Sulfamoylated Estradiol Analogs Targeting the Actin and Microtubule Cytoskeletons Demonstrate Anti-Cancer Properties In Vitro and In Ovo.

The microtubule-disrupting agent 2-methoxyestradiol (2-ME) displays anti-tumor and anti-angiogenic properties, but its clinical development is halted due to poor pharmacokinetics. We therefore designed two 2-ME analogs in silico-an ESE-15-one and an ESE-16 one-with improved pharmacological properties. We investigated the effects of these compounds on the cytoskeleton in vitro, and their anti-angiogenic and anti-metastatic properties in ovo.

A novel inhibitor of the mitochondrial respiratory complex I with uncoupling properties exerts potent antitumor activity.

Cancer cells are highly dependent on bioenergetic processes to support their growth and survival. Disruption of metabolic pathways, particularly by targeting the mitochondrial electron transport chain complexes (ETC-I to V) has become an attractive therapeutic strategy. As a result, the search for clinically effective new respiratory chain inhibitors with minimized adverse effects is a major goal.

Affinity selection mass spectrometry speeding drug discovery.

Affinity selection mass spectrometry (AS-MS) has gained momentum in drug discovery. This review summarizes how this technology has slowly risen as a new paradigm in hit identification and its potential synergy with DNA encoded library technology. It presents an overview of the recent results on challenging targets and perspectives on new areas of research, such as RNA targeting with small molecules.

Preclinical Evaluation of a Novel Small Molecule Inhibitor of LIM Kinases (LIMK) CEL_Amide in Philadelphia-Chromosome Positive () Acute Lymphoblastic Leukemia (ALL).

Ph+ () B-ALL was considered to be high risk, but recent advances in -targeting TKIs has shown improved outcomes in combination with backbone chemotherapy. Nevertheless, new treatment strategies are needed, including approaches without chemotherapy for elderly patients. LIMK1/2 acts downstream from various signaling pathways, which modifies cytoskeleton dynamics via phosphorylation of cofilin.

Development of Macrocyclic PRMT5-Adaptor Protein Interaction Inhibitors.

The PRMT5-MEP50 methyltransferase is a major target for anticancer drug discovery, and modulators of its interactions with different regulatory proteins are in high demand because they modulate PRMT5 substrate selectivity. We describe a strategy for the development of a PRMT5/adaptor protein PPI inhibitor, which includes the design and synthesis of macrocyclic peptides based on the motif for the interaction of PRMT5 with its adaptor protein RioK1. After the initial exploration of different macrocycle sizes and cyclization linkages, analysis of a peptide library identified hot spots for the variation of the amino acid structure.

Characterization of Signalling Pathways That Link Apoptosis and Autophagy to Cell Death Induced by Estrone Analogues Which Reversibly Depolymerize Microtubules.

The search for novel anti-cancer compounds which can circumvent chemotherapeutic drug resistance and limit systemic toxicity remains a priority. 2-Ethyl-3--sulphamoyl-estra-1,3,5(10)15-tetraene-3-ol-17one (ESE-15-one) and 2-ethyl-3--sulphamoyl-estra-1,3,5(10)16-tetraene (ESE-16) are sulphamoylated 2-methoxyestradiol (2-ME) analogues designed by our research team. Although their cytotoxicity has been demonstrated in vitro, the temporal and mechanistic responses of the initiated intracellular events are yet to be determined.

Exploring new targets and chemical space with affinity selection-mass spectrometry.

Affinity selection-mass spectrometry (AS-MS) is a high-throughput screening (HTS) technique for drug discovery that enables rapid screening of large collections of compounds to identify ligands for a specific biomolecular target. AS-MS is a binding assay that is insensitive to the functional effects a ligand might have, which is important because it lets us identify novel ligands irrespective of their binding site. This approach is gaining popularity, notably due to its role in the emergence of useful agents for targeted protein degradation.

Synergy of FLT3 inhibitors and the small molecule inhibitor of LIM kinase1/2 CEL_Amide in FLT3-ITD mutated Acute Myeloblastic Leukemia (AML) cells.

Patients with FLT3-ITD mutated (FLT3-ITD+) Acute Myeloid Leukemia (AML), have frequently relapsed or refractory disease and FLT3-ITD+ inhibitors have limited efficacy. Rho kinases (ROCK) are constitutively activated by FLT3-ITD+ in AML via PI3 kinase and Rho GTPase. Upon activation by ROCK, LIM kinases (LIMK) inactivate cofilin by phosphorylation which affects cytoskeleton dynamics, cell growth and apoptosis.

