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1.
Zhonghua Xue Ye Xue Za Zhi ; 45(1): 35-40, 2024 Jan 14.
Artigo em Chinês | MEDLINE | ID: mdl-38527836

RESUMO

Objective: To evaluate the efficacy and safety of chimeric antigen receptor T-cell (CAR-T) therapy followed by allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with Ph-like acute lymphoblastic leukemia (Ph-ALL) . Methods: Patients with Ph-ALL who underwent CAR-T therapy followed by allo-HSCT from March 2018 to August 2023 at the First Affiliated Hospital of Soochow University were included, and their clinical data were retrospectively analyzed. Results: Of the 21 patients, 14 were male and 7 were female. The median age at the time of CAR-T therapy was 22 (6-50) years. Seven patients had ABL1-like rearrangements, and 14 had JAK-STAT rearrangements. Prior to CAR-T therapy, 12 patients experienced hematologic relapse; 7 were multiparameter flow cytometry minimal residual disease (MFC-MRD) -positive and 2 were MFC-MRD-negative. CAR-T cells were derived from patients' autologous lymphocytes. Nine patients were treated with CD19 CAR-T cells, and 12 were treated with CD19/CD22 CAR-T cells. After assessment on day 28 after CAR-T therapy, 95.2% of the patients achieved complete remission, with an MRD-negative remission rate of 75%. Nineteen patients developed grade 0-2 cytokine release syndrome (CRS) and 2 patients suffered grade 3 CRS, all cases of which resolved after treatment. All patients underwent allo-HSCT after CAR-T therapy. The median time from CAR-T therapy to allo-HSCT was 63 (38-114) days. Five patients experienced relapse after CAR-T therapy, including four with hematologic relapse and one with molecular relapse. The 3-year overall survival (OS) rates in the ABL1 and JAK-STAT groups were (83.3±15.2) % and (66.6±17.2) %, respectively (P=0.68) . The 3-year relapse-free survival (RFS) rates were (50.0±20.4) % and (55.6±15.4) % in the ABL1 and JAK-STAT groups, respectively. There was no significant difference in 3-year OS or RFS between the two groups. Conclusions: CAR-T therapy followed by allo-HSCT leads to rapid remission in most patients with Ph-ALL and prolongs leukemia-free survival.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Receptores de Antígenos Quiméricos , Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Imunoterapia Adotiva , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Doença Aguda , Recidiva , Antígenos CD19
8.
Zhonghua Xue Ye Xue Za Zhi ; 39(12): 983-988, 2018 Dec 14.
Artigo em Chinês | MEDLINE | ID: mdl-30612398

RESUMO

Objective: To investigate the survival and prognostic factors of allogeneic hematopoietic stem-cell transplantation (allo-HSCT) for patients with myeloid neoplasms and RUNX1 mutations. Methods: From July 2014 to April 2018, the clinical data of forty-two AML/MDS patients with RUNX1 mutations in the First Affiliated Hospital of Soochow University were retrospectively analyzed. The clinical characteristic features and distribution of the mutations frequently observed with RUNX1 mutations were summarized, the prognosis of allo-HSCT for these patients was also analyzed. Results: Among 42 AML/MDS patients with RUNX1 mutations, 27 were male, 15 were female. The median age was 43.5 (16-68) years old. There are 31 patients in allo-HSCT group and 11 patients in chemotherapy group. RUNX1 mutations co-occurred with many other gene mutations, the most frequent mutations were FLT3 (26.2%, 11/42) . Interestingly, FLT3 mutations only occurred in AML patients compared with MDS patients (P=0.014) . ASXL1 (25%, 3/12) mutations were observed as the most frequent co-mutations in MDS patients. One-year overall survival (OS) , disease-free survival (DFS) of allo-HSCT and chemotherapy patients were (70.6±9.0) %, (61.0±9.4) % and (34.4±16.7) %, (22.4±15.3) %, respectively. When OS and DFS between allo-HSCT and chemotherapy patients were compared, significant differences (χ(2)=4.843, 4.320, P<0.05) were showed. In univariate analysis, transplant age >45 years was a negative effect for OS [HR=4.819 (95% CI 1.145-20.283) , P=0.032] and DFS [HR=5.945 (95% CI 1.715-20.604) , P=0.005]. Also, complex chromosome karyotype abnormality was a negative effect for OS [HR=5.572 (95%CI 1.104-28.113) , P=0.038]. Conclusion: Transplant age (>45 years) and complex chromosome karyotype abnormality were negative prognostic factors in allo-HSCT for myeloid neoplasms patients with RUNX1 mutations.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/genética , Leucemia Mieloide Aguda/genética , Mutação , Adulto , Idoso , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Transplante Homólogo
9.
Zhonghua Xue Ye Xue Za Zhi ; 38(1): 22-27, 2017 Jan 14.
Artigo em Chinês | MEDLINE | ID: mdl-28219220

