Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026764 (multiple myeloma)
 36,148 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Anemia is a prominent feature of multiple myeloma (MM) and is commonly associated with clinical progression of MM. In addition to being affected by a number of pathogenetic events, including imbalance of the cytokine network, inappropriate erythropoietin (EPO) levels, blood loss, and hemolysis, the erythroid matrix is chronically deteriorated by the malignant plasma cell clone that activates a cytotoxic mechanism directed at the erythroid progenitors. In particular, malignant plasma cells express very high levels of apoptogenic receptors, including both Fas ligand and tumor necrosis factor-related apoptosis-inducing ligand, which trigger apoptosis of immature erythroblasts by stimulating specific death receptors, namely Fas and the complex DR4/DR5. Erythroid cells also weakly express the transcription factor GATA-1, which drives erythroblast maturation by inhibiting apoptosis through antiapoptotic molecules such as EPO and Bcl-xL. This newly discovered pathogenetic mechanism of anemia in MM is based on persistent erythroblast cytotoxicity within the bone marrow that leads to progressive destruction of the erythroid matrix.
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PMID:Recent advances in understanding the pathogenesis of anemia in multiple myeloma. 1295 5

We evaluated the ability of recombinant human erythropoietin (rHuEpo) therapy, given before high-dose therapy (HDT), to allow autologous peripheral blood stem cell transplantation (PBSCT) without red blood cell (RBC) transfusions. Eleven multiple myeloma patients underwent tandem HDT and autologous PBSC, receiving 500 U/kg/week rHuEpo from d 30 after initial transplant. Haemoglobin levels were 9.5 +/- 1.1 g/dl and 12.5 +/- 0.9 g/dl at the first and second transplant respectively (P < 0.001). RBC transfusions were required for 10/11 patients for the first transplant versus 1/11 for the second (P < 0.001). To conclude, a short course of rHuEpo therapy before HDT facilitates the performance of an autologous transplant without RBC transfusions.
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PMID:Tandem high-dose therapy (HDT) for multiple myeloma: recombinant human erythropoietin therapy given between first and second HDT allows second peripheral blood stem cell transplantation without red blood cell transfusion. 1451 Sep 49

Multiple myeloma (MM) is commonly associated with anemia. Several causes have been implicated, but anemia of chronic disease with inadequate erythropoietin (EPO) production related to the inflammatory cytokines appears to be of utmost importance. Interleukin-1 and tumor necrosis factor are capable of suppressing erythropoiesis. Anemia has broad implications. First, the low hemoglobin and hematocrit are associated with poor quality of life and performance and affect daily activity. Second, anemia has an impact on the cardiovascular system. Considering that most MM patients are elderly, this may be even more important. Anemia has been shown to induce or aggravate hypoxia and ischemic complications. Third, anemia has been shown to be a poor prognostic factor in MM. Traditionally, patients with symptomatic anemia were treated with red blood cell transfusions as needed. The introduction of epoetin alfa and epoetin beta into clinical practice opened new avenues to these patients. The administration of epoetins to patients with MM and anemia have been shown to be very useful. Several studies in more than 1000 patients have demonstrated a high response rate (range, 25%-85%; mean, 60%). This response is characterized by a significant increase of hemoglobin, hematocrit, and the number of red blood cells together with a reduction in the blood transfusion requirements. This is also associated with an improved quality of life. Although there is no complete agreement about the role of pretreatment serum EPO levels, many investigators believe that relatively low levels may help in predicting response, thereby limiting the number of potential candidates to receive this expensive therapy. The epoetins are safe and well tolerated with minimal toxicity; however, some concern has been recently raised regarding several dozen patients who developed pure red cell aplasia while on epoetin therapy. However, this adverse effect appears to be extremely rare. Recent data suggest that EPO has additional biologic effects, such as longer-than-expected survival in patients with MM. This observation is further supported by animal studies, demonstrating an antimyeloma effect of EPO in mice models. This effect has been shown to be immune mediated. If these exciting data are confirmed in future clinical trials, this may have significant implications on the treatment of MM.
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PMID:The implications of anemia in multiple myeloma. 1455 75

Recombinant human erythropoietin (rHuEpo) was introduced into clinical practice more than a decade ago, and has been found to be effective in the treatment of several types of anemia, including anemia of end-stage renal failure and cancer-related anemia. No study has suggested that Epo might have an effect on the biology of the disease, nor any survival advantage to cancer patients treated with Epo for anemia has been reported. Here we report six patients with advanced multiple myeloma (MM) with very poor prognostic features, whose expected survival was <6 months. All six patients were treated with rHuEpo for their anemia, either without any chemotherapy or very mild chemotherapy for a short time. Yet, surprisingly they lived for 45-133 months totally from MM diagnosis and 38-94 months with rHuEpo (with a good quality of life). In fact, one patient, is still alive and well, more than 8 yr after chemotherapy was discontinued because of a resistant aggressive disease. The course in these six MM patients led us to hypothesize that Epo might have an antineoplastic or antimyeloma effect. We proceeded and tested that hypothesis in mouse models of myeloma (Mittelman M et al., Proc Natl Acad Sci USA 98:5181,2001). In these models we confirmed that rHuEpo induced tumor regression in about 50% of the BALB/c mice inoculated with MOPC-315 myeloma cells. We then presented evidence that the mechanism is a new immune-mediated phenomenon, via activation of CD8+ T cells. Furthermore, evidence from the literature supports the antineoplastic effect of Epo. Epo might be used as an adjunct immune treatment in various malignant diseases, in addition to the current regimens and chemotherapeutic protocols. Future trials should determine the role of Epo in myeloma and cancer treatment, besides clarifying concerns about the presence of Epo receptors on some tumor cells.
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PMID:Erythropoietin has an anti-myeloma effect - a hypothesis based on a clinical observation supported by animal studies. 1496 33

