[Effect of alpha-difluoromethylornithine on growth characteristics and expression of ALT-04ag gene of human lung carcinoma cells].

Objective: To study the effect of polyamine biosynthesis inhibition on growth characteristics of human lung carcinoma cells and its correlation with the expression of human lung carcinoma associated antigen ALT-04ag gene.

Methods: The gene expression was detected by RT-PCR and immunocytochemical tests. The cell growth characteristics were studied by cell growth curves, morphological observation, FCM analysis and DNA electrophoresis.

Results: Human lung squamous carcinoma cells L78 treated with 5 mmol/L alpha-difluoromethylornithine (DFMO) for 5 days showed significant growth inhibition and apoptosis induction. The mRNA and protein expressions of ALT-04ag gene in the cells were downregulated, while these changes resulted from DFMO treatment were prevented by provision of DFMO along with exogenous putrescine.

Conclusion: The effect of polyamine biosynthesis inhibition induced by DFMO restrains the growth characteristics and promotes apoptosis of human lung carcinoma L78 cells, which is associated with down regulation of ALT-04ag gene expression.