In vitro effects of R-verapamil on the cytokine environment and T-lymphocyte proliferation when human T-lymphocyte activation takes place in the presence of acute myelogenous leukemia blasts

 We investigated the effects of R-verapamil on the cytokine environment and T-lymphocyte proliferation when human T-lymphocytes were activated in the presence of accessory cells containing a large population of acute myelogenous leukemia (AML) blasts (nonirradiated blasts for cytokine studies, 50 Gy irradiated blasts in proliferation studies). In the presence of AML blasts, R-verapamil inhibited interleukin 4 (IL4) and interferon-γ (IFNγ) release from polyclonal T-cell lines activated with the T-cell mitogen phytohemagglutinin (PHA). R-verapamil also inhibited both the proliferation and the release of IFNγ and IL10 by normal T-cells stimulated with allogeneic peripheral blood mononuclear cells derived from AML patients. This antiproliferative effect of R-verapamil was seen in the presence of exogenous IL2 but was not observed in the presence of exogenous IL1β or granulocyte/macrophage colony-stimulating factor GM–CSF). In addition R-verapamil inhibited the release of IL1β and tumor necrosis factor α during allogeneic stimulation. Received: 7 January 1996/Accepted: 11 April 1996     

迈清注射液联合化疗治疗急性髓细胞性白血病

目的研究迈清注射液联合化疗治疗急性髓细胞性白血病(AML).方法将急性髓细胞性白血病患者分成两组,一组用普通化疗方案治疗,一组在普通化疗方案治疗的基础上加用迈清注射液,观察两组第二疗程疗效(完全缓解率、部分缓解率及未缓解率)、化疗有效者骨髓幼稚细胞的比例、血象最低值及恢复时间、一年内的复发率.结果迈清注射液组化疗有效者骨髓幼稚细胞的比例低于普通化疗组,前者白细胞恢复时间亦短于后者;但完全缓解率、血象最低值、血小板/恢复时间及一年内的复发率与普通化疗组比则无显著差异.结论迈清注射液能够协助化疗治疗急性髓细胞白血病.     

Short-term remission induction and consolidation therapy for adult acute myelogenous leukemia

One hundred and ninety two adults (median age 44 years) with de novo or secondary (n = 17) acute myelogenous leukemia (AML) were managed with a maximum of six intended courses with adriamycin 25 mg/m2/d for three days, plus cytarabine 200 mg/m2/d and 6-thioguanine 200 mg/m2/d for seven days (short-term therapy, STT). Twenty eight patients not in remission after the first course were given cytarabine 2 g/m2/bd for six days, a treatment that was highly toxic and gave a low CR rate. One hundred and twenty-six patients overall (66 per cent) achieved a complete remission (CR), 117/164 (71 per cent) after one to three standard courses (median 1), and 9/28 (32 per cent) after high-dose cytarabine. Median CR duration was 12 months. By multivariate analysis, younger age, blast count less than or equal to 50 x 10(9)/L, and de novo AML were associated with a better outcome (p less than 0.05). CR duration correlated favourably with FAB M3 morphology and total number (five or six) of cycles (p less than 0.05). In patients receiving five or six total courses, median CR length resulted 15.5 months and leukemia-free survival at 3 years 37 per cent. Therapy was curtailed in one fourth of CR patients because of unacceptable toxicity, and there were nine early deaths attributable to therapy-related complications among 126 CR cases. STT may be a worthwhile form of treatment for patients with de novo non-hyperleukocytic AML that are able to tolerate five or six consecutive induction-like chemotherapy courses.     

