In vitro propagation and characterization of neoplastic stem/progenitor-like cells from human prostate cancer tissue.
BACKGROUND
According to the cancer stem cell hypothesis, tumor growth is sustained by a subpopulation of cancer stem/progenitor-like cells. Self-renewal and high clonogenic potential are characteristics shared by normal stem and neoplastic stem/progenitor-like cells. We investigated whether human prostate cancer specimens contain cells with these properties.


METHODS
Self-renewal and clonogenic potential were assessed by serial passaging of spheres and colony formation, respectively. Gene expression was analyzed by real time PCR. Protein expression was detected by immunocytochemistry. The neoplastic nature of the cells was verified by detection of the TMPRSS2/ERG gene fusion expression.


RESULTS
The epithelial fraction isolated from surgical specimens generated colonies in 68% (19/28) of the patients. Laminin adhesion selected for cells with high clonogenic potential. The epithelial fraction from 85% (42/49) of the patients generated primary prostaspheres. Serial passaging of prostaspheres demonstrated their self-renewal capacity, which is also supported by their expression of the stem cell markers Oct-4, Nanog, Bmi-1, and Jagged-1 mRNA. Cells derived from prostaspheres were more clonogenic than the parental epithelial fraction. The pattern of mRNA expression in prostaspheres resembled that of the basal compartment of the prostate (CK5(+)/CK14(+)/CK19(high)/CK18(-/low)/c-met(+)/AR(-/low)/PSA(-/low)), but also included stem cell markers (CD49b(+)/CD49f(+)/CD44(+)/DeltaNp63(+)/Nestin(+)/CD133(+)). The distribution of marker expression in prostaspheres suggests their heterogeneous cell composition. Prostaspheres expressed significantly higher PSCA mRNA levels than the epithelial fraction.


CONCLUSIONS
Human prostate cancer specimens contain neoplastic cells with self-renewal and clonogenic potential, which can be enriched and perpetuated in prostaspheres. Prostaspheres should prove valuable for the identification of prostate cancer stem/progenitor-like cells.
Guzmán-Ramírez
Natalia
N
Departments of Urology and Clinical Research, University of Bern, Bern, Switzerland.
Völler
Maureen
M
Wetterwald
Antoinette
A
Germann
Markus
M
Cross
Neil A
NA
Rentsch
Cyrill A
CA
Schalken
Jack
J
Thalmann
George N
GN
Cecchini
Marco G
MG
D015703:Antigens, CD / Q000096:biosynthesis / Q000235:genetics; D000951:Antigens, Neoplasm; D002135:Calcium-Binding Proteins / Q000096:biosynthesis / Q000235:genetics; D048708:Cell Growth Processes / Q000502:physiology; D002999:Clone Cells / Q000473:pathology; D058851:GPI-Linked Proteins; D020869:Gene Expression Profiling; D018398:Homeodomain Proteins / Q000096:biosynthesis / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D036341:Intercellular Signaling Peptides and Proteins / Q000096:biosynthesis / Q000235:genetics; D007381:Intermediate Filament Proteins / Q000096:biosynthesis / Q000235:genetics; D000072100:Jagged-1 Protein; D053547:Keratin-14 / Q000096:biosynthesis / Q000235:genetics; D008297:Male; D008562:Membrane Glycoproteins / Q000096:biosynthesis / Q000235:genetics; D008565:Membrane Proteins / Q000096:biosynthesis / Q000235:genetics; D000071317:Nanog Homeobox Protein; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000235:genetics; D014411:Neoplastic Stem Cells / Q000378:metabolism / Q000473:pathology*; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000235:genetics; D064231:Nestin; D050814:Octamer Transcription Factor-3 / Q000096:biosynthesis / Q000235:genetics; D011471:Prostatic Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis / Q000235:genetics; D019859:Proto-Oncogene Proteins c-met / Q000096:biosynthesis / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D012189:Retrospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000072099:Serrate-Jagged Proteins
D015703:Antigens, CD; D000951:Antigens, Neoplasm; C081876:CKAP4 protein, human; D002135:Calcium-Binding Proteins; D058851:GPI-Linked Proteins; D018398:Homeodomain Proteins; D036341:Intercellular Signaling Peptides and Proteins; D007381:Intermediate Filament Proteins; C000606273:JAG1 protein, human; D000072100:Jagged-1 Protein; D053547:Keratin-14; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; C486780:NANOG protein, human; C577484:NES protein, human; D000071317:Nanog Homeobox Protein; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D064231:Nestin; D050814:Octamer Transcription Factor-3; C110843:PSCA protein, human; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D000072099:Serrate-Jagged Proteins; D019859:Proto-Oncogene Proteins c-met