RESUMO

Objective: To investigate the overexpression frequencies of BRE and EVI1, the correlation between BRE and EVI1 expressions and their possible clinical implications in 11q23/MLL rearrangement acute leukemia. Methods: Cytogenetic examination of bone marrow cells was performed by short-term culture method. R-banding technique was used for karyotype analysis. 47 patients were detected by interphase fluorescence in situ hybridization (FISH) with dual-color break apart MLL probe. The expressions of EVI1 and BRE genes were detected by real time quantitative reverse transcription polymerase chain reaction (RQ-PCR) . The correlation and prognostic significance were statistically tested. Results: 11q23/MLL rearrangements were confirmed by karyotyping and FISH, respectively in 47 patients. According to immunophenotypic analyses of 37 patients, 5 patients showed positive for CD19, CD79a or CD10, 1 for CD7; the others for CD33, CD13, CD14 and CD15, and 16 of them for CD34. Of the 47 patients, 18 patients showed EVI1 overexpression and most of them presented with t (6;11) and M(4)/M(5). The EVI1 expression was high in t (6;11) or t (9;11) subgroup comparable with levels observed in normal subgroup (P=0.038, 0.022, respectively) . 15 patients showed high BRE expression, and most of them presented with t (9;11) and M(4)/M(5). High BRE expression was found in t (4;11) , t (6;11) , t (9;11) and t (11;19) subgroups, respectively by comparing with normal subgroup. The BRE expression was higher in t (4;11) (P=0.004) or t (9;11) (P=0.012) subgroup than in t (6;11) subgroup. Patients with EVI1 overexpression had a short survival compared with those with low EVI1 expression (P=0.049) and it also did in t (9;11) subgroup (P=0.024) . Patients with t (9;11) and high BRE expression had a long survival compared with those with t (9;11) and low BRE expression (P=0.024) . Conclusion: The EVI1 overexpression was significantly frequent in acute leukemia patients with 11q23/MLL rearranged, especially within t (6;11) subgroup and M(4)/M(5), which was associated with an inferior outcome. High BRE expression was observed frequently in 11q23/MLL-rearranged acute leukemia especially within t (9;11) subgroup and M(5).


Assuntos
Cromossomos Humanos Par 11 , Leucemia Mieloide Aguda , Doença Aguda , Células da Medula Óssea , Bandeamento Cromossômico , Rearranjo Gênico , Histona-Lisina N-Metiltransferase , Humanos , Imunofenotipagem , Hibridização in Situ Fluorescente , Interfase , Cariotipagem , Proteína de Leucina Linfoide-Mieloide , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real
10.
Zhonghua Nei Ke Za Zhi ; 55(4): 293-7, 2016 Apr 01.
Artigo em Chinês | MEDLINE | ID: mdl-27030618

