Fig. 3
![Fig. 3](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs12967-018-1589-1/MediaObjects/12967_2018_1589_Fig3_HTML.png)
a Volcano plot of the gene expression profile data of all 18 patients. x-axis reports difference of the group means while y-axis indicates statistical significance of the t-test per rows (–\(\log _{10}\) of p-value). The dashed line shows where \(p = 0.05\) with points above the line having \(p < 0.05.\) In particular, points represent interesting genes, in the left upper corner are depicted genes with mostly small p-value and low difference in means, whereas in the right upper corner there are genes with small p-value and large difference in means. b Heatmap of the first principal component PC1 and of the Metagene 1 (both normalized) obtained respectively by PCA and NMF on the gene expression profile data of all 18 patients