Diosgenin induces death receptor-5 through activation of p38 pathway and promotes TRAIL-induced apoptosis in colon cancer cells

Diosgenin potentiates the anticancer effect of doxorubicin and volasertib via regulating polo-like kinase 1 and triggering apoptosis in hepatocellular carcinoma cells

A common approach to cancer therapy is the combination of a natural product with chemotherapy to overcome sustained cell proliferation and chemotherapy resistance obstacles. Diosgenin (DG) is a phytosteroidal saponin that is naturally present in a vast number of plants and has been shown to exert anti-cancer activities against several tumor cells. Herein, we assessed the chemo-modulatory effects of DG on volasertib (Vola) as a polo-like kinase 1 (PLK1) inhibitor and doxorubicin (DOX) in hepatocellular carcinoma (HCC) cell lines. DOX and Vola were applied to two human HCC cell lines (HepG2 and Huh-7) alone or in combination with DG. The cell viability was determined, and gene expressions of PLK1, PCNA, P53, caspase-3, and PARP1 were evaluated by RT-qPCR. Moreover, apoptosis induction was determined by measuring active caspase-3 level using ELISA method. DG enhanced the anticancer effects of Vola and DOX. Moreover, DG enhanced Vola- and DOX-induced cell death by downregulating the expressions of PLK1 and PCNA, elevating the expressions of P53 and active caspase-3. DG showed promising chemo-modulatory effects to Vola and DOX against HCC that may be attributed partly to the downregulation of PLK1 and PCNA, upregulation of tumor suppressor protein P53, and apoptosis induction. Thus, DG combination with chemotherapy may be a promising treatment approach for HCC.

Advances in antitumor activity and mechanism of natural steroidal saponins: A review of advances, challenges, and future prospects

BACKGROUND

Cancer, the second leading cause of death worldwide following cardiovascular diseases, presents a formidable challenge in clinical settings due to the extensive toxic side effects associated with primary chemotherapy drugs employed for cancer treatment. Furthermore, the emergence of drug resistance against specific chemotherapeutic agents has further complicated the situation. Consequently, there exists an urgent imperative to investigate novel anticancer drugs. Steroidal saponins, a class of natural compounds, have demonstrated notable antitumor efficacy. Nonetheless, their translation into clinical applications has remained unrealized thus far. In light of this, we conducted a comprehensive systematic review elucidating the antitumor activity, underlying mechanisms, and inherent limitations of steroidal saponins. Additionally, we propose a series of strategic approaches and recommendations to augment the antitumor potential of steroidal saponin compounds, thereby offering prospective insights for their eventual clinical implementation.

PURPOSE

This review summarizes steroidal saponins' antitumor activity, mechanisms, and limitations.

METHODS

The data included in this review are sourced from authoritative databases such as PubMed, Web of Science, ScienceDirect, and others.

RESULTS

A comprehensive summary of over 40 steroidal saponin compounds with proven antitumor activity, including their applicable tumor types and structural characteristics, has been compiled. These steroidal saponins can be primarily classified into five categories: spirostanol, isospirostanol, furostanol, steroidal alkaloids, and cholestanol. The isospirostanol and cholestanol saponins are found to have more potent antitumor activity. The primary antitumor mechanisms of these saponins include tumor cell apoptosis, autophagy induction, inhibition of tumor migration, overcoming drug resistance, and cell cycle arrest. However, steroidal saponins have limitations, such as higher cytotoxicity and lower bioavailability. Furthermore, strategies to address these drawbacks have been proposed.

CONCLUSION

In summary, isospirostanol and cholestanol steroidal saponins demonstrate notable antitumor activity and different structural categories of steroidal saponins exhibit variations in their antitumor signaling pathways. However, the clinical application of steroidal saponins in cancer treatment still faces limitations, and further research and development are necessary to advance their potential in tumor therapy.

An In Vitro Study on the Cytotoxic, Antioxidant, and Antimicrobial Properties of Yamogenin-A Plant Steroidal Saponin and Evaluation of Its Mechanism of Action in Gastric Cancer Cells

Yamogenin is a steroidal saponin occurring in plant species such as Asparagus officinalis, Dioscorea collettii, Trigonella foenum-graecum, and Agave sp. In this study, we evaluated in vitro cytotoxic, antioxidant, and antimicrobial properties of yamogenin. The cytotoxic activity was estimated on human colon cancer HCT116, gastric cancer AGS, squamous carcinoma UM-SCC-6 cells, and human normal fibroblasts with MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. The amount of apoptotic and dead AGS cells after treatment with yamogenin was estimated with flow cytometry. Also, in yamogenin-treated AGS cells we investigated the reactive oxygen species (ROS) production, mitochondrial membrane depolarization, activity level of caspase-8 and -9, and gene expression at mRNA level with flow cytometry, luminometry, and RT-PCR, respectively. The antioxidant properties of yamogenin were assessed with DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) assays. The antimicrobial potential of the compound was estimated on Staphylococcus aureus, Bacillus cereus, Klebsiella pneumoniae, Escherichia coli, Salmonella enterica, Helicobacter pylori, Campylobacter coli, Campylobacter jejuni, Listeria monocytogenes, Lactobacillus paracasei, and Lactobacillus acidophilus bacteria strains. Yamogenin showed the strongest cytotoxic effect on AGS cells (IC50 18.50 ± 1.24 µg/mL) among the tested cell lines. This effect was significantly stronger in combinations of yamogenin with oxaliplatin or capecitabine than for the single compounds. Furthermore, yamogenin induced ROS production, depolarized mitochondrial membrane, and increased the activity level of caspase-8 and -9 in AGS cells. RT-PCR analysis revealed that this sapogenin strongly up-regulated TNFRSF25 expression at the mRNA level. These results indicate that yamogenin induced cell death via the extrinsic and intrinsic way of apoptosis. Antioxidant study showed that yamogenin had moderate in vitro potential (IC50 704.7 ± 5.9 µg/mL in DPPH and 631.09 ± 3.51 µg/mL in ABTS assay) as well as the inhibition of protein denaturation properties (with IC50 1421.92 ± 6.06 µg/mL). Antimicrobial test revealed a weak effect of yamogenin on bacteria strains, the strongest one being against S. aureus (with MIC value of 350 µg/mL). In conclusion, yamogenin may be a potential candidate for the treatment and prevention of gastric cancers.

Unleashed Treasures of Solanaceae: Mechanistic Insights into Phytochemicals with Therapeutic Potential for Combatting Human Diseases

Plants that possess a diverse range of bioactive compounds are essential for maintaining human health and survival. The diversity of bioactive compounds with distinct therapeutic potential contributes to their role in health systems, in addition to their function as a source of nutrients. Studies on the genetic makeup and composition of bioactive compounds have revealed them to be rich in steroidal alkaloids, saponins, terpenes, flavonoids, and phenolics. The Solanaceae family, having a rich abundance of bioactive compounds with varying degrees of pharmacological activities, holds significant promise in the management of different diseases. Investigation into Solanum species has revealed them to exhibit a wide range of pharmacological properties, including antioxidant, hepatoprotective, cardioprotective, nephroprotective, anti-inflammatory, and anti-ulcerogenic effects. Phytochemical analysis of isolated compounds such as diosgenin, solamargine, solanine, apigenin, and lupeol has shown them to be cytotoxic in different cancer cell lines, including liver cancer (HepG2, Hep3B, SMMC-772), lung cancer (A549, H441, H520), human breast cancer (HBL-100), and prostate cancer (PC3). Since analysis of their phytochemical constituents has shown them to have a notable effect on several signaling pathways, a great deal of attention has been paid to identifying the biological targets and cellular mechanisms involved therein. Considering the promising aspects of bioactive constituents of different Solanum members, the main emphasis was on finding and reporting notable cultivars, their phytochemical contents, and their pharmacological properties. This review offers mechanistic insights into the bioactive ingredients intended to treat different ailments with the least harmful effects for potential applications in the advancement of medical research.

