Potentiated maturation with a high proliferating activity of acute promyelocytic leukemia induced in vitro by granulocyte or granulocyte/macrophage colony-stimulating factors in combination with all-trans retinoic acid

All-trans retinoic acid (ATRA) induces differentiation of acute promyelocytic leukemia (APL), but the effect of cytokines regulating myeloid differentiation on ATRA-induced APL cells is poorly understood. In this study, maturation and proliferation of fresh APL cells were examined when induced in vitro by granulocyte or granulocyte/macrophage colony-stimulating factors (G-CSF or GM-CSF) in combination with ATRA. APL cells showed a low proliferating activity when induced by ATRA alone. In contrast, cells induced by G-CSF or GM-CSF alone showed increased DNA syntheses, the levels of which were not significantly affected by the combination of ATRA with CSFs. Interestingly, G-CSF or GM-CSF potentiated the capability of ATRA-induced cells to reduce nitroblue tetrazolium (NBT), while G-CSF or GM-CSF alone induced no NBT reduction. Furthermore, in several patients examined, APL cells induced by ATRA with G-CSF showed an increased activity of chemotaxis and CD11a expression. These findings suggest that G-CSF or GM-CSF can potentiate differentiation of ATRA-induced APL cells while stimulating their proliferating activity as well, and that G-CSF, rather than GM-CSF, may be a useful adjunct to promote ATRA-induced differentiation of APL.     

Differentiating therapy in acute myeloid leukemia

Differentiating therapy is a new antineoplastic strategy which has received increasing attention due to the remarkable activity of the vitamin A derivative, all-trans retinoic acid (ATRA) in patients with acute promyelocytic leukemia (APL). Although it has been known for years that a variety of agents, including retinoids, could induce leukemic cells to differentiate in vitro, it was not until the initial report from Shanghai in 1988 that laboratory studies translated into clinical activity and benefit in patients. Since this initial report, a number of studies have confirmed that the majority of patients with both newly diagnosed and previously chemotherapy-treated patients with APL achieve complete remission (CR) with ATRA. In addition, the characteristic life-threatening coagulopathy resolves quickly. Several limitations to this approach have emerged, including the development of retinoid resistance, hyperleukocytosis and the retinoic acid syndrome, a constellation of findings including unexplained fever, fluid retention, pleuropericardial effusions and pulmonary infiltrates. Although ATRA is very effective in inducing CR, its benefits compared to conventional chemotherapy are only now being addressed. The first prospective randomized trial comparing ATRA plus chemotherapy to chemotherapy alone was terminated early because of an improved event-free survival for patients receiving ATRA. The benefit was attributable to a difference in relapse rate. A large, intergroup, prospective, randomized trial comparing conventional chemotherapy to ATRA for induction and ATRA to observation for maintenance has recently completed accrual and will provide insight into the emerging role of ATRA in patients with APL. ATRA represents the first example of a specific form of antileukemic therapy targeting a specific genetic abnormality and may serve as a paradigm for the development of differentiating therapy for patients with other hematologic malignancies.     

Acute promyelocytic leukemia: all-trans retinoic acid (ATRA) along with chemotherapy is superior to ATRA alone

This study was conducted to compare the results of treatment of acute promyelocytic leukemia (APL) with all-trans retinoic acid alone (ATRA) or a combination therapy of ATRA followed by chemotherapy. Forty-three patients treated between February 1992 and February 1996 were included in this study. Eighteen patients were treated with ATRA alone and 25 patients were treated with ATRA followed by chemotherapy. The cytogenetic analysis was done in 41 patients at presentation, following treatment, and at follow-up. A complete response (CR) was achieved in 13 (72%) patients on ATRA and 19 (76%) on ATRA followed by chemotherapy. Eleven of 13 patients with response to ATRA alone relapsed with median survival of eight months (range, 1 to 28). One patient died of hepatitis in CR and one patient is alive 2 years after diagnosis. In the combination therapy arm, 10 patients are in CR with a median follow-up of 22 months (range, 6 to 56 months). After achieving a CR, four patients died due to infections during chemotherapy therapy, and only 5 of 19 patients have relapsed. Major cytogenetic response was seen in 8 of the 10 patients in whom cytogenetic data was available after treatment with ATRA at the time of remission. Similarly, 13 of 15 for whom data was available showed a major cytogenetic response after treatment with ATRA plus chemotherapy. Prior to relapse, 80% of the patients had an increase in the percentage of t(15;17) cells in the marrow. Patients with a complete hematological response but no cytogenetic response relapsed within six months. Ten patients died prior to response evaluation. Two patients who received ATRA died of retinoic acid syndrome, one of pneumonia, and one of intracranial hemorrhage. Of the six patients on ATRA and chemotherapy, four died of retinoic acid syndrome (RAS), one of intracranial hemorrhage, and one of left ventricular failure. Only one patient is alive at 24 months following treatment with ATRA alone. The relapse-free survival is 42% at four years for patients treated with ATRA followed by chemotherapy. This trial is a historical comparison of ATRA alone and ATRA with subsequent combination chemotherapy. Nonetheless, the trial shows a significant improvement in the event free survival of patients receiving chemotherapy as consolidation following ATRA.     

