Purpose To assess the expression of DLL4 in non-small cell lung cancer ( NSCLC) patients and to determine its associa-tion with clinicopathological parameters and prognosis. Methods DLL4 expression was evaluated in NSCLC tissues and adjacent non-cancerous normal lung tissues from 89 patients undergoing surgical treatment by immunohistochemistry. Results DLL4 had high ex-pression in 52 of 89 cases of NSCLC (58. 4%), which was significantly higher than that in adjacent non-cancerous lung tissues (P<0. 05). Moreover, DLL4 overexpression was significantly correlated with TNM stage (P=0. 010 78). Kaplan-Meier survival analysis showed that the overall survival times in patients expressing DLL4 in NSCLC were shorter. Conclusion High level of DLL4 expression is significantly correlated with NSCLC progression and unfavorable prognosis. Thus, DLL4 expression may be used as a clinical param-eter for predictive prognostication of NSCLC patients.

Objective: To explore the high expression level of serum heat shock protein 90α(HSP90α) and gene HSP90 AA1 in cancer tissue, and to discover the prognosis of lung cancer. Methods: A total of 109 cases of lung cancer were collected as the experimental group; 38 lung inflammation groups as the reference group; and 30 healthy controls. The serum HSP90α levels between the three groups were compared; the correlation between HSP90α and clinical parameters were analyzed. The TCGA data were used to analyze the correlation between the expression level of HSP90 AA1 and various pathological features, as well as its influence on the prognosis of lung cancers. Results: The serum HSP90α concentrations in the experimental group were higher than those of the reference group and the control group(P<0.05). The ROC curve area of HSP90α in the diagnosis of lung cancer was 0.898(P<0.05); the expression of HSP90α in the lung squamous cell carcinoma group(LUSC) and the small cell lung cancer group(SCLC) were higher than those in lung adenocarcinoma group(LUAD)(P<0.05); the level of HSP90α decreased when condition alleviated, while increased significantly when disease progressed(P<0.05); Further TCGA database showed that the expression of HSP90 AA1 in cancer tissues was higher than that of adjacent cancer tissues(P<0.05),meanwhile, remarkably increased in LUSC compared with in LUAD(P<0.05). The expression of HSP90 AA1 has no significant correlation with the age, gender, clinical stage, and tumor residue of lung cancer patients. Survival analysis and Cox regression analysis showed that high expression of HSP90 AA1 reduced the overall survival(OS) of lung cancer patients; HSP90 AA1 was an independent prognostic factor for lung cancer patients. Conclusion Serum HSP90α and HSPAA1 in cancer tissues are elevated in patients with lung cancer, which should be used as an auxiliary diagnosis method for lung cancer. Meanwhile they should be used for therapeutic effect observation and survival status prediction.