Synthetic approaches to difluoroindolecarboxylic acid ethyl esters

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Mitotic cell death induction by targeting the mitotic spindle with tubulin-inhibitory indole derivative molecules

Tubulin-targeting molecules are widely used cancer therapeutic agents. They inhibit microtubule-based structures, including the mitotic spindle, ultimately preventing cell division. The final fates of microtubule-inhibited cells are however often heterogeneous and difficult to predict. While recent work has provided insight into the cell response to inhibitors of microtubule dynamics (taxanes), the cell response to tubulin polymerization inhibitors remains less well characterized. Arylthioindoles (ATIs) are recently developed tubulin inhibitors. We previously identified ATI members that effectively inhibit tubulin polymerization in vitro and cancer cell growth in bulk cell viability assays. Here we characterise in depth the response of cancer cell lines to five selected ATIs. We find that all ATIs arrest mitotic progression, yet subsequently yield distinct cell fate profiles in time-lapse recording assays, indicating that molecules endowed with similar tubulin polymerization inhibitory activity in vitro can in fact display differential efficacy in living cells. Individual ATIs induce cytological phenotypes of increasing severity in terms of damage to the mitotic apparatus. That differentially triggers MCL-1 down-regulation and caspase-3 activation, and underlies the terminal fate of treated cells. Collectively, these results contribute to define the cell response to tubulin inhibitors and pinpoint potentially valuable molecules that can increase the molecular diversity of tubulin-targeting agents

Violacein, an indole-derived purple-colored natural pigment produced by Janthinobacterium lividum, inhibits the growth of head and neck carcinoma cell lines both in vitro and in vivo

Violacein (VIO; 3-[1,2-dihydro-5-(5-hydroxy-1H-indol-3-yl)-2-oxo-3H-pyrrol-3-ylidene]-1,3-dihydro-2H-indol-2-one), an indole-derived purple-colored pigment, produced by a limited number of Gram-negative bacteria species, including Chromobacterium violaceum and Janthinobacterium lividum, has been demonstrated to have anti-cancer activity, as it interferes with survival transduction signaling pathways in different cancer models. Head and neck carcinoma (HNC) represents the sixth most common and one of the most fatal cancers worldwide. We determined whether VIO was able to inhibit head and neck cancer cell growth both in vitro and in vivo. We provide evidence that VIO treatment of human and mouse head and neck cancer cell lines inhibits cell growth and induces autophagy and apoptosis. In fact, VIO treatment increased PARP-1 cleavage, the Bax/Bcl-2 ratio, the inhibition of ERK1 and ERK2 phosphorylation, and the expression of light chain 3-II (LC3-II). Moreover, VIO was able to induce p53 degradation, cytoplasmic nuclear factor kappa B (NF-κB) accumulation, and reactive oxygen species (ROS) production. VIO induced a significant increase in ROS production. VIO administration was safe in BALB/c mice and reduced the growth of transplanted salivary gland cancer cells (SALTO) in vivo and prolonged median survival. Taken together, our results indicate that the treatment of head and neck cancer cells with VIO can be useful in inhibiting in vivo and in vitro cancer cell growth. VIO may represent a suitable tool for the local treatment of HNC in combination with standard therapies

RS4651 suppresses lung fibroblast activation via the TGF-β1/SMAD signalling pathway.

