COL18A1 and neoplasm: Similar to luminal cluster 2 in primary tumour, cluster 3 in lung mets, was enriched in a proliferation gene signature (Ran, Cks1b, and Cks2) (Fig. S4), whereas cluster 2 (homologous to cluster 3 in primary tumour), expressed a mesenchymal-like gene set (Col18a1, Vcam1, Col1a1, Vim, Sparc) (Fig. S4).