Figure 3

3D Visualization of unsupervised analysis. 3D projection via principal component analysis (PCA) of the clusters obtained with three clustering techniques (K-means, hierarchical clustering, and spectral clustering) applied to the 18 samples representing the 9 cell lines in normoxic (N) or hypoxic (H) conditions using gene expression data of 54613 probesets. The cell lines belonging to the cluster 1 (ACN N/H, SHEP-2 N/H, and GI-ME-N N/H) are represented by yellow stars while the cell lines belonging to the cluster 2 (SK-N-BE(2)C N/H, IMR-32 N/H, SK-N-F1 N/H, LAN-1 N/H, and SK-N-SH N/H) are represented by green triangles.