Expression And Clinical Significance Of Amyloid Precursor Protein In Non-small-cell Lung Carcinoma

Objective: To detect the level of APP(amyloid precursor protein,APP)and statistically analyze its correlation with clinicopathologic features in tumor and adjacent tissues,so as to explore its role in the tumorigenesis and development,and uncover its clinical significance in non-small cell lung cancer.Methods: 47 pairs of tumor and adjacent tissues,confirmed by histology,from patients who have performed operation in the department of thoracic in Zunyi Medical College,are collected.The protein levels of APP are examined by immunohistochemistry and western blot,and the m RNA levels are checked by q RT-PCR in tumor and adjacent tissues.The correlation of APP expression with clinicopathologic characteristics,such as age,gender,smoking history,tumor size,lymph node metastasis,TNM stage and pathological type,are statistically analyzed and the clinical significance is also investigated.Results: By immunohistochemistry,APP is mainly expressed in the cytoplasm of non-small cell lung cancer cells,and its expression is significantly higher in tumor tissue comparing with its adjacent tissue(P<0.05).Further analysis indicates that APP protein expression is significantly higher in lymph node metastasis tumor tissue comparing with non-lymph node metastasis tumor tissue,and its expression in stage III tumor tissue is higher than that in stage I-II(P<0.05);However,there are no significant correlations between APP expression with age,gender,smoking history,tumor size and pathological type(P>0.05).The results of western blotting show that the expression of APP protein in tumor tissue is significantly higher than that in adjacent tissue.QRT-PCR results shows that the expression levels of APP m RNA decrease in tumor tissues,and the average bold is0.51,compared with adjacent tissues.Conclusion:1.APP is positively expressed in the cytoplasm of NSCLC cells;2.The expressions of APP in NSCLC tumor tissue is significantly higher than that in adjacent tissue.3.The level of APP in NSCLC is significantly correlated with lymphatic metastasis and TNM stage,but is not significantly associated with age,sex,smoking,tumor size and pathologic type.