Cases reported "Multiple Myeloma"

Filter by keywords:



Filtering documents. Please wait...

1/6. cytokines prevent dexamethasone-induced apoptosis via the activation of mitogen-activated protein kinase and phosphatidylinositol 3-kinase pathways in a new multiple myeloma cell line.

    A new human myeloma cell line, OPM-6, was established from the peripheral blood of a patient with advanced IgG-kappa plasma cell leukemia. Cytogenetic and phenotypic analysis confirmed that the cells were derived from the patient's leukemic cells. insulin-like growth factor-1 (IGF-1) acts as an autocrine growth factor in these cells. In addition, OPM-6 cells were particularly sensitive to dexamethasone (DEX), when endogenous IGF-1 was blocked. Under these conditions, >95% of the DEX-treated cells died within 36 h. Therefore, OPM-6 represents a potentially powerful tool for the analysis of the molecular mechanisms of DEX-induced apoptosis, because it is possible to easily analyze the direct effects of DEX using this system. Using this culture system of OPM-6, we demonstrated that the treatment with DEX plus a monoclonal antibody to the human IGF-1 receptor (alphaIGF-1R) leads to the down-regulation of the gene expression of Bcl-xL, an antiapoptotic gene, and the activation of CPP32 during this apoptotic process. IFN-alpha as well as IL-6 prevented DEX plus alphaIGF-1R-induced apoptosis, and this prevention was blocked by the mitogen-activated protein kinase kinase inhibitor, PD098059, or the phosphatidylinositol 3-kinase inhibitor, wortmannin. Therefore, both IL-6 and IFN-alpha blocked DEX plus alphaIGF-1R-induced apoptosis through activation of the mitogen-activated protein kinase and phosphatidylinositol 3-kinase pathways.
- - - - - - - - - -
ranking = 1
keywords = apoptosis
(Clic here for more details about this article)

2/6. Hyperthermia-induced cell death by apoptosis in myeloma cells.

    We have analyzed by morphological (TEM) and histochemical (TUNEL reaction) criteria the type of cell death occurring in one case of human multiple myeloma after hyperthermia. Samples of cells examined immediately at the end of two treatments with a 15-day interval showed a significant degeneration, mostly demonstrating features of apoptosis (cell shrinkage, dna fragmentation, karyorrhexis). The possible causes of the lag period between heating and apoptosis onset-expression are discussed.
- - - - - - - - - -
ranking = 0.85714285714286
keywords = apoptosis
(Clic here for more details about this article)

3/6. tamoxifen-based treatment induces clinically meaningful responses in multiple myeloma patients with relapsing disease after autotransplantation.

    tamoxifen has been shown to induce apoptosis in multiple myeloma cell lines and primary myeloma cells. Daily tamoxifen was given to 12 consecutive multiple myeloma patients who either relapsed following autologous stem cell transplantation (11) or had progressive disease on conventional chemotherapy (1). methotrexate was also given biweekly to enhance the antiangiogenetic effect. Two patients achieved complete remission lasting 8 and 18 months. Two additional patients had stable disease (SD) for 7 and 11 months. All responders were men and the earliest signs of response were seen after approximately 6-8 weeks of treatment. The regimen was very well tolerated. Speculations about a possible mechanism of action of tamoxifen in multiple myeloma are discussed.
- - - - - - - - - -
ranking = 0.14285714285714
keywords = apoptosis
(Clic here for more details about this article)

4/6. The proteasome inhibitor PS-341 potentiates sensitivity of multiple myeloma cells to conventional chemotherapeutic agents: therapeutic applications.

