三氧化二砷对多发性骨髓瘤细胞的影响

目的：了解多发性骨髓瘤细胞对Ａｓ２Ｏ３的反应及其可能机制。方法：使用多发性骨髓瘤细胞系ＲＰ－ＭＩ８２２６和Ｕ２６６细胞作为体外模型。细胞凋亡经细胞形态学、流式细胞仪和ＤＮＡ凝胶电泳判定通过测定细胞内荧光染料Ｒｈｏｄａｍｉｎｅ１２３的染色强度分析线粒体跨膜电位（△Ψｍ），并采用蛋白印迹分析蛋白剪切情况。结果：不同浓度的Ａｓ２Ｏ３对ＲＰＭＩ８２２６和Ｕ２２６细胞产生不同的效应：０．１～０．５ｍｏｌ／Ｌ的Ａｓ２Ｏ３抑制其增殖，２．０ｕｍｏｌ／Ｌ的Ａｓ２Ｏ３浓度的Ａｓ２Ｏ３诱导其凋亡，而１．０ｕｍｏｌ／Ｌ的Ａｓ２Ｏ３在抑制细胞增殖的同时轻度诱导细胞凋亡。Ａｓ２Ｏ３诱导的ＭＭ细胞凋亡伴随线粒体△Ψｍ下降的ｃｓａｐａｓｅ－３的活化。结论：Ａｓ２Ｏ３具有一个相对较广的诱导凋亡效应谱，而线粒体△Ψｍ破坏是Ａｓ２Ｏ３诱导细胞凋亡     

三氧化二砷诱导人类B细胞性淋巴瘤细胞凋亡及机制探讨

目的研究Ａｓ２Ｏ３在体外对人类Ｂ淋巴瘤细胞株ＭＢＣ－１细胞增殖的影响,并探讨其作用机制。方法采用细胞形态学、ＤＮＡ凝胶电泳、流式细胞术等多参数观察。结果（１）（０．５～２）ｍＭ／ＬＡｓ２Ｏ３对ＭＢＣ－１细胞有增殖抑制作用,并呈时间和剂量相关;（２）证实诱导细胞凋亡是Ａｓ２Ｏ３增殖抑制作用的主要机制之一;（３）Ａｓ２Ｏ３能够上调ＭＢＣ－１细胞ｐ５３的蛋白表达。结论Ａｓ２Ｏ３能有效地通过诱导人类Ｂ淋巴瘤细胞株ＭＢＣ－１细胞凋亡而起到增殖抑制作用,而ｐ５３基因可能参与了对该凋亡过程的调控。     

三氧化二砷诱导的结肠癌细胞凋亡及其与细胞周期的关系

目的：探讨三氧化二砷（Ａｓ２Ｏ３）对结肠癌细胞的凋亡诱导作用及其与细胞周期的关系。方法：采用透射电镜、丫啶橙荧光染色,ＴｄＴ及流式细胞仪检测药物作用前后细胞在形态学及细胞周期２等方面的变化。结果：形态学观察发现Ａｓ２Ｏ３诱导的ＬｏＶｏ细胞死亡呈现凋亡特征,研究表明随经物作用时间延长,凋亡细胞比例逐渐增加。Ａｓ２Ｏ３在低浓度时主要干扰细胞在Ｓ期的通过,高浓度时则选择性诱导Ｓ期细胞凋亡。结论：Ａｓ２ｏ     

抗氧化剂对三氧化二砷诱导HL—60细胞凋亡作用的影响

目的：探讨细胞内抗氧化剂与氧化砷（Ａｓ２Ｏ３）诱导细胞凋亡的关系。方法：采用ＨＬ－６０细胞为体外模型,采用流式细胞术观察不同抗氧化剂对氧化砷诱导细胞凋亡的影响。结果：自由基清除剂超氧化物歧化酶（ＳＯＤ）、过氧化氢酶（ＣＡＴ）、维生素Ｃ（Ｖ－Ｃ）和巯基化合物乙酰半胱氨酸（ＣＹＳ）可拮抗氧化砷诱导的细胞凋亡;砷制剂主要诱导ＨＬ－６０细胞Ｇ２－Ｍ期细胞凋亡;氧化砷对端粒酶有微弱抑制作用。结论：砷制剂与细     

