A2M and nonpapillary renal cell carcinoma: Specifically, the single-cell sequencing results were analyzed and it was found that A2M was primarily expressed in mononuclear phagocytes (MNPs), endothelial cells, fibroblasts, and proliferating cells in ccRCC dataset GSE152938; the single-cell expression position of a few leukocyte marker CD45 and T cell marker CD3 overlapped with the expression position of A2M, which suggested that A2M may be related to MNPs and T cells in immune cells, with a more close relation to MNP (Figure 5B).