Erythropoiesis in multiple myeloma: defective red cell production due to inappropriate erythropoietin production

Comprehensive Next-Generation Sequencing Testing in a Patient with TEMPI Syndrome

TEMPI syndrome is a new and poorly understood disease that is currently considered a type of plasma cell neoplasm with paraneoplastic manifestations. The TEMPI acronym defines the hallmarks of the syndrome: T for telangiectasia; E for erythrocytosis with elevated erythropoietin; M, monoclonal gammopathy; P, perinephric collections; and I, intrapulmonary shunting. Due to the marked erythrocytosis as the most common presenting feature, TEMPI is often misdiagnosed as polycythemia vera. However, unlike polycythemia vera, TEMPI is not associated with a JAK2 mutation. The pathogenesis of TEMPI syndrome is unknown, although a few hypothetical disease mechanisms have been previously discussed. Here we present a new case of TEMPI syndrome, discuss results of a next-generation sequencing (NGS) panel covering 1,425 known cancer-related genes, and review the current literature with focus on an update of the genetics of TEMPI syndrome. This is the first report of TEMPI that includes results of comprehensive NGS testing.

Regulatory Effect and Mechanism of Erythroblastic Island Macrophages on Anemia in Patients with Newly Diagnosed Multiple Myeloma

Objective

To examine the clinical characteristics and anemia-related factors in patients with newly diagnosed multiple myeloma (NDMM), as well as the effect and mechanism of erythroblastic islands (EBIs) and EBI macrophages in NDMM patients with anemia.

Methods

We collected and analyzed clinical data to find anemia-related factors. Using flow cytometry, the numbers and ratios of erythroblasts and EBI macrophages were determined. RNA sequencing (RNA-seq) was used to determine the differences of EBI macrophages in NDMM patients with or without anemia.

Results

Based on the clinical characteristics of NDMM patients with anemia, MCV, abnormal levels of albumin, osteolytic lesions, and Durie-Salmon (DS) stage are risk factors for anemia. Patients with anemia have fewer erythroblasts, erythroblastic islands (EBIs), and EBI macrophages in their bone marrow than patients without anemia. RNA-seq analysis of EBI macrophages from the bone marrow of patients with and without anemia revealed that macrophages from patients with anemia are impaired and tend to promote the production of interleukin-6, which has been demonstrated to be an essential survival factor of myeloma cells and protects them from apoptosis.

Conclusion

In NDMM patients with anemia, EBI macrophages are impaired, which causes anemia in those patients. Our finding highlights the significance of EBI macrophages in anemia in NDMM patients and provides a new strategy for recovery from anemia in these patients.

Erythropoietin in children with hemolytic uremic syndrome: a pilot randomized controlled trial

BACKGROUND

The efficacy of recombinant human erythropoietin (rHuEPO) in sparing red blood cell (RBC) transfusions in children with hemolytic uremic syndrome related to Shiga toxin-producing Escherichia coli (STEC-HUS) is uncertain.

METHODS

We conducted a pilot randomized controlled open trial between December 2018 and January 2021. Children were randomized to the intervention (subcutaneous rHuEPO 50 U/kg three times weekly until discharge + RBC transfusion if hemoglobin ≤ 7 g/dL and/or hemodynamic instability) or to the control arm (RBC transfusion if hemoglobin ≤ 7 g/dL and/or hemodynamic instability). Primary outcome was the number of RBC transfusions received during hospitalization. Secondary outcomes were to explore whether baseline EPO levels were adequate to the degree of anemia, to correlate selected acute phase parameters with the number of RBC transfusions, and to assess possible adverse events.

RESULTS

Twelve patients per arm were included; they were comparable at recruitment and throughout the disease course. Median number of RBC transfusions was similar between groups (1.5, p = 0.76). Most patients had baseline EPO levels adequate to the degree of anemia, which did not correlate with the number of transfusions (r = 0.19, p = 0.44). Conversely, baseline (r = 0.73, p = 0.032) and maximum lactic dehydrogenase levels (r = 0.78, p = 0.003), creatinine peak (r = 0.71, p = 0.03) and dialysis duration (r = 0.7, p = 0.04) correlated significantly with RBC requirements. No side effects were recorded.

CONCLUSION

In children with STEC-HUS, the administration of rHuEPO did not reduce the number of RBC transfusions. Larger studies addressing higher doses and similar severity of kidney failure at rHuEPO initiation (e.g. at start of dialysis) are warranted.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03776851. A higher resolution version of the Graphical abstract is available as Supplementary information.

The Key Role of Hepcidin-25 in Anemia in Multiple Myeloma Patients with Renal Impairment

Background and objectives: Anemia is common in multiple myeloma (MM) and is caused by a complex pathomechanism, including impaired iron homeostasis. Our aim is to evaluate the biomarkers of iron turnover: serum soluble transferrin receptor (sTfR) and hepcidin-25 in patients at various stages of MM in relation with markers of anemia, iron status, inflammation, renal impairment and burden of the disease and as predictors of mortality. Materials and methods: Seventy-three MM patients (six with smoldering and 67 with symptomatic disease) were recruited and observed for up to 27 months. Control group included 21 healthy individuals. Serum sTfR and hepcidin were measured with immunoenzymatic assays. Results: MM patients with and without anemia had higher sTFR compared to controls, while only anemic patients had higher hepcidin-25. Both hepcidin-25 and sTfR were higher in anemic than non-anemic patients. Higher hepcidin-25 (but not sTfR) was associated with increasing MM advancement (from smoldering to International Staging System stage III disease) and with poor response to MM treatment, which was accompanied by lower blood hemoglobin and increased anisocytosis. Neither serum hepcidin-25 nor sTfR were correlated with markers of renal impairment. Hepcidin-25 predicted blood hemoglobin in MM patients independently of other predictors, including markers of renal impairment, inflammation and MM burden. Moreover, both blood hemoglobin and serum hepcidin-25 were independently associated with patients’ 2-year survival. Conclusions: Our results suggest that hepcidin-25 is involved in anemia in MM and its concentrations are not affected by kidney impairment. Moreover, serum hepcidin-25 may be an early predictor of survival in this disease, independent of hemoglobin concentration. It should be further evaluated whether including hepcidin improves the early diagnosis of anemia in MM.

Improving cancer treatments via dynamical biophysical models

Despite significant advances in oncological research, cancer nowadays remains one of the main causes of mortality and morbidity worldwide. New treatment techniques, as a rule, have limited efficacy, target only a narrow range of oncological diseases, and have limited availability to the general public due their high cost. An important goal in oncology is thus the modification of the types of antitumor therapy and their combinations, that are already introduced into clinical practice, with the goal of increasing the overall treatment efficacy. One option to achieve this goal is optimization of the schedules of drugs administration or performing other medical actions. Several factors complicate such tasks: the adverse effects of treatments on healthy cell populations, which must be kept tolerable; the emergence of drug resistance due to the intrinsic plasticity of heterogeneous cancer cell populations; the interplay between different types of therapies administered simultaneously. Mathematical modeling, in which a tumor and its microenvironment are considered as a single complex system, can address this complexity and can indicate potentially effective protocols, that would require experimental verification. In this review, we consider classical methods, current trends and future prospects in the field of mathematical modeling of tumor growth and treatment. In particular, methods of treatment optimization are discussed with several examples of specific problems related to different types of treatment.