三氧化二砷诱导人类B细胞性淋巴瘤细胞凋亡及机制探讨

目的 研究Ａｓ２Ｏ３在体外对人类Ｂ淋巴瘤细胞株ＭＢＣ－１细胞增殖的影响，并探讨其作用机制。方法 采用细胞形态学，ＤＮＡ凝胶电泳，流式细胞术等多参数观察。结果 （１）（０．５～２）ｍＭ／Ｌ，Ａｓ２Ｏ３对ＭＢＣ－１细胞有增殖抑制作用，并呈时间和剂量相关，（２）证实诱导细胞凋亡是Ａｓ２Ｏ３增殖抑制作用的主要机制之一；（３）Ａｓ２Ｏ３能够上调ＭＢＣ－１细胞ｐ５３的蛋白表达，结论Ａｓ２Ｏ３能有效地通过诱导人     

氧化砷对K562细胞增殖和凋亡的作用及其机制的初步研究

目的：研究氧化砷（Ａｓ２Ｏ３）对Ｋ５６２细胞增殖和凋亡的作用及其机制。方法：以细胞形态、细胞生长及活力测定,流式细胞仪分析细胞周期相关ＤＮＡ含量并以基因组ＤＮＡ电泳等方面观察Ａｓ２Ｏ３对Ｋ５６２细胞的作用,要用Ｗｅｓｔｅｒｎ印迹和Ｎｏｒｔｈｅｒｎ印迹法就其作用机制进行初步探索。结果：在Ａｓ２Ｏ３作用下Ｋ５６２细胞生长受抑伴随活力下降;基因组ＤＮＡ电泳出现”梯“状条带流式细胞仪检测出”凋亡峰“。实验进一步表明Ａｓ２Ｏ３可降低该细胞ｂｃｒ／ａｂｌ融合蛋白的含量,但不影响ＣＭＬ特异性ｂｃｒ／ａｂｌ融合基因的ｍＲＮＡ水平。结论：Ａｓ２Ｏ３有抑制Ｋ５６２细胞增殖和诱导该细胞凋亡的作用。初步研究结果表明,Ａｓ２Ｏ３导致ｂｃｒ／ａｂｌ融合蛋白降低,可能参与了作用机制。     

三氧化二砷治疗真性红细胞增多症的初步研究

目的：在观察Ａｓ２Ｏ３对Ｋ５６２细胞系和真性红细胞增多症（ＰＶ）患者外周血单个核细胞的体外效应的基础上,分析Ａｓ２Ｏ３治疗３例ＰＶ患者的临床结果。方法：以Ｋ５６２细胞和ＰＶ患者的新鲜细胞为体外靶子,通过细胞形态学,流式细胞仪和Ａｎｎｅｘｉｎ－Ｖ的测定检测细胞凋亡。每日静脉滴注１０ｍｌ０．１％Ａｓ２Ｏ３注射液治疗３例ＰＶ患者,至完全缓解停药并继续随访。结果：１￣２μｍｏｌ／Ｌ Ａｓ２Ｏ３注射液诱导Ｋ     

三氧化二砷对人胃癌细胞诱导分化的实验

目的：在三氧化二砷（Ａｓ２Ｏ３）诱导凋亡的基础上,探讨低浓度Ａｓ２Ｏ３对胃癌细胞诱导分化的作用。方法：以０．５μｍｏｌ的Ａｓ２Ｏ３处理人胃癌细胞株ＳＧＣ７９０１和ＭＫＮ４５,观察癌细胞增殖情况;经流式细胞仪检测细胞周期;用免疫组化法检测部分基因表达变化。结果：Ａｓ２Ｏ３处理后：①癌细胞增殖减缓,传至１６代后停止增殖;②４８小时后开始,Ｇ１／Ｇ０期细胞比例增加,Ｓ期细胞比例减少;③ｐ５３和ｂｃｌ－Ｘ     

常规化疗药物诱导卵巢癌OVCAR-3细胞凋亡特点的分析

目的：观察抗卵巢癌药物顺铂、紫杉醇和阿霉素对卵巢癌细胞系ＯＶＣＡＲ－３体外生长和生存的影响并分析由它们所致的细胞死亡性质。方法：采用细胞形态学观察、细胞动力学检测及ＤＮＡ片段化分析等细胞和分子生物学方法,研究化疗药物对卵巢癌细胞的凋亡诱导作用。结果：上述药物在抑制ＯＶＣＡＲ－３细胞生长的同时可不同程度地诱导细胞凋亡。其中,紫杉醇诱导细胞凋亡的能力最强;较低剂量紫杉醇（１０＾－８Ｍ）和顺铂（２μｇ／     

