36 Quantification of bone resorption by serum PINP Serum samples were collected from all patients and stored at ?40 ��C until analysis. The concentration of PINP fragments was measured by the newly developed selleck chem competitive ELISA assay for human N-terminal propetide of collagen type I (Nordic Bioscience, Herlev, Denmark). The assay was run using 20 ��l undiluted serum samples in a one-step ELISA 1 hour at 4 ��C using a horse radish labeled monoclonal antibody against a 10 amino acid sequence in the N-terminal pro-peptide of collagen type I.30 Mean intra-variation on 10 independent runs was 4.4% on double determinations. Mean inter-variation on 10 independent runs was 5.4% on double determination. Dilution recovery was 90%�C114% on 10 normal serum samples representing the entire range of the standard curve.

30 Bone resorption and number of osteoclasts Data on the collagen type I bone resoption markers �¦�CTX-I32 (assessing resorption of aged collagen type I) and ����CTX-I31 (resorption of newly synthesized collagen type I) and the marker for the number of osteoclasts (TRACP5b) have been published previously by our group15 and these data were used for correlations to the bone formation marker, PINP, detected in serum. The correlation between the CTX-I/TRACP5b ratio, and PINP, was used to indicate resorption activity per osteoclasts versus bone formation. Statistical analysis The values of each of the biochemical markers were logarithmically transformed to obtain normality. Comparisons between the level of PINP in patients with different cancer types without BM was performed by analysis of variance (ANOVA) using the General Linear Models Procedure (GLM).

The same statistical procedure was used for comparison of PINP levels in patients without and with BM for each cancer type. In the comparison of the PINP levels for each Soloway score against the level in patients without metastasis, the Dunnett��s adjustment of Entinostat the level of significance was employed to correct for multiple comparisons. Correlations between the biochemical markers were determined using Spearmans Rho. Differences and associations were considered statistically significant if P < 0.05. GRAPH PAD PRISM 5 (Graph Pad Software, La Jolla, CA, USA) was used for calculations. Results PINP related to bone cancer type Demographics of 161 cancer patients stratified according to cancer type and the presence or absence of BM have previously been reported.15 There were no statistically significant differences in age and BMI between patients with or without BM. Figure 1 shows the mean values of serum PINP in patients stratified according to cancer type and presence or absence of BM.