Expression Of COX-2 And P-gp In Non-small Cell Lung Cancer And Their Relations To HPV Infection

【Objections】1. To study the relationship between COX-2 and P-gp, and to investigate the role of COX-2 in MDR of NSCLC;2. To analyze the expression of COX-2 and P-gp and their association with clinicopathological features in NSCLC;3. The relationship between COX-2 and P-gp expression and HPV infection was also discussed.【Methods】To collect 54 cases of NSCLC tissues and 16 cases of lung benign diseases tissues, the protein expression levels of COX-2 and P-gp were detected by IHC assay in NSCLC group, the levels of HPV16/18 DNA in both groups were respectively examined by PCR .【Results】1. The expression of COX-2 and P-gp and the relationship between them in NSCLCThe positive expression rate of COX-2 and P-gp was 59.3%(32/54)and 46.3%(25/54)respectively in NSCLC, there was no positive expression of COX-2 and P-gp detected in normal controls; The positive expression rate of P-gp was significantly higher in COX-2 positive group 65.6%(21/32) than in COX-2 negative group 18.2%(4/22).The over-expression of COX-2 was significantly correlated with P-gp expression in NSCLC(r=0.468,P<0.05); 2. The expression of COX-2 and P-gp and their association with clinicopathological features in NSCLCThe expression of COX-2 was significantly correlated with the histological type of NSCLC, lung squamous cell carcinomas showered much higher COX-2 positive expression rate than lung adenocarcinomas (P<0.05), however, no correlation was found between COX-2 expression and sex, age, differentiation degree, lymph node metastasis,clinical stage as well as smoking history of the patients in NSCLC; The expression of P-gp is not associated with clinicopathological features in NSCLC;3. The relationship between COX-2 and P-gp expression and HPV infection The detection rate of HPV16/18 DNA was 40.7 % in NSCLC group and 6.25% (1/16) in the benign diseases group, with a significant difference between the two groups (P < 0.05); The expression of COX-2 was not associated with HPV infection(P>0.05 ); The percentage of positive of P-gp was no evident difference between HPV16/18 DNA positive 40.9%(9/22) and negative 50.0%(16/32) (P>0.05).【Conclusions】1. The over-expression of COX-2 was significantly correlated with P-gp ,which strongly suggests that COX-2 might take part in mediation of MDR in NSCLC through up-regulating the expression of P-gp;2. The expression of COX-2 participated the carcinogenesis and development of NSCLC, and had a general significance in lung adenocarcinoma;3. HPV infection was detected in some cases of NSCLC, which suggested that HPV infection might be another important etiological factor in carcinogenesis of NSCLC;4. The expression of COX-2 and P-gp didn't cooperate with HPV infection in the occurrence and development of NSCLC.