胰腺癌中Fas和FasL基因的表达

为探讨Ｆａｓ和ＦａｓＬ在胰腺癌组织发生细胞凋亡过程中的表达情况 ,利用胰腺癌标本和培养人胰腺癌细胞系进行了Ｆａｓ和ＦａｓＬ基因表达特征的研究以及Ｆａｓ ＦａｓＬ系统对诱导细胞凋亡的潜在作用研究。选择 14例正常胰腺标本和 16例胰腺癌标本 ,4种人胰腺癌细胞系选择ＡＳＰＣ 1、ＣＡＰＡＮ 1、ＭＩＡ ＰａＣａ 2和ＣＯＬＯ 357。采用Ｎｏｒｔｈｅｒｎｂｌｏｔ、免疫组化法测定Ｆａｓ、ＦａｓＬ基因及其蛋白产物在标本中的表达。培养细胞和组织切片上单个凋亡细胞的识别采用ＡｐｏｐＴａｇ原位细胞凋亡测定药盒完成。测定培养胰腺癌…     

Buthionine sulfoximine enhancement of arsenic trioxide-induced apoptosis in leukemia and lymphoma cells is mediated via activation of c-Jun NH2-terminal kinase and up-regulation of death receptors

The mechanism of apoptosis induced by treatment with As(2)O(3) alone or in combination with buthionine sulfoximine (BSO) was studied in NB4, U937, Namalwa, and Jurkat cells. As(2)O(3) at concentrations <2 micromol/L induced apoptosis in NB4 cells and Namalwa cells but not in U937 and Jurkat cells. As(2)O(3)-induced apoptosis in NB4 cells and Namalwa cells correlated with increase of H(2)O(2) and caspase activation without activation of c-Jun NH(2)-terminal kinase (JNK). BSO (10 micromol/L) depleted the reduced form of intracellular glutathione without inducing apoptosis but synergized with 1 micromol/L As(2)O(3) to induce apoptosis in all four cell lines. This synergy correlated with JNK activation. Treatment with As(2)O(3) plus BSO, but not with As(2)O(3) alone, increased the levels of death receptor (DR) 5 protein and caspase-8 cleavage. The JNK inhibitor SP600125 inhibited the increase in DR5 protein and attenuated apoptosis induced by treatment with As(2)O(3) plus BSO. These observations suggest that a DR-mediated pathway activated by JNK is involved in apoptosis induced by treatment with As(2)O(3) plus BSO.     

三氧化二砷诱导骨髓瘤细胞凋亡机制研究

目的 了解三氧化二砷（As2O3)诱导多发性骨髓瘤细胞（MM）凋亡的可能机制及其与维甲酸和干扰素的相互作用。方法 联合应用As2O3和巯基还原剂（DTT）、谷胱甘肽耗褐剂（BSO）、全反式维甲酸（ATRA）或干扰素（ＩＦＮ－α）处理MM细胞系RPM18226和U266细胞;应用台盼蓝拒染法计数细胞活力,经细胞形态学和流式细胞仪等判定细胞凋亡的程度;通过测定细胞内荧光染料Rhodamine123的色强度分析线粒体跨膜电位（△ψm)。结果 BSO可加强As2O3诱导的RPM18226和U266细胞线粒体△ψm下降和凋亡,而DTT则有部分拮抗的作用,ATRA诱导RPMI8226细胞闻过则喜亡,但它和As2O3之间无协同效尖,ATRA并不诱导U266细胞凋亡。此外,INF-α,既不抑制RPMIS226和U266细胞的生长和活力,也不改变As2O3对这些细胞的作用。结论 As2O3诱导多发性骨髓瘤细胞凋亡和巯基有关,但ATRA干扰素和As2O3无协同效应。     

Apoptosis and growth inhibition in malignant lymphocytes after treatment with arsenic trioxide at clinically achievable concentrations.

