Jerry L. Spivak

Decreased erythropoietin response in patients with the anemia of cancer

Patients with solid tumors are often anemic even before they undergo cytotoxic therapy. Since the cause of the anemia of cancer is unknown, we examined the possible role of erythropoietin. Using a sensitive radioimmunoassay, we determined serum immunoreactive erythropoietin levels in 81 anemic patients with solid tumors. For any given degree of anemia, the serum concentration of immunoreactive erythropoietin was lower in this group of patients than in a group of control patients with iron-deficiency anemia (P = 0.0001). Furthermore, the expected inverse linear relation between serum levels of immunoreactive erythropoietin and of hemoglobin was absent in the group with cancer. The erythropoietin response was further decreased in patients receiving chemotherapy; it was not influenced by the presence or absence of cisplatin in the treatment regimen. The inability of the patients with cancer to produce erythropoietin was not absolute; if they had hypoxemia, adequate erythropoietin production was restored. We conclude that erythropoietin levels are inappropriately low in anemia associated with cancer, and that erythropoietin deficiency may contribute to the development of this form of anemia. Treatment of the anemia of cancer with erythropoietin may be of value.

Human-induced pluripotent stem cells from blood cells of healthy donors and patients with acquired blood disorders

Human induced pluripotent stem (iPS) cells derived from somatic cells hold promise to develop novel patient-specific cell therapies and research models for inherited and acquired diseases. We and others previously reprogrammed human adherent cells, such as postnatal fibroblasts to iPS cells, which resemble adherent embryonic stem cells. Here we report derivation of iPS cells from postnatal human blood cells and the potential of these pluripotent cells for disease modeling. Multiple human iPS cell lines were generated from previously frozen cord blood or adult CD34(+) cells of healthy donors, and could be redirected to hematopoietic differentiation. Multiple iPS cell lines were also generated from peripheral blood CD34(+) cells of 2 patients with myeloproliferative disorders (MPDs) who acquired the JAK2-V617F somatic mutation in their blood cells. The MPD-derived iPS cells containing the mutation appeared normal in phenotypes, karyotype, and pluripotency. After directed hematopoietic differentiation, the MPD-iPS cell-derived hematopoietic progenitor (CD34(+)CD45(+)) cells showed the increased erythropoiesis and gene expression of specific genes, recapitulating features of the primary CD34(+) cells of the corresponding patient from whom the iPS cells were derived. These iPS cells provide a renewable cell source and a prospective hematopoiesis model for investigating MPD pathogenesis.

Impaired Expression of the Thrombopoietin Receptor by Platelets from Patients with Polycythemia Vera

BACKGROUND The cause of polycythemia vera, which originates from a multipotent hematopoietic progenitor cell, is unknown. Thrombopoietin is a hematopoietic growth factor that regulates the production of multipotent hematopoietic progenitor cells and platelets. To evaluate the possibility that an abnormality in thrombopoietin-mediated signal transduction might be involved in the pathogenesis of polycythemia vera, we examined thrombopoietin-induced tyrosine phosphorylation of proteins and the expression of the thrombopoietin receptor in platelets from patients with the disease. METHODS Platelets were isolated from the blood of patients with polycythemia vera or other chronic myeloproliferative disorders and control subjects. The platelets were exposed to either thrombopoietin or thrombin and then lysed for analysis of tyrosine phosphorylation of platelet proteins and the expression of the proteins by means of immunoblotting. Expression of the thrombopoietin receptor (Mpl) by platelets and megakaryocytes was also assessed. RESULTS Thrombopoietin-mediated tyrosine phosphorylation of proteins was impaired in platelets from 20 patients with polycythemia vera and 3 with idiopathic myelofibrosis, but not in 4 patients with essential thrombocytosis, 3 with chronic myelogenous leukemia, 6 with secondary erythrocytosis, 2 with iron-deficiency anemia, 4 with hemochromatosis, or 5 normal subjects. Thrombin-mediated tyrosine phosphorylation of proteins was intact in platelets from patients with polycythemia vera, and the tyrosine kinases and substrates involved in the process were present in normal amounts. However, expression of the platelet thrombopoietin receptor MpI was markedly reduced or absent in 34 of 34 patients with polycythemia vera and in 13 of 14 patients with idiopathic myelofibrosis. Impaired thrombopoietin-induced tyrosine phosphorylation of proteins in patients with these two diseases was uniformly associated with markedly reduced expression of MpI or the lack of its expression. In patients with polycythemia vera, reduced expression of MpI by platelets was associated with reduced expression of MpI by megakaryocytes. CONCLUSIONS Reduced expression of the thrombopoietin receptor MpI is characteristic of polycythemia vera and idiopathic myelofibrosis. The abnormality appears to distinguish polycythemia vera from other-forms of erythrocytosis.

