Significance of elevated serum concentration of type Ⅰ collagen metabolites and its correlation with serum interleukin 6 activities in multiple myeloma

摘要

In this study, serum concentrations of carboxyterminal propeptide of type Ⅰ collagen(PICP) and carboxyterminal cross-linked telopeptide of type Ⅰ collagen (ICTP), which represent the rates of synthesis and degradation of type Ⅰ collagen, were determined by radioimmunoassay in 56 patients with multiple myeloma (MM) and 22 healthy controls. It was discovered that serum concentrations of both PICP and ICTP were higher in MM than those in healthy controls (P<0. 01 ). With the disease progressing and the number of bone lesions increasing,serum concentration of ICTP elevated while serum concentration of PICP showed no significant change. Neither serum PICP nor ICTP concentration was related to M-component classes. Our results indicated that serum ICTP concentration was a good serological marker to reflect severity of bone lesions in MM and elevated serum PICP concentration might be due to compensatory increase in type Ⅰ collagen synthesis. Moreover, we also found that serum ICTP concentrations in MM correlated with serum interleukin-6 (IL-6) activities (r= 0. 610, P< 0. 01),which confirms the effectiveness of IL-6 as an osteoclast activating factor.