Tafuri A, De Felice L, Petrucci M T, Mascolo M G, Ricciardi M R, Ciliberti C, Martelli M P, Petti M C
Department of Human Biopathology, Università di Roma La Sapienza, Italy.
Cytokines Mol Ther. 1995 Dec;1(4):301-7.
Fourteen poor risk acute myeloid leukemia (AML) patients were treated with G-CSF prior (from day 0) and during chemotherapy with fludarabine and Ara-C from day 1 to day 5 (the FLAG regimen). Several biological parameters were monitored on the blast population: multidrug resistance (MDR) functional expression by rhodamine-123 efflux (Rhd-E), cell cycle changes, induction of apoptosis and leukemic clonogenic cell growth (CFU-L). The mean basal Rhd-E value was 14.4% (range 0-51.2), and 12/14 patients exhibited a dye efflux > 4%, efficiently blocked by the MDR-reversal agent cyclosporin A. After 24 h of G-CSF administration, cell cycle studies showed in bone marrow (BM) samples a significant mean increase in S phase (p = 0.04) and in RNA content of G1 cells (p = 0.01), coupled to a significant increase in apoptosis (p = 0.02). Clonogenic cell growth analysis showed a twofold increase in BM CFU-L in 6 of the 14 cases tested. When G-CSF activity was assessed without the addition of exogenous growth factors (autonomous proliferation), a significant increase (p = 0.02) in CFU-L was found only in patients who achieved a complete remission (CR); these patients were also characterized by lower S-phase values at diagnosis. Eight of the 14 patients treated achieved CR, but the median response duration was three months, and only two cases are still in CR. The FLAG regimen can thus induce remission in poor risk AML patients. The responses, however, are short, suggesting that resistant cells are not efficiently affected by either the use of agents not involved in the MDR-efflux mechanism or by the G-CSF priming strategy. Other post-induction therapies need to be considered in further approaches.
14例预后不良的急性髓系白血病（AML）患者在化疗前（从第0天开始）接受粒细胞集落刺激因子（G-CSF）治疗，并在第1天至第5天接受氟达拉滨和阿糖胞苷化疗（FLAG方案）。对原始细胞群体监测了几个生物学参数：通过罗丹明-123外排（Rhd-E）检测多药耐药（MDR）功能表达、细胞周期变化、凋亡诱导以及白血病克隆形成细胞生长（CFU-L）。基础Rhd-E的平均值为14.4%（范围0-51.2），14例患者中有12例染料外排>4%，多药耐药逆转剂环孢素A可有效阻断。给予G-CSF 24小时后，细胞周期研究显示骨髓（BM）样本中S期平均显著增加（p = 0.04），G1期细胞的RNA含量显著增加（p = 0.01），同时凋亡显著增加（p = 0.02）。克隆形成细胞生长分析显示，在14例检测病例中的6例，BM CFU-L增加了两倍。当在不添加外源性生长因子的情况下评估G-CSF活性（自主增殖）时，仅在达到完全缓解（CR）的患者中发现CFU-L显著增加（p = 0.02）；这些患者在诊断时也具有较低的S期值。14例接受治疗的患者中有8例达到CR，但中位缓解持续时间为3个月，仅有2例仍处于CR状态。因此，FLAG方案可诱导预后不良的AML患者缓解。然而，缓解期较短，这表明耐药细胞未被未参与MDR外排机制的药物使用或G-CSF预处理策略有效影响。在进一步的治疗方法中需要考虑其他诱导后治疗。
