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1.
Erythropoietin can promote erythroid progenitor survival by repressing apoptosis through Bcl-XL and Bcl-2 总被引:15,自引:9,他引:15
Erythropoietin (Epo), the hormone that is the principal regulator of red blood cell production, interacts with high-affinity receptors on the surface of erythroid progenitor cells and maintains their survival. Epo has been shown to promote cell viability by repressing apoptosis; however, the molecular mechanism involved is unclear. In the present studies we have examined whether Epo acts as a survival factor through the regulation of the bcl-2 family of apoptosis-regulatory genes. We addressed this issue in HCD-57, a murine erythroid progenitor cell line that requires Epo for proliferation and survival. When HCD-57 cells were cultured in the absence of Epo, Bcl-2 and Bcl-XL but not Bax were downregulated, and the cells underwent apoptotic cell death. HCD-57 cells infected with a retroviral vector encoding human Bcl-XL or Bcl-2 rapidly stopped proliferating but remained viable in the absence of Epo. Furthermore, endogenous levels of bcl-2 and bcl-XL were downregulated after Epo withdrawal in HCD-57 cells that remained viable through ectopic expression of human Bcl-XL, further indicating that Epo specifically maintains the expression of bcl-2 and bcl-XL. We also show that HCD-57 rescued from apoptosis by ectopic expression of Bcl-XL can undergo erythroid differentiation in the absence of Epo, demonstrating that a survival signal but not Epo itself is necessary for erythroid differentiation of HCD-57 progenitor cells. Thus, we propose a model whereby Epo functions as a survival factor by repressing apoptosis through Bcl-XL and Bcl-2 during proliferation and differentiation of erythroid progenitors. 相似文献
2.
Bcl-2 oncoprotein blocks chemotherapy-induced apoptosis in a human leukemia cell line 总被引:83,自引:6,他引:83
Previous studies have shown that the bcl-2 gene encodes a mitochondrial protein that contributes to neoplastic cell expansion primarily by promoting cell survival through interference with "programmed cell death" (PCD), also termed "apoptosis." Because many chemotherapeutic drugs are capable of initiating pathways leading to apoptosis, we determined whether deregulated bcl-2 expression could render cells resistant to several drugs commonly used in the treatment of non- Hodgkin's lymphomas, including dexamethasone (DEX), methotrexate (MTX), 1-beta-D-arabinofuranosyl-cytosine (Ara-C), etoposide (VP-16), vincristine (VC), cisplatin (CP), and hydroperoxycyclophosphamide (4- HC). For these experiments, we achieved high levels of p26-Bcl-2 protein production in a human pre-B-cell leukemia line 697 by stable infection with a recombinant bcl-2-containing retrovirus and then compared these cells with control virus-infected 697 cells. Control 697 cells were induced to undergo apoptosis by all drugs tested as defined by DNA degradation into oligonucleosomal-length fragments, cell shrinkage, and subsequent cell death. In contrast, 697 cells with elevated Bcl-2 protein levels exhibited strikingly prolonged cell survival and markedly reduced DNA fragmentation when cultured in the presence of these antineoplastic agents. Although high levels of Bcl-2 protein protected 697 cells from the acute cytotoxic effects of DEX and the other drugs tested, Bcl-2 did not prevent these drugs from suppressing the proliferation of 697 cells. However, when 697 cells were treated with DEX or MTX for 3 days, then washed and cultured in semisolid media without drugs, bcl-2-virus-infected cells gave rise to colonies at much higher frequencies than 697 cells stably infected with control virus. These results indicate that by protecting 697 leukemic cells from the acute cytotoxicity of DEX and some other chemotherapeutic drugs, high levels of p26-Bcl-2 can create the opportunity for re-initiation of cell growth when drugs are withdrawn. The findings may be relevant to clinical correlative studies of non- Hodgkin's lymphoma patients that have found an association between worse prognosis and bcl-2 gene rearrangements or t[14;18] translocations. 相似文献
3.
