Alteration of cell cycle progression in @entity1 XXXX cell line (KOPM-28) induced by @entity864 .

@entity1 @entity2799 @entity1778 @entity865 @entity864 @entity616
Terminal cell differentiation usually results in an irreversible arrest in the G1 phase of the cell cycle and loss of cell renewal ability. @entity1 @entity2799 HL-60 cells induced with @entity864 ( @entity865 ) differentiate into monocytes/macrophages and accumulate in G1. We determined the effect of @entity865 on the growth kinetics of a @entity1 @entity1778 cell line (KOPM-28), which developed several of the characteristics of megakaryocytes in response to @entity865 , such as the surface antigen complex IIb/IIIa, platelet peroxidase and polyploidy. Cell growth was immediately and completely inhibited by @entity865 . Flow cytometric analysis of cellular DNA content revealed a gradual decrease in cells in G1 and an accumulation of cells in G2. These data suggest that @entity865 prolonged G1 and rapidly arrested the cells in G2. Synchronized cells were utilized to further analyze the rapid G2 arrest. Cells arrested with aphidicolin at the G1/S interphase were released, and the effects of @entity865 (added at different intervals) on cell cycle progression were examined 14 h after release. The results showed that @entity865 added at the end of the S phase, as well as at the G1/S interphase incompletely but distinctly arrested cells in G2. Moreover, G2 arrest was observed when @entity865 was added to cells released from a colcemid-induced G2/M block, suggesting that cells already in G2 were inhibited by @entity865 from moving through M to G1. Since some cells became multi-nucleated in the course of incubation with @entity865 , this G2 accumulation may have resulted at least in part from a prolongation of the phase or a transient @entity616 . These changes in cell cycle progression induced by @entity865 may be characteristic of and/or related to megakaryocytic differentiation of hemopoietic precursor cells.
