The natural product colchicine (Col) is a medication used to treat severe inflammatory conditions. Although its mechanism of action at the level of the cytoskeleton is known, its subcellular distribution has not yet been properly studied. In this work, we present the first rational approach to assess the intracellular localization and biological activity of this alkaloid. We conjugated Col to green-emitting BODIPY dyes (CBs) with alternative linkers of different lengths (CB1-CB12) via different types of linkages. Connections of Col with BODIPY generally reduced its cytotoxicity to different levels depending on the type of linker. From the analysis of CB effects on cytotoxicity, cell cycle, and tubulin polymerization, we selected the most potent substances for fluorescence microscopy. Treatment of cells with 10 μM conjugates for 15 h showed different effects on microtubule organization. Live-cell imaging revealed that CBs rapidly associated with cellular membranes. Double label experiments unveiled that the CB4, which was the most effective in inhibiting tubulin polymerization, binds to the endoplasmic reticulum (ER) and mitochondria. In silico modeling and SPR analyses confirmed the high potency of CB4 to bind to the colchicine site on tubulin.
- Keywords
- BODIPY, cell-cycle, colchicine, cytotoxicity, flow-cytometry, fluorescence microscopy, in silico modeling, intracellular membranes, tubulin polymerization,
- Publication type
- Journal Article MeSH
A series of quinolino-fused 7-deazapurine (pyrimido[5',4':4,5]pyrrolo[3,2-f]quinoline) ribonucleosides were designed and synthesized. The synthesis of the key 11-chloro-pyrimido[5',4':4,5]pyrrolo[3,2-f]quinoline was based on the Negishi cross-coupling of iodoquinoline with zincated 4,6-dichloropyrimidine followed by azidation and thermal or photochemical cyclization. Vorbrüggen glycosylation of the tetracyclic heterocycle followed by cross-coupling or substitution reactions at position 11 gave the desired set of final nucleosides that showed moderate to weak cytostatic activity and fluorescent properties. The corresponding fused adenosine derivative was converted to the triphosphate and successfully incorporated to RNA using in vitro transcription with T7 RNA polymerase.
- Publication type
- Journal Article MeSH
A new approach for synthesizing polycyclic heterofused 7-deazapurine heterocycles and the corresponding nucleosides was developed based on C-H functionalization of diverse (hetero)aromatics with dibenzothiophene-S-oxide followed by the Negishi cross-cooupling with bis(4,6-dichloropyrimidin-5-yl)zinc. This cross-coupling afforded a series of (het)aryl-pyrimidines that were converted to fused deazapurine heterocycles through azidation and thermal cyclization. The fused heterocycles were glycosylated to the corresponding 2'-deoxy- and ribonucleosides, and a series of derivatives were prepared by nucleophilic substitutions at position 4. Four series of new polycyclic thieno-fused 7-deazapurine nucleosides were synthesized using this strategy. Most of the deoxyribonucleosides showed good cytotoxic activity, especially for the CCRF-CEM cell line. Phenyl- and thienyl-substituted thieno-fused 7-deazapurine nucleosides were fluorescent, and the former one was converted to 2'-deoxyribonucleoside triphosphate for enzymatic synthesis of labeled oligonucleotides.
- MeSH
- Deoxyribonucleosides MeSH
- Cell Line, Tumor MeSH
- Nucleosides * MeSH
- Oligonucleotides MeSH
- Oxides MeSH
- Purine Nucleosides MeSH
- Pyrimidines MeSH
- Ribonucleosides * MeSH
- Zinc MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- 7-deazapurine MeSH Browser
- Deoxyribonucleosides MeSH
- Nucleosides * MeSH
- Oligonucleotides MeSH
- Oxides MeSH
- Purine Nucleosides MeSH
- Pyrimidines MeSH
- Ribonucleosides * MeSH
- Zinc MeSH
The coexistence of leishmaniasis, Chagas disease, and neoplasia in endemic areas has been extensively documented. The use of common drugs in the treatment of these pathologies invites us to search for new molecules with these characteristics. In this research, we report 16 synthetic chalcone derivatives that were investigated for leishmanicidal and trypanocidal activities as well as for antiproliferative potential on eight human cancers and two nontumor cell lines. The final compounds 8−23 were obtained using the classical base-catalyzed Claisen−Schmidt condensation. The most potent compounds as parasiticidal were found to be 22 and 23, while compounds 18 and 22 showed the best antiproliferative activity and therapeutic index against CCRF-CEM, K562, A549, and U2OS cancer cell lines and non-toxic VERO, BMDM, MRC-5, and BJ cells. In the case of K562 and the corresponding drug-resistant K562-TAX cell lines, the antiproliferative activity has shown a more significant difference for compound 19 having 10.3 times higher activity against the K562-TAX than K562 cell line. Flow cytometry analysis using K562 and A549 cell lines cultured with compounds 18 and 22 confirmed the induction of apoptosis in treated cells after 24 h. Based on the structural analysis, these chalcones represent new compounds potentially useful for Leishmania, Trypanosoma cruzi, and some cancer treatments.
