Re: Yin MB, Li Z-R, Cao S, Durrani FA, Azrak RG, Frank C, and Rustum YM (2004) Enhanced 7-ethyl-10-hydroxycamptothecin (SN-38) lethality by methylselenocysteine is associated with Chk2 phosphorylation at threonin-68 and down-regulation of Cdc6 expression. Mol Pharmacol 66:153-160.