The expression of three protooncogenes (c-myc, c-fos, N-ras) in.the primary cells from 53 cases of leukemia as well as peripheral WBC from 8 normal individuals was studied. Semiquantitative analysis of mRNA levels of ...The expression of three protooncogenes (c-myc, c-fos, N-ras) in.the primary cells from 53 cases of leukemia as well as peripheral WBC from 8 normal individuals was studied. Semiquantitative analysis of mRNA levels of the protooncogenes was carried out by Quick-blot. The results showed that (1) c-myc oncogene was slightly expressed and Nras was marginally expressed, whereas the expression of the c-fos was undetectable in the peripheral leucocytes of 8 normal individuals; (2) the c-myc was obviously expressed in almost all leukemic cells irrespective of the cell types, while N-ras and c-fos were variable expressed; (3) the c-fos was expressed in all 4 cases of M4; (4) the c-myc transcript was detected but the N-ras and c-fos were not in 4 chronic leukemic cases; (5) the relationship between protooncogene expression and state of leukemia or after chemotherapy was also analysed.展开更多
In the present work,we present the use of gold nanorods as plasmonic nanoparticles for selective photothermal therapy of human acute(HL-60)and chronicle(K-562)leukemia cells using a near-infrared laser.We improved a p...In the present work,we present the use of gold nanorods as plasmonic nanoparticles for selective photothermal therapy of human acute(HL-60)and chronicle(K-562)leukemia cells using a near-infrared laser.We improved a published methodology of gold nanorods conjugation to generate high yields of narrow band gold nanorods with an optical absorption centered at 760 nm.The manufactured nanorods were pegylated and conjugated with monoclonal antibody to become non-toxic as biocompatible nanothermolysis agent.Gold nanorods are synthesized and conjugated to CD33 monoclonal antibody.After pegylation,or conjugation with CD33 antibody,gold nanorods were non-toxic to acute and chronic leukemia cells.Our modified gold nanorod CD33 conjugates shown high level of accumulation for both leukemia cell lines,and successful used for nanothermolysis of human leukemia cells in vitro.Each sample was illuminated with 1 or 3 laser shots as for low and for high laser fluence.The radiation was provided by a Quanta Systems q-switched titanium sapphire laser,and the system was designed for maximum sample coverage using non-focused illumination.HL-60 and K-562 cells were treated for 45 min with gold nanorods CD33 conjugated,or with pegylated gold nanorods.The effect of pulsed-laser nanothermolysis for acute and chronic leukemia cells were investigated with cell counting for number of living cells,percentage of cell death and functional parameters such as damage of cell membrane and metabolic activity.Gold nanorods CD33 conjugates significantly increase cell damage for low fluence laser and completely destroyed cancer cells after 3 pulses for low fluence(acute leukemia)and for high fluence laser as for HL-60(acute)and for K-562(chronicle)leukemia cells.展开更多
I-labelled anti-thymoglobuline (ATG), 131 I-labelled immunoconjugate ATG-Dex-DNR and 131 I-labelled Ts-MoAb as control antibody, respectively.were injected by intraperitoneal (i. p.) administration into nude mice used...I-labelled anti-thymoglobuline (ATG), 131 I-labelled immunoconjugate ATG-Dex-DNR and 131 I-labelled Ts-MoAb as control antibody, respectively.were injected by intraperitoneal (i. p.) administration into nude mice used as models for human T-cell leukemia. SPECT imaging was performed from day 1 to day 8 following i. p. injection. The results showed that radioimmunoimaging of buman tumor xenografts was clearest day 3 after injection in both of ATG and ATG-Dex-DNR groups, whereas it's not the case in Ts-MoAb group. Nude mice were killed 8th day after injection with antibody or conjugate. The tumor, as well as different dissected normal organs including heart, liver, lungs, kidney, femur and intestine, were harvested, weighed precisely, and radioiodine-counted. T/NT ratios in experimental group was greater than 1. 0 (ranged from 1. 246-7. 865). and in control group they were less than 1. 0 (ranged from 0. 263-0. 757, except for tumor/femur ratio). Our results indicated that ATG and ATG-Dex-DNR had specific affinity to cell line of Tcell leukemia CEM.展开更多