Anti-rhEPO McAb is valuable for the determination of recombinant human erythropoietin (rhEPO) levels for diagnosis of renal anemia and for doping control analysis. In this paper, anti-rhEPO hybridoma was prepared by fusion of SP2/0 murine myeloma cells with spleen cells isolated from immunized BALB/c mouse, using an enzyme-linked immunosorbent assay (ELISA) method to screen the positive hybridoma. The purified McAb was characterized by ELISA, SDS-PAGE, and Western-blotting. Experimental results showed that the subclass and the light chain of anti-rhEPO McAb was IgG1 and kappa light chain. The molecular weight of anti-rhEPO McAb was 166,000 Daltons. The affinity constant (K(aff)) of anti-rhEPO McAb with coated antigen was 5.0 x 10(5)L/mol.
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PMID:Production and characterization of anti-recombinant human erythropoietin (rhEPO) monoclonal antibody. 1503 20

Erythropoiesis is a complex multistep process encompassing the differentiation of hemopoietic stem cells to mature erythrocytes. The steps involved in this complex differentiation process are numerous and involve first the differentiation to early erythoid progenitors (burst-forming units-erythroid, BFU-E), then to late erythroid progenitors (colony-forming units-erythroid) and finally to morphologically recognizable erythroid precursors. A key event of late stages of erythropoiesis is nuclear condensation, followed by extrusion of the nucleus to produce enucleated reticulocytes and finally mature erythrocytes. During the differentiation process, the cells became progressively sensitive to erythropoietin that controls both the survival and proliferation of erythroid cells. A normal homeostasis of the erythropoietic system requires an appropriate balance between the rate of erythroid cell production and red blood cell destruction. Growing evidences outlined in the present review indicate that apoptotic mechanism play a relevant role in the control of erythropoiesis under physiologic and pathologic conditions. Withdrawal of erythropoietin or stimulation of death receptors such as Fas or TRAIL-Rs leads to activation of a subset of caspase-3, -7 and -8, which then cleave the transcription factors GATA-1 and TAL-1 and trigger apoptosis. In addition, there is evidence that a number of caspases are physiologically activated during erythroid differentiation and are functionally required for erythroid maturation. Several caspase substrates are cleaved in differentiating cells, including the protein acinus whose activation by cleavage is required for chromatin condensation. The studies on normal erythropoiesis have clearly indicated that immature erythroid precursors are sensitive to apoptotic triggering mediated by activation of the intrinsic and extrinsic apoptotic pathways. These apoptotic mechanisms are frequently exacerbated in some pathologic conditions, associated with the development of anemia (ie, thalassemias, multiple myeloma, myelodysplasia, aplastic anemia). The considerable progress in our understanding of the apoptotic mechanisms underlying normal and pathologic erythropoiesis may offer the way to improve the treatment of several pathologic conditions associated with the development of anemia.
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PMID:Apoptotic mechanisms in the control of erythropoiesis. 1520 42

Among 199 patients treated with thalidomide for multiple myeloma, four thromboses occurred in 49 cases during erythropoietin therapy (prevalence 8.1%; annual rate 7.25%), and another 14 events occurred in patients not on erythropoietin (9.3%; 7.56%). Thus, erythropoietin would seem not to increase the risk of thrombosis of myeloma patients receiving thalidomide.
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PMID:Recombinant human erythropoietin and the risk of thrombosis in patients receiving thalidomide for multiple myeloma. 1537 78

Recombinant human erythropoietin administered after peripheral blood stem cell transplantation (PBSCT) has been ineffective for the treatment of anemia. We administered recombinant human erythropoietin alpha (rHuEPO) prior to high-dose therapy after peripheral blood stem cell (PBSC) collection to evaluate its efficacy on transfusion requirements and hematological parameters during the post-transplant aplastic phase. Twenty-two multiple myeloma patients (EPO-MM) were included in the trial to receive rHuEPO 10,000 IU subcutaneous daily starting 30 days before PBSCT. Forty hemoglobin (Hb)-matched patients who had not received rHuEPO before transplant were retrospectively selected (Ctr-MM) for comparative data. None of the patients received transfusions at study entry. All but one patient responded to rHuEPO. However, no significant differences in Hb levels were obtained between the two groups at the time of transplantation. At nadir, the EPO-MM cases had a significantly higher Hb level (median 10 g/dl versus 7.6 g/d; p=0.001). Consequently, less than 20% of EPO-MM patients required packed red blood cell (PRBC) transfusions compared to more than half the Ctr-MM patients (p=0.007). Furthermore, the number of PRBC transfusions performed in the EPO-MM group was significantly lower (median 0 versus 1; p=0.008). Independently of Hb levels at PBSCT, rHuEPO therapy was significantly associated with a lower risk of transfusion requirement. In conclusion, rHuEPO is shown to be effective when administered prior to high-dose therapy in MM.
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PMID:Administration of recombinant human erythropoietin alpha before autologous stem cell transplantation reduces transfusion requirement in multiple myeloma patients. 1548 Aug 19

