RESUMO
Although microRNAs have been elaborated to participate in various physiological and pathological processes, their functions in TRAIL resistance of acute myeloid leukemia (AML) remain obscure. In this study, we detected relatively lower expression levels of miR-424&27a in TRAIL-resistant and semi-resistant AML cell lines as well as newly diagnosed patient samples. Overexpression of miR-424&27a, by targeting the 3'UTR of PLAG1, enhanced TRAIL sensitivity in AML cells. Correspondingly, knockdown of PLAG1 sensitized AML cells to TRAIL-induced apoptosis and proliferation inhibition. We further found that PLAG1 as a transcription factor could reinforce Bcl2 promoter activity, causing its upregulation at the mRNA level. Both downregulated PLAG1 and elevated expression of miR-424&27a led to Bcl2 downregulation and augmented cleavage of Caspase8, Caspase3 and PARP in the presence of TRAIL. Restoration of Bcl2 could eliminate their effects on AML TRAIL sensitization. Overall, we propose that miR-424&27a and/or PLAG1 might serve as novel therapeutic targets in AML TRAIL therapy.
Assuntos
Proteínas de Ligação a DNA/biossíntese , Resistencia a Medicamentos Antineoplásicos/genética , Leucemia Mieloide Aguda/genética , MicroRNAs/metabolismo , Adolescente , Adulto , Idoso , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Criança , Feminino , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica/genética , Humanos , Leucemia Mieloide Aguda/metabolismo , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Adulto JovemRESUMO
To investigate the clinical efficacy of adoptive immunotherapy using dendritic cells (DC) and cytokine-induced killer (CIK) cells combined with chemotherapy in multiple myeloma. The immunomodulatory effect of the therapy was discussed by detecting the levels of peripheral blood T cell subsets and CD4(+)CD25(+) regulatory cells (Treg). Fifty MM patients were randomly divided into two groups: 24 cases in the simple chemotherapy group and 26 cases in the combined therapy group (chemotherapy plus DC/CIK immunotherapy). The therapeutic efficacy and the proportions of peripheral blood T cell subsets and Treg cells were compared between the two groups. The cellular immunity indicators were also compared, including IL-2, IFN-γ, IL-4, IL-10, AgNORs ratio and TGF-ß. After 3 weeks of treatment, the life quality and clinical efficacy of the combined therapy group were superior to those of the simple chemotherapy group (P<0.05). CD3(+)CD8(+) ratio, CD4(+)CD25(+) ratio, CD4(+)CD25(+)/CD4(+) ratio, CD4(+)CD25(+)FoxP3(+)/CD4(+)CD25(+) ratio, IL-4, IL-10 and TGF-ß levels of the combined therapy group were obviously lower than those of the simple chemotherapy group (P<0.05). The CD3(+)CD4(+)/CD3(+)CD8(+) ratio, AgNOR ratio, IL-2 and IFN-γ level and positive rate of NKG2D in the combined therapy group were significantly higher than those of the simple chemotherapy group (P<0.05). These results indicated better immunomodulatory effect of the combined therapy. DC/CIK immunotherapy combined with chemotherapy has a good clinical efficacy and prospect for MM, reversing the Th1 to Th2 shift and increasing the anti-tumor capacity of the immune system.