Using Southern blot, Northern blot and Quick blot methods, we examined the rearrangement and expression of TCR βgene in four early differentiation stage cell lines from human hemopoietic system, namely HL-60, Jurkat,...Using Southern blot, Northern blot and Quick blot methods, we examined the rearrangement and expression of TCR βgene in four early differentiation stage cell lines from human hemopoietic system, namely HL-60, Jurkat, Daudi and Raji cells as well as lymphocytes from 17 acute lymphocytic leukemia (ALL) patients. The results showed. Ⅰ) Rearrangement of TCR βgene was seen in Jurkat cells. A germline pattern was observed in HL-60, Daudi and Raji cells. 2) Eight of 9 patients with T-ALL had cells with rearranged TCR βgene. But two of 3 patients with B-ALL and three of 5 patients with nonT, nonB-ALL also had cells with rearranged TCR βgene. 3) A 1.3 kb full-length transcript and a 1.0 kb truncated transcript were detected in Jurkat cells by probing with <sup>32</sup>P-TCR βcDNA. But some leukemic B cells also expressed an incompleted transcript. 4) TCR βmRNA was detected in six of 8 patients with T-ALL, four of 5 patients with nonT, nonB-ALL and one of 3 patients with B-ALL. But the level of expression was quite differ ent. The dual-rearrangement and the abnormal expression may give us a new clue for researching leukemogenesis.展开更多
Background: Human organic cationic transporter1 (Hoct1) is a plasma membrane transporter responsible for the main influx of Imatinib into chronic myeloid leukemia (CML) cells. Single nucleotide polymorphisms (SNPs) in...Background: Human organic cationic transporter1 (Hoct1) is a plasma membrane transporter responsible for the main influx of Imatinib into chronic myeloid leukemia (CML) cells. Single nucleotide polymorphisms (SNPs) in the gene coding for hOCT1 are important factors causing Imatinib resistance. We investigated the frequency of hOCT1 SNP C480G among Egyptian CML patients and its relation to early molecular response as an indicator of treatment outcome. Materials and Methods: Two groups of CML patients were included in this study. Group I consisted of 25 patients responding to Imatinib treatment (Imatinib responsive) and group II consisted of 25 patients resistant to Imatinib (Imatinib resistant). Response criteria were assessed according to the NCCN (National Comprehensive Cancer Network) guidelines 2017. Twenty healthy controls of matched age and sex were also included (group III). For all patients, we studied hOCT1 C480G at initial presentation using Taqman drug metabolism genotyping as well as BCR-ABL percent at diagnosis and after 3 months interval. Results: hOCT1 C480G was present in 32% of studied CML patients. CC (wild) was detected in 68% of group I and 64% of group II. CG (mutant heterozygous) was present in 28% of group I and 36% of group II while GG (mutant homozygous) was detected in only one case in group I. CG was also detected in 15% of control subjects There was no significant difference between hOCT1 C480G polymorphism and Early Molecular Response (χ2 = 0.089, p = 0.765). Conclusions: hOCT1 C480G polymorphism has no association with Imatinib resistance in Egyptian population. However, further studies on a larger number of patients are still needed to confirm this finding.展开更多
