Tomentosin induces apoptotic pathway by blocking inflammatory mediators via modulation of cell proteins in AGS gastric cancer cell line

GPR137 inactivates Hippo signaling to promote gastric cancer cell malignancy

As the fifth most common cancer in the world, gastric cancer (GC) ranks as the third major cause of cancer-related death globally. Although surgical resection and chemotherapy still remains the mainstay of potentially curative treatment for GC, chemotherapy resistance and adverse side effects limit their clinical applications. Thus, further investigation of the mechanisms of carcinogenesis in GC and discovery of novel biomarkers is of great concern. We herein report that the elevated expression of GPR137 is correlated with GC. Overexpression of GPR137 potentiates human gastric cancer AGS cell malignancy, including proliferation, migration, invasion, colony formation and xenograft growth in nude mice in vivo, whereas knockout of GPR137 by CRISPR/Cas9 gene editing exerts the opposite effects. Mechanistically, GPR137 could bind to MST, the upstream kinases in Hippo pathway, which disrupts the association of MST with LATS, subsequently activating the transcriptional co-activators, YAP and TAZ, and thereby triggering the target transcription and the alterations in GC cell biological actions consequently. Therefore, our findings may provide with the evidence of developing a potentially novel treatment method with specific target for GC.

Research progress on antitumor mechanisms and molecular targets of Inula sesquiterpene lactones

The pharmacological effects of natural product therapy have received sigificant attention, among which terpenoids such as sesquiterpene lactones stand out due to their biological activity and pharmacological potential as anti-tumor drugs. Inula sesquiterpene lactones are a kind of sesquiterpene lactones extracted from Inula species. They have many pharmacological activities such as anti-inflammation, anti-asthma, anti-tumor, neuroprotective and anti-allergic. In recent years, more and more studies have proved that they are important candidate drugs for the treatment of a variety of cancers because of its good anti-tumor activity. In this paper, the structure, structure-activity relationship, antitumor activities, mechanisms and targets of Inula sesquiterpene lactones reported in recent years were reviewed in order to provide clues for the development of novel anticancer drugs.

Unveiling the anti-glioma potential of a marine derivative, Fucoidan: its synergistic cytotoxicity with Temozolomide-an in vitro and in silico experimental study

Glioma coined as a "butterfly" tumor associated with a dismal prognosis. Marine algal compounds with the richest sources of bioactive components act as significant anti-tumor therapeutics. However, there is a paucity of studies conducted on Fucoidan to enhance the anti-glioma efficacy of Temozolomide. Therefore, the present study aimed to evaluate the synergistic anti-proliferative, anti-inflammatory and pro-apoptotic effects of Fucoidan with Temozolomide in in vitro and in silico experimental setup. The anti-proliferative effects of Temozolomide and Fucoidan were evaluated on C6 glioma cells by MTT and migration assay. Modulation of inflammatory markers and apoptosis induction was affirmed at the morphological and transcriptional level by dual staining and gene expression. Molecular docking (MD) and molecular dynamics simulation (MDS) studies were performed against the targets to rationalize the inhibitory effect. The dual-drug combination significantly reduced the cell viability and migration of glioma cells in a synergistic dose-dependent manner. At the molecular level, the dual-drug combination significantly down-regulated inflammatory genes with a concomitant upregulation of pro-apoptotic marker. In consensus with our in vitro findings, molecular docking and simulation studies revealed that the anti-tumor ligands: Temozolomide, Fucoidan with 5-(3-Methy1-trizeno)-imidazole-4-carboxamide (MTIC), and 4-amino-5-imidazole-carboxamide (AIC) had the potency to bind to the inflammatory proteins at their active sites, mediated by H-bonds and other non-covalent interactions. The dual-drug combinatorial treatment synergistically inhibited the proliferation, migration of glioma cells and promoted apoptosis; conversely with the down-regulation of inflammatory genes. However, pre-clinical experimental evidence is warranted for the possible translation of this combination.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-023-03814-6.