Assuntos
Antineoplásicos/administração & dosagem , Células Matadoras Induzidas por Citocinas/transplante , Células Dendríticas/transplante , Imunoterapia Adotiva/métodos , Mieloma Múltiplo/terapia , Adulto , Bortezomib/administração & dosagem , Dexametasona/administração & dosagem , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/imunologia , Subpopulações de Linfócitos T/imunologiaRESUMO
UNLABELLED: Aberrant expression of forkhead box protein M1 (FoxM1) contributes to carcinogenesis in human cancers, including acute myeloid leukemia (AML), suggesting that the discovery of specific agents targeting FoxM1 would be extremely valuable for the treatment of AML. Curcumin, a naturally occurring phenolic compound, is suggested to possess anti-leukemic activity; however, the underlying mechanism has not been well elucidated. In this study, we found that curcumin inhibited cell survival accompanied by induction of G2/M cell cycle arrest and apoptosis in HL60, Kasumi, NB4, and KG1 cells. This was associated with concomitant attenuation of FoxM1 and its downstream genes, such as cyclin B1, cyclin-dependent kinase (CDK) 2, S-phase kinase-associated protein 2, Cdc25B, survivin, Bcl-2, matrix metalloproteinase (MMP)-2, MMP-9, and vascular endothelial growth factor (VEGF), as well as the reduction of the angiogenic effect of AML cells. We also found that specific downregulation of FoxM1 by siRNA prior to curcumin treatment resulted in enhanced cell survival inhibition and induction of apoptosis. Accordingly, FoxM1 siRNA increased the susceptibility of AML cells to doxorubicin-induced apoptosis. More importantly, curcumin suppressed FoxM1 expression, selectively inhibited cell survival as well as the combination of curcumin and doxorubicin exhibited a more inhibitory effect in primary CD34(+) AML cells, while showing limited lethality in normal CD34(+) hematopoietic progenitors. These results identify a novel role for FoxM1 in mediating the biological effects of curcumin in human AML cells. Our data provide the first evidence that curcumin together with chemotherapy or FoxM1 targeting agents may be effective strategies for the treatment of AML. KEY MESSAGE: Curcumin inhibited AML cell survival and angiogenesis and induced chemosensitivity. Aberrant expression of FoxM1 induces AML cell survival and chemoresistance. Inactivation of FoxM1 contributes to curcumin-induced anti-leukemic effects. Curcumin together with FoxM1 targeting agents may be effective for AML therapy.
Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Curcumina/farmacologia , Fatores de Transcrição Forkhead/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Proteína Forkhead Box M1 , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismoRESUMO
BACKGROUND: Immunological disorder has shown to be related to the pathogenesis of acute myeloid leukemia (AML). The microenvironment of AML is immunosuppressive, favoring the survival of malignant hematopoietic cells. However, the systematic research on AML abnormal immune microenvironment, especially the T helper (Th) cells imbalance, remains unsettled. DESIGN AND METHODS: The levels of cytokines in bone marrow plasma including Th1-associated cytokine (IFN-γ), Th2-associated cytokine (IL-4), Th17-associated cytokines (IL-17, IL-6, TGF-ß, and IL-21), regulatory T cell (Treg)-associated cytokines (IL-35 and IL-10) and Th22-associated cytokine (IL-22) were examined by enzyme-linked immunosorbent assay (ELISA) in AML patients and controls. The relative expression levels of IL-4, IL-10, and IL-21 mRNA were analyzed by real time polymerase chain reaction (PCR). RESULTS: Significant differences on cytokine levels tested were observed among the AML newly-diagnosed (ND) patients, AML patients in complete remission (CR) and controls except IL-21 and IL-35. In AML-ND group IFN-γ level was positively correlated with IL-21 or IL-22 level. Additionally, significant associations were observed between IL-17, IL-21 and some clinical characteristics. CONCLUSION: Our results showed that many cytokines were abnormal in AML bone marrow microenvironment. The dysregulation of Th subsets cytokines is thought to contribute to the pathogenesis of AML.
Assuntos
Células da Medula Óssea/imunologia , Citocinas/metabolismo , Leucemia Mieloide Aguda/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Reguladores/imunologia , Adolescente , Adulto , Idoso , Carcinogênese , Células Cultivadas , Microambiente Celular , Citocinas/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Equilíbrio Th1-Th2 , Adulto JovemRESUMO
OBJECTIVE: To investigate the comparability of bcr-abl (P210) transcript levels detected in different hospitals. METHODS: Ten hospitals in China took part in the four times of sample exchange and comparisons from April, 2010 to August, 2011. The exchange samples were prepared by Peking University People's Hospital. Firstly, the BCR-ABL (P210)(+) cells from a newly diagnosed chronic myeloid leukemia patient were 10-fold serially diluted by BCR-ABL (P210)(-) cells and they covered 4 magnitudes. Then, TRIzol reagents were thoroughly mixed with cells in each tube. Every 12 samples (three samples per magnitude) were sent to the other 9 hospitals. The cell number of each sample was 8×10(6). The detection of bcr-abl transcript levels by real-time quantitative PCR were performed in every hospital according to their own protocols. Conversion factors (CF) were calculated using regression equation. RESULTS: Differences in bcr-abl transcript levels did exist among results of 10 hospitals in each comparison. In general, the results of the most of hospitals were in line with the dilutions of cells. CF of every hospital fluctuated. Three hospitals had relatively stable CF, and their ranges were 2.8 - 5.2, 1.2 - 2.8 and 2.2 - 6.8, respectively; two hospitals had unstable CF with ranges 0.76 - 7.0 and 2.1 - 18.7; three hospitals couldn't be calculated CF one or two times because of the significant deviation of the results from the actually bcr-abl transcript levels, and their ranges of CF which could be calculated were 1.9 - 19.2, 3.6 - 7.6 and 0.18 - 14.7; One hospital only had two CF (3.3 and 5.0) because of the replacement of an important reagent during the period of comparisons. CONCLUSIONS: Comparability of bcr-abl (P210) transcript levels between different hospitals could be achieved through CF which acquired by sample exchange and comparison. The stable and reliable detection system is the premise to acquire correct CF.
