COL3A1 and neoplasm: To understand the gene-expression profiles unique to metastatic cells, we compared the gene-expression profiles in the 2 main clusters (the primary tumor cluster and the metastatic cluster) and identified 298 significantly upregulated DEGs, including members of the collagen gene family (COL1A2 and collagen type III alpha 1 chain [COL3A1]), decorin (DCN), tropomyosin 2 (TPM2), immunoglobulin kappa constant (IGKC), procollagen C-endopeptidase enhancer (PCOLCE), paired related homeobox 1 (PRRX1), actin alpha 2 (ACTA2), and ring finger protein 213 (RNF213; Figs 8D and S5I).