OBJECTIVE: To probe insights into the reversal effect of bufalin on vincristine-acquired multidrug resistance(MDR) in human leukemia cell line K562/VCR.METHODS: Proliferative inhibition rate and the reversal index(RI)...OBJECTIVE: To probe insights into the reversal effect of bufalin on vincristine-acquired multidrug resistance(MDR) in human leukemia cell line K562/VCR.METHODS: Proliferative inhibition rate and the reversal index(RI) of bufalin were determined by Methyl thiazolyl tetrazolium assay. The uptake of Adriamycin(ADM) in K562/VCR cells, cell cycle and apoptosis rate were determined by flow cytometry(FCM). Cell morphologic changes were observed with Wright-Giemsa staining. The expression of P-glycoprotein(P-gp), multidrug-associated protein-1(MRP1), Bcl-x L and Bax protein were measured by immunocytochemistry.RESULTS: The human leukemia multidrug resistant K562/VCR cells showed no cross-resistance to bufalin. The RIs of bufalin at concentrations of 0.0002,0.001 and 0.005 μmol/L were 4.85, 6.94 and 14.77,respectively. Preincubation of 0.001 μmol/L bufalin for 2 h could increase intracellular ADM fluorescence intensity to 28.07%(P<0.05) and down-regulate MRP1 expression simultaneously, but no remarkable effect was found on P-gp protein. Cell cycle analysis indicated increased apoptosis rate and apparent decreased G2/M phase proportion after treatment with bufalin. When exposed to 0.01μmol/L bufalin, typical morphological changes of apoptosis could be observed. Down-regulation of Bcl-x L and up-regulation of Bax expression in K562/VCR cells could be detected by immunocytochemistry.CONCLUSION: Bufalin could partly reverse the MDR of K562/VCR cells, with a possible mechanism of down-regulating MRP1 expression and activating apoptosis pathway by altering Bcl-x L/Bax ratio.展开更多
To investigate the potential effects of pure total flavonoid compounds(PTFCs) from Citrus paradisi Macfadyen separately or combined with arsenic trioxide on the proliferation of human myeloid leukemia cells and the ...To investigate the potential effects of pure total flavonoid compounds(PTFCs) from Citrus paradisi Macfadyen separately or combined with arsenic trioxide on the proliferation of human myeloid leukemia cells and the mechanisms underlying the action of PTFCs. The effects of PTFCs separately or combined with arsenic trioxide on the proliferation and apoptosis of leukemia cells were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT), fluorescence microscopy, and flow cytometry. Their effects on the expression levels of apoptosisrelated regulators were determined by Western blot assay. PTFCs combined with arsenic trioxide significantly inhibited the growth of Kasumi-1 cells, and apoptosis was confirmed by flow cytometry analysis. Hoechst 33258 staining showed more significant morphological changes and more apoptosis following the combined treatment. Western blots showed changes in the expression of genes for poly ADP-ribose polymerase(PARP), caspase 3/9, and P65. The results indicated that PTFCs separately or combined with arsenic trioxide inhibited proliferation of leukemia cells in vitro and induced their apoptosis by modulating the expression of apoptosis-related regulator genes.展开更多
Imatinib,a breakpoint cluster region(BCR)-Abelson murine leukemia(ABL) tyrosine kinase inhibitor(TKI),has revolutionized the treatment of chronic myelogenous leukemia(CML).However,development of multidrug resistance(M...Imatinib,a breakpoint cluster region(BCR)-Abelson murine leukemia(ABL) tyrosine kinase inhibitor(TKI),has revolutionized the treatment of chronic myelogenous leukemia(CML).However,development of multidrug resistance(MDR) limits the use of imatinib.In the present study,we aimed to investigate the mechanisms of cellular resistance to imatinib in CML.Therefore,we established an imatinib-resistant human CML cell line(K562-imatinib) through a stepwise selection process.While characterizing the phenotype of these cells,we found that K562-imatinib cells were 124.6-fold more resistant to imatinib than parental K562 cells.In addition,these cells were cross-resistant to second-and third-generation BCR-ABL TKIs.Western blot analysis and reverse transcription-polymerase chain reaction(RT-PCR) demonstrated that P-glycoprotein(P-gp) and MDR1 mRNA levels were increased in K562-imatinib cells.In addition,accumulation of [14C]6-mercaptopurine(6-MP) was decreased,whereas the ATP-dependent efflux of [14C]6-MP and [3H]methotrexate transport were increased in K562-imatinib cells.These data suggest that the overexpression of P-gp may play a crucial role in acquired resistance to imatinib in CML K562-imatinib cells.展开更多
