Moreover, advanced tumors tended to harbor higher p-PAK1 levels (Figures 1b and c), highly consistent with the finding of O'Sullivan et al.16 In an effort to determine the potential clinical significance of p-PAK1 expression in RCC patients, we quantify the expression levels of p-PAK1 and provide a comparison of clinicopathologic features in dichotomized p-PAK1 status. The gene discussed is PAK1; the disease is renal cell carcinoma.