Mechanism Research of Magnetic Nanoparticle Fe3O4 and 5-Bromotetrandrine On Reversal of Multidrug Resistance in K562/A02 Leukemic Cells.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 4827-4827
Author(s):  
Bao-An Chen ◽  
Wei-Wei Wu ◽  
Jian Cheng ◽  
Feng Gao ◽  
Wen-Lin Xu ◽  
...  
Keyword(s):  
Multidrug Resistance ◽  
Cell Line ◽  
Magnetic Nanoparticle ◽  
Conflicts Of Interest ◽  
Synergetic Effect ◽  
Leukemic Cells ◽  
Reversal Agents ◽  
Mechanism Research ◽  
Magnetic Nanoparticles Fe3o4 ◽  
Fe3o4 Mnps

Abstract Abstract 4827 Purpose The present study aimed to research the machenism of magnetic nanoparticles Fe3O4 (Fe3O4-MNPs) and 5-bromotetrandrine (BrTet) on multidrug resistance cell line K562/A02 solitarily or symphysially. Mothed The proliferation of K562 and K562/A02 cells, and the cytotoxicity of PMBCs which were cultured with daunomycin (DNR) alone or in combination with Fe3O4-MNPs (0.1, V/V), BrTet (0.5μM) or both for 48 h, were evaluated by MTT assay. DNR accumulation of K562, K562/A02 cells and PMBCs were analyzed by fluorospectrophotometry after incubated with 2μM DNR in the absence or presence with Fe3O4-MNPs (0.1 V/V), BrTet (0.5μM) or both for 48 h. Real time–PCR analyses and western blotting were performed to examine the mRNA and proteins level, respectively. Result The results showed that the combination of Fe3O4-MNPs and BrTet with effective concentration could exaggerate cytotoxicity against MDR cell line K562/A02 significantly. Flow cytometry assay showed that 0.5μM BrTet in combination with Fe3O4-MNPs (0.1, V/V) significantly enhanced the intracellular accumulation of DNR in K562/A02 cells and its potency was greater than that of BrTet or Fe3O4-MNPs alone at the same concentrations. While both Fe3O4-MNPs and BrTet in company with DNR did not increase the cytotoxicity to PMBCs. Both BrTet and Fe3O4-MNPs inhibited the overexpression of MRP1, MRP2, MRP4 and MRP5, and down regulated, mrps mRNA expression in K562/A02 cells to some extent. Conclusion We propose that Fe3O4-MNPs loaded with DNR and BrTet probably have synergetic effect on reversal in multidrug resistance. However, this combination shows less cytotoxicity to normal cells and reveals better target. The results may provide evidence for clinic application of them as reversal agents of drug resistance. Disclosures No relevant conflicts of interest to declare.

Reversal of Multidrug Resistance by Magnetic Fe3O4 Nanoparticle Copolymerizating Daunorubicin and mdr1-shRNA Expression Vetor in Leukemia Cells.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 4829-4829
Author(s):  
Bao-An Chen ◽  
Peipei Mao ◽  
Jian Cheng ◽  
Feng Gao ◽  
Jia-Hua Ding ◽  
...  
Keyword(s):  
Multidrug Resistance ◽  
Cell Line ◽  
Recombinant Plasmid ◽  
Conflicts Of Interest ◽  
Transfection Efficiency ◽  
Resistance Index ◽  
Leukemic Cells ◽  
Target Sequence ◽  
Shrna Expression ◽  
Mdr 1