Two Antagonistic Microtubule Targeting Drugs Act Synergistically to Kill Cancer Cells.

Paclitaxel is a microtubule stabilizing agent and a successful drug for cancer chemotherapy inducing, however, adverse effects. To reduce the effective dose of paclitaxel, we searched for pharmaceutics which could potentiate its therapeutic effect. We screened a chemical library and selected Carba1, a carbazole, which exerts synergistic cytotoxic effects on tumor cells grown in vitro, when co-administrated with a low dose of paclitaxel.

Discovery of holoenzyme-disrupting chemicals as substrate-selective CK2 inhibitors.

CK2 is a constitutively active protein kinase overexpressed in numerous malignancies. Interaction between CK2α and CK2β subunits is essential for substrate selectivity. The CK2α/CK2β interface has been previously targeted by peptides to achieve functional effects; however, no small molecules modulators were identified due to pocket flexibility and open shape.

A quantitative proteomic analysis of cofilin phosphorylation in myeloid cells and its modulation using the LIM kinase inhibitor Pyr1.

LIM kinases are located at a strategic crossroad, downstream of several signaling pathways and upstream of effectors such as microtubules and the actin cytoskeleton. Cofilin is the only LIM kinases substrate that is well described to date, and its phosphorylation on serine 3 by LIM kinases controls cofilin actin-severing activity. Consequently, LIM kinases inhibition leads to actin cytoskeleton disorganization and blockade of cell motility, which makes this strategy attractive in anticancer treatments.

Specific Targeting of Plant and Apicomplexa Parasite Tubulin through Differential Screening Using In Silico and Assay-Based Approaches.

Dinitroanilines are chemical compounds with high selectivity for plant cell α-tubulin in which they promote microtubule depolymerization. They target α-tubulin regions that have diverged over evolution and show no effect on non-photosynthetic eukaryotes. Hence, they have been used as herbicides over decades.

LIM kinases: cofilin and beyond.

LIM kinases are common downstream effectors of several signalization pathways and function as a signaling node that controls cytoskeleton dynamics through the phosphorylation of the cofilin family proteins. These last 10 years, several reports indicate that the functions of LIM kinases are more extended than initially described and, specifically, that LIM kinases also control microtubule dynamics, independently of their regulation of actin microfilament. In this review we analyze the data supporting these conclusions and the possible mechanisms that could be involved in the control of microtubules by LIM kinases.

LIM Kinase Inhibitor Pyr1 Reduces the Growth and Metastatic Load of Breast Cancers.

LIM kinases (LIMK) are emerging targets for cancer therapy, and they function as network hubs to coordinate actin and microtubule dynamics. When LIMKs are inhibited, actin microfilaments are disorganized and microtubules are stabilized. Owing to their stabilizing effect on microtubules, LIMK inhibitors may provide a therapeutic strategy to treat taxane-resistant cancers.

Novel in silico-designed estradiol analogues are cytotoxic to a multidrug-resistant cell line at nanomolar concentrations.

Purpose: 2-Methoxyestradiol (2ME) is a promising anti-cancer agent that disrupts the integrity and dynamics of the spindle network. In order to overcome the pharmacokinetic constraints of this compound, a panel of sulphamoylated estradiol analogues were in silico-designed by our laboratory. In this study, we analysed the potential of each analogue to induce cell death on a panel of cancer cell lines.

Novel synthetic pharmacophores inducing a stabilization of cellular microtubules.

Microtubule drugs have been widely used in cancer chemotherapies. Although microtubules are subject to regulation by signal transduction mechanisms, their pharmacological modulation has so far relied on compounds that bind to the tubulin subunit. Using a cell-based assay designed to probe the microtubule polymerization status, we identified two pharmacophores, CM09 and CM10, as cell-permeable microtubule stabilizing agents.

[Phenotypic screens or one stone to kill two birds: discover the target and its pharmacological regulator].

Phenotypic screens, in which chemical libraries are assayed on cells with the aim to isolate compounds that interfere with a given cell function, are a risky but powerful strategy to discover, in the same approach, new therapeutic targets and the compounds able to regulate them. With a strong experience of nearly 10 years in the field, we present the advantages of such an approach, the possible troubles and technical solutions. We also present in this paper a french network which has been recently built and that gather all the competencies needed for screening approaches.

