RESUMO
Diffuse intrinsic pontine glioma (DIPG) is a lethal childhood brainstem tumour, with a quarter of patients harbouring somatic mutations in ACVR1, encoding the serine/threonine kinase ALK2. Despite being an amenable drug target, little has been done to-date to systematically evaluate the role of ACVR1 in DIPG, nor to screen currently available inhibitors in patient-derived tumour models. Here we show the dependence of DIPG cells on the mutant receptor, and the preclinical efficacy of two distinct chemotypes of ALK2 inhibitor in vitro and in vivo. We demonstrate the pyrazolo[1,5-a]pyrimidine LDN-193189 and the pyridine LDN-214117 to be orally bioavailable and well-tolerated, with good brain penetration. Treatment of immunodeprived mice bearing orthotopic xenografts of H3.3K27M, ACVR1R206H mutant HSJD-DIPG-007 cells with 25 mg/kg LDN-193189 or LDN-214117 for 28 days extended survival compared with vehicle controls. Development of ALK2 inhibitors with improved potency, selectivity and advantageous pharmacokinetic properties may play an important role in therapy for DIPG patients.
Assuntos
Receptores de Ativinas Tipo I/genética , Antineoplásicos/farmacologia , Neoplasias do Tronco Encefálico/tratamento farmacológico , Glioma Pontino Intrínseco Difuso/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Piridinas/farmacologia , Pirimidinas/farmacologia , Receptores de Ativinas Tipo I/antagonistas & inibidores , Receptores de Ativinas Tipo I/metabolismo , Administração Oral , Animais , Antineoplásicos/farmacocinética , Apoptose/efeitos dos fármacos , Apoptose/genética , Neoplasias do Tronco Encefálico/genética , Neoplasias do Tronco Encefálico/mortalidade , Neoplasias do Tronco Encefálico/patologia , Linhagem Celular Tumoral , Proliferação de Células , Criança , Glioma Pontino Intrínseco Difuso/genética , Glioma Pontino Intrínseco Difuso/mortalidade , Glioma Pontino Intrínseco Difuso/patologia , Esquema de Medicação , Avaliação Pré-Clínica de Medicamentos , Feminino , Expressão Gênica , Ensaios de Triagem em Larga Escala , Humanos , Camundongos , Camundongos SCID , Mutação , Inibidores de Proteínas Quinases/farmacocinética , Pirazóis/farmacocinética , Piridinas/farmacocinética , Pirimidinas/farmacocinética , Análise de Sobrevida , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Axenfeld-Rieger (AR) ocular anomaly might be due to deletions of different chromosomes. No association between AR, mental retardation, and retinoblastoma has been described. We report a 2-month-old female with general development delay and dysmorphic features. AR anomaly was detected, and a retinoblastoma (RB) was diagnosed in a very early stage. De novo 13q deletion was identified. Systemic chemotherapy, focal cryotherapy, transpupillary thermotherapy, brachytherapy, and intra-arterial chemotherapy were needed to control the RB. This is the first report of an association of AR, 13q deletion, and retinoblastoma, to be disclosed in patients born with such ocular and dysmorphic features.