anti-glioblastoma multiforme (GBM) effects. However, its anti-GBM active components and mechanism remain unclear. In this study, the active components of evodiae fructus were screened by network pharmacology to explore the possible molecular mechanism of resistance to GBM.

MATERIALS AND METHODS

The main active ingredients of evodiae fructus were derived from Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) and Batch-traditional Chinese medicine (TCM). TCMSP and Swiss absorption, distribution, metabolism and elimination (ADME) predict genetic targets for ingredients that meet pharmacological criteria. GBM-related targets were obtained from DisGeNet, GeneCards, Online Mendelian Inheritance in Man (OMIM), Therapeutic Target Database (TTD), and TCGA. A Venn diagram was used to obtain the common targets of evodiae fructus and GBM. Protein-protein interaction (PPI) networks and component-disease target networks were constructed using Cytoscape 3.8.1 software for visualization. GBM gene differential expression was visualized by VolcaNoseR, and potential targets were enriched by Gene Ontology (GO) function and annotated by the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway by SRplot. Molecular docking verification was conducted using AutoDock Vina software.

RESULTS

According to the screening conditions, 24 active components and 80 drug targets were obtained. The PPI network contains 80 proteins. The molecular docking verification showed the molecular docking affinity of the core active compounds in evodiae fructus with CASP3, JUN, EGFR, and AKT1.

CONCLUSIONS

This study preliminarily identified the various molecular targets and multiple pathways of evodiae fructus against GBM.

Targeting inhibitor of apoptosis proteins (IAPs) with IAP inhibitors sensitises malignant rhabdoid tumour cells to cisplatin

Malignant rhabdoid tumour (MRT) is a rare, aggressive paediatric malignancy most commonly diagnosed in those below the age of three. MRTs can arise in soft tissue but are more often associated with the central nervous system or kidney. Unfortunately, the prognosis upon diagnosis with MRT is poor. Given the resistance of MRT to current treatment protocols including cisplatin, and the vulnerability of this young patient population to aggressive therapies, there is a need for novel treatment options. Several members of the inhibitor of apoptosis protein (IAP) family including X‑linked inhibitor of apoptosis (XIAP), cellular inhibitor of apoptosis proteins 1 and 2 (cIAP1/cIAP2), livin and survivin have been implicated in chemotherapy resistance in various malignancies. We have previously demonstrated expression of these IAP family members in a panel of MRT cell lines. In the present study, sensitivity of this same panel of MRT cell lines to small-molecule mediated inhibition of the IAPs via the survivin inhibitor YM155 and the XIAP/cIAP1/cIAP2 inhibitor BV6 was demonstrated. Additionally, both BV6 and the XIAP inhibitor embelin synergistically enhanced cisplatin mediated apoptotic cell death in MRT cell lines, with enhanced caspase-3 cleavage. Importantly, we have demonstrated, for the first time, expression of XIAP, its target caspase-3 and its endogenous inhibitor SMAC in rhabdoid tumour patient tissue. In conclusion, this study provides pre-clinical evidence that IAP inhibition may be a new therapeutic option in MRT.

Combination of berberine and low glucose inhibits gastric cancer through the PP2A/GSK3β/MCL-1 signaling pathway

Intermittent fasting as an adjuvant therapy in clinical practice is an emerging treatment modality to target tumor growth by reducing glucose utilization. Berberine, an alkaloid extracted from the traditional Chinese medicine Coptidis Rhizoma, has been shown to be a safe and effective antitumor agent in several cancers. Hence, the purpose of the present study was to investigate the effects of the combination of berberine and low glucose on gastric cancer. Our results showed that the combination of berberine and low glucose effectively inhibited cell viability, promoted apoptosis, and reduced the migration ability of MGC803 cells. In addition, the combination was shown to activate the PP2A/GSK3β signaling axis, leading to the downregulation of the downstream pro-survival protein MCL-1, which leads to the death of gastric cancer cells. In addition, the inhibitor of GSK3β partially reversed the effect of this combination on MGC803 cells. In vivo experiments demonstrated that berberine effectively impaired the growth of xenograft tumors, when administered during intermittent fasting (hypoglycemic conditions), and was well tolerated by nude mice without the occurrence of any adverse effects. Based on these results, we conclude that the berberine/low-glucose combination can inhibit the growth of gastric cancer through the PP2A/GSK3β/MCL-1 signaling pathway. Accordingly, this combination of drugs and lifestyle may become a new type of safe and effective anti-cancer therapy.

