RESUMO
KRASG12C inhibitors have revolutionized the clinical management of patients with KRASG12C-mutant lung adenocarcinoma. However, patient exposure to these inhibitors leads to the rapid onset of resistance. In this study, we have used genetically engineered mice to compare the therapeutic efficacy and the emergence of tumor resistance between genetic ablation of mutant Kras expression and pharmacological inhibition of oncogenic KRAS activity. Whereas Kras ablation induces massive tumor regression and prevents the appearance of resistant cells in vivo, treatment of KrasG12C/Trp53-driven lung adenocarcinomas with sotorasib, a selective KRASG12C inhibitor, caused a limited antitumor response similar to that observed in the clinic, including the rapid onset of resistance. Unlike in human tumors, we did not observe mutations in components of the RAS-signaling pathways. Instead, sotorasib-resistant tumors displayed amplification of the mutant Kras allele and activation of xenobiotic metabolism pathways, suggesting that reduction of the on-target activity of KRASG12C inhibitors is the main mechanism responsible for the onset of resistance. In sum, our results suggest that resistance to KRAS inhibitors could be prevented by achieving a more robust inhibition of KRAS signaling mimicking the results obtained upon Kras ablation.
Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Animais , Camundongos , Adenocarcinoma de Pulmão/patologia , Neoplasias Pulmonares/patologia , Mutação , Oncogenes , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Transdução de SinaisRESUMO
Five-year survival for pancreatic ductal adenocarcinoma (PDAC) patients remains below 7% due to the lack of effective treatments. Here, we report that combined ablation of EGFR and c-RAF expression results in complete regression of a significant percentage of PDAC tumors driven by Kras/Trp53 mutations in genetically engineered mice. Moreover, systemic elimination of these targets induces toxicities that are well tolerated. Response to this targeted therapy correlates with transcriptional profiles that resemble those observed in human PDACs. Finally, inhibition of EGFR and c-RAF expression effectively blocked tumor progression in nine independent patient-derived xenografts carrying KRAS and TP53 mutations. These results open the door to the development of targeted therapies for PDAC patients.
Assuntos
Carcinoma Ductal Pancreático/tratamento farmacológico , Receptores ErbB/metabolismo , Cloridrato de Erlotinib/farmacologia , Gefitinibe/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-raf/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Carcinoma Ductal Pancreático/enzimologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas c-raf/genética , Proteínas Proto-Oncogênicas c-raf/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Transdução de Sinais , Carga Tumoral/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Pediatric Acute Megakaryoblastic Leukemia not associated to Down Syndrome (non-DS AMKL) is a rare disease with a dismal prognosis. Around 15% of patients carry the chromosomal translocation t(1;22) that originates the fusion oncogene RBM15-MKL1, which is linked to an earlier disease onset (median of 6months of age) and arises in utero. Here we report the generation of two hPSC cell lines constitutively expressing the oncogene RBM15-MKL1, resulting in an increased expression of known RBM15-MKL1 gene targets. These cell lines represent new disease models of pediatric AMKL to study the impact of the RBM15-MKL1 oncogene on human embryonic hematopoietic development.