RESUMO

OBJECTIVE: To analyze the efficacy of sorafenib on the treatment of patients diagnosed as acute myeloid leukemia(AML) with FLT3-ITD mutation. METHODS: From January 2012 to February 2015, 42 cases of AML with FLT3-ITD mutation according to MICM (morphology, immunology, cytogenetics and molecular) diagnosis system in our hospital were retrospectively analyzed. Thirty-two cases were refractory to chemotherapy or relapsed, who were treated with sorafenib or combined with chemotherapy. Ten patients relapsed after allogeneic hematopoietic stem cell transplantation (allo-HSCT), who were retreated with sorafenib or combined with donor lymphocyte infusion (DLI) or chemotherapy. In the first group, 13 of 32 patients accepted allo-HSCT. RESULTS: The overall response rate of all 42 patients was 73.8%, including 4 (9.5%) complete molecular remission (CMR), 9 (21.4%) complete remission (CR), 8 (19%) complete remission with incomplete hematologic recovery (CRi), 10 (23.8%) partial remission (PR), and 11 (26.2%) none remission (NR). The response rate of sorafenib alone for 17 patients was 70.6%, and that of sorafenib plus chemotherapy was 66.7% (P=0.555). Thirteen patients who received allo-HSCT included 6 CMR/CR/CRi, 4 PR, and 3 NR before transplant. The 2-year overall survival (OS) rate and progress free survival (PFS) rate in all patients were 36.9% and 28.7%, and the corresponding median time were 18 months and 9 months respectively. The 2-year OS rate in 23 patients who received sorafenib combined with allo-HSCT was superior to that in 19 patients not receiving allo-HSCT (45.5% vs 23.9%, P=0.041), so was PFS rate (44.0% vs 9.7%, P=0.014). Twelve cases died of disease progression, four of infection, and one of chronic graft versus host disease after transplant. CONCLUSIONS: Sorafenib combined with chemotherapy improves response rate of AML patients with FLT3-ITD mutation. Those who are treated with sorafenib plus allo-HSCT obtain better long-term survival.


Assuntos
Antineoplásicos/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda/terapia , Niacinamida/análogos & derivados , Compostos de Fenilureia/uso terapêutico , Tirosina Quinase 3 Semelhante a fms/genética , Intervalo Livre de Doença , Doença Enxerto-Hospedeiro , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Mutação , Niacinamida/uso terapêutico , Indução de Remissão , Estudos Retrospectivos , Sorafenibe , Taxa de Sobrevida , Resultado do Tratamento
11.
Zhonghua Xue Ye Xue Za Zhi ; 37(12): 1054-1059, 2016 Dec 14.
Artigo em Chinês | MEDLINE | ID: mdl-28088969

RESUMO

Objective: To explore the clinical features of lymphoplasmacytic diseases with MyD88 L265P mutation. Methods: To analyze the distribution of MYD88 L265P mutation in patients with lymphoplasmacytic diseases by using of ARMS PCR-CE. Results: There were 25(30.9%) MyD88 L265P mutated patients in 81 patients. The mutation was frequently observed in 14 patients with WM (77.8%, 14/18), 2 patients with lymphoplasmacytic lymphoma (66.7%, 2/3), 1 acute lymphocytic leukemia patient (50.0%, 1/2), 3 multiple myeloma patients (30.0%, 3/10), 1 patient with monoclonal gammopathy of undetermined significance (25%, 1/4), 3 patients with chronic lymphocytic leukemia (13.0%, 3/23) and 1 lymphoma patient (4.8%, 1/21). 20 (80%, 20/25) patients were identified with IgM subtype. Compared with wild-type group of 56 cases, mutated patients were older (median age: 67 years vs 55 years, P< 0.001), with lower WBC count (median count: 5.23 × 109/L vs 10.80 × 109/L, P=0.001), lower HGB level (median count: 85 g/L vs 119 g/L, P<0.001). Conclusion: MyD88 L265P mutation was mainly observed in patients with IgM subtype lymphoplasmacytic diseases, and Waldenstrom' s macroglobulinemia was the most common disease. Compared with the wild-type group, patients with MyD88 L265P mutation were older and had lower WBC count, lower level of HGB. However, further studies were needed to test the prognostic value of MyD88 L265P mutation.