BACKGROUND: Arsenic trioxide (As2O3) can induce clinical remission in patients with acute promyelocytic leukemia via induction of differentiation and programmed cell death (apoptosis). We investigated the effects of As2O3 on a panel of malignant lymphocytes to determine whether growth-inhibitory and apoptotic effects of As2O3 can be observed in these cells at clinically achievable concentrations. METHODS: Eight malignant lymphocytic cell lines and primary cultures of lymphocytic leukemia and lymphoma cells were treated with As2O3, with or without dithiothreitol (DTT) or buthionine sulfoximine (BSO) (an inhibitor of glutathione synthesis). Apoptosis was assessed by cell morphology, flow cytometry, annexin V protein level, and terminal deoxynucleotidyl transferase labeling of DNA fragments. Cellular proliferation was determined by 5-bromo-2'-deoxyuridine incorporation into DNA and flow cytometry and by use of a mitotic arrest assay. Mitochondrial transmembrane potential (delta psi(m)) was measured by means of rhodamine 123 staining and flow cytometry. Protein expression was assessed by western blot analysis or immunofluorescence. RESULTS: Therapeutic concentrations of As2O3 (1-2 microM) had dual effects on malignant lymphocytes: 1) inhibition of growth through adenosine triphosphate (ATP) depletion and prolongation of cell cycle time and 2) induction of apoptosis. As2O3-induced apoptosis was preceded by delta psi(m) collapse. DTT antagonized and BSO enhanced As2O3-induced ATP depletion, delta psi(m) collapse, and apoptosis. Caspase-3 activation, usually resulting from delta psi(m) collapse, was not always associated with As2O3-induced apoptosis. As2O3 induced PML (promyelocytic leukemia) protein degradation but did not modulate expression of cell cycle-related proteins, including c-myc, retinoblastoma protein, cyclin-dependent kinase 4, cyclin D1, and p53, or expression of differentiation-related antigens. CONCLUSIONS: Substantial growth inhibition and apoptosis without evidence of differentiation were induced in most malignant lymphocytic cells treated with 1-2 microM As2O3. As2O3 may prove useful in the treatment of malignant lymphoproliferative disorders.     

Arsenic trioxide-induced apoptosis and differentiation are associated respectively with mitochondrial transmembrane potential collapse and retinoic acid signaling pathways in acute promyelocytic leukemia.

Recent studies showed that arsenic trioxide (As2O3) could induce apoptosis and partial differentiation of leukemic promyelocytes. Here, we addressed the possible mechanisms underlying these two different effects. 1.0 microM As2O3-induced apoptosis was associated with condensation of the mitochondrial matrix, disruption of mitochondrial transmembrane potentials (DeltaPsim) and activation of caspase-3 in acute promyelocytic leukemia (APL) cells regardless of their sensitivity to all-trans retinoic acid (ATRA). All these effects were inhibited by dithiothreitol (DTT) and enhanced by buthionine sulfoximine (BSO). Furthermore, BSO could also render HL60 and U937 cells, which had the higher cellular catalase activity, sensitive to As2O3-induced apoptosis. Surprisingly, 1.0 microM As2O3 did not induce the DeltaPsim collapse and apoptosis, while 0.1 microM As2O3 induced partial differentiation of fresh BM cells from a de novo APL patient. In this study, we also showed that 0.2 mM DTT did not block low-dose As2O3-induced NB4 cell differentiation, and 0. 10.5 microM As2O3 did not induce differentiation of ATRA-resistant NB4-derived sublines, which were confirmed by cytomorphology, expression of CD11b, CD33 and CD14 as well as NBT reduction. Another interesting finding was that 0.10.5 microM As2O3 could also induce differentiation-related changes in ATRA-sensitive HL60 cells. However, the differentiation-inducing effect could not be seen in ATRA-resistant HL60 sublines with RARalpha mutation. Moreover, low-dose As2O3 and ATRA yielded similar gene expression profiles in APL cells. These results encouraged us to hypothesize that As2O3 induces APL cell differentiation through direct or indirect activation of retinoic acid receptor-related signaling pathway(s), while DeltaPsim collapse is the common mechanism of As2O3-induced apoptosis.     

血液肿瘤细胞对氧化砷的敏感性与其抗氧化能力的关系

目的　探讨血液肿瘤细胞对三氧化二砷 (As2 O3 )的敏感性和细胞抗氧化能力的关系。方法　应用 9个血液肿瘤细胞系 ,通过细胞活力、形态学和流式细胞仪检测细胞凋亡 ,并测定细胞系的谷胱甘肽 (GSH)含量和 4种抗氧化酶的活性。结果　除了HL 6 0、U937、K5 6 2和Jurkat细胞外 ,其他5个细胞对As2 O3 诱导的凋亡敏感。与敏感细胞系比较 ,As2 O3 耐受细胞系存在较高的GSH含量和(或 )过氧化氢酶活性。谷胱甘肽过氧化物酶、谷胱甘肽S转移酶和超氧化物歧化酶活性与细胞对As2 O3 诱导凋亡效应敏感性无明显相关。结论　细胞内GSH水平和过氧化氢酶的活性是决定血液肿瘤细胞对As2 O3 敏感性的重要因素。     

