NUF2 and nonpapillary renal cell carcinoma: We retrieved four microarray data sets from the GEO database (GSE53000 GSE53757, GSE46699, GSE36895) and assessed the expression of NUF2 in ccRCC and normal samples to further validate the authenticity and accuracy of the results of NUF2 expression in ccRCC (Fig. 1C-F).