Glucuronidation is impaired in tumor kidneys. Glucuronidation activity in normal and tumoral kidney homogenates for deferiprone (A), propofol (B), sorafenib (C), mycophenolic acid (D) (specifically the formation of MPA-G), and zidovudine (E). N, normal kidneys homogenates (n = 12), ○; T, tumoral kidney homogenates (n = 14), ●. Paired normal and tumoral samples are connected with a black line. Coefficients of variation (CV) among normal and tumoral samples are given. Detailed quantification data are given in Table 3. **P≤0.01; ***P≤0.001; N.S. not significant.