When cultured in a “promineralization medium” that contains ascorbic acid (known to promote skeletal-like ECM formation in osteoblasts) and a source of phosphate (for hydroxyapatite formation), C4-2B cells produce and retain approximately 8x more mineralized calcium than parental LNCaP cells. C4-2B cells also express higher levels of osteoprotegerin (OPG), alkaline phosphatase, bone sialoprotein (BSP), Osteocalcin (OCN), RANKL, and Osteonectin (OSN) mRNA, all of which are highly expressed by osteoblasts.
