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International audience; A simple and eco-friendly route to gold-NHC complexes bearing different thiosugars is reported. The reaction between [Au(NHC)Cl] precursors, the thiosugars and a weak base proceeds under air using technical grade acetone under mild conditions (60 °C, 1h). The one-pot synthesis of the same complexes starting from the corresponding imidazolium salts was also investigated. The obtained complexes showed strong cytotoxic activities against selected cancer cell lines with IC50 values in the submicromolar to low micromolar concentration range.

International audience; Selective imaging of cellular organelles is a rapidly expanding field of research. Within this context we describe the development of two novel profluorescent probes, MitoP-2 and MitoP-3, for the precise staining of mitochondrial compartments. Herein, we demonstrate that caged, non-fluorescent styryl-benzothiazole probes harbouring a p-nitrobenzyl motif can be converted into their parent fluorophore under the action of the nitroreductase (NTR) enzyme. Two probes, MitoP-2 and MitoP-3, exhibited a turn-ON fluorescence signalling in NTR enzymatic assays. In addition, they also proved successful in the staining of the mitochondria in cellular experiments under normoxic conditions. Interestingly, while MitoP-2 and MitoP-3 structures only differ by the presence of a cationic mitochondrial-targeting unit, both were equally efficient in the staining of mitochondria. Hence, an activity-based approach (MitoP-2) is sufficient for the precise targeting of mitochondria and the use of cationic mitochondria-targeting units (phosphonium present on MitoP-3) can be considered superfluous in this case.

International audience; The presence of amyloid plaques predisposes clinical symptoms of cognitive impairment, which occurs much earlier than other clinical symptoms and plays a crucial role in the neuropathology of AD. Thus, developing probes for Aβ species imaging could be used for early diagnosis of AD, and blocking the initial steps of Aβ aggregation with small molecules has emerged as a valid disease-modifying therapy for Aβ. Herein, we report the design, synthesis and evaluation of a series of new theranostic agents, which can simultaneously perform near infra-red imaging of Aβ plaques, prevent self-aggregation of Aβ monomer, disaggregate preformed Aβ fibrils and play a protective effect on the toxicity of human neuroblastoma cells (SHSY5Y) induced by Aβ1–42. Most of these probes displayed maximum emission in PBS (>650 nm), which falls in the good range for NIRF probes. Importantly, these probes are found to have a high binding affinity toward Aβ aggregates, to exhibit a large fluorescence enhancement upon interaction with Aβ aggregates accompanied by a blueshift in the emission spectra of 20–40 nm and to show an excellent targeting ability for Aβ plaques in slices of brain and eye containing retina tissue from double transgenic mice. These molecules show a promising potential as theranostic agents for the diagnosis and therapy of AD.

A series of 1,3,5-triazinic inhibitors of focal adhesion kinase (FAK) has recently been shown to exert antiangiogenic activity against HUVEC cells and anticancer efficacy against several cancer cell lines. In this report, we designed and synthesized a series of new compounds containing a 1,2,4-triazine core as novel scaffold for FAK inhibitors. These compounds displayed 10-7M IC50 values, and the best one showed IC50 value of 0.23μM against FAK enzymatic activity. Among them, several inhibitors potently inhibited the proliferation of glioblastoma (U-87MG) and colon (HCT-116) cancer cell lines. Docking of compound 10 into the active site of the FAK kinase was performed to explore its potential binding mode.

Early detection of Alzheimer’s disease (AD) is imperative in enabling the understanding and clinical treatment of this disorder, as well as in preventing its progression. Imaging agents specifically targeting Aβ plaques in the brain and the retina may lead to the early diagnosis of AD. Among them, near-infrared fluorescent (NIRF) imaging has emerged as an attractive tool to noninvasively identify and monitor diseases during the preclinical and early stages. In the present study, we report the design, synthesis, and evaluation of a series of new near-infrared fluorescent probes. Most of these probes displayed maximum emission in PBS (>650 nm), which falls in the good range for NIRF probes. Among them, 4a1 showed the highest affinity toward Aβ aggregates (Kd = 7.5 nM) and an excellent targeting ability for Aβ plaques in slices of brain and retina tissue from double transgenic mice. These compounds are also found to effectively prevent Aβ fibril formation and disaggregate preformed Aβ fibrils, showing a prom...

