RESUMO
A series of new prodrugs of daunorubicin and doxorubicin which are candidates for antibody-directed enzyme prodrug therapy (ADEPT) is reported. These compounds (25a,b,c and 32a,b,c) have been designed to generate cytotoxic drugs after activation with beta-glucuronidase. As expected, recovery of the active drug was observed after enzymatic cleavage by Escherichia coli beta-glucuronidase as well as by a fusion protein which has been obtained from human beta-glucuronidase and humanized CEA-specific binding region. The six prodrugs are highly stable and are more than 100-fold less cytotoxic than doxorubicin against murine L1210 cell lines. The ortho-substituted phenyl carbamates 25a,b,c are better substrates for beta-glucuronidase than the corresponding para-substituted analogues. After taking into account additional factors such as stability in plasma and kinetics of enzymatic cleavage, we selected the o-nitro prodrug 25c for clinical trials.
Assuntos
Antibióticos Antineoplásicos/síntese química , Anticorpos Monoclonais/farmacologia , Daunorrubicina/química , Doxorrubicina/análogos & derivados , Doxorrubicina/química , Glucuronatos/síntese química , Pró-Fármacos/síntese química , Animais , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/metabolismo , Antibióticos Antineoplásicos/farmacologia , Anticorpos Monoclonais/imunologia , Antígeno Carcinoembrionário/genética , Antígeno Carcinoembrionário/imunologia , Divisão Celular/efeitos dos fármacos , Daunorrubicina/farmacologia , Doxorrubicina/síntese química , Doxorrubicina/metabolismo , Doxorrubicina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Estabilidade de Medicamentos , Escherichia coli/enzimologia , Glucuronatos/química , Glucuronatos/metabolismo , Glucuronatos/farmacologia , Glucuronidase/genética , Glucuronidase/farmacologia , Humanos , Hidrólise , Fragmentos Fab das Imunoglobulinas/genética , Fragmentos Fab das Imunoglobulinas/imunologia , Cinética , Leucemia L1210/patologia , Camundongos , Pró-Fármacos/química , Pró-Fármacos/metabolismo , Pró-Fármacos/farmacologia , Ratos , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/farmacologia , Relação Estrutura-Atividade , Células Tumorais CultivadasRESUMO
New prodrugs of daunorubicin, 1c, 1e and 2c, including a galactopyranosyl residue linked to the N-3' of the daunosaminyl moiety through substituted o- or p-benzyloxycarbonyl groups were synthesized. Their low cytotoxicity and high stability in plasma fulfil the conditions for antibody-directed enzyme prodrug therapy (ADEPT). Enzymatic hydrolysis using alpha-D-galactosidase gives rise to daunorubicin by subsequent self-elimination of the spacers. However, elimination clearly depends on the aromatic substitution pattern, as demonstrated especially by comparison with non-substituted analogues.
