【Abstract】 Objective: To sort the CD133 /CD44 stem cell through MACS from human prostate cancer cell line PC-3 and lay the foundation for the further functional research. Methods: We detected the expressions of CD133 and CD44 on the membrane of PC-3 cell before and after MACS through Flow Cytometry (FCM); then observed the formation of spheres cultured by serum-free medium (SFM) and make subsequent immunofluorescence (IF) assay; distinguished the differences of the morphology、proliferation capacity of PC-3 cell between before and after MACS; detected the expression of prostatic acid phosphatase (PAP) before and after the differentiation assay through immunohistochemical (IHC) and Western blot. Results: The positive expressions of the CD133 and CD44 of the PC-3 cell were (1.33?0.05)% and (0.87?0.06)% through FCM

while they were (84.82?0.07)% and (99.91?0.03)% respectively after MACS; the positive expressions of CD133 and CD44 remained after SFM cultured by immunofluorescence (IF); the proliferation capacity of CD133 /CD44 cell was higher than PC-3 cell (t=11

P=0.008) and CD133 /CD44 cell after induced (t=40.1

P=0.001); the expression of the PAP of the CD133 /CD44 cell after induced by TGF-β was positive

while it was negative in the uninduced CD133 /CD44 cell by IHC and Western blot. Conclusions: The CD133 /CD44 cell had some characteristics of stem cell after MACS from PC-3 cell line through initial functional identification

which could be matting for further explore of the prostate cancer stem cell.