Inhibition of the G2/M Transition of the Cell Cycle by Methyl- 2,5-dihydroxycinnamate in Human Lymphoid Cells☆☆☆

Abstract Immortalized human lymphoid cells treated with Methyl-2,5-dihydroxycinnamate (MDHC), a stable analog of erbstatin, inhibited the G2/M transition of the cell cycle. The MDHC inhibition of the cell cycle was observed at concentrations well below the IC50 for the inhibition of the EGF receptor and sufficiently below that reported to induce protein cross-linking. The effect of MDHC upon the cell cycle is relatively stable, since unlike erbstatin, inhibition of the G2/M transition was observed 32 hours following removal of the drug. PHA stimulated human peripheral blood mononuclear cells (PBMC) were much less sensitive to MDHC. This study shows that MDHC acts on cells lacking an EGF receptor and the target of MDHC is involved in promoting progression of the cell cycle.