Peripheral blood mononuclear cells(PBMNC)isolated from patients with acuteleukemia(AL)and from normal controls were cultured in a medium containing1000units/ml of recombinant interleukin-2(IL-2).Marked LAK activ...Peripheral blood mononuclear cells(PBMNC)isolated from patients with acuteleukemia(AL)and from normal controls were cultured in a medium containing1000units/ml of recombinant interleukin-2(IL-2).Marked LAK activity was induced onthe third culture day in the normal controls,with the highest cytotoxicity appearing be-tween day 3 and 5,whereas induction of LAK activity in the AL patients began on the5th day of culture,with a peak level appearing at day 15,showing that the peak ofLAK activity was significantly delayed in AL.LAK cells surface phenotyping tests showedthat CD<sub>8</sub> and CD<sub>16</sub> positive cells began to increase significantly from day 5 and reachedthe highest level at week 3,whereas CD<sub>4</sub><sup>-</sup> subclass began to decrease at day 5 anddropped to the nadir at week 3,indicating that LAK activity was positively correlatedwith the proportion of CD<sub>8</sub><sup>+</sup> and CD<sub>16</sub><sup>+</sup> cells,but negatively with that of CD<sub>4</sub><sup>+</sup> cells.展开更多
Adult T-cell leukemia( ATL) is a mature T-cell malignancy caused by human T-cell leukemia virus type I infection, and 10%-25% of patients show central nervous system( CNS) involvement. CNS involvement significantly re...Adult T-cell leukemia( ATL) is a mature T-cell malignancy caused by human T-cell leukemia virus type I infection, and 10%-25% of patients show central nervous system( CNS) involvement. CNS involvement significantly reduces survival and there are no effective treatments for CNS involvement. Therefore, an appropriate animal model is required to evaluate the inhibitory effects of novel drugs on the progression of ATL with CNS involvement. Here, we established a mouse model of ATL with CNS involvement using NOD.Cg-Prkdc~ (scid) Il2 rg ^(tm1Wjl)/SzJ mice inoculated with ATL cells intramuscularly in the postauricular region, and these mice showed paraparesis. Of the 10 mice inoculated with ATL cells intramuscularly(I.M.) at 5 weeks of age, 8(80%) showed paraparesis, whereas none of the 10 mice inoculated with ATL cells subcutaneously(S.C.) showed paraparesis. In the I.M. group, PCR detected HTLV-1-specific genes in the thoracic and lumbar vertebrae; however, in the S.C. group, the vertebrae were negative for HTLV-1 genes. Histological analysis revealed a particularly high incidence of tumors, characterized by accumulation of the injected cells, in the thoracic vertebrae of mice in the I.M. group. Tumor cell infiltration was relatively high in the bone marrow. Spinal cord compression caused by invasion of the tumor mass outside the pia mater was observed in the thoracic vertebrae of the spinal cord. In conclusion, we have reported a mouse model of tumor growth with paraparesis that may be used to assess novel therapeutic agents for ATL with CNS involvement.展开更多
