Telomerase-associated apoptotic events by mushroom ganoderma lucidum on premalignant human urothelial cells

The chemopreventive effects of Ganoderma lucidum was tested, using a tumorigenic transformable human urothelial cell (HUC-PC) model. These in vitro data show that G. lucidum can inhibit the viability and growth of HUC-PC. This could be explained by a concomitant induction of apoptosis and inhibition of telomerase activity. Significant exteriorization of phosphatidylserine was detected by Annexin-V on cell surface, and the cells subsequently lost membrane integrity for uptake of 7-amino-actinomycin D dye. Additionally, the levels of hydrogen peroxide and 8-hydroxy-2'-deoxyguanosine (8-OHdG) production of the apoptotic cells were significantly increased. The induction of apoptosis and suppression of telomerase activity help to explain the anti-HUC-PC growth properties; however, the induction of oxidative stress requires further study. This study strongly suggests that G. lucidum is a potential source of chemopreventive agents for bladder cancer based on its effectiveness in controlling the premalignant urothelial cell growth and carcinogen-induced transformation.     

Triterpenes From Ganoderma Lucidum Induce Autophagy in Colon Cancer Through the Inhibition of p38 Mitogen-Activated Kinase (p38 MAPK)

Medicinal mushroom Ganoderma lucidum is one of the most esteemed natural products that have been used in the traditional Chinese medicine. In this article, we demonstrate that G. lucidum triterpene extract (GLT) suppresses proliferation of human colon cancer cells HT-29 and inhibits tumor growth in a xenograft model of colon cancer. These effects of GLT are associated with the cell cycle arrest at G0/G1 and the induction of the programmed cell death Type II–autophagy in colon cancer cells. Here, we show that GLT induces formation of autophagic vacuoles and upregulates expression of Beclin-1 (1.3-fold increase) and LC-3 (7.3-fold increase) proteins in colon cancer cells and in tumors in a xenograft model (Beclin-1, 3.9-fold increase; LC-3, 1.9-fold increase). Autophagy is mediated through the inhibition of p38 mitogen-activated protein kinase (p38 MAPK) because p38 MAPK inhibitor, SB202190, induces autophagy and expression of Beclin-1 (1.2-fold increase) and LC-3 (7.4-fold increase), and GLT suppresses phosphorylation of p38 MAPK (≈60% inhibition) in colon cancer cells. Taken together, our data demonstrate a novel mechanism responsible for the inhibition of colon cancer cells by G. lucidum and suggest GLT as natural product for the treatment of colon cancer.     

Cancer Chemopreventive,Antiproliferative, and Superoxide Anion Scavenging Properties of Kluyveromyces marxianus and Saccharomyces cerevisiae var. boulardii Cell Wall Components

This study investigated the cancer chemopreventive, the antiradical, and the antiproliferative properties of polysaccharides extracts from cell wall of Saccharomyces boulardii and Kluyveromyces marxianus. β-glucan, mannan, and chitin were also quantified to identify the most important extract responsible for these biological properties. Soluble and insoluble glucans as well as mannoprotein were extracted from cell wall using single hot-alkaline method. Superoxide anion scavenging (antiradical capacity), NAD(P)H: quinone reductase (QR) (EC 1.6.99.2) induction, and antiproliferative assays were done for the evaluation of biological properties of those extracts. The insoluble glucan from S. boulardii revealed the most relevant biological properties by increasing QR activity and exhibiting the highest growth inhibition against colorectal cancer cells. Moreover, high amount of glucan, high glucan/total sugars ratios, and low chitin/glucan ratios were shown to have an impact on enhancing cancer chemopreventive and antiproliferative properties. To our knowledge, this is the first study that demonstrates QR activity by yeast cell wall components in a dose-dependent manner.     

A detailed comparative study between chemical and bioactive properties of Ganoderma lucidum from different origins

A detailed comparative study on chemical and bioactive properties of wild and cultivated Ganoderma lucidum from Serbia (GS) and China (GCN) was performed. This species was chosen because of its worldwide use as medicinal mushroom. Higher amounts of sugars were found in GS, while higher amounts of organic acids were recorded in GCN. Unsaturated fatty acids predominated over saturated fatty acids. GCN revealed higher antioxidant activity, while GS exhibited inhibitory potential against human breast and cervical carcinoma cell lines. No cytotoxicity in non-tumour liver primary cell culture was observed for the different samples. Both samples possessed antibacterial and antifungal activities, in some cases even better than the standard antimicrobial drugs. This is the first study reporting a comparison of chemical compounds and bioactivity of G. lucidum samples from different origins.     