J Zhang N Alter J C Reed C Borner L M Obeid Y A Hannun 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(11):5325-5328
Ceramide, a product of sphingomyelin turn-over, has been proposed as a novel lipid second messenger with specific roles in mediating antiproliferative responses including apoptosis and cell cycle arrest. In this study, we examine the relationship between the ceramide-mediated pathway of growth suppression and the bcl-2 protooncogene. In ALL-697 leukemia cells, the addition of the chemotherapeutic agent vincristine resulted in a time-dependent growth suppression characterized by marked apoptosis. The effects of vincristine on cell death were preceded by a prolonged and sustained accumulation of endogenous ceramide levels reaching -10.4 pmol ceramide/nmol phospholipids at 12 hr following the addition of vincristine--an increase of 220% over vehicle-treated cells. Overexpression of bcl-2 resulted in near total protection of cell death in response to vincristine. However, the ceramide response to vincristine was not modulated by overexpression of bcl-2, indicating that bcl-2 does not interfere with ceramide formation. Overexpression of bcl-2 prevented apoptosis in response to ceramide, suggesting that bcl-2 acts at a point downstream of ceramide. On the other hand, bcl-2 did not interfere with the ability of ceramide to activate the retinoblastoma gene product or to induce cell cycle arrest, suggesting that the effects of ceramide on cell cycle arrest can be dissociated from the effects on apoptosis. These studies suggest that ceramide and bcl-2 partake in a common pathway of cell regulation. The results also cast ceramide as a gauge of cell injury rather than an "executor" of cell death with clearly dissociable biological outcomes of its action depending on downstream factors. 相似文献
4.
5.
Apoptosis induced by erythroid differentiation of human leukemia cell lines is inhibited by Bcl-XL 总被引:7,自引:3,他引:7
The induction of tumor cell differentiation represents an attractive strategy for the treatment of a wide range of malignancies. Differentiation of HL-60 promyelocytic leukemia cells towards neutrophils or monocytes has been shown to induce apoptotic cell death, which is inhibited by bcl-2 over-expression. However, the role of the bcl-2 gene family during erythroid differentiation of human leukemia cells remains unknown. We found that human erythroleukemia (HEL) and K562, two leukemia cell lines that undergo erythroid differentiation do not express Bcl-2, but express Bcl-XL, a related protein that functions as an inhibitor of apoptosis. Differentiation of HEL or K562 cells with inducers of erythroid differentiation (hemin, retinoic acid, or transforming growth factor-beta) was accompanied by progressive cell death and degradation of genomic DNA into oligonucleosomal fragments. The loss of cellular viability was associated with downregulation of bcl-xL mRNA and protein. In contrast, the levels of Bax, another Bcl-2 family member implicated in apoptosis remained unaltered. Constitutive expression of Bcl-XL by gene transfer inhibited apoptosis triggered by erythroid differentiation of HEL K562 cells. Yet, Bcl-XL did not alter the expression of epsilon-globin, which is induced during erythoid differentiation of HEL and K562 cells, arguing that apoptosis and differentiation can be uncoupled by Bcl-XL. These results indicate that Bcl-XL acts as an antiapoptosis protein in leukemia cells that undergo erythroid differentiation and that downregulation of bcl-x is a component of the apoptotic response that is coupled to differentiation in human leukemia cells. 相似文献
6.
An essential role for Bruton''s [corrected] tyrosine kinase in the regulation of B-cell apoptosis. 总被引:2,自引:0,他引:2
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J S Anderson M Teutsch Z Dong H H Wortis 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(20):10966-10971
Mutations of the Bruton's tyrosine kinase (btk) gene cause X-linked agammaglobulinemia (XLA) in humans and X-linked immune deficiency (Xid) in mice. To establish the BTK role in B-cell activation we examined the responses of wild-type and Xid B cells to stimulation through surface IgM and CD40, the transducers of thymus independent-type 2 and thymus-dependent activation, respectively. Wild-type BTK was necessary for proliferation induced by soluble anti-IgM (a prototype for thymus independent-type 2 antigen), but not for responses to soluble CD40 ligand (CD40L, the B-cell activating ligand expressed on T-helper cells). In the absence of wild-type BTK, B cells underwent apoptotic death after stimulation with anti-IgM. In the presence of wild-type but not mutated BTK, anti-IgM stimulation reduced apoptotic cell death. In contrast, CD40L increased viability of both wild-type and Xid B cells. Importantly, viability after stimulation correlated with the induced expression of bcl-XL. In fresh ex vivo small resting B cells from wild-type mice there was only barely detectable bcl-XL protein, but there was more in the larger, low-density ("activated") splenic B cells and peritoneal B cells. In vitro Bcl-XL induction following ligation of sIgM-required BTK, was cyclosporin A (CsA)-sensitive and dependent on extracellular Ca2+. CD40-mediated induction of bcl-x required neither wild-type BTK nor extracellular Ca2+ and was insensitive to CsA. These results indicate that BTK lies upstream of bcl-XL in the sIgM but not the CD40 activation pathway. bcl-XL is the first induced protein to be placed downstream of BTK. 相似文献
7.