A review on the impact of TRAIL on cancer signaling and targeting via phytochemicals for possible cancer therapy

Anticancer therapies have been the continual pursuit of this age. Cancer has been ravaging all across the globe breathing not just threats but demonstrating them. Remedies for cancer have been frantically sought after. Few have worked out, yet till date, the available cancer therapies have not delivered a holistic solution. In a world where the search for therapies is levitating towards natural remedies, solutions based on phytochemicals are highly prospective attractions. A lot has been achieved with inputs from plant resources, providing numerous natural remedies. In the current review, we intensely survey the progress achieved in the treatment of cancer through phytochemicals-based programmed cell death of cancer cells. More specifically, we have further reviewed and discussed the role of phytochemicals in activating apoptosis via Tumor Necrosis Factor-Alpha-Related Apoptosis-Inducing Ligand (TRAIL), which is a cell protein that can attach to certain molecules in cancer cells, killing cancer cells. The objective of this review is to enlist the various phytochemicals that are available for specifically contributing towards triggering the TRAIL cell protein-mediated cancer therapy and to point out the research gaps that require future research motivation. This is the first review of this kind in this research direction.

Chinese Yam and Its Active Components Regulate the Structure of Gut Microbiota and Indole-like Metabolites in Anaerobic Fermentation In Vitro

As a medicinal and edible plant, Chinese yam (CY) can promote the enrichment of intestinal probiotics. Mucilage polysaccharides, diosgenin and taxifolin are the dominant components of CY. The purpose of this study was to investigate whether the impact of Chinese yam on gut microbiome structure and metabolism is attributable to its components. In the in vitro gastrointestinal digestion and colon fermentation system, the changes in gut microbiota composition and function were determined by 16S rRNA sequencing, and the levels of bacterial metabolites including short-chain fatty acids (SCFAs) and indole-like metabolites were detected by gas chromatography and an enzyme-linked immunoassay. The results show that CY, mucilage polysaccharides, diosgenin and taxifolin could increase the microbial diversity index. Furthermore, probiotics including Lactobacillus and Bacteroides were significantly increased, while harmful bacteria such as Escherichia and Proteus declined. CY could increase the production of SCFAs including acetic acid and butyric acid. Of note, CY and diosgenin displayed similar impacts on enhancing the abundance of Clostridium and promoting the production of indole-3-lactic acid and lactic acid. These findings provide evidence supporting Chinese yam as a natural food to regulate intestinal health. Diosgenin as a component of CY contributes mostly to the impact on regulating intestinal flora.

Dioscorea nipponica Makino: A comprehensive review of its chemical composition and pharmacology on chronic kidney disease

Chronic kidney disease (CKD) is a widespread ailment that significantly impacts global health. It is characterized by high prevalence, poor prognosis, and substantial healthcare costs, making it a major public health concern. The current clinical treatments for CKD are not entirely satisfactory, leading to a high demand for alternative therapeutic options. Chinese herbal medicine, with its long history, diverse varieties, and proven efficacy, offers a promising avenue for exploration. One such Chinese herbal medicine, Dioscorea nipponica Makino (DNM), is frequently used to treat kidney diseases. In this review, we have compiled studies examining the mechanisms of action of DNM in the context of CKD, focusing on five primary areas: improvement of oxidative stress, inhibition of renal fibrosis, regulation of metabolism, reduction of inflammatory response, and regulation of autophagy.

Antitumoral activity of Caralluma europaea on colorectal and prostate cancer cell lines

Caralluma europaea is a medicinal plant used in Moroccan popular medicine, which has been employed as a remedy attributed to its anti-inflammatory, antipyretic, antinociceptive, antidiabetic, neuroprotective, and antiparasitic properties. The aim of the present study was to investigate the antitumor activity of both the methanolic and aqueous extract of C. europaea. The effects of increasing concentrations of aqueous and methanolic extracts on human colorectal cancer HT-29 and HCT116 cell lines and human prostate cancer PC3 and DU145 cell lines were examined on cell proliferation using MTT assay and cell cycle analysis. The induction of apoptosis was also assessed by determining protein expression of caspase-3 and poly-ADP-ribose polymerase (PARP) cleavage by western blot. The methanolic extract of C. europaea exerted significant antiproliferative effects on HT-29 (IC₅₀ values 73 µg/ml), HCT116 (IC₅₀ values 67 µg/ml), PC3 (IC₅₀ values 63 µg/ml) and DU145 cells (IC₅₀ values 65 µg/ml) after 48 hr treatment. Further, incubation with methanolic extract of C. europaea induced cell cycle arrest in G1 phase and an apoptotic process for all treated cell lines. In conclusion, the present results suggest that C. europaea, exhibited that these natural compounds are significant apoptosis inducers which may have considerable potential for development of effective natural product anticancer agents.

Anticancer Activity of Diosgenin and Its Molecular Mechanism

Diosgenin, a steroidal sapogenin, obtained from Trigonella foenum-graecum, Dioscorea, and Rhizoma polgonati, has shown high potential and interest in the treatment of various cancers such as oral squamous cell carcinoma, laryngeal cancer, esophageal cancer, liver cancer, gastric cancer, lung cancer, cervical cancer, prostate cancer, glioma, and leukemia. This article aims to provide an overview of the in vivo, in vitro, and clinical studies reporting the diosgenin's anticancer effects. Preclinical studies have shown promising effects of diosgenin on inhibiting tumor cell proliferation and growth, promoting apoptosis, inducing differentiation and autophagy, inhibiting tumor cell metastasis and invasion, blocking cell cycle, regulating immunity and improving gut microbiome. Clinical investigations have revealed clinical dosage and safety property of diosgenin. Furthermore, in order to improve the biological activity and bioavailability of diosgenin, this review focuses on the development of diosgenin nano drug carriers, combined drugs and the diosgenin derivatives. However, further designed trials are needed to unravel the diosgenin's deficiencies in clinical application.

Effect of Chitosan-Diosgenin Combination on Wound Healing

The difficult-to-heal wounds continue to be a problem for modern medicine. Chitosan and diosgenin possess anti-inflammatory and antioxidant effects making them relevant substances for wound treatment. That is why this work aimed to study the effect of the combined application of chitosan and diosgenin on a mouse skin wound model. For the purpose, wounds (6 mm diameter) were made on mice's backs and were treated for 9 days with one of the following: 50% ethanol (control), polyethylene glycol (PEG) in 50% ethanol, chitosan and PEG in 50% ethanol (Chs), diosgenin and PEG in 50% ethanol (Dg) and chitosan, diosgenin and PEG in 50% ethanol (ChsDg). Before the first treatment and on the 3rd, 6th and 9th days, the wounds were photographed and their area was determined. On the 9th day, animals were euthanized and wounds' tissues were excised for histological analysis. In addition, the lipid peroxidation (LPO), protein oxidation (POx) and total glutathione (tGSH) levels were measured. The results showed that ChsDg had the most pronounced overall effect on wound area reduction, followed by Chs and PEG. Moreover, the application of ChsDg maintained high levels of tGSH in wound tissues, compared to other substances. It was shown that all tested substances, except ethanol, reduced POx comparable to intact skin levels. Therefore, the combined application of chitosan and diosgenin is a very promising and effective medication for wound healing.

Antioxidant activity of novel diosgenin derivatives: Synthesis, biological evaluation, and in silico ADME prediction

A series of novel diosgenin (DSG) derivatives has been synthesized and tested in vitro for their antioxidant activity. Initially, four analogues have been evaluated for their cytotoxicity using normal human skin fibroblast (NHDF) as model cells. As a result, 84% of NHDF cells were still alive at 5 µM, so these compounds can be considered as innoxious to fibroblasts at this concentration. Then, hemolytic activity against human erythrocytes was studied in order to evaluate the potential impact of tested compounds against normal host cells. The result < 5% of hemolysis rates suggest no lytic activity for most compounds. After that, the main test - evaluation the antioxidant effect of DSG and its new derivatives against lipid peroxidation in the o/w emulsion model - was performed. The most promising compound (8) exhibited the significant antioxidant activity and the biocompatibility towards normal human dermal fibroblasts and red bloods cells. This p-aminobenzoic derivative revealed 61.6% blocking of induced lipid oxidation. Furthermore, eleven predicted ADME properties were predicted for all tested compounds and revealed that they are in compliance with drug-likeness criteria.