Anticancer Properties of Ganoderma Lucidum Methanol Extracts In Vitro and In Vivo

Anticancer activities of various extracts of the medicinal mushroom, Ganoderma lucidum, have been widely demonstrated and are mainly associated with the presence of different bioactive polysaccharides and triterpenoids. We have evaluated and compared in vitro and in vivo the antitumor effects of two preparations from Ganoderma lucidum: a methanol extract containing total terpenoids (GLme) and a purified methanol extract containing mainly acidic terpenoids (GLpme). Both extracts inhibited tumor growth of B16 mouse melanoma cells inoculated subcutaneously into syngeneic C57BL/6 mice and reduced viability of B16 cells in vitro, whereby GLme exhibited stronger effect. Furthermore, anticancer activity of GLme was demonstrated for the first time against two other rodent tumor cell lines, L929-mouse fibrosarcoma and C6-rat astrocytoma. The mechanism of antitumor activity of GLme comprised inhibition of cell proliferation and induction of caspase-dependent apoptotic cell death mediated by upregulated p53 and inhibited Bcl-2 expression. Moreover, the antitumor effect of the GLme was associated with intensified production of reactive oxygen species, whereas their neutralization by the antioxidant, N-acetyl cysteine, resulted in partial recovery of cell viability. Thus, our results suggest that GLme might be a good candidate for treatment of diverse forms of cancers.     

Sporoderm-Broken Spores of Ganoderma lucidum Inhibit the Growth of Lung Cancer: Involvement of the Akt/mTOR Signaling Pathway

The sporoderm-broken spores of Ganoderma lucidum (SBGS) and their extracts exhibited a wide range of biological activities. In the present study, we prepare ethanol/ethanol extract (E/E-SBGS) and ethanol/aqueous extract (E/A-SBGS) from SBGS and examine their antitumor activities against human lung cancer. Our results showed that E/E-SBGS, not E/A-SBGS, inhibited the survival and migration of lung cancer cells in a dose-dependent manner. E/E-SBGS arrested cell cycle at G2/M phase and triggered apoptosis by decreasing the expression and activity of cell cycle regulators, cyclin B1 and cdc2, as well as anti-apoptotic proteins, Bcl-2 and Bcl-xl. Consequently, colony formation of lung cancer cells was markedly blocked by E/E-SBGS at subtoxic concentrations. Oral administration of both E/E-SBGS and SBGS significantly suppressed tumor volume and tumor weight without gross toxicity in mice. Mechanism study showed that E/E-SBGS dose-dependently suppressed the activation of Akt, the mammalian target of rapamycin (mTOR) and their downstream molecules S6 kinase and 4E-BP1 in treated tumor cells. Taken together, these results indicate that the ethanol extract of sporoderm-broken spores of G. lucidum suppresses the growth of human lung cancer, at least in part, through inhibition of the Akt/mTOR signaling pathway, suggesting its potential role in cancer treatments.     

Antiproliferative and Proapoptotic Effects of Viable or Heat-Killed Lactobacillus paracasei IMPC2.1 and Lactobacillus rhamnosus GG in HGC-27 Gastric and DLD-1 Colon Cell Lines

Data from literature suggest the possible use of probiotics as chemopreventive agents against colon cancer, but few investigations are available on their effects on gastric cancer proliferation. In our previous study, a specific Lactobacillus, strain L. paracasei IMPC2.1, was demonstrated to colonize the human gut and positively affect fecal bacteria and biochemical parameters. The aims of the present study were to investigate the effects of L. paracasei IMPC2.1, comparing them with those of Lactobacillus rhamnosus GG (L.GG), either as viable or heat-killed cells, on cell proliferation and apoptosis in a gastric cancer (HGC-27) and a colorectal cancer cell line (DLD-1). Both the gastric and colon cancer cells were sensitive to the growth inhibition and apoptosis induction by both viable or heat-killed cells from L. paracasei IMPC2.1 and L.GG. These findings suggest the possibility for a food supplement, based on dead probiotics, including L. paracasei IMPC2.1 cells, which could represent an effective component of a functional food strategy for cancer growth inhibition, with potential for cancer prevention.     