Our previous study demonstrated that human KIAA0100 gene was a novel acute monocytic leukemia-associated antigen (MLAA) gene. But the functional characterization of human KIAA0100 gene has remained unknown to date. He...Our previous study demonstrated that human KIAA0100 gene was a novel acute monocytic leukemia-associated antigen (MLAA) gene. But the functional characterization of human KIAA0100 gene has remained unknown to date. Here, firstly, bioinformatic prediction of human KIAA0100 gene was carried out using online softwares; Secondly, Human KIAA0100 gene expression was downregulated by the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) 9 system in U937 cells. Cell proliferation and apoptosis were next evaluated in KIAA0100-knockdown U937 cells. The bioinformatic prediction showed that human KIAA0100 gene was located on 17q11.2, and human KIAA0100 protein was located in the secretory pathway. Besides, human KIAA0100 protein contained a signalpeptide, a transmembrane region, three types of secondary structures (alpha helix, extended strand, and random coil) , and four domains from mitochondrial protein 27 (FMP27). The observation on functional characterization of human KIAA0100 gene revealed that its downregulation inhibited cell proliferation, and promoted cell apoptosis in U937 cells. To summarize, these results suggest human KIAA0100 gene possibly comes within mitochondrial genome; moreover, it is a novel anti-apoptotic factor related to carcinogenesis or progression in acute monocytic leukemia, and may be a potential target for immunotherapy against acute monocytic leukemia.展开更多
文摘The expression of three protooncogenes (c-myc, c-fos, N-ras) in.the primary cells from 53 cases of leukemia as well as peripheral WBC from 8 normal individuals was studied. Semiquantitative analysis of mRNA levels of the protooncogenes was carried out by Quick-blot. The results showed that (1) c-myc oncogene was slightly expressed and Nras was marginally expressed, whereas the expression of the c-fos was undetectable in the peripheral leucocytes of 8 normal individuals; (2) the c-myc was obviously expressed in almost all leukemic cells irrespective of the cell types, while N-ras and c-fos were variable expressed; (3) the c-fos was expressed in all 4 cases of M4; (4) the c-myc transcript was detected but the N-ras and c-fos were not in 4 chronic leukemic cases; (5) the relationship between protooncogene expression and state of leukemia or after chemotherapy was also analysed.
基金supported by the NIH(Grants R44 CA110137-05R44 CA110137-05S1)SBIR Grant from the National Institute of Environmental Health Sciences(1R43ES021629-01)。
文摘In the present work,we present the use of gold nanorods as plasmonic nanoparticles for selective photothermal therapy of human acute(HL-60)and chronicle(K-562)leukemia cells using a near-infrared laser.We improved a published methodology of gold nanorods conjugation to generate high yields of narrow band gold nanorods with an optical absorption centered at 760 nm.The manufactured nanorods were pegylated and conjugated with monoclonal antibody to become non-toxic as biocompatible nanothermolysis agent.Gold nanorods are synthesized and conjugated to CD33 monoclonal antibody.After pegylation,or conjugation with CD33 antibody,gold nanorods were non-toxic to acute and chronic leukemia cells.Our modified gold nanorod CD33 conjugates shown high level of accumulation for both leukemia cell lines,and successful used for nanothermolysis of human leukemia cells in vitro.Each sample was illuminated with 1 or 3 laser shots as for low and for high laser fluence.The radiation was provided by a Quanta Systems q-switched titanium sapphire laser,and the system was designed for maximum sample coverage using non-focused illumination.HL-60 and K-562 cells were treated for 45 min with gold nanorods CD33 conjugated,or with pegylated gold nanorods.The effect of pulsed-laser nanothermolysis for acute and chronic leukemia cells were investigated with cell counting for number of living cells,percentage of cell death and functional parameters such as damage of cell membrane and metabolic activity.Gold nanorods CD33 conjugates significantly increase cell damage for low fluence laser and completely destroyed cancer cells after 3 pulses for low fluence(acute leukemia)and for high fluence laser as for HL-60(acute)and for K-562(chronicle)leukemia cells.