Traditional Chinese medicine for transformation of gastric precancerous lesions to gastric cancer: A critical review

Gastric cancer (GC) is a common gastrointestinal tumor. Gastric precancerous lesions (GPL) are the last pathological stage before normal gastric mucosa transforms into GC. However, preventing the transformation from GPL to GC remains a challenge. Traditional Chinese medicine (TCM) has been used to treat gastric disease for millennia. A series of TCM formulas and active compounds have shown therapeutic effects in both GC and GPL. This article reviews recent progress on the herbal drugs and pharmacological mechanisms of TCM in preventing the transformation from GPL to GC, especially focusing on anti-inflammatory, anti-angiogenesis, proliferation, and apoptosis. This review may provide a meaningful reference for the prevention of the transformation from GPL to GC using TCM.

Antineoplastic Properties by Proapoptotic Mechanisms Induction of Inula viscosa and Its Sesquiterpene Lactones Tomentosin and Inuviscolide

Cancer is a complex disease including approximately 200 different entities that can potentially affect all body tissues. Among the conventional treatments, radiotherapy and chemotherapy are most often applied to different types of cancers. Despite substantial advances in the development of innovative antineoplastic drugs, cancer remains one of the most significant causes of death, worldwide. The principal pitfall of successful cancer treatment is the intrinsic or acquired resistance to therapeutic agents. The development of more effective or synergistic therapeutic approaches to improve patient outcomes and minimize toxicity has become an urgent issue. Inula viscosa is widely distributed throughout Europe, Africa, and Asia. Used as a medicinal plant in different countries, I. viscosa has been characterized for its complex chemical composition in order to identify the bioactive compounds responsible for its biological activities, including anticancer effects. Sesquiterpene lactones (SLs) are natural, biologically active products that have attracted considerable attention due to their biological activities. SLs are alkylating agents that form covalent adducts with free cysteine residues within enzymes and key proteins favoring cancer cell cytotoxicity. They are effective inducers of apoptosis in several cancer cell types through different molecular mechanisms. This review focuses on recent advances in the cytotoxic effects of I. viscosa and SLs in the treatment of neoplastic diseases, with a special emphasis on their proapoptotic molecular mechanisms.

Tomentosin induces apoptosis in pancreatic cancer cells through increasing reactive oxygen species and decreasing mitochondrial membrane potential

The aim of this study was to determine possible anticancer effect of tomentosin, a natural sesquiterpene lactone, on pancreatic cancer cells. The cytotoxic effect of tomentosin was determined by XTT analysis. Colony formation and apoptosis analyzes were performed, Reactive oxygen species (ROS) level and change in mitochondrial membrane potential (MMP) were evaluated in control and tomentosin-treated cells. The effect of tomentosin on expression levels of apoptosis-related genes was determined by qRT-PCR and Caspase-3 and Caspase-9 proteins were analyzed by western blot. And, the effect of tomentosin on migration and invasion of cells were evaluated. The IC₅₀ dose of tomentosin was found to be 31.11 μM in PANC-1 cells and 33.93 μM in MIA PaCa-2 cells for 48 h. And, treatment of tomentosin at IC₅₀ dose suppressed the colony forming capacity of cells. While tomentosin increased apoptosis rate and ROS production, an decrease was observed in MMP. Tomentosin affected expression level of apoptosis-related genes and increased Caspase-3 and Caspase-9 protein levels. After tomentosin treatment, cell migration and invasion were suppressed. As a result, this study reveals that tomentosin has anticancer effects on pancreatic cancer cells, and therefore it predicts that tomentosin can be evaluated as an effective agent against pancreatic cancer.

