Yu et al. Journal of Experimental & Clinical Cancer Research 2010, 29:119 http://www.jeccr.com/content/29/1/119 R E S E A R C H Open Access Expression of transcription factors snail, slug, and twist in human bladder carcinoma Qinchao Yu1, Kejun Zhang2†, Xinsheng Wang1*†, Xiangping Liu3, Zemi Zhang2 Abstract Background: Slug, Snail, and Twist are transcription factors that regulate the expression of tumor suppressors such as E-cadherin. In this study, we aimed to examine the expression of these transcription factors in human bladder carcinoma. Methods: We first investigated expression of Slug, Snail, Twist and E-cadherin in five bladder Carcinoma cell lines by reverse transcription-polymerase chain reaction and western blotting. Furthermore, we investigated Slug, Snail, and Twist and E-cadherin expression by immunohistochemistry with bladder carcinoma (tumor, n = 120; background, n = 42). Results: Expression of Slug mRNA and protein was detected in all cell lines, Twist was clearly expressed in two out of five bladder carcinoma cell lines, Snail was not expressed, and E-cadherin was detected in 3 cell lines. 44.2% (53/120) of human bladder Carcinoma tissues and 38%(16/42) background tissue showed an expression of Twist; 62.5%(75/120) of human bladder Carcinoma tissues and 40%(17/42) background tissue showed an expression of Slug, 15.8% (19/120) of human bladder Carcinoma tissues and 76%(32/42) background tissue showed an expression of Snail, and 25.8% (31/120) cases were negative for E-cadherin expression in carcinoma tissues. Expression of Slug and Twist shows increased levels in tumors, whereas Snail seems reduced. Statistically significant correlations were found between Twist, Slug, and E-cadherin expression. Immunohistochemistry analysis showed that Twist was elevated with increasing tumor stage (P = 0.001), the grade (P < 0.001), the progression (P = 0.035). Slug was elevated and Snail was reduced with increasing nodal involvement (tumor-node-metastasis status) (P = 0.004, P = 0.01). E-cadherin was reduced in expression corresponding with tumor grade (P < 0.01). Positive Twist, Slug and E- cadherin expression clearly predicted poorer PFS (P = 0.042, P = 0.014, P = 0.001). In the multivariate analysis, only Snail and E-cadherin expression were independent prognostic factors for OS (P = 0.002, P < 0.001). Conclusions: These data demonstrate that Twist, Snail and Slug have inappropriate expression in bladder carcinoma and that this may play a part in the progression of human bladder carcinoma. Background Bladder cancer is the second most common genitourin- ary tract cancer and the fourth or fifth most common cancer of men in western industrialized countries[1]. In China, bladder cancer is the most common malignancy in genitourinary tract and the fifth most common cancer in men. Generally, radical cystectomy is considered the standard treatment for patients with muscle-invasive tumors, and systemic chemotherapy is the only current * Correspondence: zlfzyj2009@163.com † Contributed equally 1Department of Urology surgery, the Affiliated Hospital of medical college, QingDao University, QingDao, Shan Dong Province, 266403, China Full list of author information is available at the end of the article modality that provides the potential for long-term survi- val in patients with metastatic disease, but the prognosis of patients with advanced bladder cancer is still extre- mely poor despite recent therapeutic advances[2]. It is well known that bladder tumors with the same stage and grade have a heterogeneous clinicaloutcome as they are probably molecularly different. The term of superfi- cial or invasive bladder tumor is confusing as it implies that only one kind of superficial or invasive bladder can- cer exists[3]. Understanding the molecular biology of bladder cancer and metastasis may provide insight for the development of novel tumor markers or new thera- peutic strategies. © 2010 Yu et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.