The Correlation Of VEGF Expression And Human Non-small-cell Lung Cancer

[Background]Lung cancer is one of the most common malignant tumor which seriously threaten human life and health in today's world. Lung cancer has become the leading cause of death. Of about 80% patients is non-small-cell lung cancer (NSCLC) of which diagnosed at advanced stage, unresectable about 80%.The treatment of NSCLC include surgery, chemotherapy, radiotherapy and molecular targeted therapy, whatever the treatment requires a effective index of guide and judge for the treatment of NSCLC.TNM staging are widely used as the current indicators to evaluate the treatment and prognosis of NSCLC,which provide some guidance value. However, in clinical work, a part of NSCLC patients who although have been the early diagnosis and treatment appeared in the short term recurrence and metastasis, The biological behavior of tumor characteristics of these patients are no doubt more aggressive side. Therefore, it is obviously not enough only depending on TNM staging of lung cancer.Studies have found that tumor growth, invasion and metastasis are dependent on angiogenesis processes, which are closely related to the prognosis of cancer. The same as ohter solid tumors, turmor angiogenesis provide nutrients to promote tumor growth, tumor invasion and metastasis. Tumor angiogenesis involves a variety of different gene mutations and expression of cytokines and their receptors and is regulated both positive and negative factors. In tumor tissues, as pro-angiogenic factors are dominant. Vascular endothelial growth factor (VEGF) is widely recognized as the most important angiogenic factors, and plays an important role in the promotion of tumor microvessels and Lymhangiogenesis. Therefore, the understanding of lung VEGF expression and angiogenesis may help clarify the mechanism of growth and metastasis of lung cancer. Heparins may inhibit endothelial cell proliferation and inhibit angiogenesis, prevent cell adhesion, proliferation and migration, and blocking the violations of tumor from vessels and tissues.Up to now, there have been few reports on the expression of VEGF and microvessel density (MVD) in NSCLC, as well as their relations with the biological behavior and prognosis of NSCLC. The specific anti-tumor mechanism of heparin has not been entirely clarified. In this study, microvessel density (MVD) and VEGF expression were observed in non-small cell lung cancer (NSCLC) by immunohistochemical staining to explore the relationship of MVD/VEGF expression and NSCLC biological behavior and their effects on the prognosis of NSCLC. In this study, MTT and fluorescence quantitative PCR (real-time PCR) were performed to investigate the role of LMWH on VEGF expression in human NSCLC A549 cells. This study aimed to provide theoretical basis for the clinical application of LMWH in NSCLC. PartⅠExpression of VEGF and the Correlation with Angiogenesis in Non-small-cell Lung CancerObjective:To investigate the expression of vascular endothelial growth factor (VEGF) in NSCLC (non-small cell lung cancer) tissues, and study the correlations between the expression of VEGF, the angiogenesis and clinical path physiological characteristics of NSCLC.Methods:43 specimens of NSCLC were the surgical cases who were diagnosed pathologically from January 1996 to January 1999 in the cardio-chest surgical department of the first affiliated hospital of Bengbu Medical College. Immunohistochemical S-P method was used to detect the expression of VEGF and MVD in the organization, So as to provide theory basis for clinical diagnosis and treatment. All data presented were expressed as mean±SEM and analyzed by SPSS version 13.0 statistical software. Data were analyzed by one-way analysis of variance (ANOVA) and student t test. And the data from categorical variables were analyzed by x2 test.Rusults:1. The VEGF-positive rate was 53.50%(23/43) in NSCLC; The MVDs were 31.98±14.93 in NSCLC.2. The positive expression rate of VEGF was 59.4%(18/33) in squamous cell carcinoma and 50%(5/10) in adenocarcinoma, the MVDs were 35.50±15.28 in adenocarcinoma and 30.91±15.25 in squamous cell carcinoma respectively, There was no significant difference among them (P＞0.05).3. The VEGF-positive rates were 12.50%,66.67%和91.67%, the MVDs were 21.25±7.86,32.87±15.27和45.17±11.49 in stageⅠ,ⅡandⅢof NSCLC, The differences of VEGF expression and the MVDs between stageⅠ,ⅡandⅢwere significant respectively (P＜0.01).4. the positive expression rates of VEGF were 84%(21/25) and11.11%(2/18), the MVDs were 39.56±14.73和21.44±7.44 in the group with lymph node metastasis and the group without