The Promoter Hypermethylation Rate Of MGMT In Non-small-cell Lung Cancer And Relationship With K-ras

Background and ObjectiveLung cancer is one of the most popular and the highest mortality rate carcinomanowadays.Canceration is the result of enviromental and inherit factors interaction, involving in many genes and processes. One hand,human expose themselves to the dangerous entiromental factors,which result in the damaging of DNA,and the activation of oncogenes and the inactivation of anti-oncogenes .The other hand,because of existing genetic polymorphism,people with susceptible genotype ,expose to the risk entiromental factor.Alkylating agent is a kind of main chemical carcinogen,its mechanism is form of O~6-methylguain (O~6-MedG) which brings on the mutation of DNA (G:C→A:T). O~6-methylguain DNA methyltransferase(MGMT) may resect and repire O~6-MedG,maintain the genome stability .The inactivation of MGMT gene may urge the proto oncogene activation.The ras gene is one of important proto oncogene .Its familty is made up of K-ras,H-ras,R-ras. K-ras gene has the most intimate relationship with lung cancer,it is recognized the key gene of carcinogen .The method of research is immunohistochemistry and methylation specific PCR.The purpose is to explore the promoter hypermethylation of MGMT gene, the expression of MGMT and K-ras , their relationship in lung cancer, seek the effect of MGMT in non-small cell lung cancer and provide the theoretical basis in genetic diagnosis of lung cancer.Materials and methods60 surically resected non-small-cell lung cancer tissues were collected.The age was from32 to 72,average 45.3.Among them male 32 ,female 28;squamous cancer 38,adenocarcinoma 22.In squamous,well-differentiated 14,moderate 12,poorly-differentiated 12.In adenocarcinoma,well- differentiated 10,moderate 8,poorly-differentiated 4.Among squamous,there were lymph node metastasis in 24 and no lymph node metastasis in 14.Among adenocarcinoma,there were lymph node metastasis in 12 and no lymph node metastasis in...