| Introduction:Lung cancer is a malignant tumor with the highest morbidity and mortality in the whole world,while China is one of the countries which have a high incidence of lung cancer.Despite some progresses in lung cancer diagnosis and treatment in recent years,the prognosis remains poor.The occurrence and development of tumors is a multi-stage,multi-factor and multi-step process under the control of complex molecular networks.Therefore,exploring the relationship between lung cancer functional genes and their malignant biological characteristics and further understanding the relevant mechanism of action is crucial for designing a reasonable therapeutic drug and improving the clinical prognosis.The Rac3 gene is a new member of the Rac subfamily in the Rho family,which was originally reported by Haataja and others in 1997.The Rac subfamily in Rho family plays an important role in cell migration and other processes.Rac3 of the Rac subfamily is found in a large number in brain tissue,but it is also expressed in many other tissues with few relevant studies.E-cadherin,a member of the EMT family,was first cloned by Berx in 1995.EMT is a process in which an epithelial cell undergo multiple biochemical changes to obtain interstitial phenotype and increase migration capacity.The invasion and metastasis of malignant tumors are related to it.E-cadherin is a kind of calcium-dependent cell adhesion molecule,which is widely existed in normal epithelial cells,and functions to mediate adhesion between epithelial cells to maintain the normal morphology and polarity of the tissues.In addition,it has been reported that the expression of Rac1 in lung cancer was significantly correlated with E-cadherin,N-cadherin,Vimentin,Snail1 and Snail2,This indicates that Rac1 may affect the invasion and metastasis of lung cancer through EMT.There is no relevant research in the same family of Rac3,which provides follow-up researchers with a direction.Based on the above background and technical conditions,we make the assumption that the Rac3 gene may promote the invasion and metastasis of lung cancer cells through the promotion of epithelial mesenchymal transition.We intend to conduct a immunohistochemical detection on lung cancer issue.This study can provide a basis for elucidating that the Rac3 gene is involved in the invasion and metastasis of non-small cell lung cancer,and further the understanding of Rac3 gene in-depth.Objective:To investigate the expression of Rac3 and E-cadherin in non-small cell lung cancer and the relationship between the expression of Rac3 and clinicopathological factors and prognosis.To investigate the effect of Rac3 on the invasion and metastasis of non-small cell lung cancer and its relationship with E-cadherin.Methods:A total of 162 non-small cell lung cancer patients,including 99 males and 63 females,who underwent surgical treatment and had complete follow-up data from January 2009 to December 2010 in our hospital was collected.These patients were aged40-80 years,with a median age of 59 year old.None of them received chemotherapy,radiotherapy or any other adjuvant therapy before the surgery.Detect the expression of Rac3 and E-cadherin in carcinoma and its adjacent tissues of patients with lung adenocarcinoma by immunohistochemical staining method;explore the relevance of Rac3 and E-cadherin and patients prognosis by single and multifactor analysis;compare the effects of Rac3 and E-cadherin positive expression on patients' survival period by Kaplan-Meier method;and compare the correlation of Rac3 and E-cadherin expression in non-small cell lung cancer tissue.Results: Immunohistochemical staining demonstrated that among the 162 non-small cell lung cancer patients,the positive expression of Rac3 in carcinoma tissue was 101 cases(62.3%),which was higher than 15 cases(9.3%)in adjacent non-tumor tissues.The difference was statistically significant(P<0.05).In 91 cases of adenocarcinoma,the positive expression of Rac3 in carcinoma tissues was 58 cases(63.7%),which was higher than 7 cases(7.7%)in adjacent non-tumor tissues.In adenocarcinoma,the expression of Rac3 gene was related to the degree of tumor differentiation,the TNM staging of the tumor,and the survival status of the patient.Single and multifactor analysis showed that Rac3 expression was an independent factor influencing the prognosis of adenocarcinoma patients.Kaplan-Meier survival analysis indicated that the survival period of patients with Rac3 positive expression was significantly shorter(P<0.05).In E-cadherin,57 cases out of 162 patients with non-small cell lung cancer had positive carcinoma cytomembrane expression(35.2%).It was weaker than that 38 cases out of 43 patients had positive expression of adjacent carcinoma bronchial cytomembrane(88.4%)(P<0.05).92 cases carcinoma cytoplasmic positive expression(56.8%)is stronger than 4 cases out of 43 cases expression in adjacent carcinoma bronchial cytoplasm(10.3%)(P<0.05).This indicates that E-cadherin was ectopically expressed in NSCLC,and the positive site shifted from the cell membrane to the cytoplasm.Correlative analysis suggested that the expression of Rac3 was related to the expression of E-cadherin in the cytomembrane(P<0.05).Conclusions:1.Rac3 is positively expressed in NSCLC.E-cadherin is ectopically expressed in NSCLC,and the positive site shifts from the cell membrane to the cytoplasm.2.Rac3 is positively expressed in lung adenocarcinoma,and is related to the patient's TNM staging,the degree of tumor differentiation,and the survival status of the patient.3.The expression of Rac3 and E-cadherin are two independent risk factors of the prognosis for lung adenocarcinoma patients respectively.4.Patients with Rac3 positive expression have significantly shorter survival period than those with negative expression.5.The expression of Rac3 in lung adenocarcinoma is negatively correlated with the expression of E-cadherin in cytomembrane. |
PDF Full Text Request