RESUMO
BACKGROUND: Despite its relatively low incidence, pancreatic ductal adenocarcinoma (PDAC) is a leading cause of cancer deaths because of the aggressive growth/metastasis of the tumor, the lack of early symptoms, and the poor treatment options. Basic research to identify potential therapeutic targets for PDAC is greatly needed. METHODS: We used a negative-selection genome-wide CRISPR screen to identify essential genes in the PANC-1 human pancreatic carcinoma cell line. We validated the top hits with follow-up siRNA screens, using the HPNE, HPAF-II, AsPC-1, and Mia PaCa-2 cell lines. RESULTS: The PSMA6 gene was an identified candidate hit after the CRISPR screen, siRNA validation screen, and siRNA deconvolution screen. Spheroid formation assays and flow cytometry analysis showed that PSMA6 is critical for survival in many pancreatic ductal carcinoma cell models. Lastly, as PSMA6 protein is a proteosomal subunit of the 20S core complex, we showed that bortezomib, a proteasome inhibitor, was especially toxic in PANC-1 cells. CONCLUSIONS: Further study of PSMA6 and the proteasome subunit that it encodes, along with other hits identified in our CRISPR screens, may provide valuable insights into potential therapeutic targets for PDAC.
Assuntos
Carcinoma Ductal Pancreático/genética , Oncogenes/genética , Neoplasias Pancreáticas/genética , Complexo de Endopeptidases do Proteassoma/genética , Bortezomib/farmacologia , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Genoma Humano/genética , Genômica/métodos , Humanos , Pâncreas/patologia , Neoplasias Pancreáticas/patologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Complexo de Endopeptidases do Proteassoma/farmacologia , Inibidores de Proteassoma/farmacologia , RNA Interferente Pequeno/genética , Esferoides CelularesRESUMO
Muscle differentiation is a complex process in which muscle progenitor cells undergo determination and eventually cellular fusion. This process is heavily regulated by such master transcription factors as MYOD and members of the MEF2 family. Here, we show that the transcription factor ZNF148 plays a direct role in human muscle cell differentiation. Downregulation of ZNF148 drives the formation of a muscle phenotype with rapid expression of myosin heavy chain, even in proliferative conditions. This phenotype was most likely mediated by the robust and swift upregulation of MYOD and MEF2C.
Assuntos
Diferenciação Celular , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Músculo Esquelético , Mioblastos/citologia , Mioblastos/metabolismo , Fatores de Transcrição/metabolismo , Diferenciação Celular/genética , Linhagem Celular , Linhagem Celular Transformada , Proteínas de Ligação a DNA/genética , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Desenvolvimento Muscular/genética , Músculo Esquelético/metabolismo , Proteína MyoD/genética , Proteína MyoD/metabolismo , Fenótipo , RNA Interferente Pequeno/genética , Fatores de Transcrição/genéticaRESUMO
INTRODUCTION: The liver plays a central role in transforming and clearing foreign substances. The continuous exposure of the liver to xenobiotics sometimes leads to impaired liver function, referred to as drug-induced liver injury (DILI). The pregnane X receptor (PXR) tightly regulates the expression of genes in the hepatic drug-clearance system and its undesired activation plays a role in DILI. AREAS COVERED: This review focuses on the recent progress in understanding PXR-mediated DILI and highlights the efforts made to assess and manage PXR-mediated DILI during drug development. EXPERT OPINION: Future efforts are needed to further elucidate the mechanisms of PXR-mediated liver injury, including the epigenetic regulation and polymorphisms of PXR. Novel in vitro models containing functional PXR could improve our ability to predict and assess DILI during drug development. PXR inhibitors may provide chemical tools to validate the potential of PXR as a therapeutic target and to develop drugs to be used in the clinic to manage PXR-mediated DILI.