Assuntos
Proteínas de Fusão bcr-abl/isolamento & purificação , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Células da Medula Óssea , China , Proteínas de Fusão bcr-abl/genética , Hospitais , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
BACKGROUND: Immunological mechanisms are increasingly recognized in the progression of myelodysplastic syndrome (MDS). Early-stage MDS (E-MDS) is characterized by autoimmune-mediated myelosuppression whereas late-stage MDS (L-MDS) involves immune evasion, giving dysplastic cells growth potential to progress into acute myeloid leukemia. T-helper (Th) 22 is involved in the pathogenesis of inflammatory autoimmunity and tumorigenesis. The roles of Th22 cells in the pathophysiology of E-MDS and L-MDS remain unsettled. DESIGN AND METHODS: We studied 37 MDS patients (E-MDS, n = 17; L-MDS, n = 20) and 20 healthy controls to characterize their peripheral blood (PB), as well as 25 MDS patients and 10 healthy controls to characterize their bone marrow(BM). The expression of Interleukin-22 (IL-22), IL-17 or interferon gamma (IFN-γ) was examined in E-MDS, L-MDS patients and controls by flow cytometry. The mRNA expression levels of RAR-related orphan receptor C (RORC), IL-6, tumor necrosis factor alpha (TNF-α) and IL-23 in peripheral blood mononuclear cells (PBMCs) were determined by real-time quantitative polymerase chain reaction. The levels of IL-22 and IL-17 both in PB and BM plasma were examined by enzyme-linked immunosorbent assay. RESULTS: In E-MDS, peripheral Th17 cells were significantly elevated and correlated with peripheral Th22 cells compared with healthy controls and L-MDS. Significantly higher levels of peripheral Th22 expansion, mRNA expression of IL-6, TNF-α and lower level of RORC mRNA expression were observed in L-MDS compared with E-MDS. No statistical difference was found in IL-23 mRNA expression or plasma IL-22, IL-17 levels among E-MDS, L-MDS and controls. CONCLUSIONS: Our data demonstrated that L-MDS cohort had increased frequencies of peripheral Th22 cells and higher mRNA expression levels of IL-6 and TNF-α, indicating that Th22 cells along with Th17 cells or not are involved in the dynamic immune responses of MDS.
Assuntos
Interleucina-17/imunologia , Interleucinas/imunologia , Leucócitos Mononucleares/imunologia , Síndromes Mielodisplásicas/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Adulto , Idoso , Análise de Variância , Primers do DNA/genética , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Humanos , Interferon gama/imunologia , Interleucina-17/metabolismo , Interleucina-23/metabolismo , Interleucina-6/metabolismo , Interleucinas/metabolismo , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Fator de Necrose Tumoral alfa/metabolismo , Interleucina 22RESUMO
Human cytomegalovirus (HCMV) infection is a major cause of morbidity in the recipients of organ transplants and in the congenitally infected infants. HCMV vaccine has emerged as an effective approach to prevent HCMV infection particularly for the development of multiple viral antigens vaccination and human leukocyte antigen (HLA)-restricted polyepitope technology. As the Chinese population makes up more than one fifth of the population worldwide, it is important to develop HCMV vaccines more specific for the Chinese population by targeting Chinese-restricted HLA alleles and antigens. In the present study, we designed a novel chimeric polyepitope vaccine based on the replication-deficient adenovirus Ad5F35, which encodes 83 HCMV T cell epitopes from 15 different HCMV antigens, restricted to 14 HLA I and 7 HLA II alleles that cover 92% of the Chinese population. Our results show that the recombinant adenovirus vaccine Ad5F35-CTL·Th can be efficiently transfected and expressed in peripheral blood mononuclear cells (PBMCs) with little cytopathic activity. Ad5F35-CTL·Th can also be endogenously processed and presented by PBMCs. Ad5F35-CTL·Th-stimulated HCMV-specific cytotoxic T lymphocytes (CTLs) showed strong cytolytic activity against HCMV polyepitope-sensitized target cells. The CTL activity was accompanied by high levels of IFN-γ production after Ad5F35-CTL·Th stimulation. The specificity and vigorous response to the recombinant adenovirus vaccine in vitro makes it a potential candidate to be used for transplantation recipients or congenitally infected infants.