复发/难治急性髓系白血病患者P-糖蛋白的表达及功能分析

 目的 研究复发／难治急性髓性白血病（AML）患者P-糖蛋白表达及其功能。方法 用免疫组化方法检测CD34表达,RT-PCR方法检测P-gp的表达,用流式细胞术检测P-gp的功能。结果 CD34表达与P-gp表达、功能呈正相关（r =0.621,P＜0.001;r =0.496,P＜0.001）,P-gp表达与功能呈正相关（r = 0.574,P＜0.01）;复发／难治组CD34阳性率（66.7 %）高于初治组（32.6 %）（P＜0.05）;复发／难治组P-gp功能阳性率（66.7 %）高于初治组（25.6 %）（P＜0.01）。结论 CD34表达、P-gp表达和P-gp功能三者间呈正相关;复发／难治AL组 CD34阳性率、P-gp功能阳性率高于初治组;P-gp功能的检测更具有临床指导意义。     

Microvascular endothelial cells increase proliferation and inhibit apoptosis of native human acute myelogenous leukemia blasts

Interactions between acute myelogenous leukemia (AML) blasts and neighbouring endothelial cells in the bone marrow seem important both for disease development and susceptibility to chemotherapy. We investigated the effects of soluble mediators released by microvascular endothelial cells on native human AML cells. AML cells derived from 33 patients were cocultured with microvascular endothelial cells, separated by a semipermeable membrane. We investigated the effect of coculture on AML cell proliferation, viability/apoptosis and cytokine release. Coculture increased AML cell proliferation, and this growth enhancement included the clonogenic leukemia cell subset. Increased release of several soluble mediators was also detected (interleukin 3, interleukin 6, granulocyte-macrophage and granulocyte colony-stimulating factors) in cocultures. Our cytokine neutralization experiments suggest that an intercellular crosstalk involving several soluble mediators contribute to the increased leukemia cell proliferation. The presence of endothelial cells had an additional antiapoptotic effect on the AML cells. The endothelial cells did not have any growth-enhancing effect on native human acute lymphoblastic leukemia cells. Our in vitro results suggest that the release of soluble mediators by microvascular endothelial cells supports leukemic hematopoiesis through paracrine mechanisms by direct enhancement of AML blast proliferation and by inhibition of leukemic cell apoptosis.     

Effects of 13-cis retinoic acid and Ara-C on differentiation and proliferation of non-promyelocytic acute myelogenous leukemia

An alternative to a cell-kill strategy for eradication of acute myelogenous leukemia, is to restore normal differentiation. Vitamin A derivatives demonstrate differentiation-inducing activity both in vitro and in vivo on promyelocytic leukemic cells. We tested the ability of 13-cis retinoic acid to reduce proliferation and induce differentiation in 10 samples from patients with acute non-promyelocytic leukemia. DNA synthesis and leukemia colony formation were affected to varying degrees by a prolonged exposure to the vitamin A compound. Morphologically and cytochemically no differentiation was determined either after 48 h in suspension cultures or 7 additional days in semi-solid cultures. Alkaline leukocyte phosphatase, a biochemical marker of differentiation, was significantly increased in five samples. DNA synthesis in these samples was significantly reduced as compared to samples failing to express alkaline leukocyte phosphatase following 13-cis retinoic acid treatment. DNA synthesis of these same 5 samples was also strongly inhibited by Ara-C. Expression of alkaline leukocyte phosphatase following 13-cis retinoic acid exposure may be a useful indicator for cells amenable to 13-cis retinoic acid or Ara-C treatment.     

急性髓系白血病合并慢性淋巴细胞白血病一例报道及文献复习

 目的 探讨急性髓系白血病（AML）合并慢性淋巴细胞白血病（CLL）的临床特点、病因、诊断、治疗及预后。方法 临床诊断1例AML合并CLL,并就相关文献进行复习。结果 患者经MA方案（米托蒽醌10 mg／d第1 ~ 3天,阿糖胞苷150 mg／d第1,3,5,7天,200 mg第2,4,6天）化疗后取得完全缓解,但CD19阳性的淋巴细胞（表达CD20,CD23,SIgM,部分表达CD5,CD22,CD25）仍然存在,于9个月后AML复发未能再次缓解而死亡。结论 AML合并CLL为一种具有特殊生物学特征的罕见疾病,免疫分型和细胞遗传学技术在疾病的诊断和认识中发挥重要作用,治疗应以AML为主。     

In vitro effects of native human acute myelogenous leukemia blasts on fibroblasts and osteoblasts

