[1] NCI, Med Oncol Branch, Bethesda, MD 20892 USA
[2] NCI, Med Oncol Branch, NIH, Bethesda, MD 20892 USA
[3] NCI, Bethesda, MD 20892 USA
[4] NCI, Canc Prevent Div, Bethesda, MD 20892 USA
[5] NCI, Rockville, MD USA
[6] NCI, Mol Pharmacol Sect, NIH, Bethesda, MD 20892 USA