Abstract: Objective To examine expression levels of autophagy gene pULK and PI3KC3 and to explore their correlation with non-small cell lung cancer (NSCLC). Methods A total of 77 samples of surgical resection from NSCLC specimens (including 31 cases of squamous cell carcinoma, 31 cases of adenocarcinoma and 15 cases of large cell undifferentiated carcinoma) and 21 samples of same normal lung tissue were randomly selected. Expressions of pULK and PI3KC3 in lung tissues were assessed by immunohistochemistry and Western blot. All dates were analyzed using SPSS13.0 statistical package. Results Immunohistochemistry indicated that pULK and PI3KC3 localized into the cytoplasm. The expression levels of pULK and PI3KC3 are significantly lower in patient with NSCLC than those in peri-tumor tissue (35.1% vs 81.0%, 40.3% vs 76.2% respectively, P＜0.01) . Immunohistochemistry and Western bolt analysis confirmed that pULK and PI3KC3 expressions were significantly down-regulated (P＜0.01) in patients with low grade cellular differentiation,metastasis of lymph node, or stage Ⅲ and Ⅳ. And expression levels of pULK and PI3KC3 in NSCLC did not differ significantly with ages, gender, tumor size and pathological type. Correlation analysis showed that the expression of PI3KC3 was positively correlated with pULK. Conclusion pULK and PI3KC3 expressions were lower in NSCLC than those in normal lung tissue group. The expression levels of pULK and PI3KC3 in NSCLC were correlated with patient's clinical stage, differentiation grade, lymph node metastasis but were unrelated with age, gender, histological type and size.

Key words: autophagy, phosphotransferases (alcohol group acceptor), carcinoma, non-small-cell lung, autophagy related protein 1, phosphoinositide-3-kinase class 3