Defects in cell death signaling pathways are one of the hallmarks of cancer and can lead to resistance to conventional therapy. Natural products are promising compounds that can overcome this resistance. In the present study we studied the effect of six quaternary benzophenanthridine alkaloids (QBAs), sanguinarine, chelerythrine, sanguirubine, chelirubine, sanguilutine, and chelilutine, on Jurkat leukemia cells, WT, and cell death deficient lines derived from them, CASP3/7/6-/- and FADD-/-, and on solid tumor, human malignant melanoma, A375 cells. We demonstrated the ability of QBAs to overcome the resistance of these deficient cells and identified a novel mechanism for their action. Sanguinarine and sanguirubine completely and chelerythrine, sanguilutine, and chelilutine partially overcame the resistance of CASP3/7/6-/- and FADD-/- cells. By detection of cPARP, a marker of apoptosis, and pMLKL, a marker of necroptosis, we proved the ability of QBAs to induce both these cell deaths (bimodal cell death) with apoptosis preceding necroptosis. We identified the new mechanism of the cell death induction by QBAs, the downregulation of the apoptosis inhibitors cIAP1 and cIAP2, i.e., an effect similar to that of Smac mimetics.
- MeSH
- alkaloidy * farmakologie metabolismus MeSH
- apoptóza * MeSH
- benzofenantridiny farmakologie MeSH
- kaspasa 3 metabolismus MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- signální transdukce MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
The phenolic compounds of methanolic extracts of Salvia pomifera and Salvia fruticosa were identified by liquid chromatography tandem mass spectrometry. Carnosic acid and its metabolite carnosol were the most abundant terpene phenolic compounds of S. fruticosa, while they were completely absent in S. pomifera. The main terpene phenolic constituent of S. pomifera was 12-O-methylcarnosic acid and its mass/mass fragmentation pathway was explained. The detailed mechanism of carnosic acid oxidation to carnosol was suggested. The effects of Salvia extracts and/or carnosic acid, the main diterpene phenolic component of S. fruticosa, on the proliferation and cell cycle of two melanoma cell lines (A375, Mel JuSo) and human fibroblast cell line (HFF) were investigated by MTT assay, PI-exclusion assay and flow cytometry cell cycle analysis. Extract of S. fruticosa more efficiently than S. pomifera extract reduced the proliferation of the human melanoma cells. Carnosic acid showed the most significant effect. The first evidence that carnosic acid affects microtubule dynamics and arrests the cell cycle in the G2/M phase was provided. Collectively, our results demonstrate that these two Salvia species are plants of medicinal interest with perspective for further investigation. Carnosic acid could be the compound responsible for the biological activities of S. fruticosa extracts.
- MeSH
- antitumorózní látky chemie izolace a purifikace farmakologie MeSH
- buněčné linie MeSH
- diterpeny abietanové chemie izolace a purifikace farmakologie MeSH
- epitelové buňky účinky léků patologie MeSH
- fenoly chemie izolace a purifikace farmakologie MeSH
- fibroblasty cytologie účinky léků MeSH
- inhibiční koncentrace 50 MeSH
- kontrolní body fáze G2 buněčného cyklu účinky léků MeSH
- lidé MeSH
- methanol chemie MeSH
- nádorové buněčné linie MeSH
- nadzemní části rostlin chemie MeSH
- oxidace-redukce MeSH
- proliferace buněk účinky léků MeSH
- rostlinné extrakty chemie MeSH
- rozpouštědla chemie MeSH
- šalvěj chemie MeSH
- viabilita buněk účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Tumor suppressor p53 is mutated in about 50% of cancers. Most malignant melanomas carry wild-type p53, but p53 activity is often inhibited due to overexpression of its negative regulators Mdm2 or MdmX. We performed high throughput screening of 2448 compounds on A375 cells carrying p53 activity luciferase reporter construct to reveal compounds that promote p53 activity in melanoma. Albendazole and fenbendazole, two approved and commonly used benzimidazole anthelmintics, stimulated p53 activity and were selected for further studies. The protein levels of p53 and p21 increased upon the treatment with albendazole and fenbendazole, indicating activation of the p53-p21 pathway, while the levels of Mdm2 and MdmX decreased in melanoma and breast cancer cells overexpressing these proteins. We also observed a reduction of cell viability and changes of cellular morphology corresponding to mitotic catastrophe, i.e., G2/M cell cycle arrest of large multinucleated cells with disrupted microtubules. In summary, we established a new tool for testing the impact of small molecule compounds on the activity of p53 and used it to identify the action of benzimidazoles in melanoma cells. The drugs promoted the stability and transcriptional activity of wild-type p53 via downregulation of its negative regulators Mdm2 and MdmX in cells overexpressing these proteins. The results indicate the potential for repurposing the benzimidazole anthelmintics for the treatment of cancers overexpressing p53 negative regulators.
