RESUMO
Building on the preceding structural analysis and a structure-activity relationship (SAR) of 8-aryl-2-hexynyl nucleoside hA2AAR antagonist 2a, we strategically inverted C2/C8 substituents and eliminated the ribose moiety. These modifications aimed to mitigate potential steric interactions between ribose and adenosine receptors. The SAR findings indicated that such inversions significantly modulated hA3AR binding affinities depending on the type of ribose, whereas removal of ribose altered the functional efficacy via hA2AAR. Among the synthesized derivatives, 2-aryl-8-hexynyl adenine 4a demonstrated the highest selectivity for hA2AAR (Ki,hA2A = 5.0 ± 0.5 nM, Ki,hA3/Ki,hA2A = 86) and effectively blocked cAMP production and restored IL-2 secretion in PBMCs. Favorable pharmacokinetic properties and a notable enhancement of anticancer effects in combination with an mAb immune checkpoint blockade were observed upon oral administration of 4a. These findings establish 4a as a viable immune-oncology therapeutic candidate.
Assuntos
Adenina , Antagonistas do Receptor A2 de Adenosina , Nucleosídeos , Receptor A2A de Adenosina , Ribose , Humanos , Relação Estrutura-Atividade , Animais , Adenina/farmacologia , Adenina/química , Adenina/análogos & derivados , Antagonistas do Receptor A2 de Adenosina/farmacologia , Antagonistas do Receptor A2 de Adenosina/química , Antagonistas do Receptor A2 de Adenosina/síntese química , Nucleosídeos/química , Nucleosídeos/farmacologia , Nucleosídeos/síntese química , Ribose/química , Ribose/metabolismo , Receptor A2A de Adenosina/metabolismo , Camundongos , Estrutura Molecular , Ratos , Feminino , Linhagem Celular TumoralRESUMO
MDH1 and MDH2 enzymes play an important role in the survival of lung cancer. In this study, a novel series of dual MDH1/2 inhibitors for lung cancer was rationally designed and synthesized, and their SAR was carefully investigated. Among the tested compounds, compound 50 containing a piperidine ring displayed an improved growth inhibition of A549 and H460 lung cancer cell lines compared with LW1497. Compound 50 reduced the total ATP content in A549 cells in a dose-dependent manner; it also significantly suppressed the accumulation of hypoxia-inducible factor 1-alpha (HIF-1α) and the expression of HIF-1α target genes such as GLUT1 and pyruvate dehydrogenase kinase 1 (PDK1) in a dose-dependent manner. Furthermore, compound 50 inhibited HIF-1α-regulated CD73 expression under hypoxia in A549 lung cancer cells. Collectively, these results indicate that compound 50 may pave the way for the development of next-generation dual MDH1/2 inhibitors to target lung cancer.