Treatment of cancer-related anemia with epoetin alfa: a review

Targeting erythroid progenitor cells for cancer immunotherapy

Immunotherapy, especially immune checkpoint blockade therapy, represents a major milestone in the history of cancer therapy. However, the current response rate to immunotherapy among cancer patients must be improved; thus, new strategies for sensitizing patients to immunotherapy are urgently needed. Erythroid progenitor cells (EPCs), a population of immature erythroid cells, exert potent immunosuppressive functions. As a newly recognized immunosuppressive population, EPCs have not yet been effectively targeted. In this review, we summarize the immunoregulatory mechanisms of EPCs, especially for CD45+ EPCs. Moreover, in view of the regulatory effects of EPCs on the tumor microenvironment, we propose the concept of EPC-immunity, present existing strategies for targeting EPCs, and discuss the challenges encountered in both basic research and clinical applications. In particular, the impact of existing cancer treatments on EPCs is discussed, laying the foundation for combination therapies. The aim of this review is to provide new avenues for improving the efficacy of cancer immunotherapy by targeting EPCs.

The JAK-STAT pathway: from structural biology to cytokine engineering

The Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway serves as a paradigm for signal transduction from the extracellular environment to the nucleus. It plays a pivotal role in physiological functions, such as hematopoiesis, immune balance, tissue homeostasis, and surveillance against tumors. Dysregulation of this pathway may lead to various disease conditions such as immune deficiencies, autoimmune diseases, hematologic disorders, and cancer. Due to its critical role in maintaining human health and involvement in disease, extensive studies have been conducted on this pathway, ranging from basic research to medical applications. Advances in the structural biology of this pathway have enabled us to gain insights into how the signaling cascade operates at the molecular level, laying the groundwork for therapeutic development targeting this pathway. Various strategies have been developed to restore its normal function, with promising therapeutic potential. Enhanced comprehension of these molecular mechanisms, combined with advances in protein engineering methodologies, has allowed us to engineer cytokines with tailored properties for targeted therapeutic applications, thereby enhancing their efficiency and safety. In this review, we outline the structural basis that governs key nodes in this pathway, offering a comprehensive overview of the signal transduction process. Furthermore, we explore recent advances in cytokine engineering for therapeutic development in this pathway.

A novel NET-related gene signature for predicting DLBCL prognosis

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) is an aggressive malignancy. Neutrophil extracellular traps (NETs) are pathogen-trapping structures in the tumor microenvironment that affect DLBCL progression. However, the predictive function of NET-related genes (NRGs) in DLBCL has received little attention. This study aimed to investigate the interaction between NRGs and the prognosis of DLBCL as well as their possible association with the immunological microenvironment.

METHODS

The gene expression and clinical data of patients with DLBCL were downloaded from the Gene Expression Omnibus database. We identified 148 NRGs through the manual collection of literature. GSE10846 (n = 400, GPL570) was used as the training dataset and divided into training and testing sets in a 7:3 ratio. Univariate Cox regression analysis was used to identify overall survival (OS)-related NETs, and the least absolute shrinkage and selection operator was used to evaluate the predictive efficacy of the NRGs. Kaplan-Meier plots were used to visualize survival functions. Receiver operating characteristic (ROC) curves were used to assess the prognostic predictive ability of NRG-based features. A nomogram containing the clinical information and prognostic scores of the patients was constructed using multivariate logistic regression and Cox proportional risk regression models.

RESULTS

We identified 36 NRGs that significantly affected patient overall survival (OS). Eight NRGs (PARVB, LYZ, PPARGC1A, HIF1A, SPP1, CDH1, S100A9, and CXCL2) were found to have excellent predictive potential for patient survival. For the 1-, 3-, and 5-year survival rates, the obtained areas under the receiver operating characteristic curve values were 0.8, 0.82, and 0.79, respectively. In the training set, patients in the high NRG risk group presented a poorer prognosis (p < 0.0001), which was validated using two external datasets (GSE11318 and GSE34171). The calibration curves of the nomogram showed that it had excellent predictive ability. Moreover, in vitro quantitative real-time PCR (qPCR) results showed that the mRNA expression levels of CXCL2, LYZ, and PARVB were significantly higher in the DLBCL group.

CONCLUSIONS

We developed a genetic risk model based on NRGs to predict the prognosis of patients with DLBCL, which may assist in the selection of treatment drugs for these patients.

Exercise Counteracts the Deleterious Effects of Cancer Cachexia

Simple Summary

This review provides an overview of the effects of exercise training on the major mechanisms related to cancer cachexia (CC). The review also discusses how cancer comorbidities can influence the ability of patients/animals with cancer to perform exercise training and what precautions should be taken when they exercise. The contribution of other factors, such as exercise modality and biological sex, to exercise effectiveness in ameliorating CC are also elaborated in the final sections. We provide meticulous evidence for how advantageous exercise training can be in patients/animals with CC at molecular and cellular levels. Finally, we emphasise what factors should be considered to optimise and personalise an exercise training program in CC.

Abstract

Cancer cachexia (CC) is a multifactorial syndrome characterised by unintentional loss of body weight and muscle mass in patients with cancer. The major hallmarks associated with CC development and progression include imbalanced protein turnover, inflammatory signalling, mitochondrial dysfunction and satellite cell dysregulation. So far, there is no effective treatment to counteract muscle wasting in patients with CC. Exercise training has been proposed as a potential therapeutic approach for CC. This review provides an overview of the effects of exercise training in CC-related mechanisms as well as how factors such as cancer comorbidities, exercise modality and biological sex can influence exercise effectiveness in CC. Evidence in mice and humans suggests exercise training combats all of the hallmarks of CC. Several exercise modalities induce beneficial adaptations in patients/animals with CC, but concurrent resistance and endurance training is considered the optimal type of exercise. In the case of cancer patients presenting comorbidities, exercise training should be performed only under specific guidelines and precautions to avoid adverse effects. Observational comparison of studies in CC using different biological sex shows exercise-induced adaptations are similar between male and female patients/animals with cancer, but further studies are needed to confirm this.

Treatment of anemia in cancer patients undergoing chemotherapy with intravenous ferric carboxymaltose without erythropoiesis-stimulating agents

Background:

Anemia is commonly encountered in cancer patients receiving active chemotherapy. Due to adverse events and presumed negative effects on disease-progression and survival, erythropoiesis-stimulating agents are not frequently used. In this study, we assess the efficacy and safety of intravenous ferric carboxymaltose (FCM) to treat cancer-induced anemia (CIA).

Patients and Methods:

We recruited adult cancer patients on active chemotherapy with a hemoglobin (Hb) level ⩽11.0 g/dL. Based on serum ferritin (sFr) and transferrin saturation (TSAT), patients were divided into 3 groups: group I (absolute iron deficiency, n = 26) with sFr < 30 ng/mL and TSAT < 20%; group II (functional iron deficiency, n = 24) with sFr 30–800 ng/mL and TSAT < 20%; and patients with TSAT ⩾ 20% were placed in group III as “others” (n = 34). All patients were treated with intravenous FCM. Serum hepcidin and C-reactive protein were used as biomarkers to predict response.

