Thioacetamide-Induced Norepinephrine Production by Hepatocytes is Associated with Hepatic Stellate Cell Activation and Liver Fibrosis.

Background: Collagen production by activated hepatic stellate cells (HSCs) to encapsulate injury is part of the natural wound-healing response in injured liver. However, persistent activation of HSCs can lead to pathological fibrogenesis. Such persistent HSC activation could be mediated by norepinephrine (NE), a reaction product of dopamine beta-hydroxylase (DBH).

Colossolactone H, a new Ganoderma triterpenoid exhibits cytotoxicity and potentiates drug efficacy of gefitinib in lung cancer.

Three pentacyclic triterpene dilactones were isolated from the fruiting bodies of Ganoderma colossum, a medicinal mushroom. Colossolactone H (colo H) as a new compound and the most cytotoxic among the isolates was studied for its anticancer mechanism and the potential use in cancer therapy. Gene expression profiling analysis indicated that treatment of lung cancer cells with colo H caused upregulation of 252 genes and downregulation of 398 genes.

GPKOW is essential for pre-mRNA splicing in vitro and suppresses splicing defect caused by dominant-negative DHX16 mutation in vivo.

Human GPKOW [G-patch (glycine-rich) domain and KOW (Kyrpides, Ouzounis and Woese) domain] protein contains a G-patch domain and two KOW domains, and is a homologue of Arabidopsis MOS2 and Saccharomyces Spp2 protein. GPKOW is found in the human spliceosome, but its role in pre-mRNA splicing remains to be elucidated. In this report, we showed that GPKOW interacted directly with the DHX16/hPRP2 and with RNA.

The antileukemia activity of natural product HQ17(3) is possibly associated with downregulation of miR-17-92 cluster.

The compound 10'(Z),13'(E),15'(E)-heptadecatrienylhydroquinone [HQ17(3)] was purified from the sap of the lacquer tree Rhus succedanea. HQ17(3) has cytotoxic effect on cancer cells and can inhibit topoisomerase (topo) IIα activity. We treated various cancer cells with different doses of HQ17(3) and found that leukemia cells were most sensitive to HQ17(3).

A cysteine-reactive alkyl hydroquinone modifies topoisomerase IIα, enhances DNA breakage, and induces apoptosis in cancer cells.

We previously reported that the anticancer activity of a botanical compound 10'(Z),13'(E),15'(E)-heptadecatrienylhydroquinone [HQ17(3)] was attributed to topoisomerase (Topo) IIα poisoning and the induction of oxidative damage. HQ17(3) irreversibly inhibits Topo IIα activity in vitro and is more cytotoxic in leukemia HL-60 cells than in Topo IIα-deficient variant HL-60/MX2 cells, which suggests that Topo IIα is a cellular target of HQ17(3). This study further characterizes the molecular mechanisms of the anticancer activity of HQ17(3).

10'(Z),13'(E)-heptadecadienylhydroquinone inhibits swarming and virulence factors and increases polymyxin B susceptibility in Proteus mirabilis.

In this study, we demonstrated that 10'(Z), 13'(E)-heptadecadienylhydroquinone (HQ17-2), isolated from the lacquer tree, could decrease swarming motility and hemolysin activity but increase polymyxin B (PB) susceptibilityof Proteus mirabilis which is intrinsically highly-resistant to PB. The increased PB susceptibility induced by HQ17-2 was also observed in clinical isolates and biofilm-grown cells. HQ17-2 could inhibit swarming in the wild-type and rppA mutant but not in the rcsB mutant, indicating that HQ17-2 inhibits swarming through the RcsB-dependent pathway, a two-component signaling pathway negatively regulating swarming and virulence factor expression.

ALDH-positive lung cancer stem cells confer resistance to epidermal growth factor receptor tyrosine kinase inhibitors.

Molecular targeting therapeutics, such as EGFR tyrosine kinase inhibitors (TKIs), are important treatment strategies for lung cancer. Currently, the major challenge confronting targeted cancer therapies is the development of resistance. Cancer stem cells (CSCs) represent a rare population of undifferentiated tumorigenic cells responsible for tumor initiation, maintenance and spreading.

Arachidin-1, a peanut stilbenoid, induces programmed cell death in human leukemia HL-60 cells.

The stilbenoids, arachidin-1 (Ara-1), arachidin-3, isopentadienylresveratrol, and resveratrol, have been isolated from germinating peanut kernels and characterized as antioxidant and anti-inflammatory agents. Resveratrol possesses anticancer activity, and studies have indicated that it induces programmed cell death (PCD) in human leukemia HL-60 cells. In this study, the anticancer activity of these stilbenoids was determined in HL-60 cells.