Assuntos
Mieloma Múltiplo/genética , Mutação , Fator 88 de Diferenciação Mieloide/genética , Macroglobulinemia de Waldenstrom/genética , Genótipo , Humanos , Imunoglobulina M , Leucemia Linfocítica Crônica de Células B , Linfoma , Reação em Cadeia da Polimerase , Prognóstico
12.
Zhonghua Xue Ye Xue Za Zhi ; 37(12): 1070-1076, 2016 Dec 14.
Artigo em Chinês | MEDLINE | ID: mdl-28088972

RESUMO

Objective: To observe the effects of matrix metalloproteinases (MMP)-2 and MMP-9 secreted by leukemic cells on tight junction proteins ZO-1, claudin-5 and occluding and the permeability of the blood-brain barrier (BBB) and explore the mechanisms of MMP-2 and MMP-9 in leukemic cell infiltration of the central nervous system (CNS). Methods: The mRNA expressions of MMP-2 and MMP-9 in leukemic cell lines SHI-1, HL-60 and U937 were detected by quantitative RT-PCR. The MMP inhibitor GM6001 was used to inhibit the secretion of MMP-2 and MMP-9. RNA interference (RNAi) was used to knock down the expression of MMP-2 and MMP-9. Zymography was used to analyze the secretion of MMP-2 and MMP-9 in the supernatant of different leukemia cell lines treated or untreated with drugs, as well as the RNAi-treated cells. An in vitro BBB model composed of human brain microvascular endothelial cells (BMVECs) was developed on a Matrigel-based insert. Cell invasion through a barrier of Matrigel-based human basement membrane and the BMVECs-based human BBB barrier was assayed to measure the invasive capacity and the capacity to breakdown the BBB of different leukemia cell lines treated or untreated with drugs, as well as the RNAi-treated cells. The morphologic changes of BMVECs after co-culture with different leukemia cell lines treated or untreated with drugs, as well as the RNAi-treated cells in vitro BBB models were observed by invert microscopy and tight junction proteins in these BMVECs were analyzed with a laser-scanning confocal microscope. Results: ①The mRNA expression in different leukemic cell lines shown a pronounced transcription of MMP-2 and - 9, and the transcriptional level in SHI-1 cells was the highest among all leukemic cell lines tested (P<0.01). The data of activities of MMP-2 and -9 were consistent with the results of mRNA expression and SHI-1 displayed higher capacity of invasion (P<0.01). ②After incubation 24h with different leukemic cells, the BMVECs disrupted to loss cell-cell contacts and grew in single cell. Confocal imaging showed down-regulations of ZO-1, claudin-5 and occluding accompanied by the disruption of BBB in vitro models. SHI-1 cells had stronger alterations to BMVECs, tight junction proteins and the permeability of the BBB than HL-60 and U937 cells. However, GM6001 and the knock-down of MMP-2 and MMP-9 altered the responses of BBB. They reduced the degradation of three tight junction proteins with a decreased permeability of BBB. Conclusion: MMP-2 and MMP-9 secreted by leukemic cells could disrupt the BBB by degrading the tight junction proteins ZO-1, claudin-5 and occluding, which contributed the infiltration of leukemic cell into CNS.


Assuntos
Barreira Hematoencefálica , Neoplasias do Sistema Nervoso Central/enzimologia , Leucemia/enzimologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Animais , Técnicas de Cocultura , Células Endoteliais , Humanos , Interferência de RNA , Células U937
13.
Acta Biomater ; 9(4): 6123-33, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23271041

RESUMO

Polyelectrolyte multilayer capsules, promising candidates for multifunctional drug delivery systems, have recently received increased interest. However, the low encapsulation efficiency of drugs and the lack of reports about animal experiments have greatly slowed down their development for drug delivery. Here, a polyelectrolyte multilayer capsule filled with bovine serum albumin gel (BSA-gel-capsule) was constructed by a layer-by-layer assembly technique and thermally induced gelation of BSA. Owing to the charge variability of BSA with change in pH, BSA-gel-capsules not only showed a pronounced accumulation effect of drugs into capsules, but also displayed excellent pH-controlled loading and release properties. Moreover, a remarkable targeting action to the lung was discovered after intravenous injection of fluorescein isothiocyanate (FITC)-labeled BSA-gel-capsules into mice. After treatment with doxorubicin-loaded BSA-gel-capsules, effective cytotoxicity against B16-F10 cells and inhibition of the pulmonary melanoma growth were revealed. This paper introduces a new type of smart microstructure with notable pH-responsive ability. This material renders feasible the intravenous administration of polyelectrolyte microcapsules, which will be a big step towards their application as drug delivery vehicles.