Results:

A total of 84 patients with a median age (SD) of 53.8 (10.6) were recruited. Baseline median Hb level was 10.2 (range: 8.3–11.0) gm/dL. At week 12, there was a significant increment in Hb level for patients in groups I and II (median increment: 2.35 and 1.5 gm/dL, respectively), with limited response observed in group III, and most of the increment noted as early as week 3 (⩾1.0 g/dL). Responders tended to have lower levels of hepcidin. No clinically significant adverse events were reported; however, asymptomatic hypophosphatemia was observed in 39 (46.4%) patients.

Conclusions:

Intravenous FCM is a safe and effective treatment option for the management of a subgroup of patients with CIA.

The study was registered at ClinicalTrials.gov [Identifier: NCT04246021]

Study on the Effect of Ginsenosides Rb on Blood of Tumor Mice

Objective

The blood of cancer patients is in a state of hypercoagulability, easily leading to thrombosis. Anemia is also a complication of tumors. Anemia and thrombosis affect the treatment of tumor patients.

Methods

Ginsenosides Rb were extracted from the stems and leaves of American ginseng using water-saturated ethanol and ethyl acetate in silica gel column. Tumor mice model was established by injecting H₂₂ hepatocellular carcinoma cells into the axilla of mice. Mice were randomly divided into 6 groups: normal control group, model control group, positive control group, low dose group (7 mg/kg), middle dose group (14 mg/kg), and high dose group (35 mg/kg). After 18 days, the blood was obtained by picking the eyeball of mice. The levels of red blood cells (RBC), hemoglobin (HGB), neutrophils/lymphocytes radio (NLR), platelets (PLT), platelet distribution width (PDW), fibrinogen (FIB), and D-Dimer (D-D) were measured and compared in each group of mice.

Results

The content of obtained ginsenosides Rb reached 90.05%. This extraction process was simple and reliable. Middle dose of ginsenosides Rb could significantly increase RBC and HGB levels (P<0.05). Moreover, ginsenosides Rb could significantly reduce NLR, PLT, PDW, FIB, and D-D (P<0.01).

Conclusion

ginsenosides Rb could significantly improve anaemia and hypercoagulation of blood in cancer mice. Ginsenosides Rb are a potential anticoagulant and antianemia drug in treating cancer.

Induction of functional erythropoietin and erythropoietin receptor gene expression by gamma-aminobutyric acid and piperine in kidney epithelial cells

AIMS

The aim of this study was to evaluate gamma-aminobutyric acid (GABA)- and piperine-induced erythropoietin (EPO) and EPO-receptor expression.

MATERIALS AND METHODS

The effect of GABA and piperine on cell viability was examined using kidney epithelial cells. Expression levels of EPO and EPO-R mRNA and protein were evaluated in response to GABA and piperine treatments. GABA- and piperine-mediated activation of the mitogen-activated protein kinase (MAPK) signaling pathway was investigated. Additionally, EPO function was evaluated using conditioned media containing EPO. The GABA receptor type involved in this process was identified.

KEY FINDINGS

Messenger RNA and protein expression levels of EPO and EPO-R significantly increased in response to treatment with GABA, piperine, or the combination of both, compared with control. GABA plus piperine synergistically enhanced EPO and EPO-R expression through p38 and c-Jun N-terminal kinase (JNK) MAPK signaling pathways, but not through the extracellular signal-regulated kinase (ERK) MAPK pathway. SB203580 and SP600125 (p38 and JNK pathway inhibitors, respectively) attenuated GABA plus piperine-induced EPO and EPO-R expression. Treatment of macrophages with EPO-containing conditioned media induced mRNA expression of interleukin (IL)-10 and nuclear factor (NF)-κB due to the interaction between EPO and EPO-R. Interestingly, GABA-induced EPO and EPO-R expression was mediated through GABA_A, not GABA_B, receptor activation.

SIGNIFICANCE

These findings demonstrate that GABA plus piperine-mediated p38 and JNK MAPK activation increases EPO and EPO-R expression, resulting in up-regulation of IL-10 and NF-κB.

Effects of recombinant human erythropoietin on cognition and neural activity in remitted patients with mood disorders and first-degree relatives of patients with psychiatric disorders: a study protocol for a randomized controlled trial

Background

Bipolar disorder (BD) and unipolar disorder (UD) are associated with cognitive deficits and abnormal neural activity in a “cognitive control network.” There is an increased prevalence of cognitive dysfunction in psychiatric patients’ first-degree relatives, which constitutes a risk factor for psychiatric illness onset. However, there is no treatment with enduring pro-cognitive efficacy. We found preliminary evidence for beneficial effects of eight weekly doses of recombinant human erythropoietin (EPO) on cognition in BD in a recent randomized controlled trial (RCT). The present RCT consists of two sub-studies that extend our previous work by investigating important novel aspects: (1) the effects of 12 weekly doses of EPO on cognition in first-degree relatives of patients with BD, UD, or schizophrenia; and (2) the effects of extending the treatment schedule from 8 to 12 weeks in remitted patients with BD or UD; and (3) assessment of early treatment-associated neural activity changes that may predict cognitive improvement.

Methods

The trial comprises two parallel sub-studies with randomized, controlled, double-blinded, parallel group designs. First-degree relatives (sub-study 1; n = 52) and partially or fully remitted patients with BD or UD (sub-study 2; n = 52) with objectively verified cognitive dysfunction are randomized to receive weekly high-dose EPO (40,000 IU/mL) or placebo (saline) infusions for 12 weeks. Assessments of cognition and mood are conducted at baseline, after two weeks of treatment, after treatment completion, and at six-month follow-up. Functional magnetic resonance imaging (fMRI) is conducted at baseline and after two weeks of treatment. Psychosocial function is assessed at baseline, after treatment completion and six-month follow-up. The primary outcome is change in a cognitive composite score of attention, verbal memory, and executive functions. Statistical power of ≥ 80% is reached to detect a clinically relevant between-group difference by including 52 first-degree relatives and 52 patients with BD or UD, respectively. Behavioral data are analyzed with an intention-to-treat approach using mixed models. fMRI data are analyzed with the FMRIB Software Library.

Discussion

If this trial reveals pro-cognitive effects of EPO, this may influence future treatment of mood disorders and/or preventive strategies in at-risk populations. The fMRI analyses may unravel key neurobiological targets for pro-cognitive treatment.

Trial registration

ClinicalTrials.gov, NCT03315897. Registered on 20 October 2017.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2995-7) contains supplementary material, which is available to authorized users.

