CDK inhibitors reduce cell proliferation and reverse hypoxia-induced metastasis of neuroblastoma tumours in a chick embryo model

Abstract

Neuroblastoma is a paediatric cancer with a poor prognosis. This is in part due to the widespread metastasis at time of presentation, which is refractory to current treatment modalities. New therapeutic agents that can control not only tumour growth but also metastasis are urgently needed.\n\nOne current therapeutic option used in the clinic is differentiation therapy with retinoic acid, where the terminal differentiation of the neuroblastoma cells reduces tumour growth in the primary tumour as well as at metastatic sites. However, retinoic acid only works in a subset of patients.\n\nWe investigated the potential of CDK inhibitors on neuroblastoma cell differentiation, tumour progression and metastasis by utilising a 3R compliant cost effective preclinical chick embryo model. In both SK-N-AS and BE(2)C cell lines, when engrafted on the chorioallantoic membrane of chick embryos, we observed a reduction of tumour cell proliferation as well as a reduction in hypoxia preconditioning-driven metastasis by 60%. In addition, the expression of a panel of genes with known roles in metastasis, which increased upon hypoxia-preconditioning, was largely reduced by a CDK1 inhibitor. These results provide a promising alternative to currently existing therapies and might aid the development of new treatment protocols for retinoic acid-resistant patients.