Bone marrow stromal cells constitute a heterogeneous population, and in the present study we investigated intercellular crosstalk via release of soluble mediators between native human AML blasts and fibroblasts/osteoblasts. Coculture of nonleukemic stromal cells and AML blasts separated by a semipermeable membrane decreased proliferation of the fibroblast line HFL1, and the inhibition was maintained when HFL1 and AML cells were cultured in direct contact. A similar inhibitory effect was observed for osteoblastic sarcoma cell lines (Cal72, SJSA-1) and normal osteoblasts. GM-CSF was released by both nonleukemic cells and a subset of AML blast populations, and increased levels of GM-CSF were detected in AML cocultures with fibroblasts and osteoblastic sarcoma cells when testing AML cell populations with constitutive GM-CSF release. Furthermore, constitutive IL-1beta secretion by AML blasts was detected only for a subset of patients, whereas relatively high levels of IL-1RA were observed for all patients; coculture of AML blasts with HFL1 fibroblasts and osteoblastic sarcoma cells increased IL-1beta levels for patients with constitutive IL-1beta secretion, whereas IL-1RA levels were slightly decreased but still generally higher than IL-1beta levels (tested only for HFL1 fibroblasts). The bidirectional crosstalk between AML blasts and stromal cells with increased release of AML growth factors may be important in leukemogenesis, whereas the decreased stromal cell proliferation combined with the persistent release of IL-1RA may in addition inhibit remaining normal hematopoiesis and thereby contribute to bone marrow failure in AML.     

依马替尼对c-Kit+急性髓细胞白血病骨髓细胞凋亡的作用

目的观察依马替尼(STI571)体外对干细胞受体阳性(c-Kit )急性髓细胞白血病(AML)患者骨髓细胞凋亡的作用。方法用RT-PCR法检测c-Kit AML细胞抑凋亡基因SurvivinmRNA和促凋亡基因SmacmRNA的表达水平。结果抑凋亡基因SurvivinmRNA的表达水平下降,促凋亡基因SmacmRNA的表达水平上升。结论STI571能诱导c-Kit AML细胞促凋亡基因SmacmRNA上调,抑凋亡基因SurvivinmRNA的表达水平下降,发挥促凋亡作用。     

Postremission therapy with two different dose regimens of cytarabine in adults with acute myelogenous leukemia

Sixty-seven out of 105 (64%) adults with de novo acute myelogenous leukemia (AML), achieving complete remission after induction chemotherapy, entered two successive postremission treatment protocols. Between 1987 and 1989, 35 patients received an intermediate dose of cytarabine (IDAC) along with other drugs. Between 1990 and 1993, 32 patients received high dose cytarabine (HIDAC) with similar other drugs. Patients treated with IDAC had a median survival of 13.8 months (95% Cl 11.2–23.1 months) and a 2 year survival of 34.3 ± 8.0%. Patients receiving HIDAC had a median survival of 35.5 months (95% Cl, lower limit 29.8 months) and a 2 year survival of 71.6 ± 9.4% (P < 0.002). The 2 year actuarial leukemia-free survival (LFS) was 17.8 ± 6.6% in the IDAC group and 67.3 ± 10.0% months in the HIDAC group (P = 0.004). The HIDAC group had a significant 2 year survival advantage over the IDAC group only in patients younger than 45 years. The 2 year survival in the first group was 83.3 ± 10.8% versus 23.5 ± 10.3% in the IDAC group (P = 0.0001). In patients older than 45 years, no significant differences in 2 year survival was noticed (52.9 ± 15.78 versus 44.4 ± 11.7, P = 0.8). Censoring the 21 patients who underwent bone marrow transplantation (BMT) at BMT did not change significantly the survival analysis of the patients in each group. This study is consistent with previous reports favoring HIDAC intensification in the postremission treatment of young patients with AML.     

