Abstract: Abstract:Objective To explore the expression of tumor stem cells marker aldehyde dehydrogenase 1(ALDH1) in noninvasive bladder cancer tissue and to investigate the relationship between tumor stem cells and the biological characters of bladder cancer.Methods The expressions of ALDH1 in 118 cases of noninvasive carcinoma specimens and 30 cases of normal bladder tissue surrounding cancer weredetected by immunohistochemistry and analyzed by combining with clinical pathology and prognosis data.Results The positive expression rates of ALDH1 were 24.58% and 6.67% in specimens of cancer and normal bladder specimens,respectively,and the difference between them was statistically significant(P<0.05).The positive expression rate of ALDH1 in high-grade group(36.59%,15/41) was higher than that in low-grade group(18.18%,14/77)(P<0.05).The positive expression rate of ALDH1 in pT1 stage(33.96%,18/53) was higher than that in pTa stage(16.92%,11/65)(P<0.05).The positive expression rate of ALDH1 in recurrent group(37.50%,12/32) was higher than that in primary tumor group(19.77%,17/86)(P<0.05).The ALDH1 expressionwas not related to gender,age and tumor size of patients with noninvasive bladder cancer(P>0.05).During a 4-52 months follow-up period,the tumor-free survival rates in ALDH1-positive group and ALDH1-negative group were 55.17% and 61.80%,respectively.Kaplan-Meier analysis and  Log-rank test showed that the differences of cumulative tumor-free survival rate was statistically significant between ALDH1-positive group and  ALDH1-negative group(P<0.05).Conclusion The ALDH1 expressionis related to the pathological grades,stages and recurrence of bladder cancer.Thetumor stem cells may play a role in the tumorigenesis and recurrence of noninvasive bladder cancer.

Key words: aldehyde dehydrogenase 1, tumor stem cells, noninvasive bladder cancer, immunohistochemistry