Cooley's original description of beta-thalassaemia major included marked bone deformities as a characteristic feature. These were thought to be due to expansion of haemopoiesis attempting to compensate for the congenital anaemia. Regular blood transfusions from infancy prevents these skeletal problems. Nevertheless, symptoms due to bone disease frequently occur in adult patients. Osteoporosis has not previously been reported as a cause of severe morbidity in thalassaemia major. The present study shows a high prevalence of low bone mass among thalassaemia major patients and analyses the predisposing causes. Bone density scans were performed in 82 patients with transfusion-dependent beta thalassaemia. Factors known to be associated with low bone mass such as gender, endocrine disorders and lifestyle activities, together with factors specific to the thalassaemia and its management, were included in a series of univariate analyses to ascertain any significant associations. 42 (51%) of the patients had severely low bone mass and a further 37 (45%) had low bone mass. The three factors showing a statistically significant association with severely low bone mass were male sex, 24/38 (63%) males had severely low bone mass, compared with 18/44 (41%) females, the lack of spontaneous puberty, 22/32 (69%) who required therapeutic induction of pubertal development had severely low bone mass, compared with 19/47 (40%) with spontaneous puberty and diabetes, 8/10 (80%) diabetic patients had severely low bone mass, compared with 23/56 (41%) with normal glucose tolerance. There was no association between the bone mineral density measurements and the haematological characteristics or treatment details of these patients. Severely low and low bone mass are common findings in patients with beta-thalassaemia major despite optimal transfusion and iron chelation. The associated features suggest that the severely low bone mass is due to endocrine abnormalities, in contrast to the haematological causes of bone disease characteristically seen in untreated thalassaemics.

In the past seven years numerous genes that influence iron homeostasis have been discovered. Dr. Beutler provides a brief overview of these genes, genes that encode HFE, DMT-1, ferroportin, transferrin receptor 2, hephaestin, and hepcidin to lay the groundwork for a discussion of the various clinical forms of iron storage disease and how they differ from one another.In Section I, Dr. Beutler also discusses the types of hemochromatosis that exist as acquired and as hereditary forms. Acquired hemochromatosis occurs in patients with marrow failure, particularly when there is active ineffective erythropoiesis. Hereditary hemochromatosis is most commonly due to mutations in the HLA-linked HFE gene, and hemochromatosis clinically indistinguishable from HFE hemochromatosis is the consequence of mutations in three transferrin receptor-2 gene. A more severe, juvenile form of iron storage disease results from mutations of the gene encoding hepcidin or of a not-yet-identified gene on chromosome 1q. Autosomal dominant iron storage disease is a consequence of ferroportin mutations, and a polymorphism in the ferroportin gene appears to be involved in the African iron overload syndrome.Evidence regarding the biochemical and clinical penetrance of hemochromatosis due to mutations of the HFE gene is rapidly accumulating. These studies, emanating from several centers in Europe and the United States, all agree that the penetrance of hemochromatosis is much lower than had previously been thought. Probably only 1% of homozygotes develop clinical findings. The implications of these new findings for the management of hemochromatosis will be discussed.In Section II, Dr. Victor Hoffbrand discusses the management of iron storage disease by chelation therapy, treatment that is usually reserved for patients with secondary hemochromatosis such as occurs in the thalassemias and in patients with transfusion requirements due to myelodysplasia and other marrow failure states. Tissue iron can be estimated by determining serum ferritin levels, measuring liver iron, and by measuring cardiac iron using the MRI-T2* technique. The standard form of chelation therapy is the slow intravenous or subcutaneous infusion of desferoxamine. An orally active bidentate iron chelator, deferiprone, is now licensed in 25 countries for treatment of patients with thalassemia major. Possibly because of the ability of this compound to cross membranes, it appears to have superior cardioprotective properties. Agranulocytosis is the most serious complication of deferiprone therapy and occurs in about 1% of treated patients. Deferiprone and desferoxamine can be given together or on alternating schedules. A new orally active chelating agent ICL 670 seems promising in early clinical studies.In Section III, Dr. James Cook discusses the most common disorder of iron homeostasis, iron deficiency. He will compare some of the standard methods for identifying iron deficiency, the hemoglobin level, transferrin saturation, and mean corpuscular hemoglobin and compare these with some o...

Patients with ␤-thalassemia major (TM) and other refractory anemias requiring regular blood transfusions accumulate iron that damages the liver, endocrine system, and most importantly the heart. The prognosis in TM has improved remarkably over the past 10 years. This improvement has resulted from the development of magnetic resonance imaging (MRI) techniques, especially T2*, to accurately measure cardiac and liver iron, and from the availability of 3 iron-chelating drugs. In this article we describe the use of MRI to determine which adult and pediatric patients need to begin iron chelation therapy and to monitor their progress. We summarize the properties of each of the 3 drugs, deferoxamine (DFO), deferiprone (DFP), and deferasirox (DFX), including their efficacy, patient acceptability, and side effects. We describe when to initiate or intensify therapy, switch to another drug, or use combined therapy. We also discuss the management of refractory anemias other than TM that may require multiple blood transfusions, including sickle cell anemia and myelodysplasia.

The association of MRD test results and DFS was independent of and greater than other standard predictors of outcome and is therefore important in determining treatment for individual patients.