The potential of proliferative and apoptotic parameters in clinical flow cytometry of myeloid malignancies

Standardization of the detection and quantification of leukocyte differentiation markers by the EuroFlow Consortium has led to a major step forward in the integration of flow cytometry into classification of leukemia and lymphoma. In our opinion, this now enables introduction of markers for more dynamic parameters, such as proliferative and (anti)apoptotic markers, which have proven their value in the field of histopathology in the diagnostic process of solid tumors and lymphoma. Although use of proliferative and (anti)apoptotic markers as objective parameters in the diagnostic process of myeloid malignancies was studied in the past decades, this did not result in the incorporation of these biomarkers into clinical diagnosis. This review addresses the potential of these markers for implementation in the current, state-of-the-art multiparameter analysis of myeloid malignancies. The reviewed studies clearly recognize the importance of proliferation and apoptotic mechanisms in the pathogenesis of bone marrow (BM) malignancies. The literature is, however, contradictory on the role of these processes in myelodysplastic syndrome (MDS), MDS/myeloproliferative neoplasms, and acute myeloid leukemia. Furthermore, several studies underline the need for the analysis of the proliferative and apoptotic rates in subsets of hematopoietic BM cell lineages and argue that these results can have diagnostic and prognostic value in patients with myeloid malignancies. Recent developments in multiparameter flow cytometry now allow quantification of proliferative and (anti)apoptotic indicators in myeloid cells during their different maturation stages of separate hematopoietic cell lineages. This will lead to a better understanding of the biology and pathogenesis of these malignancies.

Anakoinosis: Correcting Aberrant Homeostasis of Cancer Tissue-Going Beyond Apoptosis Induction

The current approach to systemic therapy for metastatic cancer is aimed predominantly at inducing apoptosis of cancer cells by blocking tumor-promoting signaling pathways or by eradicating cell compartments within the tumor. In contrast, a systems view of therapy primarily considers the communication protocols that exist at multiple levels within the tumor complex, and the role of key regulators of such systems. Such regulators may have far-reaching influence on tumor response to therapy and therefore patient survival. This implies that neoplasia may be considered as a cell non-autonomous disease. The multi-scale activity ranges from intra-tumor cell compartments, to the tumor, to the tumor-harboring organ to the organism. In contrast to molecularly targeted therapies, a systems approach that identifies the complex communications networks driving tumor growth offers the prospect of disrupting or "normalizing" such aberrant communicative behaviors and therefore attenuating tumor growth. Communicative reprogramming, a treatment strategy referred to as anakoinosis, requires novel therapeutic instruments, so-called master modifiers to deliver concerted tumor growth-attenuating action. The diversity of biological outcomes following pro-anakoinotic tumor therapy, such as differentiation, trans-differentiation, control of tumor-associated inflammation, etc. demonstrates that long-term tumor control may occur in multiple forms, inducing even continuous complete remission. Accordingly, pro-anakoinotic therapies dramatically extend the repertoire for achieving tumor control and may activate apoptosis pathways for controlling resistant metastatic tumor disease and hematologic neoplasia.

A Systems Pharmacology Approach for Identifying the Multiple Mechanisms of Action of the Wei Pi Xiao Decoction for the Treatment of Gastric Precancerous Lesions

The Wei Pi Xiao (WPX) decoction, based on the theory of traditional Chinese medicine, has been widely used for the treatment of gastric precancerous lesions (GPL). Although WPX is known to be effective for the treatment of GPL, its active ingredients, cellular targets, and the precise molecular mechanism of action are not known. This study aimed to identify the multiple mechanisms of action of the WPX decoction in the treatment of GPL. The active compounds, drug targets, and the key pathways involved in the therapeutic effect of WPX in the treatment of GPL were analyzed by an integrative analysis pipeline. The information pertaining to the compounds present in WPX and their disease targets was obtained from TCMSP and GeneCards, respectively. The mechanisms underlying the therapeutic effect of WPX were investigated with gene ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. A total of 82 bioactive compounds and 146 related targets were identified in this study. Following target analyses, the targets were further mapped to 26 key biological processes and 21 related pathways to construct a target-pathway network and an integrated GPL pathway. The study demonstrated that the WPX formula primarily treats the dysfunctions of GPL arising from cell proliferation, apoptosis, and mucosal inflammation, which offered a novel insight into the pathogenesis of GPL and revealed the molecular mechanism underlying the therapeutic effects of the WPX formula in GPL. This study offers a novel approach for the systematic investigation of the mechanisms of action of herbal medicines, which will provide an impetus to the GPL drug development pipeline.

