Hepatocyte growth factor stimulates cell growth and enhances the expression of transforming growth factor alpha mRNA in AsPC-1 human pancreatic cancer cells

We investigated the effects of hepatocyte growth factor (HGF) and transform ing growth factor alpha (TGF alpha) on cell growth in four human pancreatic cancer cell lines. Changes in the expression of mRNAs of HGF, c-met, TGF a lpha, and epidermal growth factor receptor (EGFR) by treatment with HGF and TGF alpha were observed. Cell growth with growth factors was assessed with the MTT assay and compared with basal growth without growth factors. Altho ugh HGF stimulated cell growth in AsPC-1, COLO-357, and T3M4 cells, Panc-1 cells showed no response to HGF. TGF alpha stimulated the growth of all the above cells. The expression of c-met mRNA under nonstimulated conditions w as detected with Northern blotting in all cells. Treatment with HGF slightl y enhanced the expression of c-met mRNA only in COLO-357 cells. The intensi ty of EGFR expression was consistent, and HGF mRNA was not detected during induction experiments in any cell type. Concomitant treatment with HGF and TGF alpha exerted an effect that was additive or less on the growth of all cells. Expression of TGF alpha was enhanced by HGF treatment only in AsPC-1 cells. These results suggested that HGF and TGF alpha stimulated cell grow th through a final common pathway of signal transduction.