. Author manuscript; available in PMC: 2011 Apr 8.

Published in final edited form as: Drug Metab Rev. 2010 Feb;42(1):182–194. doi: 10.3109/03602530903208652

Table 4.

Kinetic analyses of O-glucuronidation of anastrozole by UGT1A4 variants.^a

UGT	V_max(pmol·min⁻¹·μg⁻¹)^b	K_m (μM)	V_max/K_m(nL·min⁻¹·μg⁻¹)^b
UGT1A4^24Pro/48Leu	3.6 ± 0.58	637 ± 40	5.6 ± 0.58
UGT1A4^24Thr/48Leu	3.2 ± 0.46	802 ± 137	4.1 ± 1.0
UGT1A4^24Pro/48Val	5.0 ± 1.3	1045 ± 131^*	4.8 ± 0.88

All data are the mean ± standard deviation, based on three independent experiments. Homogenates from cells overexpressing UGT1A8^{173Ala/277Tyr} exhibited no detectable activity against trans-4-OH-TAM and trans-endoxifen. Homogenates from cells overexpressing any of the UGT1A4 variants exhibited no detectable activity against trans-endoxifen.

Data are expressed per μg UGT protein, as determined by Western blot analysis.

P < 0.01.