- MeSH
- albendazol farmakologie MeSH
- benzimidazoly farmakologie MeSH
- down regulace MeSH
- fenbendazol farmakologie MeSH
- jaderné proteiny metabolismus MeSH
- léky antitumorózní - screeningové testy MeSH
- lidé MeSH
- melanom farmakoterapie metabolismus MeSH
- MFC-7 buňky MeSH
- nádorové buněčné linie MeSH
- nádorový supresorový protein p53 metabolismus MeSH
- přehodnocení terapeutických indikací léčivého přípravku MeSH
- proliferace buněk účinky léků MeSH
- proteiny buněčného cyklu MeSH
- protoonkogenní proteiny c-mdm2 metabolismus MeSH
- protoonkogenní proteiny metabolismus MeSH
- regulace genové exprese u nádorů účinky léků MeSH
- rychlé screeningové testy MeSH
- viabilita buněk účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
This study examined the sequences of the two rRNA (rrn) operons of pathogenic non-cultivable treponemes, comprising 11 strains of T. pallidum ssp. pallidum (TPA), five strains of T. pallidum ssp. pertenue (TPE), two strains of T. pallidum ssp. endemicum (TEN), a simian Fribourg-Blanc strain and a rabbit T. paraluiscuniculi (TPc) strain. PCR was used to determine the type of 16S-23S ribosomal intergenic spacers in the rrn operons from 30 clinical samples belonging to five different genotypes. When compared with the TPA strains, TPc Cuniculi A strain had a 17 bp deletion, and the TPE, TEN and Fribourg-Blanc isolates had a deletion of 33 bp. Other than these deletions, only 17 heterogeneous sites were found within the entire region (excluding the 16S-23S intergenic spacer region encoding tRNA-Ile or tRNA-Ala). The pattern of nucleotide changes in the rrn operons corresponded to the classification of treponemal strains, whilst two different rrn spacer patterns (Ile/Ala and Ala/Ile) appeared to be distributed randomly across species/subspecies classification, time and geographical source of the treponemal strains. It is suggested that the random distribution of tRNA genes is caused by reciprocal translocation between repetitive sequences mediated by a recBCD-like system.
- MeSH
- DNA bakterií chemie genetika MeSH
- fylogeneze MeSH
- genetická variace MeSH
- genom bakteriální MeSH
- genotyp MeSH
- mezerníky ribozomální DNA genetika MeSH
- molekulární sekvence - údaje MeSH
- RNA ribozomální 16S genetika MeSH
- RNA ribozomální 23S genetika MeSH
- rRNA Operon * MeSH
- sekvence nukleotidů MeSH
- sekvenční analýza DNA MeSH
- sekvenční delece MeSH
- Treponema pallidum klasifikace genetika MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The unique long-neck yeast Fellomyces fuzhouensis has F-actin cables and cortical patches. Here, we describe a new F-actin structure present in fungi, a perinuclear F-actin collar ring around the cell nucleus. This F-actin structure can be visualized by fluorescent microscopic imaging of rhodamine-phalloidin-stained F-actin in cells treated with the mitotic drug isopropyl N-(3-chlorophenyl) carbamate or the microtubule inhibitor thiabendazol or when cells were grown in cut dried radish medium or yeast extract pepton dextrose (YEPD) medium. In contrast, these structures were absent in cells treated with Latrunculin A. The hypothetical functions of the F-actin ring are discussed.
- MeSH
- aktiny metabolismus MeSH
- Basidiomycota účinky léků růst a vývoj metabolismus ultrastruktura MeSH
- bicyklické sloučeniny heterocyklické farmakologie MeSH
- buněčné jádro metabolismus MeSH
- fluorescenční mikroskopie MeSH
- mikrofilamenta metabolismus ultrastruktura MeSH
- thiazolidiny farmakologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