- Keywords
- Leishmaniasis, Trypanosoma cruzi, apoptosis, cancer, chalcone,
- MeSH
- Chagas Disease * drug therapy MeSH
- Chalcone * pharmacology MeSH
- Leishmania * MeSH
- Leishmaniasis * drug therapy MeSH
- Humans MeSH
- Naphthalenes therapeutic use MeSH
- Trypanocidal Agents * chemistry MeSH
- Trypanosoma cruzi * MeSH
- Structure-Activity Relationship MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Chalcone * MeSH
- Naphthalenes MeSH
- Trypanocidal Agents * MeSH
Specific A3 adenosine receptor (A3AR) agonist, 2‑chloro‑N6‑(3‑iodobenzyl)‑5'‑N‑methylcarboxamidoadenosine (2‑Cl‑IB‑MECA), demonstrates anti‑proliferative effects on various types of tumor. In the present study, the cytotoxicity of 2‑Cl‑IB‑MECA was analyzed in a panel of tumor and non‑tumor cell lines and its anticancer mechanisms in JoPaca‑1 pancreatic and Hep‑3B hepatocellular carcinoma cell lines were also investigated. Initially, decreased tumor cell proliferation, cell accumulation in the G1 phase and inhibition of DNA and RNA synthesis was found. Furthermore, western blot analysis showed decreased protein expression level of β‑catenin, patched1 (Ptch1) and glioma‑associated oncogene homolog zinc finger protein 1 (Gli1), which are components of the Wnt/β‑catenin and Sonic hedgehog/Ptch/Gli transduction pathways. In concordance with these findings, the protein expression levels of cyclin D1 and c‑Myc were reduced. Using a luciferase assay, it was revealed for the first time a decrease in β‑catenin transcriptional activity, as an early event following 2‑Cl‑IB‑MECA treatment. In addition, the protein expression levels of multidrug resistance‑associated protein 1 and P‑glycoprotein (P‑gp) were reduced and the P‑gp xenobiotic efflux function was also reduced. Next, the enhancing effects of 2‑Cl‑IB‑MECA on the cytotoxicity of conventional chemotherapy was investigated. It was found that 2‑Cl‑IB‑MECA enhanced carboplatin and doxorubicin cytotoxic effects in the JoPaca‑1 and Hep‑3B cell lines, and a greater synergy was found in the highly tumorigenic JoPaca‑1 cell line. This provides a novel in vitro rationale for the utilization of 2‑Cl‑IB‑MECA in combination with chemotherapeutic agents, not only for hepatocellular carcinoma, but also for pancreatic cancer. Other currently used conventional chemotherapeutics, fluorouracil and gemcitabine, showed synergy only when combined with high doses of 2‑Cl‑IB‑MECA. Notably, experiments with A3AR‑specific antagonist, N‑[9‑Chloro‑2‑(2‑furanyl)(1,2,4)‑triazolo(1,5‑c)quinazolin‑5‑yl]benzene acetamide, revealed that 2‑Cl‑IB‑MECA had antitumor effects via both A3AR‑dependent and ‑independent pathways. In conclusion, the present study identified novel antitumor mechanisms of 2‑Cl‑IB‑MECA in pancreatic and hepatocellular carcinoma in vitro that further underscores the importance of A3AR agonists in cancer therapy.
- Keywords
- 2‑Cl‑IB‑MECA, adenosine A3 receptor, chemosensitivity, hepatocellular carcinoma, multidrug resistance, pancreatic carcinoma,
- MeSH
- Adenosine analogs & derivatives MeSH
- Cell Line MeSH
- Drug Resistance MeSH
- Humans MeSH
- Cell Line, Tumor MeSH
- Liver Neoplasms * drug therapy MeSH
- Pancreatic Neoplasms * genetics MeSH
- Cell Proliferation MeSH
- Zinc Finger Protein GLI1 genetics metabolism MeSH
- Hedgehog Proteins MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- 2-chloro-N(6)-(3-iodobenzyl)adenosine-5'-N-methyluronamide MeSH Browser
- Adenosine MeSH
- Zinc Finger Protein GLI1 MeSH
- Hedgehog Proteins MeSH
Two isomeric sets of 4-substituted pyridopyrrolopyrimidine nucleobases were prepared through nucleophilic substitutions or cross-coupling reactions of 4-chloropyridopyrrolopyrimidines. The corresponding 4-amino-pyridopyrrolopyrimidines were glycosylated with 5-O-tritylribose using the modified Mitsunobu protocol. Several examples of the title heterocycles showed blue or green fluorescence. Testing of the pyridopyrrolopyrimidine nucleobases for the cytotoxic effect revealed micromolar activity of 4-benzofuryl derivatives in both series, preferentially in multidrug-resistant cancers.