Chemopreventive effects of raw and roasted oat flakes after in vitro fermentation with human faecal microbiota

Abstract

The aim of the present study was to analyse chemopreventive effects of oat flakes under consideration of processing. Thin and thick flakes were roasted and subjected to an in vitro digestion and fermentation. Fermentation supernatants (FS) were characterised and chemopreventive effects were analysed in LT97 colon adenoma cells. Compared to the fermentation control, pH values were decreased (from pH 6.3 to pH 5.0) and concentrations of SCFA, in particular butyrate, were increased in oat FS (2.6-fold, on average). Ammonia levels were not altered. Oat FS significantly decreased cell growth time- and dose-dependently. Caspase 3 activity was significantly increased (9.7-fold, on average). Oat FS slightly increased the mRNA expression of CAT (2.0-fold), SOD2 (1.7-fold) and GSTP1 (2.8-fold), on average, while GPX1 mRNA (0.3-fold) was decreased. The results indicate a chemopreventive potential of in vitro digested oat flakes regarding colon cancer development mediated mostly by growth inhibition and apoptosis, unaffected by roasting.     

A Comparative Study on Immunomodulatory Activity of Polysaccharides from Two Official Species of Ganoderma (Lingzhi)

Two Ganoderma species, G. lucidum and G. sinense, are listed as Lingzhi in Chinese Pharmacopoeia and they are considered to have the same therapeutic effects. Polysaccharides were the main immunomodulatory and anticancer components in Ganoderma. In this study, the chemical characters and the effects of polysaccharides from G. lucidum (GLPS) and G. sinense (GSPS) on macrophage functions were investigated and compared. Chemical studies showed that GLPS and GSPS were different, displaying various molecular weight distribution and ratio of monosaccharide components. In vitro pharmacological studies showed that both GLPS and GSPS had potent effects on macrophage functions, such as promoting macrophage phagocytosis, increasing their release of nitric oxide and cytokines interleukin (IL)-1α, IL-6, IL-10, and tumor necrosis factor-α. Generally, GLPS was more powerful than GSPS. This study is helpful to elucidate the active components and pharmacological variation between the 2 Ganoderma species. The structure-activity relationship of polysaccharides from Ganoderma needs further study.     

Inhibitory Kinetics and Mechanism of Flavonoids Extracted from Cotinus coggygria Scop. Against Glioblastoma Cancer

This proposal seeks to study the potential therapeutic modality of chemoprevention and anticancer effects and mechanisms of the flavonoids from Cotinus coggygria Scop. on glioblastoma cancer. In the current study, the total flavonoids (TFs) isolated from Cotinus coggygria Scop. var. cinerea Engl. (Cotinus coggygria Scop.) and the major flavonoids of Cotinus coggygria Scop. (CCFs) were identified, and the inhibitory kinetics of TF and CCF on glioblastoma cell lines were calculated. We also investigated whether TF or CCF regulated the apoptotic mechanism in cellular models of glio-blastoma cells. Finally, we evaluated whether treatment with TF or CCF suppressed tumor growth and inhibited migration in orthotopic mouse models of glioblastoma in vivo. In this study, the CCFs were identified as rutin, myricetin, and fisetin. TF and CCF remarkably inhibited cell proliferation and downregulated the PI3K/Akt and ERK signaling pathway in glioblastoma cell lines. Furthermore, the mitochondrial caspase-dependent cascade was regulated by TF and myricetin. In addition, TF and myricetin exhibited significant antitumor effects on glioblastoma in vivo. Taken together, these results suggest that phytochemical and biological data provide evidence for the active components in Cotinus coggygria, and that the TFs are responsible for the anticancer effects on glioblastoma cell growth via induction of apoptosis. In addition, the representative compound myricetin could provide a clinically relevant therapeutic opportunity. Therefore, our data strongly suggest that myricetin-deprived CCF can serve as a potent chemopreventive herbal medicine.     