Assuntos
Infecções por Citomegalovirus/prevenção & controle , Vacinas contra Citomegalovirus/imunologia , Citomegalovirus/imunologia , Epitopos de Linfócito T/imunologia , Sequência de Aminoácidos , Povo Asiático/genética , Linhagem Celular , China , Citomegalovirus/genética , Infecções por Citomegalovirus/genética , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/virologia , Vacinas contra Citomegalovirus/genética , Epitopos de Linfócito T/genética , Antígenos HLA/genética , Antígenos HLA/imunologia , Humanos , Dados de Sequência Molecular , Especificidade da Espécie , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologiaRESUMO
OBJECTIVE: To observe the role of interleukin (IL) 21 alone, IL12 alone, and IL21 plus IL12 for inducing the antitumor activity of peripheral blood mononuclear cells (PBMCs) in patients with endometrial cancer. METHODS: PBMCs were isolated from peripheral blood in patients with endometrial cancer in vitro, and kept the culture with low-level IL2. IL2-stimulated PBMCs were cocultured under different conditions (with anti-IL21 antibody, IL21 alone, IL12 alone, or IL21 plus IL12) for 72 h. The cytotoxicity of PBMCs was then examined by lactate dehydrogenase(LDH) released assay. CD4(+) CD25(+) FOXP3(+) regulatory (Treg) cell and CD4(+) IL17A(+) T-helper (Th17) cell proportion were determined with flow cytometry. Cell proliferation and apoptosis were measured by cell counting kit-8(CCK-8)assay and flow cytometry, respectively. RESULTS: In comparison to control group, both IL21 and IL12 significantly enhanced the cytotoxicity of PBMCs. The IL21 plus IL12 group had superior effect to IL21 alone and IL12 alone. IL21 and IL12 significantly decreased the percentages of Treg cells and the rate of PBMCs apoptosis. IL21 or IL12 had no significant effect on the differentiation of Th17 cells and the proliferation of PBMCs. CONCLUSIONS: IL21 and IL12 can enhance the cytotoxicity of PBMCs in patients with endometrial cancer, which can be further strengthened with treatment of IL21 plus IL12. Such effects may be achieved by inhibiting the differentiation of Treg cells and the apoptosis of PBMCs, but not by the differentiation of Th17 cell.
Assuntos
Neoplasias do Endométrio/imunologia , Interleucina-12/farmacologia , Interleucinas/farmacologia , Leucócitos Mononucleares/imunologia , Adulto , Idoso , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Neoplasias do Endométrio/patologia , Feminino , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/patologia , Pessoa de Meia-Idade , Linfócitos T Reguladores/imunologiaRESUMO
OBJECTIVE: To investigate the effect of DNA methylation in combination with histone deacetylase inhibitor on transcription regulation of Ras associated domain family gene 1(RASSF1A) tumor suppressor gene and the molecular biological behaviors in U266 cells. METHODS: The U266 cells were treated with different doses of 5-Aza-2'-deoxycytidine (5-Aza-CdR) and Valproate (VPA) each alone or in combination. Methylation-specific PCR (MSP) was used to detect CpG island methylation in RASSF1A promoter. Quantitative real-time reverse transcription polymerase chain reaction (RQ-PCR) was used to examine the expression of RASSF1A gene in U266 cells. MTT was used for cell proliferation. Cell apoptosis and cell cycle were analyzed by flow cytometry. RESULTS: The methylation of RASSF1A gene promoter was detected in U266 cells, while there was little RASSF1A gene expressing in the control group. The demethylation effect could be detected in the 5-Aza-CdR treated and combined treatment groups but no in the VPA group. The expression level of RASSF1A was induced by 5-Aza-CdR in a concentration-dependent manner while VPA had no such effect. The expression level of RASSF1A mRNA was increased significantly in the combined treatment group. Higher growth inhibition and apoptosis effects were found in 5-Aza-CdR and VPA combination group than that in 5-Aza-CdR or VPA alone group (P < 0.05). After treatment with 5-Aza-CdR or VPA alone for 72 h, more cells were arrested in G(0)/G(1) phase as conpared with control group (P < 0.05), and even more cells were so arrested in combined treatment group (P < 0.05). CONCLUSION: DNA methylation and histone deacetylase inhibitor can synergistically induce demethylation of the RASSF1A gene, re-express RASSF1A gene silenced in U266 cells, inhibit the proliferation of U266 cells and induce cell apoptosis.
