Figure 7.

Role of EEA1 in CXCR4-mediated suppression of apoptosis. A, examination of CXCL12-promoted suppression of apoptosis in HeLa cells depleted of EEA1. Cells transfected with control siRNA (siLuc) or siRNAs against EEA1 (siEEA1-1 or siEEA1-2) were left adherent on the culture dish or left detached by seeding onto poly(2-hydroxyethyl methacrylate dishes where cells were unable to adhere. Adherent (Ad) or detached (Det) cells were treated with 10 nm CXCL12 for 2–5 h at 37 °C. Equal amounts of cleared lysates were analyzed by immunoblotting for PARP. Representative immunoblots are shown from four independent experiments. B, immunoblots were analyzed by densitometry. Bars represent the mean of cleaved PARP levels relative to siLuc- and vehicle-treated samples. Error bars represent the S.D. Data were analyzed by two-way ANOVA, followed by Tukey's multiple comparison test. p values are indicated. C, parallel samples from A were examined for caspase-3/7 activity as described under “Experimental procedures.” Bars represent the mean -fold change in caspase-3/7 activity with siLuc-transfected cells that were left adherent to the culture dish and treated with vehicle. Error bars represent the S.D. Single points were removed from the analysis if greater than one S.D. from the mean. Data were analyzed by one-way ANOVA followed by Tukey's multiple comparison test. The p values are indicated. n.s., not significant.