In line with our recent data suggesting an autocrine effect of S1P in regulating HIF-1α in hypoxic prostate cancer cells,24 the silencing of Spns2 was associated with a significant inhibitory effect on HIF-2α accumulation under hypoxia in both CAKI-1 and A498 cells (Figure 6b). This evidence concerns the gene SPNS2 and prostate carcinoma.