Assuntos
Metilação de DNA , Inibidores de Histona Desacetilases , Linhagem Celular Tumoral , Ilhas de CpG , Expressão Gênica , Humanos , Regiões Promotoras GenéticasRESUMO
This study was aimed to investigate the effect of CD44 gene silence on the drug resistance and biologic activity of human multidrug resistant leukemia cell line K562/A02. The oligonucleotides of CD44 gene were designed according to related data of GenBank, double-stranded DNA was produced by annealing, and was inserted into pGCsilencerU6/Neo/GFP vector. The resultant recombinant plasmid pGCsiRNA-CD44 was transfected into K562/A02 cell line. Expressions of CD44, mdr-1 and blc-2 mRNA were assayed by real time RT-PCR. The 50% inhibitory concentration (IC50) of doxorubicin (ADM) for K562/A02 cell line was determined by MTT method. Cell cycle was determined by flow cytometry. The morphology of apoptotic cells was examined by Hochst 33258 staining. The results indicated that the siRNA eukaryotic plasmid directing at CD44 gene could effectively silence the CD44 gene of K562/A02 cells; as compared with control group, the CD44 expression in K562/A02 cells transfected with 4 pGCsiRNA-CD44 plasmids was obviously inhibited, while the inhibition of CD44 expression in cells transfected with siCD44-1 was strongest. After being transfected with pGCsiRNA-CD44, the expression of CD44 mRNA in K562/A02 cells reduced by 64.1% (p<0.05), at the same time the expression of mdr-1 and bcl-2 mRNA in pGCsiRNA-CD44-transfected K562/A02 cells reduced by 25.6% and 50.8% respectively. IC50 of K562/A02 cells after transfection decreased to (8.77+/-1.63) microg/ml and was obviously lower than that of control (17.97+/-1.61) microg/ml (p<0.01). After transfection for 48 hours, the ratio of K562/A02 cells in G0/G1 increased by 10.7%, and the cells displayed karyopyknosis, nuclear margination and apoptotic bodies. It is concluded that the siRNA plasmid specifically targeting CD44 gene can remarkably down-regulate the expression of CD44 gene, inhibit K562/A02 cell proliferation, induce its apoptosis and effectively reverse the multidrug resistance of K562/A02 cells.
Assuntos
Resistência a Múltiplos Medicamentos/genética , Resistencia a Medicamentos Antineoplásicos/genética , Inativação Gênica , Receptores de Hialuronatos/genética , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Vetores Genéticos , Humanos , Células K562 , RNA Interferente PequenoRESUMO
This study was aimed to investigate the common chromosomal aberrations in chronic lymphocytic leukemia (CLL) and to explore the relationship between these chromosomal aberrations and clinical features of CLL. Sequence-specific DNA probes (D13S25, RB1, p53, ATM) and one centromeric probe CSP12 were applied to detect del(13q14), del(17p13), del(11q22-q23) and trisomy 12 by using interphase fluorescence in situ hybridization (I-FISH). 9 CLL patients with negative conventional cytogenetics or without mitotic figure were enrolled in this study. The threshold was established using 10 controls without hematopoietic malignancies. The results indicated that compared with the established threshold, all of the 9 CLL patients showed cytogenetic abnormalities. The detection using p53 and D13S25 showed positive in 7 cases, positive was observed in 5 cases by using ATM and in 4 cases by using both RB1 and CSP12. There was significant correlation between the ATM and the hemoglobin level of the patients. In addition, the elevated probability of gaining bulky lymphadenopathy was found in ATM positive patients. It is concluded that the I-FISH is a more rapid and sensitive technique for analysis of chromosome aberrations in CLL. A large series study with long-term follow-up is needed to reveal the role of cytogenetic abnormalities in the determination of CLL prognosis.
