RESUMO
EGFR-mutated lung adenocarcinoma patients treated with gefitinib and osimertinib show a therapeutic benefit limited by the appearance of secondary mutations, such as EGFRT790M and EGFRC797S. It is generally assumed that these secondary mutations render EGFR completely unresponsive to the inhibitors, but contrary to this, we uncovered here that gefitinib and osimertinib increased STAT3 phosphorylation (p-STAT3) in EGFRT790M and EGFRC797S tumoral cells. Interestingly, we also found that concomitant Notch inhibition with gefitinib or osimertinib treatment induced a p-STAT3-dependent strong reduction in the levels of the transcriptional repressor HES1. Importantly, we showed that tyrosine kinase inhibitor-resistant tumors, with EGFRT790M and EGFRC797S mutations, were highly responsive to the combined treatment of Notch inhibitors with gefitinib or osimertinib, respectively. Finally, in patients with EGFR mutations treated with tyrosine kinase inhibitors, HES1 protein levels increased during relapse and correlated with shorter progression-free survival. Therefore, our results offer a proof of concept for an alternative treatment to chemotherapy in lung adenocarcinoma osimertinib-treated patients after disease progression.
Assuntos
Acrilamidas/farmacologia , Adenocarcinoma de Pulmão , Compostos de Anilina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Receptores ErbB , Gefitinibe/farmacologia , Neoplasias Pulmonares , Mutação de Sentido Incorreto , Proteínas de Neoplasias , Inibidores de Proteínas Quinases/farmacologia , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Substituição de Aminoácidos , Animais , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Receptores ErbB/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Transgênicos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Fatores de Transcrição HES-1/genética , Fatores de Transcrição HES-1/metabolismoRESUMO
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
A quarter of all solid tumors harbor KRAS oncogenes. Yet, no selective drugs have been approved to treat these malignancies. Genetic interrogation of the MAPK pathway revealed that systemic ablation of MEK or ERK kinases in adult mice prevent tumor development but are unacceptably toxic. Here, we demonstrate that ablation of c-RAF expression in advanced tumors driven by KrasG12V/Trp53 mutations leads to significant tumor regression with no detectable appearance of resistance mechanisms. Tumor regression results from massive apoptosis. Importantly, systemic abrogation of c-RAF expression does not inhibit canonical MAPK signaling, hence, resulting in limited toxicities. These results are of significant relevance for the design of therapeutic strategies to treat K-RAS mutant cancers.
