AimTo compare various pro-apoptotic effects of synthetic 4-thiazolidinone derivative (Les-3288), doxorubicin (Dox) and temozolomide (TMZ) in the treatment of human glioma U251 cells to improve treatment outcomes of glioblastoma and avoid anticancer drug resistance.MethodsThe cytotoxic effects of drugs used in human glioma U251 cells were measured by cell viability and proliferation assay (MTT), Trypan blue exclusion test, and Western-blot analysis of the apoptosis-related proteins. In addition, flow cytometry study of reactive oxygen species (ROS) level in glioma cells was carried out. Cytomorphological changes in treated cells were monitored by fluorescent microscopy after cell staining with Hoechst 33342 and ethydium bromide.ResultsHalf-maximal inhibitory concentration (IC50) of Les-3288, Dox, and TMZ was calculated for human glioblastoma U251 cells. The rating of the values of this indicator of cellular vitality was assessed. The results of MTT assay proved the superiority of Les-3288 vs Les-3288>Dox>TMZ, which is in agreement with the results of Trypan blue testing showing Les-3288 ≈ Dox>TMZ. In general, such ranking corresponded to a scale of pro-apoptotic impairments in the morphology of glioma U251 cells and the results of Western-blot analysis of cleaved Caspase 3. Contrary to Dox, Les-3288 and TMZ did not affect significantly ROS levels in the treated cells.ConclusionThe effect of the synthetic 4-thiazolidinone derivative Les-3288 is realized via apoptosis mechanisms and does not involve ROS. In comparison with Dox and TMZ, it is more effective in destroying human glioblastoma U251 cells. Les-3288 compound has a potential as an anticancer drug for glioblastoma. Nevertheless, further preclinical studies of the blood-brain barrier are needed.
Immunoglobulins IgG and sIgA actively hydrolyzing histone H1 have been detected on analyzing proteolytic activity of antibodies isolated by chromatography on Protein A-agarose from blood serum of patients with multiple sclerosis and from colostrum of healthy mothers. These antibodies hydrolyze other histones less actively and virtually failed to cleave lysozyme of chicken egg. By gel filtration at acidic pH and subsequent analysis of protease activity of chromatographic fractions, it was shown that IgG and sIgA molecules were responsible for hydrolysis of histone H1. Anti-histone H1 antibodies of IgG and sIgA classes were purified by affinity chromatography on histone H1-Sepharose from catalytically active antibody preparations. The protease activity of anti-histone H1 IgG antibodies was inhibited by serine proteinase inhibitors, whereas anti-histone H1 sIgA antibodies were insensitive to inhibitors of serine, asparagine, and cysteine proteases.
Autophagy is a degradative process in which cellular organelles and proteins are recycled to restore homeostasis and cellular metabolism. Autophagy can be either a prosurvival or a prodeath process and remains one of the most fundamental processes for cell vitality. Thus autophagy modulation is an important approach for reinforcement anticancer therapeutics. Earlier we have demonstrated that recombinant analog of human milk protein lactaptin (RL2) induced apoptosis of various cultured cancer cells and activated lipidation of microtubule-associated protein 1 light chain 3 (LC3). In this study we investigated whether autophagy inhibitors—chloroquine (CQ), Ku55933 (Ku), and 3-methyladenine (3MA)—or inducer—rapamycin (Rap)—can enhance cytotoxic activity of lactaptin analog in cancer cells and its anticancer activity in the mice model. Western Blot analysis revealed that RL2 induced short-term autophagy in MDA-MB-231 and MCF-7 cells at early stages of incubation and that these data were confirmed by the transmission electron microscopy of autophagosome/autophagolysosome formation. RL2 stimulates reactive oxygen species (ROS) production, autophagosomes accumulation, upregulation of ATG5 with processing of LC3I to LC3II, and downregulation of p62/sequestosome 1 (p62). We have shown that autophagy modulators, CQ, Ku, and Rap, synergistically increased cytotoxicity of RL2, and RL2 with CQ induced autophagic cell death. In addition, CQ, Ku, and Rap in combination with RL2 decreased activity of lysosomal protease Cathepsin D. More importantly, combining RL2 with CQ, we improved antitumor effect in mice. Detected synergistic cytotoxic effects of both types of autophagy regulators, inhibitors, and inducers with RL2 against cancer cells allow us to believe that these combinations can be a basis for the new anticancer approach. Finally, we suppose that CQ and Rap promoting of short-term RL2-induced autophagy interlinks with final autophagic cell death.
We firstly identified 48 kDa molecular form of the unconventional myosin 1c (p48/Myo1C), and isolated it from blood serum of multiple sclerosis patients. The amount of p48/Myo1C in human blood serum correlated with some autoimmune, hemato‐oncological and neurodegenerative diseases and thus may serve as a potential molecular biomarker. The biological functions of this protein in human blood remain unknown. Previously, we used the monodisperse magnetic poly (glycidyl methacrylate)(mag‐PGMA–NH2) microspheres with immobilized 48/Myo1C and western‐blot analysis, which allowed us to identify IgM and IgG immunoglobulins presenting an affinity to this protein. Here, we used mass spectrometry followed by the western blotting in order to identify other blood serum proteins with affinity to 48/Myo1C. The obtained data demonstrate that 48/Myo1C binds to component 3 of the complement and the antithrombin‐III proteins. A combination of magnetic microparticle‐based affinity chromatography with MALDI–TOF mass spectrometry and an in silico analysis provided an opportunity to identify the partners of interaction of 48/Myo1C with other proteins, in particular those participating in complement and coagulation cascades.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.