We have explored a dose reduction of bleomycin in combination with etoposide and cisplatin in the treatment of a good-prognosis subgroup of patients with nonseminomatous germ cell tumors. Twenty-two patients were treated with etoposide, cisplatin, and low-dose bleomycin. All patients achieved complete remission, but four relapsed. Three patients achieved long-term remission after salvage therapy. The disease-free survival rate of 82% (18 of 22 patients) at a median follow-up of 24 months (range, 17-33) was significantly worse compared to the 99% disease-free survival rate in 91 patients receiving full-dose bleomycin, etoposide, and cisplatin. These results are similar to a previously reported 82% disease-free survival rate of 17 patients treated with etoposide and cisplatin alone. The combined results of the 82% disease-free survival rate in the total group of 39 patients treated with etoposide and cisplatin and etoposide, cisplatin, and low-dose bleomycin suggest that the reduced bleomycin regimens in their present schedule constitute inadequate therapy. 相似文献
8.
Dissection of the genetic programs of p53-mediated G1 growth arrest and apoptosis: blocking p53-induced apoptosis unmasks G1 arrest 总被引:9,自引:0,他引:9
Guillouf C; Grana X; Selvakumaran M; De Luca A; Giordano A; Hoffman B; Liebermann DA 《Blood》1995,85(10):2691-2698
Employing the myeloblastic leukemia M1 cell line, which does not express endogenous p53, and genetically engineered variants, it was recently shown that activation of p53, using a p53 temperature- sensitive mutant transgene (p53ts), resulted in rapid apoptosis that was delayed by high level ectopic expression of bcl-2. In this report, advantage has been taken of these M1 variants to investigate the relationship between p53-mediated G1 arrest and apoptosis. Flow cytometric cell cycle analysis has provided evidence that activation of wild-type (wt) p53 function in M1 cells resulted in the induction of G1 growth arrest; this was clearly seen in the M1p53/bcl-2 cells because of the delay in apoptosis that unmasked p53-induced G1 growth arrest. This finding was further corroborated at the molecular level by analysis of the expression and function of key cell cycle regulatory genes in M1p53 versus M1p53/bcl-2 cells after the activation of wt p53 function; events that take place at early times during the p53-induced G1 arrest occur in both the M1p53 and the M1p53/bcl-2 cells, whereas later events occur only in the M1p53/bcl-2 cells, which undergo delayed apoptosis, thereby allowing the cells to complete G1 arrest. Finally, it was observed that a spectrum of p53 target genes implicated in p53- induced growth suppression and apoptosis were similarly regulated, either induced (gadd45, waf1, mdm2, and bax) or suppressed (c-myc and bcl-2), after activation of wt p53 function in M1p53 and M1p53/bcl-2 cells. Taken together, these findings show that wt p53 can simultaneously induce the genetic programs of both G1 growth arrest and apoptosis within the same cell type, in which the genetic program of cell death can proceed in either G1-arrested (M1p53/bcl-2) or cycling (M1p53) cells. These findings increase our understanding of the functions of p53 as a tumor suppressor and how alterations in these functions could contribute to malignancy. 相似文献
9.
AIM: To examine the ability of cyclin-dependent kinase inhibitor (CDKI) roscovitine (Rosco) to enhance the antitumor effects of conventional chemotherapeutic agents acting by different mechanisms against human colorectal cancer. METHODS: Human colorectal cancer cells were treated, individually and in combination, with Rosco, taxol, 5-Fluorouracil (5-FU), doxorubicine or vinblastine. The antiproliferative effects and the type of interaction of Rosco with tested chemotherapeutic drugs were determined. Cell cycle alterations were investigated by fluorescence-activated cell sorter FACS analysis. Apoptosis was determined by DNA fragmentation assay. RESULTS: Rosco inhibited the proliferation of tumor cells in a time-and dose-dependent manner. The efficacies of all tested chemotherapeutic drugs were markedly enhanced 3.0-8.42 × 10^3 and 130-5.28 × 10^3 fold in combination with 5 and 10 μg/mL Rosco, respectively. The combination of Rosco and chemotherapeutic drugs inhibited the growth of human colorectal cancer cells in an additive or synergistic fashion, and in a time and dose dependent manner. Rosco induced apoptosis and synergized with tested chemotherapeutic drugs to induce efficient apoptosis in human colorectal cancer cells. Sequential, inverted sequential and simultaneous treatment of cancer cells with combinations of chemotherapeutic drugs and Rosco arrested the growth of human colorectal cancer cells at various phases of the cell cycle as follows: Taxol/Rosco (G2/M-and S-phases), 5-FU/Rosco (S-phase), Dox/Rosco (S-phase) and Vinb/Rosco (G2/M-and S-phases). CONCLUSION: Since the eff icacy of many anticancer drugs depends on their ability to induce apoptotic cell death, modulation of this parameter by cell cycle inhibi-tors may provide a novel chemo-preventive and chemo-therapeutic strategy for human colorectal cancer. 相似文献
10.