Apoptosis evasion via long non-coding RNAs in colorectal cancer

Long non-coding RNA (LncRNA) is a novel and diverse class of regulatory transcripts that are frequently dysregulated in numerous tumor types. LncRNAs are involved in a complicated molecular network, regulating gene expression, and modulating diverse cellular activities in different cancers including colorectal cancer (CRC). Evidence indicates that lncRNAs can be used as a potential biomarker for the prognosis and diagnosis of CRC as they are aberrantly expressed in CRC cells. The high expression or silencing of lncRNAs is associated with cell proliferation, invasion, metastasis, chemoresistance and apoptosis in CRC. LncRNAs exert both pro-apoptotic and anti-apoptotic functions in CRC. The expression of some oncogene lncRNAs is upregulated which leads to the inhibition of apoptotic pathways, similarly, the tumor suppressor lncRNAs are downregulated in CRC. In this review, we describe the function and mechanisms of lncRNAs to regulate the expression of genes that are involved directly or indirectly in controlling cellular apoptosis in CRC. Furthermore, we also discussed the different apoptotic pathways in normal cells and the mechanisms by which CRC evade apoptosis.

Synthesis of Four Steroidal Carbamates with Antitumor Activity against Mouse Colon Carcinoma CT26WT Cells: In Vitro and In Silico Evidence

Colorectal cancer (CRC) is one of the most lethal cancers worldwide. If detected on time, surgery can expand life expectations of patients up to five more years. However, if metastasis has grown deliberately, the use of chemotherapy can play a crucial role in CRC control. Moreover, the lack of selectivity of current anticancer drugs, plus mutations that occur in cancerous cells, demands the development of new chemotherapeutic agents. Several steroids have shown their potentiality as anticancer agents, while some other compounds, such as Taxol and its derivatives bearing a carbamate functionality, have reached the market. In this article, the synthesis, characterization, and antiproliferative activity of four steroidal carbamates on mouse colon carcinoma CT26WT cells are described. Carbamate synthesis occurred via direct reaction between diosgenin, its B-ring modified derivative, and testosterone with phenyl isocyanate under a Brønsted acid catalysis. All obtained compounds were characterized by ¹H and ¹³C Nuclear Magnetic Resonance (NMR), High Resolution Mass Spectroscopy (HRMS); their melting points are also reported. Results obtained from antiproliferative activity assays indicated that carbamates compounds have inhibitory effects on the growth of this colon cancer cell line. A molecular docking study carried out on Human Prostaglandin E Receptor (EP4) showed a high affinity between carbamates and protein, thus providing a valuable theoretical explanation of the in vitro results.

Study on the Mechanism of Diosgenin Targeting STAT3 to Inhibit Colon Cancer Proliferation and Migration

To elucidate regulatory effects and molecular mechanisms of diosgenin on colon cancer, this study administered diosgenin at concentrations of 10 (low), 50 (medium), and 100 μmol/L (high concentration group) at the cell level, respectively. EdU, colony formation, and Transwell assays were implemented to determine SW480 cellular proliferation and migration. Assays of flow cytometry and TUNEL were employed to estimate cell apoptosis. Additionally, nude mouse tumorigenesis assay was used to further verify the regulatory function of diosgenin on colon cancer. The target protein of diosgenin was predicted via molecular docking. The results showed that all three concentrations of diosgenin could reduce colon cancer cellular proliferation and migration, and after diosgenin treatment, colon cancer cellular apoptosis was markedly increased, and the 100 μmol/L diosgenin group produced the most satisfactory inhibition on colon cancer cell proliferation. Ki67 expression was markedly reduced whereas those of Bax and caspase3 were greatly increased after diosgenin treatment. The nude mouse tumorigenesis assay indicated that the parameters of tumorous volume and mass of diosgenin treatment group were greatly decreased as compared to control, and as the concentration of diosgenin increased, the inhibitory effect was more significant. Molecular docking indicated that STAT3 served as a target protein of diosgenin. Moreover, after diosgenin treatment on colon cancer cells, the STAT3 expression was markedly reduced. The STAT3 overexpression would counteract the inhibitory effect of 50 μmol/L diosgenin in both suppressing colon cancer cellular proliferation and migration and promoting apoptosis. Taken together, all our outcomes demonstrated the diosgenin effects in not only inhibiting colon cancer cellular proliferation and migration but also promoting cancerous cellular apoptosis. Diosgenin is a regulatory player in targeting and regulating STAT3.

Diosgenin derivatives developed from Pd(II) catalysed dehydrogenative coupling exert an effect on breast cancer cells by abrogating their growth and facilitating apoptosis via regulating the AKT1 pathway

Palladium metallates containing 4-oxo-4H-chromene-3-carbaldehyde derived ONS donor Schiff bases were synthesized and their efficacy was tested in the direct amination of diosgenin - a phyto steroid. Based on the pharmacological importance of diosgenin, the obtained derivatives were exposed to study their effect on breast cancer cells where they significantly reduced the growth of cancer cells and left non-malignant breast epithelial cells unaffected. Among the derivatives, D3, D4 and D6 showed a better anti-proliferative effect and further analysis revealed that the D3, D4 and D6 derivatives markedly promoted cell cycle arrest and apoptosis by attenuation of the AKT1 signalling pathway.

Modulation of TLR/NF-κB/NLRP Signaling by Bioactive Phytocompounds: A Promising Strategy to Augment Cancer Chemotherapy and Immunotherapy

Background

Tumors often progress to a more aggressive phenotype to resist drugs. Multiple dysregulated pathways are behind this tumor behavior which is known as cancer chemoresistance. Thus, there is an emerging need to discover pivotal signaling pathways involved in the resistance to chemotherapeutic agents and cancer immunotherapy. Reports indicate the critical role of the toll-like receptor (TLR)/nuclear factor-κB (NF-κB)/Nod-like receptor pyrin domain-containing (NLRP) pathway in cancer initiation, progression, and development. Therefore, targeting TLR/NF-κB/NLRP signaling is a promising strategy to augment cancer chemotherapy and immunotherapy and to combat chemoresistance. Considering the potential of phytochemicals in the regulation of multiple dysregulated pathways during cancer initiation, promotion, and progression, such compounds could be suitable candidates against cancer chemoresistance.

Objectives

This is the first comprehensive and systematic review regarding the role of phytochemicals in the mitigation of chemoresistance by regulating the TLR/NF-κB/NLRP signaling pathway in chemotherapy and immunotherapy.

Methods

A comprehensive and systematic review was designed based on Web of Science, PubMed, Scopus, and Cochrane electronic databases. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed to include papers on TLR/NF-κB/NLRP and chemotherapy/immunotherapy/chemoresistance by phytochemicals.

Results

Phytochemicals are promising multi-targeting candidates against the TLR/NF-κB/NLRP signaling pathway and interconnected mediators. Employing phenolic compounds, alkaloids, terpenoids, and sulfur compounds could be a promising strategy for managing cancer chemoresistance through the modulation of the TLR/NF-κB/NLRP signaling pathway. Novel delivery systems of phytochemicals in cancer chemotherapy/immunotherapy are also highlighted.

Conclusion

Targeting TLR/NF-κB/NLRP signaling with bioactive phytocompounds reverses chemoresistance and improves the outcome for chemotherapy and immunotherapy in both preclinical and clinical stages.

Cytotoxic activity of standardized extracts, a fraction, and individual secondary metabolites from fenugreek seeds against SKOV-3, HeLa and MOLT-4 cell lines

CONTEXT

Trigonella foenum-graecum L. (Fabaceae) has many therapeutic properties and anticancer potential.

OBJECTIVE

The cytotoxic activities of standardized extracts and a fraction from fenugreek seeds and their compounds (sapogenins, flavone C-glycosides, alkaloid trigonelline) against human cancer SKOV-3, HeLa and MOLT-4 cells were evaluated.

