Chloroform extract of Citrus unshiu Markovich peel induces apoptosis and inhibits stemness in HeLa human cervical cancer cells.

Cervical cancer is the second most common cancer among women worldwide. However, chemotherapies for this cancer often cause many side effects and chemoresistance. Citrus unshiu Markovich peel (CECU) has been used as a traditional medicine for the treatment of various diseases in East Asia. Recently, the anticancer activities and mechanisms of action of CECU extract have been reported in a number of different cancer cell types, but no study has evaluated the therapeutic effect of this natural product on cervical cancer cells. In the current study, the anticancer activity and the underlying molecular mechanism of the chloroform extract of CECU was investigated on HeLa human cervical cancer cells. The results showed that CECU effectively inhibited the proliferation and migration of HeLa cells. Treatment of cells with CECU led to cell cycle arrest at the G2/M phase and activation of extrinsic and intrinsic apoptotic pathways. Furthermore, the proliferation inhibitory effect of CECU was due to the inactivation of AKT and ERK signaling, upregulation of p53 and p21, and downregulation of cyclin B1 and cyclin D1, but not reactive oxygen species (ROS) generation. Furthermore, CECU inhibited the stem­like features of HeLa cells by downregulating key cancer stemness biomarkers. Therefore, CECU may be an effective complementary and alternative medicine for the prevention and treatment of cervical cancer.

Sparassis crispa exerts anti-inflammatory activity via suppression of TLR-mediated NF-κB and MAPK signaling pathways in LPS-induced RAW264.7 macrophage cells.

ETHNOPHARMACOLOGY RELEVANCE: Sparassis crispa, also known as cauliflower mushroom, has been used historically in traditional Asian medicine. It possesses various biological activities, such as immunopotentiation, anti-diabetes, anti-cancer, and anti-inflammatory effects. Recently, we isolated the non-aqueous fraction from methanol extract of S. crispa (SCF4) by using water-organic solvent mixtures and high-performance liquid chromatography (HPLC). In the present study, we identified the anti-inflammatory activity and action mechanism of SCF4 in lipopolysaccharide (LPS)-stimulated RAW264.7 murine macrophage cells. MATERIALS AND METHODS: The chloroform layer isolated from S. crispa methanol extract was separated into seven fractions using preparative HPLC. The fractions were then applied to NO assay to identify the fraction with the best anti-inflammatory activity. The inflammation inhibitory effect and underlying mechanism of SCF4 in LPS-stimulated RAW264.7 cells were assessed using WST-1 assay, enzyme-linked immunosorbent assay (ELISA), ROS assay, and Western blot analysis. RESULTS: SCF4 significantly suppressed LPS-induced production of pro-inflammatory mediators, such as nitric oxide (NO) and prostaglandin E2 (PGE2), and pro-inflammatory cytokines, including tumor necrosis factor (TNF)-α, interleukin (IL)- 6, and IL-1ß, without cytotoxicity. In addition, SCF4 downregulated not only the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), but also the activation of nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) stimulated by LPS. SCF4 also blocked the nuclear translocation of NF-κB via reduction of inhibitor of κB alpha (IκBα) degradation. Furthermore, SCF4 inhibited the phosphorylation of transforming growth factor beta-activated kinase 1 (TAK1), an important upstream factor of NF-κB and MAPK signaling mediated through toll-like receptor (TLR). CONCLUSIONS: These findings demonstrate for the first time the correlation between the anti-inflammatory activity of SCF4 and TLR-mediated NF-κB and MAPK signaling pathways in LPS-stimulated RAW264.7 macrophage cells, suggesting that the non-aqueous extract of S. crispa could be applied as a promising natural product for the prevention and treatment of inflammatory diseases.

Hovenia dulcis Thunb. and its active compound ampelopsin inhibit angiogenesis through suppression of VEGFR2 signaling and HIF-1α expression.

