氟苯达唑对人急性髓系白血病HL-60细胞的增殖抑制作用研究

目的:研究氟苯达唑对人急性髓系白血病HL-60细胞增殖的抑制作用,明确氟苯达唑对HL-60细胞周期,凋亡发生的作用机制。方法:噻唑蓝法(MTT)检测氟苯达唑对人急性髓系白血病HL-60细胞的生长抑制作用,流式细胞术检测氟苯达唑对HL-60细胞周期,DNA片段化的影响,免疫印迹法检测Caspase, Raf, Bcl-2家族蛋白表达。结果:氟苯达唑抑制人急性髓系白血病HL-60细胞生长,HL-60细胞G2/M期增加,与阴性对照组相比,在一定的剂量和时间内,差别具有显著统计学意义;DNA片段化上升,0.25,0.5,1μM组与对照组相比差别具有显著统计学意义,促使Cleaved PARP,Cleaved-caspase 3,Cleaved-caspase 9蛋白表达量趋势增加;Bag-1和Bcl-2蛋白表达量降低;b-raf,c-raf磷酸化蛋白表达水平逐渐降低。结论:氟苯达唑通过诱导HL-60细胞阻滞于G2/M期,增加DNA片段化水平,激活Caspase, Raf, Bcl-2家族介导的凋亡相关通路抑制人急性髓系白血病HL-60细胞增殖,诱导人急性髓系白血病HL-60细胞发生凋亡而发挥抗肿瘤作用。     

New Cardenolide Glycosides from the Seeds of Digitalis purpurea and Their Cytotoxic Activity

A chemical investigation of Digitalis purpurea seeds led to the isolation of three new cardenolide glycosides (1, 8 and 11), together with 12 known cardenolide glycosides (2–7, 9, 10 and 12–15). The structures of 1, 8 and 11 were determined by 1D and 2D NMR spectroscopic analyses and the results of an acid or enzymatic hydrolysis. The cytotoxic activity of the isolated compounds (1–15) against HL-60 leukemia cells was examined. Compounds 2, 9, 11 and 12 showed potent cytotoxicity against HL-60 cells with respective 50% inhibition concentration (IC₅₀) values of 0.060, 0.069, 0.038, and 0.034 µM. Compounds 2, 9 and 11 also exhibited potent cytotoxic activity against HepG2 human liver cancer cells with respective IC₅₀ values of 0.38, 0.79, and 0.71 µM. An investigation of the structure-activity relationship showed that the cytotoxic activity was reduced by the introduction of a hydroxy group at C-16 of the digitoxigenin aglycone, methylation of the C-3' hydroxy group at the fucopyranosyl moiety, and acetylation of the C-3' hydroxy group at the digitoxopyranoyl moiety.     

Novel cytotoxic chalcones from Litsea rubescens and Litsea pedunculata

Two novel flavonoids with chalcone skeleton, together with seven known flavonoids, were isolated from the stem barks of Litsea rubescens and Litsea pedunculata. The structures of the new compounds were elucidated on the basis of spectral methods including IR, UV, 1D and 2D NMR. The new chalcones were found to contain the rare epoxy or ethylidenedioxy group. This is the first report on the presence of chalcone in the plant genus Litsea. The cytotoxic potential of two new chalcones was evaluated in vitro against three human tumor cell lines. Both new chalcones displayed potent cytotoxic activities against myeloid leukaemia (HL-60) and epidermoid carcinoma (A431) cell lines and more active than cisplatin (DDP). Interestingly, compound 1 exhibited cytotoxic activity against HL-60 with IC₅₀ value 2.1-fold more sensitive to DDP.     

Investigation on the pharmacological profile of antimony(III) complexes with hydroxyquinoline derivatives: anti-trypanosomal activity and cytotoxicity against human leukemia cell lines

Complexes [Sb(QN)₂Cl] (1), [Sb(QC)₂Cl] (2) and [Sb(QI)₂Cl] (3) were obtained with 8-hydroxyquinoline (HQN), 5-chloro-8-hydroxyquinoline (HQC) and 5-chloro-7-iodo-8-hydroxyquinoline (clioquinol, HQI). The quinoline derivatives and their antimony(III) complexes were evaluated for their anti-trypanosomal activity as well as for their cytotoxicity against HL-60 and Jurkat human leukemia cell lines. Upon coordination to antimony(III) the anti-trypanosomal activity of HQC and HQI increases, the highest improvement being observed for complex (3), which was the most active among all studied compounds against both epimastigote and trypomastigote forms of Trypanosoma cruzi. All quinoline derivatives proved to be cytotoxic against both leukemia cell lineages. Upon coordination to antimony(III) the cytotoxicity of HQN improved against Jurkat leukemia cells. While SbCl₃ proved to be cytotoxic against HL-60 cells, it was not active against Jurkat cells. However, its coordination to the quinoline derivatives resulted in complexes with significant cytotoxicity against Jurkat cells.     

