Objective To investigate the expression of PTEN and EMMPRIN and their relationships with clinicopathological factors and EGFR mutation in lung adenocarcinoma tissues.

Methods The expression of PTEN and EMMPRIN proteins were examined in 90 cases of lung adenocarcinoma tissues by immunohistochemical method, and 10 cases of normal lung tissues were taken as control. The mutation of EGFR was detected using PCR.

Results PTEN expression in lung adenocarcinoma tissues was significantly lower than that in non-neoplastic internal controls tissues. EMMPRIN expression in lung adenocarcinoma tissues was significantly higher than that in internal controls tissues. The positive rates of PTEN and EMMPRIN expression were 40%(36/90) and 80%(72/90), respectively. EGFR gene mutation rate was 47.78%(43/90). The expression of PTEN was positively correlated with the histological subtypes (P=0.000). EMMPRIN expression was positively correlated with lymph node metastasis status and TNM stage (both P=0.000). Spearman correlation analysis showed that PTEN expression was negatively correlated with EMMPRIN expression (r_p=-0.215, P=0.041). PTEN expression had a positive correlation with EGFR mutation (r_p=0.490, P=0.000). EMMPRIN expression had no correlation with EGFR mutation (r_p=0.170, P=0.110).

Conclusion PTEN and EMMPRIN may have a synergistic effect on the progression and development of lung adenocarcinoma. PTEN expression has a positive correlation with EGFR mutation which may provide evidences for targeted therapy.