Erythropoietin as an add-on treatment for cognitive side effects of electroconvulsive therapy: a study protocol for a randomized controlled trial

Background

Electroconvulsive therapy (ECT) is the most effective treatment for severe depression, but its use is impeded by its cognitive side effects. Novel treatments that can counteract these side effects may therefore improve current treatment strategies for depression. The present randomized trial investigates (1) whether short-term add-on treatment with erythropoietin (EPO) can reduce the cognitive side -effects of ECT and (2) whether such effects are long-lasting. Further, structural and functional magnetic resonance imaging (MRI) will be used to explore the neural underpinnings of such beneficial effects of EPO. Finally, the trial examines whether potential protective effects of EPO on cognition are accompanied by changes in markers of oxidative stress, inflammation, and neuroplasticity.

Methods/design

The trial has a double-blind, randomized, placebo-controlled, parallel group design. Patients with unipolar or bipolar disorder with current moderate to severe depression referred to ECT (N = 52) are randomized to receive four high-dose infusions of EPO (40,000 IU/ml) or placebo (saline). The first EPO/saline infusion is administered within 24 h before the first ECT. The following three infusions are administered at weekly intervals immediately after ECT sessions 1, 4, and 7. Cognition assessments are conducted at baseline, after the final EPO/saline infusion (3 days after eight ECT sessions), and at a 3 months follow-up after ECT treatment completion. The neuronal substrates for potential cognitive benefits of EPO are investigated with structural and functional MRI after the final EPO/saline infusion. The primary outcome is change from baseline to after EPO treatment (3 days after eight ECT sessions) in a cognitive composite score spanning attention, psychomotor speed, and executive functions. With a sample size of N = 52 (n = 26 per group), we have ≥ 80% power to detect a clinically relevant between-group difference in the primary outcome measure at an alpha level of 5% (two-sided test). Behavioral, mood, and blood-biomarker data will be analyzed using repeated measures analysis of covariance. Functional MRI data will be preprocessed and analyzed using the FMRIB Software Library.

Discussion

If EPO is found to reduce the cognitive side effects of ECT, this could have important implications for future treatment strategies for depression and for the scientific understanding of the neurobiological etiology of cognitive dysfunction in patients treated with ECT.

Trial registration

ClinicalTrials.gov, NCT03339596. Registered on 10 November 2017.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2627-2) contains supplementary material, which is available to authorized users.

Curcumin analog DM-1 in monotherapy or combinatory treatment with dacarbazine as a strategy to inhibit in vivo melanoma progression

Malignant melanoma is a highly aggressive form of skin cancer with a high mortality rate if not discovered in early stages. Although a limited number of treatment options for melanoma currently exist, patients with a more aggressive form of this cancer frequently decline treatment. DM-1 is a sodium phenolate and curcumin analog with proven anticancer, anti-proliferative and anti-metastatic properties. In this paper, the DM-1 compound showed in vivo antitumor activity alone or in combination with chemotherapeutic DTIC in B16F10 melanoma-bearing mice. Beneficial effects such as melanoma tumor burden reduction with pyknotic nuclei, decreased nuclei/cytoplasmic ratio and nuclear degradation occurred after DM-1 treatment. No toxicological changes were observed in the liver, kidneys, spleen and lungs after DM-1 monotherapy or DTIC combined therapy. DTIC+DM-1 treatment induced the recovery of anemia arising from melanoma and immunomodulation. Both DM-1 treatment alone and in combination with DTIC induced apoptosis with the cleavage of caspase-3, -8 and -9. Furthermore, melanoma tumors treated with DM-1 showed a preferential apoptotic intrinsic pathway by decreasing Bcl-2/Bax ratio. Considering the chemoresistance exhibited by melanoma towards conventional chemotherapy drugs, DM-1 compound in monotherapy or in combination therapy provides a promising improvement in melanoma treatment with a reduction of side effects.

A pilot study to evaluate the safety and clinical outcomes of once-weekly epoetin alfa 80,000 u in anemic patients with cancer receiving chemotherapy

BACKGROUND

Epoetin alfa is indicated for the treatment of chemotherapy-induced anemia at doses of 150 U/kg 3 times weekly or 40,000 U once weekly. Higher starting doses may lead to higher hematologic response rates (RRs), earlier hematologic responses, and earlier identification of nonresponders. The hematologic response and safety of epoetin alfa at a starting dose of 80,000 U once weekly in anemic patients (hemoglobin [Hb] </= 11 g/dL) with nonmyeloid malignancies receiving chemotherapy were evaluated in this open-label, multicenter pilot study.

PATIENTS AND METHODS

Epoetin alfa was initiated at 80,000 U once weekly and reduced if Hb increased to > 13 g/dL or increased > 1.3 g/dL in a 2-week period during the 12-week study. The primary efficacy endpoint was major hematologic response (Hb increase >/= 2 g/dL or Hb >/=12 g/dL, independent of transfusion). Secondary endpoints were minor hematologic response (Hb increase >/= 1 g/dL but > 2 g/dL) and incidence of transfusions.

RESULTS

Of 69 patients enrolled, 47 (68%) completed the study. A majority of patients (72%) exhibited a major hematologic response with epoetin alfa 80,000 U once weekly. Mean Hb levels increased by 2.2 g/dL from baseline after 12 weeks of therapy. Six patients (8.8%) received packed red blood cell transfusions during the study. The dose of epoetin alfa was reduced, or held then reduced, per protocol in 48 patients (69.6%). Ten patients (14.5%) in the safety population experienced a total of 11 clinically relevant thrombotic vascular events.

CONCLUSION

Epoetin alfa at a starting dose of 80,000 U once weekly (with appropriate dose reductions) increased Hb level, was associated with a packed red blood cell transfusion rate > 5% after 4 weeks of therapy, and was safe and generally well tolerated in anemic patients with cancer receiving chemotherapy. The hematologic RR, however, was not markedly improved compared with previous trials with 40,000-60,000 U once weekly, perhaps partly because of the high frequency of dose reductions.

Management of anemia in cancer patients

Cancer-related anemia adversely affects quality of life and is associated with reduced overall survival. The correction of anemia in cancer patients has the potential to improve treatment efficacy and increase survival. A large number of studies demonstrate that treatment of anemia in cancer patients using erythropoiesis-stimulating agents (ESAs) significantly increases hemoglobin levels, decreases transfusion requirements and improves quality of life, predominantly by reducing fatigue. Some data on the use of ESAs in cancer patients indicate an increased risk of thromboembolic events and a possibly increased risk of mortality. However, there is ample evidence that when ESAs are used within current guidelines, they are valuable and safe drugs for the treatment of anemia in patients receiving radiotherapy and/or chemotherapy. There are increasing data from prospective, randomized trials demonstrating better responses to ESAs with the concurrent use of iron. Blood transfusions are also helpful in the management of anemia in cancer patients, especially when there is a need for immediate increases in hemoglobin levels. In this article, we discuss recent aspects relating to treatment modalities for anemia in cancer patients.

