Expression of CK19 mRNA and LUNX mRNA detected by nested PCR for diagnosis of lymph node micrometastasis in non small cell lung cancer

Objective:To investigate the genetic diagnosis for lymph nodes micrometastasis in patients with non small cell lung cancer(NSCLC)and analyze the feasibility of using cytokeratin 19(CK19)mRNA and LUNX(lung-specific X protein)mRNA as mo- lecular marker for detection of micrometastasis in NSCLC.Methods:Using nested PCR,we detected the expression of CK19 mRNA and LUNX mRNA in 149 lymph nodes from 39 patients with NSCLC and 47 lymph nodes from 20 patients with pulmonary benign disea- ses.Results:Among the 149 lymph nodes from 39 lung cancer patients,positive CK19 mRNA expression was detected in 46 lymph nodes(30.9%)and positive LUNX mRNA expression was detected in 56 lymph nodes(37.6%)by nested PCR.Micrometastasis was detected in 20 lymph nodes(13.4%)by histopathological examination.The detection rate was significantly lower than that of nested RT-PCR (P0.01).Neither CK19 mRNA nor LUNX mRNA expression was observed in all the 47 lymph nodes from the patients with pulmonary benign diseases.The CK19 and LUNX mRNA expression was significantly different between the patients with NSCLC and pulmonary benign diseases(P0.01).The micrometastasis in lymph nodes were closely related with the pathological classification, cell differentiation,and TNM staging(P0.05).Conclusion:The results suggest that the detection of both CK19 mRNA and LUNX mRNA could be used as molecular marker for detection of micrometastasis in NSCLC.Combined detection might be helpful for early di- agnosis of lung metastasis to guide the personalized therapy in clinic.