Subsequently, for verifying the close correlation between high A2M expression and angiogenesis in ccRCC patients, the co-immunofluorescence of A2M and vascular endothelial marker Caveolin 1 in tumor tissues from clinical ccRCC patients in the First Affiliated Hospital of Jinan University was detected using the immunofluorescence method. This evidence concerns the gene CAV1 and nonpapillary renal cell carcinoma.