Treatment of newly diagnosed acute promyelocytic leukemia (APL) by all transretinoic acid (ATRA) combined with chemotherapy: The European experience. European APL Group

All transretinoic acid (ATRA) gives complete remission (CR) rates of 80 to 90% in newly diagnosed acute promyelocytic leukemia (APL). However, it has two major drawbacks (1) a rapid rise in WBC in some patients, with potentially fatal ATRA syndrome (2) rapid relapse with maintenance therapy using ATRA alone or low dose chemotherapy. The French APL group therefore designed a treatment approach with ATRA followed by intensive chemotherapy. The latter was administered after CR achievement with ATRA, or was rapidly added to ATRA in case of rapid rise in leukocyte counts. This combined approach, in a pilot study and in a randomized trial, proved superior to intensive chemotherapy alone, by slightly increasing the CR rate but more importantly by reducing the relapse rate. These results were confirmed by the Chinese, Japanese and New York groups. Our group (and other European groups) are now testing in a new randomized trial the better timing of ATRA and chemotherapy administration (ATRA followed by chemotherapy or ATRA plus chemotherapy) and the role (after an intensive consolidation) of maintenance treatment with intermittent ATRA, continuous low dose chemotherapy or both.     

Treatment of acute promyelocytic leukemia--combined use of all-trans retinoic acid and granulocyte colony-stimulating factor

We evaluated the effect of treatment by all-trans retinoic acid (ATRA) in 9 patients with acute promyelocytic leukemia (APL). Of 6 patients who had circulating leukemic blasts before treatment, 3 initially received ATRA alone but died of respiratory failure due to retinoic acid syndrome (RAS). High dose steroid therapy did not rescue RAS in these patients. Another 3 who were given intensive chemotherapy followed by ATRA and/or granulocyte colony-stimulating factor (G-CSF) achieved complete remission (CR). Of 3 patients without peripheral leukemic blasts before treatment, 1 received intensive chemotherapy followed by G-CSF and reached CR, 1 who had been previously given ATRA did not respond to ATRA, and 1 did not initially respond sufficiently to ATRA alone but responded dramatically to ATRA plus G-CSF. In the treatment of APL, appropriate combination of ATRA, G-CSF and chemotherapy should always be taken into consideration. In addition, RAS have to be carefully avoided when applying ATRA therapy in patients who have circulating leukemic blasts before treatment.     

复方黄黛片治疗急性早幼粒细胞白血病的系统评价

目的 评价复方黄黛片( CRNTT)治疗急性早幼粒细胞白血病(APL)的疗效与安全性。方法计算机检索SinoMed、CNKI、VIP、万方、CBA、PubMed、MEDLINE、EMBASE、Cochrane图书馆临床对照试验资料库,并辅以手工检索,收集国内外公开发表的CRNIT治疗APL的随机对照试验(RCT)文献,检索年限截至201 1年3月。按纳入标准与排除标准筛选文献并评价纳入研究的质量,以完全缓解(CR)率、达CR所需时间、复发率、病死率、不良反应率等为评价指标,采用RevMan 5.1软件进行Meta分析。结果纳入6项RCT,包括391例APL患者,其中2项RCT研究目的为CRNIT与三氧化二砷(ATO)的比较,4项RCT研究目的为CRNIT与全反式维甲酸(ATRA)的比较,其中1项RCT增设CRNIT+ ATRA与ATRA的比较。达CR所需时间：CRNIT比ATRA、ATO长[加权均数差(WMD)=3.14,95％CI 0.99 ～5.29,P=0.004];头痛发生率：CRNTT低于ATRA（OR=0.10,95％CI 0.02～0.45,P=0.003）;5年无病生存率：CRNIT优于ATRA（OR= 7.22,95％CI 1.40～37.25,P=0.02）;CR率、复发率、病死率和4项不良反应指标（胃肠道症状、肝肾功能损害、皮肤损害、发热）的Meta分析结果差异无统计学意义。结论服用CRNIT达CR所需时间比ATRA、ATO长,CRNIT近期疗效与ATRA、ATO相近。服用CRNIT的5年无病生存率可能优于ATRA。     