Erythroferrone and hepcidin as mediators between erythropoiesis and iron metabolism during allogeneic hematopoietic stem cell transplant

Hematopoietic cell transplantation (HCT) brings important alterations in erythropoiesis and iron metabolism. Hepcidin, which regulates iron metabolism, increases in iron overload or inflammation and decreases with iron deficiency or activated erythropoiesis. Erythroferrone (ERFE) is the erythroid regulator of hepcidin. We investigated erythropoiesis and iron metabolism after allogeneic HCT in 70 patients randomized between erythropoietin (EPO) treatment or no EPO, by serially measuring hepcidin, ERFE, CRP (inflammation), soluble transferrin receptor (sTfR, erythropoiesis), serum iron and transferrin saturation (Tsat; iron for erythropoiesis) and ferritin (iron stores). We identified biological and clinical factors associated with serum hepcidin and ERFE levels. Serum ERFE correlated overall with sTfR and reticulocytes and inversely with hepcidin. Erythroferrone paralleled sTfR levels, dropping during conditioning and recovering with engraftment. Inversely, hepcidin peaked after conditioning and decreased during engraftment. Erythroferrone and hepcidin were not significantly different with or without EPO. Multivariate analyses showed that the major determinant of ERFE was erythropoiesis (sTfR, reticulocytes or serum Epo). Pretransplant hepcidin was associated with previous RBC transfusions and ferritin. After transplantation, the major determinants of hepcidin were iron status (ferritin at all time points and Tsat at day 56) and erythropoiesis (sTfR or reticulocytes or ERFE), while the impact of inflammation was less clear and clinical parameters had no detectable influence. Hepcidin remained significantly higher in patients with high compared to low pretransplant ferritin. After allogeneic HCT with or without EPO therapy, significant alterations of hepcidin occur between pretransplant and day 180, in correlation with iron status and inversely with erythroid ERFE.

Prediction of Early Treatment Response in Multiple Myeloma Using MY-RADS Total Burden Score, ADC, and Fat Fraction From Whole-Body MRI: Impact of Anemia on Predictive Performance

Background: The recently released Myeloma Response Assessment and Diagnosis System (MY-RADS) for multiple myeloma (MM) evaluation by whole-body MRI (WB-MRI) describes the total burden score. However, assessment is confounded by red bone marrow hyperplasia in anemia. Objective: To assess utility of the MY-RADS total burden score, ADC, and fat fraction (FF) from WB-MRI in predicting early treatment response in patients with newly diagnosed MM and to compare these measures' utility between patients with and without anemia. Methods: This retrospective study included 56 patients (mean age 57.4±9.6 years; 40 men, 16 women) with newly diagnosed MM who underwent baseline WB-MRI including DWI and mDixon sequences. Two radiologists recorded total burden score using MY-RADS and measured ADC and FF of diffuse and focal disease sites. Mean values across sites were derived. Interobserver agreement was evaluated; readers' mean assessments were used for further analyses. Presence of deep response after four cycles of induction chemotherapy was recorded. Patients were classified as anemic if having hemoglobin less than 100 g/L. Utility of WB-MRI parameters in predicting deep response was assessed. Results: A total of 24/56 patients showed deep response; a total of 25/56 patients had anemia. Interobserver agreement, expressed using intraclass correlation coefficients, ranged from 0.95 to 0.99. Among patients without anemia, those with deep response compared with those without deep response exhibited lower total burden score (9.0 vs 18.0), lower ADC (0.79x10-3mm²/s vs 1.08x10-3mm²/s), and higher FF (0.21 vs 0.10) (all p<.001). The combination of these three parameters (optimal cutoffs: <15 for total burden score, <0.84×10-3mm²/s for ADC, >0.16 for FF) achieved sensitivity of 93.8%, specificity of 93.3%, and accuracy of 93.5% for predicting deep response. In patients with anemia, none of the three parameters were significantly different between those with and without deep response (all p>.05), and the combination of parameters achieved sensitivity of 56.3%, specificity of 100.0%, and accuracy of 72.0%. Conclusion: Low total burden score, low ADC, and high FF from WB-MRI may predict deep response in MM, though only among those patients without anemia. Clinical Impact: WB-MRI findings may help guide determination of prognosis and initial treatment selection in MM.

Gene Silencing of Transferrin-1 Receptor as a Potential Therapeutic Target for Human Follicular and Anaplastic Thyroid Cancer

Herein, we assess the gene expression changes activated in thyroid tumors through a computational approach, using the MapReduce algorithm. Through this predictive analysis, we identified the TfR1 gene as a critical mediator of thyroid tumor progression. Then, we investigated the effect of TfR1 gene silencing through small interfering RNA (siRNA) in the expression of extracellular signal-regulated kinase 1/2 (Erk1/2) pathway and c-Myc in human differentiated follicular and undifferentiated anaplastic thyroid cancer. The expression levels of cyclin D₁, p53, and p27, proteins involved in cell cycle progression, were also evaluated. The effect of TfR1 gene silencing through siRNA on the apoptotic pathway activation was also tested. Computational prediction and in vitro studies demonstrate that TfR1 plays a key role in thyroid cancer and that its downregulation was able to inhibit the ERK pathway, reducing also c-Myc expression, which blocks the cell cycle and activates the apoptotic pathway. We demonstrate that TfR1 plays a crucial role for a rapid and transient activation of the ERK signaling pathway, which induces a deregulation of genes involved in the aberrant accumulation of intracellular free iron and in drug resistance. We also suggest that TfR1 might represent an important target for thyroid cancer therapy.

A Case of Multiple Myeloma Presenting with Gastrointestinal Bleeding and Evans Syndrome

Autoimmune events are rare in multiple myeloma (MM). Herein, we report a rare case of a patient presenting with recurrent gastrointestinal (GI) bleeding of unknown origin, also having pancytopenia eventually diagnosed as MM with Evans syndrome. This is an uncommon disorder presenting as autoimmune hemolytic anemia (AIHA) with immune thrombocytopenia purpura (ITP). A 56-year-old African American male presenting with recurrent GI bleeds and pancytopenia of unknown origin developed acute colonic diverticulitis on recurrent admissions, and sigmoid colectomy with primary anastomosis was performed. Flow cytometry with serum protein electrophoresis eventually revealed IgG MM with elevated Kappa/Lambda ratio. Bone marrow biopsy revealed 80% to 90% Kappa clonal plasma cells confirming MM. Direct antiglobulin test (DAT) was positive with pancytopenia. The patient initially showed a good response to chemotherapy with thrombocytopenia improving with intravenous (I/V) dexamethasone. DAT done after completion of initial chemotherapy was negative. However, his disease relapsed after three months with pancytopenia and DAT becoming positive again. The patient was restarted on chemotherapy for debulking, which resulted in a negative DAT again after two months, but pancytopenia did not improve. The patient eventually passed away due to subarachnoid hemorrhage. We highlight only this fourth reported case because of its unique presentation. In elderly patients with unknown cause of GI bleeding with pancytopenia, blood dyscrasias, especially MM, should be considered. Autoimmune workup if positive might warrant the use of steroids for pancytopenia, which can improve thrombocytopenia in MM with Evans syndrome but not anemia.

Response to therapeutic monoclonal antibodies for multiple myeloma in African Americans versus whites

BACKGROUND

Myeloma occurs disproportionately in African Americans, with disparities in outcomes potentially caused by access to care, cytogenetics, and immunity. A gap in knowledge of immune function dissimilarities between African Americans and whites exists. Data for other diseases suggest innate differences in immunity and inflammatory markers, with potential implications for therapeutic monoclonal antibodies reliant on secondary immune activation for activity.

METHODS

Patients receiving daratumumab or elotuzumab, lenalidomide, and dexamethasone were retrospectively studied with a primary endpoint of response at 2 (daratumumab) or 4 months (elotuzumab). Secondary endpoints included stable disease or better at the same points, treatment duration, time to best response, and adverse events.

