Ethanol Causes Accelerated G1 Arrest in Differentiating HL‐60 Cells

Abstract

The effects of clinically relevant ethanol concentrations on myeloid differentiation in the HL-60 cell promyelocytic leukemia line have been studied. The exposure of noninduced stem cells to 60 mM ethanol results in an increase in G1 cells, but there is no increase in superoxide production or expression of the Mo1 antigen. When HL-60 cells are induced to differentiate along the myeloid line with dimethylsulfoxide (DMSO) or retinoic acid (RA), there is a shift to smaller cell size, an increase in G1 cells and acquisition of the ability to produce superoxide as reported previously by several authors. When ethanol is present during differentiation, there are further increases in G1 cells, and increases in the percentage of cells which produce superoxide and express Mo1, and decreases in mean cell size and total growth during the incubation period. Regrowth experiments after periods of differentiation indicate that the increased G1 arrest seen in the presence of ethanol represents terminal commitment if inducer is present, but in the absence of inducer the increased G1 percentage is readily reversible. Examination of RNA content by flow cytometry reveals a decrease in both the peak and mean G1 RNA content during DMSO or RA induced differentiation. These decreases are accentuated by the presence of ethanol, resulting in a higher G1A/G1B ratio than in nonexposed cells. These findings indicate that ethanol enhances G1 growth arrest in HL-60 cells exposed to myeloid inducers. Partial differentiation occurs during this process, resulting in terminally arrested cells, some of which have undergone fewer postinduction cell divisions than normal and may not be fully competent.

Ethanol-Induced Growth Inhibition of Erythroleukemia Stem Cells

“…It is clear from viability measurements with these cells (legend to figure 1 and other data not shown) that the reduction in growth rate is not due to ethanolinduced cell death. This is consistent with a similar absence of preferential cell death in other ethanolexposed cell lines in vitro [6,9,12,13] at comparable ethanol concentrations.…”

“…HL-60 cells displayed G1A restriction and arrest after ethanol exposure in stem cells and differentiat ing cells, respectively [13]. In the FLC stem cells eval uated here, it is clear that ethanol exposure results in a late G1 restriction after both short-and long-term exposures, but it is unclear whether this is causally related to the rather slow attainment of maximal growth inhibition.…”

“…An increase in G1 cells after ethanol exposure has been reported for several cell lines in vitro under a variety of experimental formats [9,12,13], and a G0/G1 restriction can be inferred from data in regen erating rat liver in which ethanol treatment after par tial hcpatectomy resulted in a substantial reduction in thymidine uptake in the first S phase [14], Analysis of the site of ethanol-induced G1 delay indicates G1A re striction in some rat hepatoma lines [9,12] and GIB or G/S interface restriction in other hepatoma lines [9]. HL-60 cells displayed G1A restriction and arrest after ethanol exposure in stem cells and differentiat ing cells, respectively [13].…”

Alcohol exposure during late gestation adversely affects myocardial development with implications for postnatal cardiac function

“…In this regard a number of in vitro studies have shown that EtOH exposure can lead to alterations in the cell cycle and in cellular differentiation and maturation (10,27). Of particular relevance, Adickes et al (1) found that exposure to EtOH causes cardiomyocytes to become committed to the mature form prematurely.…”

Ethanol Inhibits Fibroblast Growth Factor–Induced Proliferation of Aortic Smooth Muscle Cells

“…Accelerated G 1 arrest and a prolonged S-phase transition have been reported in cells after exposure to ethanol. 26,27 Cell cycle parameters for SV40LT-SMC growth were determined by flow cytometry (the Table). Cells were treated with FGF2 (50 ng/mL) for 24 hours.…”