Assuntos
Aberrações Cromossômicas , Hibridização in Situ Fluorescente/métodos , Leucemia Linfocítica Crônica de Células B/genética , Idoso , Idoso de 80 Anos ou mais , Deleção Cromossômica , Análise Citogenética , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To explore the pathogenesis of idiopathic thrombocytopenic purpura (ITP) and improve the differential diagnosis from myelodysplastic syndromes (MDS). METHODS: Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) was performed to detect the point mutation of codon 12,13 in N-ras gene and codon 301, 969 in fms gene in adult and aged ITP and MDS patients. RESULTS: In 25 ITP patients, N-ras mutation and fms mutation were detected in one each (4%). Mutations were found in 3 of 8 MDS patients: two (25%) with N-ras mutation and one (12.5%) with fms mutation. CONCLUSIONS: Patients with N-ras or fms gene mutation diagnosed as MDS rather than ITP.
Assuntos
Genes fms/genética , Genes ras/genética , Síndromes Mielodisplásicas/genética , Púrpura Trombocitopênica Idiopática/genética , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação Puntual , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita SimplesRESUMO
The multiple drug resistance protein (MDR1) is frequently overexpressed in human glioma. The aim of this study is to clone the MDR1 promoter from C6/ADR, construct the double suicide genes expressive vector controlled by MDR1 promoter, and explore its targeted expression in C6/ADR cells. MDR1 promoter from C6/ADR genomic DNA, which was linked with T vector, was amplified by using Polymerase chain reaction (PCR). After cut by NdeI and HindIII, MDR1 promoter was cloned into pcDNA3-TK (thymidine kinase) plasmid. The cytosine deaminase (CD) gene from pcDNA3-CD-TK plasmid was directly cloned into the above vector to construct pcDNA3-MDR1-promoter-CD-TK vector. Then this vector was transfected into C6 and C6/ADR cells respectively by liposome. After selection by G418, the tumor cell lines were stably established. Then these cell lines were examined through PCR and RT-PCR to respectively detect the integration and expression of TK and CD genes. The results showed the length and sequence of MDR1 promoter amplified by PCR were confirmed by DNA sequencing. The pcDNA3-MDR1-promoter-CD-TK expression vectors were constructed successfully. PCR indicated the double suicide genes were integrated into C6 and C6/ADR cells. RT-PCR revealed that CD and TK genes expressed in C6/ADR/CD-TK cells, whereas not in C6/CD-TK cells. In conclusions, construction of expressive vector containing double suicide genes controlled by MDR1 promoter with targeted expression in C6/ADR will provide a sound basis for targeted gene therapy for multidrug resistance (MDR) glioma.
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Genes Transgênicos Suicidas/genética , Glioma/terapia , Regiões Promotoras Genéticas/fisiologia , Animais , Linhagem Celular Tumoral , Citosina Desaminase/genética , Citosina Desaminase/fisiologia , Citometria de Fluxo , Terapia Genética , Vetores Genéticos/fisiologia , Ratos , Timidina Quinase/genética , Timidina Quinase/fisiologia , Transfecção/métodosRESUMO
OBJECTIVE: To explore the role of Notch signaling in human breast cancers, the expression of Notch1 and its ligand JAG1 in human breast cancers and their relationships with clinical stages of breast cancers were analyzed. METHODS: RT-PCR was used to detect the expression of Notch1 and JAG1 in 62 breast cancer specimens and 22 normal breast tissues at the margin of tumor sections, and the statistical difference of expression rates and standardized coefficient between the two groups were analyzed. To compare the expression intensity of Notch1 and JAG1 at different development stages of the illness and at different stages with or without axillary node metastasis. RESULTS: The expression rate and standardized coefficient of Notch1 in human breast cancers were significantly higher than those of normal breast tissues at the margin of tumor sections. The expression rate of JAG1 in human breast cancers was 15%, while JAG1 was not detected in normal breast tissues at the margin of tumor sections. The standardized coefficient of Notch1 in cases with axillary node metastasis was significantly higher than that in cases without axillary node metastasis. The standardized coefficient of Notch1 at stage I was significantly lower than that at stage II, and stage II was significantly higher than stage III. There was no statistically significant difference between stage I and stage III. CONCLUSION: Notch1 and JAG1 are highly expressed in human breast cancers, indicating that the aberrant expression and activation of Notch1 may be related with tumorigenesis of human breast cancer. Notch1 may play different roles at different developmentl stages of human breast cancer.