Summary The predictive value of molecular minimal residual disease (MRD) monitoring using polymerase chain reaction amplification of clone‐specific immunoglobulin or T‐cell Receptor rearrangements was analysed in 161 patients with non T‐lineage Philadelphia‐negative acute lymphoblastic leukaemia (ALL) participating in the UK arm of the international ALL trial UKALL XII/Eastern Cooperative Oncology Group (ECOG) 2993. MRD positivity (≥10−4) in patients treated with chemotherapy alone was associated with significantly shorter relapse‐free survival (RFS) at several time‐points during the first year of therapy. MRD status best discriminated outcome after phase 2 induction, when the relative risk of relapse was 8·95 (2·85–28·09)‐fold higher in MRD‐positive (≥10−4) patients and the 5‐year RFS 15% [95% confidence interval (CI) 0–40%] compared to 71% (56–85%) in MRD‐negative (<10−4) patients (P = 0·0002) When MRD was detected prior to autologous stem cell transplantation (SCT), a significantly higher rate of treatment failure was observed [5‐year RFS 25% (CI 0–55%) vs. 77% (95% CI 54–100%) in MRD‐negative/<10−4, P = 0·01] whereas in recipients of allogeneic‐SCT in first complete remission, MRD positivity pre‐transplant did not adversely affect outcome. These data provide a rationale for introducing MRD‐based risk stratification in future studies for the delineation of those at significant risk of treatment failure in whom intensification of therapy should be evaluated.

The p53 protein plays a key role in securing the apoptotic response of chronic lymphocytic leukemia (CLL) cells to genotoxic agents. Transcriptional induction of proapoptotic proteins including Puma are thought to mediate p53-dependent apoptosis. In contrast, recent studies have identified a novel nontranscriptional mechanism, involving direct binding of p53 to antiapoptotic proteins including Bcl-2 at the mitochondrial surface. Here we show that the major fraction of p53 induced in CLL cells by chlorambucil, fludarabine, or nutlin 3a was stably associated with mitochondria, where it binds to Bcl-2. The Puma protein, which was constitutively expressed in a p53-independent manner, was modestly upregulated following p53 induction. Pifithrin ␣, an inhibitor of p53-mediated transcription, blocked the up-regulation of Puma and also of p21 CIP1 . Surprisingly, pifithrin ␣ dramatically augmented apoptosis induction by p53-elevating agents and also accelerated the proapoptotic conformation change of the Bax protein.

The association of MRD test results and DFS was independent of and greater than other standard predictors of outcome and is therefore important in determining treatment for individual patients.

IntroductionOnce thought to be a benign disease, chronic lymphocytic leukemia (CLL) is now known to comprise an aggressive subset, characterized by unmutated immunoglobulin heavy-chain variable (IGHV) genes, high expression of cell-surface CD38, and of the protein tyrosine kinase, zeta-chain-associated protein kinase 70 . 1 The proliferative compartment in CLL is located in "pseudofollicles" within bone marrow and lymphoid tissue, 2 and access of CLL cells to these compartments is dependent on migratory chemokine signals, including chemokine (C-X-C motif) ligand 12 (CXCL12), 2 chemokine (CC motif) ligand 19 (CCL19), and CCL21. 3 CLL is treated with chlorambucil or fludarabine, but is incurable by chemotherapy alone. 4 Because drug resistance is a formidable obstacle to treatment, it is important to identify and evaluate the mechanisms that contribute to apoptosis resistance in CLL and to develop strategies to overcome them.Conventional DNA-damaging cytotoxic agents, including fludarabine and chlorambucil, kill CLL cells via the induction of the proapoptotic p53 protein. 5 Therefore, mutations or deletions affecting the p53 genes are a major cause of drug resistance. 6 However, genetic changes involving p53 are selected for during treatment, and this type of resistance is acquired over time. 6 In contrast, environmental factors mediate drug resistance from the initiation of treatment, resulting in the protection of tumor cells from diverse chemotherapeutic agents and in the survival of foci of residual disease. 2,7 It is therefore desirable to develop strategies that can be applied during initial treatment and are designed to minimize the survival of malignant cells and the consequent emergence of acquired resistance.CLL cells, especially those located in bone marrow or lymphoid tissue, are exposed to extracellular signals that promote their survival and proliferation through the suppression of apoptotic pathways. 2 Interleukin-4 (IL-4) is a Th2 lymphokine that signals via receptor-mediated activation of the Janus protein tyrosine kinases, JAK1 and JAK3, and subsequent phosphorylation and activation of the signal transducer and activator of transcription 6 (STAT6) transcription factor. 8 IL-4 prolongs the basal survival of CLL cells in vitro, 9 and the IL-4 receptor is abundantly expressed by CLL cells, compared with normal B lymphocytes, correlating with the substantially greater antiapoptotic effect of IL-4 on CLL cells. 10,11 Extensive evidence suggests that IL-4/CLL interactions occur in vivo as well. First, an IL-4-secreting CD3 ϩ /CD8 ϩ /CD28 Ϫ T-lymphoid population is expanded in CLL. 12 Second, CLL cells secrete IL-6, which switches T lymphocytes from a T-helper 1 (Th1)-to an IL-4-secreting Th2 phenotype. 13 Third, 40%-65% of CD8 ϩ T cells of CLL patients contained IL-4, while Ͻ 10% of these cells from normal subjects did so. 14 These T cells were also able to secrete IL-4 without activation. Fourth, the proportion of IL-4-positive T cells was greater in patients with progressive disease, compared with st...