Advances in research on the anti-tumor mechanism of Astragalus polysaccharides.

The dry root of the soybean plant Astragalus membranaceus (Fisch) Bge. var. mongholicus (Bge) Hsiao or A. membranaceus (Fisch) Bge, Astragali Radix (AR) has a long medicinal history. Astragalus polysaccharide (APS), the natural macromolecule that exhibits immune regulatory, anti-inflammatory, anti-tumor, and other pharmacological activities, is an important active ingredient extracted from AR. Recently, APS has been increasingly used in cancer therapy owing to its anti-tumor ability as it prevents the progression of prostate, liver, cervical, ovarian, and non-small-cell lung cancer by suppressing tumor cell growth and invasion and enhancing apoptosis. In addition, APS enhances the sensitivity of tumors to antineoplastic agents and improves the body's immunity. This macromolecule has prospects for broad application in tumor therapy through various pathways. In this article, we present the latest progress in the research on the anti-tumor effects of APS and its underlying mechanisms, aiming to provide novel theoretical support and reference for its use in cancer therapy.

Natural polysaccharides exert anti-tumor effects as dendritic cell immune enhancers.

With the development of immunotherapy, the process of tumor treatment is also moving forward. Polysaccharides are biological response modifiers widely found in plants, animals, fungi, and algae and are mainly composed of monosaccharides covalently linked by glycosidic bonds. For a long time, polysaccharides have been widely used clinically to enhance the body's immunity. However, their mechanisms of action in tumor immunotherapy have not been thoroughly explored. Dendritic cells (DCs) are a heterogeneous population of antigen presenting cells (APCs) that play a crucial role in the regulation and maintenance of the immune response. There is growing evidence that polysaccharides can enhance the essential functions of DCs to intervene the immune response. This paper describes the research progress on the anti-tumor immune effects of natural polysaccharides on DCs. These studies show that polysaccharides can act on pattern recognition receptors (PRRs) on the surface of DCs and activate phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT), mitogen-activated protein kinase (MAPK), nuclear factor-κB (NF-κB), Dectin-1/Syk, and other signalling pathways, thereby promoting the main functions of DCs such as maturation, metabolism, antigen uptake and presentation, and activation of T cells, and then play an anti-tumor role. In addition, the application of polysaccharides as adjuvants for DC vaccines, in combination with adoptive immunotherapy and immune checkpoint inhibitors (ICIs), as well as their co-assembly with nanoparticles (NPs) into nano drug delivery systems is also introduced. These results reveal the biological effects of polysaccharides, provide a new perspective for the anti-tumor immunopharmacological research of natural polysaccharides, and provide helpful information for guiding polysaccharides as complementary medicines in cancer immunotherapy.

Anti-tumor mechanism study on saffron by network pharmacology and reverse molecular docking / 药学实践杂志

Objective To explore the anti-tumor mechanism of saffron (Crocus sativus L.) by network pharmacology and reverse molecular docking techniques. Methods The main chemical components of saffron were obtained by searching published literature and TCMSP database. The potential targets of these components were predicted using PharmMapper server. The corresponding target genes were identified from UniProt database. The underlying anti-tumor targets of saffron were obtained by mapping the disease genes of cancer or tumor with GeneCards, OMIM and TTD databases. Cytoscape software was used to construct the action target network of saffron active components. The protein-protein interaction analysis was performed by String database, and the GO function and KEGG pathway enrichment analysis were performed by Metascape platform. Finally, molecular docking was performed to evaluate the binding of main components with their potential targets. Results A total of 9 active ingredients in saffron including quercetin, kaempferol, isorhamnetin, picrocrocin and crocin I, were identified, which might act on 37 key targets including AKT1, CCND1, MMP9, EGFR, TP53, involved in P53, TNF and other signaling pathways. Molecular docking indicated modest binding potency through hydrogen bonding, and hydrophobic interactions. Conclusion The anti-tumor effect of saffron was evaluated via the network of components-targets-pathways, which might provide a foundation for further research.

Salmonella as a Promising Curative Tool against Cancer.

