However, a broad division could be made depending on whether the cell line derived from a p53 mutant or null tumour cell like with low-dose radioresistance (a wide shoulder / high α/β ratio) where NTE, at least in the form of bystander effects (BE), were not seen and p53 wild-type, low-dose radiosensitive cell lines (small shoulder, low α/β ratio) where NTE were pronounced [145]. This evidence concerns the gene TP53 and neoplasm.