The Impact of Iron Overload in Patients with Acute Leukemia and Myelodysplastic Syndrome on Hepatic and Endocrine functions

Ferritin-mediated mitochondrial iron homeostasis is essential for the survival of hematopoietic stem cells and leukemic stem cells

Iron metabolism plays a crucial role in cell viability, but its relationship with adult stem cells and cancer stem cells is not fully understood. The ferritin complex, responsible for intracellular iron storage, is important in this process. We report that conditional deletion of ferritin heavy chain 1 (Fth1) in the hematopoietic system reduced the number and repopulation capacity of hematopoietic stem cells (HSCs). These effects were associated with a decrease in cellular iron level, leading to impaired mitochondrial function and the initiation of apoptosis. Iron supplementation, antioxidant, and apoptosis inhibitors reversed the reduced cell viability of Fth1-deleted hematopoietic stem and progenitor cells (HSPCs). Importantly, leukemic stem cells (LSCs) derived from MLL-AF9-induced acute myeloid leukemia (AML) mice exhibited reduced Fth1 expression, rendering them more susceptible to apoptosis induced by the iron chelation compared to normal HSPCs. Modulating FTH1 expression using mono-methyl fumarate increased LSCs resistance to iron chelator-induced apoptosis. Additionally, iron supplementation, antioxidant, and apoptosis inhibitors protected LSCs from iron chelator-induced cell death. Fth1 deletion also extended the survival of AML mice. These findings unveil a novel mechanism by which ferritin-mediated iron homeostasis regulates the survival of both HSCs and LSCs, suggesting potential therapeutic strategies for blood cancer with iron dysregulation.

Supportive Care for Patients With Myelodysplastic Syndromes

ABSTRACT

Myelodysplastic syndromes are a heterogeneous group of bone marrow disorders characterized by ineffective hematopoiesis, progressive cytopenias, and an innate capability of progressing to acute myeloid leukemia. The most common causes of morbidity and mortality are complications related to myelodysplastic syndromes rather than progression to acute myeloid leukemia. Although supportive care measures are applicable to all patients with myelodysplastic syndromes, they are especially essential in patients with lower-risk disease who have a better prognosis compared with their higher-risk counterparts and require longer-term monitoring of disease and treatment-related complications. In this review, we will address the most frequent complications and supportive care interventions used in patients with myelodysplastic syndromes, including transfusion support, management of iron overload, antimicrobial prophylaxis, important considerations in the era of COVID-19 (coronavirus infectious disease 2019), role of routine immunizations, and palliative care in the myelodysplastic syndrome population.

Iron overload induces islet β cell ferroptosis by activating ASK1/P-P38/CHOP signaling pathway

Background

Recent studies have shown that the accumulation of free iron and lipid peroxides will trigger a new form of cell death-ferroptosis. This form of cell death is associated with a variety of diseases, including type 2 diabetes. We hypothesize that iron overload may play a role in driving glucose metabolism abnormalities by inducing endoplasmic reticulum stress that mediates ferroptosis in islet β cells. In this study, we tested this conjecture from in vivo and in vitro experiments.

Methods

We established a mouse iron overload model by intraperitoneal injection of iron dextrose (50 mg/kg) and an iron overload cell model by treating MIN6 cells with ferric ammonium citrate (640 μmol/L, 48 h) in vitro. The iron deposition in pancreatic tissue was observed by Prussian blue staining, and the pathological changes in pancreatic tissues by HE staining and the protein expression level by pancreatic immunohistochemistry. In the cellular experiments, we detected the cell viability by CCK8 and observed the cellular ultrastructure by transmission electron microscopy. We also used MDA and ROS kits to detect the level of oxidative stress and lipid peroxidation in cells. Western blotting was performed to detect the expression levels of target proteins.

Results

Iron overload induces MIN6 cell dysfunction, leading to increased fasting blood glucose, impaired glucose tolerance, and significantly decreased insulin sensitivity in mice. This process may be related to the ferroptosis of islet β cells and the activation of ASK1/P-P38/CHOP signaling pathway.

