Prominin-1 (CD133) is not restricted to stem cells located in the basal compartment of murine and human prostate.
BACKGROUND
Rodent and human prominin-1 are expressed in numerous adult epithelia and somatic stem cells. A report has shown that human PROMININ-1 carrying the AC133 epitope can be used to identify rare prostate basal stem cells (Richardson et al., J Cell Sci 2004; 117:3539–3545). Here we re-investigated its general expression in male reproductive tract including mouse and human prostate and in prostate cancer samples using various anti-prominin-1 antibodies.


METHODS
The expression was monitored by immunohistochemistry and blotting. Murine tissues were stained with 13A4 monoclonal antibody (mAb) whereas human samples were examined either with the AC133 mAb recognizing the AC133 glycosylation-dependent epitope or 80B258 mAb directed against the PROMININ-1 polypeptide.


RESULTS
Mouse prominin-1 was detected at the apical domain of epithelial cells of ductus deferens, seminal vesicles, ampullary glands, and all prostatic lobes. In human prostate, immunoreactivity for 80B258, but not AC133 was revealed at the apical side of some epithelial (luminal) cells, in addition to the minute population of AC133/80B258-positive cells found in basal compartment. Examination of prostate adenocarcinoma revealed the absence of 80B258 immunoreactivity in the tumor regions. However, it was found to be up-regulated in luminal cells in the vicinity of the cancer areas.


CONCLUSIONS
Mouse prominin-1 is widely expressed in prostate whereas in human only some luminal cells express it, demonstrating nevertheless that its expression is not solely associated with basal stem cells. In pathological samples, our pilot evaluation shows that PROMININ-1 is down-regulated in the cancer tissues and up-regulated in inflammatory regions.
Missol-Kolka
Ewa
E
Max-Planck-Institute of Molecular Cell Biology and Genetics, Dresden, Germany.
Karbanová
Jana
J
Janich
Peggy
P
Haase
Michael
M
Fargeas
Christine A
CA
Huttner
Wieland B
WB
Corbeil
Denis
D
D000071916:AC133 Antigen; D000368:Aged; D000818:Animals; D015703:Antigens, CD / Q000032:analysis* / Q000235:genetics; D018938:Caco-2 Cells; D006023:Glycoproteins / Q000032:analysis* / Q000235:genetics; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008875:Middle Aged; D010455:Peptides / Q000032:analysis* / Q000235:genetics; D011467:Prostate / Q000737:chemistry* / Q000166:cytology; D011471:Prostatic Neoplasms / Q000737:chemistry; D013234:Stem Cells / Q000737:chemistry*
D000071916:AC133 Antigen; D015703:Antigens, CD; D006023:Glycoproteins; C000606023:PROM1 protein, human; D010455:Peptides; C000606024:Prom1 protein, mouse