Effects of erythropoietin on depressive symptoms and neurocognitive deficits in depression and bipolar disorder

Background

Depression and bipolar disorder are associated with reduced neural plasticity and deficits in memory, attention and executive function. Drug treatments for these affective disorders have insufficient clinical effects in a large group and fail to reverse cognitive deficits. There is thus a need for more effective treatments which aid cognitive function. Erythropoietin (Epo) is involved in neuroplasticity and is a candidate for future treatment of affective disorders. The investigators have demonstrated that a single dose of Epo improves cognitive function and reduces neurocognitive processing of negative emotional information in healthy and depressed individuals similar to effects seen with conventional antidepressants. The current study adds to the previous findings by investigating whether repeated Epo administration has antidepressant effects in patients with treatment resistant depression and reverses cognitive impairments in these patients and in patients with bipolar disorder in remission.

Methods/design

The trial has a double-blind, placebo-controlled, parallel-group design. 40 patients with treatment-resistant major depression and 40 patients with bipolar disorder in remission are recruited and randomised to receive weekly infusions of Epo (Eprex; 40,000 IU) or saline (NaCl 0.9%) for 8 weeks. Randomisation is stratified for age and gender. The primary outcome parameters for the two studies are: depression severity measured with the Hamilton Depression Rating Scale 17 items (HDRS-17) [1] in study 1 and, in study 2, verbal memory measured with the Rey Auditory Verbal Learning Test (RAVLT) [2,3]. With inclusion of 40 patients in each study we obtain 86% power to detect clinically relevant differences between intervention and placebo groups on these primary outcomes.

Trial registration

The trial is approved by the Local Ethics Committee: H-C-2008-092, Danish Medicines Agency: 2612-4020, EudraCT: 2008-04857-14, Danish Data Agency: 2008-41-2711 and ClinicalTrials.gov: NCT 00916552.

Erythropoietin modulates neural and cognitive processing of emotional information in biomarker models of antidepressant drug action in depressed patients

OBJECTIVE

Erythropoietin (Epo) has neuroprotective and neurotrophic effects, and may be a novel therapeutic agent in the treatment of psychiatric disorders. We have demonstrated antidepressant-like effects of Epo on the neural and cognitive processing of facial expressions in healthy volunteers. The current study investigates the effects of Epo on the neural and cognitive response to emotional facial expressions in depressed patients.

METHOD

Nineteen acutely depressed patients were randomized to receive Epo (40,000 IU) or saline intravenously in a double-blind, parallel-group design. On day 3, we assessed neuronal responses to fearful and happy faces using functional magnetic resonance imaging and measured facial expression recognition after the scan.

RESULTS

Epo reduced neural response to fearful vs. happy faces in the amygdala and hippocampus, and to fearful faces vs. baseline in superior temporal and occipitoparietal regions 3 days after administration in acutely depressed patients. This was accompanied by a specific reduction in the recognition of fear in Epo-treated patients after the scan similar to the effects on face recognition seen with antidepressant drug treatment.

CONCLUSIONS

The present findings are similar to the effects of conventional antidepressants in acutely depressed patients and opposite to hypervigilance to negative facial expressions in depression. This highlights a potential antidepressant mechanism and warrants further investigation of Epo as a new candidate compound for treatment of depression.

Treating anemia of cancer with every-4-week darbepoetin alfa: final efficacy and safety results from a phase II, randomized, double-blind, placebo-controlled study

Darbepoetin alfa is an erythropoiesis-stimulating agent (ESA) approved for treating chemotherapy-induced anemia. This phase II, double-blind, placebo-controlled study examined the efficacy of darbepoetin alfa for treating anemia of cancer (AoC) in patients not receiving chemotherapy or radiotherapy. Patients were randomized 3:1 to receive darbepoetin alfa (6.75 microg/kg) or placebo every 4 weeks; the end of the study was at week 17. The primary endpoint was the percentage of patients with a hematopoietic response. Secondary endpoints included transfusion incidence and safety parameters. Efficacy analyses were performed on 162 patients in the darbepoetin alfa group and 56 patients in the placebo group. The Kaplan-Meier percentages of patients who achieved a hematopoietic response (darbepoetin alfa, 69%; placebo, 24%) or achieved the target hemoglobin (darbepoetin alfa, 85%; placebo, 50%) differed significantly between treatment groups. The transfusion incidence did not differ between treatment groups probably because of the low baseline transfusion rates in AoC patients. The incidence of adverse events (including on-study deaths) was similar in both groups. In conclusion, darbepoetin alfa appeared to be well tolerated and significantly increased hemoglobin levels in these AoC study patients.

Effect of epoetin alpha therapy on cognitive function in anaemic patients with solid tumours undergoing chemotherapy

The primary aim of this study was to assess whether epoetin alpha (Ea) would improve cognitive performance in a group of anaemic cancer patients receiving chemotherapy. The secondary aim was to confirm the positive impact of Ea on haematological parameters, and quality of life (QOL). Fifty patients with solid tumours and haemoglobin (Hb) <11.0 g/dL received Ea 40,000 units once weekly for 12 weeks and were administered the Mini-Mental State Examination and the European Organization for Research and Treatment of Cancer (QLQ-C30) questionnaire prior to Ea therapy and at study completion. No clinically significant alterations were observed on cognitive function during Ea treatment. Changes in cognitive function were unrelated to Hb change and there were no significant differences in cognitive performance between Ea responders and non-responders. The analyses revealed clinically significant improvements in Hb levels, physical and role function, and clinically meaningful reductions in fatigue. Hb changes were significantly associated with the magnitude of improvement in QOL parameters. The lack of a clinical benefit in cognition observed in this study during Ea treatment may redirect the focus of research from enhancing to maintaining cognitive function, since stability in cognitive performance through time may be as well clinically important.

Dosing and Outcomes Study of Erythropoiesis-Stimulating Therapies (DOSE) : a registry for characterizing anaemia management and outcomes in oncology patients

BACKGROUND AND OBJECTIVE

To report the design, methodology, implementation and initial results of the Dosing and Outcomes Study of Erythropoiesis-Stimulating Therapies (DOSE) Registry, the first US patient registry to collect and report on practice patterns and outcomes associated with erythropoiesis-stimulating therapy (EST) for anaemia management in oncology patients.

METHODS

DOSE is a prospective ongoing registry of oncology patients treated with epoetin-alpha or darbepoetin-alpha. Patients from either community or academic centres who meet prespecified entry criteria are eligible for inclusion in the registry. Data collected include patient demographic and clinical characteristics, EST administration, haematological parameters, patient-reported outcomes and medical resource utilization. Patients are followed from EST initiation through to the end of therapy or 16 weeks, whichever is earlier.