A challenging case of an adolescent and young adult patient with high-risk acute lymphoblastic leukemia: the need for a multidisciplinary approach: a case report

Background

Adolescents and young adults diagnosed with acute lymphoblastic leukemia are treated according to pediatric-based regimens to achieve better results. However, implementation of intensive chemotherapy protocols in this age group is associated with increased treatment-related toxicities, affecting almost every organ and system. In this case, the focus of our interest was on rather rare entities: steroid-induced psychosis that seldom develops in children and adolescents, and choroid plexus hemosiderosis, infrequently identified as a first sign of iron overload.

Case presentation

The aim of this paper is to present a challenging case of a 15-year-old Caucasian male patient treated for high-risk acute lymphoblastic leukemia and who experienced various adverse incidents during intensive chemotherapy, thus necessitating a high-quality multidisciplinary approach. Slow minimal residual disease clearance was an additional concerning issue. Induction and re-induction were complicated by steroid-induced hyperglycemia that required multiple-week insulin. During consolidation, acute kidney injury on the basis of chronic kidney disease was verified, demanding subsequent drug dose modifications. By the end of re-induction, after dexamethasone cessation, infrequent steroid-induced psychosis, presented as incoherent speech, aggressive behavior, and mood swings, required intensive psychiatric support. Neurological evaluation of seizures revealed uncommon choroid plexus hemosiderosis by brain magnetic resonance imaging, warranting appropriate selection of iron chelation therapy in the context of preexisting nephropathy. Ultimately, iron deposits of moderate intensity were verified by liver magnetic resonance imaging, while heart tissue remained intact. The early diagnosis and adequate treatment of aforementioned difficult toxicities resulted in complete recovery of the patient.

Conclusions

Treating adolescents with high-risk acute leukemia and multiple therapy-related morbidities remains a challenge, even in the era of extensive and effective supportive therapy. Superior survival rates might be achieved by prompt recognition of both frequent and rarely encountered adverse episodes, as well as well-timed and appropriate management by a well-coordinated multidisciplinary team.

The Superiority of T2*MRI Over Serum Ferritin in the Evaluation of Secondary Iron Overload in a Chronic Kidney Disease Patient: A Case Report

Secondary iron overload is increasingly encountered in chronic kidney disease (CKD) patients because of the frequent use of parenteral iron products, especially in hemodialysis patients. Serum ferritin has been commonly used to monitor iron overload in these patients; however, other conditions can be associated with the high serum ferritin, like infections and inflammatory conditions. Currently, T2*MRI of the heart and liver is the preferred investigation for evaluating liver iron concentration (LIC) and cardiac iron concentration, which reflect the state of iron overload. Few studies observe a positive correlation between serum iron and LIC in CKD patients and postulate that serum ferritin exceeding 290 mcg/L should indicate significant iron overload and necessitates further MRI evaluation. However, here, we present a patient with a history of ESRD for which she underwent renal transplantation twice referred to our clinic due to persistent elevation in serum ferritin level (>1000 mcg/L) for several years. T2*MRI of the heart and liver revealed the absence of iron overload. Our objective of this case is to demonstrate the accuracy of T2*MRI over serum ferritin in evaluating iron overload and questioning the positive correlation between serum ferritin and LIC in CKD patients.

Iron Overload in a Patient with Non-Transfusion-Dependent Hemoglobin H Disease and Borderline Serum Ferritin: Can We Rely on Serum Ferritin for Monitoring in This Group of Patients?

Secondary iron overload is a common complication in the context of hematological diseases, as iron accumulates due to different mechanisms including chronic transfusion, increased gastrointestinal absorption, chronic hemolysis and underlying genetic defects leading to an increase in gastrointestinal absorption of iron. Since the body does not have a mechanism to excrete excess iron, it gets deposited in the heart, endocrine organs, and the liver with the latest being affected less commonly than in primary iron overload disorders like hemochromatosis. Patients with hemoglobin H disease, which is a type of α-thalassemia, are usually transfusion independent, except in occasions where an external stressful factor leads to a drop in hemoglobin and necessitates blood transfusion. Despite this, secondary iron overload is commonly encountered in these patients due to increased gastrointestinal absorption of iron. To avoid the complications associated with iron overload, these patients are usually monitored with serum ferritin, which is an inexpensive widely available method to monitor iron overload. MRI of the liver (Ferriscan) is a more sensitive and specific method to monitor these patients and avoid the long-lasting and sometimes irreversible effect of secondary iron overload. Here we present an interesting case of a patient with hemoglobin H disease, who was monitored with serum ferritin. She had a serum ferritin level considered as a borderline risk for morbidities secondary to iron overload, and an MRI of her liver (Ferriscan) showed significant iron deposition in the liver associated with increased risk of complications secondary to iron overload.

