Signal transduction of phorbol 12-myristate 13-acetate (PMA)-induced growth inhibition of human monocytic leukemia THP-1 cells is reactive oxygen dependent

Kassim Traore; Michael A Trush; Matthew George Jr; Ernst Wm Spannhake; Winston Anderson; Amha Asseffa

doi:10.1016/j.leukres.2004.12.011

Signal transduction of phorbol 12-myristate 13-acetate (PMA)-induced growth inhibition of human monocytic leukemia THP-1 cells is reactive oxygen dependent

Leuk Res. 2005 Aug;29(8):863-79. doi: 10.1016/j.leukres.2004.12.011. Epub 2005 Feb 24.

Authors

Kassim Traore¹, Michael A Trush, Matthew George Jr, Ernst Wm Spannhake, Winston Anderson, Amha Asseffa

Affiliation

¹ Department of Biochemistry and Molecular Biology, College of Medicine, Howard University, Washington, DC, USA. ktraore@jhsph.edu

PMID: 15978937
DOI: 10.1016/j.leukres.2004.12.011

Abstract

Human monocytic THP-1 cells can be induced to differentiate to macrophages when treated with phorbol 12-myristate 13-acetate (PMA). It is understood that before initiating cell differentiation, PMA treatment must first induce an inhibition of cell growth. Since the initial biochemical and molecular events that are associated with this growth inhibition have not been characterized, the present study was carried out to elucidate the molecular mechanisms associated with the PMA-induced growth arrest of THP-1 cells. Our results indicate that PMA inhibits THP-1 cells at G1-phase of the cell cycle, via a complex mechanism associated with the modulation of the expression of several cell cycle regulators, initiated by the cellular generation of reactive oxygen species (ROS). Both p21WAF1/CIP1 mRNA and protein were upregulated 24 h post PMA treatment as demonstrated by ribonuclease protection assay and Western blotting, respectively. Because these cells lack functional p53, this effect was independent of p53 activity. Electrophoretic mobility shift assay showed that the PMA-induced activation of the p21WAF1/CIP1 promoter was driven by the specific protein 1 (Sp1) transcription factor through Sp1-binding sites. Additionally, our study demonstrates that PMA-induces the upregulation of p21 through a protein kinase C (PKC)-mediated ROS-dependent signaling mechanism involving MAP kinase activation.

Publication types

Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, P.H.S.

MeSH terms

Antioxidants / pharmacology
CDC2-CDC28 Kinases / antagonists & inhibitors
Cell Cycle / drug effects
Cell Cycle Proteins / drug effects
Cell Cycle Proteins / genetics
Cell Cycle Proteins / metabolism
Cell Line, Tumor
Cell Proliferation / drug effects*
Cyclin-Dependent Kinase 2
Cyclin-Dependent Kinase Inhibitor p21
Extracellular Signal-Regulated MAP Kinases / metabolism
Flavonoids / pharmacology
G1 Phase / drug effects
Gene Expression Regulation, Leukemic / drug effects*
Humans
Monocytes / drug effects*
Phosphorylation
Protein Kinase C / metabolism
RNA, Messenger / drug effects
Reactive Oxygen Species / metabolism*
Retinoblastoma Protein / drug effects
Retinoblastoma Protein / metabolism
S Phase / drug effects
Signal Transduction / drug effects*
Tetradecanoylphorbol Acetate / analogs & derivatives*
Tetradecanoylphorbol Acetate / antagonists & inhibitors
Tetradecanoylphorbol Acetate / pharmacology*
Time Factors

Substances

Antioxidants
CDKN1A protein, human
Cell Cycle Proteins
Cyclin-Dependent Kinase Inhibitor p21
Flavonoids
RNA, Messenger
Reactive Oxygen Species
Retinoblastoma Protein
phorbolol myristate acetate
Protein Kinase C
CDC2-CDC28 Kinases
CDK2 protein, human
Cyclin-Dependent Kinase 2
Extracellular Signal-Regulated MAP Kinases
Tetradecanoylphorbol Acetate
2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one