American Society of Clinical Oncology/American Society of Hematology Clinical Practice Guideline Update on the Use of Epoetin and Darbepoetin in Adult Patients With Cancer

PURPOSE To update American Society of Clinical Oncology/American Society of Hematology recommendations for use of erythropoiesis-stimulating agents (ESAs) in patients with cancer. METHODS An Update Committee reviewed data published between January 2007 and January 2010. MEDLINE and the Cochrane Library were searched. RESULTS The literature search yielded one new individual patient data analysis and four literature-based meta-analyses, two systematic reviews, and 13 publications reporting new results from randomized controlled trials not included in prior or new reviews. RECOMMENDATIONS For patients undergoing myelosuppressive chemotherapy who have a hemoglobin (Hb) level less than 10 g/dL, the Update Committee recommends that clinicians discuss potential harms (eg, thromboembolism, shorter survival) and benefits (eg, decreased transfusions) of ESAs and compare these with potential harms (eg, serious infections, immune-mediated adverse reactions) and benefits (eg, rapid Hb improvement) of RBC transfusions. Individual preferences for assumed risk should contribute to shared decisions on managing chemotherapy-induced anemia. The Committee cautions against ESA use under other circumstances. If used, ESAs should be administered at the lowest dose possible and should increase Hb to the lowest concentration possible to avoid transfusions. Available evidence does not identify Hb levels ≥ 10 g/dL either as thresholds for initiating treatment or as targets for ESA therapy. Starting doses and dose modifications after response or nonresponse should follow US Food and Drug Administration-approved labeling. ESAs should be discontinued after 6 to 8 weeks in nonresponders. ESAs should be avoided in patients with cancer not receiving concurrent chemotherapy, except for those with lower risk myelodysplastic syndromes. Caution should be exercised when using ESAs with chemotherapeutic agents in diseases associated with increased risk of thromboembolic complications. Table 1 lists detailed recommendations.

Hematologic abnormalities in the acquired immune deficiency syndrome

Blood and marrow specimens were evaluated from 12 patients with the acquired immune deficiency syndrome (AIDS). Ten patients were anemic, eight leukopenic, and three thrombocytopenic. Pancytopenia was present in two patients and subsequently developed in two others. Reticulocyte counts were not increased in the anemic patients. The most common peripheral blood abnormalities were a left shift in the granulocyte series, lymphopenia, atypical lymphocytes, and vacuolated monocytes. Marrow cellularity was increased in five patients and reduced in three. Marrow reticulin was increased in 10 patients; in three of these, marrow could not be obtained by aspiration. Plasma cells were increased in number in every marrow aspirate, and there was a left shift in the myeloid series in most. Aggregates of atypical lymphocytes or a diffuse increase in marrow lymphocytes occurred in seven patients. An increase in histiocytes was observed in seven marrow aspirates; in five of these, the histiocytes were phagocytizing red cells, white cells, and platelets. Necrosis was present in four marrow specimens. These hematologic abnormalities reflect, in part, the presence of systemic infection, inflammation, and the inanition associated with them. However, the high incidence of myelofibrosis, alterations in marrow cellularity, pancytopenia, and hematophagic histiocytosis indicates that the bone marrow is a target organ in AIDS.

