Other genes in the area include PDGFRB, which plays an important role in tumor neovascularization [43], TGFBI [16], PTTG1, DOCK2 and DUSP1 (the latter three genes were speculated based on our internal studies), which were likely to be involved in ccRCC progression and development. Here, PTTG1 is linked to nonpapillary renal cell carcinoma.