te Boekhorst P A, Löwenberg B, Vlastuin M, Sonneveld P
Department of Hematology, Erasmus University, Rotterdam, The Netherlands.
Leukemia. 1993 Aug;7(8):1191-8.
Exposure to hemopoietic growth factors (HGFs) induces proliferation of clonogenic acute myeloid leukemia (AML) cells. Recruitment of quiescent, clonogenic blasts may improve the cytotoxic effects of cell-cycle-specific drugs like cytosine arabinoside (Ara-C). Because other studies have shown heterogeneous effects of HGF and Ara-C incubation, we analyzed the individual effects of granulocyte colony-stimulating factor (G-CSF), interleukin 3 (IL-3), and granulocyte-macrophage colony-stimulating factor (GM-CSF) combined with an S-phase and non-phase specific cytostatic agent on clonogenic blasts of 14 newly diagnosed AML patients under standardized, serum-free conditions. AML cells were incubated for 24 hours with titrated concentrations of Ara-C (0.01, 0.1, 1 microM) or mafosfamide (0, 1.0, 10, or 20 micrograms/ml) following preincubation for 48 hours with or without G-CSF, IL-3, or GM-CSF, starting at 24 hours prior to chemotherapy exposure. AML colony-forming cells (AML-CFU) were then determined in semi-solid culture in the presence of the same growth factor. The results showed significantly enhanced cytotoxicity of Ara-C to AML-CFU following stimulation by G-CSF (p < 0.002 at 0.01 microM, p < 0.002 at 0.1 microM, and p < 0.01 at 1 microM Ara-C), IL-3 (p < 0.002 at 0.01 microM, p = 0.001 at 0.1 microM, p < 0.01 at 1 microM, Ara-C), and GM-CSF (p = 0.01 at 0.01 microM, p < 0.01 at 0.1 microM, and p < 0.002 at 1 microM Ara-C). A moderate but significant enhancement of mafosfamide cytotoxicity by HGF was also observed (p < 0.05 at 1.0 microgram/ml mafosfamide by IL-3 and GM-CSF and p < 0.05 at 10 micrograms/ml mafosfamide by GM-CSF). Ara-C cytotoxicity to normal bone marrow progenitors was enhanced significantly only by G-CSF (p = 0.02 at 0.01 microM, p = 0.01 at 0.1 microM and p < 0.01 at 1 microM Ara-C), and by GM-CSF at 0.1 microM Ara-C (p = 0.045). However, the effect of HGF stimulation as studied by bromodeoxyuridine (BrdU) incorporation during the first or second 24 hours of HGF stimulation did not explain the difference between poor and good HGF enhanced Ara-C cytotoxicity, indicating that other cellular changes than cell-cycle activation as the consequence of growth factor stimulation are responsible for enhanced cytotoxicity. Our findings indicate that combining HGFs, and especially IL-3, with chemotherapy may be useful in the AML treatment.
暴露于造血生长因子（HGFs）可诱导克隆性急性髓系白血病（AML）细胞增殖。募集静止的克隆性母细胞可能会增强细胞周期特异性药物（如阿糖胞苷，Ara-C）的细胞毒性作用。由于其他研究显示HGF与Ara-C孵育存在异质性效应，我们在标准化无血清条件下，分析了粒细胞集落刺激因子（G-CSF）、白细胞介素3（IL-3）和粒细胞-巨噬细胞集落刺激因子（GM-CSF）与一种S期和非S期特异性细胞抑制剂联合作用于14例新诊断AML患者的克隆性母细胞的个体效应。在化疗暴露前24小时开始，AML细胞先与G-CSF、IL-3或GM-CSF预孵育48小时，然后再与滴定浓度的Ara-C（0.01、0.1、1微摩尔）或马法兰（0、1.0、10或20微克/毫升）孵育24小时。随后在存在相同生长因子的半固体培养中测定AML集落形成细胞（AML-CFU）。结果显示，G-CSF刺激后Ara-C对AML-CFU的细胞毒性显著增强（0.01微摩尔Ara-C时p<0.002，0.1微摩尔时p<0.002，1微摩尔Ara-C时p<0.01）、IL-3刺激后（0.01微摩尔Ara-C时p<0.0,02，0.1微摩尔时p = 0.001，1微摩尔Ara-C时p<0.01）以及GM-CSF刺激后（(0.01微摩尔Ara-C时p = 0.01，0.1微摩尔时p<0.01，1微摩尔Ara-C时p<0.002）。还观察到HGF使马法兰细胞毒性有适度但显著的增强（IL-3和GM-CSF作用于1.0微克/毫升马法兰时p<0.05，GM-CSF作用于10微克/毫升马法兰时p<0.05）。Ara-C对正常骨髓祖细胞的细胞毒性仅在G-CSF刺激下显著增强（0.01微摩尔Ara-C时p = 0.02，0.1微摩尔时p = 0.01，1微摩尔Ara-C时p<0.01），以及GM-CSF作用于0.1微摩尔Ara-C时（p = 0.045）。然而，通过在HGF刺激的第一个或第二个24小时内掺入溴脱氧尿苷（BrdU）研究的HGF刺激效应并不能解释HGF增强Ara-C细胞毒性好坏之间的差异，这表明除了生长因子刺激导致的细胞周期激活外，其他细胞变化是增强细胞毒性的原因。我们的研究结果表明，将HGFs，尤其是IL-3与化疗联合应用可能对AML治疗有用。
