Differential interactions of the broad spectrum drugs artemisinin, dihydroartemisinin and artesunate with serum albumin.

Artemisinin is a drug, widely used in malaria treatment. As the binding affinity of artemisinin and its derivatives dihydroartemisinin and artesunate to blood serum proteins might influence the effectiveness of the drug, binding of artemisinin and derivatives to serum albumin was studied under near physiological conditions. Binding kinetics indicate a simple, single-step association process for all artemisinin derivatives.

Identification by high-throughput in silico screening of radio-protecting compounds targeting the DNA-binding domain of the tumor suppressor p53.

Therapies targeting p53 mostly concentrate on (re)activation of the p53 protein, to further induce apoptosis in cancer cells. In the present investigations, the focus was on the identification of small molecules that block the DNA-binding domain of p53 and thus inhibit its function. Using high-throughput in silico screening of approximately 300,000 compounds, we identified eight putatively interacting with the DNA-binding domain of p53.

Shikonin directly targets mitochondria and causes mitochondrial dysfunction in cancer cells.

Chemotherapy is a mainstay of cancer treatment. Due to increased drug resistance and the severe side effects of currently used therapeutics, new candidate compounds are required for improvement of therapy success. Shikonin, a natural naphthoquinone, was used in traditional Chinese medicine for the treatment of different inflammatory diseases and recent studies revealed the anticancer activities of shikonin.

Molecular interaction of artemisinin with translationally controlled tumor protein (TCTP) of Plasmodium falciparum.

Malaria causes millions of death cases per year. Since Plasmodium falciparum rapidly develops drug resistance, it is of high importance to investigate potential drug targets which may lead to novel rational therapy approaches. Here we report on the interaction of translationally controlled tumor protein of P.

Inhibition in vivo of the activity of botulinum neurotoxin A by small molecules selected by virtual screening.

To search for small molecular size inhibitors of botulinum neurotoxin A (BoNT/A) endopeptidase activity, we have screened the NCI library containing about 1 million structures against the substrate binding pocket of BoNT/A. Virtual screening (VS) was performed with the software Glide (Grid-based ligand docking energetics) and the findings were confirmed by AutoDock. Ten compounds were found that had favorable energetic and glide criteria and 5 of these compounds were selected for their ability to protect mice in vivo against a lethal dose of BoNT/A.

Cytotoxicity, anti-angiogenic, apoptotic effects and transcript profiling of a naturally occurring naphthyl butenone, guieranone A.

Background: Malignant diseases are responsible of approximately 13% of all deaths each year in the world. Natural products represent a valuable source for the development of novel anticancer drugs. The present study was aimed at evaluating the cytotoxicity of a naphtyl butanone isolated from the leaves of Guiera senegalensis, guieranone A (GA).

Polyhydroxylated steroidal glycosides from Paris polyphylla.

Three new steroidal saponins, parisyunnanosides G-I (1-3), one new C(21) steroidal glycoside, parisyunnanoside J (4), and three known compounds, padelaoside B (5), pinnatasterone (6), and 20-hydroxyecdyson (7), were isolated from the rhizomes of Paris polyphylla Smith var. yunnanensis. Compounds 1 and 3 have unique trisdesmoside structures that include a C-21 β-d-galactopyranose moiety.

Microarray-based mRNA expression profiling of leukemia cells treated with the flavonoid, casticin.

Natural polyphenols play an important role in tumor inhibition. We used a doxorubicin-sensitive acute T-lymphoblastic leukemia cell line (CCRF-CEM) and its multidrug-resistant subline (CEM/ADR5000) to evaluate the activity of 15 plant polyphenols isolated in our laboratory (hypericin and pseudohypericin, verbascoside, ellagic acid, casticin, kaempferol-3-O-(2'',6''-di-E-p-coumaroyl)-glucopyranoside, kaempferol-3-O-(3,4-diacetyl-2,6-di-E-p-coumaroyl) -glucopyranoside, tiliroside, salvianolic acid B, oleuropein, rosmarinic acid, bergenin) or of others from commercial sources (curcumin, epigallocatechin-3-gallate, silymarin). Casticin was the most potent compound (IC50 values of 0.

