Analysis of membrane-bound complement regulatory proteins in prostate cancer.
OBJECTIVE
Membrane-bound complement regulatory proteins (mCRPs) are ubiquitously expressed throughout the cells of the hematopoietic system and protect host cells from complement-mediated lysis. The expression and functionality of mCRPs have been demonstrated in several types of cancers; however, no clear correlation has been appreciated between tumor stage and mCRP expression.


METHODS
We investigated the expression pattern of CD46, CD55, CD59, and CD97 (a receptor for CD55) in prostate cancer by tissue microarray analysis using high-density tissue microarrays spotted with tissue cores from biopsy and autopsy specimens. Real-time polymerase chain reaction was used to confirm the tissue microarray data by quantifying mRNA expression in clinically identified tissue specimens.


RESULTS
CD55 and CD97 demonstrated increased expression in prostatic intraepithelial neoplasia, localized prostate cancer, and metastatic prostate cancer specimens compared with normal tissue specimens. No appreciable difference was seen in CD46 or CD59 expression. These data were confirmed by real-time polymerase chain reaction of mRNA expression levels in grossly identified specimens.


CONCLUSIONS
These data suggest that mCRPs are differentially expressed in prostate cancer, with CD55 the predominant mCRP upregulated in malignant prostate epithelial cells. Additionally, CD97 expression correlated with the malignant phenotype and may contribute to the tumorigenic and metastatic potential of prostate cancer.
Loberg
Robert D
RD
Department of Urology, Michigan Urology Center, University of Michigan Health System, Ann Arbor, Michigan 48109-0946, USA. rloberg@umich.edu
Wojno
Kirk J
KJ
Day
LaShon L
LL
Pienta
Kenneth J
KJ
D015703:Antigens, CD / Q000032:analysis / Q000096:biosynthesis*; D018958:CD55 Antigens / Q000032:analysis / Q000096:biosynthesis*; D018957:CD59 Antigens / Q000032:analysis / Q000096:biosynthesis*; D006801:Humans; D008297:Male; D051916:Membrane Cofactor Protein / Q000032:analysis / Q000096:biosynthesis*; D008562:Membrane Glycoproteins / Q000032:analysis / Q000096:biosynthesis*; D011471:Prostatic Neoplasms / Q000737:chemistry / Q000276:immunology*; D043562:Receptors, G-Protein-Coupled
C095004:ADGRE5 protein, human; D015703:Antigens, CD; D018958:CD55 Antigens; D018957:CD59 Antigens; D051916:Membrane Cofactor Protein; D008562:Membrane Glycoproteins; D043562:Receptors, G-Protein-Coupled