SPSS (SPSS, Inc.) and Microsoft Excel were used for statistical analysis of data. The two-tailed Student t-test was used to determine statistical significance in experiments comparing protein-treated cells versus untreated cells, with a Pvalue of less than 0.05 as a cutoff. One-way ANOVA was used to determine statistical significance of dose-response assays, with a P-value of less than 0.01 as a cutoff. All data are representative of at least three independent experiments.