RESULTS

Eighty patients were included; baseline characteristics were balanced with the exception of the stage at diagnosis, which was more advanced in African Americans. No statistically significant difference in response was seen: 37.9% in whites versus 11.8% in African Americans with daratumumab (P = .090) and 60% in whites versus 44% in African Americans with elotuzumab (P = .462). There were no differences in the duration of treatment, the time to best response, or adverse events. Common potential immune-related adverse events in both arms were fatigue (39%), back pain (30%), and infusion reactions (40%). Anemia was significantly associated with a response to daratumumab (P = .02); no patients without anemia responded at 2 months, whereas 34.4% of patients with anemia did.

CONCLUSIONS

No significant difference in response, duration of treatment, or time to response was seen by race, although a trend toward greater early response rates in whites was observed. In these cohorts, as in other analyses, African American patients tended to present with later stage disease.

Effectiveness of darbepoetin alfa in multiple myeloma patients receiving chemotherapy including novel agents

BACKGROUND

The aim of this study was to evaluate the effects of darbepoetin alfa (DA) on hemoglobin (Hb) concentration and the need for transfusions in multiple myeloma (MM) patients receiving chemotherapy with novel agents.

METHODS

Of 251 patients with MM who received DA therapy for at least 4 weeks, 142 who did not receive RBC transfusion during 4 weeks after DA initiation and started DA therapy at baseline Hb <10.0 g/dL were analyzed.

RESULTS

After 4 weeks of DA therapy, 80 (60.6%) of 132 patients with evaluable data had Hb that increased ≥1.0 g/dL from baseline, while 50 (37.9%) had Hb that increased ≥2.0 g/dL from baseline. Pretreatment Hb level did not correlate with the proportion of patients with increased Hb. The median duration of DA therapy was 9.0 weeks. At the end of DA therapy, of 135 patients with evaluable data, 86 (60.6%) had Hb that increased ≥1.0 g/dL from baseline, while 67 (47.2%) had Hb that increased ≥2.0 g/dL from baseline. Stage III disease according to the International Staging System and absence of myeloma bone disease at diagnosis were independent predictors of higher Hb response during early DA therapy.

CONCLUSION

We demonstrated the efficacy of DA therapy in a homogeneous group of MM patients receiving chemotherapy. DA therapy significantly increased Hb concentration, regardless of baseline Hb level.

Multiple myeloma in Niger Delta, Nigeria: complications and the outcome of palliative interventions

Background

Multiple myeloma (MM) is one of the hematological malignancies that require palliative care. This is because of the life-threatening nature and the suffering associated with the illness. The aim of this study is to bring to the fore the complications experienced by people living with MM in the Niger-Delta region of Nigeria and the outcome of various palliative interventions.

Methods

This was a 10-year multi-center retrospective study of 26 patients diagnosed and managed in three major centers in the Niger-Delta region of Nigeria from January 2003 to December 2012. Information on the clinical, laboratory, radiological data, and palliative treatment was obtained at presentation and subsequently at intervals of 3 months until the patient was lost to follow-up.

Result

The mean duration from onset of symptoms to diagnosis was 13.12 months (95% CI, 6.65–19.58). A total of 16 (61.5%), eight (30.8%), and two subjects (7.7%) presented in Durie–Salmon (DS) stages III, II, and I, respectively. The complications presented by patients at diagnoses included bone pain (84.6%), anemia (61.5%), nephropathy (23.1%), and hemiplegia (35%). All the patients received analgesics, while 50.0% received blood transfusion, 56.7% had surgery performed, 19% had hemodialysis, and 3.8% received radiotherapy. A total of 10 (38%) patients benefited from bisphosphonates (BPs). A total of 57.6% of patients were on melphalan–prednisone (MP) double regimen, while 19% and 8% patients were on MP–thalidomide and MP–bortezomib triple regimens, respectively. A total of 3.8% of patients at DS stage IIIB disease had autologous stem-cell transplantation (ASCT). Only 7.6% of the myeloma patients survived up to 5 years post diagnosis. The overall mean survival interval was 39.7 months (95% CI, 32.1–47.2).

Conclusion

Late diagnosis and inadequate palliative care account for major complications encountered by MM patients in the Niger-Delta region of Nigeria. This could be responsible for the poor prognostic outcome and low survival interval of MM individuals in this region. There is, therefore, a need to improve the quality of palliative care received by myeloma patients in this region. This is achievable via provision of relevant and affordable health care facilities for diagnosis and treatment of the disease.

Polycythaemia: an unusual presentation of multiple myeloma

In contrast to anaemia, polycythaemia is a distinctly uncommon finding in patients with multiple myeloma. We describe the presence of otherwise unexplained polycythaemia in a 57-year-old Caucasian man who was found to have IgG κ multiple myeloma. After treatment of myeloma, the polycythaemia resolved. We reviewed previous reports of polycythaemia associated with multiple myeloma and discuss potential pathophysiological mechanisms that link these 2 conditions.

Factors and Predictors of Response with Epoetin Alfa for Chemotherapy-Related Anemia

Objective:

To describe the value of specific factors and predictors that influence the use of epoetin alfa for anemia in adults with cancer receiving chemotherapy with or without radiation therapy.

Data Sources:

Data search restricted to English-language literature on epoetin alfa identified by MEDLINE searches (1990-July 2000) and other pertinent literature was conducted.

Data Synthesis:

Anemia of chronic disease (ACD) is a common finding among cancer patients. Patients receiving repeated or multiple chemotherapy regimens alone or with radiation therapy may worsen ACD. Blood transfusion is the cornerstone of treatment. Risks associated with allogeneic blood transfusion are clearly established. This includes alteration of the immune system, acute allergic reactions, viral and bacterial infections, tumor reappearance, and reduced quality of life (QOL). As the demand for blood increased and periodic supply shortages occurred, healthcare centers began seeking alternatives to blood transfusion. Recombinant human erythropoietin (epoetin alfa) is a prophylactic or treatment option that can reduce the need for blood transfusion with an improved QOL. Albeit clinically beneficial, epoetin alfa is expensive. Using predictors during early use with epoetin alfa, clinicians can identify patients most likely and least likely to benefit from further therapy, thus preventing costly outcomes. The change in hemoglobin (>0.5–1.0 g/dL) combined with either endogenous erythropoietin concentration (<100 mU/mL) or absolute reticulocyte count increase (>40,000 cells/uL) two to four weeks after starting therapy provided the most powerful prediction of response to epoetin alfa.

Conclusions:

Key factors and predictors with epoetin alfa can optimize therapy outcomes in cancer patients receiving chemotherapy.

Bone marrow infiltration by multiple myeloma causes anemia by reversible disruption of erythropoiesis

Multiple myeloma (MM) infiltrates bone marrow and causes anemia by disrupting erythropoiesis, but the effects of marrow infiltration on anemia are difficult to quantify. Marrow biopsies of newly diagnosed MM patients were analyzed before and after four 28-day cycles of non-erythrotoxic remission induction chemotherapy. Complete blood cell counts and serum paraprotein concentrations were measured at diagnosis and before each chemotherapy cycle. At diagnosis, marrow area infiltrated by myeloma correlated negatively with hemoglobin, erythrocytes, and marrow erythroid cells. After successful chemotherapy, patients with less than 30% myeloma infiltration at diagnosis had no change in these parameters, whereas patients with more than 30% myeloma infiltration at diagnosis increased all three parameters. Clinical data were used to develop mathematical models of the effects of myeloma infiltration on the marrow niches of terminal erythropoiesis, the erythroblastic islands (EBIs). A hybrid discrete-continuous model of erythropoiesis based on EBI structure/function was extended to sections of marrow containing multiple EBIs. In the model, myeloma cells can kill erythroid cells by physically destroying EBIs and by producing proapoptotic cytokines. Following chemotherapy, changes in serum paraproteins as measures of myeloma cells and changes in erythrocyte numbers as measures of marrow erythroid cells allowed modeling of myeloma cell death and erythroid cell recovery, respectively. Simulations of marrow infiltration by myeloma and treatment with non-erythrotoxic chemotherapy demonstrate that myeloma-mediated destruction and subsequent reestablishment of EBIs and expansion of erythroid cell populations in EBIs following chemotherapy provide explanations for anemia development and its therapy-mediated recovery in MM patients.

