RESUMO
Endometrial cancer (EC) often exhibit aberrant activation of PI3K/Akt/mTOR signaling and targeted therapies using mTOR inhibitors showed limited success. The epigenetic modifier, lysine-specific histone demethylase-1A (KDM1A/LSD1) is overexpressed in EC, however, the mechanistic and therapeutic implications of KDM1A in EC are poorly understood. Here, using 119 FDA-approved drugs screen, we identified that KDM1A inhibition is highly synergistic with mTOR inhibitors. Combination therapy of KDM1A and mTOR inhibitors potently reduced the cell viability, survival, and migration of EC cells. Mechanistic studies demonstrated that KDM1A inhibition attenuated the activation of mTOR signaling cascade and abolished rapamycin induced feedback activation of Akt. RNA-seq analysis identified that KDM1A inhibition downregulated the expression of genes involved in rapamycin induced activation of Akt, including the mTORC2 complex. Chromatin immunoprecipitation experiments confirmed KDM1A recruitment to the promoter regions of mTORC2 complex genes and that KDM1A inhibition promoted enrichment of repressive H3K9me2 marks at their promoters. Combination therapy of KDM1A inhibitor and rapamycin reduced the tumor growth in EC xenograft and patient derived xenograft models in vivo and patient derived tumor explants ex vivo. Importantly, in silico analysis of TCGA EC patients data sets revealed that KDM1A expression positively correlated with the levels of PI3K/Akt/mTOR genes. Collectively, our results provide compelling evidence that KDM1A inhibition potentiates the activity of mTOR inhibitors by attenuating the feedback activation of Akt survival signaling. Furthermore, the use of concurrent KDM1A and mTOR inhibitors may be an attractive targeted therapy for EC patients.
Assuntos
Neoplasias do Endométrio/tratamento farmacológico , Histona Desmetilases/genética , Inibidores de MTOR/farmacologia , Serina-Treonina Quinases TOR/genética , Animais , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Histona Desmetilases/antagonistas & inibidores , Humanos , Inibidores de MTOR/química , Masculino , Camundongos , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Limited availability and use of whole blood (WB) following trauma is driven by perceptions that hemostatic function is limited by platelet dysfunction within 5 days storage. We sought to define the hemostatic function of WB stored at 4°C for up to 25 days, elucidate changes in metabolic parameters and mitochondrial dysfunction in platelets in WB, and the effect of supplementation using resveratrol (Res) or cytochrome c (Cyt c). METHODS: Whole blood was collected, aliquoted, and stored at 4°C without agitation. Resveratrol or Cyt c was supplemented before storage, or 10 days post-storage. Serial samples were collected and analyzed for hemostatic function by platelet mapping thromboelastography. Platelets isolated from WB were counted and mitochondrial function assessed by oxygen consumption, mitochondrial membrane potential, and biochemical parameters. RESULTS: Platelet function of WB was maintained up to 15 days at 4°C before a significant decrease was observed at 25 days. Resveratrol or Cyt c improved WB aggregation potential when supplemented 10 days post-storage. Platelet oxygen consumption was maintained until 10-day storage but significantly decreased thereafter in the absence of change in platelet count. Cytochrome c increased oxygen consumption on Day 15 and platelet mitochondrial membrane potential steadily decreased over time, an effect attenuated by Res or Cyt c supplementation 10 days post-storage. Potassium and lactate levels increased during storage, while pH levels decreased, with no observed effect following Res or Cyt c supplementation. CONCLUSION: Storing cold WB with Res or Cyt c supplementation enhances ex vivo aggregation by improving platelet function, thereby extending overall storage life. These findings have potential significance for improving WB availability in immediate trauma situations, including treatment in a battlefield trauma setting. LEVEL OF EVIDENCE: Translational study, diagnostic test or criteria, level II.