PBK and Burkitt lymphoma: PBK was identified as an upregulated serine–threonine kinase in Burkitt's lymphoma cell lines.26, 27, 28 PBK was further shown to be upregulated in rapidly proliferating cells as well as a variety of tumor.29, 30, 31 PBK was shown to promote transformation,28 and knockdown of PBK reduced tumorigenic and metastatic properties both in vivo and in vitro.