Serum amyloid A, phospholipase A₂-IIA and C-reactive protein as inflammatory biomarkers for prostate diseases.
BACKGROUND
Serum amyloid A (SAA), secreted group IIA phospholipase A₂ (sPLA₂-IIA), and C-reactive protein (CRP) are acute-phase proteins whose serum concentrations increase not only during inflammatory disorders, but also in the course of malignant diseases.


METHODS
In this study we analyzed serum levels of these inflammatory markers along with prostate-specific antigens (PSA) in patients with benign prostatic hyperplasia (BPH, n = 55), localized prostate cancers (PCa, n = 55), and metastatic prostate cancers (mPCa, n = 27) using immunological assays.


RESULTS
We found that in comparison to healthy individuals (n = 55), patients with BPH, PCa and mPCa have elevated serum levels of SAA, sPLA₂-IIA, and CRP, in addition to elevated levels of PSA. Significant differences with respect to inflammatory biomarkers were found between localized and metastatic PCa (p < 0.001), suggesting a prognostic value of these parameters. In addition, serum concentrations of SAA and sPLA₂-IIA positively correlate with CRP in BPH patients (p < 0.05) and in patients with PCa and mPCa (p < 0.001), but not with PSA levels, Gleason score, or tumor stage, emphasizing a role of SAA and sPLA₂-IIA as circulating biomarkers of inflammation rather than of neoplastic transformation. In contrast to PSA, which differed significantly between BPH and localized PCa patients (p < 0.01), such a difference was not found for SAA, sPLA₂-IIA, and CRP. In order to elucidate whether the elevated levels of SAA and sPLA₂-IIA can be caused by cancer cell-associated synthesis, in vitro studies were performed. These analyses demonstrated the expression of SAA and sPLA₂-IIA in LNCaP and PC-3 prostate cell lines, which can be further upregulated by pro-inflammatory cytokines in a cell type-dependent manner. This might suggest that, in addition to the hepatic origin, SAA and sPLA₂-IIA can also be synthesized and secreted by prostatic cancer tissue itself.


CONCLUSIONS
The results of the present study emphasize the utility of SAA, sPLA₂-IIA, and CRP as circulating biomarkers of inflammation during BPH development and PCa progression.
Medical Faculty "Carl Gustav Carus", Institute of Clinical Chemistry and Laboratory Medicine, Technical University of Dresden, Fetscherstrasse 74, 01307, Dresden, Germany, Mario.Menschikowski@uniklinikum-dresden.de.
Mario
M
Menschikowski
Albert
A
Hagelgans
Susanne
S
Fuessel
Olga A
OA
Mareninova
Liana
L
Asatryan
Manfred P
MP
Wirth
Gabriele
G
Siegert
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000032:analysis*; D045744:Cell Line, Tumor; D054501:Group II Phospholipases A2 / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood; D011470:Prostatic Hyperplasia / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood*; D000685:Serum Amyloid A Protein / Q000032:analysis*; D055815:Young Adult
D015415:Biomarkers; D000685:Serum Amyloid A Protein; D002097:C-Reactive Protein; D054501:Group II Phospholipases A2; C516287:PLA2G2A protein, human; D017430:Prostate-Specific Antigen