Anti-Cancer Activity of Gedunin by Induction of Apoptosis in Human Gastric Cancer AGS Cells

Currently, gastric cancer is considered one of the major causes of high mortality and morbidity worldwide. Recent advances in therapeutics, clinical treatment, staging procedures, and imaging techniques are high, yet the prevalence of gastric cancer has not been reduced. Usage of the synthetic drug has many side effects that can lead to other ailments. Gedunin, a phytochemical derived from Azadirachta indica (neem tree), exhibits several pharmacological activities including antitumor, anti-inflammatory, antiulcer, antipyretics, antibacterial, antifungal, anti-diabetic, and antimalarial properties. In the current investigation, the effect of gedunin on the cell viability; reactive oxygen species (ROS) generation by DCFH-DA staining; mitochondrial membrane potential (MMP) by Rh-123 staining; apoptosis by AO/EtBr staining; cell migration and wound healing ability by wound scratch assay; and Bcl-2, Bax, caspase-3, and caspase-9 by ELISA techniques were analyzed in the AGS cells. The treatment with gedunin effectively inhibited the cell viability with IC₅₀ = 20µM, increased the ROS generation, and triggered the apoptosis in AGS cells. The gedunin-treated AGS cells also demonstrated a decreased MMP status. The increment in the ROS generation leads to oxidative stress which in turn induce the apoptosis. The activity of Bax gene was upregulated and the activity of Bcl-2 gene was down-regulated in the AGS cells after the treatment with gedunin. In the AGS cells treated with gedunin, the caspase-3 and caspase-9 activities were increased. In overall, these findings suggested that gedunin can be used as a potent chemotherapeutic agent in the future to treat gastric cancer.

A new specific method for isolation of tomentosin with a high yield from Inula viscosa (L.) and determination of its bioactivities

INTRODUCTION

Tomentosin, the characteristic component of Inula viscosa (L.) is an important sesquiterpene lactone with anticarcinogenic effects. Methods of obtaining pure tomentosin are not sufficient for anticancer drug research.

OBJECTIVES

This study aims to develop a specific method to isolate tomentosin from I. viscosa with high yield. It also aims to investigate the inhibitory effects of tomentosin on human carbonic anhydrase I (hCAI), human carbonic anhydrase II (hCAII), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α-glucosidase, and α-amylase enzymes.

MATERIAL AND METHODS

Tomentosin was purified by a specific column chromatography method. The content of tomentosin in dichloromethane, dichloromethane by Soxhlet method, ethanol and ethanol by Soxhlet method extracts of I. viscosa was determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Half maximal inhibitory concentration (IC₅₀ ) and inhibition constant (K_i ) values were calculated to determine in vitro enzyme inhibition effects.

RESULTS

Tomentosin was isolated in high yield (0.64%). The IC₅₀ and K_i values for tomentosin were calculated as 5.00 ± 0.19 (r = 0.9688) and 4.62 ± 0.10 μM for hCAI, 5.40 ± 0.26 (r = 0.9677) and 5.22 ± 0.31 μM for hCAII, 6.75 ± 0.208 (r = 0.9891) and 3.75 ± 0.27 μM for AChE, 6.67 ± 0.307 (r = 0.9820) and 0.51 ± 0.11 μM for BChE, 26.61 ± 0.236 (r = 0.9815) and 2.61 ± 0.71 μM for α-glucosidase and 26.89 ± 1.54 μM (r = 0.9670) for α-amylase, respectively.

CONCLUSION

Tomentosin was isolated in high yield from the paste-like extract of I. viscosa compared to the positive controls, it was determined that tomentosin was weakly effective against hCAI, hCAII, AChE and BChE, but thoroughly effective against α-glucosidase and α-amylase. These results suggested that tomentosin has α-glucosidase and α-amylase inhibitor potential.

Design, Synthesis, and Biological Evaluation of Novel Tomentosin Derivatives in NMDA-Induced Excitotoxicity

