Associations of IgG N-linked oligosaccharide chains and proteases in sera of prostate cancer patients with and without α2-macroglobulin deficiency

✍ Scribed by Yuhsaku Kanoh; Shin Egawa; Shiro Baba; Tohru Akahoshi

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 114 KB
• Volume: 23
• Category: Article
• ISSN: 0887-8013
• DOI: 10.1002/jcla.20302

✦ Synopsis

Abstract

We previously reported on a number of cases of metastatic prostate cancer (PCa) in which serum α2‐macroglobulin (α2M) levels were markedly decreased to less than 20 mg/dl (α2M deficiency). All PCa patients with α2M deficiency had multiple bone metastases. Proteases in ten PCa patients with and without α2M deficiency were studied and compared against ten healthy controls in order to elucidate the relationships between changes in sugar chain structure and neoplasia. We assessed the relationship between ratios of Fr4 to Fr1 and Fr2 (Fr4/Fr1+Fr2 ratios) of oligosaccharide chains, and ratios of free prostate‐specific antigen (PSA) to total PSA (F/T ratios), and serum levels of matrix‐metalloproteinase‐2 (MMP‐2) in PCa progression. Measurement of serum α2M concentration was performed by laser nephelometry. Serum PSA and MMP‐2 levels were determined by enzyme immunoassay and free PSA by radioimmunoassay. N‐linked oligosaccharides of human serum immunoglobulin G were analyzed using fluorophore‐associated carbohydrate electrophoresis. In those PCa patients with α2M deficiency: (a) serum α2M and F/T ratios were lower (P<0.05) and (b) Fr4/Fr1+Fr2 ratios and serum MMP‐2 levels were higher when compared with those PCa patients without α2M deficiency. There was a significant correlation between Fr4/Fr1+Fr2 ratios and F/T ratios or serum MMP‐2 levels in PCa with α2M deficiency (P<0.05). Therefore, these markers may serve as an auxiliary serum tumor marker for monitoring of the bone metastases or progression of disease in PCa. J. Clin. Lab. Anal. 23:125–131, 2009. © 2009 Wiley‐Liss, Inc.