Relationship between the expression of MGMT,K-ras in human nonsmall-cell lung cancer and their significance

Objective To investigate the role of O6-methylguanine DNA methyltransferase(MGMT),K-ras in the occurrence,development of non-small-cell lung cancer(NSCLC).Methods SABC immunhistochemical method was performed to detect expression of MGMT,K-ras in 60 surgically resected,paraffin examined non-small-cell lung tissues and tissues adjacent to the tumors.Results 60 surgically resected non-small-cell lung carcinoma tissues were collected.The positive rate of MGMT in lung cancers(33%),was significantly lower(P0.05)than that of MGMT in tissues adjacent to the tumors(63%).The positive rate of K-ras in lung cancers(63%),was significantly higher(P0.05)than that of MGMT in tissues adjacent to the tumors(30%).There was significant difference between positive MGMT expression and tumor differation,lymph node metastasis and smoking(P0.05).No significant difference(P0.05) between positive MGMT expression and age,gender,histology,P-TNM staging,tumor dimension.There was significant difference between positive Kras expression and histology,lymph node metastasis,tumor dimension,smoking(P0.05).No significant difference between positive K-ras expression and age,gender,P-TNM staging(P0.05).Conclusion Negative correlation was observed beween the expression of MGMT and that of K-ras protein in NSCLC(P0.05).The low expression of MGMT may lead to the activation of carcinoma gene K-ras,participate in lung carcinoma and development.The expression of K-ras in adenocarcinoma is higher,that shows K-ras may be the key gene in adenocarcinoma.It may benefit for diagnosis in lung cancer to investigate the two kind of protein.