PI3K expression predicts overall survival in lung adenocarcinoma

Phosphoinositide 3-kinase (PI3K)/phosphorylated PI3K (p-PI3K) is considered a hallmark in tumor initiation and progression, but its prognostic value in non-small cell lung cancer (NSCLC) remains controversial.

In the present study, we included 118 NSCLC tissue samples and 13 adjacent normal lung tissue specimens. Immunohistochemical staining was applied to test PI3K/p-PI3K expression. Pearson Chi-squared test and Kaplan-Meier curve were conducted to analyze its correlation with both clinicopathological features and prognosis in NSCLC patients.

PI3K/p-PI3K expression in lung cancer tissue differed significantly from that of normal lung tissue (P < 0.001). M stage was significantly correlated to PI3K expression (P = 0.037), but no significant association was found between p-PI3K expression and clinical characteristics. Neither PI3K nor p-PI3K were correlated to overall survival of NSCLC patients (P = 0.105 and P = 0.190, respectively). However, it was found in subgroup analysis that lung adenocarcinoma patients with positive PI3K expression had a favorable survival (P = 0.043). Notably, this correlation was determined invalid in subsequent multivariate analysis (P = 0.052).

PI3K could predict the overall survival of lung adenocarcinoma patients, but failed to be an independent prognostic predictor.