Differential expression of CD44 during human prostate epithelial cell differentiation.
CD44 is a polymorphic transmembrane glycoprotein that binds hyaluronan and growth factors. Multiple isoforms of the protein can be generated by alternative splicing but little is known about the expression and function of these isoforms in normal development and differentiation. We have investigated the expression of CD44 during normal prostate epithelial cell differentiation. A conditionally immortalized prostate epithelial cell line, Pre2.8, was used as a model system. These cells proliferate at 33C but at 39C stop dividing and undergo changes consistent with early stages of cell differentiation. During the differentiation of these cells, the expression of the CD44 isoform v3-v10 was upregulated. Two layers of epithelial cells can clearly be distinguished in the human prostate, a basal layer expressing keratins 5/14 and a luminal layer expressing keratins 8/18. In prostate tissue the v3-v10 isoform was found predominantly in basal cells but also in keratin 14-negative, keratin 19-positive cells intermediate between the two layers. CD44 v3-v10 was also expressed in other keratin 14-negative prostate tissues, the ejaculatory ducts and prostatic urethra. Therefore, CD44 v3-v10 may be important as a cell surface marker for differentiating cells in the prostate epithelium.
Alam
Tahirah N
TN
Prostate Cancer Research Centre, Institute of Urology, University College London, London, UK.
O'Hare
Michael J
MJ
Laczkó
István
I
Freeman
Alex
A
Al-Beidh
Farah
F
Masters
John R
JR
Hudson
David L
DL
D002454:Cell Differentiation; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000166:cytology; D006801:Humans; D018960:Hyaluronan Receptors / Q000096:biosynthesis*; D007150:Immunohistochemistry; D008297:Male; D011467:Prostate / Q000166:cytology / Q000378:metabolism*; D011470:Prostatic Hyperplasia / Q000378:metabolism; D020033:Protein Isoforms; D020133:Reverse Transcriptase Polymerase Chain Reaction
D018960:Hyaluronan Receptors; D020033:Protein Isoforms