A Lichen Substance as an Antiproliferative Compound against HL-60 Human Leukemia Cells: 16-O-Acetyl-leucotylic Acid Isolated from Myelochroa aurulenta

The lichen substance, 16-O-acetyl-leucotylic acid (1), was isolated from an acetone extract of Myelochroa aurulenta and found to exhibit antiproliferative activity against HL-60 human leukemia cells. This is the first report on its anti-leukemia activity (EC₅₀=21 μM) which is greater than that of leucotylic acid (2) and the structurally related anti-tumor agent, betulinic acid (4).     

Design,Synthesis, and Anti-Tumor Activity of 4′-Thionucleosides as Potent and Selective Agonists at the Human A3 Adenosine Receptor

On the basis of potent and selective binding affinity of Cl-IB-MECA to the human A₃ adenosine receptor, its 4′-thioadenosine derivatives were efficiently synthesized starting from D-gulonic γ -lactone. Among compounds tested, 2-chloro-N ⁶-(3-iodobenzyl)- and 2-chloro-N ⁶-methyl-4′ -thioadenosine-5′ -methyluronamides (7a and 7b) exhibited nanomolar range of binding affinity (K _i = 0.38 nM and 0.28 nM, respectively) at the human A₃AR. These compounds showed anti-growth effects on HL-60 leukemia cell, which resulted from the inhibition of Wnt signaling pathway.     

Retinoic Acid-Induced blr1 Expression Promotes ERK2 Activation and Cell Differentiation in HL-60 Cells

Retinoids are known to induce the differentiation and cell cycle arrest of human myeloid leukemia cells in vitro. Differential display was used to identify putative early regulatory genes that are differentially expressed in HL-60 human promyelocytic leukemia cells treated with retinoic acid. One of the cDNAs cloned encodes sequences identifying Burkitt's lymphoma receptor 1 (BLR1), a recently described chemokine receptor. Northern blot analysis demonstrates that blr1 mRNA expression increases within 9 h of retinoic acid treatment, well before functional differentiation or G₁/G₀ growth arrest at 48 h or onset of morphological changes, suggesting a possible regulatory function. The expression of blr1 mRNA is transient, peaking at 72 h when cells are differentiated. blr1 mRNA also is induced by other differentiation-inducing agents, 1α,25-dihydroxyvitamin D₃ and DMSO. Induction of blr1 mRNA by retinoic acid is not blocked by the protein synthesis inhibitor cycloheximide. In HL-60 cells stably transfected with blr1 cDNA, ectopic expression of blr1 causes an increase in ERK2 MAPK activation and promotes retinoic acid-induced G₁/G₀ growth arrest and cell differentiation. The early expression of blr1 mRNA during differentiation, its ability to increase ERK2 activation, and its enhancement of retinoic acid-induced differentiation suggest that blr1 expression may be involved in retinoic acid-induced HL-60 differentiation.     

Sodium Valproate Facilitates the Propagation of Granulocytic Ehrlichiae (Anaplasma phagocytophilum) in HL-60 Cells

As already shown, some inducers of the differentiation of promyelocytic cells along the granulocytic pathway, such as dimethylsulphoxide (DMSO) or all-trans retinoic acid, can enhance propagation of granulocytic ehrlichiae in HL-60 cell cultures. This study was conducted to prove whether sodium valproate, a salt of di-n-propylacetic acid (VPA) known to trigger cellular differentiation in several solid and hematopoietic malignancies is similarly efficient in ehrlichial cultures. Two cell lines derived from HL-60, that is, low-passage undifferentiated HL-60 (HL-60F) and high-passage HL-60 spontaneously differentiated towards monocytic phenotype (HL-60J) were grown in RPMI 1640 medium supplemented with 10% FBS. The respective HL-60F and HL-60J IC₅₀-values for NaVPA were estimated to be 0.8 and 2.2 mM under these culture conditions; to stimulate the differentiation, the respective doses of 0.3 and 1.2 mM were then applied. When the NaVPA-treated cells of both lines were challenged with an ehrlichial laboratory strain (HGE), maintained in splenectomized NMRI mice, the respective 1–2 and ≤0.1% primary infection rates in HL-60F and HL-60J cultures were observed 3 days post-inoculation. In comparison, only rare (≤0.1%) infected HL-60F and no infected HL-60J cells were recorded under the same experimental conditions in untreated control cultures. HGE continuously propagated in NaVPA-supplemented HL-60F cultures remained infectious to mice at least up to the 95th passage (12 months). NaVPA can thus facilitated continuous propagation of granulocytic ehrlichiae in cell cultures without a substantial loss of infectiveness. This revised version was published online in July 2006 with corrections to the Cover Date.     