MATERIALS AND METHODS

Fenugreek seeds were extracted with 70% methanol (A) or water (B). Furthermore, the seeds were purified with petroleum ether and chloroform and next extracted with methanol to obtain fraction (C). The quantitative analysis of saponins and flavonoids in the extracts was done with HPLC methods. The extracts (5-120 µg/mL) and compounds (1-50 µg/mL) were tested on the cells by MTT assay and RTCA system. The effect of a fraction on ROS production, mitochondrial membrane potential and caspase-3/7 activity in HeLa and SKOV-3 cells was also evaluated by flow cytometry.

RESULTS

The strongest cytotoxic activity on cancer cells showed the fraction C (IC₅₀ was 3.91 ± 0.03 for HeLa, 3.97 ± 0.07 for SKOV-3, and 7.75 ± 0.37 for MOLT-4) with the highest content of steroidal saponins (163.18 ± 11.03 μg/mg) and flavone C-glycosides (820.18 ± 0.05 μg/mg). The fraction significantly increased ROS production (up to four times higher than in keratinocytes as control) and caspases activity in the cells. The examined flavonoids did not exhibit the cytotoxic activity in contrast to yamogenin, tigogenin, and diosgenin.

CONCLUSIONS

The obtained results complement the data on the cytotoxic activity of Foenugraeci Semen and synergistic effect of flavonoids and saponins complex contained in the plant.

Comprehensive review on signaling pathways of dietary saponins in cancer cells suppression

Nutrigenomics utilizes high-throughput genomic technologies to reveal changes in gene and protein levels. Excitingly, ever-growing body of scientific findings has provided sufficient evidence about the interplay between diet and genes. Cutting-edge research and advancements in genomics, epigenetics and metabolomics have deepened our understanding on the role of dietary factors in the inhibition of carcinogenesis and metastasis. Dietary saponins, a type of triterpene glycosides, are generally found in Platycodon grandifloras, Dioscorea oppositifolia, asparagus, legumes, and sea cucumber. Wealth of information has started to shed light on pleiotropic mechanistic roles of dietary saponins in cancer prevention and inhibition. In this review, we have attempted to summarize the in vitro research of dietary saponins in the last two decades by searching common databases such as Google Scholar, PubMed, Scopus, and Web of Science. The results showed that dietary saponins exerted anti-cancer activities via regulation of apoptosis, autophagy, arrest cell cycle, anti-proliferation, anti-metastasis, and anti-angiogenesis, by regulation of several critical signaling pathways, including MAPK, PI3K/Akt/mTOR, NF-κB, and VEGF/VEGFR. However, there is no data about the dosage of dietary saponins for practical anti-cancer effects in human bodies. Extensive clinical studies are needed to confirm the effectiveness of dietary saponins for further commercial and medical applications.

Novel diosgenin-1,4-quinone hybrids: Synthesis, antitumor evaluation, and mechanism studies

In this research, a series of novel diosgenin-1,4-quinone hybrids were synthesized and evaluated in antiproliferative assays against three human cancer cell lines (MCF-7, HepG2, and HeLa). Structure-activity relationship analysis revealed that the activities depended on the type of 1,4-quinone moiety. Among them, hybrid 11a exhibited significant cytotoxicity against the HepG2 cell line with a IC₅₀ of 1.76 μM, which was 35-fold more potent than diosgenin (IC₅₀ = 43.96 μM). Western blot analysis showed that hybrid 11a upregulated Bax, Cl-caspase-3/9, and Cl-PARP levels, and downregulated Bcl-2 level of HepG2 cell line. Meanwhile, hybrid 11a could increase the generation of intracellular reactive oxygen species. The molecular docking study revealed an interaction between hybrid 11a and NQO1 enzyme. Our present studies suggested that hybrid 11a as a potential substrate for NQO1 enzyme could be a promising anticancer agent for further investigation.

Diosgenin Protects Against Kidney Injury and Mitochondrial Apoptosis Induced by 3-MCPD Through the Regulation of ER Stress, Ca2+ Homeostasis, and Bcl2 Expression

SCOPE

Diosgenin (DIO) is a natural steroid sapogenin presented in various plants. It exerts anti-oxidant, anti-inflammatory and anti-diabetic nephropathy properties. The present study evaluates the intervention effect of DIO on nephrotoxicity induced by food contaminant 3-chloro-1, 2-propanediol (3-MCPD) in vivo and in vitro.

METHODS AND RESULTS

Treatment with DIO (15 mg kg-1 d-1 ) in Sprague-Dawley rats for 4-week relieves kidney injury induced by 3-MCPD (30 mg kg-1 d-1 ). In vitro, DIO (2, 6, and 8 µM) alleviates cell injury and apoptosis effectively in human embryonic kidney (HEK293) cells. DIO realizes its protective function via the regulation of endoplasmic reticulum (ER) stress and mitochondrial apoptosis pathway. Blockage of ER stress by 4-phenylbutyric acid (4-PBA), a specific ER stress antagonist, inhibits mitochondrial apoptosis, suggesting a connection between mitochondrial apoptosis and ER stress. Furthermore, the study demonstrates that the maintenance of Ca2+ homeostasis and Bcl2 expression, two main targets of ER stress, contributes to the protection role of DIO on mitochondrial-dependent apoptosis. In addition, DIO relieves the impairment of oxidative phosphorylation.

CONCLUSION

This study demonstrates that DIO exerts protective effect against kidney injury, mitochondrial dysfunction, and apoptosis through the inhibition of ER stress and the further maintenance of Ca2+ homeostasis and Bcl2 expression.

Diosgenin exerts anti-tumor effects through inactivation of cAMP/PKA/CREB signaling pathway in colorectal cancer

Colorectal cancer (CRC) is the most fatal gastrointestinal tumor and it is urge to explore powerful drugs for the treatment. Diosgenin (DSG) as a new steroidal had been reported exerts anti-tumor activity in multiple cancers, including CRC. However, the potential mechanism of DSG suppresses CRC remains further to be revealed. Here, we reported that DSG inhibited proliferation of CRC cells in dose- and time-dependent manner, induced apoptosis by modulating p53 and Bcl-2 family proteins expression to mediate mitochondrial apoptosis pathway, suppressed migration and invasion by reducing MMP-9 (matrix metalloproteinase) and decreased aerobic glycolysis by mediating glucose transporter (GLUT) like GLUT3 and GLUT4, and pyruvate carboxylase PC downregulation. Intriguingly, mechanistic study suggests those phenotypes involved DSG inhibited cAMP/PKA/CREB pathway in CRC cells, and result to inhibit the phosphorylation of CREB to regulate the transcription of genes above-mentioned. Finally, nude mice xenograft tumor model further indicated that DSG could be a great agent to suppress the growth of CRC cells in vivo and have no obvious side effects. Taken together, we revealed a unique mechanism that DSG suppresses CRC cells through cAMP/PKA/CREB pathway and DSG is a promising candidate drug for CRC treatment.

Diosgenin and galactomannans, natural products in the pharmaceutical sciences

Background

Diosgenin is an isospirostane derivative, which is a steroidal sapogenin and the product of acids or enzymes hydrolysis process of dioscin and protodioscin. Galactomannans are heteropolysaccharides composed of D-mannose and D-galactose, which are major sources of locust bean, guar, tara and fenugreek.

Methods

Literature survey was accomplished using multiple databases including PubMed, Science Direct, ISI web of knowledge and Google Scholar.

Results

Four major sources of seed galactomannans are locust bean (Ceratonia siliqua), guar (Cyamopsis tetragonoloba), tara (Caesalpinia spinosa Kuntze), and fenugreek (T.foenum-graecum). Diosgenin has effect on immune system, lipid system, inflammatory and reproductive systems, caner, metabolic process, blood system, blood glucose and calcium regulation. The most important pharmacological benefits of galactomannan are antidiabetic, antioxidant, anticancer, anticholinesterase, antiviral activities, and appropriate for dengue virus and gastric diseases.

Conclusions

Considering the importance of diosgenin and galactomannans, the obtained findings suggest potential of diosgenin and galactomannans as natural products in pharmaceutical industries.

