[Effects of antisense cyclin D1 expressing vector on the cell growth and apoptosis of pancreatic carcinoma].

OBJECTIVE: To observe the effects of antisense (AS) cyclin D1 expressing vector on the cell growth and apoptosis of pancreatic carcinoma. METHODS: Examination of the amplification and expression of cyclin D1 in 5 human pancreatic carcinoma cell lines. Our study found the gene amplification and overexpression of cyclin D1 in PC-7 cell line cells. We then constructed the antisense cyclin D1 vector and transfected the PC-7 cell line with lipofectin. The resultant transformant cell line, PC-7/AS-cyclin D1, showed the expression of exogenous antisense cyclin D1 mRNA and down regulation of endogenous cyclin D1 mRNA expression and inhibition of its protein synthesis detected by Northern blot and Western blot respectively. RESULTS: The transformant cells showed retardation of cell growth and partial reversion of the malignant phenotype, including decrease of the rates of cell growth, DNA synthesis, cell proliferation and metabolism, and also the ability of soft agar colony-formation. The tumorogenesis of the transformant cells in nude mice was suppressed. G1 arrest was revealed by flow cytometry. Apoptosis was identified by DNA fragmentation and in situ TUNEL detection. CONCLUSION: Down scaling of the expression of cyclin D1, which plays an important role in the regulation of the cell cycle, can effectively inhibit the proliferation of carcinoma cells and increase cell apoptosis.