ERBB2 and breast cancer: Using IPA, we researched the expression profiles of the cell cycle-associated genes, signaling pathways associated with cell cycle and signal transduction activities of cell cycle-associate signaling pathways at different time points, and the results showed that signaling pathways of “molecular mechanism of cancer” and “HER-2 signaling in breast cancer” etc. were associated with cell cycle progression, but played different roles at different time points.