RESULTS

Initial results from 45 sites for 861 patients (epoetin-alpha, n = 312; darbepoetin-alpha, n = 549) showed that baseline demographic and disease characteristics were similar between the two treatment groups. Administration of EST at both weekly and > or =2-weekly intervals was observed in both groups, with similar numbers of haemoglobin determinations. However, the mean number of office visits was higher in the darbepoetin-alpha group despite more frequent administration of therapy at > or =2-weekly intervals in this group. Mean treatment duration was approximately 8 weeks for both groups. Mean post-baseline haemoglobin levels of 11-12 g/dL were achieved and maintained at all timepoints assessed with epoetin-alpha but not with darbepoetin-alpha. Both groups had similar rates of packed red blood cell transfusions.

CONCLUSIONS

The DOSE Registry is a valuable source of data relating to anaemia management, practice patterns and outcomes in oncology patients from the perspective of actual clinical practice. Results from this registry should provide patients, clinicians and healthcare decision makers with a better understanding of the relationship between EST dosage and outcomes in the clinical setting.

Erythropoietin promotes hepatic regeneration after extended liver resection in rats

BACKGROUND AND AIM

It has been proven in various animal studies that recombinant human erythropoietin (rHuEPO) protects renal, cardiac and neuronal, as well as hepatic, tissue from ischemia, and promotes regeneration of adult central nervous system neurons. To date, no data are available as to whether rHuEPO has the ability to stimulate liver regeneration after liver resection.

METHODS

Rats undergoing 70% or 90% hepatectomy received an intraportalvenous administration (i.p.) of rHuEPO prior to resection or a subcutaneous injection (s.c.) for 3 days postoperatively, control animals were treated with surgery and saline injection only. Regeneration capacity of remnant livers was studied over 7 days by histology and immunohistochemistry (Ki-67, proliferating cell nuclear antigen [PCNA]). Polymerase chain reaction was carried out to measure transforming growth factor beta (TGF-beta), hypoxia induced factor (HIF), signal transducing activator 3 and vascular endothelial growth factor.

RESULTS

Ten-day survival in rats undergoing 90% hepatectomy significantly increased in i.p.-pretreated animals. After 70% hepatectomy the mitotic index was significantly increased in both rHuEPO-treated groups. These data were confirmed by PCNA and Ki-67 expression, which was significantly increased in the treated groups 24 h and 2 days after liver resection. TGF-beta and HIF mRNA both were upregulated in control animals 3 h after surgery.

CONCLUSION

rHuEPO effectively increased liver regeneration in rats after 70% liver resection and enhanced survival after 90% hepatectomy. Thus, rHuEPO may increase the regenerative capacity after major hepatectomy.

Fatigue in Advanced Cancer: A Prospective Study

Fatigue is a common advanced cancer symptom. Clinical features are not well known. The authors surveyed consecutive patients admitted to a palliative medicine program to identify clinical correlates of fatigue. Data collected included age, sex, performance status, primary site, prior chemotherapy/radiation therapy, and blood transfusions. Visual analogue scales assessed fatigue, quality of life, and ability to perform daily activities. Weight change was estimated. Laboratory results including lactate dehydrogenase and hemoglobin were recorded. Fatigue severity was associated with brain metastases, poor performance status, poor quality of life, and reduced ability to perform activities. Prior radiation therapy was associated with less severe fatigue. Age, sex, and hemoglobin level were not associated with fatigue. Fatigue was universal on referral. Brain metastases and poor quality of life independently predicted severity. Hemoglobin level did not predict fatigue. Further studies are necessary to define the clinical features and relationships of fatigue.

Erythropoietin reduces neural and cognitive processing of fear in human models of antidepressant drug action

BACKGROUND

Erythropoietin (Epo) has neuroprotective and neurotrophic effects in animal models and affects cognitive and associated neural responses in humans. These effects have highlighted Epo as a candidate for treatment of psychiatric disease including schizophrenia and depression. The current study aimed to explore the effects of Epo on neural and behavioral measures of emotional processing relevant for depression and the effects of conventional antidepressant medication.

METHODS

In the present study, we used functional magnetic resonance imaging to explore the effects of Epo (40,000 IU) versus saline on the neural processing of happy and fearful faces in 23 healthy volunteers. Facial expression recognition was assessed outside the scanner.

RESULTS

One week after administration, Epo reduced neural response to fearful versus neutral faces in the occipito-parietal cortex consistent with reduced attention to fear. Erythropoietin additionally reduced recognition of fearful facial expressions without affecting recognition of other emotional expressions. These actions occurred in the absence of changes in hematological parameters.

CONCLUSIONS

The present study demonstrates that Epo directly modulates brain responses to emotional information in humans in a manner consistent with the actions of conventional antidepressants. The characterization of the effects of Epo in a clinically depressed group is therefore warranted.

An extended maintenance dosing regimen of epoetin alfa 80,000 U every 3 weeks in anemic patients with cancer receiving chemotherapy

BACKGROUND

The purpose of this study was to evaluate the safety and efficacy of epoetin alfa (EPO) at an initial dose of 60,000 Units (U) once weekly (QW) followed by extended dosing of 80,000 U every 3 weeks (Q3W) in patients with chemotherapy-induced anemia (CIA).

MATERIALS AND METHODS

Anemic patients (hemoglobin [Hb] < or = 11 g/dl) receiving Q3W chemotherapy for nonmyeloid malignancy were enrolled in this prospective, open-label, single-arm study to receive EPO 60,000 U subcutaneously (SC) QW (initial dosing phase [IDP]) until a target Hb level of 12 g/dl was reached (maximum 12 weeks). Patients who achieved an Hb level of 12 g/dl at any point during the IDP then entered the extended dosing phase (EDP; EPO 80,000 U SC Q3W). Maximum study duration (IDP + EDP) was 24 weeks. The primary endpoint was the proportion of patients achieving a hematopoietic response (Hb increase > or = 2 g/dl from baseline or Hb > or = 12 g/dl) during the IDP.

RESULTS

One hundred fifteen patients were enrolled. During the IDP, 76% (84/110) of patients achieved a hematopoietic response, and 15% (17/115) received red blood cell (RBC) transfusion. Sixty-three percent (73/115) of patients entered the EDP, and 88% (64/73) of these patients maintained a mean Hb level > 11.0 and < or =13.0 g/dl. Two of 73 patients received RBC transfusion during the EDP. Adverse events were consistent with the underlying disease and chemotherapy treatment.

CONCLUSION

These results suggest that initiation of EPO 60,000 U SC QW is effective in the treatment of CIA and that EPO 80,000 U SC Q3W can be an effective extended dosing option.

