Abstract: Objective To explore the expressions of CD133 and CD82/KAI1 in bladder urothelial carcinoma, their association
with the clinicopathological factors and their roles in vasculogenic mimicry (VM) in the tumor. Methods The expressions of
CD133 and CD82/KAI1 and VM were detected by immunohistochemistry and histochemistry in 90 specimens of bladder
urothelial carcinoma and 20 specimens of normal bladder epithelium tissue. Results The positivity rates of CD133, CD82/KAI1
and VM in normal bladder epithelium tissue were 0, 90% and 0, showing significant differences from the rates of 65.6%, 31.1%
and 31.1% in urothelial carcinoma, respectively (P<0.01). Positive expressions of CD133, CD82/KAI1 and VM were significantly
correlated with pTNM stage and tumor relapse (P<0.01) but not with gender, age, or tumor numbers (P>0.05). CD133
expression was positively correlated with VM (P=0.487, P<0.05), and CD82/KAI1 expression was negatively correlated with
VM (r=-0.452, P<0.01) and CD133 (r=-0.776, P<0.05). Conclusion The expressions of CD133 and CD82/KAI1 proteins are
involved in the occurrence of VM in bladder urothelial carcinoma to contribute to the invasion and relapse of bladder
carcinoma.