Synthesis and biological evaluation of chalcone-polyamine conjugates as novel vectorized agents in colorectal and prostate cancer chemotherapy

The aim of this study was to synthesize chalcone-polyamine conjugates in order to enhance bioavailability and selectivity of chalcone core towards cancer cells, using polyamine-based vectors. Indeed, it is well-known that polyamine transport system is upregulated in tumor cells. 3',4,4',5'-tetramethoxychalcone was selected as parent chalcone since it was found to be an efficient anti-proliferative agent on various cancer cells. A series of five chalcone-polyamine conjugates was obtained using the 4-bromopropyloxy-3',4',5'-trimethoxychalcone as a key intermediate. Chalcone core and polyamine tails were fused through an amine bond. These conjugates were found to possess a marked in vitro antiproliferative effect against colorectal (HT-29 and HCT-116) and prostate cancer (PC-3 and DU-145) cell lines. The most active conjugate (compound 8b) was then chosen for further biological evaluations to elucidate mechanisms responsible for its antiproliferative activity. Investigations on cell cycle distribution revealed that this conjugate can prevent the proliferation of human colorectal and prostate cancer cells by blocking the cell cycle at the G1 and G2 phase, respectively. Flow cytometry analysis revealed a sub-G1 peak, characteristic of apoptotic cell population and our inquiries highlighted apoptosis induction at early and later stages through several pro-apoptotic markers. Therefore, this chalcone-N1-spermidine conjugate could be considered as a promising agent for colon and prostatic cancer adjuvant therapy.

Diosgenin Derivatives as Potential Antitumor Agents: Synthesis, Cytotoxicity, and Mechanism of Action

Thirty-two new diosgenin derivatives were designed, synthesized, and evaluated for their cytotoxic activities in three human cancer cell lines (A549, MCF-7, and HepG2) and normal human liver cells (L02) using an MTT assay in vitro. Most compounds, especially 8, 18, 26, and 30, were more potent when compared with diosgenin. The structure-activity relationship results suggested that the presence of a succinic acid or glutaric acid linker, a piperazinyl amide terminus, and lipophilic cations are all beneficial for promoting cytotoxic activity. Notably, compound 8 displayed excellent cytotoxic activity against HepG2 cells (IC₅₀ = 1.9 μM) and showed relatively low toxicity against L02 cells (IC₅₀ = 18.6 μM), showing some selectivity between normal and tumor cells. Studies on its cellular mechanism of action showed that compound 8 induces G0/G1 cell cycle arrest and apoptosis in HepG2 cells. Predictive studies indicated that p38α mitogen-activated protein kinase (MAPK) is the optimum target of 8 based on its 3D molecular similarity, and docking studies showed that compound 8 fits well into the active site of p38α-MAPK and forms relatively strong interactions with the surrounding amino acid residues. Accordingly, compound 8 may be used as a promising lead compound for the development of new antitumor agents.

Network Pharmacology Interpretation of Fuzheng-Jiedu Decoction against Colorectal Cancer

Introduction

Traditional Chinese medicine (TCM) believes that the pathogenic factors of colorectal cancer (CRC) are “deficiency, dampness, stasis, and toxin,” and Fuzheng–Jiedu Decoction (FJD) can resist these factors. In this study, we want to find out the potential targets and pathways of FJD in the treatment of CRC and also explain from a scientific point of view that FJD multidrug combination can resist “deficiency, dampness, stasis, and toxin.”

Methods

We get the composition of FJD from the TCMSP database and get its potential target. We also get the potential target of colorectal cancer according to the OMIM Database, TTD Database, GeneCards Database, CTD Database, DrugBank Database, and DisGeNET Database. Subsequently, PPI analysis, KEGG pathways analysis, and GO biological processes analysis were carried out for the target of FJD in the therapy of colorectal cancer. In addition, we have also built a relevant network diagram.

Results

In this study, we identified four core compounds of FJD in the therapy of colorectal cancer, including quercetin, kaempferol, beta-sitosterol, and stigmasterol. At the same time, we also obtained 30 core targets, including STAT3, INS, TP53, VEGFA, AKT1, TNF, IL6, JUN, EGF, CASP3, MAPK3, MAPK1, MAPK8, SRC, IGF1, CCND1, ESR1, EGFR, PTEN, MTOR, FOS, PTGS2, CXCL8, HRAS, CDH1, BCL2L1, FN1, MMP9, ERBB2, and JAK2. FJD treatment of colorectal cancer mainly involves 112 KEGG pathways, including FoxO (hsa04068) signaling pathway, PI3K-Akt (hsa04151) signaling pathway, HIF-1 (hsa04066) signaling pathway, T cell receptor (hsa04660) signaling pathway, and ErbB (hsa04012) signaling pathway. At the same time, 330 GO biological processes were summarized, including cell proliferation, cell apoptosis, angiogenesis, inflammation, and immune.

Conclusions

In this study, we found that FJD can regulate cell proliferation, apoptosis, inflammation and immunity, and angiogenesis through PI3K-Akt signaling pathway to play an anti-CRC effect.

Biotechnological strategies for the sustainable production of diosgenin from Dioscorea spp

Diosgenin is a plant-derived secondary metabolite mainly present in the members of the plant family Dioscoreaceae. It is a pharmaceutically important compound because of its anti-cancerous, anti-diabetic, anticoagulant, anti-thrombosis, anti-inflammatory, anti-viral, anti-ageing and other properties. Biotechnology provides an opportunity to genetically manipulate cells, tissues, organs or the whole organisms by propagating them in vitro in order to harvest the bioactive compounds. Diosgenin production from botanical sources is being improved by in vitro techniques which include elicitation, genetic transformations and bioconversions. Various techniques have been developed to obtain compounds for drug detection including separation from plants and other natural sources, molecular modelling, synthetic chemistry and combinatorial chemistry. Development in molecular markers determines genetic relationship, genetic linkage map construction, genetic diversity and identification. For rapid clonal propagation and ex situ conservation, the in vitro tools involving plant cell, tissue and organ culture have been well documented for plant-derived diosgenin production. The present review encompasses the wide application of the biotechnological techniques for diosgenin production via elucidating its biosynthetic pathway, in vitro production and mass propagation and elicitation. In addition, molecular marker-mediated diversity assessment of diosgenin containing plant species is also discussed. The review also presents the recent literature to explore the limitations of the relevant studies and future direction of research on production of diosgenin from Dioscorea spp. KEY POINTS: • Critical and updated assessment on sustainable production of diosgenin from Dioscorea spp. • In vitro propagation of Dioscorea spp. and elicitation of diosgenin production. • Diversity assessment of Dioscorea spp. using molecular markers.

Targeting Lipid Peroxidation for Cancer Treatment

Cancer is one of the highest prevalent diseases in humans. The chances of surviving cancer and its prognosis are very dependent on the affected tissue, body location, and stage at which the disease is diagnosed. Researchers and pharmaceutical companies worldwide are pursuing many attempts to look for compounds to treat this malignancy. Most of the current strategies to fight cancer implicate the use of compounds acting on DNA damage checkpoints, non-receptor tyrosine kinases activities, regulators of the hedgehog signaling pathways, and metabolic adaptations placed in cancer. In the last decade, the finding of a lipid peroxidation increase linked to 15-lipoxygenases isoform 1 (15-LOX-1) activity stimulation has been found in specific successful treatments against cancer. This discovery contrasts with the production of other lipid oxidation signatures generated by stimulation of other lipoxygenases such as 5-LOX and 12-LOX, and cyclooxygenase (COX-2) activities, which have been suggested as cancer biomarkers and which inhibitors present anti-tumoral and antiproliferative activities. These findings support the previously proposed role of lipid hydroperoxides and their metabolites as cancer cell mediators. Depletion or promotion of lipid peroxidation is generally related to a specific production source associated with a cancer stage or tissue in which cancer originates. This review highlights the potential therapeutical use of chemical derivatives to stimulate or block specific cellular routes to generate lipid hydroperoxides to treat this disease.