Assuntos
Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Doxorrubicina/administração & dosagem , Nanocápsulas/química , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Soroalbumina Bovina/química , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Difusão , Doxorrubicina/química , Eletrólitos/química , Géis/química , Concentração de Íons de Hidrogênio , Camundongos , Camundongos Endogâmicos ICR , Nanocápsulas/administração & dosagem
14.
J Int Med Res ; 37(1): 37-46, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19215672

RESUMO

The Janus kinase 2 (JAK2) V617F mutation has considerably helped understanding of the molecular pathogenesis of chronic myeloproliferative disorders (MPD), hence this study investigated for the first time the mutational status and relative quantitation of JAK2 V617F mRNA in Chinese patients with chronic MPD. The study cohort comprised 123 chronic MPD patients (35 with polycythaemia vera [PV], 85 with essential thrombocythaemia [ET], three with idiopathic myelofibrosis [IMF]). Blood samples examined by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) and capillary electrophoresis showed that the prevalence of the JAK2 V617F mutation was 100%, 62.4% and 66.7% in PV, ET and IMF patients, respectively. The proportion of JAK2 V617F mutated mRNA was 89.5% in homozygotes and 57.9% in heterozygotes; 18 PV heterozygous patients showed significantly higher mutated JAK2 mRNA levels than 36 heterozygous ET patients. Six of 93 patients exhibited abnormal karyotypes, but specific chromosomal abnormality was not found. The combination of ARMS-PCR and capillary electrophoresis enables quantitative assay of JAK2 V617F mutation, which helps in chronic MPD diagnosis and estimation of minimal residual disease.


Assuntos
Povo Asiático/genética , Janus Quinase 2/análise , Janus Quinase 2/genética , Transtornos Mieloproliferativos/enzimologia , Transtornos Mieloproliferativos/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Doença Crônica , Citogenética , Humanos , Janus Quinase 2/metabolismo , Pessoa de Meia-Idade , Mutação/genética , Transtornos Mieloproliferativos/sangue
15.
J Int Med Res ; 36(6): 1273-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19094436

RESUMO

The aim of this study was to evaluate the efficacy of recombinant adenovirus p53 agent (rAd-p53) injection combined with cisplatin (CDDP) for the treatment of malignant pleural or peritoneal effusion. After puncture drainage, patients in the treatment group (n = 27) received intracavitary administration of rAd-p53 (2 x 10(12) virus particles) once a week for 4 weeks. At 48 h after each rAd-p53 injection, patients were given intracavitary administration of cisplatin 60 mg/m(2). This administration procedure continued once a week for 4 weeks. The control group (n = 21) received the same intracavitary therapy as the treatment group but without rAd-p53 therapy. Efficacy was evaluated by clinical observations, computed tomography, tumour markers, Karnofsky score and short-term follow-up. The total effective rates for the treatment group (63.0%) were significantly higher than for the control group (42.9%), suggesting that the treatment group benefited over the control group. In conclusion, rAd-p53 therapy is a safe and effective treatment for advanced malignant pleural or peritoneal effusion.


Assuntos
Antineoplásicos/uso terapêutico , Ascite/terapia , Cisplatino/uso terapêutico , Terapia Genética , Derrame Pleural Maligno/terapia , Proteínas Recombinantes/uso terapêutico , Proteína Supressora de Tumor p53/uso terapêutico , Adenovírus Humanos/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Ascite/sangue , Ascite/patologia , Líquido Ascítico/efeitos dos fármacos , Líquido Ascítico/patologia , Biomarcadores Tumorais/sangue , Terapia Combinada , Feminino , Genes p53 , Humanos , Masculino , Pessoa de Meia-Idade , Derrame Pleural Maligno/sangue , Derrame Pleural Maligno/patologia , Resultado do Tratamento , Proteína Supressora de Tumor p53/genética
16.
Biochemistry ; 39(14): 3972-8, 2000 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-10747785