Slug confers resistance to the epidermal growth factor receptor tyrosine kinase inhibitor.

Rationale: Non-small cell lung cancers carrying epidermal growth factor receptor (EGFR) mutations respond well to EGFR tyrosine kinase inhibitors (TKIs), but patients ultimately develop drug resistance and relapse. Although epithelial-mesenchymal transition (EMT) can predict resistance to EGFR TKIs, the molecular mechanisms are still unknown.

Objectives: To examine the role of EMT regulators in resistance to gefitinib.

Nuclear retention of unspliced pre-mRNAs by mutant DHX16/hPRP2, a spliceosomal DEAH-box protein.

Defective or imbalanced expression of spliceosomal factors has been linked to human disease; however, how a defective spliceosome affects intron-containing gene transcripts in human cells is largely unknown. DEAH-box protein DHX16 is a human orthologue of Saccharomyces cerevisiae spliceosomal protein Prp2, an RNA-dependent ATPase that activates the spliceosome before the first catalytic step of splicing. Yeast prp2 mutants accumulate unspliced RNAs from the vast majority of intron-containing genes.

Endonuclease V-mediated deoxyinosine excision repair in vitro.

Deoxyinosine (dI) in DNA can arise from hydrolytic or nitrosative deamination of deoxyadenosine. It is excised in a repair pathway that is initiated by endonuclease V, the nfi gene product, in Escherichia coli. Repair was studied in vitro using M13mp18 derived heteroduplexes containing a site-specific deoxyinosine.

Identification of an Alkylhydroquinone from Rhus succedanea as an Inhibitor of Tyrosinase and Melanogenesis.

The alkylhydroquinone 10'(Z)-heptadecenylhydroquinone [HQ17(1)], isolated from the sap of the lacquer tree Rhus succedanea, was found to inhibit the activity of tyrosinase and to suppress melanin production in animal cells. The IC50 of HQ17(1) as a tyrosinase inhibitor was 37 microM versus 70 microM for hydroquinone (HQ), a known inhibitor of tyrosinase and melanogenesis. For the inhibition of melanin production in mouse B16 melanoma cells, the EC50 of HQ17(1) was 40 microM versus 124 microM for HQ.

Proteomics integrated with Escherichia coli vector-based vaccines and antigen microarrays reveals the immunogenicity of a surface sialidase-like protein of Propionibacterium acnes.

Proteomics is a powerful tool for the identification of proteins, which provides a basis for rational vaccine design. However, it is still a highly technical and time-consuming task to examine a protein's immunogenicity utilizing traditional approaches. Here, we present a platform for effectively evaluating protein immunogenicity and antibody detection.

Anticancer activity of botanical alkyl hydroquinones attributed to topoisomerase II poisoning.

Cytotoxic alkyl hydroquinone compounds have been isolated from many plants. We previously isolated 3 structurally similar cytotoxic alkyl hydroquinone compounds from the sap of the lacquer tree Rhus succedanea L. belonging to the sumac family, which have a long history of medicinal use in Asia.

A novel immunogenic spore coat-associated protein in Bacillus anthracis: characterization via proteomics approaches and a vector-based vaccine system.

New generation anthrax vaccines have been actively explored with the aim of enhancing efficacies and decreasing undesirable side effects that could be caused by licensed vaccines. Targeting novel antigens and/or eliminating the requirements for multiple needle injections and adjuvants are major objectives in the development of new anthrax vaccines. Using proteomics approaches, we identified a spore coat-associated protein (SCAP) in Bacillus anthracis.

Specific stabilization of DNA triple helices by indolo[2,1-b]quinazolin-6,12-dione derivatives.

Derivatives of indolo[2,1-b]quinazolinone containing aminoalkylamino side chains were synthesized as specific DNA triplex stabilizing agents. The aminoalkylamino side chains are essential for triplex stabilization. The position-8 fluorine atom or a methyl group to the nitrogen adjacent to the planar core can enhance triplex stability by 6 degrees C and the effect is additive.

Inhibition of swarming and virulence factor expression in Proteus mirabilis by resveratrol.

Resveratrol (3,5,4-trihydroxy-trans-stilbene) is a phytoalexin compound with anti-inflammatory and antioxidant activities. The effect of resveratrol on swarming and virulence factor expression of Proteus mirabilis, an important pathogen infecting the urinary tract, was determined on swarming agar plates with and without the compound. Bacteria harvested at different times were assayed for cell length and the production of flagella, haemolysin and urease.