文摘I-labelled anti-thymoglobuline (ATG), 131 I-labelled immunoconjugate ATG-Dex-DNR and 131 I-labelled Ts-MoAb as control antibody, respectively.were injected by intraperitoneal (i. p.) administration into nude mice used as models for human T-cell leukemia. SPECT imaging was performed from day 1 to day 8 following i. p. injection. The results showed that radioimmunoimaging of buman tumor xenografts was clearest day 3 after injection in both of ATG and ATG-Dex-DNR groups, whereas it's not the case in Ts-MoAb group. Nude mice were killed 8th day after injection with antibody or conjugate. The tumor, as well as different dissected normal organs including heart, liver, lungs, kidney, femur and intestine, were harvested, weighed precisely, and radioiodine-counted. T/NT ratios in experimental group was greater than 1. 0 (ranged from 1. 246-7. 865). and in control group they were less than 1. 0 (ranged from 0. 263-0. 757, except for tumor/femur ratio). Our results indicated that ATG and ATG-Dex-DNR had specific affinity to cell line of Tcell leukemia CEM.
文摘Using Southern blot, Northern blot and Quick blot methods, we examined the rearrangement and expression of TCR βgene in four early differentiation stage cell lines from human hemopoietic system, namely HL-60, Jurkat, Daudi and Raji cells as well as lymphocytes from 17 acute lymphocytic leukemia (ALL) patients. The results showed. Ⅰ) Rearrangement of TCR βgene was seen in Jurkat cells. A germline pattern was observed in HL-60, Daudi and Raji cells. 2) Eight of 9 patients with T-ALL had cells with rearranged TCR βgene. But two of 3 patients with B-ALL and three of 5 patients with nonT, nonB-ALL also had cells with rearranged TCR βgene. 3) A 1.3 kb full-length transcript and a 1.0 kb truncated transcript were detected in Jurkat cells by probing with <sup>32</sup>P-TCR βcDNA. But some leukemic B cells also expressed an incompleted transcript. 4) TCR βmRNA was detected in six of 8 patients with T-ALL, four of 5 patients with nonT, nonB-ALL and one of 3 patients with B-ALL. But the level of expression was quite differ ent. The dual-rearrangement and the abnormal expression may give us a new clue for researching leukemogenesis.
文摘Background: Human organic cationic transporter1 (Hoct1) is a plasma membrane transporter responsible for the main influx of Imatinib into chronic myeloid leukemia (CML) cells. Single nucleotide polymorphisms (SNPs) in the gene coding for hOCT1 are important factors causing Imatinib resistance. We investigated the frequency of hOCT1 SNP C480G among Egyptian CML patients and its relation to early molecular response as an indicator of treatment outcome. Materials and Methods: Two groups of CML patients were included in this study. Group I consisted of 25 patients responding to Imatinib treatment (Imatinib responsive) and group II consisted of 25 patients resistant to Imatinib (Imatinib resistant). Response criteria were assessed according to the NCCN (National Comprehensive Cancer Network) guidelines 2017. Twenty healthy controls of matched age and sex were also included (group III). For all patients, we studied hOCT1 C480G at initial presentation using Taqman drug metabolism genotyping as well as BCR-ABL percent at diagnosis and after 3 months interval. Results: hOCT1 C480G was present in 32% of studied CML patients. CC (wild) was detected in 68% of group I and 64% of group II. CG (mutant heterozygous) was present in 28% of group I and 36% of group II while GG (mutant homozygous) was detected in only one case in group I. CG was also detected in 15% of control subjects There was no significant difference between hOCT1 C480G polymorphism and Early Molecular Response (χ2 = 0.089, p = 0.765). Conclusions: hOCT1 C480G polymorphism has no association with Imatinib resistance in Egyptian population. However, further studies on a larger number of patients are still needed to confirm this finding.