Erythropoietin and treatment of non-anemic conditions--cardiovascular protection

The well-established physiological function of erythropoietin (EPO) is the induction of erythropoiesis. A growing body of evidence indicates that EPO has tissue-protective effects and prevents tissue damage during ischemia and inflammation. Tissue protection after ischemia and injury has been found in the brain, heart, and kidney. It has been speculated that EPO has anti-apoptotic effects in cardiovascular cells. These novel effects of EPO seem to be independent of its erythropoietic activity. Unclear is the role of the known EPO receptor or whether other signaling pathways are involved; a novel EPO receptor might be involved in tissue protection by this hormone. This review article summarizes present knowledge of cardiovascular and renal protective effects of EPO and discusses possible underlying mechanisms.

Pharmacokinetic study of darbepoetin alfa: absorption, distribution, and excretion after a single intravenous and subcutaneous administration to rats

KRN321 is a hyperglycosylated analogue of recombinant human erythropoietin (rHuEPO, epoetin alfa), and its absorption, distribution, and excretion have been studied after a single intravenous and subcutaneous administration of 125I-KRN321 at a dose of 0.5 microg kg-1 to male rats. The half-lives of immunoreactive radioactivity in the terminal phase after intravenous and subcutaneous administration were 14.05 and 14.36 h, respectively, and the bioavailability rate after subcutaneous administration was 47%. The total radioactivity in tissues was lower than that in the serum in all tissues excluding the thyroid gland and skin at the injection site (subcutaneous administration). The maximum concentrations were observed in the bone marrow or skin at the injection site followed by the thyroid gland, kidneys, adrenal glands, spleen, lungs, stomach and bladder. The radioactivity found in trichloroacetic acid-precipitated fractions suggested that a high-molecular weight compound, unchanged or mixed with endogenous protein, distributed to the tissues after administration. The whole-body autoradiographic findings in both groups were in agreement with the tissue distribution mentioned above. The blood cell uptake of KRN321 was low for both groups. The excretion ratios of radioactivity into urine and faeces up to 168 h were 71.4 and 14.1% after the intravenous administration and 74.9 and 12.0% after the subcutaneous administration. There was no difference in the excretion profile of radioactivity between the two groups.

Erythropoietin reduces ischemia-reperfusion injury in the rat liver

BACKGROUND

Human recombinant erythropoietin (Epo) has recently been shown to be a potent protector of ischemic damage in various organ systems. A significant reduction of stroke injury following cerebral ischemia has been postulated as well as improved cardiomyocyte function after myocardial infarction in tissue pretreated with Epo. It was the aim of this study to evaluate the effects of Epo in liver ischemia.

MATERIAL AND METHODS

Rats were subjected to 45 min of warm hepatic ischemia. Animals were either pretreated with 1,000 IU of Epo in three doses or received 1,000 IU into the portal vein 30 min before ischemia. Control animals received saline at the same time points before ischemia. Animals were than sacrificed 6, 12, 24, 48 h and 7 days after surgery and transaminases were measured. Liver specimens were evaluated regarding apoptosis, necrosis and regeneration capacity.

RESULTS

Apoptosis rates were dramatically reduced in animals pretreated with Epo while mRNA of tumor necrosis factor-alpha and STAT-3 were upregulated in all groups. Intraportal venous injection displayed superiority to subcutaneous preconditioning. Transaminases were significantly reduced among the Epo-treated animals after 6 and 12 h.

CONCLUSION

Our data suggests a protective effect of Epo in warm hepatic ischemia and reperfusion injury in the rat.

Incidence of symptomatic deep venous thrombosis with epoetin alfa or darbepoetin alfa treatment of anemia in patients with ovarian or primary peritoneal cancer

OBJECTIVES

Recombinant epoetin alfa and darbepoetin alfa (r-HuEPO) have been shown to be safe and effective treatments for anemia, but recent reports have suggested an increased risk of thromboembolic events when these agents are used to treat chemotherapy-induced anemia among patients with breast or ovarian cancer. We examined the possible risk of such events among patients with ovarian or primary peritoneal carcinomas and chemotherapy-induced anemia.

METHODS

We retrospectively analyzed data over 10 years from women at one hospital with ovarian or primary peritoneal carcinoma and chemotherapy-induced anemia. The incidence and odds ratio for development of deep venous thrombosis, unadjusted and adjusted for baseline differences and risk factors, was assessed between patients who had received r-HuEPO versus no treatment for anemia.

RESULTS

Of the 364 women, 90 had received r-HuEPO and 253 had not. The incidence of deep venous thrombosis was 6.7% in the group that had received r-HuEPO and 5.1% in the group that had not (unadjusted odds ratio, 1.31; 95% confidence interval [CI], 0.48-3.55). After adjustment for differences in age, body-mass index, prior thromboembolic disease or cancer, and tobacco use, the odds ratio for developing deep venous thrombosis with the use of r-HuEPO was 1.35 (95% CI, 0.49-3.75).

CONCLUSIONS

The use of r-HuEPO was not associated with an increased risk of deep venous thrombosis in this population. A randomized trial is needed to further explore this issue and to detail the safety and efficacy of these agents in patients with various other cancers.

Mechanisms of disease: erythropoietin--an old hormone with a new mission?

The major physiological function of erythropoietin is the induction of erythropoiesis. A growing body of evidence indicates, however, that this hormone has tissue-protective effects and prevents tissue damage during ischemia and inflammation. This review article summarizes the present knowledge on the cardiovascular and renal protective effects of erythropoietin and discusses the possible underlying mechanisms.

Management of fatigue in cancer patients

Cancer-related fatigue (CRF) is either a symptom or a syndrome depending on criteria for diagnosis. CRF is present in 20% to 30% of long-term cancer survivors and 80% to 90% during treatment and at the end of life. Assessment requires determining the presence, severity, and interference with daily activities. Different descriptors for fatigue (eg, tiredness, lack of vigor) measure different patient experiences. Associated factors such as depression, pain, insomnia, dyspnea, anemia, and deconditioning worsen CRF and should be treated if present. Associated factors that contribute to the severity of fatigue differ depending on the stage of cancer. Pharmacologic interventions include recombinant erythropoietin, psychostimulants, corticosteroid, anti-inflammatory drugs other than steroids, and L-carnitine. Advances in the management of CRF will require an understanding of the underlying mechanism before target-specific therapies can be developed.

Randomized, open-label comparison of epoetin alfa extended dosing (80 000 U Q2W) vs weekly dosing (40 000 U QW) in patients with chemotherapy-induced anemia

OBJECTIVE

This randomized, open-label, multicenter study compared the efficacy and safety of epoetin alfa (EPO) 80 000 U every 2 weeks (Q2W) to the FDA-approved regimen of 40 000 U weekly (QW) in patients with chemotherapy-induced anemia.

