SPHK2 and neoplasm: Opaganib®, also known as ABC294640, is an orally available, competitive and highly selective sphingosine kinase-2 (SK2) inhibitor (Ki = 9 μM).24–26 Opaganib® accumulates in tumours and induces apoptosis.26 This accumulation makes Opaganib® an interesting lead for the development of radio imaging agents.