Abstract Abstract 4829 Object In many instances, Multidrug resistance (MDR) is mediated by increased expression at the cell surface of the MDR1 gene product, P-glycoprotein (P-gp), a 170-kD energy-dependent efflux pump. The aim of this study was to investigate the potential benefit of combination therapy with magnetic nanoparticle of Fe3O4 (MNP(Fe3O4)) and mdr1-shRNA Expression vetor.in K562/A02 leukemic cells. Methods To synthesis short hairpin RNA (shRNA)aiming divectly at the target sequence,we choice the 3491-3509,1539-1557and 3103-3121 nucleotide of mdr-1 mRNA as targets. Cloning in the plasmid vetor PGCSilencer-U6-neo-GFP, The recombinant plasmid vetors were called for PGY1-1,PGY1-2 and PGY1-3.The recombinant plasmid vetors were transfected into the cell 1ines K562/A02 by lipofection. After transfected 48 hours,the inhibition of mdr-1mRNA expression and the expression of P-gp was detected by realtime–PCR and Weston-blot, screening the recombinant plasmid vetor which has the most greatest mdr-1 gene inhibition ratio is PGY1-2.Analysis of the reveral ratio of multidrug resistance, the concentration of DNR and the content of mdr-1 gene and P-gp in K562/A02 cell line. Results The combination of daunorubicin (DNR) with either MNP(Fe3O4) or PGY1-2 exerted a potent cytotoxic effect on K562/A02 cells, while MNP(Fe3O4) and PGY1-2 cotreatment can synergistically down regulation the expression of mdr-1 gene and the expression of P-gp(P<0.05). The transfection efficiency was 20%; the concentration of DNR in K562/A02 cell line was obviously elevated (P<0.05);the multidrug resistance index of K562/A02 cell line was obviously decreased (P<0.05). Conclusion MNP(Fe3O4) and PGY1-2 cotreatment can synergistically reveral multidrug resistance. Thus our in vitro data strongly suggests a potential clinical application of MNP(Fe3O4) and PGY1-2 combination on CML. Disclosures No relevant conflicts of interest to declare.

The Study of Bortezomib Alone or in Combination with Arsenic Trioxide on Multidrug Resistance of HL60/ADR cells.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 4823-4823
Author(s):  
Fanyi Meng ◽  
Ming Huang
Keyword(s):  
Flow Cytometry ◽  
Multidrug Resistance ◽  
Cell Line ◽  
Arsenic Trioxide ◽  
Cell Apoptosis ◽  
Conflicts Of Interest ◽  
Synergistic Effects ◽  
Caspase 9 ◽  
Reduce Cell Survival ◽  
Apoptosis Proteins

Abstract Abstract 4823 INTRODUCTION Proteĉ¢msome inhibitor bortezomib has used in treatment of hematology malignancies widely. We found it may reduce cell survival rate of HL60/ADR cell line and induce cell apoptosis in previous study. Now we are to investigate the effect of bortezomib alone or combined with arsenic trioxide (As2O3) on reversing multidrug resistance of HL60/ADR cell line and the possible machines. METHODS HL60/ADR cells were incubated with bortezomib at different doses alone and in combination with As2O3. The proliferation ratio was observed by MTT assay. Cell apoptosis was studied by fluorescence microscopy and flow cytometry. Intracellular concentration of daunorubicin (DNR) and multidrug resistance related protein-1 (MRP1) was determined by flow cytometry. P65Ap-p65Abcl-2AbaxAcaspase-3Acaspase-9APARP proteins were determined by western blot. RESULTS In bortezomib-treated tumor cells, inhibition rate increased in time- and dose-dependently, as well as apoptotic cells. Compared to bortezomib alone, combination with As2O3 inhibited the proliferation and induced the apoptosis of HL60/ADR cells more evident. Bortezomib can enhance the intraceflular accumulation of DNR and decrease MRP1 in HL60/ADM cells. The dual combination of As2O3 with bortezomib presents a superior anticancer and MRP1-decreased efficiency to either one of the drugs alone. Bortezomib can also elevate the expression of bax, caspase-3, caspase-9, PARP, and decelerate the expression of bcl-2, NF-κB p65, p-p65. CONCLUSIONS Bortezomib can reverse multidrug resistance of HL60/ADR cells and decrease the expression of MRP1 in cells. When combined with As2O3, it appears to synergistic effects. Its mechanisms might be associated with the inhibition of NF-κB activation, also with inhibiting anti-apoptosis proteins, boosting pro-apoptosis proteins, with followed activating caspase pathway. Disclosures: No relevant conflicts of interest to declare.