Abnormal erythropoiesis and the pathophysiology of chronic anemia

Erythropoiesis, the bone marrow production of erythrocytes by the proliferation and differentiation of hematopoietic cells, replaces the daily loss of 1% of circulating erythrocytes that are senescent. This daily output increases dramatically with hemolysis or hemorrhage. When erythrocyte production rate of erythrocytes is less than the rate of loss, chronic anemia develops. Normal erythropoiesis and specific abnormalities of erythropoiesis that cause chronic anemia are considered during three periods of differentiation: a) multilineage and pre-erythropoietin-dependent hematopoietic progenitors, b) erythropoietin-dependent progenitor cells, and c) terminally differentiating erythroblasts. These erythropoietic abnormalities are discussed in terms of their pathophysiological effects on the bone marrow cells and the resultant changes that can be detected in the peripheral blood using a clinical laboratory test, the complete blood count.

Management of Cancer Anemia

Anemia complicates the course of disease in about 50% of patients with cancer, and negatively affects their quality of life. A correct approach to therapy should consider all the possible causes and patients need to be treated accordingly. The observation that erythropoietin production is often blunted offers new treatment possibilities. Fifty to 70% of anemic patients respond to rHuEpo, given in a three times or once-a-week schedule. The novel hyperglycosylated protein darbepoetin permits longer intervals between administrations, thanks to its longer half-life, and a once per cycle or once-a-month schedule is a reasonable target. Correction of anemia improves the quality of life, and it has been hypothesized that improvement of cognitive function may derive from a direct effect of Epo on CNS cells. Although anemia is an adverse prognostic factor in cancer, results of recent clinical trials have raised the question whether rHuEpo may favor neoplastic cell proliferation. Results are conflicting at the moment, and further studies are required before arriving at a conclusion. Data available so far do not indicate any negative effect of darbepoetin on the outcome of cancer disease, nor has the production of anti-darbepoetin antibodies or PRCA been reported, a complication observed in less than 200 patients with anemia due to renal insufficiency and treated with rHuEpo alpha.

Iron in multiple myeloma

Multiple myeloma is a non-curable B-cell malignancy in which iron metabolism plays an important role. Patients with this disorder almost universally suffer from clinically significant anemia, which is often symptomatic, and which is due to impaired iron utilization. Recent studies have indicated that the proximal cause of dysregulated iron metabolism and anemia in these patients is cytokine-induced upregulation of hepcidin expression. Malignant myeloma cells are dependent on an increased influx of iron, and therapeutic efforts are being made to target this requirement. The studies detailing the characteristics and biochemical abnormalities in iron metabolism causing anemia and the initial attempts to target iron therapeutically are described in this review.

How to approach chronic anemia

We present herein an approach to diagnosing the cause of chronic anemia based on a patient's history and complete blood cell count (CBC). Four patterns that are encountered frequently in CBCs associated with chronic anemias are considered: (1) anemia with abnormal platelet and/or leukocyte counts, (2) anemia with increased reticulocyte counts, (3) life-long history of chronic anemia, and (4) anemia with inappropriately low reticulocytes. The pathophysiologic bases for some chronic anemias with low reticulocyte production are reviewed in terms of the bone marrow (BM) events that reduce normal rates of erythropoiesis. These events include: apoptosis of erythroid progenitor and precursor cells by intrinsic and extrinsic factors, development of macrocytosis when erythroblast DNA replication is impaired, and development of microcytosis due to heme-regulated eIF2α kinase inhibition of protein synthesis in iron-deficient or thalassemic erythroblasts.

Darbepoetin alpha in the treatment of cancer chemotherapy-induced anemia

Anemia is a common, but underestimated and undertreated, complication of patients with cancer receiving chemo- or radiotherapy, and negatively affects their quality of life (QoL). Erythropoietic proteins (EPS) offer an effective treatment of cancer anemia and ameliorate QoL, although their use requires the correct targeting of hemoglobin increase to avoid thromboembolic complications. Currently the effort is focused on offering patients this effective treatment with reduced frequency of administration. Higher weekly single doses of recombinant human Epo (rHuEpo) either alpha or beta, instead of three times per week, have been proposed for the treatment. The pharmacokinetic and pharmacodynamic characteristics of the hyperglycosylated protein darbepoetin alpha permit even longer inter vals between administrations. Every other week or every three weeks schedules have shown results (erythropoietic response, reduction of transfusion requirements, and improvement of QoL) comparable with those of weekly rHuEpo.

Supportive therapy in multiple myeloma

In this chapter we want to give an overview on various supportive measures, which help to prevent or to fight complications of multiple myeloma, improve patient wellbeing and increase safety of administration of specific anti-myeloma therapy.

Complications of multiple myeloma

Multiple myeloma, also known as myeloma or plasma cell myeloma, is a progressive hematologic disease. Complications of multiple myeloma include renal insufficiency, hematologic complications (anemia, bone marrow failure, bleeding disorders), infections, bone complications (pathologic fractures, spinal cord compression, hyercalcemia), and neurologic complications (spinal cord and nerve root compression, intracranial plasmacytomas, leptomeningeal involvement, among others). This article reviews these various complications connected to multiple myeloma, examining their various causes and possible treatment.

Prediction of the responsiveness to treatment with erythropoiesis-stimulating factors: a prospective clinical study in patients with solid tumors

OBJECTIVE

Treatment with erythropoiesis-stimulating factors (ESFs) can ameliorate anemia associated with cancer and chemotherapy. However, half of anemic cancer patients do not respond even to high doses. To determine factors that are predictive of a treatment response, a multicenter, prospective study was performed.

PATIENTS AND METHODS

Investigated factors were baseline erythropoietin, reticulocytes and soluble transferrin receptor (sTfR) after 2 weeks, and reticulocytes and hemoglobin after 4 weeks. Anemic patients with solid tumors received 150 microg/week of darbepoetin concomitantly with chemotherapy. The dose was doubled if hemoglobin did not increase by >1 g/dl after 4 weeks. Patients were considered responders if hemoglobin increased by >or=2 g/dl or reached a level >or=12 g/dl within 8-12 weeks.

RESULTS

In total, 196 patients were enrolled; 61% of the intention-to-treat (ITT) and 68% of the per-protocol population were responders. In the ITT population, the hemoglobin increase after 4 weeks indicated an 11-fold higher chance of response (odds ratio, 11.0; 95% confidence interval [CI], 5.1-23.6; sensitivity, 88%; specificity, 60%). In a multiple logistic regression model including all factors, the area under the receiver operating characteristic curve was 0.78 (95% CI, 0.71-0.84). The combination of sTfR after 2 weeks and hemoglobin after 4 weeks was as predictive as the combination of all five tested factors.

CONCLUSION

So far, an early hemoglobin increase remains the single most predictive factor for response to ESF treatment. In contrast to anemic patients with lymphoproliferative malignancies, serum erythropoietin had little predictive value in patients with solid tumors.