Sulphamoylated 2-methoxyestradiol analogues induce apoptosis in adenocarcinoma cell lines.

2-Methoxyestradiol (2ME2) is a naturally occurring estradiol metabolite which possesses antiproliferative, antiangiogenic and antitumor properties. However, due to its limited biological accessibility, synthetic analogues have been synthesized and tested in attempt to develop drugs with improved oral bioavailability and efficacy. The aim of this study was to evaluate the antiproliferative effects of three novel in silico-designed sulphamoylated 2ME2 analogues on the HeLa cervical adenocarcinoma cell line and estrogen receptor-negative breast adenocarcinoma MDA-MB-231 cells.

Azaindole derivatives are inhibitors of microtubule dynamics, with anti-cancer and anti-angiogenic activities.

Background And Purpose: Drugs targeting microtubules are commonly used for cancer treatment. However, the potency of microtubule inhibitors used clinically is limited by the emergence of resistance. We thus designed a strategy to find new cell-permeable microtubule-targeting agents.

Pharmacological inhibition of LIM kinase stabilizes microtubules and inhibits neoplastic growth.

The emergence of tumor resistance to conventional microtubule-targeting drugs restricts their clinical use. Using a cell-based assay that recognizes microtubule polymerization status to screen for chemicals that interact with regulators of microtubule dynamics, we identified Pyr1, a cell permeable inhibitor of LIM kinase, which is the enzyme that phosphorylates and inactivates the actin-depolymerizing factor cofilin. Pyr1 reversibly stabilized microtubules, blocked actin microfilament dynamics, inhibited cell motility in vitro and showed anticancer properties in vivo, in the absence of major side effects.

Antitumoral activity of allosteric inhibitors of protein kinase CK2.

Introduction: Due to its physiological role into promoting cell survival and its dysregulation in most cancer cells, protein kinase CK2 is a relevant physiopathological target for development of chemical inhibitors. We report the discovery of azonaphthalene derivatives, as a new family of highly specific CK2 inhibitors. First, we demonstrated that CK2 inhibition (IC50= 0.

Structure-function analysis of the beta regulatory subunit of protein kinase CK2 by targeting embryonic stem cell.

Programs that govern stem cell maintenance and pluripotency are dependent on extracellular factors and of intrinsic cell modulators. Embryonic stem (ES) cells with a specific depletion of the gene encoding the regulatory subunit of protein kinase CK2 (CK2β) revealed a viability defect. However, analysis of CK2β functions along the neural lineage established CK2β as a positive regulator for neural stem/progenitor cell (NSC) proliferation and multipotency.

Antitumor activity of pyridocarbazole and benzopyridoindole derivatives that inhibit protein kinase CK2.

The alkyloid compound ellipticine derived from the berrywood tree is a topoisomerase II poison that is used in ovarian and breast cancer treatment. In this study, we report the identification of ellipticine derivatives and their tetracyclic angular benzopyridoindole analogues as novel ATP-competitive inhibitors of the protein kinase CK2. In vitro and in vivo assays showed that these compounds have a good pharmacologic profile, causing a marked inhibition of CK2 activity associated with cell cycle arrest and apoptosis in human cancer cells.

In vitro and in vivo assays of protein kinase CK2 activity.

Protein kinase CK2 (formerly casein kinase 2) is recognized as a central component in the control of the cellular homeostasis; however, much remains unknown regarding its regulation and its implication in cellular transformation and carcinogenesis. Moreover, study of CK2 function and regulation in a cellular context is complicated by the dynamic multisubunit architecture of this protein kinase. Although a number of robust techniques are available to assay CK2 activity in vitro, there is a demand for sensitive and specific assays to evaluate its activity in living cells.

Functional analysis of the BMP9 response of ALK1 mutants from HHT2 patients: a diagnostic tool for novel ACVRL1 mutations.

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant genetically inheritable vascular dysplasia caused by mutations in genes encoding receptors of the transforming growth factor-beta (TGF-beta) family: ENG, encoding endoglin (HHT1), and ACVRL1, encoding activin receptor-like kinase-1 (ALK1; HHT2). Our recent discovery of bone morphogenetic protein 9 (BMP9) as the specific ligand for ALK1 allowed us to reevaluate the functional significance of ACVRL1 mutations. We generated 19 ALK1 mutants reproducing HHT2 mutations (4 were novel mutations) found throughout the protein.