We explored the effects of this on SK function using primary AML cells and leukemia cell lines transfected with SKIP. We demonstrate that SK function and S1P levels were lower in primary AML cells than controls and that SKIP re-expression was associated with an increase in SK activity, and an increase in sphingolipids (mainly S1P and ceramides). The gene discussed is SPHKAP; the disease is acute myeloid leukemia.