Fig. 2

Standardization of samples and removal of batch effects. (a) Overall distribution of sample expression from three datasets, which are distinctly different, including data from 16 patients (green), GSE34526 (red), and GSE137684 (blue). (b) Expression levels of the three databases after the removal of batch effects. (c) PCA plots of the three databases before the elimination of batch effects. (d) PCA plots of the three databases after the batch effects have been removed