Expression Of LKB1 In Chinese Gastric Cancer And Its Clinical Significance

Objective: Gastric cancer is one of the most common malignant tumors in China, and it is a kind of disease which is harm to human health seriously. The generation and development of gastric cancer are more than a multi-gene and multi-stage changing process, in which the activation of cancer gene mutation and inactivation of tumor suppressor gene play an important role in the development of gastric cancer. Compare to advanced gastric cancer, early gastric cancer have a better prognosis. Therefore, it is more important that searching for cancer gene markers of development of gastric cancer, studying the relationship between the formation of gastric cancer activation of oncogene and inactivation of tumor suppressor gene, establishing the simple and feasible indicators in the diagnosis and prognosis of gastric cancer, which are particularly important. LKB1 gene mutation is the main pathogenic factor in the development of Peutz-Jeghers syndrome (PJS), and it plays an important role in the occurrence and development of many kinds of sporadic tumors. Currently, the expression of the LKB1 protein in gastric cancer tissue is not clear, the impact of its expression on the occurrence and development of gastric cancer, incuding the prognosis of it, have not yet been known. This experiment is to study the relationship between expression of LKB1 in Chinese gastric carcinoma and its pathologic features and survival time, in order to provide a new target for the clinical diagnosis and prognosis. Meanwhile, it can provide a new target for the treatment of gastric cancer.Methods: This work selected 100 cases of gastric cancer and normal gastric mucosa, 31 cases of pathological diagnosis of lymph node metastasis of gastric cancer randomly in the Second Affiliated Hospital of Dalian Medical University, testing the expression levels of LKB1 protein in the organization by immunohistochemistry of peroxidase labeled streptavidin egg sensitized (SP), in which normal breast tissue as a positive control, each group consisting of positive and negative controls are located, the positive result is the coloring on the nucleus or cytoplasm, and made the aggregated analysis combining the results with the clinical pathological factor such as age, gender, tumor size, depth of invasion, differentiation, lymph node metastasis and distant metastasis and so forth. At the same, this work carried out the further study of the relationship between the expression of LKB1 protein and the survival time of patients.Results: LKB1 protein was expressed in normal gastric epithelial tissue, gastric cancer and the metastatic cancer in lymphoid tissue. The positive reaction signal is mainly in the cytoplasm, and nucleus also expressed. Its positive rate was 86.00% (86/100), 32.00 % (32/100) and 10.60% (7 / 66) respectively, the positive rate of them have a significant difference. There was no significant difference between the expression of LKB1 protein and patient gender, age, tumor size, location, degree of differentiation and the depth of invasion (P> 0.05). However there was significant difference in lymph node metastasis, distant metastasis and TNM stage (P <0.05). The prognosis of the negative group of LKB1 protein is poor, the median survival time was only 21 months, but the positive group was 34 months, the difference is statistically significant (P <0.05).Conclusion: LKB1 gene was related to the occurrence and development of gastric cancer. There is correlation between the down-regulation of the expression of LKB1 gene and occurrence of lymph node and distance metastasis in patients with gastric cancer. Determination of gastric cancer in the expression level of LKB1 protein will conduct to decision the prognosis.