HER2 and tau expression as potential markers for response and survival to first line taxane plus cisplatin therapy in non-small cell lung cancer

Aim: The aim of this study was to assess the role of various HER2, tau and bcl2 as prognostic markers of responsiveness to taxane and cisplatin therapy in patients with advanced NSCLC. Methods: Amplification of HER2 gene determined by chromogenic in situ hybridization (CISH) and HER2, tau and bcl2 protein expression determined by immunohistochemistry were assessed in 49 patients with NSCLC enrolled in our four clinical trials of taxane plus cisplatin chemotherapy. Results: The patients were classified as responders or non-responders, a negative tau expression was associated with a significantly higher rate of response compared to a positive tau expression (OR 3.33, 95% CI 1.01-10.97, P = 0.043). Patients with more than stable disease compared to those with progressive disease showed that negative amplification of the HER2 gene was associated with a significantly higher rate of disease control compared to positive amplification (OR 7.35, 95% CI 0.83-65.21, P = 0.048). Furthermore, HER2 gene amplification was strongly associated with the overall survival: 20 months (95% CI 9.007-30.993) in patients with negative amplification of the HER2 gene versus 12 months (95% CI 6.584-17.416) in patients with positive amplification of the HER2 gene (P = 0.040). A multivariate analysis with the Cox proportional hazards model confirmed that HER2 gene amplification was a significant independent prognostic factor with a hazard ratio of 2.334 (95% CI 1.060-5.142, P = 0.035). Conclusion: Tau protein expression and HER2 gene amplification are the prognostic factors in NSCLC patients treated with a taxane and cisplatin combination.