FIG. 8.

A model for Shp-2 functions in promoting cell growth and survival. We and others have shown previously that protein tyrosine phosphatase Shp-2 promotes mitogenic signaling pathways. Evidence is presented in this study that Shp-2 also acts as a survival factor in protecting cells against the cytotoxic effect of IFNs through modulation of Jak/STAT activities. Therefore, we propose a model in which the positive role of Shp-2 in cell growth and survival is contributed by its promotion of mitogenic signals and suppression of Jak/STAT activities.