Inhibition of invadopodia formation by diosgenin in tumor cells

Diosgenin is a type of steroid extracted from the rhizome of Dioscorea plants. In traditional Chinese medicine, Dioscorea has the effect of ‘eliminating phlegm, promoting digestion, relaxing tendons, promoting blood circulation and inhibiting malaria’. Recent studies have confirmed that diosgenin exhibits a number of pharmacological effects, including antitumor activities. Through its antitumor effect, diosgenin is able to block tumor progression and increase the survival rate of patients with cancer; ultimately improving their quality of life. However, the mechanism underlying its pharmacological action remains unclear. Once tumor cells reach a metastatic phase, it can be fatal. Increased migration and invasiveness are the hallmarks of metastatic tumor cells. Invadopodia formation is key to maintaining the high migration and invasive ability of tumor cells. Invadopodia are a type of membrane structure process rich in filamentous-actin and are common in highly invasive tumor cells. In addition to actin, numerous actin regulators, including cortical actin-binding protein (Cortactin), accumulate in invadopodia. Cortactin is a microfilament actin-binding protein with special repetitive domains that are directly involved in the formation of the cortical microfilament actin cell skeleton. Cortactin is also one of the main substrates of intracellular Src-type tyrosine protein kinases and represents a highly conserved family of intracellular cortical signaling proteins. In recent years, great progress has been made in understanding the role of Cortactin and its molecular mechanism in cell motility. However, the diosgenin-Cortactin-invadopodia mechanism is still under investigation. Therefore, the present review focused on the current research on the regulation of invadopodia by diosgenin via Cortactin.

Diosgenin, a steroidal saponin, and its analogs: Effective therapies against different chronic diseases

BACKGROUND

Chronic diseases are a major cause of mortality worldwide, and despite the recent development in treatment modalities, synthetic drugs have continued to show toxic side effects and development of chemoresistance, thereby limiting their application. The use of phytochemicals has gained attention as they show minimal side effects. Diosgenin is one such phytochemical which has gained importance for its efficacy against the life-threatening diseases, such as cardiovascular diseases, cancer, nervous system disorders, asthma, arthritis, diabetes, and many more.

AIM

To evaluate the literature available on the potential of diosgenin and its analogs in modulating different molecular targets leading to the prevention and treatment of chronic diseases.

METHOD

A detailed literature search has been carried out on PubMed for gathering information related to the sources, biosynthesis, physicochemical properties, biological activities, pharmacokinetics, bioavailability and toxicity of diosgenin and its analogs.

KEY FINDINGS

The literature search resulted in many in vitro, in vivo and clinical trials that reported the efficacy of diosgenin and its analogs in modulating important molecular targets and signaling pathways such as PI3K/AKT/mTOR, JAK/STAT, NF-κB, MAPK, etc., which play a crucial role in the development of most of the diseases. Reports have also revealed the safety of the compound and the adaptation of nanotechnological approaches for enhancing its bioavailability and pharmacokinetic properties.

SIGNIFICANCE

Thus, the review summarizes the efficacy of diosgenin and its analogs for developing as a potent drug against several chronic diseases.

Diosgenin and GSK126 Produce Synergistic Effects on Epithelial-Mesenchymal Transition in Gastric Cancer Cells by Mediating EZH2 via the Rho/ROCK Signaling Pathway

Background

Diosgenin, a natural steroidal saponin isolated from Trigonella foenum-graecum, has been reported to exert anti-cancer effects. Inhibitors of enhancer of zeste homology 2 (EZH2) have been widely used in treatment of cancers. However, the effects of combined treatment with diosgenin and an EZH2 inhibitor on gastric cancer (GC) cells, and the mechanism for those effects are not fully understood.

Methods

AGS and SGC-7901 gastric cancer cells were treated with diosgenin (0 to 8 μM), followed by treatment with either diosgenin or an EZH2 inhibitor, GSK126 alone. Afterwards, an EZH2 overexpression plasmid and Rho inhibitor, GSK429286A was involved in cells. Cell proliferation, cell cycle distribution, and cell apoptosis, migration, and invasion were examined by CCK-8 assays, flow cytometry, and transwell assays. Western blotting was performed to detect the relative levels of protein expression.

Results

Treatment with diosgenin alone caused a dose-dependent decrease in the cell viability, and combined treatment with an EZH2 inhibitor plus GSK126 caused a further significant decrease. A further analysis revealed that treatment with either diosgenin or GSK126 alone induced significant increases in G0/G1 cell cycle arrest and apoptosis, and combined treatment with both agents induced further increases in those parameters. In addition, combined treatment with diosgenin and GSK126 synergistically induced even stronger effects on impaired cell proliferation, G0/G1 phase arrest, and cell apoptosis when compared to treatment with either diosgenin or GSK126 treatment alone. At the molecular level, we demonstrated that inhibition of Rho/ROCK signaling by combined treatment with diosgenin and GSK126 could downregulate the expression of epithelial–mesenchymal transition (EMT)-related molecules. We also found that EZH2 overexpression reversed the anti-tumor effect of diosgenin by inducing cell survival, blocking G1-phase arrest, and promoted EMT. While, these biological properties were further reversed by GSK429286A.

Conclusion

Collectively, combined treatment with diosgenin and GSK126 produced even more significant effects on GC cell inhibition by targeting EZH2 via Rho/ROCK signaling-mediated EMT, which might be a therapeutic strategy for improving the poor therapeutic outcomes obtained with GSK126 monotherapy.

Elucidation of colon-protective efficacy of diosgenin in experimental TNBS-induced colitis: inhibition of NF-κB/IkB-α and Bax/Caspase-1 signaling pathways

The aim of present investigation was to elucidate the unrevealed beneficial role of diosgenin against an experimental model of TNBS (2,4,6-trinitrobenzenesufonic acid)-induced ulcerative colitis (UC). Colitis was induced in Sprague-Dawley rats by intrarectal administration of TNBS (in 50% ethanol). Then animals were treated with diosgenin (50, 100, and 200 mg/kg) for 14 days. Various biochemical, behavioral, molecular, and histological analysis was performed. Diosgenin significantly decreased (p < 0.05) TNBS-induced elevated colonic oxido-nitrosative damage, myeloperoxidase, hydroxyproline, mRNA expressions of proinflammatory cytokines (TNF-α, IL-1β, IL-6, and IFN-γ) and inflammatory markers (iNOs and COX-2) induced by TNBS. Western blot analysis relevated that TNBS-induced up-regulated protein expressions of NF-κB, IκBα, Bax, and Caspase-1 were markedly decreased (p < 0.05) by diosgenin treatment. It also markedly ameliorated the histological insults induced in the colon by TNBS. In conclusion, diosgenin exerts its colon-protective efficacy probably through the inhibition of NF-κB/IkB-α and Bax/Caspase-1 signaling pathways to experimental TNBS-induced ulcerative colitis.

ABBREVIATIONS

ANOVA: Analysis of variance; 5-ASA: 5-aminosalicylic acid; Bax: Bcl-2-associated X protein; COX-2: Cyclooxygenase-2; DAI: Disease Activity Index; DMSO: Dimethyl sulfoxide; GAPDH: Glyceraldehyde 3-phosphate dehydrogenase; GSH: Glutathione; HP: Hydroxyproline; IAEC: International Animal Ethics Committee; IBD: Inflammatory Bowel Disease; IBS: Inflammatory Bowel Syndrome; IL's: Interleukin's; IFN-γ: Interferon-gamma; IκBα: nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor-alpha; iNOs: Inducible nitric oxide synthase; LTB4: Leukotriene B4; MDA: Malondialdehyde; MPO: Myeloperoxidase; NO: Nitric Oxide; NF-κB: Nuclear Factor-κB; ROS: Reactive Oxygen Species; SOD: Superoxide Dismutase; TNBS: Trinitrobenzene Sulfonic Acid; TNF-α: Tumor necrosis factor-α.

Bivalent furostene carbamates as antiproliferative and antiinflammatory agents

Breast cancer is the most prevalent cancer in women affecting about 12% of world's female population. It is a multifactorial disease, mostly invasive in nature. Diosgenin and related compounds are potent antiproliferative agents. Carbamate derivatives have been synthesized at C26 of furostene ring after opening spiroketal bond (F-ring) of diosgenin. Compound 10 possessed significant antiproliferative activity against human breast cancer cells by arresting the population at G1 phase of cell division cycle and induced apoptosis. Induction of apoptosis was observed through the caspase signalling cascade by activating caspase-3. Moreover, carbamate 10 exhibited moderate antiinflammatory activity by decreasing the expression of cytokines, TNF-α and IL-6 in LPS-induced inflammation in primary macrophage cells. Furthermore, compound 10 significantly reduced Ehrlich ascites carcinoma significantly in mice. It was well tolerated and safe in acute oral toxicity in Swiss albino mice. The concomitant anticancer and antiinflammatory properties of carbamate 10 are important and thus, can further be optimized for a better anti-breast cancer candidate.

