| Reference | Method | Results |
| P. Apostolou et al. [36] | k-means | 3 clusters identified -Colon cancer cell lines -Normal samples -Stomach, pancreas and liver cancers. |
| J. Gal et al. [37] | -Principal Component Analysis (PCA), -k-sparse -Spectral clustering | 3 risk groups identified for breast cancer -Favorable -Intermediate -Unfavorable |
| J. Xie et al. [38] | PCA | Identifying optimal biomarkers for cancer cell detection |
| F. Yang et al. [39] | PCA | Three subsets are highlighted: -Gastric cells -Plasmacytoid dendritic cells -T-memory cells |