基金Shanghai Municipal Health Bureau:Traditional Chinese Medicine in Treating with Advanced Hepatocellular Carcinoma(No.ZYSNXD-CC-ZDYJ032)
文摘OBJECTIVE: To probe insights into the reversal effect of bufalin on vincristine-acquired multidrug resistance(MDR) in human leukemia cell line K562/VCR.METHODS: Proliferative inhibition rate and the reversal index(RI) of bufalin were determined by Methyl thiazolyl tetrazolium assay. The uptake of Adriamycin(ADM) in K562/VCR cells, cell cycle and apoptosis rate were determined by flow cytometry(FCM). Cell morphologic changes were observed with Wright-Giemsa staining. The expression of P-glycoprotein(P-gp), multidrug-associated protein-1(MRP1), Bcl-x L and Bax protein were measured by immunocytochemistry.RESULTS: The human leukemia multidrug resistant K562/VCR cells showed no cross-resistance to bufalin. The RIs of bufalin at concentrations of 0.0002,0.001 and 0.005 μmol/L were 4.85, 6.94 and 14.77,respectively. Preincubation of 0.001 μmol/L bufalin for 2 h could increase intracellular ADM fluorescence intensity to 28.07%(P<0.05) and down-regulate MRP1 expression simultaneously, but no remarkable effect was found on P-gp protein. Cell cycle analysis indicated increased apoptosis rate and apparent decreased G2/M phase proportion after treatment with bufalin. When exposed to 0.01μmol/L bufalin, typical morphological changes of apoptosis could be observed. Down-regulation of Bcl-x L and up-regulation of Bax expression in K562/VCR cells could be detected by immunocytochemistry.CONCLUSION: Bufalin could partly reverse the MDR of K562/VCR cells, with a possible mechanism of down-regulating MRP1 expression and activating apoptosis pathway by altering Bcl-x L/Bax ratio.
基金Project supported by the Zhejiang Provincial Natural Science Foundation of China(Nos.LY14H080003 and LY13H290011)
文摘To investigate the potential effects of pure total flavonoid compounds(PTFCs) from Citrus paradisi Macfadyen separately or combined with arsenic trioxide on the proliferation of human myeloid leukemia cells and the mechanisms underlying the action of PTFCs. The effects of PTFCs separately or combined with arsenic trioxide on the proliferation and apoptosis of leukemia cells were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT), fluorescence microscopy, and flow cytometry. Their effects on the expression levels of apoptosisrelated regulators were determined by Western blot assay. PTFCs combined with arsenic trioxide significantly inhibited the growth of Kasumi-1 cells, and apoptosis was confirmed by flow cytometry analysis. Hoechst 33258 staining showed more significant morphological changes and more apoptosis following the combined treatment. Western blots showed changes in the expression of genes for poly ADP-ribose polymerase(PARP), caspase 3/9, and P65. The results indicated that PTFCs separately or combined with arsenic trioxide inhibited proliferation of leukemia cells in vitro and induced their apoptosis by modulating the expression of apoptosis-related regulator genes.
基金supported by start-up funding from St.John's University(Z.S.Chen)
文摘Imatinib,a breakpoint cluster region(BCR)-Abelson murine leukemia(ABL) tyrosine kinase inhibitor(TKI),has revolutionized the treatment of chronic myelogenous leukemia(CML).However,development of multidrug resistance(MDR) limits the use of imatinib.In the present study,we aimed to investigate the mechanisms of cellular resistance to imatinib in CML.Therefore,we established an imatinib-resistant human CML cell line(K562-imatinib) through a stepwise selection process.While characterizing the phenotype of these cells,we found that K562-imatinib cells were 124.6-fold more resistant to imatinib than parental K562 cells.In addition,these cells were cross-resistant to second-and third-generation BCR-ABL TKIs.Western blot analysis and reverse transcription-polymerase chain reaction(RT-PCR) demonstrated that P-glycoprotein(P-gp) and MDR1 mRNA levels were increased in K562-imatinib cells.In addition,accumulation of [14C]6-mercaptopurine(6-MP) was decreased,whereas the ATP-dependent efflux of [14C]6-MP and [3H]methotrexate transport were increased in K562-imatinib cells.These data suggest that the overexpression of P-gp may play a crucial role in acquired resistance to imatinib in CML K562-imatinib cells.