Immunoablative High-Dose Cyclophosphamide without Stem-Cell Rescue for Refractory, Severe Autoimmune Disease

High-dose cytotoxic therapy followed by autologous stem-cell transplantation has been proposed as a novel treatment for severe autoimmune disease [1, 2]. This approach was prompted by autoimmune animal models that demonstrated marked improvement or complete eradication of autoimmune disease after syngeneic marrow transplantation [3, 4]. In addition, allogeneic marrow transplantation (performed chiefly for aplastic anemia) has been reported to eradicate concurrent autoimmune disease [5, 6]. Allogeneic marrow transplantation is not routinely used to treat autoimmune disease because of substantial associated morbidity and mortality. Although interest in the use of high-dose cytotoxic therapy followed by autologous stem-cell transplantation to treat autoimmune disease is increasing, disease progresses or relapses early in many patients [7, 8]. It is unclear whether reappearance of the disease after autologous transplantation results from failure of high-dose therapy to eradicate autoaggressive lymphocytes, reinfusion of autoaggressive lymphocytes with the autograft, or renewed challenge from the autoantigen [7, 8]. However, the success of syngeneic transplantation in animal models and allogeneic transplantation in patients with autoimmune diseases suggests that high-dose cytotoxic therapy may be sufficient to eradicate autoaggressive lymphocytes [8]. We previously found that the immunoablative doses of cyclophosphamide used for transplantation can induce durable, complete remission (median follow-up > 10 years) without stem-cell rescue in most patients with severe aplastic anemia [9]. Because most cases of aplastic anemia result from immune suppression of hematopoiesis [10], high-dose cyclophosphamide without the addition of other cytotoxic immunosuppressive agents seems to ablate the autoaggressive lymphocytes. We also reported that high-dose cyclophosphamide spared hematopoietic stem cells because full hematopoietic recovery occurred [9]. Hematopoietic stem cells express high levels of aldehyde dehydrogenase, an enzyme responsible for cellular resistance to cyclophosphamide, and are therefore resistant to the cytotoxic effects of cyclophosphamide [11, 12]. We investigated the efficacy of high-dose cyclophosphamide without stem-cell rescue in patients with various severe autoimmune diseases. Methods Treatment Schedule Our study was approved by the institutional review boards of Johns Hopkins University and Hahnemann University. After giving informed consent, eight patients (Table 1 and Table 3) with refractory autoimmune disorders received cyclophosphamide (50 mg/kg of body weight per day) intravenously for 4 consecutive days. Granulocyte colony-stimulating factor therapy (5 g/kg per day) was started 6 days after the last dose of cyclophosphamide and was continued until the absolute neutrophil count reached 109 cells/L. Inclusion in the study required failure of two previous therapies. Patients were excluded if their cardiac ejection fraction was less than 0.45, their serum creatinine level was greater than 176.8 mol/L, or they were older than 70 years of age. Red blood cell transfusions were administered to patients with a hematocrit less than 0.25, and platelet transfusions were given to patients with platelet counts less than 20 109 cells/L or clinically significant bleeding. Complete remission required the absence of any clinical or serologic evidence of disease. Complete remission from lupus nephritis was defined as fewer than 10 dysmorphic erythrocytes per high-powered field, absence of cellular casts, and excretion of less than 1 g of protein per day without doubling of the serum creatinine level [13]. For patients with systemic lupus erythematosus, daily activity indices [14] were measured at 3-month intervals. Table 1. Patient Characteristics and Response to High-Dose Cyclophosphamide Table 3. Table 1. Continued Selected Case Reports Patient 1 was a 64-year-old man with a 35-year history of rheumatoid arthritis treated with prednisone and gold. The Felty syndrome had been diagnosed 3 years earlier when the patient developed a perirectal abscess and profound neutropenia (neutrophil count < 0.2 109 cells/L). Examination of bone marrow showed hypercellularity with myeloid maturation arrest. The patient was treated with myeloid growth factors and steroids but showed no response. He required frequent hospitalizations for recurrent infections. Before the patient received high-dose cyclophosphamide, he was positive for antineutrophil antibodies, the neutrophil count was 0.1 109 cells/L, the rheumatoid factor level was elevated, complement levels were depressed, and the Karnofsky score [15] was 40%. The patient tolerated high-dose cyclophosphamide well and had few side effects other than alopecia; he achieved a neutrophil count greater than 0.5 109 cells/L by day 15, and infections (perirectal abscess, pneumonia, and sinusitis) that were present at the