三氧化二砷联合全反式维甲酸治疗初发急性早幼粒细胞白血病50例疗效观察

目的 观察三氧化二砷(ATO)联合全反式维甲酸(ATRA)治疗初发急性早幼粒细胞白血病(APL)的疗效.方法 98例初发APL患者分为对照组和治疗组,对照组48例,治疗组50例.对照组采用常规ATRA+DA双诱导方案治疗;治疗组采用ATRA每天25 mg/m2,ATO每天0.15 mg/kg(ATRA后第10天开始)联合治疗,直至完全缓解(CR),CR后接受ATO和ATRA联合巩固治疗.比较两组CR率、PML-RAR α融合基因转阴时间及5年无病生存率.结果 对照组和治疗组CR率分别为89.5%(43/48)和90.0%(45/50),获得CR时间分别为(30.0±5.1)d和(28.1±4.4)d,两组CR率(x2=-0.068,P=0.946)及获得CR时间(t=1.757,P=0.083)相比差异均无统计学意义.在所有获得CR的患者中,3例分别在CR后第276、385和394天复发.所有患者发病时PML-RAR α融合基因均阳性,对照组和治疗组CR时分别有25.0%(5/20)和29.4%(5/17)转阴,巩固后分别有92.5%(37/40)和97.6%(41/42)转阴.对照组和治疗组5年无病生存率分别为(85.3±5.9)%和(87.6±5.6)%,差异无统计学意义(x2=0.232,P=0.630).结论 ATO联合ATRA能有效治疗初发APL患者,可以作为常规化疗方案外的另一选择.     

Differentiation of t(5;17) variant acute promyelocytic leukemic blasts by all-trans retinoic acid

All-trans retinoic acid (ATRA) induces differentiation of acute promyelocytic leukemic (APL) blasts from patients with t(15;17) APL. However, blasts from patients with the t(11;17) variant do not differentiate in response to ATRA. Our group has identified a variant of APL characterized by t(5;17) and expression of the NPM-RAR fusion gene product. From case reports it has been difficult to establish whether ATRA induces clinical responses in patients with this variant. In order to determine whether t(5;17) blasts differentiate with ATRA, we harvested mononuclear bone marrow cells from a patient with t(5;17) APL at time of relapse and cultured them in medium containing ATRA. Morphologic analysis of cytospins after 7 days of culture revealed that 60% of cells in the ATRA-treated culture had differentiated into mature neutrophilic forms, as opposed to less than 1% in the control culture. Seventy-three percent of cells acquired NBT positivity after exposure to ATRA, compared with 1% in the control culture. These results indicate that t(5;17) blasts retain the ability to terminally differentiate in response to retinoic acid.     

全反式维甲酸、三氧化二砷、化疗联合治疗急性早幼粒细胞白血病疗效观察

目的 评估全反式维甲酸(ATRA)、三氧化二砷(As2O3)、化疗联合治疗初诊急性早幼粒细胞白血病(APL)的疗效和患者不良反应.方法 对40例采用ATRA、As2O3、化疗三联疗法治疗的APL患者的临床资料进行回顾性分析,观察其疗效及不良反应.结果 总体CR率92.5%(37/40),完全缓解所需中位时间27(22～61)d;白细胞≥10×109/L组CR率72.7%(8/11),白细胞<10×109/L组CR率100%(29/29),差异有统计学意义(x2=8.550,P=0.004);治疗过程中无严重不良反应,仅1例发生维甲酸综合征.结论 ATRA、As2O3、化疗联合应用可作为APL患者的首选治疗方案.     

三氧化二砷联合全反式维甲酸治疗初发急性早幼粒细胞白血病的临床观察

目的 观察全反式维甲酸(ATRA)联合三氧化二砷(As2O3)治疗初诊急性早幼粒细胞白血病(APL)的疗效及不良反应.方法 对ATRA每天25mg/m2联合As2O310mg/d(联合组)治疗的35例APL患者达完全缓解(CR)时间、CR率、早期病死率及不良反应进行观察,并与单用As2O3 10 mg/d(单药组)治疗的33例进行比较.结果 联合组CR率为94.3%(33/35),与单药组[90.9%(30/33)]比较差异无统计学意义(P>0.05);联合组获得CR时间为26.1 d,短于单药组的30.5 d,差异有统计学意义(P<0.05);联合组与单药组APL分化综合征及不良反应发生率、早期病死率比较,差异均无统计学意义(均P>0.05);高WBC组比中、低WBC组CR率低,死亡率高,差异均有统计学意义(均P<0.05),低WBC组与中WBC组差异无统计学意义(P>0.05).结论 As2O3联合ATRA较单用As2O3治疗初诊APL获得CR时间短,WBC>10×109/L为预后不良的因素,APL分化综合征应尽早发现,及时处理.     

