Overexpression of AIB1 negatively affects survival of surgically resected non-small-cell lung cancer patients

Abstract

BackgroundThe amplified in breast cancer 1 (AIB1) gene has been considered to play an oncogenic role in human cancers, but its clinical/prognostic significance in non-small-cell lung cancer (NSCLC) is still unclear. Patients and methodsThe methods of immunohistochemistry and FISH were utilized to examine protein expression and amplification of AIB1 in 230 informative surgically resected NSCLCs and in 30 samples of normal lung tissues. ResultsOverexpression and amplification of AIB1 were found in 48.3% and 8.2% of NSCLCs, respectively. AIB1 overexpression was associated with AIB1 gene amplification and cell proliferation but not related to estrogen receptor (ER)-α, ER-β, progesterone receptor or androgen receptor status. A positive correlation between AIB1 overexpression and an ascending pathologic node stage in lung adenocarcinoma (ADC) was observed (P = 0.043). Univariate survival analysis demonstrated a significant association of AIB1 overexpression with shortened patient survival, especially for those with stage III disease (P < 0.001). Importantly, AIB1 expression was evaluated as the most significant predictor for survival in multivariate analysis (hazards ratio = 2.069, P < 0.001). ConclusionOverexpression of AIB1 might provide a selective advantage for lymph node metastasis of lung ADC and serve as a useful biomarker for poor prognosis for NSCLC patients.