Improved coupling between proliferation-arrest and differentiation-induction in ML-1 human myeloblastic leukemia cells.
Proliferation and differentiation are coupled in normal cells and are aberrant in leukemia cells. The studies reported here were aimed at more effectively coupling proliferation-arrest and differentiation-induction in a human myeloblastic leukemia cell line (ML-1). This was accomplished by using reduced serum conditions in conjunction with a differentiation-inducing agent: cells were first incubated in reduced serum [0.3% fetal bovine serum (FBS)] instead of standard conditions (7.5% FBS) and, second, exposed to 12-O-tetradecanoylphorbol-13-acetate (TPA). The effects of this protocol were as follows: first, cell proliferation was slowed and cells accumulated in G0/G1 phase of the cell cycle; this occurred with only a minimal decrease in viability [to approximately 88-92% (0.3% FBS) from greater than or equal to 96% (7.5% FBS)]. Second, the induction of differentiation was accelerated; this allowed the time of exposure to TPA to be decreased. Acceleration of induction was very pronounced when cells were maintained in 0.3% FBS both before and during exposure to TPA, with TPA at concentrations above the minimum sufficient for induction but below those causing significant cytotoxicity; as little as 1 hour of TPA exposure resulted in near-maximal induction (approximately 80%) with this protocol, compared to the greater than or equal to 1 day required with previous standard protocols. In sum, conditions that slow ML-1 cell proliferation (0.3% FBS) enhance TPA-induced differentiation, substantially narrowing the time frame of induction; these conditions should be useful for studying the molecular mechanisms that underlie the induction process.
Kozopas
K M
KM
Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
Buchan
H L
HL
Craig
R W
RW
D002453:Cell Cycle; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D003470:Culture Media; D004273:DNA, Neoplasm / Q000032:analysis; D015870:Gene Expression; D006801:Humans; D007328:Insulin / Q000494:pharmacology; D007700:Kinetics; D015470:Leukemia, Myeloid, Acute; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014168:Transferrin / Q000494:pharmacology
D003470:Culture Media; D004273:DNA, Neoplasm; D007328:Insulin; D014168:Transferrin; D013755:Tetradecanoylphorbol Acetate