RESUMO

Extensive structure-activity studies done with Taxol have identified the side chain at C-13 as one of the requirements for biological activity. Baccatin III, an analogue of Taxol lacking the C-13 side chain, has none of the biological characteristics of Taxol. Since 2-m-azido Taxol, a Taxol derivative with a m-azido substituent in the C-2 benzoyl ring, has greater activity than Taxol, we questioned whether 2-m-azido baccatin III might be active. 2-m-Azido baccatin III inhibited the proliferation of human cancer cells at nanomolar concentrations, blocked cells at mitosis, and reorganized the interphase microtubules into distinct bundles, a typical morphological change induced by Taxol. In contrast to 2-m-azido baccatin III, 2-p-azido baccatin III was similar to baccatin III, having no Taxol-like activity, further indicating the specificity and significance of the 2-meta position substituent. Molecular modeling studies done with the C-2 benzoyl ring of Taxol indicated that it fits into a pocket formed by His227 and Asp224 on beta-tubulin and that the 2-m-azido, in contrast to the 2-p-azido substituent, is capable of enhancing the interaction between the benzoyl group and the side chain of Asp224. The observation that the C-13 side chain is not an absolute requirement for biological activity in a taxane molecule has enabled the development of a new common pharmacophore model between Taxol and the epothilones.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/química , Paclitaxel/química , Paclitaxel/farmacologia , Taxoides , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Humanos , Modelos Moleculares , Paclitaxel/análogos & derivados , Conformação Proteica , Relação Estrutura-Atividade
17.
Skeletal Radiol ; 29(1): 49-53, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10663590

RESUMO

The Magnetic Resonance Imaging (MRI) appearances of primary osseous hemangiopericytoma (HPC) have been rarely described. We report on a 46-year-old Chinese man with primary osseous HPC of the right tibia. The characteristic vascular distribution of this tumor, presenting with a "spoke-wheel" appearance on MR images and with angiographic correlation, is described. Although not pathognomonic, this MR appearance may be an important finding in suggesting the diagnosis of osseous HPC.


Assuntos
Angiografia , Neoplasias Ósseas/diagnóstico , Hemangiopericitoma/diagnóstico , Imageamento por Ressonância Magnética , Tíbia , Amputação Cirúrgica , Neoplasias Ósseas/cirurgia , Diagnóstico Diferencial , Hemangiopericitoma/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Tíbia/diagnóstico por imagem , Tíbia/patologia , Tíbia/cirurgia
18.
Cancer Chemother Pharmacol ; 44(2): 131-7, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10412947

RESUMO

PURPOSE: Eleutherobin, a natural product, is an antimitotic agent that promotes the polymerization of stable microtubules. Although its mechanism of action is similar to that of Taxol, its structure is distinct. A structure-activity profile of synthetic eleutherobin derivatives that have modifications at C3, C8 and C15 was undertaken to define the structural requirements for microtubule stabilization and cross-resistance in Taxol-resistant cell lines. METHODS: The biological activity of five eleutherobin analogs was assessed using three techniques: (1) cytotoxicity and drug-resistance in three paired Taxol-sensitive and -resistant cell lines; (2) polymerization of microtubule protein in vitro in the absence of GTP and (3) induction of microtubule bundle formation in NIH3T3 cells. RESULTS: Eleutherobin had an IC50 value comparable to that of Taxol, whereas neoeleutherobin, which has a carbohydrate domain that is enantiomeric with that of the parent compound, was less cytotoxic and had 69% of the maximum microtubule polymerization ability of eleutherobin. Both of these compounds exhibited cross-resistance in MDRI-expressing cell lines. Removal or replacement of the C15 sugar moiety resulted in reduced microtubule polymerization and cytotoxicity compared to eleutherobin and loss of cross-resistance in the cell lines SKVLB and J7-T3-1.6, both of which express high levels of P-glycoprotein. By contrast, removal of the urocanic acid group at C8 resulted in virtually complete abrogation of biological activity. The compound lost its ability to polymerize microtubules, and its cytotoxicity was reduced by a minimum of 2000-fold in lung carcinoma A549 cells. CONCLUSIONS: Removal or modification of the sugar moiety alters the cytotoxic potency of eleutherobin and its pattern of cross-resistance in Taxol-resistant cells, although such compounds retain a small percentage of the microtubule-stabilizing activity of eleutherobin. The N(1)-methylurocanic acid moiety of eleutherobin, or perhaps some other substituent at the C8 position, is essential for Taxol-like activity. These findings will be important for the future design and the synthesis of new and more potent eleutherobin derivatives.


