Figure 4: Clustering of the microRNAs by nuclecytoplasmic ratios (NCR) in three cell lines. Hierarchical clustering of microRNAs based on their nucleocytoplasmic integrative variation tendency (See Section 2), and the heatmap of miRNA NCR variation from three cell lines are shown. The small graphs on the right represent cytoplasmic ( -axis) and nuclear ( -axis) expression intensity of six selected miRNAs The red, yellow, and green dots are the MDA-MB-231, MCF-7, and MCF-10A cell lines, respectively.