Evaluation of Hypochromic Erythrocytes in Combination with sT fR-F Index for Predicting Response to r-HuEPO in Anemic Patients with Multiple Myeloma

The purpose of this study was to evaluate the sTfR-F index and hypochromic erythrocytes (HYPO%) as potential predictors of response to recombinant human erythropoietin (r-HuEPO) of anemic patients with multiple myeloma (MM) before treatment, as well as early in the course of treatment. Twenty-six newly diagnosed anemic MM patients received r-HuEPO 30,000 IU/wk sc, for six weeks. The sTfR-F index and HYPO% were determined at baseline and at weeks 2 and 6. Patients were classified in 1 of 4 categories of a diagnostic plot, according to erythropoietic state (ES I-IV), defined by the combination of sTfR-F index and HYPO%. Sixteen of 20 patients in ES I and II before treatment responded to r-HuEPO, whereas none of the 6 patients in ES III and IV responded (P < .001). At week 2, 44% of patients who responded and 60% of the nonresponders were in functional iron deficiency (FID) and the proportion increased to 69% and 80%, respectively, by week 6. Seven of the patients who did not respond received in addition 200 mg iron sucrose IV weekly, for the next 4 weeks, and 6 of them responded. These results suggest that combination of sTfR-F index and HYPO% in a diagnostic plot can be used as a predictive model to recognize patients who will benefit from r-HuEPO and identify FID requiring iron supplementation, before treatment and early in the course of treatment, contributing thus to optimization of r-HuEPO therapy.

Renal, hematologic and infectious complications in multiple myeloma

Renal failure is a common complication in patients with multiple myeloma. It is generally due to tubular light-chain damage, and it is reversible in about 50% of patients. The reversibility rate depends on the degree of light-chain nephropathy. The initial therapy should consist of dexamethasone- or cyclophosphamide-based regimens. High-dose therapy/autologous transplant may be of benefit in selected patients. Early plasma exchange may be useful in patients who have severe renal failure but do not yet require dialysis. Renal replacement with dialysis is a worthwhile measure in patients with end-stage renal failure. Anemia is the most common hematologic complication. About 70% of anemic patients respond to recombinant human erythropoietin (rHuEPO), resulting not only in an increase in the hemoglobin level but also in an improvement in the quality of life. The hemoglobin level should ideally be maintained at around 12 g/dL. Infection is the main cause of morbidity and mortality in patients with myeloma. The highest risk of infection is within the first 2 months of initiation of therapy as well as in patients with renal failure and in those with relapsed and refractory disease.

The impact of anaemia on outcome in cancer

Anaemia is not an inconsequential side effect of cancer and its treatment should not be ignored. Current practice for anaemia management varies and its role in influencing outcome in cancer patients is under recognized. As a common complication of cancer, anaemia is prevalent in virtually all tumour types to varying degrees. Predictive factors for anaemia include baseline haemoglobin concentration, decrease in haemoglobin concentration within the first month of treatment, tumour type, duration of treatment and prior blood transfusions. Interest in the prognostic significance of anaemia in cancer patients has generated extensive clinical research. Data is now published in a wide range of tumour types confirming that anaemia is a negative prognostic indicator of outcome (e.g. survival, disease-free recurrence and local relapse), with the strongest association in patients receiving radiotherapy. The association has also been documented in patients undergoing chemotherapy and chemoradiation. A retrospective meta-analysis has shown an overall 65% increased risk of death associated with anaemia in cancer patients. The impact of anaemia as an independent prognostic factor for outcome may be mediated by several factors, however the emerging consensus is on the central role of tumour hypoxia. It has been nearly 50 years since R. Thomlinson and L. Gray (British Journal of Cancer 1955, 9: 539) first documented the existence of hypoxia in tumours and it is now well accepted that tumour hypoxia protects tumour cells from therapeutic damage directly by reducing the availability of oxygen-free radicals which are necessary for optimal impact of radiotherapy, certain chemotherapeutic agents and photodynamic therapy. The indirect effects include the impact of hypoxia on gene expression, which affects genetic stability, proliferation kinetics and cellular metabolism. There has been an emergence of preclinical and circumstantial data over recent years that are suggestive of the ability to correct the negative effect of anaemia on outcome by the use of repeated blood transfusions or recombinant human erythropoietin. This has led to some attempts to measure the impact on survival in cancer patients of treating anaemia, but early attempts have served to underline the complexity of the relationship and have produced unexpected results.

Phase III, randomized, double-blind study of epoetin alfa compared with placebo in anemic patients receiving chemotherapy

PURPOSE

To determine whether weekly epoetin alfa could improve hemoglobin (HgB) levels, reduce RBC transfusions, and improve quality of life (QOL) in patients with advanced cancer and with anemia after receiving myelosuppressive chemotherapy.

PATIENTS AND METHODS

This double-blind, placebo-controlled study randomly assigned patients to placebo or epoetin alfa (Ortho Biotech, Bridgewater, NJ) 40,000 U subcutaneous weekly for 16 weeks. QOL, HgB, and RBC transfusions were measured pretreatment and monthly.

RESULTS

The study accrued 344 patients; 330 were assessable for efficacy and 305 were assessable for QOL. Placebo-treated patients had a mean increase in HgB of 0.9 g/dL (range, -3.8 to +5.3) compared with 2.8 g/dL (range, -2.2 to +7.5) for epoetin-treated patients (P < .0001). During the study, 31.7% of placebo-treated patients achieved a > or = 2 g/dL HgB increase compared with 72.7% of epoetin-treated patients (P < .0001). The incidence of RBC transfusion for placebo and epoetin treatment arms was 39.6% and 25.3% (P = .005), respectively. The placebo group received 256 units of RBCs compared with 127 units in the epoetin group (P < .0001). The incidence of toxicity in the groups was similar. Changes in the average QOL scores from baseline to the end of the study were similar in the two groups (P = not significant). The HgB responders (irrespective of treatment arm) had a mean change in Functional Assessment of Cancer Therapy (FACT) fatigue score from a baseline of +5.1 compared with -2.1 for the nonresponders (P = .006).

CONCLUSION

Epoetin alfa significantly improved HgB and reduced transfusions in this patient population. These results support the use of weekly epoetin alfa as an ameliorative agent for cancer-related anemia.

Epoetin alfa corrects anemia and improves quality of life in patients with hematologic malignancies receiving non-platinum chemotherapy

Anemia, a commonly occurring morbidity in patients with cancer, often leads to diminished quality of life (QOL). Numerous clinical trials have shown that epoetin alfa treatment improves hematologic and QOL variables in cancer patients. The clinical trial analysis reported here was performed to assess response to epoetin alfa in patients with hematologic malignancies. Cancer patients with anemia undergoing non-platinum-based chemotherapy who were enrolled in a multinational, randomized (2:1), double-blind, placebo-controlled trial were prospectively stratified by tumor type (hematologic, solid). Efficacy endpoints included proportion of patients transfused after day 28; change in hemoglobin (Hb) level from baseline to last assessment; proportion of treatment responders (increase in Hb > or =2 g/dl unrelated to transfusion) and correctors (patients whose Hb levels reached > or =12 g/dl during the study); and QOL. The protocol was amended before unblinding to prospectively collect and assess survival data 12 months after the last patient completed the study, and survival for the full study cohort was estimated using Kaplan-Meier techniques. Efficacy analyses of hematologic and QOL variables, as well as Kaplan-Meier estimates of survival, were performed post hoc for the hematologic tumor stratum. Among patients with hematologic malignancies, the mean increase in Hb levels was greater with epoetin alfa than with placebo treatment (2.2 vs. 0.3 g/dl). Transfusion requirements were lower in patients who received epoetin alfa versus placebo (25.2 vs. 43.1%), and the proportion of responders and correctors was higher with epoetin alfa than with placebo (75.2 vs. 16.7% and 72.6 vs. 14.8%, respectively). Patients who received epoetin alfa had improved QOL while patients who received placebo had decreased QOL. These results are similar to those seen in the full study cohort, where differences between epoetin alfa and placebo were significant (P<0.05) for all five primary cancer- and anemia-specific QOL domains evaluated. Although the study was not powered for survival, Kaplan-Meier estimates showed a trend in overall survival favoring epoetin alfa in both the full study cohort and the hematologic subgroup. Epoetin alfa treatment was well tolerated. Epoetin alfa therapy increased Hb levels, reduced transfusion requirements, and improved QOL in patients with anemia undergoing non-platinum chemotherapy for hematologic malignancies.