Lowering Etoposide Doses Shifts Cell Demise From Caspase-Dependent to Differentiation and Caspase-3-Independent Apoptosis via DNA Damage Response, Inducing AML Culture Extinction

Cytotoxic chemotherapy, still the most widely adopted anticancer treatment, aims at eliminating cancer cells inducing apoptosis with DNA damaging agents, exploiting the differential replication rate of cancer vs. normal cells; efficiency is evaluated in terms of extent of induced apoptosis, which depends on the individual cell sensitivity to a given drug, and on the dose. In this in vitro study, we report that the concentration of etoposide, a topoisomerase II poison widely used in clinics, determines both the kinetics of cell death, and the type of apoptosis induced. We observed that on a set of myeloid leukemia cell lines, etoposide at high (50 uM) dose promoted a rapid caspase-3-mediated apoptosis, whereas at low (0.5 uM) dose, it induced morphological and functional granulocytic differentiation and caspase-2-dependent, but caspase-3-independent, cell death, displaying features consistent with apoptosis. Both differentiation and caspase-2- (but not 3)-mediated apoptosis were contrasted by caffeine, a well-known inhibitor of the cellular DNA damage response (DDR), which maintained cell viability and cycling, indicating that the effects of low etoposide dose are not the immediate consequence of damage, but the result of a signaling pathway. DDR may be thus the mediator responsible for translating a mere dosage-effect into different signal transduction pathways, highlighting a strategic action in regulating timing and mode of cell death according to the severity of induced damage. The evidence of different molecular pathways induced by high vs. low drug doses may possibly contribute to explain the different effects of cytotoxic vs. metronomic therapy, the latter achieving durable clinical responses by treating cancer patients with stable, low doses of otherwise canonical cytotoxic drugs; intriguingly caspase-3, a major promoter of wounded tissue regeneration, is also a key factor of post-therapy cancer repopulation. All this suggests that cancer control in response to cytotoxic drugs arises from complex reprogramming mechanisms in tumor tissue, recently described as anakoinosis.

An apoptosis-driven 'onco-regenerative niche': roles of tumour-associated macrophages and extracellular vesicles

The cell-death programme, apoptosis, is well established as a tumour suppressor mechanism. Paradoxically, high levels of apoptosis in tumours are closely coupled with poor prognosis. Indeed, where it has been studied, cell loss is a striking feature of high-grade cancers, illustrating the importance of considering malignant disease as an imbalance between cell gain and cell loss that favours cell gain rather than as a unidirectional disorder of cell gain alone. In addition to orchestrating cell loss, apoptosis can signal regenerative responses—for example compensatory proliferation—in neighbouring cells. Accumulating evidence suggests that normal tissue repair and regenerative processes are hijacked in the malignant tissue microenvironment such that cancer may be likened to a ‘wound that fails to stop repairing’. We have proposed that a critical requirement for the successful growth, progression and re-growth of malignant tumours is a complex milieu, conceptually termed the ‘onco-regenerative niche’, which is composed, in addition to transformed neoplastic cells, of a network of normal cells and factors activated as if in tissue repair and regeneration. Our work is based around the hypothesis that tumour cell apoptosis, macrophage activation and endothelial activation are key, interlinked elements of the onco-regenerative niche and that apoptotic tumour cell–derived extracellular vesicles provide critical intercellular communication vehicles of the niche. In aggressive B-cell lymphoma, tumour cell apoptosis promotes both angiogenesis and the accumulation of pro-tumour macrophages in the lymphoma microenvironment. Furthermore, apoptotic lymphoma-derived extracellular vesicles have potent pro-tumour potential. These findings have important implications for the roles of apoptosis in regulation of malignant diseases and for the efficacy of apoptosis-inducing anti-cancer therapies.

This article is part of the discussion meeting issue ‘Extracellular vesicles and the tumour microenvironment’.

Anti-cancer activity and potential mechanism of a novel aspirin derivative

Aspirin has been used in the treatment and chemoprevention of many malignant cancers. The mechanism of its anti-cancer activity mainly involves the inhibition of cyclooxygenase-2 (COX-2). However, the application of aspirin is limited by the serious gastric mucosal damage that accompanies its usage. We have previously reported the preparation of a novel aspirin derivative that we named Ca-Asp, and showed that it causes less damage to gastric mucosa of rat and inhibits the expression of COX-2 to higher degree than Asp. However, the anti-cancer effect and mechanism of Ca-Asp was not demonstrated. In this study, the anti-cancer effect of Ca-Asp was investigated and compared with those of Asp and Hydroxyapatite (Hap) at the cell level. The results showed that treatment of SGC-7901 cells (human gastric cancer cell line) with 200-400μg/ml Ca-Asp resulted in significant reduction in cell viability, compared to treatment with either Asp or Hap, and at a higher concentration (500μg/ml). Subsequent investigation into the possible underlying mechanism showed that Ca-Asp induced apoptosis and caused cell cycle arrest at the G1 phase. Ca-Asp also up-regulated the levels of caspase-3 and p53, but down regulated the level of cyclin D1, NF-κB, COX-2 and PGE₂. Furthermore, simultaneous treatment of SGC-7901 cells with Ca-Asp and exogenous PGE₂ reduced the anti-proliferative effect of Ca-Asp on the cells. Taken together, the results suggested that Ca-Asp might act as a potential anti-cancer drug, and that its suppression of PGE₂ production might constitute an important part of its anti-cancer activity.