We already described in a previous study the involvement of Wnt/β-catenin signalling pathway in the tumour suppressor effect driven by PTPRG in CML (Tomasello et al., 2020) and the current data reporting the involvement of SMAD pathway is in line with a complex cellular reprogramming induced by PTPRG expression whose key role in the haematopoietic differentiation program was already described (Sorio et al., 1997). This evidence concerns the gene PTPRG and chronic myelogenous leukemia, BCR-ABL1 positive.