Bacteria-mediated cancer therapy has become a topic of interest under the broad umbrella of oncotherapy. Among many bacterial species, Salmonella remains at the forefront due to its ability to localize and proliferate inside tumor microenvironments and often suppress tumor growth. Salmonella Typhimurium is one of the most promising mediators, with engineering plasticity and cancer specificity. It can be used to deliver toxins that induce cell death in cancer cells specifically, and also as a cancer-specific instrument for immunotherapy by delivering tumor antigens and exposing the tumor environment to the host immune system. Salmonella can be used to deliver prodrug converting enzymes unambiguously against cancer. Though positive responses in Salmonella-mediated cancer treatments are still at a preliminary level, they have paved the way for developing combinatorial therapy with conventional chemotherapy, radiotherapy, and surgery, and can be used synergistically to combat multi-drug resistant and higher-stage cancers. With this background, Salmonella-mediated cancer therapy was approved for clinical trials by U.S. Food and Drug Administration, but the results were not satisfactory and more pre-clinical investigation is needed. This review summarizes the recent advancements in Salmonella-mediated oncotherapy in the fight against cancer. The present article emphasizes the demand for Salmonella mutants with high stringency toward cancer and with amenable elements of safety by virulence deletions.

Structure, anti-tumor activity, and potential anti-tumor mechanism of a fungus polysaccharide from Fomes officinalis.

In our ongoing process of discovering bioactive macromolecules, a homogeneous polysaccharide (FOP80-1) was first purified from Fomes officinalis. FOP80-1 with molecular weight of 4560 Da was mainly composed of →3)-d-Galp-(1→, →4)-ß-d-Manp-(1→, →6)-α-d-Glcp-(1→, →3,6)-d-Glcp-(1→, and t--d-Glcp. Besides the structure features, the anti-tumor activity and potential mechanism of FOP80-1 were also investigated. The cellular and zebrafish experiments revealed that FOP80-1 inhibited tumor proliferation, invasion, and metastasis by increasing ROS, arresting cell cycle, inducing apoptosis, and suppressing angiogenesis. Corresponding to the inhibition of angiogenesis, the surface plasmon resonance (SPR) experiments revealed that FOP80-1 had good affinity with VEGF, a crucial protein to regulate angiogenesis. Molecular docking indicated that FOP80-1 could interact with the protein VEGF.

Natural Marine Products: Anti-Colorectal Cancer In Vitro and In Vivo.

Colorectal cancer, a malignant tumor with high mortality, has a poor prognosis due to drug resistance and toxicity in clinical surgery and chemotherapy. Thus, finding safer and more efficient drugs for clinical trials is vital and urgent. Natural marine compounds, with rich resources and original chemical structures, are applied widely in anticancer treatments. We provide a systematic overview of recently reported marine compounds such as alkaloids, peptides, terpenoids, polysaccharides, and carotenoids from in vitro, in vivo, and clinical studies. The in vitro studies summarized the marine origins and pharmacological mechanisms, including anti-proliferation, anti-angiogenesis, anti-migration, anti-invasion, the acceleration of cycle arrest, and the promotion of tumor apoptosis, of various compounds. The in vivo studies outlined the antitumor effects of marine compounds on colorectal cancer model mice and evaluated their efficacy in terms of tumor inhibition, hepatotoxicity, and nephrotoxicity. The clinical studies summarized the major chemical classifications and targets of action of the clinical drugs that have entered clinical approval and completed approval for marine anticancer. In summary, we present the current situation regarding the application of natural anti-colorectal cancer marine compounds and prospects for their clinical application.

[Anti-tumor mechanism of sesquiterpenoids from Cryptoporus volvatus based on molecular docking].

