The Expression Of Tetraspanin CD151in NSCLC And Its Effect On Invasion And Metastasis

1. Background and PurposeLung cancer, as one of the seriously threatening diseases to human health and life, has the highest incidence of disease and death among all the global malignancy tumors. In2008, Chinese incidence of lung cancer reached38.8/105. It is estimated that lung cancer will be still ranked the top of newly increased incidence and death rate in2020in China. According to the third national summary report about death causes, malignancy tumors ranked the second place as its percentage of22.32. Nevertheless it took the first place in urban areas. Lung cancer ranked the top death cause as its percentage of22.7of all the malignancy tumors and it has been main target of prevention for a long time in China. The80%of lung cancer is NSCLC. Although great progress in the early diagnosis and standardized treatment of NSCLS, the surgery treatment opportunity is only5%-15%. Even if surgery treatment is received,50%of patients will re-emerge and5years survival is only8%-10%. The third national report about death causes illustrates Xuanwei County and Gejiu City in Yunnan province are one of the highest incidence areas of lung cancer, especially the incidence and death rate of female lung cancer in this area ranks the top in the world. This high incidence of Xuanwei Cancer has its distinctly regional features. The heterogenicity of tumor is the most important biological feature of malignancy tumors. After about30years’research, Xuanwei Cancer has made progress in pathological research and the incidence has been controlled in small areas by means of environmental improvement to some extent, but total incidence and death rate of lung cancer in this ares are still very high. Therefore it is necessary to explore rules of its occurrence and development in order to pursue effective therapeutic regiment and propose synthetical treatment perscription according to its distinct regional features.CD151is a member of the transmembrane4superfamily. members of this family are involved in the coordination of intracellular and intercellular processes, including signal transduction, cell motivation, development, proliferation and motility. The overexpression of tetraspanin CD151-a transmembrane protein that promotes tumor invasion and metastasis-is associated with poor prognosis in various cancers.We assyed the expression of transpan CD151in NSCLC and its effect on metastasis and invasion in A540and XWLC-05cell lines.2. Methods1. SP immunohistochemical staining was applied to explore the expression of CD151and integrin α3β1protein in specimens of81NSCLC and22benign pulmonary diseases. The correlation between the expression of CD151and integrin α3β1protein and clinicopathologic features was analyzed.2. qRT-PCR was applied to explore the expression of CD151mRNA in BEAS-2B, A549, Xuanwei lung adenocarcinoma cell lines XWLC-05and Gejiu lung squamous carcinoma cell lines YTMLC.3. Recombinant plasmid aimed to interference CD151gene was constructed and transfected into A549as well as XWLC-05.4. The proliferation ability of A549and XWLC-05was tested by MTT.5. The migration ability of A549and XWLC-05was tested by wound-healing assay.6. The invasion ability of A549and XWLC-05was tested by Transwell assay.7. Influence of CD151inhibition by RNAi on lung metastasis in null mice given tail veins injection of A549and XWLC-05.3. Results1. The positive rate of CD151protein in specimens of NSCLC was55.6%(45/81), which was higher than18.2%(4/22) of benign pulmonary diseases (x2=9.70, P=0.002). The positive rate of integrin α3β1protein in specimens of NSCLC was49.4%(40/81),which was higher than22.7%(5/22) of benign pulmonary diseases (x2=4.8025, P=0.025)2. Overexpression of CD151protein in NSCLC was correlated with histology; the expression of CD151in lung adenocacinoma was higher than in squamous cell carcinoma and other (x2=7.068, P=0.029). Overexpression of CD151protein in NSCLC was not correlated with sex, age, smoking status, T-stage, N-stage, cell differentiation and Performance Status. Overexpression of integrin α3β1protein in NSCLC was correlated with histology; the expression of integrin α3β1protein in lung adenocacinoma was higher than in squamous cell carcinoma and other (2=10.070, P=0.007). Overexpression of integrin α3β1protein in NSCLC was not correlated with sex, age, smoking status, T-stage, N-stage, cell differentiation and Performance Status.3. Cox regression suggested CD151protein expression was an independent prognostic factor of NSCLC (P=0.001). High CD151protein expression in NSCLC may be associated with a poor prognosis.4. There was positive correlation between the expression of CD151protein and α3β1protein in NSCLC (r=0.458, P=0.000)5. qRT-PCR showed the expression of CD151mRNA was BEAS-2B> A549> XWLC-05>YTMLC.6. The proliferation ability of A549and XWLC-05were not influenced by RNAi (P>0.05)。7. Inhibition of CD151gene expression can reduce migration and invasion ability of A549and XWLC-05.(P<0.05)8. Inhibition of CD151gene expression can reduce lung metastasis in null mice given tail veins injection of lung adenocarcinoma cell lines A549and Xuanwei lung adenocarcinoma cell lines XWLC-05.4. Conclusions1. The expression of CD151and integrin α3β1protein was higher in specimens of resected NSCLC than that in benign pulmonary diseases. There was positive correlation between the expression of CD151and α3β1. High CD151protein expression in NSCLC may be associated with a poor prognosis. Assessment of both CD151and integrin α3β1protein expression could be instrumental for improvements in lung cancer knowledge involve biological behaviour and prognosis.2. Inhibition of CD151gene expression can reduce migration and invasion ability of A549and XWLC-05A549in vitro.3. Inhibition of CD151gene expression can reduce lung metastasis in null mice given tail veins injection of lung adenocarcinoma cell lines A549and Xuanwei lung adenocarcinoma cell lines XWLC-054. CD151may become one of the potential therapeutic targets aiming for to inhibit invasion and metastasis of NSCLC.