Wanner K Hipp S Oelsner M Ringshausen I Bogner C Peschel C Decker T 《British journal of haematology》2006,134(5):475-484
Diffuse large B-cell lymphoma (DLBCL) is a common lymphoma entity. Although a significant amount of DLBCL patients can be cured with modern chemotherapeutic regimens, a substantial proportion of patients die because of progressive disease. Therefore, new therapeutic strategies are clearly needed. Inhibitors of mTOR [mammalian target of rapamycin (Rap)] represent a new class of antiproliferative drugs with applications as immunosuppressive and anticancer agents. Extensive safety data exist on the mTOR inhibitor RAD001, which is already approved as an immunosuppressant in organ transplant recipients. Rap and RAD001 inhibited cell cycle progression in DLBCL cells by inducing a G1 arrest without inducing apoptosis. Phosphorylation of the main targets of mTOR, p70 s6 kinase and 4-EBP-1 was reduced in cells cultured in the presence of RAD001. Cell cycle arrest was accompanied by reduced phosphorylation of the retinoblastoma protein (RB) as well as reduced expression of cyclin D3 and A in all cell lines. Although the effect of the chemotherapeutic agent vincristine (vin) was not enhanced by RAD001, rituximab-induced cytotoxicity was augmented in the rituximab-sensitive cell lines. mTOR inhibition is a promising therapeutic strategy in DLBCL by inducing a G1 arrest and augments rituximab-induced cytotoxicity. Therefore, combination of these drugs might be an interesting new therapeutic approach in DLBCL patients. 相似文献
11.
OBJECTIVE: To study the effect of antisense oligodeoxyribonucleotide (ODN) to apoptotic suppress gene bcl-2 on apoptosis of lung carcinoma cells induced by cisplatin. METHODS: The lung carcinoma cells expressing bcl-2 were chosen to participate in this experiment. Cultured cells were divided into 7 groups: ODN, nonsense, ODN + cisplatin, nonsense + cisplatin, cisplatin, lipofectin and control. Bcl-2 antisense or nonsense mixed with lipofectin was added into above corresponding cultured cells. After cultured for 6 hours, cisplatin was added into corresponding groups. The cells were cultured again for 16 hours. And then, the cells were smeared on slides. Apoptotic cells were labeled with TdT-mediated dUTP nick end labeling (TUNEL) method on cell smears. Apoptotic index (AI) was counted to show the percentage of apoptotic cancer cells. The immunocytochemistry was used to detect the expression of bcl-2 in carcinoma cells. RESULTS: The bcl-2 expression of cancer cell in ODN group was significantly decreased compared to the control and nonsense groups. The AI of ODN + cisplatin group was 16.4 +/- 1.7, cisplatin group 4.1 +/- 0.8, antisense group 5.9 +/- 0.2, nonsense group 3.3 +/- 0.7, nonsense + cisplatin 7.6 +/- 1.1, lipofectin 5.1 +/- 0.9, control group 3.6 +/- 0.6. The AI of antisense + cisplatin group was significantly higher than that of other groups. CONCLUSION: Antisense oligodeoxyribonucleotide to bcl-2 can inhibit significantly the expression of bcl-2 of lung cancer cells and increase apoptosis of cancer cells induced by cisplatin. 相似文献
12.
Identification and functional significance of genes regulated by structurally different histone deacetylase inhibitors 总被引:13,自引:0,他引:13
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Peart MJ Smyth GK van Laar RK Bowtell DD Richon VM Marks PA Holloway AJ Johnstone RW 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(10):3697-3702
13.