All-Trans-Retinoic Acid (ATRA) Causes Extensive Differentiation In the NPM Mutant, Non-APL Leukemic Cell Line OCI-AML3

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3305-3305 ◽  
Author(s):  
Matthew A. Kutny ◽  
Steven J. Collins ◽  
Keith Loeb ◽  
Roland B. Walter ◽  
Soheil Meshinchi
Keyword(s):  
Cell Viability ◽  
Cell Count ◽  
Cell Line ◽  
Cell Lines ◽  
Time Course ◽  
Conflicts Of Interest ◽  
Live Cell ◽  
Leukemic Cells ◽  
Viable Cell Number ◽  
Nuclear Segmentation

Abstract Abstract 3305 The differentiating agent ATRA has been used successfully in the treatment of acute promyelocytic leukemia (APL). By comparison, non-APL AML has not shown similar sensitivity to ATRA induced differentiation. Recent data has suggested that a subset of de novo AML patients with nucleophosmin (NPM1) mutations may benefit from addition of ATRA to conventional therapy. The NPM1 gene has several functions affecting cell cycle proliferation including regulation of ribosome biogenesis and centrosome duplication and it acts as a histone chaperone. Mutation of the NPM1 gene leads to differentiation arrest contributing to AML pathogenesis. We hypothesized that leukemia cells with NPM1 mutations could be induced to undergo differentiation. We tested this hypothesis with the NPM1 mutant AML cell line OCI-AML3 and compared the results to identical assays using the AML cell line HL-60 which has been previously well documented to differentiate in response to ATRA therapy. OCI-AML3 and HL-60 cell lines were treated for 5 days with control media and four ATRA doses including 0.2 μM, 1 μM, 5 μM, and 25 μM. Cell viability was assessed by flow cytometry. Compared to the control condition, OCI-AML3 cells treated with the lowest dose of ATRA (0.2 μM) had a live cell count 21.6% of the control. HL-60 cells treated at even the highest ATRA dose (25 uM) had a live cell count 79.3% of the control. Due to the sensitivity of OCI-AML3 cells to the toxic effects of ATRA, the experiment was repeated with lower doses of ATRA including 0.001 μM, 0.01 μM and 0.1 μM. At the lowest dose of ATRA (0.001 μM), OCI-AML3 cells demonstrated a cell viability of 49% with further decrease to 26% at 0.1 μM dose of ATRA. At similar ATRA doses, cell viability for HL-60 cells was 91% and 85%, respectively (see table 1). Table 1: Cell viability as a percent of control cells after 5 days of treatment at three different doses of ATRA in OCI-AML3 and HL-60 cell lines. Cell Line: ATRA 0.001 μM ATRA 0.01 μM ATRA 0.1 μM OCI-AML3 49% 33% 26% HL-60 91% 91% 85% We subsequently determined the time course of changes in cell growth and the extent of differentiation at each point was determined by morphologic assessment. Both cell lines were treated with ATRA at doses of 0.001 μM, 0.01 μM, 0.1 μM, and 1 μM for a total of 4 days. Each day viable cell number was determined. In contrast to the HL-60 cells which had continued growth in lower ATRA doses, OCI-AML3 cells demonstrated exquisite sensitivity to growth arrest at the lowest doses of ATRA. Cell morphology was assessed daily with modified Wright-Giemsa staining of cells. Cells were examined for signs of myeloid differentiation including decrease in nuclear to cytoplasmic (N/C) ratio, nuclear segmentation, and cytoplasmic granules and vacuoles. At the lowest dose of ATRA (0.001 μM), after 4 days of exposure, significant number of OCI-AML3 cells demonstrated morphologic evidence of differentiation. At this ATRA dose and exposure interval, HL-60 cells showed no evidence of differentiation. At an ATRA dose of 1 μM (considered a standard dose used for differentiation of HL-60 cells), the OCI-AML3 cells showed differentiation changes as early as day 2 with nuclear segmentation and decreased N/C ratio while HL-60 cells did not show any change at this time point. After 4 days of ATRA exposure, most OCI-AML3 cells showed segmented nuclei and vacuolated cytoplasm, whereas HL-60 cells showed less distinct signs of differentiation with some cytoplasm granules and cup shaped nuclei. This data suggests that leukemic cells with NPM mutations may be susceptible to the pro-differentiating properties of ATRA. Further substantiation of this data with primary human specimens may ultimately provide the rationale for a novel therapeutic option using ATRA-based differentiation therapy for subsets of non-APL AML. Disclosures: No relevant conflicts of interest to declare.

