RESUMO
The A-type Aurora kinase is upregulated in many human cancers, and it stabilizes MYC-family oncoproteins, which have long been considered an undruggable target. Here, we describe the design and synthesis of a series of pyrimidine-based derivatives able to inhibit Aurora A kinase activity and reduce levels of cMYC and MYCN. Through structure-based drug design of a small molecule that induces the DFG-out conformation of Aurora A kinase, lead compound 13 was identified, which potently (IC50 < 200 nM) inhibited the proliferation of high-MYC expressing small-cell lung cancer (SCLC) cell lines. Pharmacokinetic optimization of 13 by prodrug strategies resulted in orally bioavailable 25, which demonstrated an 8-fold higher oral AUC (F = 62.3%). Pharmacodynamic studies of 25 showed it to effectively reduce cMYC protein levels, leading to >80% tumor regression of NCI-H446 SCLC xenograft tumors in mice. These results support the potential of 25 for the treatment of MYC-amplified cancers including SCLC.
Assuntos
Aurora Quinase A/antagonistas & inibidores , Desenho de Fármacos , Inibidores de Proteínas Quinases/síntese química , Proteínas Proto-Oncogênicas c-myc/metabolismo , Pirimidinas/química , Animais , Aurora Quinase A/metabolismo , Aurora Quinase B/antagonistas & inibidores , Aurora Quinase B/metabolismo , Sítios de Ligação , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos ICR , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/metabolismo , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
A major obstacle to nanodrugs-mediated cancer therapy is their rapid uptake by the reticuloendothelial system that decreases the systemic exposure of the nanodrugs to tumors and also increases toxicities. Intralipid has been shown to reduce nano-oxaliplatin-mediated toxicity while improving bioavailability. Here, we have found that Intralipid reduces the cytotoxicity of paclitaxel for human monocytic cells, but not for breast, lung, or pancreatic cancer cells. Intralipid also promotes the polarization of macrophages to the anti-cancer M1-like phenotype. Using a xenograft breast cancer mouse model, we have found that Intralipid pre-treatment significantly increases the amount of paclitaxel reaching the tumor and promotes tumor apoptosis. The combination of Intralipid with half the standard clinical dose of Abraxane reduces the tumor growth rate as effectively as the standard clinical dose. Our findings suggest that pre-treatment of Intralipid has the potential to be a powerful agent to enhance the tumor cytotoxic effects of Abraxane and to reduce its off-target toxicities.