Are plasma insulin-like growth factor I (IGF-I) and IGF-binding protein 3 (IGFBP-3) useful markers of prostate cancer?
Increased concentrations of insulin-like growth factor I (IGF-I) and decreased insulin-like growth factor binding protein 3 (IGFBP-3) in serum have been proposed as markers of prostate cancer (CaP). The evidence for this, however, is contradictory. We assayed serum for IGF-I, IGFBP-3 and prostate-specific antigen (PSA) in patients with CaP and benign prostatic hyperplasia (BPH) and in healthy controls (HC). The mean +/- SD concentration of IGF-I in CaP (98.3 +/- 39.3 ng/mL; n = 15) was lower than in BPH (119 +/- 31.1 ng/mL; n=24) and HC (119 +/- 36.1 ng/mL; n=46), but the differences between the three groups were not statistically significant (p > 0.05). The mean IGFBP-3 concentrations in CaP (2691 +/- 1105 ng/mL; n = 16; p = 0.029) and BPH (2618 +/- 816 ng/mL; n = 26; p = 0.006) patients were significantly lower than that of the HC (3119 +/- 618 ng/mL; n=59), but the difference between the two groups of patients was not significant (p > 0.05). PSA concentrations in CaP (median = 80.8 ng/mL; n = 25) were significantly higher than those in BPH (median = 8.6 ng/mL; n = 39) (p < 0.001). Ninety-six percent of CaP and 72% of BPH patients had PSA concentrations >4.0 ng/mL; the proportions of patients with concentrations exceeding 20 ng/mL were 76% and 10%, respectively. We conclude that IGF-I and IGFBP-3 are inferior to PSA for CaP detection.
Lopez
J B
JB
Institute for Medical Research, Kuala Lumpur, Malaysia. lopez@imr.gov.my
Sahabudin
R M
RM
Chin
L P
LP
D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D006801:Humans; D006965:Hyperplasia / Q000097:blood; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood*; D007334:Insulin-Like Growth Factor I / Q000096:biosynthesis*; D008297:Male; D008875:Middle Aged; D011467:Prostate / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000175:diagnosis*
D014408:Biomarkers, Tumor; D018972:Insulin-Like Growth Factor Binding Protein 3; D007334:Insulin-Like Growth Factor I; D017430:Prostate-Specific Antigen