Assuntos
Alcaloides/farmacologia , Antineoplásicos/farmacologia , Diterpenos , Paclitaxel/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/análise , Cálcio/farmacologia , Resistencia a Medicamentos Antineoplásicos , Humanos , Microtúbulos/efeitos dos fármacos , Relação Estrutura-Atividade , Tubulina (Proteína)/metabolismo , Células Tumorais Cultivadas
19.
J Biol Chem ; 272(13): 8129-32, 1997 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-9079624

RESUMO

Metablastin (also called p19, stathmin, prosolin, p18, Lap18, and oncoprotein 18) is a highly conserved, cytosolic 149-amino acid polypeptide that is expressed in immature vertebrate cells and undergoes extracellular factor- and cell cycle-regulated serine phosphorylation. The protein was shown recently to destabilize microtubules in vitro (Belmont, L., and Mitchison, T. J. (1996) Cell 84, 623-631). Here we demonstrate that microinjection of recombinant metablastin induces a loss of microtubules in COS-7 cells. This effect is enhanced by serine-to-alanine mutations at several phosphorylation sites and virtually abolished by aspartate substitution at a single site, Ser-63. We also show that stoichiometric amounts of metablastin prevent assembly and promote disassembly of microtubules in vitro. Interestingly, the phosphorylation site mutations of metablastin that have dramatic differential effects in intact cells do not alter the ability of metablastin to block tubulin assembly in vitro. The data suggest that phosphorylation of metablastin controls its microtubule-destabilizing activity in vivo but that this regulation may require additional cellular factors. This control mechanism is poised to play a critical role in the dynamic reorganization of the cellular microtubule network that occurs during morphogenesis and mitosis.


Assuntos
Proteínas dos Microtúbulos , Microtúbulos/metabolismo , Fosfoproteínas/metabolismo , Animais , Antineoplásicos/farmacologia , Células COS , Interfase , Microinjeções , Mutagênese Sítio-Dirigida , Nocodazol/farmacologia , Fosforilação , Proteínas Recombinantes/metabolismo , Serina/metabolismo , Estatmina
20.
Clin Cancer Res ; 2(12): 1981-92, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9816157

RESUMO

The purpose of this study was to quantitate the expression of human MDR1 mRNA levels in normal endometrium and in endometrial carcinoma and to determine the association of MDR1 levels with prognostic indicators. Endometrial samples from 43 postmenopausal patients with endometrial carcinoma and 38 patients (controls) with benign disease undergoing hysterectomy were snap-frozen. MDR1 levels were determined by quantitative reverse transcription-PCR (RT-PCR) and compared to sensitive and resistant cell lines. Immunohistochemistry was done with MM4.17, an anti-MDR1 antibody, on paraffin sections, and the results were compared to those obtained from RT-PCR. Data was analyzed using the Kruskal-Wallis and Bonferroni tests, setting the P value at 0.05. In both postmenopausal endometrial tissue and tumors, MDR1 expression was localized to the epithelial cell layer. Comparison of immunohistochemistry and RT-PCR results demonstrated a correlation of 80%. In control patients, MDR1 expression was significantly higher in postmenopausal endometrium (n = 15) than in the proliferative premenopausal endometrium (n = 15; P = 0.0024). MDR1 expression in all tumors was lower than that measured in the postmenopausal controls. Between each tumor group, there was no significant difference in the MDR1 levels observed. MDR1 expression was significantly lower in patients with high nuclear grade (n = 18) tumors when compared to patients with low nuclear grade (n = 14; P = 0.04) tumors. Comparison of MDR1 levels with multiple prognostic indicators for endometrial cancer was only significant for nuclear grade. The data indicate that MDR1 expression is not a major component of the drug resistance observed in primary endometrial tumors.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/análise , Neoplasias do Endométrio/metabolismo , Endométrio/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Idoso , Neoplasias do Endométrio/química , Neoplasias do Endométrio/patologia , Endométrio/química , Endométrio/citologia , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Prognóstico , RNA Mensageiro/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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