CIAPIN1 Expression In Human Lung Cancer Tissues And Inhibitory Effects Of The Gene On Human Pulmonary Carcinoma Cells

Aim To explore CIAPIN1 gene expression in lung carcinoma tissues and its regulatory effects in the growth of lung cancer cells.Methods Fifty-one formalin-fixed paraffin-embedded specimens of primary lung cancer and their non-cancerous counterparts were detected by SABC immunohistochemistry method. The expression of CIAPIN1 in lung cancer cells and immortalized tracheal epithelial cell was measured by Western blot. After Adenoviral vector construction was recombined and the gene was transduced into NCI-H446/A549 cells, The expression of CIAPIN1 protein was identified by Western blot.MTT assay was used to count the alive cells and to draw a cellular growth curve.The changes of cell cycle and apoptosis were analyzed by flow cytometry. Inhibition effects on tumor growth in vivo were investigated in a nude mouse model. The cell cycle-related molecules of CIAPIN1 inducing cell cycle arrest were detected by Western blot.Results:The positive rate of CIAPIN1 expression in cancer tissues (39.2%)was much lower than that in non-cancerous counterparts(100%)(P<0.05).CIAPIN1 expression was found both in four lung cancer cells and the immortalized tracheal epithelial cell but decreased in NCI-H446/A549 at protein level. In Ad-CIAPIN1 group, the growth of transfected NCI-H446/A549 cells in vitro was significantly inhibited. In addition the Ad-CIAPIN1-induced cell apoptosis and a predominant arrest in the G1/S phase (P<0.01) were observed. The CIAPIN1 mediated by adenovirus can exert the anti-tumor effect on NCI-H446/A549 cell-induced tumor model. A significant difference in tumor growth and size between in the experimental group and the control groups were detected.Conclusion: The down-regulation of CIAPIN1 expression in tumor was associated with the development of lung carcinoma. Transduction of NCI-H446/A549 CIAPIN1-negative cell, with Ad-CIAPIN1 can inhibit cell growth, alter cell cycle progression, and suppress subcutaneous tumor growth in nude mice, suggesting that CIAPIN1 plays an important role in the development of lung cancer and strengthening the hypothesis of its possible use as a therapeutic target for lung cancer.