Discrepancy between Serum Ferritin and Liver Iron Concentration in a Patient with Hereditary Hemochromatosis - The Value of T2* MRI

Primary hemochromatosis is an inherited disorder, and the homeostatic iron regulator (HFE) gene C282Y mutation is a common cause of hemochromatosis in Europe. We are reporting a case of a 56-year-old female known to have hemochromatosis with the HFE gene C282Y mutation with a serum ferritin level of 482 μg/L who underwent heart and liver T2* MRI which showed no evidence of iron overload – neither in the heart nor in the liver. This indicates that there is a discrepancy between serum ferritin and liver iron concentration by MRI and the superiority of T2* MRI in diagnosis and follow-up of iron overload in patients with hereditary hemochromatosis.

Iatrogenic Iron Overload in an End Stage Renal Disease Patient

Iron overload is a common complication in patients with chronic renal failure treated with dialysis prior to the availability of recombinant human erythropoietin therapy. Iron overload was the result of hypoproliferative erythroid marrow function coupled with the need for frequent red blood cell transfusions to manage symptomatic anemia. The repetitive use of intravenous iron with or without the use of red blood cell transfusions also contributed to iron loading and was associated with iron deposition in liver parenchymal and reticuloendothelial cells. Here we report a 56-year-old female with end-stage renal failure who underwent kidney transplant twice and found to have iatrogenic iron overload with excess intravenous iron treated conservatively.

Iron Overload in Patients with Chronic Lymphocytic Leukemia Complicated by Autoimmune Hemolytic Anemia: A Case Report

Iron overload is commonly seen in the context of hematological diseases in patients who require frequent transfusions. On the other hand, an association between autoimmune hemolytic anemia complicating chronic lymphocytic leukemia and iron overload is unusual. Here, we report 2 cases of iron overload in patients with a background of chronic lymphocytic leukemia complicated by autoimmune hemolytic anemia. Both patients were found to have a high liver iron concentration on liver MRI (FerriScan). This observation raises the important question about the value of screening for iron overload in this group of patients.

Evaluation of Liver Iron Content by Magnetic Resonance Imaging in Children with Acute Lymphoblastic Leukemia after Cessation of Treatment

Objective

There are a limited number of studies evaluating iron overload in childhood leukemia by magnetic resonance imaging (MRI). The aim of this study was to determine liver iron content (LIC) by MRI in children with acute lymphoblastic leukemia (ALL) who had completed treatment and to compare those values with serum iron parameters.

Materials and Methods

A total of 30 patients between the ages of 7 and 18 who had completed ALL treatment were included in the study. Serum iron parameters (serum iron, serum ferritin [SF], and total iron-binding capacity) and liver function tests were studied. R2 MRI was performed for determining LIC.

Results

Normal LIC was detected in 22 (63.4%) of the cases. Seven (23.3%) had mild and 1 (3.3%) had moderate liver iron deposition. In contrast, severe iron overload was not detected in any of the cases. LIC levels were correlated with the numbers of packed red blood cell (pRBC) transfusions (r=0.637, p<0.001), pRBC transfusion volume (r=0.449, p<0.013), SF levels (r=0.561, p=0.001), and transferrin saturation (r=0.353, p=0.044). In addition, a positive correlation was found between the number of pRBC transfusions and SF levels (r=0.595, p<0.001).

Conclusion

We showed that the frequency of liver iron deposition was low and clinically less significant after the end of treatment in childhood ALL patients. LIC was demonstrated to be related to SF and transfusion history. These findings support that SF and transfusion history may be used as references for monitoring iron accumulation or identifying cases for further examinations such as MRI.