[CIAPIN1 expression in human lung cancer tissues and inhibitory effects of the gene on human pulmonary carcinoma NCI-H446 cells]

To explore CIAPIN1 gene expression in lung carcinoma tissues and its regulatory in the growth of NCI-H446.Fifty-one formalin-fixed paraffin-embedded specimens of primary lung cancer and their non-cancerous counterparts were detected by SABC immunohistochemistry method. Adenoviral vector construction was recombined and the gene was transduced into NCI-H446 cells. The expression of CIAPIN1 protein was identified by Western blot. Trypan blue staining 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.The positive rate of CIAPIN1 expression in cancer tissues (39.2%)was much lower than that in non-cancerous counterparts (100%, P0.05). In Ad-CIAPIN1 group, the growth of transfected NCI-H446 cells in vitro was significantly inhibited. In addition the Ad-CIAPIN1-induced cell apoptosis and a predominant arrest in the G1/S phase (P0.01) were observed.The down-regulation of CIAPIN1 expression in tumor is associated with the development of lung carcinoma. Transduction of NCI-H446 CIAPIN1-negative cell, with Ad-CIAPIN1 can inhibit cell growth, suggesting that CIAPIN1 can be a new tumor-related suppressor gene.