RESUMO
Thioredoxin 1 (Trx1) and glutaredoxin 1 (Grx1) are two ubiquitous redox enzymes that are central for redox homeostasis but also are implicated in many other processes, including stress sensing, inflammation, and apoptosis. In addition to their enzymatic redox activity, a growing body of evidence shows that Trx1 and Grx1 play regulatory roles via protein-protein interactions with specific proteins, including Ask1. The currently available inhibitors of Trx1 and Grx1 are thiol-reactive electrophiles or disulfides that may suffer from low selectivity because of their thiol reactivity. In this report, we used a phage peptide library to identify a 7-mer peptide, 2GTP1, that binds to both Trx1 and Grx1. We further showed that a cell-permeable derivative of 2GTP1, TAT-2GTP1, disrupts the Trx1-Ask1 interaction, which induces Ask1 phosphorylation with subsequent activation of JNK, stabilization of p53, and reduced viability of cancer cells. Notably, as opposed to a disulfide-derived Trx1 inhibitor (PX-12), TAT-2GTP1 was selective for activating the Ask1 pathway without affecting other stress signaling pathways, such as endoplasmic reticulum stress and AMPK activation. Overall, 2GTP1 will serve as a useful probe for investigating protein interactions of Trx1.
Assuntos
MAP Quinase Quinase Quinase 5/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Oligopeptídeos/farmacologia , Biblioteca de Peptídeos , Estresse Fisiológico/fisiologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Enzimas Imobilizadas , Glutarredoxinas , Células HEK293 , Humanos , MAP Quinase Quinase Quinase 5/química , MAP Quinase Quinase Quinase 5/fisiologia , NADP/análise , Oligopeptídeos/isolamento & purificação , Oxirredução , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Mapeamento de Interação de Proteínas , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/metabolismoRESUMO
Small molecules that block the altered metabolism in cancer or increase the production of reactive oxygen species (ROS) are emerging as potential anti-cancer agents. Considering that various carbohydrates can be used for cellular energetics or protein N-glycosylation of which interruption can lead to cellular stress, we have synthesized and evaluated a library of N-aryl glycosides for induction of ROS and cytotoxicity in H1299 cancer cell line. Two N-aryl glycosides (K8 and H8) were identified that induce about 2-fold induction of ROS and cytotoxicity in H1299 cells. We further showed that the acetylated form of K8 (K8A) activates AMPK, and stabilizes p53 in HEK293 cells, and induce a higher cytotoxicity than 2-deoxy-d-glucose in H1299 cell line.
