Identification of adipophilin as a potential diagnostic tumor marker for lung adenocarcinoma

In our previous study, the upregulation of adipophilin in lung adenocarcinoma were identified compared with normal lung tissues by quantitative proteomics. In this study, our aim was to verify the result from quantitative proteomics, further investigate the relationship between adipophilin expression and clinicopathologic factors of lung cancer patients. The expression levels of adipophilin were examined in 10 pairs of lung adenocarcinoma and normal lung tissues using western blotting and the expression and cellular distribution of adipophilin were determined by IHC in 62 formalin-fixed and paraffin embedded primary lung cancer specimens. Adipophilin expression was significantly higher in lung adenocarcinoma specimens than in normal tissues and lung squamous cell carcinomas (P<0.05). There were no significant difference of adipophilin expression between lung squamous cell carcinomas and normal lung tissues. The expression of adipophilin in lung cancer did not correlate with any clinicopathologic factors such as lymph node metastasis, patients' age, gender, tumor size, grade, and TNM stage. In Conclusion, Adipophilin was upregulated in lung adenocarcinoma, suggesting that adipophilin play an important role in tumorigenesis of lung adenocarcinoma and may serve as a potential marker for lung adenocarcinoma.