Antagonism of buthionine sulfoximine cytotoxicity for human neuroblastoma cell lines by hypoxia is reversed by the bioreductive agent tirapazamine

Relapse of neuroblastoma (NB) commonly occurs in hypoxic tissues. Buthionine sulfoximine (BSO), an inhibitor of glutathione (GSH) synthesis, is cytotoxic for NB cell lines in atmospheric oxygen (20% O(2)). Tirapazamine (TPZ) is a bioreductive agent that forms a toxic-free radical in hypoxia. We determined in four NB cell lines cytotoxicity using the DIMSCAN digital imaging fluorescence assay, glutathione (GSH) levels by the DTNB-GSSG reductase method, apoptosis, reactive oxygen species (ROS), and mitochondrial membrane potential (Delta psi(m)) by flow cytometry. Hypoxia (2% O(2)) antagonized BSO-mediated ROS, apoptosis, and cytotoxicity but not GSH depletion. TPZ synergistically enhanced BSO cytotoxicity in hypoxia for all four NB cell lines, achieving 2-4 logs of cell kill. BSO depleted GSH (8-42% of controls) in 20 and 2% O(2), whereas TPZ only decreased GSH in hypoxia. Maximal GSH depletion was induced by BSO + TPZ. N-acetylcysteine abrogated GSH depletion caused by TPZ but not by BSO. BSO increased ROS, decreased Delta psi(m), and caused apoptosis in 20% O(2) (but not in 2% O(2)). TPZ elevated ROS in 2% O(2) (but not in 20% O(2)), whereas BSO + TPZ increased ROS both in 20 and 2% O(2). In hypoxia, TPZ alone or TPZ + BSO caused an 80% decrease of Delta psi(m) at 24 h, preceding apoptosis in 74-86% of cells at 48 h. Thus, hypoxia significantly antagonizes BSO-mediated cytotoxicity for NB cell lines, but TPZ reversed the inhibition of BSO-mediated cytotoxicity in hypoxia, causing increased ROS, Delta psi(m) decrease, GSH depletion, apoptosis, and synergistic cytotoxicity. These data additionally define the role of ROS in BSO-mediated cytotoxicity and suggest that combining BSO with TPZ could have clinical activity against NB in hypoxic sites.     

Involvement of CD95-independent caspase 8 activation in arsenic trioxide-induced apoptosis.

Arsenic trioxide (As2O3)-treatment is effective in acute promyelocytic leukemia (APL) patients with t(15;17). Clinically achievable concentrations of As2O3 induce apoptosis in NB4, an APL cell line, in vitro. Here, to study the mechanism of As2O3-induced apoptosis, we established an As2O3-resistant subline, NB4/As. Growth of NB4/As was inhibited by 50% after 2 day-treatment (IC50) at 1.6 microM As2O3, whereas IC50 of NB4 was 0.3 microM. Degradation of PML-RARalpha and change of the PML-subcellular localization were similarly induced by As2O3 in NB4 and NB4/As, suggesting that their contribution to apoptosis is small. Treatment with 1 microM As2O3 induced the activation of caspase 3 as well as a loss of mitochondrial transmembrane potential (deltapsim) in NB4 but not in NB4/As. Caspase 8 and Bid were also activated by As2O3 in NB4 but not in NB4/As. In NB4, an inhibitor of caspase 8 blocked not only the activation of caspase 3 but also the loss of deltapsim. Neither cell line expressed CD95/Fas, and agonistic anti-Fas antibody (CH-11) failed to cause apoptosis. Neither antagonistic anti-CD95/Fas antibody nor anti-Fas ligand antibodies influenced the As2O3-induced apoptosis. NB4/As had a higher concentration of intracellular glutathione (GSH) than NB4 (96 vs 32 nmol/mg). Reduction of the GSH level by buthionine sulfoxide (BSO) completely restored the sensitivity to As2O3 in NB4/As. Furthermore, caspase activation and the loss of deltapsim were recovered by combination treatment with BSO. These findings suggest that the As2O3 treatment activates caspase 8 in a CD95-independent but GSH concentration-dependent manner. In combination with BSO, As2O3 might be applied to therapy of leukemia/cancers which are insensitive to the clinically achievable concentrations of As2O3.     

Arsenic trioxide-induced mitotic arrest and apoptosis in acute promyelocytic leukemia cells.

