CDX2 and Familial prostate cancer: VDR Cdx2 AA genotype was associated with prostate cancer in men with low 25(OH)D (≤15 ng/mL) (p interaction = 0.02) and with aggressive and high-grade prostate cancer in men with low 25(OH)D and 1,25(OH)2D (p interaction = 0.04 and 0.01, respectively) compared with men with normal levels [24].