The Expression And Clinical Significance Of Galectin-3 In Non-small Cell Lung Cancer

Backgroud:Lung cancer is the world's fastest-growing malignant tumor over the past two decades.According to investigations in developed countries and major cities in China,lung cancer accounts for the first of the insistence and mortality of men with malignancy.As to women,the mortality caused by lung cancer is also the highest,and the incidence is in the second.The rising tendency is going on up to now. As we know,non-small cell lung cancer accounts for more than eighty percent of lung cancer.Galectin-3,which is characterized by high affinity for beta-galactosides,is a beta-galactoside-binding protein.It is also a member of Galectins family.The relative molecular mass of Galectin-3 is 31-KDa,and it consists of repeated sequences rich in proline and glycine, an amino-terminal and a COOH-terminal connective to carbohydrate. Galectin-3 has been shown to play an important role in cell-cell and cell-matrix interactions and in mRNA splicing process.Moreover,it is closely related to the growth,adhesion and apoptosis of the cells, inflammatory reaction,immunological regulation,neoplastic transformation and metastasis.Galectin-3 is expressed the most in the activated macrophage,basophils,epithelial cells and sensory neurons.It exists in the cytoplasm mainly,also can be found in the cell nucleus,the cell surface or outside the cell.Recently many investigators proved that the over-expression of galectin-3 is positively related to the progression of malignant tumors originated in the gastrointestinal system,the central nervous system and thyroid.Purposes:This research detects various tissues and serum expression of Galectin-3 in patients with non-small cell lung cancer or benign tumor and the health.The probable dependability between Galectin-3 and non-small cell lung cancer may provide new rationale for the diagnosis and therapy of lung cancer.Methods:1 Using SP immunochemistry to detect the expression level of Galectin-3 in the 106 tissue samples,which includes 46 samples of non-small cell lung cancer tissues,46 samples of adjacent tissue and 20 samples of lung benign tumor tissue.2 Using enzyme linked immunosorbent assay(ELISA) to detect the serum concentration of Galectin-3 in the patients with non-small cell lung cancer or lung benign tumor and the health.Results:1.31 samples of non-small cell lung cancer express positive Galectin-3,with a total positive rate of 72.09%(31/43).There are 12 cases of squamous carcinoma(12/21,57.14%),and 19 cases of adenocarcinoma(19/22,86.36%).The positive expression rate of Galectin-3 in the adjacent tissues is 30.23%(13/43),and 35%for lung benign tumor tissues(7/20).The expression of Galectin-3 in the non-small cell lung cancer is higher than adjacent tissues and lung benign tumors with a significant difference statistically(P＜0.01);there is no significant difference of Galectin-3 expression between adjacent tissues and lung benign tumors(P＞0.05).In the non-small cell lung cancer group,the positive expression of Galectin-3 in adenocarcinoma is higher than in squamous carcinoma(P=0.000).Concerning the metastatic carcinoma in lymphonode,it is significantly higher than non-metastasis(84%/55.56%.) The expression of Galectin-3 in the non-small cell lung cancer tissues was significantly correlated with TNM stage of tumor(P=0.015) and lymph node metastasis(P=0.015);but not statistically related with the age(P=0.859),sex(P=0.469),and smoking(P=0.196).2.The serum level of Galectin-3 in the non-small cell lung cancer group(2.01±0.67 ng/ml)is obviously higher than the lung benign tumor group(1.43±0.48 ng/ml) and the health group(1.13±0.55ng/ml),there is statistical significance.In the non-small cell lung cancer grou,pthe serum level of Galectin-3 in adenocarcinoma(2.19±0.51 ng/ml) is higher than in squamous carcinoma(2.02±0.76ng/ml),but it is not statistical significance(P＞0.05).In non small cell lung cancer group:Ⅲ-Ⅳstage patients:2.21±0.49ng/mlⅠ-Ⅱstage patients:1.98±0.38 ng/ml,Ⅲ-Ⅳstage patients higher thanⅠ-Ⅱstage patients.the group of lymphnode metastasis:2.51±0.42 ng/ml,the group of non lymphnode metastasis: 1.73±0.55 ng/ml,the group of lymphnode metastasis was higher than the group of non lymphnode metastasis.(P＜0.01).The group of the intermediate and high differentiattion carcinoma:1.91±0.57 ng/ml,the group of the poorly differentiattion carcinoma:2.03±0.36 ng/ml,there is no prominent difference between the intermediate high differentiattion's group and the poorly differentiattion's group.Conclusions:1.Galectin-3 shows a high expression in the non-small cell lung cancer tissues.High Galectin-3 expression was significantly associated with the type,the degree of tumor differentiation.,TNM staging and lymphatic metastasis,but not related with the age,sex,and smoking.2.Galectin-3 shows a high expression in the serum of patients with non-small cell lung cancer.It is related to TNM staging and lymphatic metastasis,and has nothing to do with the type and differentiation level of the tumor.3.The differential expression of Galectin-3 points to the genesis, progress and metastasis of lung cancer.