Specific Cooperation Between Imp-α2 and Imp-β/Ketel in Spindle Assembly During Drosophila Early Nuclear Divisions.

The multifunctional factors Imp-α and Imp-β are involved in nuclear protein import, mitotic spindle dynamics, and nuclear membrane formation. Furthermore, each of the three members of the Imp-α family exerts distinct tasks during development. In Drosophila melanogaster, the imp-α2 gene is critical during oogenesis for ring canal assembly; specific mutations, which allow oogenesis to proceed normally, were found to block early embryonic mitosis.

Utilizing inherent fluorescence of therapeutics to analyze real-time uptake and multi-parametric effector kinetics.

The precise detection of pharmaceutical drug uptake and knowledge of a drug's efficacy at the single-cell level is crucial for understanding a compound's performance. Many pharmaceutical drugs, like the model substances Doxorubicin, Mitoxantrone or Irinotecan, have a distinctive natural fluorescence that can be readily exploited for research purposes. Utilizing this respective natural fluorescence, we propose a method analyzing simultaneously in real-time the efficiency, effects and the associated kinetics of compound-uptake and efflux in mammalian cells by flow cytometry.

Effects of Scrophularia ningpoensis Hemsl. on Inhibition of Proliferation, Apoptosis Induction and NF-κB Signaling of Immortalized and Cancer Cell Lines.

Scrophularia ningpoensis has been used in China for centuries as a herbal tea to treat various diseases. Based on the numerous animal studies on its pharmaceutical effects and the long time clinical experiences, we studied the molecular and cellular mechanism underlying the bioactivity of aqueous extract of Scrophularia and its isolated compounds. Seven isolated compounds, unlike Scrophularia extract, failed to induce cytotoxicity on HaCaT cells, but their combination improved the effect of extract.

P-glycoprotein and its inhibition in tumors by phytochemicals derived from Chinese herbs.

P-glycoprotein belongs to the family of ATP-binding cassette (ABC) transporters. It functions in cellular detoxification, pumping a wide range of xenobiotic compounds, including anticancer drugs out of the cell. In cancerous cells, P-glycoprotein confers resistance to a broad spectrum of anticancer agents, a phenomenon termed multidrug resistance.

Pharmacogenomic determination of genes associated with sensitivity or resistance of tumor cells to curcumin and curcumin derivatives.

Curcuma longa L. has long been used as a medicinal plant in traditional Chinese medicine against abdominal disorders. Its active constituent curcumin has anti-inflammatory, chemopreventive and cytotoxic properties.

Chemical Composition and antiproliferative activity of essential oil from the leaves of a medicinal herb, Levisticum officinale, against UMSCC1 head and neck squamous carcinoma cells.

Background: Oral squamous cell carcinoma (OSCC) is a challenging disease with a high mortality rate. Natural products represent a valuable source for the development of novel anticancer drugs. We investigated the cytotoxic potential of essential oil from the leaves of a medicinal plant, Levisticum officinale (lovage) on head and neck squamous carcinoma cells (HNSCC).

Cytotoxicity of Thymus vulgaris essential oil towards human oral cavity squamous cell carcinoma.

Background: Oral cavity squamous cell carcinoma (OCSCC) accounts for 2% to 3% of all malignancies and has a high mortality rate. The majority of anticancer drugs are of natural origin. However, it is unknown whether the medicinal plant Thymus vulgaris L.

Pharmacogenomic identification of c-Myc/Max-regulated genes associated with cytotoxicity of artesunate towards human colon, ovarian and lung cancer cell lines.

Development of novel therapy strategies is one of the major pressing topics of clinical oncology to overcome drug resistance of tumors. Artesunate (ART) is an anti-malarial drug, which also exerts profound cytotoxic activity towards cancer cells. We applied a gene-hunting approach using microarray-based transcriptome-wide mRNA expression profiling and COMPARE analyses.

Factors determining sensitivity or resistance of tumor cell lines towards artesunate.

Clinical oncology is still challenged by the development of drug resistance of tumors that result in poor prognosis for patients. There is an urgent necessity to understand the molecular mechanisms of resistance and to develop novel therapy strategies. Artesunate (ART) is an anti-malarial drug, which also exerts profound cytotoxic activity towards cancer cells.