Anticancer effects of NSC­631570 (Ukrain) in head and neck cancer cells: In vitro analysis of growth, invasion, angiogenesis and gene expression.

NSC­631570 (Ukrain) is an aqueous extract of Chelidonium majus, a herbaceous perennial plant, one of two species in the genus Chelidonium, which has been demonstrated to selectively kill tumor cells without affecting non­malignant cells. In the present study, the components of NSC­631570 were examined by combined liquid chromatography/mass spectroscopy (LC­MS) and the effects of NSC­631570 on HNSCC cell lines, as well as primary cells, were analyzed with respect to growth, apoptosis, invasion, angiogenesis and gene expression. LC­MS identified chelerythrine and allocryptopine as the major alkaloids of the extract. Moreover, NSC­631570 suppressed the growth of all tested HNSCC cell lines, including a paclitaxel­resistant and P­glycoprotein (MDR1)­overexpressing cell line. Mucosal keratinocytes were also affected by the extract, while fibroblasts proved to be much more resistant. In contrast to allocryptopine, chelerythrine had toxic effects on HNSCC cell lines at low doses. NSC­631570 significantly induced apoptosis in the FaDu and HLaC78 cell lines. As analyzed by a spheroid­based invasion assay, cell migration was significantly suppressed by NSC­631570 in FaDu cells on gelatine, fibronectin, collagen, laminin and Matrigel®. Migration of the highly invasive cell line HLaC78 was also inhibited, albeit to a lesser extent (not significant on laminin). Microarray analysis revealed the downregulation of genes encoding key regulators, including EGFR, AKT2, JAK1, STAT3 and ß­catenin (CTNNB1), all of which are involved in cell proliferation, migration, angiogenesis, apoptosis as well as the radiation­ and chemo­resistance of HNSCC. The strongest upregulation occurred for cytochrome P450 1A1 (CYP1A1) and 1B1 (CYP1B1), involved in the metabolism of xenobiotics. Upregulation of CYP1A1 was at least partially caused by chelerythrine and allocryptopine, as shown by RT­qPCR in two HNSCC cell lines. In addition, NSC­631570 showed a high anti­angiogenic action on the tube formation ability of human umbilical vein endothelial cells (HUVECs). In conclusion, this study highlights NSC­631570 as a promising therapeutic approach for HNSCC.

A New Bioactive Compound From the Marine Sponge-Derived Streptomyces sp. SBT348 Inhibits Staphylococcal Growth and Biofilm Formation.

Staphylococcus epidermidis, the common inhabitant of human skin and mucosal surfaces has emerged as an important pathogen in patients carrying surgical implants and medical devices. Entering the body via surgical sites and colonizing the medical devices through formation of multi-layered biofilms leads to refractory and persistent device-related infections (DRIs). Staphylococci organized in biofilms are more tolerant to antibiotics and immune responses, and thus are difficult-to-treat. The consequent morbidity and mortality, and economic losses in health care systems has strongly necessitated the need for development of new anti-bacterial and anti-biofilm-based therapeutics. In this study, we describe the biological activity of a marine sponge-derived Streptomyces sp. SBT348 extract in restraining staphylococcal growth and biofilm formation on polystyrene, glass, medically relevant titan metal, and silicone surfaces. A bioassay-guided fractionation was performed to isolate the active compound (SKC3) from the crude SBT348 extract. Our results demonstrated that SKC3 effectively inhibits the growth (MIC: 31.25 µg/ml) and biofilm formation (sub-MIC range: 1.95-<31.25 µg/ml) of S. epidermidis RP62A in vitro. Chemical characterization of SKC3 by heat and enzyme treatments, and mass spectrometry (HRMS) revealed its heat-stable and non-proteinaceous nature, and high molecular weight (1258.3 Da). Cytotoxicity profiling of SKC3 in vitro on mouse fibroblast (NIH/3T3) and macrophage (J774.1) cell lines, and in vivo on the greater wax moth larvae Galleria mellonella revealed its non-toxic nature at the effective dose. Transcriptome analysis of SKC3 treated S. epidermidis RP62A has further unmasked its negative effect on central metabolism such as carbon flux as well as, amino acid, lipid, and energy metabolism. Taken together, these findings suggest a potential of SKC3 as a putative drug to prevent staphylococcal DRIs.

Fluorine walk: The impact of fluorine in quinolone amides on their activity against African sleeping sickness.

Human African Trypanosomiasis, also known as African sleeping sickness, is caused by the parasitic protozoa of the genus Trypanosoma. If there is no pharmacological intervention, the parasites can cross the blood-brain barrier (BBB), inevitably leading to death of the patients. Previous investigation identified the quinolone amide GHQ168 as a promising lead compound having a nanomolar activity against T. b. brucei. Here, the role of a fluorine substitution at different positions was investigated in regard to toxicity, pharmacokinetics, and antitrypanosomal activity. This 'fluorine walk' led to new compounds with improved metabolic stability and consistent activity against T. b. brucei. The ability of the new quinolone amides to cross the BBB was confirmed using an 18F-labelled quinolone amide derivative by means of ex vivo autoradiography of a murine brain.

Improving anti-trypanosomal activity of alkamides isolated from Achillea fragrantissima.

In previous studies the aerial parts of Achillea fragrantissima were found to have substantial antileishmanial and antitrypanosomal activity. A bioassay-guided fractionation of a dichloromethane extract yielded the isolation of the essential anti-trypanosomal compounds of the plant. Seven sesquiterpene lactones (including Achillolide-A), two flavonoids, chrysosplenol-D and chrysosplenetine, and four alkamides (including pellitorine) were identified. This is the first report for the isolation of the sesquiterpene lactones 3 and 4, chrysosplenetine and the group of alkamides from this plant. Bioevaluation against Trypanosoma brucei brucei TC221 (T.b brucei) using the Alamar-Blue assay revealed the novel alkamide 13 to have an IC50 value of 40.37µM. A compound library, derived from the alkamide pellitorine (10), was synthesized and bioevaluated in order to find even more active substances. The most active compounds 26 and 27 showed activities in submicromolar concentrations and selectivity indices of 20.1 and 45.6, respectively, towards macrophage cell line J774.1. Toxicity of 26 and 27 was assessed using the greater wax moth Galleria mellonella larvae as an in vivo model. No significant toxicity was observed for the concentration range of 1.25-20mM.