XXXX mustard (melphalan) uptake and cross-linking in the RPMI 6410 human lymphoblastoid cell line.

@entity1522 @entity1160 @entity368 @entity535 @entity10841 @entity3601 @entity6778
@entity10841 mustard (melphalan) induced a time- and concentration-dependent arrest of cycling RPMI 6410 cells in the G2 phase of the cell cycle as evidenced by flow cytofluorometry. A melphalan exposure of 1 microgram/ml for 1 hr caused a temporary G2 blockage which was overcome by 48 hr. Higher concentrations or longer exposures lead to irreversible blockages. Melphalan caused DNA cross-linking which was monitored by the alkaline elution method. The cross-linking was shown to be between DNA and protein. The degree of DNA cross-linking increased for approximately 4 hr after a 1-hr drug exposure of 1 microgram/ml. At 36 to 48 hr after the drug exposure, the cells overcame the G2 block and were dividing. The DNA cross-links have apparently been repaired as they are no longer detected by alkaline elution. The extent of melphalan cross-linking was dependent on both drug dosage and exposure time. Using a culture medium lacking @entity1522 , it was shown that @entity3601 uptake into RPMI 6410 cells was inhibited by @entity368 , @entity6778 , or @entity1160 . The increased uptake of melphalan and the increased cross-linking in @entity535 -deficient media were reduced by readdition of the aforementioned @entity1522 .