N-methyl-D-aspartate (NMDA) receptor stimulation may lead to excitotoxicity, which triggers neuronal death in brain disorders. In addition to current clinical therapeutic approaches, treatment strategies by phytochemicals or their derivatives are under investigation for neurodegenerative diseases. In the present study, novel amino and 1,2,3-triazole derivatives of tomentosin were prepared and tested for their protective and anti-apoptotic effects in NMDA-induced excitotoxicity. Amino-tomentosin derivatives were generated through a diastereoselective conjugate addition of several secondary amines to the α-methylene-γ-butyrolactone function, while the 1,2,3-triazolo-tomentosin was prepared by a regioselective Michael-type addition carried out in the presence of trimethylsilyl azide (TMSN3) and the α-methylene-γ-lactone function. The intermediate key thus obtained underwent 1,3-dipolar Huisgen cycloaddition using a wide range of terminal alkynes. The possible effects of the derivatives on cell viability and free-radical production following NMDA treatment were measured by Water-Soluble Tetrazolium Salts (WST-1) and Dichlorofluorescein Diacetate (DCF-DA) assays, respectively. The alterations in apoptosis-related proteins were examined by Western blot technique. Our study provides evidence that synthesized triazolo- and amino-tomentosin derivatives show neuroprotective effects by increasing cellular viability, decreasing ROS production, and increasing the Bcl-2/Bax ratio in NMDA-induced excitotoxicity. The findings highlight particularly 2e, 2g, and 6d as potential regulators and neuroprotective agents in NMDA overactivation.

The effects of ellagic acid and other pomegranate (Punica granatum L.) derivatives on human gastric cancer AGS cells

Although surgery with or without (neo)adjuvant chemo/radiotherapy, as the standard treatments, can be suitable therapeutic strategies for gastric cancer, side effects and drug resistance are two main treatment obstacles. It has been discovered that pomegranate and its natural derivatives, especially ellagic acid (EA), offer significant anti-cancer effects while causing trivial side effects. In this study, we aimed to explore the anti-cancer effects of EA on a human gastric adenocarcinoma cell line (AGS) as well as in immunocompromised mice bearing human gastric tumors, for the first time. HPLC was used for determining EA in samples. MTT assay, apoptosis and scratch assay, gelatin zymography, and quantitative RT-PCR were used to determine the anti-cancer properties of different concentrations of pomegranate fruit juice, pomegranate peel extract, and EA. Furthermore, the effects of these compounds were investigated on immunosuppressed C57BL/6 mice carrying human gastric cancer tumors. EA could inhibit the proliferation and migration of gastric cancer cells. It also had significant effects on reducing both expression and activity of MMP-2 and MMP-9. Further, it was demonstrated that with alterations in the expression of genes involved in apoptosis and inflammation including P53, BAX, APAF1, BCL2, iNOS, NF-κB, IL-8, and TNF-α, EA treatment led to increased cancer cell death and reduced inflammation. Furthermore, its use in mice bearing gastric tumors resulted in a significant reduction in tumor volume without any obvious side effects. Ellagic acid exhibited anti-cancer effects on gastric adenocarcinoma, and can be considered as a safe anti-cancer agent for further preclinical studies on this cancer.

Targeting mitochondria as a therapeutic anti-gastric cancer approach

Gastric cancer is regarded as the fifth most common cancer globally but the third most common cancer death. Although systemic chemotherapy is the primary treatment for advanced gastric cancer patients, the outcome of chemotherapy is unsatisfactory. Novel therapeutic strategies and potential alternative treatments are therefore needed to overcome the impact of this disease. At a cellular level, mitochondria play an important role in cell survival and apoptosis. A growing body of studies have shown that mitochondria play a central role in the regulation of cellular function, metabolism, and cell death during carcinogenesis. Interestingly, the impact of mitochondrial dynamics, including fission/fusion and mitophagy, on carcinogenesis and cancer progression has also been reported, suggesting the potential targeting of mitochondrial dynamics for the treatment of cancer. This review not only comprehensively summarizes the homeostasis of gastric cancer cells, but the potential therapeutic interventions for the targeting of mitochondria for gastric cancer therapy are also highlighted and discussed.

