In particular, the SphK1 isozyme, with its isoforms SphK1-a and SphK1-b, is over-expressed in numerous types of cancer cells, leading to an increase in S1P levels and a concomitant reduction in Cer levels, thus suppressing the pro-apoptotic signals and simultaneously creating a survival signal [18,19]. This evidence concerns the gene SPHK1 and cancer.