Photodynamic Therapy Activity of New Porphyrin-Xylan-Coated Silica Nanoparticles in Human Colorectal Cancer

Photodynamic therapy (PDT) using porphyrins has been approved for treatment of several solid tumors due to the generation of cytotoxic reactive oxygen species (ROS). However, low physiological solubility and lack of selectivity towards tumor sites are the main limitations of their clinical use. Nanoparticles are able to spontaneously accumulate in solid tumors through an enhanced permeability and retention (EPR) effect due to leaky vasculature, poor lymphatic drainage, and increased vessel permeability. Herein, we proved the added value of nanoparticle vectorization on anticancer efficacy and tumor-targeting by 5-(4-hydroxyphenyl)-10,15,20-triphenylporphyrin (TPPOH). Using 80 nm silica nanoparticles (SNPs) coated with xylan-TPPOH conjugate (TPPOH-X), we first showed very significant phototoxic effects of TPPOH-X SNPs mediated by post-PDT ROS generation and stronger cell uptake in human colorectal cancer cell lines compared to free TPPOH. Additionally, we demonstrated apoptotic cell death induced by TPPOH-X SNPs-PDT and the interest of autophagy inhibition to increase anticancer efficacy. Finally, we highlighted in vivo, without toxicity, elevated anticancer efficacy of TPPOH-X SNPs through improvement of tumor-targeting compared to a free TPPOH protocol. Our work demonstrated for the first time the strong anticancer efficacy of TPPOH in vitro and in vivo and the merit of SNPs vectorization.

Caudatin potentiates the anti-tumor effects of TRAIL against human breast cancer by upregulating DR5

BACKGROUND

The ability of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) to preferentially induce apoptosis in transformed cells while sparing most normal cells is well established. However, the intrinsic and acquired resistance of tumors to TRAIL-induced apoptosis limits its therapeutic applicability.

PURPOSE

We investigated the effect of caudatin, a species of C-21 steroidal glycosides isolated from the roots of Cynanchum auriculatum, on TRAIL-induced apoptosis in human breast cancer cells.

METHODS

Cell growth inhibition was evaluated by the CCK-8 assay. The cell cycle distribution was assessed by propidium iodide flow cytometry. Apoptosis was determined by TUNEL staining. Protein expression was detected by western blotting analysis.

RESULTS

Caudatin enhanced TRAIL-induced apoptosis in human breast cancer cells. This sensitization was achieved by upregulating death receptor 5 (DR5). Knockdown of DR5 abolished the enhancing effect of caudatin on TRAIL responses. The caudatin-induced upregulation of DR5 was accompanied by increased expression of CHOP and phosphorylation of p38 MAPK and JNK. CHOP knockdown blocked caudatin-upregulated DR5 expression. Moreover, cotreatment of breast cancer cells with p38 MAPK and JNK inhibitors significantly counteracted the caudatin-induced expression of DR5.

CONCLUSION

Our results showed that caudatin sensitized breast cancer cells to TRAIL-induced apoptosis through activation of CHOP, p38 MAPK and JNK-mediated upregulation of DR5 expression. The combination of TRAIL and caudatin may be a promising therapeutic approach for the treatment of breast cancer.

Diosgenin-loaded niosome as an effective phytochemical nanocarrier: physicochemical characterization, loading efficiency, and cytotoxicity assay

BACKGROUND

The use of phytochemicals to prevent or suppress tumours is known as chemoprevention. Numerous plant-derived agents have been reported to have anticancer potentials. As one such anticancer phytochemical, diosgenin has several applications which are nevertheless limited due to its low solubility in water.

METHODS

We loaded diosgenin into niosome to increase its solubility and hence efficiency. Diosgenin-niosome (diosgenin loaded into niosome) was prepared by thin-film hydration method and characterised by optical microscopy, dynamic light scattering (DLS), scanning electron microscopy (SEM), and UV-visible spectrophotometry. Also, loading efficiency, in vitro drug release, and cytotoxicity assay were performed on HepG2 cell line.

RESULTS AND DISCUSSION

Diosgenin-niosome has a nanometric size with a normal size distribution and spherical morphology. The loading efficiency of diosgenin was about 89% with a sustainable and controllable release rate. Finally, the viability of free diosgenin was 61.25%, and after loading into niosomes, it was improved to 28.32%.

CONCLUSION

The results demonstrated that niosomes increase the solubility of naturally derived hydrophobic chemicals and thus enhance their anticancer effect. Graphical abstract.

Diosgenin exerts its tumor suppressive function via inhibition of Cdc20 in osteosarcoma cells

Osteosarcoma (OS) is one of the aggressive malignancies for young adults. Cdc20 (cell division cycle 20 homologue) has been reported to exhibit an oncogenic role in OS, suggesting that inhibition of Cdc20 could be a novel strategy for the treatment of OS. Since Cdc20 inhibitors have side effects, it is important to discover the new CDC20 inhibitors with non-toxic nature. In the present study, we determine whether natural agent diosgenin is an inhibitor of Cdc20 in OS cells. We performed MTT, FACS, Wound healing assay, Transwell, Western blotting, transfection assays in our study. We found diosgenin inhibited cell growth and induced apoptosis. Moreover, diosgenin exposure led to inhibition of cell migration and invasion. Notably, diosgenin inhibited the expression of Cdc20 in OS cells. Overexpression of Cdc20 abrogated the inhibition of cell growth and invasion induced by diosgenin. Our data reveal that inhibition of Cdc20 by diosgenin could be helpful for the treatment of patients with OS.

Advances in the antitumor activities and mechanisms of action of steroidal saponins

The steroidal saponins are one of the saponin types that exist in an unbound state and have various pharmacological activities, such as anticancer, anti-inflammatory, antiviral, antibacterial and nerves-calming properties. Cancer is a growing health problem worldwide. Significant progress has been made to understand the antitumor effects of steroidal saponins in recent years. According to reported findings, steroidal saponins exert various antitumor activities, such as inhibiting proliferation, inducing apoptosis and autophagy, and regulating the tumor microenvironment, through multiple related signaling pathways. This article focuses on the advances in domestic and foreign studies on the antitumor activity and mechanism of actions of steroidal saponins in the last five years to provide a scientific basis and research ideas for further development and clinical application of steroidal saponins.

Role of bile acids in colon carcinogenesis

Bile acids (BAs) are cholesterol derivatives synthesized in the liver and then secreted into the intestine for lipid absorption. There are numerous scientific reports describing BAs, especially secondary BAs, as strong carcinogens or promoters of colon cancers. Firstly, BAs act as strong stimulators of colorectal cancer (CRC) initiation by damaging colonic epithelial cells, and inducing reactive oxygen species production, genomic destabilization, apoptosis resistance, and cancer stem cells-like formation. Consequently, BAs promote CRC progression via multiple mechanisms, including inhibiting apoptosis, enhancing cancer cell proliferation, invasion, and angiogenesis. There are diverse signals involved in the carcinogenesis mechanism of BAs, with a major role of epidermal growth factor receptor, and its down-stream signaling, involving mitogen-activated protein kinase, phosphoinositide 3-kinase/Akt, and nuclear factor kappa-light-chain-enhancer of activated B cells. BAs regulate numerous genes including the human leukocyte antigen class I gene, p53, matrix metalloprotease, urokinase plasminogen activator receptor, Cyclin D1, cyclooxygenase-2, interleukin-8, and miRNAs of CRC cells, leading to CRC promotion. These evidence suggests that targeting BAs is an efficacious strategies for CRC prevention and treatment.

