Impact of individualized treatment on recovery from fatigue and return to work in survivors of advanced-stage Hodgkin's lymphoma: results from the randomized international GHSG HD18 trial.

BACKGROUND: Persisting cancer-related fatigue impairs health-related quality of life (HRQoL) and social reintegration in patients with Hodgkin's lymphoma (HL). The GHSG HD18 trial established treatment de-escalation for advanced-stage HL guided by positron emission tomography after two cycles (PET-2) as new standard. Here, we investigate the impact of treatment de-escalation on long-term HRQoL, time to recovery from fatigue (TTR-F), and time to return to work (TTR-W). PATIENTS AND METHODS: Patients received European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30 (EORTC QLQ-C30) and life situation questionnaires at baseline, interim, end of treatment, and yearly follow-up. TTR-F was defined as time from the end of chemotherapy until the first fatigue score <30. TTR-W was analyzed in previously working or studying patients and measured from the end of treatment until the first documented work or education. We compared duration of treatment on TTR-F and TTR-W using Cox proportional hazards regression adjusted for confounding variables. RESULTS: HRQoL questionnaires at baseline were available in 1632 (83.9%) of all randomized patients. Overall, higher baseline fatigue and age were significantly associated with longer TTR-F and TTR-W and male sex with shorter TTR-W. Treatment reduction from eight to four chemotherapy cycles led to a significantly shorter TTR-F [hazard ratio (HR) 1.41, P = 0.008] and descriptively shorter TTR-W (HR 1.24, P = 0.084) in PET-2-negative patients. Reduction from six to four cycles led to non-significant but plausible intermediate accelerations. The addition of rituximab caused significantly slower TTR-F (HR 0.70, P = 0.0163) and TTR-W (HR 0.64, P = 0.0017) in PET-2-positive patients. HRQoL at baseline and age were the main determinants of 2-year HRQoL. CONCLUSIONS: Individualized first-line treatment in patients with advanced-stage HL considerably shortens TTR-F and TTR-W in PET-2-negative patients. Our results support the use of response-adapted shortened treatment duration for patients with HL.

[Nonsymptomatic leukocytosis]. / Leukozytose ohne weitere Symptome. Im Zweifelsfall ein Differenzialblutbild.

Leukocytosis is a condition often met with in the clinical and ambulatory setting. Although it is usually caused by an increase in the numbers of neutrophilic granulocytes, an increase in other leukocytes populations may also account for leukocytosis. Etiologically, both primary pathological conditions affecting the white blood cells, such as various forms of leukemia and lymphomas, and also rare genetic disorders must be considered. Decidedly more common, however, are reactive changes caused by infections, cigarette smoking, chronic inflammation, necrotic tissue or certain drugs. Although moderate leukocytosis in the absence of a clinical correlate and/or an apparent trigger, requires no diagnostic clarification, it should be kept under observation. If the etiology is uncertain, or a treatment-requiring disorder is suspected, the differential blood count is at the focus of the further diagnostic work-up. Depending upon the findings, this is supplemented by additional laboratory parameters, bone marrow examination, microbiological investigations and imaging procedures. Leukostasis resulting from vasoocclusion in the presence of very high numbers of leukocytes represents an emergency situation, and is an indication for leukapheresis.

[Elevated Hemoglobin--polyglobulia or polycythemia?]. / Zu viele Erythrozyten. Wie Sie eine Polyglobulie von der Polyzythämie abgrenzen.

An increase in Hb levels, haematocrit or the absolute number of red blood cells may be evidence of polycythemia rubra vera. Much more commonly, however, erythrocytosis is due to an underlying non-hematological disease. To establish the diagnosis of polycythemia, a secondary polyglobulia must first be excluded. If no evidence of polyglobulia is found, or if EPO levels are decreased, or splenomegaly not accountable for by portal hypertension is present, a specific diagnostic work-up must be performed by a hematologist/oncologist. This includes a bone marrow aspiration, cytological examination and molecular genetic testing.

[Fortuitous finding: thrombocytopenia and thrombocytosis]. / Zufallsbefunde Thrombozytopenie und Thrombozytose. Wann müssen Sie aktiv werden?

Thrombocytopenia is present when the number of platelets drops to below 150 G/l. Leaving aside pseudothrombocytopenia, such a situation may be triggered by pregnancy or a range of different drugs, or may signify the presence of idiopathic thrombocytopenic purpura (ITP). Thrombocytosis is present when the platelet count exceeds 500 G/l. This condition includes a large variety of forms of reactive thrombocytosis, a clonal increase in thrombocytes in hematological diseases, and the rare condition of familial thrombocytosis.

GPR56 contributes to the development of acute myeloid leukemia in mice.