文摘Peripheral blood mononuclear cells(PBMNC)isolated from patients with acuteleukemia(AL)and from normal controls were cultured in a medium containing1000units/ml of recombinant interleukin-2(IL-2).Marked LAK activity was induced onthe third culture day in the normal controls,with the highest cytotoxicity appearing be-tween day 3 and 5,whereas induction of LAK activity in the AL patients began on the5th day of culture,with a peak level appearing at day 15,showing that the peak ofLAK activity was significantly delayed in AL.LAK cells surface phenotyping tests showedthat CD<sub>8</sub> and CD<sub>16</sub> positive cells began to increase significantly from day 5 and reachedthe highest level at week 3,whereas CD<sub>4</sub><sup>-</sup> subclass began to decrease at day 5 anddropped to the nadir at week 3,indicating that LAK activity was positively correlatedwith the proportion of CD<sub>8</sub><sup>+</sup> and CD<sub>16</sub><sup>+</sup> cells,but negatively with that of CD<sub>4</sub><sup>+</sup> cells.
基金Japan Leukemia Research FundGrant-in-Aid for Scientific Research from the Japan Society for the Promotion of Science,Grant/Award Number:No.24500493
文摘Adult T-cell leukemia( ATL) is a mature T-cell malignancy caused by human T-cell leukemia virus type I infection, and 10%-25% of patients show central nervous system( CNS) involvement. CNS involvement significantly reduces survival and there are no effective treatments for CNS involvement. Therefore, an appropriate animal model is required to evaluate the inhibitory effects of novel drugs on the progression of ATL with CNS involvement. Here, we established a mouse model of ATL with CNS involvement using NOD.Cg-Prkdc~ (scid) Il2 rg ^(tm1Wjl)/SzJ mice inoculated with ATL cells intramuscularly in the postauricular region, and these mice showed paraparesis. Of the 10 mice inoculated with ATL cells intramuscularly(I.M.) at 5 weeks of age, 8(80%) showed paraparesis, whereas none of the 10 mice inoculated with ATL cells subcutaneously(S.C.) showed paraparesis. In the I.M. group, PCR detected HTLV-1-specific genes in the thoracic and lumbar vertebrae; however, in the S.C. group, the vertebrae were negative for HTLV-1 genes. Histological analysis revealed a particularly high incidence of tumors, characterized by accumulation of the injected cells, in the thoracic vertebrae of mice in the I.M. group. Tumor cell infiltration was relatively high in the bone marrow. Spinal cord compression caused by invasion of the tumor mass outside the pia mater was observed in the thoracic vertebrae of the spinal cord. In conclusion, we have reported a mouse model of tumor growth with paraparesis that may be used to assess novel therapeutic agents for ATL with CNS involvement.
基金financial support from the National Natural Science Foundation of China (No. 081718110232)
文摘Our previous study demonstrated that human KIAA0100 gene was a novel acute monocytic leukemia-associated antigen (MLAA) gene. But the functional characterization of human KIAA0100 gene has remained unknown to date. Here, firstly, bioinformatic prediction of human KIAA0100 gene was carried out using online softwares; Secondly, Human KIAA0100 gene expression was downregulated by the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) 9 system in U937 cells. Cell proliferation and apoptosis were next evaluated in KIAA0100-knockdown U937 cells. The bioinformatic prediction showed that human KIAA0100 gene was located on 17q11.2, and human KIAA0100 protein was located in the secretory pathway. Besides, human KIAA0100 protein contained a signalpeptide, a transmembrane region, three types of secondary structures (alpha helix, extended strand, and random coil) , and four domains from mitochondrial protein 27 (FMP27). The observation on functional characterization of human KIAA0100 gene revealed that its downregulation inhibited cell proliferation, and promoted cell apoptosis in U937 cells. To summarize, these results suggest human KIAA0100 gene possibly comes within mitochondrial genome; moreover, it is a novel anti-apoptotic factor related to carcinogenesis or progression in acute monocytic leukemia, and may be a potential target for immunotherapy against acute monocytic leukemia.