RESUMO
PURPOSE: Protein kinases are known to play a prominent role in oncogenic progression across multiple cancer subtypes, yet their role in prostate cancer progression remains underexplored. The purpose of this study was to identify kinases that drive prostate cancer progression.Experimental Design: To discover kinases that drive prostate cancer progression, we investigated the association between gene expression of all known kinases and long-term clinical outcomes in tumor samples from 545 patients with high-risk disease. We evaluated the impact of genetic and pharmacologic inhibition of the most significant kinase associated with metastatic progression in vitro and in vivo. RESULTS: DNA-dependent protein kinase (DNAPK) was identified as the most significant kinase associated with metastatic progression in high-risk prostate cancer. Inhibition of DNAPK suppressed the growth of both AR-dependent and AR-independent prostate cancer cells. Gene set enrichment analysis nominated Wnt as the top pathway associated with DNAPK. We found that DNAPK interacts with the Wnt transcription factor LEF1 and is critical for LEF1-mediated transcription. CONCLUSIONS: Our data show that DNAPK drives prostate cancer progression through transcriptional regulation of Wnt signaling and is an attractive therapeutic target in aggressive prostate cancer.
Assuntos
Proteína Quinase Ativada por DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Transcrição Gênica , Via de Sinalização Wnt , Animais , Biomarcadores Tumorais , Linhagem Celular Tumoral , Movimento Celular , Proteína Quinase Ativada por DNA/antagonistas & inibidores , Proteína Quinase Ativada por DNA/genética , Modelos Animais de Doenças , Progressão da Doença , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Masculino , Camundongos , Metástase Neoplásica , Fenótipo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Ligação Proteica , RNA Interferente Pequeno/genéticaRESUMO
DNA methylation can regulate gene expression and has been shown to modulate cancer cell biology and chemotherapy resistance. Therapeutic radiation results in a biological response to counter the subsequent DNA damage and genomic stress in order to avoid cell death. In this study, we analyzed DNA methylation changes at>450,000 loci to determine a potential epigenetic response to ionizing radiation in MDA-MB-231 cells. Cells were irradiated at 2 and 6 Gy and analyzed at 7 time points from 1-72 h. Significantly differentially methylated genes were enriched in gene ontology categories relating to cell cycle, DNA repair, and apoptosis pathways. The degree of differential methylation of these pathways varied with radiation dose and time post-irradiation in a manner consistent with classical biological responses to radiation. A cell cycle arrest was observed 24 h post-irradiation and DNA damage, as measured by γH2AX, resolved at 24 h. In addition, cells showed low levels of apoptosis 2-48 h post-6 Gy and cellular senescence became significant at 72 h post-irradiation. These DNA methylation changes suggest an epigenetic role in the cellular response to radiation.