ABSTRACT Background Idiopathic pulmonary fibrosis (IPF) is a progressive disease resulting in respiratory failure with no efficient treatment options. We investigated the protective effect of RS4651 on pulmonary fibrosis in mice and the mechanism. Methods Intratracheal injection of bleomycin (BLM) was used to induce pulmonary fibrosis in mice. RS4561 was administered intraperitoneally at different doses. Histopathological changes were observed. The level of alpha-smooth muscle actin (α-SMA) were also tested. In vitro, the proliferation and migratory effects of RS4651 treatment on MRC-5 cells pre-treated with transforming growth factor (TGF-β1) were examined. RNA-sequencing was used to detect differentially expressed target genes. Then, the expression of α-SMA, pSMAD2 and SMAD7 were analysed during RS4651 treatment of MRC-5 cells with or without silencing by SMAD7 siRNA. Results Histopathological staining results showed decreased collagen deposition in RS4651 administered mice. Additionally, a lower level of α-SMA was also observed compared to the BLM group. The results of in vitro studies confirmed that RS4651 can inhibit the proliferation and migration, as well as α-SMA and pSMAD2 expression in MRC-5 cells treated with TGF-β1. RNA-sequencing data identified the target gene SMAD7. We found that RS4651 could upregulate SMAD7 expression and inhibit the proliferation and migration of MRC-5 cells via SMAD7, and RS4651 inhibition of α-SMA and pSMAD2 expression was blocked in SMAD7-siRNA MRC-5 cells. In vivo studies further confirmed that RS4651 could upregulate SMAD7 expression in BLM-induced lung fibrosis in mice. Conclusions Our data suggest that RS4651 alleviates BLM-induced pulmonary fibrosis in mice by inhibiting the TGF-β1/SMAD signalling pathway

Indolyl aryl sulphones as HIV-1 non-nucleoside reverse transcriptase inhibitors: synthesis, biological evaluation and binding mode studies of new derivatives at indole-2-carboxamide.

New non-nucleoside reverse transcriptase inhibitors (NNRTIs) that are active against the commonly occurring mutations of HIV are urgently needed for the treatment of AIDS. We synthesized new NNRTIs of the indolyl aryl sulphone (IAS) family, which are endowed with high antiviral potency against HIV-1 wt (wild-type), and the Y181C and K103N-Y181C drug resistant mutant strains. Several new compounds were highly active in lymphocytes infected with primary isolates carrying the K103N-V108I-M184V and L100I-V108I mutations. The design of new IASs was based on three-dimensional quantitative structure-activity relationship (3D QSAR) studies and docking simulations. A cross-docking study was also undertaken to gain some insights in to the binding mode of the newly synthesized IASs in the wt and mutated isoforms of reverse transcriptase

PYRROLO[1,2-b][1,2,5]BENZOTHIADIAZEPINES (PBTDs) induce apoptosis in K562 cells

BACKGROUND: The objective of this study was to gain insight into the molecular mechanism of induced cell death (apoptosis) by PYRROLO [1,2-b][1,2,5]BENZOTHIADIAZEPINES (PBTDs) series compounds, using human (K562) cells as a model. METHODS: We focused our attention on some members of the PBTDs family to test their potential apoptotic activity in K562 cells. Important apoptotic activity was demonstrated, as evidenced by the concentration and percentage of cell death quantified by measuring PI-uptake by flow cytometry, and DNA fragmentation analyzed by agarose gel electrophoresis, generating a characteristic ladder pattern of discontinuous DNA fragments. The expression of Bcl-2 family was tested using western blotting and transfection method. RESULTS: PBTDs-mediated suppression of K562 cell proliferation was induced by apoptosis characterized by the appearance of DNA fragmentation and was associated with the poly(ADP-ribose)polymerase (PARP) cleavage. PBTD-1 and -3 treatment resulted in caspase-3 activation through down-regulation of Bcl-2 and up-regulation of Bax. Furthermore, we used K562/vector and K562/bcl-2 cells, which were generated by transfection of the cDNA of the Bcl-2 gene. As compared with K562/vector, K562/Bcl-2 cells exhibited a 4-fold greater expression of Bcl-2. Treatment with 10 muM PBTD-1 and -3 for 24 h produced morphological features of apoptosis and DNA fragmentation in K562/vector cells, respectively. In contrast, PBTD-1 and -3-induced caspase-3 activation and apoptosis were inhibited in K562/Bcl-2. Furthermore, Bcl-2 overexpressing cells exhibited less cytocrome c release during PBTDs-induced apoptosis. CONCLUSION: These results indicate that PBTDs effectively induce apoptosis of K562 leukemia cells through the activation of caspase cascades. In addition, these findings indicate that Bcl-2 inhibits PBTD-1 and -3 induced-apoptosis via a mechanism that interferes with cytocrome c release, and the activity of caspase-3, which is involved in the execution of apoptosis

