Expression of Class III Beta-tubulin Predicts Prognosis in Patients with Cisplatin-resistant Bladder Cancer Receiving Paclitaxel-based Second-line Chemotherapy

Abstract

Background/Aim: Class III beta-tubulin (TUBB3) expression is recognized as a predictive marker for chemosensitivity to cisplatin- and taxane-based chemotherapies in various malignancies. The aim of this study was to clarify the predictive value of TUBB3 expression for the anticancer effects of first-line cisplatin-based chemotherapy and second-line paclitaxel-based chemotherapy in patients with urothelial cancer (UC). Patients and Methods: We reviewed 116 patients with UC (90 with bladder cancer and 27 with upper urinary tract cancer) treated with first-line cisplatin-based chemotherapy. Among them, 42 patients received a paclitaxel-based regimen as second-line chemotherapy for advanced cisplatin-resistant UC. TUBB3 expression was evaluated using immunohistochemistry, and survival analyses were performed using Kaplan–Meier survival curves and multivariate Cox proportional hazard analysis. Results: TUBB3 was mainly detected in the cytoplasm of cancer cells, and 64 patients (55.2%) were judged as having positive TUBB3 expression. TUBB3 expression was significantly associated with tumour grade (p<0.001). TUBB3 expression was not associated with time to progression after first-line cisplatin-based chemotherapy. However, positive expression of TUBB3 was significantly associated with unfavourable overall survival in patients receiving second-line paclitaxel-based chemotherapy (p=0.021). In addition, a multivariate analysis model