This comparative (normal donor versus prostate cancer) study showed that: 1) the level of 15-LO-1 expression (the key enzyme in the LA pathway) is low (P < 0.001), whereas the levels of delta-5 desaturase (P < 0.001, the key enzyme in the AA pathway), delta-6 desaturase (P = 0.001), elongase (P = 0.16) and 15-lipoxygenase-2 (15-LO-2, P = 0.74) are higher in donor (normal) prostates, and 2) However in PCa tissues, significantly high levels of only 15-LO-1; whereas low levels of delta-6 desaturase, elongase, delta-5 desaturase and 15-LO-2 respectively, were observed. This evidence concerns the gene FADS2 and prostate cancer.