Article

Association of steroid and xenobiotic receptor (SXR) and multidrug resistance 1 (MDR1) gene expression with survival among patients with invasive bladder carcinoma

Department of Urology, Clínica Universitaria Universidad de Navarra, Pamplona, Spain.
BJU International (Impact Factor: 3.13). 06/2011; 107(11):1833-8. DOI: 10.1111/j.1464-410X.2010.09653.x
Source: PubMed

ABSTRACT OBJECTIVE To investigate the prognostic value of steroid and xenobiotic receptor (SXR) and multidrug resistance 1 (MDR1) gene expression in relation to survival among patients with invasive bladder cancer. PATIENTS AND METHODS The prospective study included 67 patients diagnosed with invasive bladder cancer and treated with radical cystectomy at one of two institutions. SXR and MDR1 gene expression was assessed by real-time quantitative polymerase chain reaction (RT-PCR) in tumoral and normal tissue from frozen surgical specimens. RESULTS Patients were followed for a mean of 29 months; 31 patients (46%) had progression. In univariate analysis, significant predictors of overall survival (OS) were pathological stage, lymph node (LN) status, histological grade, vascular-lymphatic invasion, and SXR expression. In multivariate analysis, independent predictors of OS were LN status (odds ratio [OR], 2.96; P = 0.034), vascular-lymphatic invasion (OR, 2.50; P = 0.029), and SXR expression (OR, 1.05, P = 0.03). Among the 51 patients with negative LNs (pNO), univariate predictors of OS were SXR expression, MDR1 expression, and pathological stage. In multivariate analysis, SXR expression (OR, 1.06; P = 0.01) and MDR1 expression (OR, 3.27; P = 0.03) were independently associated with survival. Within the pNO group, patients with SXR expression had shorter progression-free survival than did those without expression (P = 0.004). This association persisted in the NO subgroup with stage pT3-pT4 disease (P = 0.028). However, in the pN1 group SXR expression did not have any influence. CONCLUSIONS For patients with invasive bladder cancer, SXR expression has value as a predictor of survival independent of the standard pathological predictors. Its maximum importance appears to be in patients with stage pT3-pT4 pNO disease.

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