Yunkyung Hong Jinyoung Won Youngjeon Lee Seunghoon Lee Kanghui Park Kyu‐Tae Chang Yonggeun Hong 《Journal of pineal research》2014,56(3):264-274
In Asia, the incidence of colorectal cancer has been increasing gradually due to a more Westernized lifestyle. The aim of study is to determine the interaction between melatonin‐induced cell death and cellular senescence. We treated HCT116 human colorectal adenocarcinoma cells with 10 μm melatonin and determined the levels of cell death‐related proteins and evaluated cell cycle kinetics. The plasma membrane melatonin receptor, MT1, was significantly decreased by melatonin in a time‐dependent manner, whereas the nuclear receptor, RORα, was increased only after 12 hr treatment. HCT116 cells, which upregulated both pro‐apoptotic Bax and anti‐apoptotic Bcl‐xL in the early response to melatonin treatment, activated autophagic as well as apoptotic machinery within 18 hr. Melatonin decreased the S‐phase population of the cells to 57% of the control at 48 hr, which was concomitant with a reduction in BrdU‐positive cells in the melatonin‐treated cell population. We found not only marked attenuation of E‐ and A‐type cyclins, but also increased expression of p16 and p‐p21. Compared to the cardiotoxicity of Trichostatin A in vitro, single or cumulative melatonin treatment induced insignificant detrimental effects on neonatal cardiomyocytes. We found that 10 μm melatonin activated cell death programs early and induced G1‐phase arrest at the advanced phase. Therefore, we suggest that melatonin is a potential chemotherapeutic agent for treatment of colon cancer, the effects of which are mediated by regulation of both cell death and senescence in cancerous cells with minimized cardiotoxicity. 相似文献
14.
Cos S Mediavilla MD Fernández R González-Lamuño D Sánchez-Barceló EJ 《Journal of pineal research》2002,32(2):90-96
Melatonin inhibits proliferation of the estrogen-responsive MCF-7 human breast cancer cells. The objective of this work was to assess whether melatonin not only regulates MCF-7 cell proliferation but also induces apoptosis. In this experiment we used 1,25-dihydroxycholecalciferol (D3) as a positive control because it inhibits MCF-7 cell proliferation and induces apoptosis. MCF-7 cells were cultured with either I nM melatonin, 100 nM D3 or its diluent to determine their effects on cell proliferation, cell viability, cell-cycle phase distribution, population of apoptotic cells, and expression of p53, p21WAF1, bcl-2, bcl-X(L) and bax proteins. After 24 or 48 hr of incubation, both melatonin and D3-treatment significantly decreased the number of viable cells in relation to the controls, although no differences in cell viability were observed between the treatments. The incidence of apoptosis, measured as the population of cells falling in the sub-G1 region of the DNA histogram, or by the TUNEL reaction, was similar in melatonin-treated and control cells whereas, as expected, apoptosis was higher among cells treated with D3 than in controls. The expression of p53 and p21WAF1 proteins significantly increased after 24 or 48 hr of incubation with either melatonin or D3. No significant changes in bcl-2, bcl-XL and bax mRNAs were detected after treatment with melatonin whereas in D3-treated cells, a significant drop in bcl-XL was observed. These data support the hypothesis that melatonin reduces MCF-7 cell proliferation by modulating cell-cycle length through the control of the p53-p21 pathway, but without clearly inducing apoptosis. 相似文献
15.
To evaluate the utility of nude mouse xenografts as preclinical drug screens, the activity of ten established chemotherapeutic agents was evaluated against seven melanoma and three ovarian carcinoma xenografts. Xenografts were established using primary explants from patients who had not received chemotherapy and serially passaged as sc tumors in nude mice. In vivo drug activities for dactinomycin, carmustine, vinblastine, melphalan, amsacrine, cisplatin, bleomycin, mitomycin, doxorubicin, and etoposide were evaluated by 4 weekly ip injections of 10% less than LD10 doses. Plots of relative tumor growth versus time were nearly log-linear. Analysis of in vivo activity was performed using percent control growth (treated/control tumor volume) and by calculation of a novel growth delay index obtained by fitting growth curves to a quadratic regression model. Both modes of data analysis identified alkylating agents (melphalan, carmustine, and mitomycin) as the most active drugs against human melanomas. Melphalan, mitomycin, and cisplatin showed the greatest activity against ovarian xenografts. However, complete tumor regressions were noted only with melphalan, mitomycin, and cisplatin against a single ovarian tumor xenograft. Correlation analysis suggested xenograft tumor growth rate was an important determinant of drug response. These results suggest that preclinical, new-drug screening with melanoma xenografts would identify drugs such as alkylating agents as active, and may not provide an advantage over murine leukemia screens. However, screening with ovarian xenografts may more closely reflect clinical drug activity. Criteria for detecting active drugs in such systems are discussed. 相似文献
16.