Mitoxantrone-associated acute myelogenous leukemia in a patient with high-risk adenocarcinoma of the prostate: a case report and brief review

Background: Mitoxantrone, a topoisomerase II-targeted drug, is used to treat several conditions and is a Food and Drug Administration approved chemotherapeutic agent for the treatment of advanced carcinoma of the prostate. Case Report: A 64-year-old male with high-risk prostate cancer was treated with adjuvant mitoxantrone (12 mg/meter²) every 3 weeks for 6 cycles. Approximately 10 months after finishing therapy, he was diagnosed with an inv [16] Acute Myelogenous Leukemia (AML). Despite aggressive treatment and support, the patient had a rapidly fatal clinical course. Conclusion: Despite its regular use in this setting, this is the first reported case of treatment-associated AML after mitoxantrone in prostate cancer.     

白细胞介素-11防治急性髓系白血病化疗后血小板减少的临床研究

  目的 观察重组人白细胞介素-11（rhIL-11）防治急性髓系白血病化疗后血小板减少的疗效及其不良反应。方法 采用自身对照研究的方法，对21例因化疗引起血小板减少（＜50×109／L）急性髓性白血病患者给予rhIL-11预防性治疗。第1周期单用化疗；第2周期化疗联合rhIL-11，即化疗结束后24 h开始用rhIL-11，25μg／kg，皮下注射，1次／d，连续用药14 d或连续2次检查血小板计数≥300×109／L停药。结果 共入选21例患者，2例因第1周期化疗后疾病进展，中止化疗而剔除，19例可评价疗效和毒性反应。对照周期：化疗后血小板最低值（31.9±9.2）×109／L，血小板＜50×109／L平均天数（8.9±3.3）d，输注同型异体血小板7例次。研究周期：化疗后血小板最低值（56.4±17.8）×109／L（P＜0.05），血小板＜50×109／L平均天数（4.6±2.9）d（P＜0.05），输注同型异体血小板3例次。结论rhIL-11可提高血小板最低值，缩短血小板减少持续时间、减少血小板输注量，耐受性良好。     

Acute myelogenous leukemia stem cells: From Bench to Bedside

Despite reaching remission with traditional chemotherapy, most adult patients with acute myeloid leukemia (AML) will relapse and die of their disease. Numerous studies have identified a rare subset of leukemia cells that evade traditional chemotherapy and are capable of self-renewal and initiating leukemia. These cells are thought to be responsible for relapse and are termed leukemia stem cells (LSCs). This article will review the current LSC translational research and focus on new approaches to detect LSC burden and its prognostic implications, as well as the identification and development of therapeutic agents active against LSCs.     

Stress-induced in vitro apoptosis of native human acute myelogenous leukemia (AML) cells shows a wide variation between patients and is associated with low BCL-2:Bax ratio and low levels of heat shock protein 70 and 90

Spontaneous in vitro apoptosis reflects a true biological heterogeneity between patients which has to be considered when in vitro models are used to study regulation of apoptosis in native human AML cells. Even though the balance between pro- and anti-apoptotic signaling seems to have a prognostic impact in AML, the possible clinical relevance of spontaneous apoptosis remains to be clarified. High apoptosis/low viability was associated with low levels of heat shock proteins 70 and 90 as well as low Bcl-2:Bax ratio for patients heterogeneous with regard to morphology, membrane molecule expression, genetic abnormalities and response to therapy.     

Estimation of the prevalence of Fanconi anemia among patients with de novo acute myelogenous leukemia who have poor recovery from chemotherapy

We speculated that some individuals with de novo acute myelogenous leukemia (AML) may have undiagnosed Fanconi Anemia (FA). Data from patients enrolled on AML protocol CCG-2961, published FA cohort studies, SEER, and Bayes rule were used to estimate the probability of FA among all newly diagnosed AML cases, and among those who had no or delayed recovery of the absolute neutrophil count following initial chemotherapy. We determined that the probability of undiagnosed FA in patients in a treatment trial for newly diagnosed patients was around 0.18%, and around 0.83% in the subset who had poor marrow recovery. We suggest that FA or other inherited bone marrow failure syndromes be considered prior to treatment, or certainly among those with poor recovery.     

