However, there is controversy over the role of CDKN3 in different tumours; some studies suggest that CDKN3 is a tumour suppressor gene [5], since CDKN3 inhibits cell proliferation in glioblastoma [30], chronic myeloid leukaemia [31], and neuroblastoma [32]. This evidence concerns the gene CDKN3 and chronic myelogenous leukemia, BCR-ABL1 positive.