The G protein-coupled receptor 56 (GPR56) was identified as part of the molecular signature of functionally validated leukemic stem cells isolated from patients with acute myeloid leukemia (AML). This report now demonstrates particularly high expression of GPR56 in patients with mutant NPM1 and FLT3-length mutation and association of high GPR56 expression with inferior prognosis in a large patient cohort treated in two independent multicenter phase III trials. Functional relevance of GPR56 expression was validated in mice, in which co-expression of Gpr56 significantly accelerated HOXA9-induced leukemogenesis and vice versa knockdown of Gpr56 delayed onset of HOXA9/MEIS1-induced AML. Overexpression of Gpr56 grossly changed the molecular phenotype of Hoxa9-transduced cells affecting pathways involved in G protein-coupled receptors (GPRCs) and associated intracellular signaling. Blockage of surface GPR56 by an anti-GPR56 antibody successfully impaired engraftment of primary human AML cells. In summary, these data demonstrate that high expression of GPR56 is able to contribute to AML development and characterize the GPR56 as a potential novel target for antibody-mediated antileukemic strategies.

Towards a pathogenesis-oriented therapy of acute myeloid leukemia.

Genetic and molecular techniques have provided increasing insights into the biology of acute myeloid leukemia (AML). These investigations showed that AML is not a homogeneous disease but a heterogeneous group of biologically different subentities. These subentities are currently primarily defined by cytogenetics by which three main subgroups can be discriminated: AML with balanced translocations, AML with unbalanced aberrations and AML without cytogenetically detectable aberrations. Within the latter group molecular alterations are identified in more than half of cases such as NPM mutations, FLT3 mutations, MLL duplications and mutations of CEBP-alpha. The clinical meaning of these findings is illustrated by substantial differences in response to therapy and long-term outcome. As demonstrated by the recent multicenter trial of the German AML Cooperative Group (AMLCG) and other studies intensification of induction therapy may improve the results in distinct subtypes but fails to do so in others. Therefore, new strategies need to be explored which incorporate the knowledge about the biology of AML to develop biology adapted treatment strategies. This process has just begun and is predominantly determined by the availability of new agents and their evaluation in clinical phase I and II studies. A variety of targets are currently explored and some trials have yielded promising results already. The step towards a biology adapted treatment of AML is long and requires the combined efforts of researchers, clinicians and the pharmaceutical industry. The first steps towards this goal have been taken and give rise to the hope for more effective and more specific therapies of AML.

Clonal chromosomal abnormalities in the stem cell compartment of patients with acute myeloid leukemia in morphological complete remission.

Acute myeloid leukemia arises from the clonal expansion of a malignant transformed progenitor cell. Despite intensive chemotherapy, final disease eradication is achieved by a small proportion of cases only and 50-70% of adults with AML will ultimately relapse and die from their disease. Hence residual disease below the level of morphological detectability must be assumed in clinical and morphological complete remission. CD34+/CD38- and CD34+/CD38+ subpopulations of seven patients in morphological complete remission were isolated by FACS (purity >98%) and were analyzed by conventional cytogenetics or FISH for chromosomal aberrations. In five of seven patients, clonal chromosomal abnormalities were detected in the CD34+/CD38+ subpopulation and in one patient with AML M2 (add (2)(q37)) in the most immature CD34+/CD38- stem cell compartment. One patient with AML M4Eo (inv(16),+8), showed a normal karyotype by conventional cytogenetic analysis, whereas four of 15 metaphases of the sorted CD34+/CD38+ subpopulation revealed the inversion 16. These observations underline that leukemic cells can survive intensive chemotherapy in the niche of the stem cell compartment. In some patients the sensitivity for the detection of persistent leukemic cells seems to be higher in FACS-sorted subpopulations than conventional cytogenetic analysis of the unseparated bone marrow. Immunophenotyping revealed minimal residual disease in four of the patients. Functional analysis has to be performed to investigate the leukemogenic potential of these residual cells.

Trisomy 4 in 'stem cell-like' leukemic cells of a patient with AML.

CD34 positive progenitor cells were analyzed in the bone marrow aspirate from a patient with newly diagnosed AML FAB M4. The patient had trisomy 4 as sole cytogenetic abnormality and a dominant population of CD34 negative leukemic blasts. Karyotyping of the FACS isolated, minor subpopulation of CD34+/CD38-, 'stem cell'-like cells (incidence 0.29%) revealed trisomy 4 in 11/13 metaphases. No metaphases were obtained in the CD34 negative subpopulation. The experiments point to the existence of leukemic stem cells in the CD34+/CD38- compartment in AML patients with trisomy 4.