Ganoderiol F, a ganoderma triterpene, induces senescence in hepatoma HepG2 cells.

Ganoderiol F (GolF), a tetracyclic triterpene, was isolated from Ganoderma amboinense and found to induce senescence of cancer cell lines. GolF induced growth arrest of cancer cell lines HepG2, Huh7 and K562, but exerted much less effect in hepatoma Hep3B cells and normal lung fibroblast MRC5 cells, and no effect on peripheral blood mononuclear cells. GolF treatment of the cancer cells, with the exception of Hep3B, resulted in prompt inhibition of DNA synthesis and arrest of cell progression cycle in G1 phase.

A new N-acetylgalactosamine containing peptide as a targeting vehicle for mammalian hepatocytes via asialoglycoprotein receptor endocytosis.

Galactoside-containing cluster ligands have high affinity for asialoglycoprotein receptors (ASGP-r), which are found in abundance in mammalian parenchymal liver cells. These ligands may be conjugated with a therapeutic drug to improve the efficiency of delivery to diseased liver cells. This report describes a new synthetic route towards clustering glycopeptides containing N-acetyl-D-galactosamine (GalNAc).

Ganoderic acid X, a lanostanoid triterpene, inhibits topoisomerases and induces apoptosis of cancer cells.

Lanostanoid triterpenes isolated from Ganoderma amboinense were found to inhibit the growth of numerous cancer cell lines, and some of them inhibited the activities of topoisomerases I and IIalpha in vitro. Among the bioactive isolates, one of the most potent triterpene was identified to be 3 alpha-hydroxy-15 alpha-acetoxy-lanosta-7,9(11),24-trien-26-oic acid, ganoderic acid X (GAX). Treatment of human hepatoma HuH-7 cells with GAX caused immediate inhibition of DNA synthesis as well as activation of ERK and JNK mitogen-activated protein kinases, and cell apoptosis.

The clinical significance between activation of nuclear factor kappa B transcription factor and overexpression of HER-2/neu oncoprotein in Taiwanese patients with breast cancer.

Background: This study investigated the role of nuclear factor-kappa B (NF-kappaB) activity in human breast cancer with overexpression of HER-2/neu oncoprotein, as well as its role on expression of different histological grades of cancer cells taken from Taiwanese breast cancer patients.

Materials And Methods: Specimens were collected from 82 female breast cancer patients. The HER-2/neu oncoprotein was measured by immunohistochemistry.

Antimutagenicity of supercritical CO2 extracts of Terminalia catappa leaves and cytotoxicity of the extracts to human hepatoma cells.

Natural antimutagens may prevent cancer and are therefore of great interest to oncologists and the public at large. Phytochemicals are potent antimutagen candidates. When the Ames test was applied to examine the antimutagenic potency of supercritical carbon dioxide (SC-CO(2)) extracts of Terminalia catappa leaves at a dose of 0.

Diagnostic value of urine deoxypyridinoline for detecting bone metastases in breast cancer patients.

Deoxypyridinoline (Dpd), a crosslink product of collagen molecules found in bone and excreted in urine during bone degradation, has been described as a marker of bone turnover in metastatic breast cancer. In this study, the urine deoxypyridinoline/creatinine (Dpd/Cre) ratio was determined by enzyme immunoassay in urine samples from 116 women with breast cancer. Bone metastases were confirmed by x-ray or CT scan, with follow-up > 6 mo.

Triterpene-enriched extracts from Ganoderma lucidum inhibit growth of hepatoma cells via suppressing protein kinase C, activating mitogen-activated protein kinases and G2-phase cell cycle arrest.

The medicinal mushroom Ganoderma lucidum (G. lucidum) has been used in the Orient for the prevention and treatment of various diseases including cancer. Except for the immune enhancing properties of its polysaccharide constituent, very little is known about the anticancer activity of another major constituent, triterpenes.

Antioxidative and cytotoxic compounds extracted from the sap of Rhus succedanea.

Two new antioxidative and cytotoxic compounds, 10'(Z),13'(E),15'(E)-heptadecatrienylhydroquinone (1) and 10'(Z),13'(E)-heptadecadienylhydroquinone (2), as well as the known 10'(Z)-heptadecenylhydroquinone (3), were isolated from an EtOH extract of the sap of Rhus succedanea. The structures were elucidated by spectral analyses. These compounds showed antioxidative and cytotoxic activities against five cancer cell lines.