Figure 1

Phosphoproteomics classify hematological cell lines according to their tissue origin. Phosphopeptides identified by LC-MS/MS with Mascot and quantified with Pescal in nine hematological cell lines were analyzed by two different clustering tools. (a) Principal component analysis (PCA) of all the cell lines based on the analysis of the most intense 1,500 phosphopeptides. (b) Independent PCA plots of cells belonging to the same pathological group. (c) Unsupervised hierarchical clustering using Kendall's tau coefficient to measure association between peptides and arrays and complete linkage clustering to calculate distances between clusters; AML samples are highlighted in red, lymphoma in blue, and multiple myeloma in green. Each replicate is shown separately and the cell line number is followed by the order in which the samples were analyzed by LC-MS/MS. (d) Summary of phosphopeptides differentially regulated in AML, lymphoma, and multiple myeloma cell lines with two-fold difference over mean expression and P < 0.05 after t-test and FDR multiple test correction.