The Implications of Anemia in Multiple Myeloma

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.

Impact of epoetin beta on quality of life in patients with malignant disease

This open-label, prospective study was conducted to compare the impact of epoetin beta vs standard care on quality of life (QoL) in anaemic patients with lymphoid or solid tumour malignancies. A total of 262 anaemic patients (haemoglobin [Hb]<or=11 g dl(-1)) were randomised to a 12-week treatment with s.c. epoetin beta (initial dose 150 IU kg(-1) three times weekly) or standard care. Transfusions were recommended for both groups at an Hb threshold of 8.5 g dl(-1). The primary efficacy variables were improvement in QoL as measured using the Short-Form-36 physical component summary (SF-36 PCS) score and the Functional Assessment of Cancer Therapy fatigue and anaemia subscales (FACT-F and FACT-An). A visual analogue scale (VAS) was also used as a global QoL measure. Clinical response was defined as a >or=2 g dl(-1) increase in Hb level without need of transfusion after the initial 4 weeks of treatment. Baseline to final visit changes in SF-36 PCS, FACT-F and VAS scores were significantly greater with epoetin beta than with standard care (P<0.05); changes in FACT-An subscale score tended to be greater with epoetin beta (P=0.076). Epoetin beta significantly increased Hb concentrations relative to standard care (responders: 47% vs 13%; P<0.001). Levels of endogenous erythropoietin <50 mIU ml(-1) were significantly predictive of response (OR 2.496, 95% CI: 1.21-5.13). Epoetin beta therapy significantly improves QoL compared with standard care in anaemic patients with solid tumours and lymphoid malignancies.

Soluble transferrin receptor for the evaluation of erythropoiesis and iron status

Iron transport in the plasma is carried out by transferrin, which donates iron to cells through its interaction with a specific membrane receptor, the transferrin receptor (TfR). A soluble form of the TfR (sTfR) has been identified in animal and human serum. Soluble TfR is a truncated monomer of tissue receptor, lacking its first 100 amino acids, which circulates in the form of a complex of transferrin and its receptor. The erythroblasts rather than reticulocytes are the main source of serum sTfR. Serum sTfR levels average 5.0+/-1.0 mg/l in normal subjects but the various commercial assays give disparate values because of the lack of an international standard. The most important determinant of sTfR levels appears to be marrow erythropoietic activity which can cause variations up to 8 times below and up to 20 times above average normal values. Soluble TfR levels are decreased in situations characterized by diminished erythropoietic activity, and are increased when erythropoiesis is stimulated by hemolysis or ineffective erythropoiesis. Measurements of sTfR are very helpful to investigate the pathophysiology of anemia, quantitatively evaluating the absolute rate of erythropoiesis and the adequacy of marrow proliferative capacity for any given degree of anemia, and to monitor the erythropoietic response to various forms of therapy, in particular allowing to predict response early when changes in hemoglobin are not yet apparent. Iron status also influences sTfR levels, which are considerably elevated in iron deficiency anemia but remain normal in the anemia of inflammation, and thus may be of considerable help in the differential diagnosis of microcytic anemia. This is particularly useful to identify concomitant iron deficiency in a patient with inflammation because ferritin values are then generally normal. Elevated sTfR levels are also the characteristic feature of functional iron deficiency, a situation defined by tissue iron deficiency despite adequate iron stores. The sTfR/ferritin ratio can thus describe iron availability over a wide range of iron stores. With the exception of chronic lymphocytic leukemia (CLL) and high-grade non-Hodgkin's lymphoma and possibly hepatocellular carcinoma, sTfR levels are not increased in patients with malignancies. We conclude that soluble TfR represents a valuable quantitative assay of marrow erythropoietic activity as well as a marker of tissue iron deficiency.

Negative regulation of erythroblast maturation by Fas-L(+)/TRAIL(+) highly malignant plasma cells: a major pathogenetic mechanism of anemia in multiple myeloma

Multiple myeloma (MM) is associated with severe normochromic/normocytic anemia. This study demonstrates that the abnormal up-regulation of apoptogenic receptors, including both Fas ligand (L) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), by highly malignant myeloma cells is involved in the pathogenesis of the ineffective erythropoiesis and chronic exhaustion of the erythroid matrix. By measuring Fas-L and TRAIL in plasma cells and the content of glycophorin A (GpA) in erythroblasts from a cohort of 28 untreated, newly diagnosed patients with MM and 7 with monoclonal gammopathy of undetermined significance (MGUS), selected in relation to their peripheral hemoglobin values, results showed that both receptors occurred at high levels in 15 severely anemic MM patients. Their marrow erythropoietic component was low and included predominantly immature GpA(+dim) erythroblasts, in contrast with the higher relative numbers of mature GpA(+bright) erythroid cells observed in the nonanemic patients and those with MGUS. In cocultures with autologous Fas-L(+)/TRAIL(+) myeloma cells, the expanded GpA(+dim) erythroid population underwent prompt apoptosis after direct exposure to malignant plasma cells, whereas erythroblasts from nonanemic patients were scarcely affected. The evidence that Fas-L(+)/TRAIL(+) malignant plasma cells prime erythroblast apoptosis by direct cytotoxicity was also supported by the increase of FLICE in fresh immature GpA(+dim) erythroid cells, whereas ICE and caspase-10 increased in subsequent maturative forms. In addition, GATA-1, a survival factor for erythroid precursors, was remarkably down-regulated in fresh erythroblasts from the severely anemic patients. These results indicate that progressive destruction of the erythroid matrix in aggressive MM is due to cytotoxic mechanisms based on the up-regulation in myeloma cells of Fas-L, TRAIL, or both. It is conceivable that the altered regulation of these receptors defines a peculiar cytotoxic phenotype that drives the progression of aggressive MM.

Erythropoietin response is inadequate in cancer patients receiving chemotherapy

The level of serum erythropoietin (EPO) is inappropriately decreased in cancer patients and has been advocated as the main cause of their anemia. In cancer patients, chemotherapy results in a cumulative anemia severe enough to require transfusion. We investigated the changes in serum EPO, hemoglobin, ceruloplasmin, and copper levels in cancer patients receiving chemotherapy. There was a weak but significant inverse relationship between hemoglobin and log[EPO] (r = -0.41; P < .001). Observed/expected serum EPO ratios decline with repeated chemotherapy indicating inadequate EPO response for the degree of anemia. There was no difference in the severity of anemia and in the degree of EPO response between platinum- and non-platinum-treated patients. Ceruloplasmin, copper, and ferritin levels did not change during chemotherapy. Our results suggest that the EPO response is inadequate for the degree of anemia and justifies the use of recombinant human EPO in cancer patients receiving chemotherapy.

Serum erythropoietin and its relation with soluble transferrin receptor in patients with different types of anaemia in a locally defined reference population

Serum erythropoietin (Epo) and soluble transferrin receptor (sTR) were measured in a locally defined reference population (n=100): healthy volunteers (n=50); iron- deficiency anaemia (n=41) and haemolytic anaemia (n=9) (beta-thalassaemia, n = 4; autoimmune, n=5). Our data demonstrated an inverse relationship between erythroid activity and Epo levels. The regression line between Ln Epo and haemoglobin (Hb) was highly significant: P < 0.0001, r2=0.8275, Ln Epo=8.5346-0.04275 Hb, confidence limit 95%. The mean observed/predicted (O/P) ratio of Ln (Epo) was 1.01 +/- 0.11. We demonstrated that the serum Epo concentration in this particular population correlated consistently with clinical measures of erythropoietic activity. sTR, a new index of erythropoiesis, varied from 16.1 to 148 nmol/l, mean 62.0 nmol/l in the anaemic patients' group. The relationship between Ln Epo and Ln sTR was highly significant: P < 0.0001. We conclude that locally defined regression analyses are crucial for correct data interpretation and can indicate whether or not Epo production is appropriate or inappropriate. Serial determinations of sTR could help in the assessment of response to therapeutic doses of Epo.

