Expression And Clinical Significance Of MTH1 In Non-Small Cell Lung Cancer

Objectives To explore the expression of purine nucleoside triphosphatase 1,mutT homolog 1(MTH1)in non-small cell lung cancer(NSCLC)tissues and its underlying meaning.Materials and Methods The pathological tissue samples of 197 patients NSCLC diagnosed in our hospital from March 2011 to March 2013 were collected.Immuno-histochemical method was used to detect the expression of MTH1 protein.The relationship between MTH1 expression and clinical characteristics of patients were analyzed.Kaplan-Meier survival curve method was used to analyze the expression of MTH1 and prognosis of the patients.Cox proportional hazards model was used to analyze the MTH1’s impact on overall survival and disease-free survival of the patients.RESULTS MTH1 was highly expressed in 111 cases(56.3%)and low expressed in86 cases(43.7%).High expression of MTH1 is positive associated with male(p=0.0297),smoking > 100cigarettes(p<0.0001),squamous cell carcinoma(p=0.0064),pathological stage>stage I(p<0.0001),tumor diameter> 3 cm(p=0.0012),lymph node metastasis(p=0.003),pleural infiltration positive(p=0.0063),lymph node infiltration(p=0.0171),and vascular infiltration(p=0.0002)significantly.The 5-year overall survival rates and 5-year disease-free survival rates in patients with high or low MTH1 expression were 81.6% vs 92.3%(p = 0.0011)and 55.0% vs 83.7%,respectively(p =0.0002).MTH1 expression(HR 1.713,95% CI: 1.865-4.118,P=0.047)and lymph node metastasis(HR 9.190,95% CI: 2.824-39.457,P<0.0001)were independent risk factors for overall survival;MTH1 expression(HR 1.605 95% CI(1.627-3.248),P=0.039)and lymph node metastasis(HR 4.502 95%(1.942-11.546),P=0.0003)were independent risk factors for disease-free survival.Conclusions Patients with high MTH1 expression exhibited more malignant characteristics,tend to have shorter disease-free survival and overall survival rates.MTH1 could be a potential prognostic marker for non-small cell lung cancer.