RESEARCH DESIGN AND METHODS

A total of 310 patients with nonmyeloid malignancy and baseline hemoglobin (Hb) <or= 11 g/dL who were scheduled to receive chemotherapy for a minimum of 12 weeks were randomized to EPO Q2W or QW for up to 12 weeks, with dose modification to maintain Hb at approximately 12 g/dL. Efficacy analyses used the per-protocol population (patients who completed the study with a value for Hb change) for the primary endpoint only and the modified intent-to-treat (mITT) population (patients who received study drug and had at least one postbaseline Hb value) for the primary and secondary endpoints.

RESULTS

Analysis of the primary endpoint revealed that the mean change in Hb from baseline to study end was comparable between the Q2W and QW groups in the per-protocol population (1.6 g/dL vs 1.8 g/dL, respectively; treatment difference, -0.2 g/dL; one-sided 95% confidence interval [-0.56, -]); similar results were observed in the mITT population. Among patients on study at Day 29, 9.6% (13/135) and 11.1% (14/126) of patients in the Q2W and QW groups, respectively, received a transfusion between Day 29 and the end of the study (p = 0.709). Dose withholds (21% vs 42%, p < 0.001) and dose reductions (41% vs 59%, p = 0.003) were less common for Q2W than QW. Safety profiles were similar between groups; clinically relevant thrombotic vascular events occurred in 8% of patients in each group. The open-label dosing and the patient attrition rate did not appear to influence overall study results.

CONCLUSIONS

Extended dosing (80 000 U Q2W) and once-weekly dosing (40 000 U QW) of EPO provided comparable safety and efficacy for chemotherapy-induced anemia.

Patients previously transfused or treated with epoetin alfa at low baseline hemoglobin are at higher risk for subsequent transfusion: an integrated analysis of the Canadian experience

BACKGROUND

The introduction of recombinant human erythropoietin to the management of anemia in cancer patients has resulted in significant reductions in allogeneic blood transfusions, while at the same time contributing to improvements in quality of life. A recent meta-analysis of five randomized, placebo-controlled trials with patient-level data revealed that, while epoetin alfa was very effective in reducing transfusions compared with placebo, patients who were pretransfused were twice as likely to subsequently be transfused during epoetin alfa treatment.

METHODS

To further assess the validity of this rather provocative concept, another integrated analysis was conducted with patient-level data from three Canadian trials, with a combined total of 665 patients receiving epoetin alfa treatments for their cancer- and chemotherapy-induced anemia.

RESULTS

Once again, pretransfusion was the most significant baseline predictor of transfusion, with patients that were pretransfused having a significantly greater likelihood of being transfused than their transfusion-naive counterparts. Furthermore, and corroborating previous findings, baseline hemoglobin (Hb) level was again found to be a significant predictor of transfusion, with patients who were treated at a baseline Hb level < 10 g/dl having a higher chance of being transfused than patients in whom epoetin alfa was initiated at baseline Hb levels of 10-11 g/dl. In addition, when the total units transfused in patients receiving epoetin alfa at different baseline Hb levels were analyzed, >85% of the units of blood transfused were received by patients with baseline Hb levels < 10 g/dl.

CONCLUSION

These data strongly suggest that early treatment with epoetin alfa could significantly optimize clinical benefit in reducing the use of transfusion in cancer patients receiving chemotherapy.

Effectiveness of darbepoetin alfa versus epoetin alfa for the treatment of chemotherapy induced anemia in patients with gynecologic malignancies

OBJECTIVE

Chemotherapy induced anemia (CIA) commonly occurs in gynecologic oncology patients. This often leads to treatment with erythropoietic stimulating agents in order to prevent chemotherapy delays, dose modifications and transfusion of red blood cells. Our objective was to determine the subsequent transfusion rates following administration of either darbepoetin alfa or epoetin alfa.

METHODS

A single institution retrospective chart review was performed utilizing patients from January 2003 to September 2004 who received either darbepoetin alfa or epoetin alfa for CIA (Hgb < or = 10.0). Data collection variables included patient demographics, cancer diagnosis, chemotherapy treatment(s), laboratory data, erythropoeisis stimulation data, and transfusions. Sample size calculations were set to detect a 20% transfusion rate difference between the two groups. Chi-square, Fisher exact test and student t tests were used for statistical analysis.

RESULTS

123 patients were eligible for analysis (60 darbepoetin alfa; 62 epoetin alfa). 93% of darbepoetin alfa patients received 200 mg every other week, while 86% of epoetin alfa patients received 40,000 U weekly. The darbepoetin alfa and epoetin alfa groups were similar in respect to age, race, tumor type, histology, previous chemotherapy, number of chemotherapy agents, weeks of erythropoietic stimulation, and baseline serum levels of creatinine and hemoglobin. The mean baseline Hgb and change in Hgb was similar for each group (darbepoetin alfa = 11.2, 2.5 and epoetin alfa = 11.3, 2.3). Twenty one (35%) of the darbepoetin alfa patients received a transfusion of packed red blood cells compared to 12 (19%) of epoetin alfa patients (p = 0.05).

CONCLUSIONS

This retrospective analysis powered to detect differences in transfusion rates revealed a statistically significant difference in transfusion rates between darbepoetin alfa and epoetin alfa for the treatment of CIA. These data warrant a randomized prospective trial in gynecologic oncology patients with careful attention to the timing of initiation of treatment, dosing regimens, and titration of growth factor.

Randomized comparison of epoetin alfa (40,000 U weekly) and darbepoetin alfa (200 microg every 2 weeks) in anemic patients with cancer receiving chemotherapy

This is the first randomized, open-label, multicenter trial designed and powered to directly compare the hemoglobin (Hb) response to epoetin alfa (EPO), 40,000 U once weekly (QW), with that to darbepoetin alfa (DARB), 200 microg every 2 weeks (Q2W), in anemic patients with cancer receiving chemotherapy (CT). Transfusion requirements, quality of life (QOL), and safety also were evaluated. Adults with solid tumors scheduled to receive CT for > or =12 weeks and with baseline Hb < or =11 g/dl were randomized to receive either EPO 40,000 U QW (n = 178) or DARB 200 microg Q2W (n = 180) s.c. for up to 16 weeks. Doses were increased for nonresponders (Hb increase <1 g/dl) after 4 (EPO) or 6 (DARB) weeks, as per National Comprehensive Cancer Network guidelines, and were reduced for a rapid rise in Hb (>1.3 g/dl [EPO] or >1.0 g/dl [DARB] within any 2-week period) or for an Hb level >13 g/dl. The proportion of patients achieving a > or =1-g/dl Hb rise by week 5, the primary end point, was significantly higher with EPO (47.0%) than with DARB (32.5%), and EPO-treated patients achieved a > or =1-g/dl Hb increase significantly earlier than those receiving DARB (median, 35 days versus 46 days). The mean increase in Hb from baseline was significantly higher at weeks 5, 9, 13, and the end of the study with EPO than with DARB. The number of units transfused per patient was significantly lower for the EPO group than for the DARB group. The proportions of patients requiring transfusions, mean QOL improvements, and tolerability profiles were similar in the two groups.