lymph node metastasis. Between the two groups, the differences of VEGF expression and the MVDs were significant respectively (P＜0.01).5. The average MVD (42.83±11.915) in VEGF-positive expression group was significantly higher than the average MVD (19.50±5.726) in VEGF-negative expression group (p＜0.01)Conclusions:1. There are high expressions of VEGF in NSCLC; VEGF expression is significantly related to tumor size, TNM clinical stage and lymph node metastasis in NSCLC.2. MVD was closely related to the degree of histology, lymph node metastasis and TNM in NSCLC. MVD was closely related to malignancy and metastasis of NSCLC.3. The positive expression of VEGF and MVDs in NSCLC was significantly positively correlated, VEGF positively regulate angiogenesis in NSCLC, to target VEGF or its receptors will be expected to be a new treatment approach of NSCLC. PartⅡVEGF Expression,Microvessel Density Related to Prognosis of Human Non-small-cell Lung CancerObjective:To investigate the correlations between the expression of VEGF, the angiogenesis and prognosis of human NSCLC, in order to provide theory basis for clinical diagnosis, prognosis and treatment.Methods:43 specimens of NSCLC were the surgical cases who were diagnosed pathologically from January 1996 to January 1999 in the cardio-chest surgical department of the first affiliated hospital of Bengbu Medical College. Immunohistochemical S-P method was used to detect the expression of VEGF and MVD in the organization The survival time were analyzed by Kaplan-meier following Log-rank test. COX model (likelihood ratio test) was used for the multivariate prognostic analysis. A level of p＜0.05 was considered statistically significant.Rusults:1. Kaplan-Meier analysis showed that survival time of NSCLC patients was significantly correlated with TNM clinical stage, histological grade, lymph node metastasis and tumor size. Furthermore, the mean survival time and median survival time of NSCLC in high MVD expression group and VEGF-positive expression group were significantly lower than that in low MVD expression and VEGF-negative expression group.2. COX model was used to analyze the multivariate prognosis of the patients' age, sex, TNM clinical stage, and MVD/VEGF expression. Results showed that MVD was an independent factor affecting NSCLC prognosis. The relative death risk of patients with high MVD expression was 34.247-fold that of patients with low MVD expression (likelihood ratio test, p＜0.01)Conclusions:The expression of VEGF, MVDs and 5-year survival rate of NSCLC is closely related. Detection of VEGF and MVD may serve as a major parameter to judge the angiogenesis, invasion and metastasis of NSCLC and prognosis of NSCLC, MVD was independent prognostic predictors of NSCLC. Part III Effects of Low molecular weight heparin on VEGF Expression of Non-small Cell Lung Cancer A549 Cell LineObjective:To investigate the effects of the expression of VEGF in A549 cells treated by LMWH, to discuss the influence of the potency of invasion and metastasis of lung cancer cells, and to provide the experimental evidence of using LMWH, in the recess of prevention and therapy Non-small Cell Lung Cancer.Materials and Methods:1.The influence of cell proliferation on Non-small Cell Lung Cancer A549 cell line by LMWH. A549 cells were treated singly at the dosages of 0,5,15,50,150,500IU/ml, for 1～2day respectively. Thereafter, the proliferation of A549 cells was assessed by MTT method.,2. The effects of the expression of VEGF on A549 cells treated by LMWH.A549 cells were treated at different concentrations of LMWH. Then VEGF were detected by Western blotting, and levels of VEGF mRNA were analyzed by SYBR-PCR amplification.Results:1.Being treated with LMWH could obviously inhibit the growth of A549 cells, and the secession effects would be enhanced following increasing dosage or extending treated time. When the concentration of LMWH was between 5IU/ml and 150IU/ml, the MTT assay at 24 hours and 48 hours showed a significant inhibitory action of LMWH, which can inhibit the proliferation of A549 in dose-dependent and time-dependent manner in vitro.2. After being treated with different concentrations of LMWH, level of VEGF mRNA was be obviously decreased (vs. control group, P＜0.05). Level of VEGF protein deeply depressed down-regulated. (Vs. control group, P＜0.05)Conclusions:1.To treat A549 cells with LMWH would obtain regression of cells proliferation.2.LMWH could redress the expression of VEGF which could encouraging tumor vessel angiogenesis, thus to treat A549 cells with LMWH might sores the ability of lung cancer cells to invasion and metastasis.