Anti-c-myc DNA increases differentiation and decreases colony formation by HL-60 cells

Summary The proto-oncogene c-myc, whose gene product has a role in replication, is overexpressed in the human promyelocytic leukemia HL-60 cell line. Treatment of HL-60 cells with an antisense oligodeoxyribonucleotide complementary to the start codon and the next four codons of c-myc mRNA has previously been observed to inhibit c-myc protein expression and cell proliferation in a sequence-specific, dose-dependent manner. Comparable effects are seen upon treatment of HL-60 cells with dimethylsulfoxide (Me₂SO), which is also know to induce granulocytic differentiation of HL-60 cells. Hence, the effects of antisense oligomers on cellular differentiation were examine and compared with Me₂SO. Differentiation of HL-60 cells into forms with granulocytic characteristics was found to be enhanced in a sequence-specific manner by the anti-c-myc oligomer. No synergism was observed between the anti-c-myc oligomer and Me₂SO in stimulating cellular differentiation. In contrast, synergism did appear in the inhibition of cell proliferation. Finally, the anti-c-myc oligomer uniformly inhibited colony formation in semisolid medium. It is possible that further reduction in the level of c-myc expression by antisense oligomer inhibition may be sufficient to allow terminal granulocytic differentiation and reverse transformation. This work was supported by grants to E. W. from the National Institutes of Health, Bethesda, MD (CA 42960), and the Leukemia Society of America.     

Design,synthesis, in vitro antiproliferative activity and apoptosis-inducing studies of 1-(3′,4′,5′-trimethoxyphenyl)-3-(2′-alkoxycarbonylindolyl)-2-propen-1-one derivatives obtained by a molecular hybridisation approach

Inhibition of microtubule function using tubulin targeting agents has received growing attention in the last several decades. The indole scaffold has been recognized as an important scaffold in the design of novel compounds acting as antimitotic agents. Indole-based chalcones, in which one of the aryl rings was replaced by an indole, have been explored in the last few years for their anticancer potential in different cancer cell lines. Eighteen novel (3′,4′,5′-trimethoxyphenyl)-indolyl-propenone derivatives with general structure 9 were synthesized and evaluated for their antiproliferative activity against a panel of four different human cancer cell lines. The highest IC₅₀ values were obtained against the human promyelocytic leukemia HL-60 cell line. This series of chalcone derivatives was characterized by the presence of a 2-alkoxycarbonyl indole ring as the second aryl system attached at the carbonyl of the 3-position of the 1-(3′,4′,5′-trimethoxyphenyl)-2-propen-1-one framework. The structure–activity relationship (SAR) of the indole-based chalcone derivatives was investigated by varying the position of the methoxy group, by the introduction of different substituents (hydrogen, methyl, ethyl or benzyl) at the N-1 position and by the activity differences between methoxycarbonyl and ethoxycarbonyl moieties at the 2-position of the indole nucleus. The antiproliferative activity data of the novel synthesized compounds revealed that generally N-substituted indole analogues exhibited considerably reduced potency as compared with their parent N-unsubstituted counterparts, demonstrating that the presence of a hydrogen on the indole nitrogen plays a decisive role in increasing antiproliferative activity. The results also revealed that the position of the methoxy group on the indole ring is a critical determinant of biological activity. Among the synthesized derivatives, compound 9e, containing the 2-methoxycarbonyl-6-methoxy-N-1H-indole moiety exhibited the highest antiproliferative activity, with IC₅₀ values of 0.37, 0.16 and 0.17?μM against HeLa, HT29 and MCF-7 cancer cell lines, respectively, and with considerably lower activity against HL-60 cells (IC₅₀: 18?μM). This derivative also displayed cytotoxic properties (IC₅₀ values ～1?μM) in the human myeloid leukemia U-937 cell line overexpressing human Bcl-2 (U-937/Bcl-2) via cell cycle progression arrest at the G₂-M phase and induction of apoptosis. The results obtained also demonstrated that the antiproliferative activity of this molecule is related to inhibition of tubulin polymerisation. The presence of a methoxy group at the C5- or C6-position of the indole nucleus, as well as the absence of substituents at the N-1-indole position, contributed to the optimal activity of the indole-propenone-3′,4′,5′-trimethoxyphenyl scaffold.     

