To further investigate the relationship between RKIP reduction and ccRCC tumorigenesis, a set of tissue microarray (TMA) slides (KD806, KD951, KD2085, KD2088 and KD6161) from US Biomax were used, which contained 45 cases of normal kidney tissues (NKT) and 571 ccRCCs (556 organ-confined tumors without metastasis and 15 carcinomas with metastasis). Here, PEBP1 is linked to nonpapillary renal cell carcinoma.