Koiso Y, Fujimoto Y, Matsumura D, Nakajima O, Hashimoto Y
Institute of Molecular and Cellular Biosciences, The University of Tokyo, Japan.
Biol Pharm Bull. 1999 Apr;22(4):439-40. doi: 10.1248/bpb.22.439.
Human myeloid leukemia K562 cells can be induced to differentiate to mature cells bidirectionally, i.e., hemin induces erythroid differentiation, while 12-O-tetradecanoylphorbol 13-acetate (TPA) induces differentiation to monocytes. TPA is also a potent inducer of heme oxygenase (HO), which catabolizes heme to biliverdin. We show here that TPA suppresses hemin-induced erythroid differentiation of K562 cells, while retinoids augment it. Further, an HO inhibitor, tin protoporphyrin (SnPP), suppresses TPA-induced K562 cell differentiation to monocytes. It was also found that co-treatment of K562 cells with SnPP and TPA induces erythroid differentiation of K562 cells, though SnPP alone or TPA alone does not induce erythroid differentiation, suggesting a role of HO in the directional switch of differentiation.
人髓系白血病K562细胞可被双向诱导分化为成熟细胞，即氯化血红素诱导红系分化，而12 - O - 十四烷酰佛波醇 - 13 - 乙酸酯（TPA）诱导分化为单核细胞。TPA也是血红素加氧酶（HO）的强效诱导剂，HO可将血红素分解为胆绿素。我们在此表明，TPA抑制氯化血红素诱导的K562细胞红系分化，而类视黄醇可增强这种分化。此外，一种HO抑制剂，锡原卟啉（SnPP），可抑制TPA诱导的K562细胞向单核细胞的分化。还发现，用SnPP和TPA共同处理K562细胞可诱导K562细胞红系分化，尽管单独使用SnPP或单独使用TPA均不诱导红系分化，这表明HO在分化的方向转换中起作用。