Supplementary data for article: Filipović, N. R.; Bjelogrlić, S. K.; Pelliccia, S.; Jovanović, V. B.; Kojić, M.; Senćanski, M.; La Regina, G.; Silvestri, R.; Muller, C. D.; Todorović, T. R. Selenotriapine - An Isostere of the Most Studied Thiosemicarbazone with Pronounced pro-Apoptotic Activity, Low Toxicity and Ability to Challenge Phenotype Reprogramming of 3-D Mammary Adenocarcinoma Tumors, 2017. https://doi.org/10.1016/j.arabjc.2017.11.017

Supplementary material for: [https://doi.org/10.1016/j.arabjc.2017.11.017]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/320

Novel N-(Heterocyclylphenyl)benzensulfonamide Sharing an Unreported Binding Site with T-Cell Factor 4 at the β-Catenin Armadillo Repeats Domain as an Anticancer Agent

Despite intensive efforts, no inhibitors of the Wnt/beta-catenin signaling pathway have been approved so far for the clinical treatment of cancer. We synthesized novel N-(heterocyclylphenyl)benzenesulfonamides as beta-catenin inhibitors. Compounds 5-10 showed strong inhibition of the luciferase activity. Compounds 5 and 6 inhibited the MDA-MB-231, HCC1806, and HCC1937 TNBC cells. Compound 9 induced in vitro cell death in SW480 and HCT116 cells and in vivo tumorigenicity of a human colorectal cancer line HCT116. In a co-immunoprecipitation study in HCT116 cells transfected with Myc-tagged T-cell factor 4 (Tcf-4), compound 9 abrogated the association between beta-catenin and Tcf-4. The crystallographic analysis of the beta-catenin Armadillo repeats domain revealed that compound 9 and Tcf-4 share a common binding site within the hotspot binding region close to Lys508. To our knowledge, compound 9 is the first small molecule ligand of this region to be reported. These results highlight the potential of this novel class of beta-catenin inhibitors as anticancer agents

Chiral indolylarylsulfone non-nucleoside reverse transcriptase inhibitors as new potent and broad spectrum anti-HIV-1 agents

We designed and synthesized a series of chiral indolyarylsulfones (IASs) as new HIV-1 NNRTIs. The new IASs 8–37 showed potent inhibition of the HIV-1 WT NL4-3 strain and of the mutant K103N, Y181C, Y188L, and K103N–Y181C HIV-1 strains. Six racemic mixtures, 8, 23–25, 31, and 33, were separated at semipreparative level into their pure enantiomers. The (R)-8 enantiomer bearing the chiral (α-methylbenzyl) was superior to the (S)-counterpart. IAS derivatives bearing the (S) alanine unit, (S)-23, (S,R)-25, (S)-31, and (S)-33, were remarkably more potent than the corresponding (R)-enantiomers. Compound 23 protected hippocampal neuronal cells from the excitotoxic insult, while efavirenz (EFV) did not contrast the neurotoxic effect of glutamate. The present results highlight the chiral IASs as new NNRTIs with improved resistance profile against the mutant HIV-1 strains and reduced neurotoxic effects

3-Aroyl-1,4-diarylpyrroles inhibit chronic myeloid leukemia cell growth through an interaction with tubulin

We designed 3-aroyl-1,4-diarylpyrrole (ARDAP) derivatives as potential anticancer agents having different substituents at the 1- or 4-phenyl ring. ARDAP compounds exhibited potent inhibition of tubulin polymerization, binding of colchicine to tubulin, and cancer cell growth. ARDAP derivative 10 inhibited the proliferation of BCR/ABL-expressing KU812 and LAMA84 cells from chronic myeloid leukemia (CML) patients in blast crisis and of hematopoietic cells ectopically expressing the imatinib mesylate (IM)-sensitive KBM5-WT or its IM-resistant KBM5-T315I mutation. Compound 10 minimally affected the proliferation of normal blood cells, indicating that it may be a promising agent to overcome broad tyrosine kinase inhibitor resistance in relapsed/refractory CML patients. Compound 10 significantly decreased CML proliferation by inducing G2/M phase arrest and apoptosis via a mitochondria-dependent pathway. ARDAP 10 augmented the cytotoxic effects of IM in human CML cells. Compound 10 represents a robust lead compound to develop tubulin inhibitors with potential as novel treatments for CML