RESUMO
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is considered to be a promising anticancer agent because its active form TRAIL trimer is able to induce apoptosis in different tumor cell lines while sparing normal cells. However, TRAIL trimer possesses a short half-life and low stability, which turns out to be a major obstacle for the development of clinical trials. In our present study, we constructed a recombined TRAIL trimer by genetic fusion of non-collagenous domain (NC1) of human collagen XVIII or its trimerization domain (TD) to C-terminus of TRAIL via a flexible linker, and then refolded the fusion proteins using a two-step refolding approach, namely a combination of dilution and gel filtration chromatography. As a result, both recombinant proteins, TRAIL-NC1 and TRAIL-TD, were expressed in Escherichia coli as inclusion bodies, and they exhibited difficultly to refold efficiently by conventional methods. Thereby, we applied a modified two-step refolding approach to refold fusion proteins. More than 55 % of TRAIL-NC1 and 90 % of TRAIL-TD protein activity was recovered during the two-step refolding approach, and their stability was also increased significantly. Also, size exclusion chromatography showed refolded TRAIL-NC1 was a trimer while TRAIL-TD, hexamer. However, both of them exerted good apoptosis activity on NCI-H460 cells.
Assuntos
Colágeno Tipo XVIII/metabolismo , Dobramento de Proteína , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Antineoplásicos/isolamento & purificação , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Apoptose , Linhagem Celular Tumoral , Cromatografia em Gel , Colágeno Tipo XVIII/genética , Colágeno Tipo XVIII/isolamento & purificação , Colágeno Tipo XVIII/farmacologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Escherichia coli/genética , Expressão Gênica , Humanos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/genética , Ligante Indutor de Apoptose Relacionado a TNF/isolamento & purificação , Ligante Indutor de Apoptose Relacionado a TNF/farmacologiaRESUMO
Monomethyl auristatin E (MMAE) is conjugated with TNF-related apoptosis-inducing ligand (TRAIL) via a linker that is stable in extracellular fluid, while it is cleaved by cathepsin once the conjugate has entered a tumor cell, thus activating the antimitotic mechanism of MMAE. The TRAIL-MMAE conjugate is a conceptually viable therapeutic strategy with improved in vitro antitumor activity, cell circle arrest and specific accumulation in tumor to treat TRAIL-resistant tumors.