CXCL8 and posterior cortical atrophy: In a Phase II clinical trial, PCa patients with the highest serum levels of prostatic 1,25(OH)2D also had low COX-2 levels, but exhibited high IL-6 levels in their stroma tissue.63 Interestingly, 1,25 (OH)2D treatment suppressed TNF-α, IL-6, and IL-8 levels in primary epithelial cells, but only TNF-α and COX-2 levels were downregulated in stromal cells.