Establishment and Characterization of a Novel Human Myeloid Leukemia Cell Line, AMU-AML1, Carrying t(12;22)(p13;q11) with No Fusion of MN1-TEL

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 4375-4375
Author(s):  
Mayuko Goto ◽  
Ichiro Hanamura ◽  
Motohiro Wakabayashi ◽  
Hisao Nagoshi ◽  
Tomohiko Taki ◽  
...  
Keyword(s):  
Cell Line ◽  
Cell Lines ◽  
Myeloid Leukemia ◽  
Conflicts Of Interest ◽  
Leukemia Cell ◽  
Leukemic Cells ◽  
Leukemia Cell Line ◽  
Chromosome Band ◽  
Structural Abnormality ◽  
Myeloid Leukemia Cell

Abstract Abstract 4375 Leukemia cell lines are ubiquitous powerful research tools that are available to many investigators. In balanced chromosomal aberration in leukemia, a chimeric fusion gene formed by genes existing on breakpoints is frequently related to leukemogenesis. Cytogenetic abnormalities of chromosome band 12p13 are detected non-randomly in various hematological malignancies and usually involved TEL, which encodes a protein of the ETS transcription factor family. Chromosome band 22q11-12 is one of partners of translocation 12p13 and t(12;22)(p13;q11-12) results in fusion of TEL and MN1 or in just the partial inactivation of TEL. It is important to analyze precisely the breakpoint in a non-random translocation such as t(12;22)(p13;q11-12) and in addition it contributes to the better understanding of the molecular pathogenesis of leukemogenesis. In this study, we established a novel human myeloid leukemia cell line, AMU-AML1, having t(12;22) from a patient with acute myeloid leukemia with multilineage dysplasia and analyzed its characters. Mononuclear cells were isolated by Ficoll-Hypaque sedimentation from patient's bone marrow before initiation of chemotherapy and cultured in RPMI 1640 supplemented with 10% heat-inactivated fetal bovine serum (FBS). After 3 months, cell proliferation became continuous. The cell line, named AMU-AML1, was established. In AMU-AML1, the following pathogens were negative for EBV, CMV, HBV, HCV, HIV-1, HTLV-1 and mycoplasma. A doubling time of AMU-AML1 cells was about 96 hours. Proliferation of the cells was stimulated by rhG-CSF (10 ng/ml), rhGM-CSF (10 ng/ml), M-CSF (50 ng/ml), rhIL-3 (10 ng/ml) and rhSCF (100 ng/ml) but not by IL-5 (10 ng/ml), rhIL-6 (10 ng/ml), and rhEPO (5 U/ml). AMU-AML1 was positive for CD13, CD33, CD117 and HLA-DR, negative for CD3, CD4, CD8 and CD56 by flow cytometry analysis. G-banding combined with SKY analysis of AMU-AML1 cells showed single structural abnormality; 46, XY, t(12;22)(p13;q11.2). Double-color FISH using PAC/BAC clones listed in NCBI website and array CGH analyses indicated that the breakpoint in 12p13 was within TEL or telomeric to TEL and it of 22q11 was centromeric to MN1. A chimeric MN1-TEL transcript and fusion protein of MN1-TEL could not be detected by RT-PCR and western blot analysis. The wild type of MN1 protein was strongly expressed in AMU-AML1 compared with other leukemic cell lines with t(12;22), MUTZ-3 and UCSD/AML1. Our data suggest that AMU-AML1 had a t(12;22)(p13;q11.2) without fusion of MN1-TEL and the expression level of MN1 protein was relatively high, which might have some effects on leukemogenesis. In conclusion, AMU-AML1 is a useful cell line to analyze the biological consequences of the leukemic cells with t(12;22)(p13;q11.2) but no fusion of MN1-TEL. Disclosures: No relevant conflicts of interest to declare.

