PT  - JOURNAL ARTICLE
AU  - T Watanabe
AU  - T Mitchell
AU  - E Sariban
AU  - K Sabbath
AU  - J Griffin
AU  - D Kufe
TI  - Effects of 1-beta-D-arabinofuranosylcytosine and phorbol ester on differentiation of human K562 erythroleukemia cells.
DP  - 1985 Jun 01
TA  - Molecular Pharmacology
PG  - 683--688
VI  - 27
IP  - 6
4099  - http://molpharm.aspetjournals.org/content/27/6/683.short
4100  - http://molpharm.aspetjournals.org/content/27/6/683.full
SO  - Mol Pharmacol1985 Jun 01; 27
AB  - We have previously demonstrated that 1-beta-D-arabinofuranosylcytosine (ara-C) induces hemoglobin synthesis in human K562 erythroleukemia cells. The present study extends these findings by demonstrating that ara-C treatment of K562 cells results in both increased heme synthesis and accumulation of alpha-, gamma-, epsilon-, and zeta-globin RNA. The results also demonstrate that ara-C enhances K562 cell surface expression of glycophorin. Furthermore, we demonstrate that phorbol ester (12-O-tetradecanoylphorbol-13-acetate; TPA) inhibits the effects of ara-C on heme production, accumulation of globin RNA, and glycophorin expression. The inhibitory effect occurs maximally when K562 cells are treated with TPA before undergoing ara-C-induced commitment to erythroid differentiation. These findings suggest that TPA inhibits an early step in the process required for ara-C to enhance expression of genes involved in the erythroid program.