OBJECTIVE: To identify the target genes mediating anti-tumor effect of sesquiterpenoids from Cryptoporus volvatus and explore the possible mechanism using molecular docking and molecular dynamics simulation. METHODS: Based on the chemical structure of sesquiterpenes from C. volvatus, we explored the online reverse target finding websites PharmMapper, SEA, Target Hunter and related literature for preliminary prediction of possible anti-tumor targets. Discovery Studio 4.0 (Libdock function) and Maestro 12.3 were used to connect sesquiterpenes with the possible targets, and the potential targets were selected according to the scores. The interaction between the sesquiterpenes and the targets were analyzed using 2D interaction diagram, and the influence of different sesquiterpene skeletons on their activity was inferred based on their activity measurements in experiment. Kinetic simulation was performed for front-end protein sequence (1UNQ) of the Akt (protein kinase B) and for the complex formed by 1UNQ and compound 4 (which had the best cytotoxic activity in vitro) in its optimal conformation, and the root mean square deviation (RMSD) value and root mean square float (RMSF) value of the complex and 1UNQ were measured to evaluate the stability of the binding of compound 4 to the target. RESULTS: The sesquiterpenes showed optimal binding with 1UNQ. Analysis of 2D interaction diagram suggested that the hydrogen bonding and electrostatic force were the most important forces mediating the interaction between the sesquiterpenes and 1UNQ. Analysis of the optimal 3D conformation showed that for different sesquiterpenes, a slight change of the molecular framework produced a steric hindrance effect and caused changes in their bioactivity. Kinetic simulation showed that the complex formed by compound 4 and1UNQ had a lower RMSD than the target pure protein sequence, indicating that compound 4 could stably bind to 1UNQ. The anti-tumor effect of the sesquiterpenoids from C. volvatus was associated with their ability to cause Lys-144 acetylation, which blocks Akt binding to the downstream PIP3 and thus affects the proliferation of tumor cells. CONCLUSION: 1UNQ is the target of sesquiterpenoids from C. volvatus, which affects the proliferation of tumor cells by acetylating Lys-14.

Synthesis, biological evaluation and cellular localization study of fluorescent derivatives of Jiyuan Oridonin A.

Jiyuan Oridonin A (JOA) is a naturally occurring ent-kaurane diterpenoid that exhibits significant potential in the field of anti-tumor drug development. However, its detailed anti-cancer mechanism of action has not been fully understood. In order to investigate its anticancer mode of action, two series of novel fluorescent derivatives of JOA conjugated with naphthalimide dyes were synthesized, and their antitumor activity against five selected cancer cell lines (MGC-803, SW1990, PC-3, TE-1 and HGC-27) was evaluated. Compared with JOA, the anti-tumor activity of the vast majority of compounds were improved. Among them, B12 exhibited promising anti-proliferative activity against HGC-27 cells with IC50 value of 0.39 ± 0.09 µM. Fluorescence imaging studies demonstrated that probe B12 could enter HGC-27 cells in a dose-dependent and time-dependent manner and was mainly accumulated in mitochondria. Preliminary biological mechanism studies indicated that B12 was able to inhibit cell cloning and migration. Further studies suggested that B12-induced apoptosis was related to the mitochondrial pathway. Overall, our results provide new approaches to explore the molecular mechanism of the natural product JOA, which would contribute to its further development as an antitumor agent.

Anti-tumor mechanism of sesquiterpenoids from Cryptoporus volvatus based on molecular docking / 南方医科大学学报

OBJECTIVE@#To identify the target genes mediating anti-tumor effect of sesquiterpenoids from Cryptoporus volvatus and explore the possible mechanism using molecular docking and molecular dynamics simulation.@*METHODS@#Based on the chemical structure of sesquiterpenes from C. volvatus, we explored the online reverse target finding websites PharmMapper, SEA, Target Hunter and related literature for preliminary prediction of possible anti-tumor targets. Discovery Studio 4.0 (Libdock function) and Maestro 12.3 were used to connect sesquiterpenes with the possible targets, and the potential targets were selected according to the scores. The interaction between the sesquiterpenes and the targets were analyzed using 2D interaction diagram, and the influence of different sesquiterpene skeletons on their activity was inferred based on their activity measurements in experiment. Kinetic simulation was performed for front-end protein sequence (1UNQ) of the Akt (protein kinase B) and for the complex formed by 1UNQ and compound 4 (which had the best cytotoxic activity in vitro) in its optimal conformation, and the root mean square deviation (RMSD) value and root mean square float (RMSF) value of the complex and 1UNQ were measured to evaluate the stability of the binding of compound 4 to the target.@*RESULTS@#The sesquiterpenes showed optimal binding with 1UNQ. Analysis of 2D interaction diagram suggested that the hydrogen bonding and electrostatic force were the most important forces mediating the interaction between the sesquiterpenes and 1UNQ. Analysis of the optimal 3D conformation showed that for different sesquiterpenes, a slight change of the molecular framework produced a steric hindrance effect and caused changes in their bioactivity. Kinetic simulation showed that the complex formed by compound 4 and1UNQ had a lower RMSD than the target pure protein sequence, indicating that compound 4 could stably bind to 1UNQ. The anti-tumor effect of the sesquiterpenoids from C. volvatus was associated with their ability to cause Lys-144 acetylation, which blocks Akt binding to the downstream PIP3 and thus affects the proliferation of tumor cells.@*CONCLUSION@#1UNQ is the target of sesquiterpenoids from C. volvatus, which affects the proliferation of tumor cells by acetylating Lys-14.

