Cancer relapse occurs with substantial frequency even after treatment with curative intent. Here we studied drug-tolerant colonies (DTCs), which are subpopulations of cancer cells that survive in the presence of drugs. Proteomic characterization of DTCs identified stemness- and epithelial-dominant subpopulations, but functional screening suggested that DTC formation was regulated at the transcr...

The rapid evolution of toxin resistance in animals has important consequences for the ecology of species and our economy. Pesticide resistance in insects has been a subject of intensive study; however, very little is known about how Drosophila species became resistant to natural toxins with ecological relevance, such as α-amanitin that is produced in deadly poisonous mushrooms. Here we performe...

The aim of the present research was by Electron Paramagnetic Resonance (EPR) spectroscopy using spin trapping technique to study in vitro oxidation of severe mushroom toxin alpha amanitin and second to evaluate its in vivo effect on oxidative status in mice kidney tissue. During in vitro oxidation of alpha amanitin by PbO2 in presence of nitrosobenzene as a spin-trapping agent, a triplet EPR si...

The inhibitory activities of amatoxins on the growth of Chiamydomonas reinhardtii have been determined using a convenient assay based upon incubation in multiwell tissue culture plates followed by turbidimetric estimates of growth on a multiwell plate reader. Values for the inhibitory dosage at which growth is 50% of untreated culture (ID.) of 5.4, 6.6, and 5.6 micromolar were obtained for ci-a...

The transition of phytohemagglutinin-activated human lymphocytes from resting state to proliferation is accompanied by a long-term increase in ouabain-sensitive Rb(K) influx which is closely related to a cyclosporin A-sensitive step of G0/G1/S progression. At least two distinct phases of the up-regulation of cation pump has been revealed: the initial stage (5-20 h) which is cycloheximide-inhibi...

The RNA polymerase activity present in the cytoplasm of BHK cells infected with vaccinia virus is not affected by rifampicin or by alpha-amanitin.

Two RNA polymerases have been purified from the slime mold Physarum polycephalum, one sensitive and one resistant to alpha-amanitin. Both enzymes are more active with denatured DNA than native DNA as a template and prefer Mn(++) rather than Mg(++) as a divalent cation. The alpha-amanitin-sensitive enzyme shows maximum activity at 0.15 M KCl, whereas the resistant enzyme is most active at very l...

27 Amanitins, highly toxic cyclopeptides isolated from various Amanita species, are the 28 most potent poisons accounting for the hazardous effects on intestinal epithelium cells and 29 hepatocytes, and probably the sole cause of fatal human poisoning. 30 The present study was focused on the development, optimization and application of an 31 analytical methodology by ultra performance liquid ch...

BACKGROUND Human epithelial cell adhesion molecule (EpCAM) is overexpressed in many cancers. Anti-EpCAM antibodies have shown promise in preclinical studies, but showed no tumor regression in a recent phase II clinical trial. Therefore, we generated a novel anti-EpCAM antibody-drug conjugate and assessed whether it showed enhanced antitumor effects. METHODS Chemical cross-linking was conducte...

This is an in vivo study detailing the effects of catalase (CAT), superoxide dismutase (SOD) and the level of lipid peroxidation (LPO) products in liver homogenates from mice treated with alpha amanitin or phalloidin. Spectrophotometry was the main method used in this study. Our results showed that both toxins increased SOD activity, confirming an earlier in vitro study. In addition, our presen...