In Vitro Effect Of VPA Together With ATRA and Ara-C On Proliferation and Viability Of Pediatric AML Cell Line THP-1

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 4924-4924
Author(s):  
Sema Anak ◽  
Ayca Gul Kanbay ◽  
Cagri Gulec
Keyword(s):  
Cell Line ◽  
Animal Studies ◽  
Conflicts Of Interest ◽  
Bipolar Disorders ◽  
Mood Stabilizer ◽  
Leukemic Cells ◽  
Pcr Method ◽  
Pediatric Aml ◽  
Vitro Effect

Abstract In addition to its HDAC inhibitory property, Valproic acid is also known as anticonvulsant agent and mood stabilizer in the treatment of bipolar disorders. Due to its HDAC inhibitory activity and its safety in long-term usage, VPA is presumed to be a good candidate for cancer treatment. It is known that VPA induces apoptosis in leukemic cells, while not in normal cells. VPA is reported as an effective agent in treatment of pediatric AML in clinical studies and  is also well tolerated in children. In this study, the in vitro effect of the combination of HDAC inhibitor VPA with Ara-C and ATRA which are used in AML therapy, is investigated on AML cells. For this purpose, the effect of VPA, Ara-C and ATRA on proliferation of AML cell line THP-1 is tested in cell culture condition. To assess the effect on cell proliferation, p21 expression was measured by RT-PCR method. The use of VPA alone, did not affect the cell viability, while increasing the expression of the p21 gene. VPA in combination with Ara-C, increased the expression of p21 gene more than the other combinations. Thus it is determined that the p21 gene expression is higher as a result of known cell cycle stops. In this study, the understanding of how effective is VPA together with ATRA and/or Ara-C on AML cells, might be a good start for animal studies and clinical trials as a remarkable data for the development of new chemotherapeutic protocols. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Effect of DMSA Modified Fe3O4 and Multidrug Resistance Modulator HZ08 on the Reversal of Multidrug Resistance in K562/A02 Cell Line

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 5235-5235
Author(s):  
Fei Shen ◽  
Mingfei Zhou ◽  
Xuzhang Lu ◽  
Yanping Chen ◽  
Baoan Chen
Keyword(s):  
Multidrug Resistance ◽  
Cell Line ◽  
Real Time ◽  
Caspase 3 ◽  
Conflicts Of Interest ◽  
Morphological Changes ◽  
Leukemia Cell ◽  
Cell Counting ◽  
Leukemia Cell Line ◽  
Gene And Protein Expression

Abstract The objective of the present study was to investigate the reversible effect of HZ08 and daunorubicin(DNR) combined with dimercaptosuccinic acid modified iron oxide (DMSA-Fe3O4) magnetic nanoparticles (MNPs) in human chronic leukemia cell line K562/A02, and the mechanism potentially involved. The growth inhibition rate of K562/A02 cells was determined by Cell Counting Kit-8 (CCK-8) assay. Cell apoptosis and intracellular concentration of DNR were detected by flow cytometry (FCM). DAPI staining was used to view apoptotic cellular morphology. Subsequently, transcription levels of MDR1 mRNA and expression levels of P-glycoprotein (P-gp) and caspase-3 were determined by real time polymerase chain reaction (real-time PCR) and Western blotting analysis, respectively. group clearly exhibited more morphological changes (severe structural alterations) than other groups. In addition, transcription of MDR1 gene and protein expression of P-gp and caspase-3 of K562/A02 cells were regulated at the most remarkable extent in DNR-HZ08-MNPs group when compared with other groups. These findings suggest that the remarkable effects of the novel DNR-HZ08-MNPs on multidrug resistant K562/A02 leukemia cells would be a promising strategy for overcoming multidrug resistance. Disclosures No relevant conflicts of interest to declare.

