Influence of recombinant retroviral vector expressing antisense TGF alpha on malignant phenotype of human pancreatic carcinoma cell line.

OBJECTIVE: To observe the effects of antisense TGF alpha on the growth of human pancreatic carcinoma cell line cells. METHODS: A recombinant retroviral vector expressing antisense TGF alpha was constructed, and transfected the ecotropic packaging cell line psi-2 with lipofectin. After the amphotropic packaging cell line PA317 was transfected with the virus supernatant of psi-2, the replication-defective, amphotropic retroviral supernatant was used to infect human pancreatic carcinoma cell line PC-7. Following puromycin selection, puromycin-resistant colonies were pooled and expanded to a cell line PC-7/AS-TGF alpha. RESULTS: The retroviral integration in the genomes of psi-2, PA317 and transformant PC-7 cells was confirmed by Southern blot hybridization. Northern blot hybridization showed a down regulation of endogenous TGF alpha in PC-7/AS-TGF alpha cell line. The high levels of growth inhibition and reduction of 3H-TdR incorporation in PC-7/AS-TGF alpha were evident. Also, the soft agar colony-formation and tumorigenicity in nude mice were significantly suppressed by antisense TGF alpha. CONCLUSION: The antisense TGF alpha expressing vector can block the target gene expression, suppress the cell growth and partially reverse the malignant phenotype of pancreatic carcinoma cells.