- Publication type
- Journal Article MeSH
Inhibition of the biosynthesis of complex N-glycans in the Golgi apparatus influences progress of tumor growth and metastasis. Golgi α-mannosidase II (GMII) has become a therapeutic target for drugs with anticancer activities. One critical task for successful application of GMII drugs in medical treatments is to decrease their unwanted co-inhibition of lysosomal α-mannosidase (LMan), a weakness of all known potent GMII inhibitors. A series of novel N-substituted polyhydroxypyrrolidines was synthesized and tested with modeled GH38 α-mannosidases from Drosophila melanogaster (GMIIb and LManII). The most potent structures inhibited GMIIb (Ki =50-76 μm, as determined by enzyme assays) with a significant selectivity index of IC50 (LManII)/IC50 (GMIIb) >100. These compounds also showed inhibitory activities in in vitro assays with cancer cell lines (leukemia, IC50 =92-200 μm) and low cytotoxic activities in normal fibroblast cell lines (IC50 >200 μm). In addition, they did not show any significant inhibitory activity toward GH47 Aspergillus saitoiα1,2-mannosidase. An appropriate stereo configuration of hydroxymethyl and benzyl functional groups on the pyrrolidine ring of the inhibitor may lead to an inhibitor with the required selectivity for the active site of a target α-mannosidase.
- Keywords
- Golgi α-mannosidase II, cytotoxicity, molecular modeling, pyrrolidines, swainsonine,
- MeSH
- Aspergillus enzymology MeSH
- Cell Line MeSH
- Drosophila melanogaster enzymology MeSH
- Nitrogen chemistry MeSH
- Fungal Proteins antagonists & inhibitors metabolism MeSH
- Golgi Apparatus enzymology MeSH
- Inhibitory Concentration 50 MeSH
- Catalytic Domain MeSH
- Humans MeSH
- Mannosidases antagonists & inhibitors metabolism MeSH
- Pyrrolidines chemistry metabolism pharmacology MeSH
- Molecular Docking Simulation MeSH
- Binding Sites MeSH
- Cell Survival drug effects MeSH
- Structure-Activity Relationship MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Nitrogen MeSH
- Fungal Proteins MeSH
- Mannosidases MeSH
- mannosyl-oligosaccharide 1,3 - 1,6-alpha-mannosidase MeSH Browser
- Pyrrolidines MeSH
In this work, we describe synthesis of conjugates of betulinic acid with substituted triazoles prepared via Huisgen 1,3-cycloaddition. All compounds contain free 28-COOH group. Allylic bromination of protected betulinic acid by NBS gave corresponding 30-bromoderivatives, their substitution with sodium azides produced 30-azidoderivatives and these azides were subjected to CuI catalysed Huisgen 1,3-cycloaddition to give the final conjugates. Reactions had moderate to high yields. All new compounds were tested for their in vitro cytotoxic activities on eight cancer and two non-cancer cell lines. The most active compounds were conjugates of 3β-O-acetylbetulinic acid and among them, conjugate with triazole substituted by benzaldehyde 9b was the best with IC50 of 3.3 μM and therapeutic index of 9.1. Five compounds in this study had IC50 below 10 μM and inhibited DNA and RNA synthesis and caused block in G0/G1 cell cycle phase which is highly similar to actinomycin D. It is unusual that here prepared 3β-O-acetates were more active than compounds with the free 3-OH group and this suggests that this set may have common mechanism of action that is different from the mechanism of action of previously known 3β-O-acetoxybetulinic acid derivatives. Benzaldehyde type conjugate 9b is the best candidate for further drug development.
- MeSH
- Benzaldehydes chemistry MeSH
- Cell Cycle drug effects MeSH
- Cycloaddition Reaction MeSH
- Betulinic Acid MeSH
- Humans MeSH
- Cell Line, Tumor MeSH
- Pentacyclic Triterpenes MeSH
- Antineoplastic Agents chemistry pharmacology MeSH
- Triazoles chemistry MeSH
- Triterpenes chemistry MeSH
- Cell Survival drug effects MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- benzaldehyde MeSH Browser
- Benzaldehydes MeSH
- Betulinic Acid MeSH
- Pentacyclic Triterpenes MeSH
- Antineoplastic Agents MeSH
- Triazoles MeSH
- Triterpenes MeSH
