Production of transforming growth factor alpha in human pancreatic cancer cells: evidence for a superagonist autocrine cycle.

摘要: Abstract Previous work showed that cultured human pancreatic cancer cells overexpress the epidermal growth factor (EGF) receptor. In present study, we sought to determine whether some of these cell lines produce transforming alpha (TGF-alpha). Utilizing a radiolabeled TGF-alpha cDNA in hybridization experiments, determined ASPC-1, T3M4, PANC-1, COLO-357, and MIA PaCa-2 expressed mRNA. Serum-free medium conditioned by T3M4 ASPC-1 contained significant amounts protein. Although unlabeled readily competed with 125I-labeled EGF for binding, each line exhibited lower surface binding internalization as compared EGF. Both significantly enhanced anchorage-independent cells. However, was 10- 100-fold more potent than These findings suggest concomitant overexpression receptors production may represent an efficient mechanism certain obtain advantage.