Docosahexaenoic Acid Induces Growth Suppression on Epithelial Ovarian Cancer Cells More Effectively than Eicosapentaenoic Acid

Omega-3 fatty acids, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have been shown to possess definitively suppressive effects on the growth of epithelial ovarian cancer cells. This study investigated the differential effects of pure EPA and DHA on the growth of epithelial ovarian cancer cells and the potential molecular mechanisms that may be involved. There were significant time- and dose-dependent inhibitory effects of both EPA and DHA on cellular proliferation of the epithelial ovarian cancer cell line TOV-21G (P < 0.05). TOV-21G cells pretreated with peroxisome proliferator receptor activator gamma (PPARγ) antagonist, GW9662, markedly suppressed EPA/DHA-induced apoptosis as determined by TUNEL assay, Annexin V-FITC/PI staining, and caspase-3 activity. EPA/DHA significantly induced PPARγ and p53 overexpression as observed in immunoblotting assay and the induction of p53 by EPA/DHA was abolished by GW9662. In all cases, the effect of DHA was significantly more potent than that of EPA (P < 0.05). Our findings suggested that DHA may be more effective than EPA in growth suppression of TOV-21G cells and the biologic effects may be partly mediated by PPARγ and p53 activation. Further research is required to elucidate additional divergent mechanisms to account for apparent differences between EPA and DHA.     

Andrographolide Exhibits Anticancer Potential Against Human Colon Cancer Cells by Inducing Cell Cycle Arrest and Programmed Cell Death via Augmentation of Intracellular Reactive Oxygen Species Level

Andrographolide, a diterpenoid lactone and a major constituent of Andrographis paniculata Nees, exhibits remarkable anticancer activity. However, the effect of andrographolide on colon cancer has not been completely elucidated yet. Thus, we investigated the chemopreventive potential of andrographolide in colon cancer HT-29 cells. The cytotoxic potential of andrographolide on HT-29 cells was determined by MTT assay, trypan blue exclusion assay, colony formation assay, and morphological analysis; and apoptotic property by DAPI and Hoechst staining, FITC-Annexin V assay, DNA fragmentation assay and caspase-3 activity assay. To elucidate andrographolide action, intracellular reactive oxygen species (ROS) level was determined by DCFDA dye; change in mitochondrial potential by Rhodamine123 and Mito Tracker Red CMXRos dye; and cell cycle modulatory property by flow cytometric analysis. Results of the study have shown that andrographolide decreased cell viability of HT-29 cells in a dose- and time-dependent manner. Furthermore, andrographolide induced apoptosis in HT-29 cells which seemed to be linked with augmented intracellular ROS level and disruption of mitochondrial membrane potential. Interestingly, andrographolide caused significant cell cycle arrest in G2/M phase at lower doses, but, in G0/G1 phase at higher doses. In summary, our results indicated that andrographolide exhibited antiproliferative and apoptotic properties against colon cancer HT-29 cells.     

姜黄素对人喉癌细胞株Hep-2增殖和端粒酶活性的影响

目的研究姜黄素（curcumin）对人喉癌细胞Hep-2增殖和端粒酶活性表达水平的影响。方法CCK-8法检测不同浓度姜黄素作用于Hep-2后24h、48h、72h的细胞增殖活性：集落形成试验检测不同浓度姜黄素作用于Hep-2后的细胞增殖抑制率;StretchPCR-银染法检测细胞端粒酶活性变化。RT—PCR分析端粒酶主要组分hTERT的mRNA表达情况。结果①姜黄素对Hep-2细胞的增殖抑制作用具有时间和剂量依赖性。五种浓度（20μmol／L、40μmol／L、60μol／L、80μmol／L、100μol／L）姜黄素作用12、24、48、72小时后,IC50分别为81．17μmol／L、40．90μmol／L、33．26μmol／L、31．63μmol／L;②四种浓度（20μmol／L、40μmol／L、60μmol／L、80μmol／L）姜黄素作用于Hep-2细胞48h,-周后各组Hep-2细胞集落形成数和细胞增殖抑制率均呈浓度依赖性．其细胞增殖抑制率与对照组相比,分别为36．25％、57．4％、98．48％、100％;③60μmol／L姜黄素作用于Hep-2细胞24、48、72小时后。与对照组相比,端粒酶活性总光密度值（IOD）分别下降23．19％、60．28％和70．15％,各时间组间有显著性差异（P〈0．01）;端粒酶逆转录酶（hTERT）mRNA表达水平IOD值分别下降2．90％、58．69％和88．35％,各时间组间有显著性差异（P〈o．01）。结论姜黄素可抑制体外培养的Hep-2细胞的增殖活性,下调hTERTmR．NA的转录水平并抑制细胞的端粒酶活性,有较好的临床应用前景。