Monitoring of erythropoiesis by the serum transferrin receptor and erythropoietin

Virtually all cells have transferrin receptors (a transmembrane glycoprotein) on their surface but in a normal adult, 80% of them are in the erythroid marrow. Some of them are lost into the circulation where they can be measured by immuno-assays. A direct and highly significant correlation exists between serum transferrin receptor level and erythron transferrin uptake in humans. The measurement of serum transferrin receptor has wide clinical applications for the quantitation of erythropoiesis. It can be used to study erythropoiesis in situations in which ferrokinetics is not acceptable such as pregnancy. It is particularly useful for serial studies, e.i., for monitoring the recovery of erythropoiesis after stem cell transplantation or after treatment with erythropoietin. Combined with the determination of serum erythropoietin, both evaluated in relation to the degree of anemia, they provide a physiological approach to the diagnosis of anemia. Thus, the simultaneous determination of hematocrit, reticulocytes, serum transferrin receptor and serum erythropoietin has high discriminatory value in distinguishing between a defect in erythroid proliferation, maturation or red cell survival. It is also particularly useful for detecting the presence of multiple mechanisms of anemia in the same patient.

Fas-L up-regulation by highly malignant myeloma plasma cells: role in the pathogenesis of anemia and disease progression

Highly malignant myeloma cells up-regulate their Fas-ligand (Fas-L) to escape immune surveillance by Fas(+) cytotoxic cells. Here it is demonstrated that this abnormality is involved in the pathogenesis of the severe anemia associated with progression of multiple myeloma (MM). By measuring Fas and Fas-L in plasma cells and erythroblasts from 19 MM patients and 5 with monoclonal gammopathies of undetermined significance (MGUS), it was found that both Fas-L(+) myeloma cells and Fas(+) erythroid progenitors were significantly increased in patients with stage III MM whose erythroblasts, cultured in the presence of autologous plasma cells or their supernatant, underwent prompt apoptosis as evaluated by propidium iodide staining, the TUNEL assay, and detection of the APO2.7-reactive mitochondrial antigen. Flow cytometry of fresh erythroblasts revealed a considerable expression of the caspases CPP32 and FLICE in both their constitutive proenzymatic forms and in cleaved subunits. By contrast, their intracytoplasmic expression was defective in patients with inactive disease and MGUS controls. The evidence that Fas-L(+) myeloma clones directly prime erythroblast apoptosis in vivo was further supported by the occurrence of fluorescein isothiocyanate-TUNEL(+) erythroblasts juxtaposed to myeloma cells in bone marrow smears. These results strongly suggest that the deregulated apoptosis in myeloma clones plays an active role in the progressive destruction of the erythroid matrix by a cytotoxic mechanism based on up-regulation of Fas-L.

Modulation of transduced erythropoietin expression by iron

OBJECTIVE

Future prospects for gene therapy of chronic anemias involve expression of the erythropoietin transgene, which is regulated by oxygen tension. However, other factors such as cytokines or the iron load of erythropoietin-expressing cells can concomitantly modulate transgene expression, as shown for the expression of the endogenous erythropoietin gene in human cell lines and in animals. We tested the effects of iron overload or depletion on the expression of the mouse erythropoietin transgene (cDNA), driven by the hypoxia-regulated phosphoglycerate kinase 1 promoter.

MATERIALS AND METHODS

Retrovirally transduced mouse cells (C3H fibroblasts or C2C12 myoblasts) were cultured in normoxia (room air, O2: 21%) or hypoxia (O2: 1.5%) in the presence or absence of hemin (an iron donor) or deferiprone (an iron chelator), both of which easily enter the cell.

RESULTS

Hemin inhibited the hypoxia-induced expression of the transgene. In contrast, deferiprone enhanced the hypoxia-induced expression of the erythropoietin transgene and induced its expression in normoxia.

CONCLUSION

These results show that, in addition to oxygen partial pressure, the intracellular iron content is critical in the modulation of hypoxia-regulated erythropoietin transgene expression.

Relation between S-phase fraction of myeloma cells and anemia in patients with multiple myeloma

In an attempt to define the relation among anemia, tumor mass, and proliferative activity of tumor cells in vivo, we measured the proportion and cell cycle distribution of erythropoietic cells and myeloma cells in the bone marrow of patients with multiple myeloma using four-parameter flow cytometry. Forty-three bone marrow samples from 33 patients with stage II or III disease and normal renal function at diagnosis (n = 9), in partial remission (n = 9), and in progression or relapse after chemotherapy (n = 25) were evaluated. Early and late erythropoietic cells were discriminated based on published light scatter properties in combination with CD71 expression. Myeloma cells were detected by exploiting their strong CD38 positivity and light scatter characteristics. Cell cycle distribution of the three cell populations was determined by propidium iodine staining. In the whole group of patients, hemoglobin (Hb) concentration was inversely correlated with beta2-microglob-ulin (p = 0.03), percentage of marrow CD38++ cells (p = 0.008), and percentage of CD38(++) cells in S phase (S-CD38++; p < 0.001). Partial correlation analysis revealed S-CD38++ to be the only independent predictor of Hb concentration (p < 0.001). No correlation was found between Hb concentration and the S-phase fraction of erythropoietic cells. In the subgroup of patients with moderate to severe anemia, defined as Hb concentration <11 g/dL, Hb level correlated negatively only with S-CD38++ (p < 0.001) but not with beta2-microglobulin and percentage of marrow CD38++ cells. In addition, Hb and the S-phase proportion of early erythropoietic cells correlated positively (p = 0.029). The strong inverse correlation between Hb concentration and percentage of myeloma cells in S phase suggests that in multiple myeloma, tumor proliferative activity may have a more important impact on the development of anemia than tumor mass. The S-phase fraction of tumor cells appears to be the most important pathogenic factor, especially in anemic patients. In these patients, the positive relation between Hb concentration and the S-phase fraction of erythropoietic progenitors indicates that development of anemia is associated with inhibition of erythropoiesis.

Anemia in Children With Cancer Is Associated With Decreased Erythropoietic Activity and Not With Inadequate Erythropoietin Production

A defect in erythropoietin (EPO) production has been advocated as being the main cause of anemia presented at time of diagnosis or during treatment by adults with solid tumors. On the basis of this defect, anemic cancer patients, both adults and children, have been treated with recombinant human EPO (rHuEPO). To further elucidate the pathophysiology of anemia in children with cancer, we measured serum soluble transferrin receptor (sTfR), a quantitative marker of erythropoiesis, and serum EPO at time of diagnosis and during chemotherapy in children suffering from solid tumor or leukemia. We determined serum EPO in 111 children (55 leukemia, 56 solid tumors) at time of diagnosis. In the last 44 patients (23 leukemia and 21 solid tumors), sTfR levels were also measured. Serum EPO together with sTfR levels were also determined in 60 children receiving chemotherapy (29 leukemia, 31 solid tumors). These results were compared with those obtained from appropriate control groups. In all patients, we found a highly significant correlation between the logarithm of EPO (log[EPO]) and the hemoglobin (Hb) level. In all subsets of patients, sTfR levels were inappropriately low for the degree of anemia. Neither leukemic nor solid tumor groups showed a significant inverse relationship between log(sTfR) and the Hb level as would be expected in anemic patients with appropriate marrow response. Thus, in children with cancer, anemia is associated with a decreased total bone marrow erythropoietic activity which, in contrast to what has been reported in anemic cancer adults, is not related to defective EPO production.