Derivatives of 1-(2-Deoxy-2-fluoro-β-D-arabinofuranosyl)-5-phenyluracil and 5-Benzyluracil. Synthesis and Biological Properties

Abstract

A number of 1-(2-deoxy-2-fluoro-β-D-arabinofuranosyl)uracil and -cytosine nucleosides substituted at the 5 position with a nitrophenyl or nitrobenzyl group were synthesized from 5-phenyl- and 5-benzyluracil via condensation of the fluorinated sugar, followed by nitration. The corresponding amino analogues were also prepared by reduction of the nitro nucleosides. The uracil nucleosides were converted into the corresponding cytosine nucleosides by way of the triazole intermediates. None of these nucleosides exhibited significant activity against herpes simplex virus type 1 in Vero cells. However, cytosine nucleosides containing the o-nitrophenyl, p-nitrophenyl, p-nitrobenzyl or p-aminobenzyl substituent were found to be toxic (even at 1 μM) to uninfected Vero cells, although they were essentially nontoxic in HL-60 cells. The 5′-monophosphates of the uracil nucleosides were inhibitors of the reaction catalyzed by purified Ehrlich ascites carcinoma thymidylate synthase, the 5-phenyluracil nucleotides causing a strong inhibition, competitive vs dUMP, described by the K_i value of 0.01 μM.     

Two novel neo-clerodane diterpenoids from Scutellaria barbata

Two novel neo-clerodane diterpenoids, barbatellarines A (1) and B (2), were isolated from the whole plants of Scutellaria barbata, along with the known compound scutebarbatine F (3). The chemical structures and relative stereochemistry of the isolated compounds were established by NMR (1D and 2D) and mass spectroscopic analyses. Compounds 2 and 3 were evaluated for in vitro cytotoxic activity against the HL-60 (human leukemia), MCF7 (human breast cancer), and LLC (Lewis lung carcinoma) cancer cell lines. Compound 2 exhibited weak cytotoxic activity against HL-60 cells, with an IC₅₀ value of 41.4 μΜ.     

New Steroidal Glycosides from Rhizomes of Clintonia udensis

A total of 10 steroidal glycosides, together with three new spirostanol glycosides (6–8), a new furostanol glycoside (9), and a new cholestane glycoside (10), were isolated from the rhizomes of Clintonia udensis (Liliaceae). The structures of the new compounds were determined on the basis of extensive spectroscopic analyses, including 2-D nuclear magnetic resonance (NMR) data, and of hydrolytic cleavage followed by chromatographic or spectroscopic analyses. The isolated glycosides were evaluated for their cytotoxic activity against HL-60 leukemia cells. Spirostanol glycosides 1 and 2, and furostanol glycoside 4 showed cytotoxic activity with IC₅₀ values of 3.2±0.02, 2.2±0.12, and 2.2±0.06 μg/ml, respectively. Neither the spirostanol and furostanol saponins with a hydroxy group at C-1 (6 and 9) and C-12 (7 and 8) nor cholestane glycosides (5 and 10) exhibited apparent cytotoxic activity at a sample concentration of 10 μg/ml.     

Transforming growth factor-β1 modulates the effect of 1α,25-dihydroxyvitamin D3 on leukemic cells

Summary The human leukemic cells HL-60, U937, KG-1 and THP-1 incubated with transforming growth factor-β1 (TGF-β1) were studied by examining cell surface antigens and macrophage-specific activities. The addition of 0.5 ng/ml (20 pM) of TGF-β1 with 1α,25-dihydroxyvitamin D₃ [1α, 25(OH)₂D₃] induced more Leu-M3 (CD14)-positive cells (approximately 80%) than 5×10⁻⁸ M 1α,25(OH)₂D₃ alone did (30 to 50%), although original HL-60 cells did not express any Leu-M3 antigen at all. Tumor necrosis factor-α (TNF-α) with TGF-β1 and 1α,25(OH)₂D₃ was found to potentiate the expression of these surface antigens. Furthermore, the phagocytic activity was also induced strongly. The expression of CR3 (CD11b) antigen was also increased, and all Leu-M3-positive cells were found CR3-positive when HL-60, U937, and THP-1 cells were treated with these stimulants. In contrast, CR3 but not Leu-M3 was induced in KG-1 cells after the same treatment. This may indicate that the responsiveness of leukemic cells to TGF-β1 and 1α,25(OH)₂D₃ might vary depending on a differentiation stage of the target cells. Furthermore, K562 cells originated from a more undifferentiated precursor, were not able to respond to these two inducers. These results suggested that some of TGF-β superfamily proteins might represent potent modulators in hematopoiesis, especially in the development of monocytes-macrophages or their precursors.     

