RESUMO
Lithium is an effective mood stabilizer that has been clinically used to treat bipolar disorder for several decades. Recent studies have suggested that lithium possesses robust neuroprotective and anti-tumor properties. Thus far, a large number of lithium targets have been discovered. Here, we report for the first time that HDAC1 is a target of lithium. Lithium significantly down-regulated HDAC1 at the translational level by targeting HDAC1 mRNA. We also showed that depletion of HDAC1 is essential for the neuroprotective effects of lithium and for the lithium-mediated degradation of mutant huntingtin through the autophagic pathway. Our studies explain the multiple functions of lithium and reveal a novel mechanism for the function of lithium in neurodegeneration.
Assuntos
Histona Desacetilase 1/antagonistas & inibidores , Histona Desacetilase 1/genética , Lítio/farmacologia , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Autofagia , Proteínas CELF1 , Regulação para Baixo/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Células HEK293 , Células HeLa , Histona Desacetilase 1/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Humanos , Proteína Huntingtina , Fármacos Neuroprotetores/farmacologia , Proteólise/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismoRESUMO
Aberrant JAK/STAT3 pathway has been reported to be related to hepatocellular carcinoma (HCC) in many cell lines. In this study, a double-regulated oncolytic adenovirus vector that can replicate and induce a cytopathic effect in alpha-fetoprotein (AFP)-positive HCC cell lines with p53 dysfunction was successfully constructed. Two therapeutic genes, suppressor of cytokine signaling 3 (SOCS3) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), were chosen and incorporated into this vector system, respectively. The combined treatment of AFP-D55-SOCS3 and AFP-D55-TRAIL (2:3 ratio) exhibited potent antitumor activity in AFP-positive HCC cell lines compared with any other treatment both in vitro and in vivo. Specific replication and low progeny yield in AFP-positive HCC cell lines rendered these double-regulated oncolytic adenoviruses remarkably safe. Our data demonstrated that restoration of SOCS3, which inhibits the JAK/STAT3 pathway, by AFP-D55-SOCS3 not only could antagonize HCC therapeutic resistance to TRAIL and adenoviruses, but could also induce cell cycle arrest in HCC cell lines. SOCS3 could down-regulate Cyclin D1 and anti-apoptotic proteins such as XIAP, Survivin, Bcl-xL, and Mcl-1, which are responsible for the synergistic inhibitory effects of AFP-D55-SOCS3 and AFP-D55-TRAIL. Dual gene and double-regulated oncolytic adenoviruses may provide safety and excellent antitumor effects for liver cancer, which is the advantage of a cancer-targeting gene virotherapy strategy.