Immunohistochemical expression of tumor antigens MAGE-A1, MAGE-A3/4, and NY-ESO-1 in cancerous and benign prostatic tissue.
OBJECTIVE
To investigate immunohistochemical expression of MAGE-A and NY-ESO-1/LAGE-1, cancer testis antigens in prostate tissues showing evidence of malignant transformation or benign hyperplasia.


METHODS
112 prostate samples from patients undergoing surgery at the Urology Clinic at the Zagreb Clinical Hospital Center from 1995 to 2003 were investigated in this study. Of these, 92 carcinoma samples were obtained by radical prostatectomy, and 20 benign prostatic hyperplasia samples by transvesical prostatectomy. Three monoclonal antibodies were used for immunohistochemical staining: 77B for MAGE-A1, 57B for multi-MAGE-A and D8.38 for NY-ESO-1 expression.


RESULTS
Expression of MAGE-A1 was observed in 10.8% of carcinoma samples, whereas multi-MAGE-A and NY-ESO-1/LAGE-1 stained 85.9% and 84.8% of samples. Immunohistochemical staining was only detectable in the cytoplasm. A significant heterogeneity could be observed within a same tissue sample where areas with strong positivities coexisted with cancer testis antigens negative areas. Interestingly, a majority of 57B positive cases were also found to be D8.38 positive (correlation coefficient r=0.727 (P<0.01)). Cancer testis antigens expression was neither significantly correlated with PSA values nor with Gleason score. In benign prostatic hyperplasia tissues MAGE-A1 expression was detected in 5%, while 57B and D8.38 staining was observed in 15% samples, and in all cases percentages of positive cells were always <10%.


CONCLUSIONS
Our data underline the peculiar relevance of cancer testis antigens expression in prostate cancers, with potential implications regarding both diagnosis and therapy.
Hudolin
Tvrtko
T
Department of Urology, Zagreb University Hospital Center, Zagreb, Croatia. thudolin@hotmail.com
Juretic
Antonio
A
Spagnoli
Giulio Cesare
GC
Pasini
Josip
J
Bandic
Daniela
D
Heberer
Michael
M
Kosicek
Miljenko
M
Cacic
Mirjana
M
D000951:Antigens, Neoplasm / Q000378:metabolism*; D045744:Cell Line, Tumor; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D058950:Melanoma-Specific Antigens; D008565:Membrane Proteins / Q000378:metabolism*; D009363:Neoplasm Proteins / Q000378:metabolism*; D011467:Prostate / Q000166:cytology / Q000502:physiology*; D011470:Prostatic Hyperplasia / Q000378:metabolism* / Q000473:pathology; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000473:pathology
D000951:Antigens, Neoplasm; C104948:CTAG1B protein, human; C072013:MAGEA3 protein, human; C095204:MAGEA4 protein, human; D058950:Melanoma-Specific Antigens; D008565:Membrane Proteins; D009363:Neoplasm Proteins