time of treatment resolved. Two units of red blood cells and five platelet transfusions were required. The patient is in complete remission 21 months after treatment and has normal peripheral blood counts, has normal complement levels, and is negative for antineutrophil antibodies. He has not been receiving any immunosuppressive agents for more than 15 months. Patient 6 was a 23-year-old woman in whom lupus was diagnosed at 12 years of age after she presented with the Raynaud phenomenon and stomatitis. She later developed severe proteinuria, hyperlipidemia, polyarthralgia, and an extensive skin rash. Renal biopsy performed 4 years before initiation of high-dose cyclophosphamide therapy showed membranous nephropathy. The patient required hospitalization for lupus flares three to four times per year despite treatment with methylprednisolone (4 mg/d), hydroxychloroquine (400 mg/d), azathioprine (150 mg/d), and pulse-dose cyclophosphamide. Before high-dose cyclophosphamide therapy began, the hematocrit was 0.27, the leukocyte count was 2.8 109 cells/L, the platelet count was 278 109 cells/L, and the erythrocyte sedimentation rate was 104 mm/h. Anti-DNA antibodies were present at a titer of 1:320, the C3 level was 0.41 g/L, and the 24-hour urine protein level was 2 g. The patient tolerated high-dose cyclophosphamide well; side effects were alopecia and febrile neutropenia. A neutrophil count greater than 0.5 109 cells/L was reached on day 18, and only six units of red blood cells and three platelet transfusions were needed. The patient is in continuous complete remission 12 months after treatment; the erythrocyte sedimentation rate is 20 mm/h, no anti-DNA antibodies are present, the C3 level is 1.49 g/L, and the 24-hour urine protein level is 86 mg. Immunosuppressive therapy has been tapered to 1 mg of prednisone daily. Results High-dose cyclophosphamide was well tolerated and was associated with rapid hematologic recovery in all eight patients despite their poor medical condition at time of treatment. Four patients were hospitalized for complications of their autoimmune disease, and four patients were being treated for active infections at the time of cyclophosphamide therapy; the median Karnofsky score was 40% (range, 20% to 70%). The median time to achievement of a neutrophil count greater than 0.5 109 cells/L was 17 days (range, 11 to 22 days), and the median time to the last platelet transfusion was 16 days (range, 12 to 33 days). All patients experienced complete alopecia, and six patients required antibiotics for febrile neutropenia. No patient developed hemorrhagic cystitis or mucositis. Patients 2 and 4 eventually died of complications of autoimmune disease. Patient 2, who was treated for autoimmune hemolytic anemia, died of complications of immune thrombocytopenic purpura, which was not present when she was treated with high-dose cyclophosphamide. Autoimmune hemolytic anemia remained in complete remission until the patients death, 16 months after cyclophosphamide therapy. Patient 4 achieved brief remission of immune thrombocytopenic purpura and died of her disease 8 months later. Six patients remain alive, and five (patients 1, 3, 6, 7, and 8) have no symptomatic manifestations of their disease. In addition, four patients have no laboratory or clinical evidence of disease (Table 2). Patient 3, who has the Evans syndrome, shows continued improvement in blood counts; prednisone therapy is being tapered to 10 mg every other day. Patient 3 has been independent of transfusion for more than 10 months and has a normal hemoglobin level and a platelet count of 66 109 cells/L. One of the patients with lupus achieved complete remission; the other still has clinical and serologic evidence of the disease but continues to improve 14 months after treatment. Patient 7, who has the Felty syndrome, is in complete remission 3 months after cyclophosphamide therapy. Patient 10, who has chronic inflammatory demyelinating polyneuropathy, had progressive upper- and lower-extremity paralysis and was unable to walk. Plasmapheresis, intravenous immunoglobulin, and pulse-dose cyclophosphamide therapy had proven ineffective. Three months after therapy with high-dose cyclophosphamide, he has no neurologic manifestations, is not receiving immunosuppressive therapy, and can walk normally. Table 2. Laboratory Results* Discussion Most immunoablative therapy for severe autoimmune disease uses autologous stem-cell rescue after high-dose therapy with cyclophosphamide in combination with other immunosuppressive agents [8]. Although our study was small and the follow-up was relatively short, the results indicate that high-dose cyclophosphamide alone can be effective therapy for some patients with severe autoimmune disease. In addition, our study confirms that high-dose cyclophosphamide (50 mg/kg per day for 4 days) spares hematopoietic stem cells; the kinetics of bone marrow recovery after high-dose cyclophosphamide therapy without stem-cell rescue are similar to those of engraftment after autol

