Identification of new aminoacid amides containing the imidazo[2,1-b]benzothiazol-2-ylphenyl moiety as inhibitors of tumorigenesis by oncogenic Met signaling

Discovery and Biological Evaluation of Novel Dual EGFR/c-Met Inhibitors

Activating mutations in the epidermal growth factor receptor (EGFR) have been identified in a subset of non-small cell lung cancer (NSCLC), which is one of the leading cancer types worldwide. Application of EGFR tyrosine kinase inhibitors leads to acquired resistance by secondary EGFR mutations or by amplification of the hepatocyte growth factor receptor (c-Met) gene. Although several EGFR and c-Met inhibitors have been reported, potent dual EGFR/c-Met inhibitors, which can overcome this latter resistance mechanism, have hitherto not been published and have not reached clinical trials. In the present study we have identified dual EGFR/c-Met inhibitors and designed novel N-[4-(quinolin-4-yloxy)-phenyl]-biarylsulfonamide derivatives, which inhibit the c-Met receptor and both the wild-type and the activating mutant EGFR kinases in nanomolar range. We have demonstrated by Western blot analysis that compound 10 inhibits EGFR and c-Met phosphorylation at cellular level and effectively inhibits viability of the NSCLC cell lines.

Carbodiimide Mediated Synthesis of new Thiazolidin-4-Ones and Thiazinan-4-Ones from Thiosemicarbazone Derivatives of 6,7-Dihydro-1H-Indazole-4(5H)-Ones

5,5-Dimethyl-2-[(2-substitutedphenylhydrazinyl)methylene]cyclohexane-1,3-dione, obtained from heating dimedone with N,N‘-dimethylformamide dimethyl acetal (DMF-DMA) and phenyl hydrazines, on cyclisation in ethanol gave 6,7-dihydro-1 H-indazol-4(5 H)-ones. The thiosemicarbazone derivative of 6,7-dihydro-1 H-indazole-4(5 H)-ones, on cyclocondensation with a and (3-haloacids in the presence of N,N‘-dicyclohexylcarbodiimide afforded new thiazolidin-4-ones and 1,3-thiazinan-4-ones respectively. Thiosemicarbazone of 6,7-dihydro-1 H-indazol-4(5 H)-ones on stirring with phenacyl bromides yields 2,4-disubstituted thiazoles. X-ray structure of the intermediate compound 5-dimethyl-2-[(2-phenylhydrazinyl)methylene] cyclohexane-1,3-dione was determined.

Quinazolinecarboline alkaloid evodiamine as scaffold for targeting topoisomerase I and sirtuins

This paper reports the synthesis of a series of evodiamine derivatives. We assayed the ability to inhibit cell growth on three human tumour cell lines (H460, MCF-7 and HepG2) and we evaluated the capacity to interfere with the catalytic activity of topoisomerase I both by the relaxation assay and the occurrence of the cleavable complex. Moreover, whose effect on sirtuins 1, 2 and 3 was investigated. Finally, molecular docking analyses were performed in an attempt to rationalize the biological results.

Aminopyridyl/Pyrazinyl Spiro[indoline-3,4'-piperidine]-2-ones As Highly Selective and Efficacious c-Met/ALK Inhibitors

A series of novel aminopyridyl/pyrazinyl-substituted spiro[indoline-3,4'-piperidine]-2-ones were designed, synthesized, and tested in various in vitro/in vivo pharmacological and antitumor assays. 6-[6-Amino-5-[(1R)-1-(2,6-dichloro-3-fluorophenyl)ethoxy]-3-pyridyl]-1'-methylspiro[indoline-3,4'-piperidine]-2-one (compound 5b or SMU-B) was identified as a potent, highly selective, well-tolerated, and orally efficacious c-Met/ALK dual inhibitor, which showed pharmacodynamics effect by inhibiting c-Met phosphorylation in vivo and significant tumor growth inhibitions (>50%) in GTL-16 human gastric carcinoma xenograft models.

Combined drug action of 2-phenylimidazo[2,1-b]benzothiazole derivatives on cancer cells according to their oncogenic molecular signatures

The development of targeted molecular therapies has provided remarkable advances into the treatment of human cancers. However, in most tumors the selective pressure triggered by anticancer agents encourages cancer cells to acquire resistance mechanisms. The generation of new rationally designed targeting agents acting on the oncogenic path(s) at multiple levels is a promising approach for molecular therapies. 2-phenylimidazo[2,1-b]benzothiazole derivatives have been highlighted for their properties of targeting oncogenic Met receptor tyrosine kinase (RTK) signaling. In this study, we evaluated the mechanism of action of one of the most active imidazo[2,1-b]benzothiazol-2-ylphenyl moiety-based agents, Triflorcas, on a panel of cancer cells with distinct features. We show that Triflorcas impairs in vitro and in vivo tumorigenesis of cancer cells carrying Met mutations. Moreover, Triflorcas hampers survival and anchorage-independent growth of cancer cells characterized by "RTK swapping" by interfering with PDGFRβ phosphorylation. A restrained effect of Triflorcas on metabolic genes correlates with the absence of major side effects in vivo. Mechanistically, in addition to targeting Met, Triflorcas alters phosphorylation levels of the PI3K-Akt pathway, mediating oncogenic dependency to Met, in addition to Retinoblastoma and nucleophosmin/B23, resulting in altered cell cycle progression and mitotic failure. Our findings show how the unusual binding plasticity of the Met active site towards structurally different inhibitors can be exploited to generate drugs able to target Met oncogenic dependency at distinct levels. Moreover, the disease-oriented NCI Anticancer Drug Screen revealed that Triflorcas elicits a unique profile of growth inhibitory-responses on cancer cell lines, indicating a novel mechanism of drug action. The anti-tumor activity elicited by 2-phenylimidazo[2,1-b]benzothiazole derivatives through combined inhibition of distinct effectors in cancer cells reveal them to be promising anticancer agents for further investigation.