Hodgkinson et al. [141] were able to graft small cell lung cancer CTCs following subcutaneous injection into the flanks of NSG mice, and then confirmed that these tumours were derived from the isolated CTCs through comparison of genomic profiles for TP53 and RB1. Yu et al. [142] isolated CTCs from breast cancer patients and were able to establish cells lines using non-adherent in vitro culture, where it was noted that greater success of cell line formation occurred using CTCs from patients who were therapy-resistant. Here, TP53 is linked to breast cancer.