Polo-like Kinase Is a Cell Cycle-regulated Kinase Activated during Mitosis

Previously, we demonstrated that expression of polo-like kinase (PLK) is required for cellular DNA synthesis and that overexpression of PLK is sufficient to induce DNA synthesis. We now report that the endogenous levels of PLK, its phosphorylation status, and protein kinase activity are tightly regulated during cell cycle progression. PLK protein is low in G1, accumulates during S and G2M, and is rapidly reduced after mitosis. During mitosis, PLK is phosphorylated on serine, and its serine threonine kinase function is activated at a time close to that of p34. The phosphorylated form of PLK migrates with reduced mobility on SDS-polyacrylamide gel electrophoresis, and dephosphorylation by purified protein phosphatase 2A converts it to the more rapidly migrating form and reduces the total amount of PLK kinase activity. Purified p34-cyclin B complex can phosphorylate PLK protein in vitro but causes little increase in PLK kinase activity.

American Society of Hematology/American Society of Clinical Oncology clinical practice guideline update on the use of epoetin and darbepoetin in adult patients with cancer

PURPOSE To update American Society of Hematology/American Society of Clinical Oncology recommendations for use of erythropoiesis-stimulating agents (ESAs) in patients with cancer. METHODS An Update Committee reviewed data published between January 2007 and January 2010. MEDLINE and the Cochrane Library were searched. RESULTS The literature search yielded one new individual patient data analysis and four literature-based meta-analyses, two systematic reviews, and 13 publications reporting new results from randomized controlled trials not included in prior or new reviews. RECOMMENDATIONS For patients undergoing myelosuppressive chemotherapy who have a hemoglobin (Hb) level less than 10 g/dL, the Update Committee recommends that clinicians discuss potential harms (eg, thromboembolism, shorter survival) and benefits (eg, decreased transfusions) of ESAs and compare these with potential harms (eg, serious infections, immune-mediated adverse reactions) and benefits (eg, rapid Hb improvement) of RBC transfusions. Individual preferences for assumed risk should contribute to shared decisions on managing chemotherapy-induced anemia. The Committee cautions against ESA use under other circumstances. If used, ESAs should be administered at the lowest dose possible and should increase Hb to the lowest concentration possible to avoid transfusions. Available evidence does not identify Hb levels ≥ 10 g/dL either as thresholds for initiating treatment or as targets for ESA therapy. Starting doses and dose modifications after response or nonresponse should follow US Food and Drug Administration-approved labeling. ESAs should be discontinued after 6 to 8 weeks in nonresponders. ESAs should be avoided in patients with cancer not receiving concurrent chemotherapy, except for those with lower risk myelodysplastic syndromes. Caution should be exercised when using ESAs with chemotherapeutic agents in diseases associated with increased risk of thromboembolic complications. Table 1 lists detailed recommendations.

The revised World Health Organization diagnostic criteria for polycythemia vera, essential thrombocytosis, and primary myelofibrosis: an alternative proposal

In its August 15, 2007, issue, Blood published a proposal for revision of the World Health Organization (WHO) diagnostic criteria for the chronic myeloproliferative disorders (MPDs) polycythemia vera (PV), essential thrombocytosis (ET), and primary myelofibrosis (PMF).[1][1] Algorithms based on

The blood in systemic disorders

* The high rate of proliferation required of the bone marrow renders it highly susceptible to the influence of external factors. * Anaemia is the most common haematological abnormality seen in systemic disorders. * In the anaemia of chronic disease, erythropoietin production is reduced and proliferation of erythroid progenitor cells is also impaired; this anaemia can generally be alleviated by correction of the underlying disease process. * The status of the endocrine system must always be considered in evaluation of a normocytic, normochromic anaemia. * Anaemia in infection can be due to host or parasite factors or to the treatment administered. * Anaemia due to malignant disease responds to erythropoietin therapy in many cases; failure to respond is a poor prognostic sign.