Arsenic trioxide (As(2)O(3)), an effective drug for the treatment of acute promyelocytic leukemia (APL), can induce apoptosis and partial differentiation in APL cells in vitro and in vivo. However, As(2)O(3) also induces apoptosis in cancer cells other than APL with complex mechanisms, which seem to be cell type dependent. In this study, we report that APL cells (NB4 cell line) are arrested at early mitotic phase before the collapse of mitochondrial transmembrane potential (Deltavarphi(m)) and apoptosis after treatment with pharmacological concentrations (1.0-2.0 micro M) of As(2)O(3). We have also made the following new discoveries: (1) 0.5 micro M As(2)O(3) that fails to induce apoptosis has no effects on cell cycle distribution. (2) With inhibition of As(2)O(3)-induced Deltavarphi(m) collapse and apoptosis, dithiothreitol also effectively inhibits As(2)O(3)-induced mitotic arrest, suggesting that both As(2)O(3)-induced apoptosis and mitotic arrest involve proteins with thiol groups. (3) 1.5 mM caffeine that relieves cells from G(2)/M arrest also inhibits As(2)O(3)-induced Deltavarphi(m) collapse and apoptosis, (4) 1.0 micro M As(2)O(3) increases the expression of both cyclin B(1) and hCDC20 whereas it inhibits Tyr15 phosphorylation of p34(cdc2). In conclusion, our results strongly support that there is a tight link between As(2)O(3)-induced apoptosis and mitotic arrest, the latter being one of common mechanisms for As(2)O(3)-induced apoptosis in cancer cells.     

Apoptotic effect of oridonin on NB4 cells and its mechanism

The anti-proliferation effects of oridonin on acute promyelocytic leukemia (APL) cells and its mechanisms were studied in vitro. NB4 cells as well as fresh leukemia cells obtained from APL patients in culture medium were treated with different concentrations of oridonin. Cell growth inhibition, apoptosis and related pathways were assessed by MTT assay as well as flow cytometry (FCM) and western blot analysis. The data revealed that oridonin (over 16 micromol/L) could inhibit the growth of NB4 cells by induction of apoptosis. Marked changes of cell apoptosis were observed very clearly by using electron microscopy and DNA fragmentation analysis after the cells exposed to oridonin for 48 h; Western blotting showed cleavage of the caspase-3 zymogen protein (32-kDa) with the appearance of its 20-kDa subunit as well as a cleaved 89-kDa fragment of 116-kDa PARP when apoptosis occurred. The expression of Bcl-2 was down-regulated remarkably accompanied by the disruption of the mitochondrial membrane potential (delta(psi)m). The anti-proliferative and apoptosis-inducing effects by oridonin in fresh APL cells were also found remarkably using Trypan Blue dye exclusion method and Wright's staining. We concluded that oridoning has significant anti-proliferative and apoptosis-inducing effects on NB4 cells by activation of caspase-3 and cleavage of PARP as well as by down regulation of Bcl-2 and disruption of the delta(psi)m. Furthermore, oridonin demonstrated apparent cell growth inhibition effects on fresh APL cells in vitro. The results indicated that oridonin may serve as a potential anti-leukemia reagent.     

低剂量氧化砷治疗早幼粒细胞白血病的实验研究

背景与目的：低剂量三氧化二砷（arsenic trioxide,As2O3）是治疗急性早幼粒细胞性白血病（APL）的有效手段之一,它不仅对初发APL病人有效,而且对全反式维甲酸（ATRA）巳耐受的复发APL病人可获得完全缓解。然而,目前其诱导APL缓解的机制尚不清楚。为此,本研究试图探低剂量As2O3治疗APL的可能机制。方法：以APL细胞株NB4和来源于APL患者骨髓的原代细胞为模型。通过观察细胞形态、对四氮唑蓝的还原能力和细胞表面分化抗原的变化来鉴定细胞分化;并应用免疫荧光和Western blot分析细胞内PML-RARα融合蛋白的变化。结果：0.25μmol/L AS2O3联合环腺苷酸（cAMP）拟似物8-对氯苯硫基环腺苷酸（8-CPT-CAMP）可诱导NB4细胞和原代细胞分化,而且该效应能被蛋白激酶PKA的抑制剂H89抑制。进一步研究还显示8-CPT-CAMP可以促进AS2O3介导的PML-RARα融合蛋白降解。结论：cAMP可增强AS2O3对APL细胞的分化诱导效应。