Cholesterol catabolism in patients with acute myelogenous leukemia and hypocholesterolemia: suppressed levels of a circulating marker for bile acid synthesis

Hypocholesterolemia is a frequent finding in patients with acute myelogenous leukemia (AML) and in other types of malignancies. Since bile acids are major excretion products of cholesterol, the hepatic degradation of cholesterol to bile acids was investigated in AML patients by analyzing a circulating marker for bile acid synthesis. In addition, plasma levels of a marker for cholesterol synthesis were determined. The plasma levels of 7-hydroxy-4-cholesten-3-one, reflecting bile acid production, were markedly lower in patients with AML than in healthy controls. The median levels were 3.3 and 18.5 ng/ml (P<0.0001) in the AML patients (n=29) and the healthy subjects (n=16), respectively. The plasma levels of 7-dehydrocholesterol, reflecting hepatic cholesterol synthesis, were similar for the AML patients and the controls. The results show that the conversion of cholesterol to bile acids was suppressed in AML patients, a phenomenon that may result in a decreased intestinal absorption of cholesterol and subsequent hypocholesterolemia.     

Flt3 in acute myelogenous leukemia

Flt3 is a tyrosine kinase receptor expressed on hematopoietic cells. Activating mutations of this receptor are encountered in over one-fourth of acute myelogenous leukemia (AML) cases and activate multiple intracellular pathways leading to cell proliferation, inhibition of apoptosis, and blockage of differentiation in leukemic blasts. AML with flt3 mutations has a worse prognosis than AML with normal flt3, at least in younger patients. Sevaral flt3 inhibitors are in various stages of preclinical and clinical development and it is hoped that specific therapies against AML with flt3 mutations will soon be available to the clinician.     

Monensin-mediated growth inhibition in acute myelogenous leukemia cells via cell cycle arrest and apoptosis

Monensin, an Na(+) ionophore, regulates many cellular functions including apoptosis. However, there has been no report about the antitumoral effect of monensin on acute myelogenous leukemia (AML). Here, we investigated the antiproliferative effect of monensin on AML cells in vitro and in vivo. Monensin efficiently inhibited the proliferation of all of 10 AML cell lines, with IC(50) of about 0.5 microM. DNA flow cytometric analysis indicated that monensin induced a G(1) and/or a G(2)-M phase arrest in these cell lines. To address the mechanism of the antiproliferative effect of monensin, we examined the effect of monensin on cell cycle-related proteins in HL-60 cells. The levels of CDK6, cyclin D1 and cyclin A were decreased. In addition, monensin not only increased the p27 level but also enhanced its binding with CDK2. Furthermore, the activities of CDK2- and CDK6-associated kinases reduced by monensin were associated with hypophosphorylation of Rb protein. Monensin also induced apoptosis in AML cells including HL-60 cells. The apoptotic process of HL-60 cells was associated with changes in Bax, caspase-3, caspase-8 and mitochondria transmembrane potential (Deltapsi(m)). In particular, monensin (i.p. at a dose of 8 mg/kg thrice weekly) significantly reduced the tumor size of BALB/c mice that were inoculated s.c. with its derived cell line, WEHI-3BD cells (69% growth inhibition relative to control group; p < 0.05). Tumors from monensin-treated mice exhibited increased apoptosis, and these tumor were immunohistochemically more stained with Bax, Fas and p53 antibodies than control tumors. In conclusion, this is the first report that monensin potently inhibits the proliferation of AML cells.     

Chronic myelogenous leukemia cells convert to myofibroblasts in vitro: effect of vascular endothelial growth factor on development of the microenvironment

To elucidate the biological characteristics of chronic myelogenous leukemia (CML) cells, we observed morphological and functional changes of CML cells during primary long-term culture, in which their morphology changed to that of myofibroblasts with similar molecular characteristics to the parental CML cells including BCR-ABL fusion gene, and produced cytokines such as granulocyte colony-stimulating factor, interleukin-6, and vascular endothelial growth factor (VEGF)-A. When cultured on the CML-derived myofibroblasts, parental non-adherent CML cells significantly proliferated. When anti-VEGF-A-neutralizing antibody was added to the cultures, non-adherent CML cell proliferation was significantly inhibited. These observations indicate that CML cells can convert their morphology and function to adherent myofibroblasts, and produce a significant amount of cytokine to give a growth-promotion activity to CML cells.