We have shown previously that the choline-based radiotracer, [11C]choline, which correlates with CHKα expression and represents a proliferation-independent phenotype in prostate cancer [37], decreased predictably following androgen deprivation [38], interpreted as a reduction in choline transport/metabolism or loss of cell viability (similar directionality of change) [39]. This evidence concerns the gene CHKA and prostate carcinoma.