[Gene transfection of Livin isoforms into A549 cell line and its effect on cell growth and sensitivity to chemotherapy and radiotherapy].

OBJECTIVE: To express Livin alpha & beta in A549 cells by using gene transfection, and to observe its effect on cell growth and cell sensitivity to chemotherapy drugs and radiation. METHODS: Eukaryotic expression vectors of Livin alpha & beta were transfected into A549 cells and cell clones with stable expression were obtained. Livin alpha & beta expression levels in the transfected A549 cells were assessed at mRNA level and protein level, respectively. Cell growth status was assessed by biological features. MTT was performed to test effects of Livin on sensitivity of the A549 cells to chemotherapy drugs and radiation, and cell cycle analysis was performed to evaluate cell apoptosis. RESULTS: After transfection, positive cells, especially A549 cells expressing Livin, showed an increase of about 20% in colony-forming ability, a shorter doubling time (P < 0.05) and lower sensitivity to chemotherapy drugs and radiation (P < 0.01). Only 0.2% of the cells committed apoptosis with 10 Gy radiation. CONCLUSION: Livin isoforms, especially Livin alpha, are implicated in genesis and development of lung cancer, thus may be an important mechanism for drug resistance of lung cancer cells.