Abstract
Sphingosine-1-phosphate (S1P), a bioactive sphingolipid, is produced by sphingosine kinase 1 (SK1) and SK2 and acts through paracrine, autocrine and intracellular signaling pathways. Changes in S1P levels, SK1 and SK2 enzymes, as well as S1P receptors, have been described in cancer. Furthermore, S1P have also been recognized as important cellular mediator in hypoxia and angiogenesis. Hypo…