IFI 16 gene encodes a nuclear protein whose expression is induced by interferons in human myeloid leukaemia cell lines

We have characterized the induction of mRNA and protein products of the human IFI 16 gene in response to IFN-γ, IFN-α, and IFN-β₂ (IL-6). We demonstrate that the IFI 16 gene product is a novel nucleoprotein expressed in association with the differentiation of myeloid precursor cell lines. In Northern blots, IFI 16 mRNA was increased ～25-fold above barely detectable levels in unstimulated promyelocytic HL-60 cells, in response to IFN-γ. Other myeloid cell lines, U937 and K562, also demonstrated a marked IFN-γ-inducibility of IFI 16 mRNA. However, all three cell lines were far less responsive to IFN-α, and there was no response to IL-6. By comparison, a panel of T and B cell lines demonstrated high constitutive expression of IFI 16 mRNA that was not regulated by these cytokines. Culture of HL-60 cells in medium containing dimethylsulfoxide, retinoic acid, and 1,25 dihydroxyvitamin D₃, agents that stimulate the differentiation of HL-60 along myeloid pathways, also caused the induction of IFI 16 mRNA. To characterize the protein product of IFI 16, a monoclonal antibody was raised against a recombinant bacterial protein comprising the amino terminal 159 amino acids of IFI 16 fused to glutathione S-transferase. The antibody, designated 1G7, was used in Western blotting to demonstrate the strong induction of a cluster of proteins of 85–95 kDa in the nuclear extracts of IFN-γ-treated HL-60. The nuclear localization of IFI 16 antigen was confirmed by immunohistochemical staining of HL-60 cells treated with IFN-γ, dimethylsulfoxide, and retinoic acid. IFI 16 was also detected in the nuclei of monocytes, neutrophils, and lymphocytes in normal peripheral blood. Database comparisons of the IFI 16 amino acid sequence revealed 51% identity with the recently cloned myeloid cell nuclear differentiation antigen (MNDA), and extensive similarity to protein products of the Gene 200 cluster of IFN-inducible genes, Ifi 202 and Ifi 204. The amino terminal domain of IFI 16 encodes a putative nuclear localization signal, ¹²⁴PGAQKRKK, which is strongly conserved in MNDA and 204. Nuclear IFI 16 was able to bind double-stranded DNA in vitro and exhibited a similar elution profile from DNA-cellulose as previously observed for MNDA and 204. Therefore, IFI 16 and MNDA are members of a novel family of human DNA-binding proteins whose expression is associated with myeloid cell differentiation induced by cytokines and chemical agents.     

Combination of diethyldithiocarbamate with 12-O-tetradecanoyl phorbol-13-acetate inhibits the growth of human myeloid leukemia HL-60 cells in vitro and in xenograft model

ABSTRACT

12-O-tetradecanoylphorbol-13-acetate (TPA), is a major active constituent of the seed oil of Croton tiglium L., has pharmacological activity for the treatment of acute myeloid leukemia patients. Diethyldithiocarbamate (DTC) is a potent inhibitor of NF-κB show activity of anticancer. In this study, we determined the effect of DTC and TPA in combination on HL-60 cells cultured in vitro and in vivo. In this study, we have shown that DTC and TPA synergistically inhibited the growth of HL-60 cells and strongly induced apoptosis in the cells. Mechanistic studies showed that the combined effects of DTC and TPA were associated with a decrease in Bcl-2. The animal experiment showed that the combination of DTC and TPA more potently inhibited the growth of HL-60 tumors than either agent alone. Our results indicate that the administration of TPA and DTC in combination may be an effective strategy for inhibiting the growth of acute myeloid leukemia cells.     