Specific inhibition of angiogenesis has been considered a powerful strategy for the treatment of cancer and other angiogenesis-related human diseases. Hovenia dulcis Thunb., Japanese raisin tree or Oriental raisin tree, is a hardy tree found in Asia, Eastern China and Korea and has been known to possess various biological activities, including antifatigue, antidiabetic, neuroprotective and hepatoprotective activity. In the present study, for the first time, we evaluated whether a 100% ethanol extract of Hovenia dulcis Thunb. (HDT) inhibits the angiogenesis of human umbilical vein endothelial cells (HUVECs) using in vitro angiogenesis assays. HDT suppressed vascular endothelial growth factor (VEGF)-induced proliferation, migration, invasion and tube formation of HUVECs at subtoxic doses. In addition, HDT significantly inhibited in vivo angiogenesis of the chorioallantoic membrane from growing chick embryos without exhibiting cytotoxicity. Furthermore, HDT downregulated not only VEGF receptor 2 (VEGFR2) signaling in HUVECs, but also hypoxia-inducible factor (HIF)-1α expression in hepatocarcinoma cell line HepG2. Ampelopsin is a bioactive flavanonol found in Hovenia dulcis Thunb. Our data showed that ampelopsin inhibited angiogenesis with no cytotoxicity by suppressing both VEGFR2 signaling and HIF-1α expression. These results suggest that Hovenia dulcis Thunb. and its active compound ampelopsin exhibit potent antiangiogenic activities and therefore could be valuable for the prevention and treatment of angiogenesis-related diseases including cancer.

Apigenin Inhibits Cancer Stem Cell-Like Phenotypes in Human Glioblastoma Cells via Suppression of c-Met Signaling.

Glioblastoma (GBM) is a highly malignant human brain tumor with limited treatment choices. The extremely aggressive characteristics of GBM result from GBM stem cells (GSCs), a subpopulation in tumor having self-renewal potential and resistance to chemotherapy and radiotherapy. Therefore, eliminating GSCs is an effective strategy to treat this fatal disease. In this study, we investigated the therapeutic effects of dietary flavonoids, including apigenin, quercetin, and naringenin, against cancer stem cell-like phenotypes of human GBM cell lines U87MG and U373MG. Among flavonoids studied, apigenin and quercetin significantly suppressed not only the self-renewal capacity such as cell growth and clonogenicity, but also the invasiveness of GBM stem-like cells. Notably, apigenin blocked the phosphorylation of c-Met and its downstream effectors, transducer and activator of transcription 3, AKT (Protein kinase B), and mitogen-activated protein kinase in the GSCs, thereby reducing the expression levels of GSC markers such as CD133, Nanog, and Sox2. These results suggest that the GSC inhibition effect of apigenin may be caused by downregulation of c-Met signaling pathway.

Glycosylation and subsequent malonylation of isoflavonoids in E. coli: strain development, production and insights into future metabolic perspectives.

Genistin and daidzein exhibit a protective effect on DNA damage and inhibit cell proliferation. Glycosylation and malonylation of the compounds increase water solubility and stability. Constructed pET15b-GmIF7GT and pET28a-GmIF7MAT were used for the transformation of Escherichia coli and bioconversion of genistein and daidzein. To increase the availability of malonyl-CoA, a critical precursor of GmIF7MAT, genes for the acyl-CoA carboxylase α and ß subunits (nfa9890 and nfa9940), biotin ligase (nfa9950), and acetyl-CoA synthetase (nfa3550) from Nocardia farcinia were also introduced. Thus, the isoflavonoids were glycosylated at position 7 by 7-O-glycosyltranferase and were further malonylated at position 6(″) of glucose by malonyl-CoA: isoflavone 7-O-glucoside-6(″)-O-malonyltransferase both from Glycine max. Engineered E. coli produced 175.7 µM (75.90 mg/L) of genistin and 14.2 µM (7.37 mg/L) genistin 6''-O-malonate. Similar conditions produced 162.2 µM (67.65 mg/L) daidzin and 12.4 µM (6.23 mg/L) daidzin 6''-O-malonate when 200 µM of each substrate was supplemented in the culture. Based on our findings, we speculate that isoflavonoids and their glycosides may prove useful as anticancer drugs with added advantage of increased solubility, stability and bioavailability.

