Background: Prostate-specific antigen (PSA) is a glycoprotein tumor marker known to exist as numerous glycospecies. Investigations on its glycobiochemical properties aimed at their use in the preparation of adjuncts in determining PSA concentration for clinical purposes have accumulated a lot of data on its structural properties. In this study, we reconsidered unexplored ubiquitously present low molecular mass species of PSA regarding to molecular mass, origin and pathophysiological source specificity in order to evaluate them as biomarkers.
Methods: Data on low molecular mass PSA-immunoreactive species from sera of subjects with prostate cancer (PCa), benign prostatic hyperplasia (BPH), breast cancer (BCa), and urine of healthy males obtained by on-chip immunoaffinity chromatography combined with mass spectrometry were analyzed.
Results: The results obtained indicated PSA species common to BCa, PCa, and BPH at 12-13 kDa, 17-19 kDa and 21-24 kDa. The striking difference in predominant frequencies made the profile characteristic in each examined pathophysiological condition. On the other hand, paired groups of prostatic and extraprostatic PSA contained rare species with small differences among groups concerning individual species. Low molecular mass PSA also included rare species unique for each group of samples.
Conclusion: The results obtained revealed that uniformity of low molecular mass PSA-immunoreactive species in sera prevails over diversity related to cancer and non-cancer conditions, but at the same time some of them are molecules with biomarker potential for BPH detection.
Uvod: Specifičan antigen prostate (PSA) je glikoproteinski tumorski marker koji postoji u obliku brojnih molekulskih vrsta. Podaci o njihovim glikobiohemijskim osobinama su dobijeni u studijama vršenim u cilju ispitivanja mogućnosti njihovog korišćenja kao dodatnog kliničkog parametra. U ovom radu je analiziran biomarkerski potencijal PSA vrsta koje imaju malu molekulsku masu a koje, do sada, bez obzira na njihovo univerzalno prisustvo, nisu ispitivane u smislu specifične povezanosti sa različitim patofiziološkim stanjima.
Metode: Analizirani su podaci o PSA-imunoreaktivnim vrstama male molekulske mase u serumima osoba sa kancerom prostate (PCa), benignom hiperplazijom prostate (BPH), kancerom dojke (BCa) i urinima zdravih muških osoba koji su dobijeni imunoafinitetnom hromatografijom na čipu u kombinaciji sa masenom spektrometrijom.
Rezultati: Dobijeni rezultati su ukazali na predominantne PSA vrste male molekulske mase u regionima 12–13 kDa, 17–19 kDa i 21–24 kDa koje su bile zajedničke za sve ispitivane grupe uzorka. U zavisnosti od patofiziološkog stanja, njihova zastupljenost se, međutim, izrazito razlikovala između datih regiona. Pored ovih, detektovane su i retke mole-kulske vrste zajedničke za prostatični i ekstraprostatični PSA, kao i retke vrste karakteristične za svaku od ispitivanih grupa uzoraka.
Zaključak: Uprkos tome {to sličnost PSA vrsta male molekulske mase preovladava nad raznovrsnošću vezanom za maligno ili benigno fiziološko stanje, postoje one koje ima ju biomarkerski potencijal za detekciju BHP.
Keywords: benign prostatic hyperplasia; breast cancer; low molecular mass species; prostate cancer; prostate-specific antigen.