Anticancer and Anti-Inflammatory Effects of Tomentosin: Cellular and Molecular Mechanisms

Tomentosin is a natural compound known for its presence in some medicinal plants of the Asteraceae family such as Inula viscosa. Recent studies have highlighted its anticancer and anti-inflammatory properties. Its anticancer mechanisms are unique and act at different levels ranging from cellular organization to molecular transcriptional factors and epigenetic modifications. Tomentosin’s possession of the modulatory effect on telomerase expression on tumor cell lines has captured the interest of researchers and spurred a more robust study on its anticancer effect. Since inflammation has a close link with cancer disease, this natural compound appears to be a potential cancer-fighting drug. Indeed, its recently demonstrated anti-inflammatory action can be considered as a starting point for its evaluation as an anticancer chemo-preventive agent

Tomentosin a Sesquiterpene Lactone Induces Antiproliferative and Proapoptotic Effects in Human Burkitt Lymphoma by Deregulation of Anti- and Pro-Apoptotic Genes

(1) Tomentosin is the most representative sesquiterpene lactone extracted by I. viscosa. Recently, it has gained particular attention in therapeutic oncologic fields due to its anti-tumor properties. (2) In this study, the potential anticancer features of tomentosin were evaluated on human Burkitt’s lymphoma (BL) cell line, treated with increasing tomentosin concentration for cytotoxicity screening. (3) Our data showed that both cell cycle arrest and cell apoptosis induction are responsible of the antiproliferative effects of tomentosin and may end in the inhibition of BL cell viability. Moreover, a microarray gene expression profile was performed to assess differentially expressed genes contributing to tomentosin activity. Seventy-five genes deregulated by tomentosin have been identified. Downregulated genes are enriched in immune-system pathways, and PI3K/AKT and JAK/STAT pathways which favor proliferation and growth processes. Importantly, different deregulated genes identified in tomentosin-treated BL cells are prevalent in molecular pathways known to lead to cellular death, specifically by apoptosis. Tomentosin-treatment in BL cells induces the downregulation of antiapoptotic genes such as BCL2A1 and CDKN1A and upregulation of the proapoptotic PMAIP1 gene. (4) Overall, our results suggest that tomentosin could be taken into consideration as a potential natural product with limited toxicity and relevant anti-tumoral activity in the therapeutic options available to BL patients.

Clarifying the molecular mechanism of tomentosin‑induced antiproliferative and proapoptotic effects in human multiple myeloma via gene expression profile and genetic interaction network analysis

Multiple myeloma (MM) is an aggressive B cell malignancy. Substantial progress has been made in the therapeutic context for patients with MM, however it still represents an incurable disease due to drug resistance and recurrence. Development of more effective or synergistic therapeutic approaches undoubtedly represents an unmet clinical need. Tomentosin is a bioactive natural sesquiterpene lactone extracted by various plants with therapeutic properties, including anti-neoplastic effects. In the present study, the potential antitumor activity of tomentosin was evaluated on the human RPMI-8226 cell line, treated with increasing tomentosin concentration for cytotoxicity screening. The data suggested that both cell cycle arrest and cell apoptosis could explain the antiproliferative effects of tomentosin and may result in the inhibition of RPMI-8226 cell viability. To assess differentially expressed genes contributing to tomentosin activity and identify its mechanism of action, a microarray gene expression profile was performed, identifying 126 genes deregulated by tomentosin. To address the systems biology and identify how tomentosin deregulates gene expression in MM from a systems perspective, all deregulated genes were submitted to enrichment and molecular network analysis. The Protein-Protein Interaction (PPI) network analysis showed that tomentosin in human MM induced the downregulation of genes involved in several pathways known to lead immune-system processes, such as cytokine-cytokine receptor interaction, chemokine or NF-κB signaling pathway, as well as genes involved in pathways playing a central role in cellular neoplastic processes, such as growth, proliferation, migration, invasion and apoptosis. Tomentosin also induced endoplasmic reticulum stress via upregulation of cyclic AMP-dependent transcription factor ATF-4 and DNA damage-inducible transcript 3 protein genes, suggesting that in the presence of tomentosin the protective unfolded protein response signaling may induce cell apoptosis. The functional connections analysis executed using the Connectivity Map tool, suggested that the effects of tomentosin on RPMI-8226 cells might be similar to those exerted by heat shock proteins inhibitors. Taken together, these data suggested that tomentosin may be a potential drug candidate for the treatment of MM.