TEL-AML1 Affects the Regulation of Cytoskeleton and Causes Alteration In Cellular Adhesive and Migratory Properties In An In Vitro Model of Pre-Leukemia.

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3624-3624
Author(s):  
Chiara Palmi ◽  
Grazia Fazio ◽  
Ilaria Brunati ◽  
Valeria Cazzaniga ◽  
Valentina André ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Line ◽  
Conflicts Of Interest ◽  
Fusion Gene ◽  
Expression System ◽  
Leukemic Cells ◽  
Calcium Flux ◽  
Actin Dynamics ◽  
Childhood Leukaemia

Abstract Abstract 3624 Introduction: The t(12;21) chromosome translocation generating TEL-AML1 chimeric fusion gene is a frequent initiating event in childhood leukaemia. Its impact is to generate a clone of covert, clinically silent pre-leukemic B cell progenitors. The leukemia arises only following second, post-natal hit/genetic events occurring years later. Moreover, relapse of leukemia is frequently arising from the pre-leukemic clone. Aim of our study is to investigate how TEL-AML1 expression can sustain this covert condition for many years. In a recent paper we described that the fusion gene rendered the B precursors resistant to the inhibitory activity of TGFbeta. Here we want to inquire into other factors that can explain the positive selection of the pre-leukemic clones over the normal counterpart. In particular, given the importance of the interaction with the microenvironment for survival signals for normal and leukemic stem cells, we question if the fusion gene causes changes in cellular adhesive and migratory properties. Methods: the study was performed by using two different models: i) a TEL-AML1 inducible expression system on the murine pro-B Ba/F3 cell line and ii) murine primary B lymphocytes (pre-BI cells) isolated from fetal liver, stably transduced with the pMIGR1-TEL-AML1-IRES-GFP construct. Gene expression assays were performed by using TaqMan (Applied Biosystems) and PCR Array technologies (SABioscences). Results: The expression of TEL-AML1 in Ba/F3 cell line causes over-expression of genes regulators of the cytoskeleton, specifically involved in cellular movement and in the regulation of actin dynamics. This gene expression alteration results in changes in the cellular morphology and phenotype: the cells acquire long extensions and several molecules involved in cell adhesion and migration are disregulated. Moreover, the TEL-AML1 positive cells present an increased ability to adhere to the ICAM1 substrate, but they also show a significant defect in the chemotactic response to CXCL12 in transwell migration assays in vitro, although the expression and the recycling of CXCR4 receptor are unaffected. This inability is not due to defects to migrate in general, as spontaneous motility is enhanced, but it is associated with a defect in CXCR4 signaling. In particular, CXCL12 calcium flux and ERK phosphorylation were inhibited. Those results have been confirmed in murine PreBI primary cells. Conclusions: in our murine models, TEL-AML1 affects the cytoscheleton regulation and causes alteration in cellular adhesive and migratory properties. We are now investigating how these alterations can give advantages to the pre-leukemic cells in the pathogenesis of TEL-AML1–expressing leukemia. Disclosures: No relevant conflicts of interest to declare.

scholarly journals p53-Induced Autophagy Regulates Chemotherapy and Radiotherapy Resistance in Multidrug Resistance Cancer Cells

Dose-Response ◽  
2021 ◽  
Vol 19 (4) ◽  
pp. 155932582110480
Author(s):  
Shumei Ma ◽  
Dejuan Kong ◽  
Xinxin Fu ◽  
Lin Liu ◽  
Yi Liu ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Multidrug Resistance ◽  
Cell Line ◽  
Ovarian Cancer Cell Line ◽  
Mutant Cell ◽  
Leukemia Cell ◽  
Cancer Cell Line ◽  
Leukemic Cells ◽  
Leukemia Cell Line ◽  
Human Leukemia

