Separating chemotherapy-related developmental neurotoxicity from cytotoxicity in monolayer and neurosphere cultures of human fetal brain cells.
Chemotherapy-induced neurotoxicity can reduce the quality of life of patients by affecting their intelligence, senses and mobility. Ten percent of safety-related late-stage clinical failures are due to neurological side effects. Animal models are poor in predicting human neurotoxicity due to interspecies differences and most in vitro assays cannot distinguish neurotoxicity from general cytotoxicity for chemotherapeutics. We developed in vitro assays capable of quantifying the paediatric neurotoxic potential for cytotoxic drugs. Mixed cultures of human fetal brain cells were differentiated in monolayers and as 3D-neurospheres in the presence of non-neurotoxic chemotherapeutics (etoposide, teniposide) or neurotoxicants (methylmercury). The cytotoxic potency towards dividing progenitors versus differentiated neurons and astrocytes was compared using: (1) immunohistochemistry staining and cell counts in monolayers; (2) through quantitative Western blots in neurospheres; and (3) neurosphere migration assays. Etoposide and teniposide, were 5-10 times less toxic to differentiated neurons compared to the mix of all cells in monolayer cultures. In contrast, the neurotoxicant methylmercury did not exhibit selectivity and killed all cells with the same potency. In 3D neurospheres, etoposide and teniposide were 24 to 10 times less active against neurons compared to all cells. These assays can be used prioritise drugs for local drug delivery to brain tumours.
Cancer Biology, Division of Cancer and Stem Cells, School of Medicine, Queen's Medical Centre, University of Nottingham, Nottingham, UK. Electronic address: delyan.ivanov@nottingham.ac.uk.
Delyan P
DP
Ivanov
School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, UK. Electronic address: mbxaa10@nottingham.ac.uk.
Abdal-Jabbar
AJ
Al-Rubai
Cancer Biology, Division of Cancer and Stem Cells, School of Medicine, Queen's Medical Centre, University of Nottingham, Nottingham, UK. Electronic address: anna.grabowska@nottingham.ac.uk.
Anna M
AM
Grabowska
School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, UK. Electronic address: margaret.pratten@nottingham.ac.uk.
Margaret K
MK
Pratten
D000970:Antineoplastic Agents / Q000633:toxicity*; D001253:Astrocytes / Q000187:drug effects* / Q000378:metabolism; D001921:Brain / Q000166:cytology; D002452:Cell Count; D018929:Cell Culture Techniques; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D005047:Etoposide / Q000633:toxicity*; D005333:Fetus; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D006801:Humans; D008767:Methylmercury Compounds / Q000633:toxicity*; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D020258:Neurotoxicity Syndromes; D010078:Oxazines / Q000378:metabolism; D010084:Oxidation-Reduction; D018874:Spheroids, Cellular / Q000187:drug effects / Q000378:metabolism; D013713:Teniposide / Q000633:toxicity*; D014404:Tubulin / Q000378:metabolism; D014966:Xanthenes / Q000378:metabolism
D000970:Antineoplastic Agents; D005904:Glial Fibrillary Acidic Protein; D008767:Methylmercury Compounds; D010078:Oxazines; C498585:TUBB3 protein, human; D014404:Tubulin; D014966:Xanthenes; C005843:resazurin; D005047:Etoposide; D013713:Teniposide
In vitro neurotoxicity assay; Neural stem cell; Neuronal differentiation; Preclinical screening model; Repurposing chemotherapeutics; Topoisomerase drugs