PTK6 Regulates Survival Figure 4. PTK6 downregulation inhibits anchorage-independent survival of breast and ovarian cancer cells. A) PTK6 downregulation inhibits survival of Her2+ cells. The effect of PTK6 downregulation on anchorage-independent survival of MCF-10A cells overexpressing ErbB2 was assessed. Cell death was assessed as in Figure 1. The average fold change in cell death from three independent experiments is shown. Error bars indicate standard deviation. B) PTK6 downregulation inhibits survival of Her2+ breast cancer cells. The effect of downregulating PTK6 on anchorage- independent survival of BT474 cells was assessed. Cell death was assessed as in Figure 1. The average fold change in cell death from three independent experiments is shown. Error bars indicatestandard deviation. C) Downregulation of PTK6 inhibits IGF-1-induced survival of MCF-7 breast cancer cells. The effect of PTK6 downregulation on anchorage-independent survival of IGF-1 (100ng/ml) stimulated MCF-7 breast cancer cell line was assessed in the presence or absence of ZVAD-fmk (25mM). Cell death was assessed as in Figure 1. The average fold change in cell death from three independent experiments is shown. Error bars indicate standard deviation. D) Downregulation of PTK6 inhibits IGF-1 induced survival of DOV-13 ovarian cancer cells. The effect of PTK6 downregulation on anchorage-independent survival of DOV-13 ovarian cancer cells was determined in the presence or absence of IGF-1 (100ng/ml). Cell death was assessed as in Figure 1. The average fold change in cell death from three independent experiments is shown. Error bars indicate standard deviation. doi:10.1371/journal.pone.0011729.g004 changes in several proteins that regulate cell metabolism and growth factor signaling pathways. Downregulation of PTK6 induced an increase in metabolic ‘‘stress’’ as indicated by the enhanced signal intensities for AMPK and phospho-AMPK, and its substrate phospho-ACC. In contrast, there was a decrease in the signal intensities for phospho-Akt, phospho-Erk and phospho- PLoS ONE | www.plosone.org 6 July 2010 | Volume 5 | Issue 7 | e11729