Fig. 4.

Cancer tasks partly explain intratumor heterogeneity. a Projecting single-cancer cells from different breast tumors onto the tetrahedron defined by metabric breast tumors shows that single-cancer cells from the same tumor can be generalists and specialists at different tasks. b Intertumor diversity varies mainly along the first two principal components (PC) of the metabric tumors: the first two PC explain 11.1 and 8.1% of the variance in gene expression between tumors whereas PC50 explains only 0.2% tumors thus fall on a plane within the volume defined by PC1, PC2, and PC50. c Projecting single cancer cells from different breast tumors onto PCs from metabric tumors shows that intratumor heterogeneity is aligned with intertumor diversity. d Intertumor diversity explains a significant fraction of intratumor variance. PCs computed on metabric tumors explain 25.4% of the variance explained by PCs computed on single cells. PCs computed on a shuffled version of the metabric data explain only 1.5% of the variance explained by single-cell PCs. Black dots represent different tumors. P-value from the T test. Data: gene expression in Metabric tumors from Curtis et al.⁵, single-cell gene expression in six breast tumors from Karaayva et al.⁴⁷.