    The proteasome inhibitor PS-341 inhibits nuclear factor-kappaB (NF-kappaB) activation, induces apoptosis in cancer cells, including multiple myeloma (MM) cells, and has marked clinical activity as a monotherapy for MM. In this study, we found that subtoxic concentrations of PS-341 potently sensitized MM cell lines and patient cells to DNA-damaging chemotherapeutic agents such as doxorubicin and melphalan, including cells resistant to these drugs and those isolated from a patient who had relapsed after PS-341 monotherapy. Moreover, PS-341 abolished cell adhesion-mediated drug resistance. Using gene expression profiling and proteomic analysis, we demonstrate that PS-341, among its other proapoptotic effects, down-regulates the expression of several effectors involved in the cellular response to genotoxic stress. These data suggest that, in addition to down-regulating the expression of apoptosis inhibitors, PS-341 inhibits genotoxic stress response pathways and thereby restores sensitivity to DNA-damaging chemotherapeutic agents. These studies, therefore, provide the framework for clinical use of this agent in combination with conventional chemotherapy.
- - - - - - - - - -
ranking = 0.28571428571429
keywords = apoptosis
(Clic here for more details about this article)

5/6. Requirement of soluble factors produced by bone marrow stromal cells on the growth of novel established human myeloma cell line.

    The growth of myeloma cells is believed to be mediated by functional interactions between tumor cells and the marrow environment involving the action of several cytokines. We report on the establishment and characterization of a new human myeloma cell line (TAB1) that can be long-term maintained in the presence of conditioned medium of bone marrow stromal cells (BMCM) and a BMCM independent variant, C2-2. Both cell lines have plasma cell morphology and express plasma cell antigens (CD38, PCA-1 and immunoglobulin kappa light chain). In the absence of BMCM, TAB1 cells undergoing apoptosis were observed. Among the adherent molecules tested, these cells expressed VLA-4, ICAM-1 and H-CAM, but not VLA-5, suggesting that these were mostly immature plasmacytes. Introduction with exogenous IL-6 and/or GM-CSF, which were detected in BMCM, partially supported the proliferation of TAB1 cells. Treatment with anti-IL-6 antibody partially inhibited the proliferation of TAB1 cells cultured with BMCM. These findings strongly suggest that TAB1 required at least two or more factors on their growth in vitro; IL-6 was one of the factors necessary for cell growth. Further studies are required to clarify the precise molecules which support TAB1 cell growth in combination with IL-6, however, TAB1 and its variant C2-2 cells may offer an attractive model to unravel novel molecular mechanisms involved in bone marrow stroma-dependent growth of myeloma cells.
- - - - - - - - - -
ranking = 0.14285714285714
keywords = apoptosis
(Clic here for more details about this article)

6/6. Analysis of histone deacetylase inhibitor, depsipeptide (FR901228), effect on multiple myeloma.

    multiple myeloma (MM) is a neoplastic proliferation of plasma cells and remains an incurable disease because of the development of drug resistance. Histone deacytylase (HDAC) inhibitors are a new class of chemotherapeutic reagents that cause growth arrest and apoptosis of neoplastic cells. Depsipeptide, a new member of the HDAC inhibitors, was found to be safe in humans and has been shown to induce apoptosis in various cancers. In order to evaluate the effects of depsipeptide, a MM cell line, U266 [interleukin (IL)-6 dependent], was analysed for viability and apoptosis. The combined effect of depsipeptide with melphalan and changes in BCL-2 family proteins (BCL-2, BCL-XL, BAX and MCL-1) were also investigated. In addition, the RPMI 8226 cell line (IL-6 independent), and primary patient myeloma cells were also analysed for apoptosis after depsipeptide treatment. Depsipeptide induced apoptosis in both U266 and RPMI 8226 cell lines in a time- and dose-dependent fashion, and in primary patient myeloma cells. We also demonstrated that depsipeptide had an additive effect with melphalan (10 micromol/l). BCL-2, BCL-XL and MCL-1 showed decreased expression in depsipeptide-treated samples. Based on recent clinical trials demonstrating minimal clinical toxicity, our study supports the future clinical utilization of depsipeptide in the management of MM.
- - - - - - - - - -
ranking = 0.71428571428571
keywords = apoptosis
(Clic here for more details about this article)


Leave a message about 'Multiple Myeloma'


We do not evaluate or guarantee the accuracy of any content in this site. Click here for the full disclaimer.