GAPDH is emerging as a key player in T cell development and function. To investigate the role of GAPDH in T cells, we generated a transgenic mouse model overexpressing GAPDH in the T cell lineage. Aged mice developed a peripheral Tfh-like lymphoma that recapitulated key molecular, pathological, and immunophenotypic features of human angioimmunoblastic T cell lymphoma (AITL). GAPDH induced non-canonical NF-κB pathway activation in mouse T cells, which was strongly activated in human AITL. We developed a NIK inhibitor to reveal that targeting the NF-κB pathway prolonged AITL-bearing mouse survival alone and in combination with anti-PD-1. These findings suggest the therapeutic potential of targeting NF-κB signaling in AITL and provide a model for future AITL therapeutic investigations.

International audience; We report the development of four novel fluorescent probes to monitor the activity of the β-galactosidase enzyme (β-gal), in vitro and in living cells. The fluorophores are based on a 6-amino-styryl-benzothiazole push-pull core and display a strong ICT emission. The probes encompass the fluorescent motif that is connected to a β-D-galactopyranoside moiety through a self-immolative benzyl carbamate linker (βGal-1-4). The screening of four different fluorophores enabled us to access new light-up and two-band ratiometric reporters. The four probes, βGal-1-4, exhibited an extremely fast response and over 200-fold fluorescence enhancement (βGal-1) following the enzymatic cleavage of the β-D-galactopyranoside unit. This rapid and extremely sensitive response allowed the detection of senescence-associated β-galactosidase (SA-β-gal) activity; a widely used biomarker of senescence. More importantly, βGal-1 also enabled us to monitor, in real-time, the emergence of senescence in live cells, i.e. the phenotypic transformation from normal to senescent cell. These findings underpin the fact that βGal-1 may find useful applications in biomedical research. Importantly, βGal-1 is suitable for epifluorescence and confocal microscopies, and flow cytometry techniques; which are among the most common analytical tools in biology.

A series of triazinic inhibitors of focal adhesion kinase (FAK) have been recently shown to exert antiangiogenic activity against HUVEC cells and anticancer efficacy against several cancer cell lines. We report herein that we further explored the heterocyclic core of these inhibitors by a fused imidazole ring with the triazine to provide imidazo[1,2-a][1,3,5]triazines. Importantly, these new compounds displayed 10(-7)-10(-8) M IC50 values, and the best inhibitor showed IC50 value of 50 nM against FAK enzymatic activity. Several inhibitors potently inhibited the proliferation of a panel of cancer cell lines expressing high levels of FAK. Apoptosis analysis in U87-MG and HCT-116 cell lines suggested that these compounds delayed cell cycle progression by arresting cells in the G2/M phase of the cell cycle, retarding cell growth. Further investigation demonstrated that these compounds strongly inhibited cell-matrix adhesion, migration, and invasion of U87-MG cells.

We report herein the synthesis of novel diarylamino-1,3,5-triazine derivatives as FAK (focal adhesion kinase) inhibitors and the evaluation of their anti-angiogenic activity on HUVEC cells. Generally, the effects of these compounds on endothelial cells could be correlated with their kinase inhibitory activity. The most efficient compounds displayed inhibition of viability against HUVEC cells in the micromolar range, as observed with TAE-226, which was designed by Novartis Pharma AG. X-ray crystallographic analysis of the co-crystal structure for compound 34 revealed that the mode of interaction with the FAK kinase domain is highly similar to that observed in the complex of TAE-226.

