Abstract: ObjectiveTo investigate the expressions of coxsackie and adenovirus receptor (CAR) and group B adenovirus receptor (CD46) in human non-small cell lung cancer (NSCLC) and its clinical significance. MethodsThe expressions of CAR and CD46 were detected by immunohistochemical technique in 144 cases of NSCLC and the relationships were analyzed between the expressions of CAR or CD46 and the transfection efficiency of adenovirus or development of NSCLC. ResultsIn 144 samples from NSCLC patients, the expression rates of CAR in squmaous cell carcinoma and adenocarcinoma were 77.5%(31/40) and 36.8%(14/38) and CD46 were 58.3%(14/24) and 88.1%(37/42). There were significant differences between CAR and CD46 expression in the squmaous cell carcinoma and adenocarcinoma (P＜0.05). Meanwhile, CAR positive rate was 43.3%(13/30) in TNM stageⅠpatients and 66.7%(32/48) in stage Ⅱ～Ⅲ patients,(P＜0.05). The results showed that CAR expression was closely related to the clinical TNM staging in NSCLC. ConclusionThe expression levels and pattern of CAR and CD46 were significantly different in various pathological types of NSCLC. Positive expression of CAR usually in squamous cell carcinoma, while CD46 is in adenocarcinoma,indicated that different receptor-dependent adenovirus might have transfection efficiency in various pathologic types of NSCLC. Expression of CAR protein is also correlated to the malignant degree of NSCLC.CAR might play an important roles in evalution of prognosis of NSCLC.