[1] Katholieke Univ Leuven, Lab Expt Geneeskunde & Endocrinol, B-3000 Louvain, Belgium
[2] Univ Calif Riverside, Dept Biochem, Riverside, CA 92521 USA
[3] Univ Calif Riverside, Div Biomed Sci, Riverside, CA 92521 USA
[4] NCI, Bethesda, MD 20892 USA
[5] Dartmouth Coll Sch Med, Dept Pharmacol, Hanover, NH 03755 USA