The Prognostic Role of the Class III β-Tubulin in Non-Small Cell Lung Cancer (NSCLC) Patients Receiving the Taxane/Vinorebine-Based Chemotherapy: A Meta-Analysis

BACKGROUND A number of studies have examined the relationship between the expression of the class III β-tubulin (TUBB3) and the treatment responses to the taxane/vinorebine-based chemotherapy in patients with non-small cell lung cancer (NSCLC). However, the results of these studies were inconsistent and inconclusive. Therefore, we conducted an up-to-date meta-analysis to evaluate the prognostic role of TUBB3 in the taxane/vinorebine-based chemotherapy. METHODS A literature search for relevant studies was conducted in PubMed, Embase, and CNKI. The inclusion criteria were the taxane/vinorebine-based chemotherapy in patients with NSCLC and the evaluation of the clinical outcomes in relation to the expression of TUBB3. The clinical outcomes analyzed in this study included the overall response rate (ORR), overall survival (OS), and event-free survival (EFS). Odds ratio (OR) or hazard ratio (HR) with 95% confidence interval (CI) were calculated to assess the risk associated with the TUBB3 expression in the taxane/vinorebine-based chemotherapy. RESULTS A total of 28 studies with 2401 NSCLC patients were qualified for this meta-analysis. We found that the positive or high level of TUBB3 expression was associated with a poorer ORR (OR = 0.24, 95% CI = 0.16-0.36, p<0.001), an unfavorable OS (HR = 1.52, 95% CI = 1.27-1.82, p<0.001), and a worse EFS (HR = 1.47, 95% CI = 1.24-1.74, p<0.001) compared to the negative or low level of TUBB3 expression. The statistically significant associations between TUBB3 and chemotherapy responses were also observed in the stratified subgroup analysis, which included the analysis by ethnic subgroup (Asian and Caucasian), chemotherapy regimen (taxane-based and vinorebine-based), TUBB3 detection method (IHC and PCR), and treatment strategy (surgery plus adjuvant chemotherapy and palliative chemotherapy). CONCLUSIONS The expression level of TUBB3 may be a useful biomarker to predict the clinical outcomes of the taxane/vinorebine-based chemotherapy in patients with NSCLC.