[Progress of studies on anti-breast tumor mechanism of alkaloids].

Breast tumor has become one of the malignant tumors with the highest incidence, and is a serious threat to human health, especially to women. Chemotherapy is an important anti-breast tumor therapy, which can be used in almost every stage of breast tumor therapy alone or in the combination with surgery and radiation therapy. Alkaloids are a kind of ubiquitous natural products, and important active components of various medicinal plants. A large number of studies have shown that alkaloids could exert an anti-breast tumor effect by inhibiting proliferation, metastasis and angiogenesis, resisting mitosis, promoting apoptosis and autophagy, and triggering cell cycle arrest. The extensive anti-breast tumor effect makes alkaloids an important candidate drug source. This paper reviews the anti-breast tumor mechanism of natural products of alkaloids.

Progress of studies on anti-breast tumor mechanism of alkaloids / 中国中药杂志

Breast tumor has become one of the malignant tumors with the highest incidence, and is a serious threat to human health, especially to women. Chemotherapy is an important anti-breast tumor therapy, which can be used in almost every stage of breast tumor therapy alone or in the combination with surgery and radiation therapy. Alkaloids are a kind of ubiquitous natural products, and important active components of various medicinal plants. A large number of studies have shown that alkaloids could exert an anti-breast tumor effect by inhibiting proliferation, metastasis and angiogenesis, resisting mitosis, promoting apoptosis and autophagy, and triggering cell cycle arrest. The extensive anti-breast tumor effect makes alkaloids an important candidate drug source. This paper reviews the anti-breast tumor mechanism of natural products of alkaloids.

Green Tea Polyphenol EGCG Attenuates MDSCs-mediated Immunosuppression through Canonical and Non-Canonical Pathways in a 4T1 Murine Breast Cancer Model.

Several studies in the past decades have reported anti-tumor activity of the bioactive compounds extracted from tea leaves, with a focus on the compound epigallocatechin-3-gallate (EGCG). However, further investigations are required to unravel the underlying mechanisms behind the anti-tumor activity of EGCG. In this study, we demonstrate that EGCG significantly inhibits the growth of 4T1 breast cancer cells in vitro and in vivo. EGCG ameliorated immunosuppression by significantly decreasing the accumulation of myeloid-derived suppressor cells (MDSCs) and increasing the proportions of CD4+ and CD8+ T cells in spleen and tumor sites in 4T1 breast tumor-bearing mice. Surprisingly, a low dose of EGCG (0.5-5 µg/mL) effectively reduced the cell viability and increased the apoptosis rate of MDSCs in vitro. EGCG down-regulated the canonical pathways in MDSCs, mainly through the Arg-1/iNOS/Nox2/NF-κB/STAT3 signaling pathway. Moreover, transcriptomic analysis suggested that EGCG also affected the non-canonical pathways in MDSCs, such as ECM-receptor interaction and focal adhesion. qRT-PCR further validated that EGCG restored nine key genes in MDSCs, including Cxcl3, Vcan, Col4a1, Col8a1, Oasl2, Mmp12, Met, Itsnl and Acot1. Our results provide new insight into the mechanism of EGCG-associated key pathways/genes in MDSCs in the murine breast tumor model.

In Silico Investigation of the Anti-Tumor Mechanisms of Epigallocatechin-3-Gallate.