The Association between Anemia and Fatigue in Patients with Advanced Cancer Receiving Palliative Care

BACKGROUND

Fatigue has been reported to be associated with anemia in patients receiving cancer treatment. Treatment of anemia such as erythropoietin has been reported to decrease fatigue in these patients.

OBJECTIVE

To investigate the correlation between anemia and fatigue intensity in patients with advanced cancer receiving palliative care.

METHODS

We reviewed medical charts of 177 consecutive outpatients seen by our palliative care specialists. Information of fatigue intensity and hemoglobin level was collected.

RESULTS

Among 147 (83%) evaluable patients, the median hemoglobin level was 11.6 g/dL (range, 7.5-16.1). Eighty-two (56%) patients had a hemoglobin level 12 g/dL or less, whereas 125 (85%) had 10 g/dL or more. The median fatigue score in patients with a hemoglobin level 10 g/dL or more and 10 g/dL or less was 6 (range, 4-8) and 7 (range, 5-8), respectively (p = 0.048). The median fatigue score in patients with a hemoglobin level 12 g/dL or more and 12 g/dL or less was 6 (range, 4-7) and 6 (range, 4-8), respectively (p > 0.5). Spearman's rank correlation coefficient showed a significant association only between the hemoglobin level and the albumin level (r = 0.52, p < 0.0001). Hemoglobin level did not show a significant correlation with fatigue although there was a trend (p = 0.09). In a multivariate regression analysis of the intensity of fatigue and other clinical variables, three variables remained significant in the reverse elimination analysis: depression (p = 0.0067), albumin level (p = 0.0079), and sensation of well-being (p = 0.0569). The overall explained variance for this model was 0.22.

CONCLUSION

Our findings suggest that anemia is not one of the major contributors to fatigue in patients with cancer receiving palliative care.

Role of c-Kit and erythropoietin receptor in erythropoiesis

Erythropoiesis is regulated by a number of growth factors, among which stem cell factor (SCF) and erythropoietin (Epo) play a non-redundant function. Viable mice with mutations in the SCF gene (encoded by the Steel (Sl) locus), or its receptor gene c-Kit (encoded by the White spotting (W) locus) develop a hypoplastic macrocytic anemia. Mutants of W or Sl that are completely devoid of c-Kit or SCF expression die in utero of anemia between days 14 and 16 of gestation and contain reduced numbers of erythroid progenitors in the fetal liver. Likewise, Epo and Epo receptor (Epo-R)-deficient mice die in utero due to a marked reduction in the number of committed fetal liver derived erythroid progenitors. Thus, committed erythroid progenitors require both c-Kit and Epo-R signal transduction pathways for their survival, proliferation and differentiation. In vitro, Epo alone is capable of generating mature erythroid progenitors; however, a combined treatment of Epo and SCF results in synergistic proliferation and expansion of developing erythroid progenitors. This review summarizes recent advances made towards understanding the signaling mechanisms by which Epo-R and c-Kit regulate growth, survival, and differentiation of erythroid progenitors alone and cooperatively.

Prior red blood cell transfusions in cancer patients increase the risk of subsequent transfusions with or without recombinant human erythropoietin management

Cancer patients often receive transfusions when their hemoglobin concentration falls to dangerously low levels due to chemotherapy or due to the disease itself. The availability of recombinant human erythropoietin (rHuEPO) has significantly reduced transfusion frequencies in cancer patients. However, the predictability of transfusions prior to the use of rHuEPO for future transfusions has not been evaluated. Data from five randomized, double-blind, placebo-controlled trials in cancer patients receiving chemotherapy and epoetin alfa were utilized to calculate the relative risk of subsequent transfusions in patients who were pretransfused. A meta-analysis with patient-level data was used to assess predictors of transfusion. Baseline data from an open-label study were used to compare quality-of-life (QOL) parameters between previously transfused and transfusion-naive patients. The mean relative risks (RR) of exposure to additional transfusion for pretransfused patients on placebo or epoetin alfa were 2.14 (95% confidence interval [CI]: 1.73, 2.65) and 2.51 (95% CI: 1.92, 3.27), respectively, compared with nontransfused patients. Data from the meta-analysis of patients on epoetin alfa showed that pretransfusion was the most significant predictor for subsequent transfusions (parameter estimate = -1.2628, p < 0.0001 from Logistic Regression Analysis). While epoetin alfa was similarly effective in reducing transfusion risks for patients with or without pretransfusions (compared with placebo), those who were pretransfused were more than twice as likely to be subsequently transfused, compared with those not pretransfused. QOL was significantly worse for pretransfused patients than for nontransfused patients, as measured by the Functional Assessment of Cancer Therapy -Anemia and the Linear Analogue Scale Assessment QOL instruments. The results suggest that transfusions prior to epoetin alfa therapy increase the risk of future transfusions, and early treatment with epoetin alfa might reduce the risk of subsequent transfusions.

Paradoxical strategy for treating chronic diseases where the therapeutic effect is derived from compensatory response rather than drug effect

Reversing chronic conditions remains an elusive goal of medicine. The modern medical paradigm based on blocking overactive pathways or augmenting deficient pathways offers symptomatic benefit, but tolerance to therapy can develop and treatment cessation can produce rebound symptoms due to compensatory mechanisms. We propose a paradoxical strategy for treating chronic conditions based on harnessing compensatory mechanisms for therapeutic benefit. Many current drugs may be repurposed for a paradoxical indication where the therapeutic effect is derived from compensatory response, rather than drug effect. For example, although exercise is associated with acute adrenergia, paradoxical downregulation of baseline sympathovagal ratio occurs as a remodeling response. For conditions that manifest chronic sympathetic bias such as cardiovascular diseases, judicious administration of adrenergic agonists may induce compensatory downregulation of baseline sympathovagal ratio. The concept may generalize to many other diseases, especially those involving pathways which exhibit strong homeostatic tendencies such as the neurologic, immune, and endocrine systems. Careful consideration of chronobiologic features is necessary to optimize dosing strategies for modulating compensatory responses, and eccentric dosing schedules, shorter-acting formulations, or pulsatile delivery may be desirable in some cases. To what extent the effect of desensitization to current therapy is mistaken for disease progression in conditions such as diabetes, myopia, depression, and hypertension warrants investigation. The merits of combining behavioral and drug therapies such as diet-insulin therapy for diabetes and exercise-beta-blockade for cardiovascular disease should be revisited since there is a risk for exacerbating the underlying dysfunction. The reduced dynamic range of various environmental experiences and the tendency to revert to the mean through medical intervention, thermoregulation, and other modern lifestyle changes may play under-recognized roles in human diseases. Perhaps alternating agonists and antagonist may exercise the entire dynamic range of pathways and improve health.