The Expression Of KLF5 And KLF6 In Esophageal Cancer

ObjectivesThe aim of this preject is to study the expression of KLF5 and KLF6 in esophageal cancer tissues and normal esophageal tissues, and investigate the relationship between the expression of the KLF5 and KLF6 genes during the esophageal cancer occurrence and development; discuss the relationship of the protein expression of K.LF5 and KLF6 genes and the clinical characteristic of patients, and make the foundation for the further study the mechanism of the KLF5 and KLF6 genes in esophageal cancer.Materials and methods1 Patients tissue source:90 cases of patients which used in immunohistochemical staining were from Pathology Department of the Second Affiliated Hosptital of Zhengzhou University. The paraffin-embedded sections were surgically resected from patients from February 2011 to July 2011, and of which 30 cases were esophageal cancer tissues,30 cases were corresponding normal esophageal tissues, and 30 case were lymph nodes. The criterria of sample selected: (1) The specimens by pathological examination were normal esophageal tissues, esophageal squamous cell carcinoma tissues, and lymph nodes. (2) All patients had not received radiotherapy and chemotherapy. (3) There were with complete clinical and pathological data, including gender, age, depth of invasion, lymph node metastasis, tumor size and clinical stage.42 fresh specimens which were used in RT-PCR were from gastroscope and surgical resection, and of which 21 cases were normal esophageal tissues,21 cases were esophageal cancer tissues.2 Immunohistochemical staining and RT-PCR were used to detect the expression of KLF5 and KLF6 proteins in normal esophageal tissues and esophageal cancer tissues.3 Statistical analyses was performed using the software package SPSS version 10.0. The correlation between the expression levels of KLF5 and KLF6 proteins with different clinicopathological parameteters was measured by a Chi-square test with a Fisher extract test. The McNemar test was used for the correlation between KLF5 expression and KLF6 expression, The Pearson correlation was performed to examine the correlation between the expression of KLF6 and KLF5. The quantitative data was analysed by the paired samples t test. P value<0.05 was considered as significant.Results1 The KLF5 was located in cytoplasm and necleus, with yellow or brown. Of 30 cases with normal esophageal tissues,16 cases expressed KLF5 protein (positive rate 53.3%), of which 6 cases only expressed the protein in the nucleus, eight only expressed in the cytoplasm, two cases expressed in both the cytoplasm and the nucleus. In 30 cases of esophageal squamous cell carcinoma,23 cases expressed KLF5 protein (positive rate 76.7%), of which 12 cases expressed the protein in the nucleus, two cases in the cytoplasm, nine cases in both the cytoplasm and the nucleus. We further analyzed the positive expression of the nucleus KLF5 protein in the normal esophageal tissue and cancer tissues, and found that the nucleus KLF5 protein expression in esophageal cancer tissues was significantly higher than normal tissues, and the difference was statistically significant (P=0.001).2 The KLF6 was located in cytoplasm and necleus, with yellow or brown. Of 30 cases with normal esophageal tissue,8 cases expressed KLF6 protein (positive rate 26.7%), of which 5 cases only expressed the protein in the nucleus,1 only expressed in the cytoplasm,2 cases expressed in both the cytoplasm and the nucleus. In 30 cases of esophageal squamous cell carcinoma,16 cases expressed KLF6 protein (positive rate 53.3%), of which 3 cases expressed the protein in the nucleus,12 cases in the cytoplasm,1 cases in both the cytoplasm and the nucleus. We analyzed the positive expression of the KLF6 protein in the normal esophageal tissue and cancer tissues, and found that the KLF6 protein expression in esophageal cancer tissues was significantly higher than normal tissues, and the difference was statistically significant (P=0.035).3 There was no clear correlation between the positive expression of the KLF5 protein in esophageal carcinoma tissues and patient’s gender, age, depth of tumor invasion, lymph node metastases, tumor size,clinical stage.4 There was no correlation between the positive expression of the KLF6 protein in esophageal carcinoma tissues and patient’s gender, age, depth of tumor invasion, lymph node metastases, tumor size,clinical stage.5 There was no correlation between the protein expressions of KLF5 and KLF6 in normal esophageal tissues; there was no correlation between the protein expressions of KLF5 and KLF6 in normal esophageal tissue cytoplasm and nucleus.6 The expression of KLF5 protein and that of KLF6 protein in esophageal carcinoma tissues was not correlated to each other (P=0.092). The expression of KLF5 protein and that of KLF6 protein in nucleus in esophageal carcinoma tissues had significant negtive correlation (P= 0.000), the correlation coefficient was r=-0.174, but did not have the relevance in esophagus cancer cytoplasm (P=0.754).7 KLF5 and KLF6 protein were expressed in lymph node metastasis tissues, but not expressed in lymph node without metastasis tissues.8 The results of RT-PCR showed that the level of KLF5 and KLF6mRNA in esophageal cancer tissues was higher than that in esophageal normal tissues.Conclusions1 The expression of KLF5 and KLF6 genes are associated with the esophageal cancer, and the abnormal expression of the KLF5 and KLF6 may promote the occurrence of cancer. But the mechanism is still unclear, and need further study.2 The expression of KLF5 and that of KLF6 in esophageal carcinoma cell nucleus has a significant negative correlation, KLF5 and KLF6 proteins in the nucleus may have antagonistic effects, but the mechanisms are unknown, needing further study.