Matairesinol inhibits angiogenesis via suppression of mitochondrial reactive oxygen species.

Mitochondrial reactive oxygen species (mROS) are involved in cancer initiation and progression and function as signaling molecules in many aspects of hypoxia and growth factor-mediated signaling. Here we report that matairesinol, a natural small molecule identified from the cell-based screening of 200 natural plants, suppresses mROS generation resulting in anti-angiogenic activity. A non-toxic concentration of matairesinol inhibited the proliferation of human umbilical vein endothelial cells. The compound also suppressed in vitro angiogenesis of tube formation and chemoinvasion, as well as in vivo angiogenesis of the chorioallantoic membrane at non-toxic doses. Furthermore, matairesinol decreased hypoxia-inducible factor-1α in hypoxic HeLa cells. These results demonstrate that matairesinol could function as a novel angiogenesis inhibitor by suppressing mROS signaling.

A novel Ca2+/calmodulin antagonist HBC inhibits angiogenesis and down-regulates hypoxia-inducible factor.

Recent reports have shown that Ca(2+)/calmodulin (Ca(2+)/CaM) signaling plays a crucial role in angiogenesis. We previously developed a new Ca(2+)/CaM antagonist, HBC (4-{3,5-bis-[2-(4-hydroxy-3-methoxyphenyl)ethyl]-4,5-dihydropyrazol-1-yl}benzoic acid), from a curcumin-based synthetic chemical library. Here, we investigated its anti-angiogenic activity and mode of action. HBC potently inhibited the proliferation of human umbilical vascular endothelial cells with no cytotoxicity. Furthermore, HBC blocked in vitro characteristics of angiogenesis such as tube formation and chemoinvasion, as well as neovascularization of the chorioallantoic membrane of growing chick embryos in vivo. Notably, HBC markedly inhibited expression of hypoxia-inducible factor-1alpha (HIF-1alpha) at the translational level during hypoxia, thereby reducing HIF-1 transcriptional activity and expression of its major target gene, vascular endothelial growth factor. In addition, combination treatment with HBC and various HIF-1 inhibitors, including suberoylanilide hydroxamic acid, rapamycin, and terpestacin, had greater anti-angiogenic activity than treatment with each single agent. Collectively, our findings indicate that HBC is a new anti-angiogenic agent targeting HIF that can be used to explore the biological role of Ca(2+)/CaM in angiogenesis.

Atypical takotsubo cardiomyopathy associated with nasal packing for paranasal sinus surgery.

Takotsubo cardiomyopathy (TC) is characterized by reversible left ventricular (LV) apical ballooning and no significant coronary artery stenosis. New variants of TC with localized wall motion abnormality or inversed pattern with hyperdynamic apex have been reported. We present the case of a 24-year-old female with atypical presentation of TC occurring in the setting of paranasal sinus surgery under local anaesthesia with post-surgical nasal packing. She did not demonstrate ST-segment elevation on electrocardiogram, but transient moderate LV systolic dysfunction and localized wall motion abnormality affecting basal to mid-ventricular anterior and anteroseptal wall. She rapidly and completely recovered without sequelae.

Cryptotanshinone but not tanshinone IIA inhibits angiogenesisin vitro.

In the course of screening of angiogenesis inhibitor from natural products, cryptotanshinone from Salvia miltiorrhiza was isolated as a potent small molecule inhibitor of angiogenesis. Cryptotanshinone inhibits bFGF-induced angiogenesis of BAECs at ten micromolar ranges in vitro without cytotoxicity. Tanshinone IIA, another tanshinone isolated from S. miltiorrhiza, which is structurally very similar to cryptotanshinone except C-15 position of dihydrofuran ring does not inhibit angiogenesis induced by bFGF. These results demonstrate that cryptotanshinone is a new anti-angiogenic agent and double bond at C-15 position of the dihydrofuran ring plays a crucial role in the activity.