Figure 1.

PTEN mutation is necessary but not sufficient for PI3Kβ dependence of cancer cell lines. a. We transfected various WT or PTEN mutant cancer cell lines (0.5x10⁶ cells) with 12 or 20 pmol siPIK3CB (depending on cell line) on days 1 and 3 and examined them at day 5. Representative images for 8 cell lines tested. b. Western blot (WB) analysis of extracts from tumor cells as in a.. c. Viability of cells treated with siPIK3CB as in a. and compared to controls (100%). ** P < 0.01, Student's t-test (n ≥ 3). d. Extracts of various tumor cells were tested in WB (indicated). e. Summary of tumor cell responses to PI3Kβ silencing (as a percent of cell survival inhibition), the TP53 and PTEN mutation status, and the ratio of pErk:Erk or E-cad:β-actin signals in d. expressed as a percentage of maximum levels (100%). Cell lines with mutant PTEN and high E-cad levels are underlined.