Specific to cancers, TOPK is regulated by protein phosphatase 2A (PP2A) and BCR/ABL in leukemia and enhances cell proliferation, indicating that it may be a target of BCR/ABL [45], and has been associated with HTLV-1-transformed T-cell lines and ATLL-derived T-cell lines [17]. Here, BCR is linked to adult T-cell leukemia/lymphoma.