© 1998 by The American Society of Hematology.

Controlled multicentre study of the influence of subcutaneous recombinant human erythropoietin on anaemia and transfusion dependency in patients with ovarian carcinoma treated with platinum-based chemotherapy

This randomised controlled multicentre trial evaluated the effectiveness of recombinant human erythropoietin (rhEPO) in preventing anaemia and reducing the need for blood or erythrocyte transfusion in 122 ovarian cancer patients receiving platinum-based chemotherapy. The patients were randomly allocated to receive rhEPO 150 U/kg or 300 U/kg subcutaneously, three times a week, or open control. Patients also received up to 6 cycles of carboplatin or cisplatin, alone or in combination with other cytotoxic agents. Intention-to-treat analysis showed that 39.4% of patients in the control group received at least one blood transfusion, compared with 9.2% of patients treated with rhEPO. Patients treated with rhEPO experienced a significantly longer time to first erythrocyte transfusion than the control group and were less likely to experience nadir haemoglobin levels < 10 g/dl (P < 0.001 and < 0.05, respectively). A haemoglobin decrease < 1 g/dl during the first chemotherapy cycle, as well as a low baseline serum erythropoietin concentration, predicted a low transfusion need in rhEPO-treated patients but not in controls. During the study, 103 patients suffered at least one adverse event, but no serious, and only nine non-serious adverse events were considered possibly related to rhEPO therapy. These results indicate that treatment with rhEPO prevents anaemia, it reduces the need for blood or rhEPO erythrocyte transfusion in patients with ovarian cancer receiving platinum-based chemotherapy, and it is well tolerated. A starting dose of 150 U/kg of rhEPO, three times a week, may be recommended.

Anemia in Children With Cancer Is Associated With Decreased Erythropoietic Activity and Not With Inadequate Erythropoietin Production

A defect in erythropoietin (EPO) production has been advocated as being the main cause of anemia presented at time of diagnosis or during treatment by adults with solid tumors. On the basis of this defect, anemic cancer patients, both adults and children, have been treated with recombinant human EPO (rHuEPO). To further elucidate the pathophysiology of anemia in children with cancer, we measured serum soluble transferrin receptor (sTfR), a quantitative marker of erythropoiesis, and serum EPO at time of diagnosis and during chemotherapy in children suffering from solid tumor or leukemia. We determined serum EPO in 111 children (55 leukemia, 56 solid tumors) at time of diagnosis. In the last 44 patients (23 leukemia and 21 solid tumors), sTfR levels were also measured. Serum EPO together with sTfR levels were also determined in 60 children receiving chemotherapy (29 leukemia, 31 solid tumors). These results were compared with those obtained from appropriate control groups. In all patients, we found a highly significant correlation between the logarithm of EPO (log[EPO]) and the hemoglobin (Hb) level. In all subsets of patients, sTfR levels were inappropriately low for the degree of anemia. Neither leukemic nor solid tumor groups showed a significant inverse relationship between log(sTfR) and the Hb level as would be expected in anemic patients with appropriate marrow response. Thus, in children with cancer, anemia is associated with a decreased total bone marrow erythropoietic activity which, in contrast to what has been reported in anemic cancer adults, is not related to defective EPO production.

© 1998 by The American Society of Hematology.

Measurement of the cell proliferation rate of bone marrow erythroid precursors by flow cytometry: initial applications to multiple myeloma

To investigate the pathophysiology of anemia, a two-color flow cytometric method was developed that measures the proliferative rate of the marrow erythroid cells (EPR). The method uses a monoclonal antibody, RC17.2, to identify erythroid precursors and propidium iodide to determine the %S-phase. This technique was then used to test the hypothesis that a decrease in the proliferative rate of the marrow erythroid precursors contributes to the anemia of multiple myeloma. The EPR was determined on the marrow aspirate from 56 patients and the mean EPR was 31.2% (median, 31: range, 14-55). Patients with anemia (n = 36) had a median EPR of 27% compared to 35% for those patients with a normal Hgb (p = < 0.001); however, there was no difference in the % marrow erythroid precursors (p = 0.96) or % marrow plasma cells (p = 0.08) between the two groups. These results suggest that one possible cause for the anemia of myeloma is a decrease in the EPR. This flow cytometric technique may also be useful in studying other anemias.

The role of recombinant erythropoietin for the treatment of anemia in multiple myeloma

The key role of a blunted production of endogenous erythropoietin (EPO) in determining anemia of patients with multiple myeloma (MM) has been definitively established. Thus, several clinical trials have investigated the effects of recombinant EPO (r-EPO) in anemic MM patients. The results of these studies have demonstrated that r-EPO is a safe and effective drug, which results in an increase in Hb levels in the majority of treated patients. However, several factors, such as serum levels of endogenous EPO, severity of anemia, presence of normal erythroid progenitors, serum levels of some cytokines with inhibitory activity on erythroid function and previous treatments, may significantly affect the possibility of response, thereby suggesting the need for careful selection of MM patients for treatment with r-EPO.

Recombinant human erythropoietin in the treatment of chemotherapy-induced anemia and prevention of transfusion requirement associated with solid tumors: a randomized, controlled study

BACKGROUND

Anemia is a common side effect of anticancer chemotherapy. Blood transfusion, previously the only available treatment for chemotherapy-induced anemia, may result in some clinical or subclinical adverse effects in the recipients. Recombinant human erythropoietin (rhEPO) provides a new treatment modality for chemotherapy-induced anemia.

PATIENTS AND METHODS

To evaluate the effect of rhEPO on the need for blood transfusions and on hemoglobin (Hb) concentrations, 227 patients with solid tumors and chemotherapy-induced anemia were enrolled in a randomized, controlled, clinical trial. Of 189 patients evaluable for efficacy, 101 received 5000 IU rhEPO daily s.c., while 88 patients received no treatment during the 12-week controlled phase of the study.

RESULTS

The results demonstrate a statistically significant reduction in the need for blood transfusions (28% vs. 42%, P = 0.028) and in the mean volume of packed red blood cells transfused (152 ml vs. 190 ml, P = 0.044) in patients treated with rhEPO compared to untreated controls. This effect was even more pronounced in patients receiving platinum-based chemotherapy (26% vs. 45%, P = 0.038). During the controlled treatment phase, the median Hb values increased in the rhEPO patients while remaining unchanged in the control group. The response was seen in all tumor types.

CONCLUSIONS

RhEPO administration at a dose of 5000 IU daily s.c. increases hemoglobin levels and reduces transfusion requirements in chemotherapy-induced anemia, especially during platinum-based chemotherapy.

Recombinant human erythropoietin (rhEPO) in the management of anemia and fatigue associated with hematologic malignancies and the myelodysplastic syndromes

Anemia is a common complication in patients with chronic lymphocytic leukemia, non- Hodgkin's lymphoma, multiple myeloma, and the myelodysplastic syndromes (MDS). Al though an inappropriately low serum erythro poietin level often correlates with anemia in these malignancies, this is not always the case. Nevertheless, recombinant human erythropoie tin (rhEPO) has been studied in various hemato logic malignancies and in MDS to correct the anemia and avoid the use of red blood cell transfusions. Clinical benefit has been demon strated in most hematologic malignancies or disorders; however, patients with refractory anemia with ringed sideroblasts, a subset of MDS, are resistant to rhEPO therapy. Interest ingly, the combined use of rhEPO and granulo cyte colony-stimulating factor appears to en hance the response in this subset of patients. Most studies did not include extensive phar macoeconomic or quality of life analyses. Thus, it will be important to define more clearly the lowest effective dose and to identify patients with a high probability of response.