The EGCG, an important component of polyphenol in green tea, is well known due to its numerous health benefits. We employed the reverse docking method for the identification of the putative targets of EGCG in the anti-tumor target protein database and these targets were further uploaded to public databases in order to understand the underlying pharmacological mechanisms and search for novel EGCG-associated targets. Similarly, the pharmacological linkage between tumor-related proteins and EGCG was manually constructed in order to provide greater insight into the molecular mechanisms through a systematic integration with applicable bioinformatics. The results indicated that the anti-tumor mechanisms of EGCG may involve 12 signaling transduction pathways and 33 vital target proteins. Moreover, we also discovered four novel putative target proteins of EGCG, including IKBKB, KRAS, WEE1 and NTRK1, which are significantly related to tumorigenesis. In conclusion, this work may provide a useful perspective that will improve our understanding of the pharmacological mechanism of EGCG and identify novel potential therapeutic targets.

Mechanisms of Oncolysis by Paramyxovirus Sendai.

Some viral strains of the Paramyxoviridae family may be used as anti-tumor agents. Oncolytic paramyxoviruses include attenuated strains of the measles virus, Newcastle disease virus, and Sendai virus. These viral strains, and the Sendai virus in particular, can preferentially induce the death of malignant, rather than normal, cells. The death of cancer cells results from both direct killing by the virus and through virus-induced activation of anticancer immunity. Sialic-acid-containing glycoproteins that are overexpressed in cancer cells serve as receptors for some oncolytic paramyxoviruses and ensure preferential interaction of paramyxoviruses with malignant cells. Frequent genetic defects in interferon and apoptotic response systems that are common to cancer cells ensure better susceptibility of malignant cells to viruses. The Sendai virus as a Paramyxovirus is capable of inducing the formation of syncytia, multinuclear cell structures which promote viral infection spread within a tumor without virus exposure to host neutralizing antibodies. As a result, the Sendai virus can cause mass killing of malignant cells and tumor destruction. Oncolytic paramyxoviruses can also promote the immune-mediated elimination of malignant cells. In particular, they are powerful inducers of interferon and other cytokynes promoting antitumor activity of various cell components of the immune response, such as dendritic and natural killer cells, as well as cytotoxic T lymphocytes. Taken together these mechanisms explain the impressive oncolytic activity of paramyxoviruses that hold promise as future, efficient anticancer therapeutics.

Anti-tumor mechanisms of microtubule inhibitors / 国际药学研究杂志

Microtubules are a type of dynamic filamentous cytoskeletal protein, and a major component of centrosome. The regular dynamic changes in microtubules are the guarantees of mitosis. Microtubule inhibitors can promote or inhibit tubulin assembly, interfere cell mitosis and the normal structure and function of the spindle, resulting in the inhibition of cell proliferation and tumor specific therapeutic effect. Microtubule inhibitors, targeting different sites, are the key components of chemotherapeutic regiments for various solid tumors, and dozens of microbule inhibitors are already available in market or under clinical study. Including a brief description of the progress in paclitaxel, vinblastine and colchicine, this review systematically introduces the mechanism of a class of microtubule inhibitors.

Anti-Tumor mechanisms of microtubule inhibitors / 国际药学研究杂志

Microtubules are a type of dynamic filamentous cytoskeletal protein, and a major component of centrosome. The regular dynamic changes in microtubules are the guarantees of mitosis. Microtubule inhibitors can promote or inhibit tubulin assembly, interfere cell mitosis and the normal structure and function of the spindle, resulting in the inhibition of cell proliferation and tumor specific therapeutic effect. Microtubule inhibitors, targeting different sites, are the key components of chemotherapeutic regiments for various solid tumors, and dozens of microbule inhibitors are already available in market or under clinical study. Including a brief description of the progress in paclitaxel, vinblastine and colchicine, this review systematically introduces the mechanism of a class of microtubule inhibitors.

Advances in research on the anti-tumor effect of curcumin / 中华临床营养杂志

cancer,and prostatic cancer has been reported.

Anti-tumor mechanisms of arsenic trioxide / 中国普通外科杂志

An overview was prepared haseed on the related articles published in recent years. The anti tumor mechanisms of AsT include: (1)inducing tumor cell apoptosis; (2)inhibiting tumor cell proliferation;and (3)inducing tumor cell differentiation.It is considesed that the study of anti tumor mechanisms of AsT in neoplasms is insufficient except for acute promyelocytic leukemia. The clinical value of AsT in neoplasm treatment is still worthy of studying.