A numerical investigation into factors affecting anesthetic distribution during spinal anesthesia

Differentiation therapy for acute promyelocytic leukemia (APL) using all-trans-retinoic acid (ATRA) has improved the prognosis of the disease. ATRA therapy also causes a newly recognized clinical syndrome, the "retinoic acid syndrome" (RAS), which can be successfully managed with dexamethasone. Because aberrant function of maturing leukemic granulocytes may cause this syndrome, and because dexamethasone is useful clinically, we studied functional properties of maturing HL60 cells cultured in the presence and absence of dexamethasone. HL60 cells were cultured for 4 days with ATRA and studied daily to determine acquisition of mature neutrophil-like properties including phagocytosis, NBT reduction, actin polymerization, chemotaxis and adhesion molecule expression. Undifferentiated HL60 cells could not polymerize actin or reduce NBT, and exhibited only a minimal ability to undergo chemotaxis or ingest latex beads. Following 4 days of maturation with ATRA, the cells would increase F-actin content in response to interleukin-8, ingest latex beads, migrate in a chemotaxis chamber, reduce NBT, and express CD11b. When dexamethasone was added to the cells in culture, there was no major enhancement or suppression of these properties. We also studied the effect of dexamethasone on functional properties of normal neutrophils and found minimal if any effect on their function. Overall, these studies suggest that in vitro, dexamethasone has little effect on the function of leukemic and normal granulocytes. To further investigate the pathophysiology of the retinoic acid syndrome, future studies may need to use endothelial cells, cytokines, or granulocytes obtained from APL patients.     

All-trans-retinoic acid counteracts endothelial cell procoagulant activity induced by a human promyelocytic leukemia-derived cell line (NB4)

Therapy with all-trans-retinoic acid (ATRA) can rapidly improve the coagulopathy of acute promyelocytic leukemia (APL). This study was designed to evaluate whether the APL cell line NB4 induces the procoagulant activity (PCA) of human endothelial cells (ECs) in vitro, and whether this property is modified after ATRA-induced NB4 maturation. EC monolayers were incubated for 4 hours at 37 degrees C with the conditioned media (CM) of NB4 treated with 1 mumol/L ATRA (ATRA-NB4-CM) or the vehicle (control-NB4-CM). EC lysates were tested for PCA. ATRA-NB4-CM induced significantly more PCA:tissue factor (TF) than control-NB4-CM (P < .01). To identify the cause of TF induction, interleukin (IL)-1 beta antigen levels were measured in CM samples. ATRA-NB4-CM contained significantly more IL-1 beta than control-NB4-CM. EC PCA was significantly inhibited by an anti-IL-1 beta antibody. The addition to the media of 10 mumol/L ATRA counteracted the EC TF expression induced by NB4-CM. These data indicate that ATRA increases the promyelocyte-induced EC TF, partly through increased IL-1 beta production. However, ATRA can protect the endothelium from the procoagulant stimulus of leukemic cells.     

Effects of prostaglandin E2 and all-trans retinoic acid combination on induced differentiation of human acute promyelocytic leukemia NB4 cells

OBJECTIVE: A human promyelocytic leukemia (APL) cell line NB4 was used to demonstrate the synergistic effects between all-trans retinoic acid (ATRA) and prostaglandin E2 (PGE2) on growth inhibition and cytodifferentiation induction. METHODS: NB4 cells were cultured in the presence of either ATRA or PGE2 as a single agent or in combinations at various ratio. Cell growth was measured and myeloid differentiation was tested on consecutive days over the whole course of culture. RESULTS: PGE2 and ATRA synergistically induced the myeloid differentiation of NB4 cells. In comparison with ATRA alone, the combination of PGE2 with ATRA caused an almost 20-fold decrease of effective concentration of ATRA. CONCLUSION: The combination of ATRA and PGE2 at an appropriate ratio may provide a convenient oral regimen of combined differentiation therapy for a better clinical outcome in APL patients.