PCA and heatmap representation of HOXB4-induced expression profiles in BM LSK cells. (A) PCA using all probe sets, where each symbol represents a separate experiment as indicated by the legend, with red symbols denoting HOXB4 samples and blue symbols the GFP controls. The GFP⁺ LSK cells and HOXB4⁺ LSK cells segregate into statistically separate groups across the PC1 axis. HOXB4-LSK cells harvested at 6 weeks are distinct from 12-week and 20-week HOXB4-LSKs across the PC2 axis. (B) Heatmap of gene expression alterations seen across all probe sets, with triplicate samples per experimental arm and time points as indicated by the labels. Red indicates overexpressed probe sets relative to GFP controls, whereas green indicates underexpressed probe sets. PC, principal component.