A rapid and efficient Pd-catalyzed aryl and heteroarylamination under microwave irradiation has been developed for various tri-substituted triazines that can serve as versatile building blocks for both supramolecular and medicinal chemistry research. Particularly valuable features of this method included the short reaction time, good yield, and convenient operation.

International audience; Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) emerges as one of the most-promising experimental cancer therapeutic drugs and is currently being tested in clinical trials. However, both intrinsic and acquired resistance of human cancer cells to TRAIL-induced apoptosis poses a huge problem in establishing clinically efficient TRAIL therapies. To assess the regulation of TRAIL-resistance in human pancreatic cancer cells, we studied the TRAIL resistant pancreatic cell line PANC-1. We show that treatment with PH11, a novel Focal Adhesion Kinase (FAK) inhibitor in association with TRAIL rapidly induces apoptosis in TRAIL-resistant PANC-1 cells, but not in normal human fibroblast cells. To explain sensitization, we showed that PH11 restores TRAIL apoptotic pathway in PANC-1 cells through down-regulation of c-FLIP via inhibition of FAK and the phosphatidylinositol-3 kinase (PI3K)/AKT pathways. These findings suggest that this combined treatment may offer an attractive therapeutic strategy for safely and efficiently treating pancreatic cancer.

An efficient and practical procedure was developed to prepare novel 2-(arylmethyl)amino-4-arylamino-6-alkyl-1,3,5-triazines, starting from dicyandiamide and the corresponding arylamines under microwave irradiation and its scope is demonstrated with a number of examples. The valuable feature of this procedure included the short reaction times, high yields, and easy operation.

Compound (Ia) is found to show significant decrease of autophosphorylation of FAK in HUVEC cells.

FAK and FGFR2 signaling pathways play important roles in cancer development, progression and tumor angiogenesis. PHM16 is a novel ATP competitive inhibitor of FAK and FGFR2. To evaluate the therapeutic efficacy of this agent, we examined its anti-angiogenic effect in HUVEC and its anti-tumor effect in different cancer cell lines. We showed PHM16 inhibited endothelial cell viability, adherence and tube formation along with the added ability to induce endothelial cell apoptosis. This compound significantly delayed tumor cell growth. Together, these data showed that inhibition of both FAK and FGFR2 signaling pathways can enhance anti-tumor and anti-angiogenic activities.

A rapid and efficient Pd-catalyzed aryl and heteroarylamination under microwave irradiation has been developed for various tri-substituted triazines that can serve as versatile building blocks for both supramolecular and medicinal chemistry research. Particularly valuable features of this method included the short reaction time, good yield, and convenient operation.

A three-step sequence is developed for the conversion of dicyandiamide and arylamines into the title compounds (VII).

Association of glucocorticoid (GR) and progesterone (PR) receptors with a set of molecular chaperones, including the 90-kDa heat shock protein (hsp90), is a dynamic process required for proper folding and maintaining these nuclear receptors under a transcriptionally inactive, ligand-responsive state. Mutational studies of the chicken hsp90 complementary DNA suggested that three regions of this protein (A, B, and Z) interact with the hormone-binding domain of GR, whereas region A is dispensable for hsp90 binding to PR. We found that this 69-amino acid region can be narrowed down to a 35-mer α-helical, acidic peptide, which is by itself able to inhibit hsp90 association to GR translated in vitro. The hsp90-free GR did not bind ligand, but was devoid of any specific DNA-binding activity, and higher peptide concentrations specifically inhibited the binding of activated GR to DNA. When overexpressed in cultured cells, this peptide acted as an antiglucocorticoid and inhibited the antiactivating protein-1 activity and the ligand-dependent nuclear transfer of GR. None of these effects, either in vivo and in vitro, was observed for PR. The region from residue 232 to residue 265 of hsp90 is, therefore, a domain critical for its association to GR, an association that is a prerequisite for receptor transcriptional activity. More importantly, these results demonstrate that targeting specific protein/protein interaction interfaces is a powerful means to specifically modulate nuclear receptor signaling pathways in a ligand-independent manner.