FOXK2 and osteosarcoma: Conversely, in concordance with our findings, ectopic FOXK2 expression has been shown to induce apoptosis in the osteosarcoma U2OS cells.4 Moreover, FOXK2 has also been shown to recruit BAP-1, an important tumour suppressor, to the chromatin and to promote local deubiquitination during DNA damage response.6