Figure 3
NCI-60 cell line clustering. (A) Hierarchically clustered correlation matrix of GDF15 gene expression levels by NCI-60 cell lines upon 15 drug treatments. Pearson correlation coefficients were calculated evaluating linear regression slope of GDF15 expression within the first 24 h of drug treatment. Clustering of cell lines was performed using Weighted Pair Group Method with Arithmetic Mean (WPGMA) algorithm based on Pearson correlation coefficients. Four cell line clusters were identified. Tissue types of cell lines are color coded. (B) Drug-specific fraction of responsive NCI-60 cell lines in each identified cell line cluster for 15 anticancer drugs. Responsiveness was assumed when linear regression slope of GDF15 expression within 24 h of drug treatment was > 0.02 and R-squared > 0.5. (C) Predicted basally activated or inhibited pathways for the cell line cluster based on identified differences in gene expression.