Assuntos
Neoplasias da Mama/patologia , Proteínas de Ligação ao Cálcio/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas de Membrana/genética , Receptor Notch1/genética , Adulto , Idoso , Mama/metabolismo , Mama/patologia , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Proteína Jagged-1 , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Serrate-Jagged , Transdução de Sinais/genéticaRESUMO
The aim of study was to investigate the killing effect of double suicide gene system mediated by retroviral vector on K562 cells in vivo and ex vivo. CDglyTK gene was transfected into PA317 cells by using lipofectamine. K562 cells were infected with viral supernatant. K562/CDglyTK cells were treated with 5-fluorocytosine (5-FC) and/or ganciclovir (GCV). Mice were randomly divided into three groups: tumor formation, tumor inhibition and tumor therapy. Each mouse was implanted with K562/CDglyTK cells or K562 cells. The results indicated that the killing effect of 5-FC in combination with GCV on K562/CDglyTK was more significant than using 5-FC or GCV alone. In vivo study showed that after being injected subcutaneously with K562 cells and K562/CDglyTK cells, there was not obvious difference in tumor formation rate of mice, 5-FC + GCV could suppress tumor formation of the K562/CDglyTK cells. After being treated with 5-FC and GCV, the median tumor volume of mice implanted with K562/CDglyTK cells decreased obviously, compared with the control group. Their median survival was significantly prolonged. It is concluded that double suicide genes are more effective for killing effect on K562 cells in vivo and in ex vivo. It may be applicable to clinical gene therapy.
Assuntos
Citosina Desaminase/genética , Genes Transgênicos Suicidas/genética , Vetores Genéticos/genética , Proteínas Tirosina Quinases/genética , Flucitosina/farmacologia , Ganciclovir/farmacologia , Terapia Genética , Humanos , Células K562 , Receptores Proteína Tirosina Quinases/biossíntese , Receptores Proteína Tirosina Quinases/genética , Proteínas Recombinantes de Fusão/genética , Recombinação Genética , Retroviridae/genéticaRESUMO
OBJECTIVE: To construct two recombinant plasmids of mdr1 and mcl1 shRNA, and to investigate their reversal effect on drug resistance in K562 adriamycin resistant cell lines (K562/A02). METHODS: Two oligonucleotides of mdr1 and mcl1 gene were designed referring to that of GenBank, double-stranded DNA was derived through annealing, and cloned into pRNAT vector digested by two restricted endoenzymes. K562/A02 cells were transfected with the recombinant plasmids. The mdr1 mRNA expression and its protein product P-glycoprotein (P-gp) were detected by RT-PCR and flow cytometry. The expression of mcl1 gene was detected by RT-PCR. 50% inhibition concentration (IC50) of adriamycin (ADM) on K562/A02 cells was determined by MTT method. Cells apoptosis was analyzed by flow cytometry. RESULTS: Comparing with K562/A02 cells, the shRNA of mdrl or mcl1 gene in vitro can remarkably increase the sensitivity of K562/A02 to adriamycin, down-regulate mdr1 or mcl1 gene expression, increase the K562/A02 cells apoptosis rates induced by adriamycin. Cotransfection of mdrl and mcl1 genes shRNA can also down-regulate the expression of their gene, more remarkably increase the sensitivity and apoptosis of K562/ A02 to adriamycin. CONCLUSION: Transfection of mdrl or mcl1 gene shRNA can promote the sensitivity of K562/A02 to adriamycin and cotransfection of the two shRNA can more remarkably do so. The mel1 gene might be involved in adriamycin resistant in K562/A02 cells.
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Resistência a Múltiplos Medicamentos/genética , Resistencia a Medicamentos Antineoplásicos/genética , Interferência de RNA , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/biossíntese , Apoptose , Citometria de Fluxo , Expressão Gênica , Humanos , Células K562 , Proteína de Sequência 1 de Leucemia de Células Mieloides , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , TransfecçãoRESUMO
OBJECTIVE: To explore the feasibility and efficiency of immunotherapy with dendritic cell (DC) in leukemic mice model after allogeneic bone marrow transplantation (allo-BMT). METHODS: Mature DC were expanded from mice bone marrow mononuclear cells (MNC) by adding mouse granulocyte-macrophage colony stimulating factor (mGM-CSF) and interleukin-4 (mIL-4). Three days later they were pulsed with frozen thawing L7212 leukemia-related antigen. Mice bearing leukemia received allo-BMT at d 0, and then were divided into control group (A), T cells group (B) and DC + T cells group (C) to receive respective immune therapy at d 14. The survival rate, survival time, occurrence of graft-versus-host disease (GVHD), cytotoxicity of spleen cells and serum cytokine level were observed. The survivors in each group were rechallenged with L7212 cells to observe the immune response to the leukemia. RESULTS: Mature DC were successfully induced from bone marrow MNC. In groups B and C, the relapse rates were 30% and 0%, while the long term survival rates after BMT was 30% and 70% respectively. Both of the differences were statistically significant (P < 0.05). However, the incidence of GVHD in these two groups were similar. The mean survival times were (32.95 +/- 13.29) days and (41.15 +/- 13.88) days, respectively (P < 0.01). MTT assay indicated that spleen cells from group C had specific killing activity to L7212 cells. Enzyme-labeled immunosorbent assay (ELISA) showed that the serum IL-2 level in group C was (419.75 +/- 26.66) pg/ml, being significantly higher than that in the other two groups (P < 0.01). When the survivors were rechallenged with L7212 cells, there was difference between the survival rates of groups C and B (85.7% vs 33.3%, P < 0.05). CONCLUSION: Immunotherapy with leukemia related antigen-pulsed DC in combination with donor lymphocyte infusions is an effective approach to reinforce GVL effect and decrease relapse after allo-BMT.
