ST3GAL2 and nonpapillary renal cell carcinoma: It was shown that the mRNA level of ST3GAL5 was significantly up-regulated in ccRCCs in four datasets and down-regulated in one dataset, compared with normal kidney tissues; while the levels of ST3GAL1, 4 and 6 were down-regulated in ccRCC tissues and no significant expression changes of ST3GAL2 and 3 were observed in ccRCC tissues (Figure 1A, Table 1).