Uguz AC Cig B Espino J Bejarano I Naziroglu M Rodríguez AB Pariente JA 《Journal of pineal research》2012,53(1):91-98
Abstract: Melatonin has antitumor activity via several mechanisms including its antiproliferative and proapoptotic effects in addition to its potent antioxidant action. Thus, melatonin has proven useful in the treatment of tumors in association with chemotherapeutic drugs. This study was performed to evaluate the effect of melatonin on the cytotoxicity and apoptosis induced by three different chemotherapeutic agents, namely 5‐fluorouracil (5‐FU), cisplatin, and doxorubicin in the rat pancreatic tumor cell line AR42J. We found that both melatonin and the three chemotherapeutic drugs induce a time‐dependent decrease in AR42J cell viability, reaching the highest cytotoxic effect after 48 hr of incubation. Furthermore, melatonin significantly augmented the cytotoxicity of the chemotherapeutic agents. Consistently, cotreatment of AR42J cells with each of the chemotherapeutic agents in the presence of melatonin increased the population of apoptotic cells, elevated mitochondrial membrane depolarization, and augmented intracellular reactive oxygen species (ROS) production compared to treatment with each chemotherapeutic agent alone. These results provide evidence that in vitro melatonin enhances chemotherapy‐induced cytotoxicity and apoptosis in rat pancreatic tumor AR42J cells and, therefore, melatonin may be potentially applied to pancreatic tumor treatment as a powerful synergistic agent in combination with chemotherapeutic drugs. 相似文献
17.
Deguelin, A PI3K/AKT inhibitor, enhances chemosensitivity of leukaemia cells with an active PI3K/AKT pathway 总被引:2,自引:0,他引:2
Bortul R Tazzari PL Billi AM Tabellini G Mantovani I Cappellini A Grafone T Martinelli G Conte R Martelli AM 《British journal of haematology》2005,129(5):677-686
Activation of the phosphoinositide 3 kinase (PI3K)/Akt signalling pathway has been linked with resistance to chemotherapeutic drugs, and its downregulation, by means of PI3K inhibitors, lowers resistance to various types of therapy in tumour cell lines. Recently, it has been reported that deguelin, a naturally occurring rotenoid, is a powerful inhibitor of PI3K. We investigated whether or not deguelin could enhance the sensitivity to chemotherapeutic drugs of human U937 leukaemia cells and acute myeloid leukaemia (AML) blasts with an activated PI3K/Akt network. Deguelin (10 nmol/l) induced S phase arrest with interference of progression to G2/M, and at 100 nmol/l significantly increased apoptotic cell death of U937. At 10-100 nmol/l concentrations, deguelin downregulated Akt phosphorylation of leukaemia cells and markedly increased sensitivity of U937 cells to etoposide or cytarabine. A 10 nmol/l concentration of deguelin did not negatively affect the survival rate of human cord blood CD34+ cells, whereas it increased sensitivity of AML blasts to cytarabine. Deguelin was less toxic than wortmannin on erythropoietin- and stem cell factor-induced erythropoiesis from CD34+ progenitor cells. Overall, our results indicate that deguelin might be used in the future for increasing sensitivity to therapeutic treatments of leukaemia cells with an active PI3K/Akt signalling network. 相似文献
18.
Three patients with endodermal sinus tumor of the mediastinum and two with endodermal sinus tumor mixed with other histologies were treated with CEBA (cisplatin, etoposide, bleomycin, and doxorubicin [Adriamycin]) and by cytoreductive surgery. Three patients treated with CEBA followed by surgery achieved a complete remission and remain free of disease at 36+, 35+, and 28+ months, respectively, from diagnosis. Two patients were treated initially with vinblastine, bleomycin, cisplatin, and surgery, and neither achieved a complete remission. Both then received CEBA, and one achieved a complete remission (duration 47 + months). Bone marrow toxicity from CEBA was severe, abrupt, and cumulative. All patients experienced neutropenic fever, anemia, and thrombocytopenia requiring platelet transfusions. The CEBA followed by vigorous cytoreductive surgery is effective treatment for germ cell tumors of the medastinum containing endodermal sinus tumor elements. 相似文献
19.
20.
Bone metastasis is usually a late manifestation in patients with germ cell tumors and a poor prognosis site. We report a case of 29-year-old man with a nonseminomatous germ cell tumor who presented with a single metastatic site in a vertebrae with spinal compression. He was treated with a left orchiectomy and four cycles of chemotherapy containing bleomycin, etoposide, and cisplatin. He attained complete remission. 相似文献