Assuntos
Células Dendríticas/imunologia , Imunoterapia , Leucemia Experimental/terapia , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/imunologia , Transplante de Medula Óssea , Vacinas Anticâncer/imunologia , Diferenciação Celular , Feminino , Efeito Enxerto vs Leucemia , Leucemia Experimental/imunologia , Leucemia Experimental/cirurgia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Taxa de Sobrevida , Transplante HomólogoRESUMO
OBJECTIVE: To investigate the effect on apoptosis of HeLa cells by transfecting c-myc antisense oligonucleotides and seek a new method to enhance radiosensitivity of tumor cells. METHODS: Immunohistochemistry staining and RT-PCR were conducted to identify the effect of ASODN. Giemsa staining, flow cytometry (FCM) and DNA ladder were performed to detect the apoptosis of HeLa cells. RESULTS: After transfection of ASODN (c-myc), the levels of both c-myc mRNA and C-MYC protein expression were reduced (P < 0.05). Giemsa staining demonstrated apoptosis-bodies on the c-myc ASODN-transfected cells. DNA ladder presented the typical ladder of apoptosis. The apoptosis rate of HeLa cells transfected with c-myc ASODN was (10.29 +/- 0.66)%, transfected c-myc ASODN combined irradiation was (16.83 +/- 0.57)%, which were much higher than that of control group (1.79 +/- 0.19)% (P < 0.05). CONCLUSION: The c-myc ASODN could effectively down-regulate the expression of c-myc; furthermore, transfection of c-myc ASODN could more effectively induce apoptosis of HeLa cells which subsequently enhanced radiosensitivity of HeLa cells.
Assuntos
Apoptose/genética , Oligonucleotídeos Antissenso/genética , Proteínas Proto-Oncogênicas c-myc/genética , Apoptose/efeitos da radiação , Feminino , Citometria de Fluxo , Células HeLa , Humanos , Imuno-Histoquímica , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , TransfecçãoRESUMO
OBJECTIVES: To make humanized monoclonal antibodies by phage surface display technology, we screened out the specific anti-platelet glycoproteins (GPs) IgG antibody from patients with chronic idiopathic thrombocytopenic purpura (ITP), which can inhibit platelet aggregation. METHODS: We studied plasmas from 68 patients with ITP for the presence of IgG antibodies specific for GPIIb/IIIa and/or GPIb/IX using modified monoclonal antibody immobilization of platelet antigen assays. The IgG antibody and its F(ab')(2) fragments of the positive plasmas which could inhibit platelet aggregation function were prepared and purified. Their immunoreactivity to platelet GPs and effects on platelet function were further analyzed. RESULTS: GPIIb/IIIa- and GPIb/IX-specific antibodies were found in 21 and 19 patients, respectively. Six of them had antibodies against both GP complexes. Among the 34 positive plasmas, four with positive anti-GPIIb/IIIa autoantibody showed significant inhibition of platelet aggregation induced by adenosine diphosphate (ADP), whereas one with GPIb/IX-specific antibody inhibited ristocetin-induced platelet aggregation. The purified IgG and its F(ab')(2) fragments from two patients not only retained the ability to bind to platelet GPs but also impaired the in vitro ADP-induced platelet aggregation. CONCLUSIONS: F(ab')(2) portion of the IgG is a functional fragment, which is responsible for the autoantibody interaction with platelet GPs in ITP, and some of them also affect platelet function, which can be used to develop completely humanized anti-GPIIb/IIIa small molecular phage antibody.