Multiple myeloma is a neoplasmatic disease of the hematopoietic system which constitutes about 10% of all hematological proliferations. Anemia is a common symptom of myeloma, especially in patients with advanced disease, and its severity correlates with the clinical stage of myeloma. There are several factors involved in the pathogenesis of anemia in multiple myeloma: infiltration of the bone marrow with monoclonal plasma cells, inadequate secretion of erythropoietin, shortened erythrocyte survival time, dysregulated iron metabolism, impaired marrow function due to proinflammatory cytokine secretion, and interaction between erythroblasts and malignant plasma cells. Recent findings indicate an important function of apoptosis in regulating physiological erythropoiesis. In physiological conditions some erythroblasts undergo apoptosis, which is induced by proteins belonging to the TNF family, i.e. Fas(CD95), FasL(CD95L),and TRAIL (TNF-related apoptosis inducing-ligand) with its receptors--DR4 (Death Receptor 4), and DR5 (Death Receptor 5). Expression of Fas, DR4, and DR5 is detected on the cell membrane of erythroblasts in all stages, whereas FasL and TRAIL are present only in more mature erythroblasts. Interaction of mature erythroblast FasL+/TRAIL+ with immature erythroblast FasL-/TRAIL--results in apoptosis of the immature cell, which contributes to the down-regulation of physiological erythropoiesis. The expression of proteins involved in erythropoiesis regulation is controlled by erythropoietin (EPO), which decreases erythroblast susceptibility to FasL and TRAIL stimulation and prevents apoptosis. On the other hand interferon gamma (IFN-gamma) and tumor necrosis factor (TNF) increase Fas expression on erythroid cells and enhance their apoptosis. Malignant plasma cells show increased expression of FasL and TRAIL and decreased expression of Fas, which make them more resistant to apoptotic signals. FasL+/TRAIL+ plasmocytes are involved in anemia pathogenesis in multiple myeloma patients by inducing apoptosis of erythroid cells. Monoclonal plasmocytes also secrete numerous cytokines involved in plasma cell growth, bone marrow neovascularisation and anemia.
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PMID:[Involvement of apoptosis and proinflammatory cytokines in the pathogenesis of anemia in multiple myeloma]. 1553 94

Within the past decade, clinical trials have shown that the presence of anemia can diminish the physical status, functional abilities, and overall quality of life (QOL) of cancer patients and can negatively influence the outcome of their treatment. However, recent preclinical and clinical studies have also shown that increasing hemoglobin levels by administering recombinant human erythropoietin (rHuEPO, epoetin alfa) may ameliorate anemia and, in doing so, improve QOL and possibly result in better treatment outcomes following radiotherapy, chemotherapy, or a combination of these modalities. Several mechanisms by which rHuEPO may improve treatment outcome have been proposed, including correction of tumor hypoxia, increased sensitivity of tumor cells to radiotherapy and chemotherapy, correction of anemia and its associated symptoms (particularly fatigue), and immune-modulated effects of rHuEPO on tumor growth. Improvement of tumor oxygenation by rHuEPO could affect treatment outcome in two ways. First, correction of hypoxia results in the downregulation of hypoxia-inducible factor 1 (HIF-1), a key regulator of cellular adaptive responses to hypoxia (e.g., angiogenesis), including many pathways that are important for tumor growth and metastasis. Interruption of the HIF-1 pathway not only limits growth of the primary tumor but also reduces the potential for the development of more aggressive tumors and metastatic spread, which could ultimately improve treatment outcome. Second, within the tumor, it is the hypoxic cells that are resistant to oxygen-dependent radiotherapy and chemotherapy, and improvement in their oxygenation would increase their sensitivity to the cytotoxic effects of such treatment. Correction of anemia and its associated symptoms, particularly fatigue, can have a beneficial effect on patient QOL, and this in turn may translate into greater tolerance of radiotherapy and chemotherapy, allowing patients to receive full doses and on-schedule dosing, and thus have an increased likelihood of a therapeutic response. Lastly, results of a study using a murine model of multiple myeloma have indicated that rHuEPO may induce an immune-mediated antitumor effect. Therefore, additional research is warranted to further explore the biologic actions of rHuEPO and to determine their relevance to therapeutic outcome.
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PMID:rHuEPO and improved treatment outcomes: potential modes of action. 1559 21


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