Prognostic potential of a PSA complex in sera of prostate cancer patients with alpha2-macroglobulin deficiency.
We previously reported on a number of cases of metastatic prostate cancer (PCa) in which serum alpha2-macroglobulin (alpha2M) levels were markedly decreased to less than 20 mg/dl (alpha2M deficiency). In order to elucidate the relative proportions of free and a prostate-specific antigen (PSA) complex in PCa patients with alpha2M deficiency, we have assessed serum alpha2M and total PSA levels, and ratios of free PSA to total PSA (F/T ratios) at each stage of PCa. Moreover, the PSA reactivity profile was determined on fractionated serum specimens of PCa patients using high-performance liquid chromatography (HPLC) using a TSKG-3000 SWXL column. Measurement of alpha2M concentration was performed by laser-nephelometry. PSA levels were determined by enzyme immunoassay, free PSA by radioimmunoassay. In those PCa patients with alpha2M deficiency, serum alpha2M and F/T ratios were lower, whereas PSA levels were higher when compared with those PCa patients without alpha2M deficiency (P<0.05). PSA elution profiles on HPLC columns revealed two major peaks. The proportion of PSA-antichymotrypsin (PSA-ACT) increased, whereas the proportion of free PSA decreased in PCa patients with alpha2M deficiency as compared with those PCa patients without alpha2M deficiency. F/T ratios were significantly lower in PCa patients with alpha2M deficiency than in those PCa patients without alpha2M deficiency. PSA-ACT and F/T ratio may be useful for monitoring bone metastasis in PCa.
Kanoh
Yuhsaku
Y
Department of Laboratory Medicine, School of Medicine, Kitasato University, Kanagawa, Japan. kanoh@med.kitasato-u.ac.jp
Ohara
Tadashi
T
Egawa
Shin
S
Baba
Shiro
S
Akahoshi
Tohru
T
D000230:Adenocarcinoma / Q000097:blood / Q000175:diagnosis* / Q000556:secondary; D000368:Aged; D000369:Aged, 80 and over; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000097:blood*; D011470:Prostatic Hyperplasia / Q000097:blood / Q000175:diagnosis; D011471:Prostatic Neoplasms / Q000097:blood / Q000175:diagnosis*; D000511:alpha-Macroglobulins / Q000032:analysis / Q000172:deficiency*
D000511:alpha-Macroglobulins; D017430:Prostate-Specific Antigen