Microwave-Assisted Synthesis of 2(1H)-Pyridones and Their Glucosides as Cell Proliferation Inhibitors

A new series of substituted 2(1H)-pyridones (4a–i) and their glucosides (5, 6a–e) were prepared as potential agents against leukemia (HL-60) cells. Glucosides (5,6a–e) were synthesized using three independent methods. Microwave protocol as an ecologically new method was used to synthesize the target compounds. Structures of the new products were confirmed using one- and two-dimensional NMR spectroscopy. In vitro exposure of pyridones substituted at position 4 with a 2-thienyl or 2-(trifluoromethyl)phenyl were found to exhibit high antiproliferation activities; in particular, 3-cyano-4-(thien-2′-yl)-6-(4″-chlorophenyl)-2(1H)-pyridone (4c) and its glucoside analogue (6c) had the highest activity.     

铁皮石斛内生真菌次生代谢产物研究

为了解铁皮石斛(Dendrobium officinale)内生真菌Phyllosticta aristolochiicola的次生代谢产物,从该真菌中分离得到15个化合物,经波谱分析分别鉴定为N-methyl-2-pyrolidinone (1)、环-(甘氨酸-L-脯氨酸)(2)、环-(D-丙氨酸-L-脯氨酸)(3)、环-(L-缬氨酸-L-脯氨酸)(4)、环-(L-亮氨酸-L-脯氨酸)(5)、cyclo-(L-Leu-D-4-hydroxyprolinyl)(6)、环-(L-苯丙氨酸-L-脯氨酸)(7)、环-(L-苯丙氨酸-L-4-羟基脯氨酸)(8)、环-(L-酪氨酸-L-脯氨酸)(9)、环-(L-苯丙氨酸-L-亮氨酸)(10)、啤酒甾醇(11)、对羟基苯乙醇(12)、对羟基苯乙酸(13)、(2S,3R)-1-(4-羟基苯基)丁烷-2,3-二醇(14)和(2R,3S)-1-苯基丁烷-2,3-二醇(15)。采用MTS法检测抗肿瘤活性表明,化合物2、10和14对HL-60、A-549、SMMC-7721、MCF-7和SW-480细胞株具有一定的抑制活性。     

Effect of the structure of dietary epoxylignan on its cytotoxic activity: relationship between the structure and the activity of 7,7′-epoxylignan and the introduction of apoptosis by caspase 3/7

We compared the cytotoxic activities of dietary epoxylignans and their stereoisomers and found (?)-verrucosin, which is (7S,7′R,8R,8′R)-7,7′-epoxylignan, to be the most cytotoxic epoxylignan against HeLa cells (IC₅₀ = 6.6 μM). On the other hand, the activity was about a factor of 10 less against HL-60. In this research on the relationship between the structure and cytotoxic activity of (?)-verrucosin 13, the 7-(4-methoxyphenyl)-7′-(3,4-dimethoxyphenyl) derivative 60, for which the activity (IC₅₀ = 2.4 μM) is three times greater than (?)-verrucosin 13, was discovered. The induction of apoptosis by caspase 3/7 was observed upon treatment with the (?)-verrucosin derivative.     

CD44v6对急性白血病细胞HL-60和THP-1增殖和迁移的影响

目的:探讨CD44变异亚型对急性白血病细胞增殖和迁移的影响。方法:选择对数生长期的急性白血病细胞株HL-60、THP-1和慢性白血病细胞株K562,采用荧光定量PCR法检测CD44v6mRNA的表达。通过电转的方法转染CD44v6siRNA到HL-60和THP-1细胞抑制细胞的CD44v6表达,通过western方法检测CD44v6蛋白的抑制情况。将实验分成HL-60+N-siRNA、HL-60+CD44V6-siRNA、THP-1+N-si RNA、THP-1+CD44V6-siRNA共4组,培养24、48、72 h后分别取细胞悬液用台盼蓝染色后计数活细胞数检测细胞的增殖情况;使用Transwell小室培养法观察HL-60和THP-1细胞的迁移率。结果:通过荧光定量PCR方法检测THP-1和HL-60细胞均高表达CD44v6(分别为0.0037±0.0007和0.00292±0.0002),明显高于K562的表达(P0.01);转染后的HL-60和THP-1细胞株中CD44v6蛋白表达水平明显下调,细胞计数结果显示转染CD44v6-siRNA的HL-60和THP-1细胞在24、48和72 h增殖均明显下降。迁移实验结果显示THP-1+N-si RNA和HL-60+N-si RNA细胞的迁移率为17%和23%,与相应对照组相比THP-1+CD44v6-siRNA和HL60+CD44v6-siRNA组细胞24 h迁移率明显下降(分别降至11%和14%)。结论:CD44v6可以通过干预白血病细胞的增殖和迁移能力,参与调解白血病细胞的增殖和髓外进展。