Objective:To investigate the expression of c-Myc in non-small cell lung cancer (NSCLC)tissues,and to explore the prospects of the c-Myc gene silencing in NSCLC gene therapy. Methods:The expression levels of c-Myc mRNA in 84 NSCLC tissues and the corresponding para-cancerous tissues were detected by RFQ-PCR(real-time fluorescence quantitative-PCR). C-Myc siRNA was transfected into NSCLC H1299 cells by LipofectAMINE 2000. Cisplatin toxicity experiments further validated effect of inhibiting tumor cells with c-Myc gene silencing. The expression level of c-Myc mRNA in H1299 cells was detected by RT-PCR,and the effect of inhibiting H1299 cells was detected by CCK-8 (Cell Counting Kit-8). Results:The expression level of c-Myc mRNA in NSCLC tissues was higher than that in the corresponding para-cancerous tissues (P < 0.05). C-Myc siRNA was successfully transfected into NSCLC H1299 cells. After transfection,the expression level of c-Myc mRNA was down-regulated in H1299 cells. Effect of inhibiting tumor cells increased significantly when the c-Myc gene silencing and cisplatin were in combination (P < 0.05). Conclusion:The expression level of c-Myc mRNA in NSCLC tissues is higher than that in the corresponding para-cancerous tissues. The lower expression of c-Myc can significantly inhibit NSCLC H1299 cells. It is suggested that c-Myc may act as an oncogene in NSCLC gene therapy.