Background Multidrug resistance (MDR), a major problem in oncology therapy, limits the effectiveness of anticancer drugs. Although p53 functions as a tumor suppressor, the associations between p53 status, autophagy, and MDR are complicated and conditional. Method  In this report, p53-null human ovarian cancer cell line SKOV3 and its MDR phenotype SKVCR and human leukemia cell line CEM and its MDR phenotype CEM-VLB) (p53 mutant cell line) were used. Results  Compared to parental SKOV3, the mRNA and protein levels of MAPLC3-II and Beclin1 were higher in SKVCR cells. The inhibition of autophagy by 3-MA significantly sensitized SKVCR to VCR. Conversely, in drug-resistant leukemic cells CEM-VLB, the expressions of Beclin1 and MAPLC3-II were lower than CEM. CEM and CEM-VLB cells were treated with VLB .01 or 0.5 μg/mL, respectively, and the expression of p53 and autophagy up-regulated after VLB (.01 μg/mL) treatment in CEM cells. The percentage of S-phase and G2/M phase cells up-regulated significantly by .01 μg/mL VLB in CEM, which may relate to the status of p53 of CEM cells. A combination of radiation with 3-MA significantly increased apoptosis in CEM-VLB cells. Conclusion  Our discovery found that p53 is an important regulator controlling the balance between autophagy and MDR, as a potential drug target for ovarian cancer and leukemia.

Mechanism Research of Reversal in Multidrug Resistance by Magnetic Nanoparticle Fe3O4 Syndesis with 5-Bromotetrandrine and Daunomycin

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 5064-5064
Author(s):  
Bao-An Chen ◽  
Wei-wei Wu ◽  
Jian Cheng ◽  
Feng Gao ◽  
Wen-lin Xu ◽  
...  
Keyword(s):  
Multidrug Resistance ◽  
Magnetic Nanoparticle ◽  
Statistical Significance ◽  
Flow Cytometry Assay ◽  
Mechanism Research ◽  
Reversal Mechanism ◽  
The Mean ◽  
Nano Fe3o4 ◽  
Mdr Reversal

Abstract Objective To evaluate the MDR reversal activity of magnetic nanoparticle Fe3O4 (Nano-Fe3O4) and 5-bromotetrandrine (BrTet) on multidrug resistance cell line K562/A02 solitarily or symphysially, and to investigate the reversal mechanism of this coopration. Methods The proliferation of K562 and K562/A02 cells which were cultured with daunomycin (DNR) alone or in combination with Nano-Fe3O4, BrTet or both for 48h were evaluated by MTT assay. DNR accumulation and P-gp of K562 and K562/A02 were analyzed by fluorospectrophotometry. Results The IC50 of DNR for K562 and K562/A02 cells were 2.74±0.19μM and 32.33±8.40μM, respectively; but the sensitivity of K562/A02 cells to DNR was partially restored after culturing with Nano-Fe3O4, BrTet solitarily and symphysially (the IC50 were 7.04±0.85μM, 4.25±2.16μM, 1.80±0.30μM; the FR were 4.32, 7.61, 17.96, respectively), but had no effects on K562 cell lines. The differences had statistical significance. Flow cytometry assay showed that Nano-Fe3O4 and BrTet increased the DNR accumulation in K562/A02 cells, especially in the group of synergia of these two agents. The mean fluorescence intensity of endocellular DNR increased from 2614 pretreated with DNR only to 4783 incubated with these two reversal reagents, while the values were 3364, 4077 for incubating with Nano-Fe3O4 and BrTet respectively. P-gp were down regulated through pretreating with Nano-Fe3O4, BrTet alone and symphysially in K562/A02 cells by fluorospectrophotometry assay. Conclusion Nano-Fe3O4 and BrTet synergisticly showed significant MDR reversal activity in vitro. The reversal activity may be related to the inhibition of P-gp overexpression and the increasing of the anticancer drug accumulation intracelluarly.

Sign in / Sign up

Export Citation Format

Share Document