COL1A2 and plasma cell myeloma: To assess the role of myeloma-expressed hnRNPA2B1 in osteoclast-mediated bone resorption in vivo, we examined the levels of mouse serum procollagen type I N-terminal propeptide (PINP), a bone formation marker and C-telopeptide of type I collagen (CTX-1), a bone resorption marker.