CD90/THY1 is overexpressed in prostate cancer-associated fibroblasts and could serve as a cancer biomarker.
A by-product in the processing of prostate tissue for cell sorting by collagenase digestion is the media supernatant that remains after the cells are harvested. These supernatants contain proteins made by the cells within the tissue. Quantitative proteomic analysis of N-glycosylated proteins detected an increased amount of CD90/THY1 in cancer supernatants compared with non-cancer supernatants. Immunohistochemistry showed that in all carcinomas, regardless of Gleason grade, a layer of CD90-positive stromal fibroblastic cells, ∼5 to 10 cells deep, was localized to tumor glands. In contrast, a no more than 1-cell wide girth of CD90-positive stromal cells was found around benign glands. The increased number of CD90-positive stromal cells in cancer correlated with overexpression of CD90 mRNA detected by gene expression analysis of stromal cells obtained by laser-capture microdissection. There is increasing evidence that cancer-associated stroma has a function in both tumor progression and carcinogenesis. Most experiments to identify cancer biomarkers have focused on the cancer cells. CD90, being a marker for prostate cancer-associated stroma, might be a potential biomarker for this cancer. A non-invasive test could be provided by a urine test. Proteomic analysis of urine from patients with prostate cancer identified CD90; conversely, CD90 was not detected in the urine of post-prostatectomy patients. Furthermore, this urinary CD90 protein was a variant CD90 protein not known to be expressed by such cells as lymphocytes that express CD90. These CD90 results were obtained from ∼90 cases consisting of proteomic analysis of tissue and urine, immunohistochemistry, western blot analysis of tissue media, flow cytometry of cells from digested tissue, and reverse transcriptase polymerase chain reaction analysis of isolated stromal cells.
True
Lawrence D
LD
Department of Pathology, University of Washington, Seattle, WA 98195-6100, USA. ltrue@uw.edu
Zhang
Hui
H
Ye
Mingliang
M
Huang
Chung-Ying
CY
Nelson
Peter S
PS
von Haller
Priska D
PD
Tjoelker
Larry W
LW
Kim
Jong-Seo
JS
Qian
Wei-Jun
WJ
Smith
Richard D
RD
Ellis
William J
WJ
Liebeskind
Emily S
ES
Liu
Alvin Y
AY
D000595:Amino Acid Sequence; D001483:Base Sequence; D014408:Biomarkers, Tumor / Q000032:analysis*; D015153:Blotting, Western; D002469:Cell Separation; D005347:Fibroblasts / Q000378:metabolism*; D005434:Flow Cytometry; D006801:Humans; D007150:Immunohistochemistry; D007834:Lasers; D008297:Male; D042282:Microdissection; D008969:Molecular Sequence Data; D011471:Prostatic Neoplasms / Q000235:genetics / Q000378:metabolism*; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism / Q000652:urine; D040901:Proteomics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018800:Thy-1 Antigens / Q000096:biosynthesis* / Q000235:genetics / Q000652:urine
D014408:Biomarkers, Tumor; D020033:Protein Isoforms; D018800:Thy-1 Antigens