Lipocalin 2 inversely regulates TRAIL sensitivity through p38 MAPK-mediated DR5 regulation in colorectal cancer

TNF-related apoptosis-inducing ligand (TRAIL) induces apoptosis through death receptors (DRs)4 and/or 5 expressed on the cell surface. Multiple clinical trials are underway to evaluate the antitumor activity of recombinant human TRAIL and agonistic antibodies to DR4 or DR5. However, their therapeutic potential is limited by the high frequency of cancer resistance. In this study, we provide evidence demonstrating the role of lipocalin 2 (LCN2) in the TRAIL-mediated apoptosis of human colorectal cancer (CRC). By analyzing the mRNA expression data of 71 CRC tissues from patients, we found that DR5 was preferentially expressed in CRC tissues with a low LCN2 expression level compared to tissues with a high LCN2 expression level. Moreover, we analyzed the association between DR5 and LCN2 expression and this analysis revealed that DR5 expression in CRC tended to be inversely associated with LCN2 expression. By contrast, no association was found between the DR4 and LCN2 expression levels. The expression patterns of LCN2 in human CRC cell lines also exhibited an inverse association with DR5 expression. The knockdown of LCN2 by siRNA in the TRAIL‑resistant CRC cells expressing high levels of LCN2 led to a significant increase in TRAIL-induced apoptosis through the upregulation of DR5 protein and mRNA expression. The mechanism through which LCN2 silencing sensitized the CRC cells to TRAIL was dependent on the extrinsic pathway of apoptosis. In addition, we identified that the knockdown of LCN2 enhanced the sensitivity of the cells to TRAIL through the p38 MAPK/CHOP-dependent upregulation of DR5. Taken together, the findings of this study suggest that LCN2 is responsible for TRAIL sensitivity and LCN2 may thus prove to be a promising target protein in DR-targeted CRC therapy.

Pro-Apoptotic and Anti-Cancer Properties of Diosgenin: A Comprehensive and Critical Review

Novel and alternative options are being adopted to combat the initiation and progression of human cancers. One of the approaches is the use of molecules isolated from traditional medicinal herbs, edible dietary plants and seeds that play a pivotal role in the prevention/treatment of cancer, either alone or in combination with existing chemotherapeutic agents. Compounds that modulate these oncogenic processes are potential candidates for cancer therapy and may eventually make it to clinical applications. Diosgenin is a naturally occurring steroidal sapogenin and is one of the major bioactive compounds found in dietary fenugreek (Trigonella foenum-graecum) seeds. In addition to being a lactation aid, diosgenin has been shown to be hypocholesterolemic, gastro- and hepato-protective, anti-oxidant, anti-inflammatory, anti-diabetic, and anti-cancer. Diosgenin has a unique structural similarity to estrogen. Several preclinical studies have reported on the pro-apoptotic and anti-cancer properties of diosgenin against a variety of cancers, both in in vitro and in vivo. Diosgenin has also been reported to reverse multi-drug resistance in cancer cells and sensitize cancer cells to standard chemotherapy. Remarkably, diosgenin has also been reported to be used by pharmaceutical companies to synthesize steroidal drugs. Several novel diosgenin analogs and nano-formulations have been synthesized with improved anti-cancer efficacy and pharmacokinetic profile. In this review we discuss in detail the multifaceted anti-cancer properties of diosgenin that have found application in pharmaceutical, functional food, and cosmetic industries; and the various intracellular molecular targets modulated by diosgenin that abrogate the oncogenic process.

Dual-specificity phosphatase 6 (DUSP6): a review of its molecular characteristics and clinical relevance in cancer

Mitogen-activated protein kinases (MAPKs) are the main regulators of cellular proliferation, growth, and survival in physiological or pathological conditions. Aberrant MAPK signaling plays a pivotal role in carcinogenesis, which leads to development and progression of human cancer. Dual-specificity phosphatase 6 (DUSP6), a member of the MAPK phosphatase family, interacts with specifically targeted extracellular signal-regulated kinase 1/2 via negative feedback regulation in the MAPK pathway of mammalian cells. This phosphatase functions in a dual manner, pro-oncogenic or tumor-suppressive, depending on the type of cancer. To date, the tumor-suppressive role of DUSP6 has been demonstrated in pancreatic cancer, non-small cell lung cancer, esophageal squamous cell and nasopharyngeal carcinoma, and ovarian cancer. Its pro-oncogenic role has been observed in human glioblastoma, thyroid carcinoma, breast cancer, and acute myeloid carcinoma. Both roles of DUSP6 have been documented in malignant melanoma depending on the histological subtype of the cancer. Loss- or gain-of-function effects of DUSP6 in these cancers highlights the significance of this phosphatase in carcinogenesis. Development of methods that use the DUSP6 gene as a therapeutic target for cancer treatment or as a prognostic factor for diagnosis and evaluation of cancer treatment outcome has great potential. This review focuses on molecular characteristics of the DUSP6 gene and its role in cancers in the purview of development, progression, and cancer treatment outcome.

Synthesis of tigogenin MeON-Neoglycosides and their antitumor activity

To discover new potent cytotoxic steroidal saponins, a series of tigogenin neoglycosides were synthesized via oxyamine neoglycosylation for the first time. The preliminary bioassays for their in vitro antitumor activities against five human cancer cell lines (A375, A-549, HCT-116, HepG2 and MCF-7) were conducted. The results revealed a sugar-dependent activity profile of their cytotoxicity, the glycoconjugation converted the non-active tigogenin to the most potential product Tg29 ((3R)-N-methoxyamino-tigogenin-β-2-deoxy-d-galactoside) with IC₅₀ value of 2.7μM and 4.6μM against HepG2 and MCF-7 cells respectively. And the 3R-tigogenin neoglycosides exhibited enhanced antitumor activity while the 3S-tigogenin almost showed no activity. Among the five cell lines, HepG2 and MCF-7 cells showed more sensitive cytotoxic responses to the products. Therefore, the neoglycosylation could be a promising strategy for the synthesis of antitumor steroidal saponins and it also proved the essential role of carbohydrate moiety of steroidal saponins in the biological activity.

Observation of the influences of diosgenin on aging ovarian reserve and function in a mouse model

BACKGROUND

The aim of this study was to investigate the impact of diosgenin, an important monomer of sapogenins in yams, on ovarian reserve in a natural aging mice model.

STUDY DESIGN

This randomized controlled trial included 60 9-month-old C57 naturally aging female mice. Twenty-one mice were assigned to the dio group and were fed a single dose of diosgenin (200 mg/kg/day) suspended in 0.3% CMC. Twenty mice were assigned to the DHEA group and were fed a single dose of DHEA (1.25 mg/kg/day) suspended in 0.3% CMC. The remaining 20 mice were assigned to the old control group and were fed a single dose of 0.3% CMC. Three months later, the reproductive performance of these female mice was determined by evaluating ovarian follicles and oocyte number and quality in IVF and comparing age-matched and young controls. The impact of NOBOX, GDF9 and BMP15 mRNA expression was also evaluated.

RESULTS

Diosgenin improves ovarian reserve in naturally aging mice in terms of increasing the number of primary follicles (P < 0.05) and serum levels of AMH (P < 0.05).

CONCLUSIONS

Diosgenin could counteract age-associated ovarian dysfunction by improving the ovarian reserve in a natural aging mice model.

Anticancer potential of Trigonella foenum graecum: Cellular and molecular targets

A growing body of evidence supported by numerous studies on tumorigenesis confirms that it is possible to target various hallmarks of cancer. Recent studies have shown that plant-derived molecules may be used in targeting different signaling pathways for cancer drug discovery. The present paper gives an insight into the anticancer potential of fenugreek and lists the existing studies that have been carried out to demonstrate the advantages of the use of fenugreek in cancer treatment and prevention. It also aims at opening up new perspectives in the development of new drugs of natural origins in the future clinical trials. This review article will discuss; (1) the chemical constituents and bioactive compounds of fenugreek; (2) effects on oxidative stress and inflammation; (3) effects on proliferation, apoptosis, and invasion; (4) toxicity of fenugreek; and 5) future directions in cancer drug development. All of the experimental studies discussed in this paper suggest that multiple signaling pathways (hallmarks) are involved in the anticancer activities of fenugreek, but their efficacy is still unclear, which requires further investigation.