TGFB1 and nonpapillary renal cell carcinoma: This ECM remodeling can be profiled by the collagen gene markers COL20A1, COL28A1, TGFB1, COL6A2, COL1A2, and COL4A2. Similarly, metastatic ccRCC progression has been profiled by 17 metastasis-associated gene (MAG) markers identified in a single-cell transcriptomics study conducted on 121 single cells (31, 32).