Predictive value of microtubule associated proteins tau and stathmin in patients with nonmuscle invasive bladder cancer receiving adjuvant intravesical taxane therapy.

PURPOSE: After encouraging results from 2 clinical trials performed at our institution to test intravesical taxane based chemotherapy for bacillus Calmette-Guérin refractory, nonmuscle invasive bladder cancer we designed a study to identify molecular markers linked to the optimal response to such treatment modality.

MATERIALS AND

METHODS

Included in the institutional review board approved study were 32 patients with nonmuscle invasive, bacillus Calmette-Guérin refractory bladder cancer who received intravesical taxane chemotherapy, that is docetaxel or nanoparticle albumin-bound paclitaxel. Immunophenotype analysis on tissue samples obtained before intravesical taxane therapy was done using a panel of molecular markers, including Ki-67, p53, and the microtubule associated proteins tau and stathmin.

RESULTS

Increased total tau (cytoplasmic and nuclear) and stathmin expression before intravesical taxane therapy was significantly associated with decreased recurrence-free survival (p <0.0001 and 0.007, respectively). A tau positive phenotype was an independent prognostic factor for recurrence-free survival on multivariate analysis (HR 15.66, 95% CI 2.68-91.71, p = 0.002). Neither the proliferation index assessed by Ki-67 expression nor p53 status was significantly associated with recurrence-free survival.

CONCLUSIONS

Assessment of tau and stathmin protein expression should be considered to select patients before intravesical taxane based chemotherapy for nonmuscle invasive, bacillus Calmette-Guérin refractory bladder cancer since those who have tumors with low tau/stathmin protein expression show a better response to therapy.