Improved engraftment of human acute myeloid leukemia progenitor cells in beta 2-microglobulin-deficient NOD/SCID mice and in NOD/SCID mice transgenic for human growth factors.

Primitive malignant progenitors defined as nonobese diabetic/severe combined immunodeficient (NOD/SCID) leukemia-initiating cells or NOD/SL-IC from patients with acute myeloid leukemia (AML) can be detected and quantitated in sublethally irradiated NOD/SCID mice. However, there is variability in the levels of bone marrow (BM) engraftment obtained after intravenous injection of cells from different AML samples. In the current study, AML cell engraftment in standard NOD/SCID mice was compared to that obtained with NOD/SCID mice transgenic for the human growth factor genes Steel factor (SF), interleukin-3 (IL-3) and granulocyte macrophage-colony-stimulating factor (GM-CSF) (N/S-S/GM/3) as well as beta 2 microglobulin-null NOD/SCID (N/S-beta 2m(-/-)) mice. Three of the eight AML samples that failed to engraft in standard NOD/SCID animals showed easily detectable and up to 70-fold increased in the number of leukemic cells in BM 8-12 weeks post-transplantation in each of the N/S-beta 2m(-/-) and N/S-S/GM/3 mouse strains. In two of the four AML samples studied at limiting dilution, the frequency of NOD/SL-IC detected was increased six- and seven-fold. Thus, in these novel mouse strains a broader spectrum of AML patient samples can be evaluated for their progenitor content and potentially studied for their response to innovative therapeutics in vivo.

Cytogenetic analysis of CD34+ subpopulations in AML and MDS characterized by the expression of CD38 and CD117.

It has been supposed in de novo AML that malignant transformation occurs at the level of committed progenitors. Recent data of our group and others provide evidence that in AML malignant transformation may regularly occur at the level of stem cells. These cells can be discriminated by function and specific surface molecules. CD34, a glycophosphoprotein, is a cellular surface antigen characteristically expressed by stem cells. CD34+ stem cells can be further subdivided by the expression of additional surface molecules like CD38 and CD117. In this article we present results from cytogenetic examinations of FACS-isolated stem cell subpopulations in eight patients (four AML and four MDS). Six of them displayed clonal karyotype abnormalities at the time of first diagnoses in the native bone marrow (5q-; 5q- and complex abnormalities; +8; inv(16) and +8; i(17q) and -21; i(21q)). We used CD117, the receptor for the stem cell factor (also KIT oncogene) as a new cellular surface marker. CD34+/CD117+/- stem cell subpopulations were examined in two patients with AML and three patients with MDS. We found leukemic stem cells in every type of stem cell subpopulation examined (CD34+/CD38-, CD34+/CD38+, CD34+/CD117-, CD34+/CD117+). Secondary, progression-associated chromosome abnormalities likewise were demonstrable in CD34+ cells. In three patients a mosaic of normal and abnormal metaphases was found in the highly purified stem cell subpopulations. We conclude that in AML and MDS stem cells are the target of leukemogenic genetic defects. CD117 as a new marker to isolate different CD34+ subpopulations was not sufficient to discriminate between normal and leukemic stem cells. Our findings have implications for autologous stem cell transplantation, high-dose chemotherapy and the pathogenetic concept of leukemogenesis.

TGF-beta inhibits growth and induces apoptosis in leukemic B cell precursors.

The uncontrolled proliferation of malignant lymphoblasts is the pathobiological hallmark in B cell precursor-ALL (BCP-ALL). Identification of inhibitory growth factors is of great importance for the understanding of growth control of leukemic B cell precursors and the development of novel therapeutic approaches in BCP-ALL. The aim of our study was the analysis of the effect of TGF-beta on cell survival and apoptosis of B cell precursors (BCP) from patients with acute lymphoblastic leukemia in vitro. Experiments were performed in a coculture system with cloned murine fibroblasts, which efficiently block spontaneous ex vivo apoptosis of BCP and thus allows the assessment of cytokine-induced growth inhibition. TGF-beta significantly reduced cell viability of highly purified, FACS isolated CD10+/CD19+ leukemic BCP by a mean of 53% (P = 0.0001). The loss of cell viability was accompanied by a significant increase of apoptosis with a mean of 70% (P = 0.0028). The TGF-beta effect was blocked specifically by a monoclonal anti-TGF-beta antibody. Induction of apoptotic cell death by TGF-beta was not accompanied by reduction of bcl-2 protein expression. TGF-beta transcription was not detected in the leukemic pre-B cell line BLIN-1, but in the murine fibroblasts. The growth inhibitory effect of TGF-beta was not restricted to leukemic BCP. The cytokine also increased apoptosis of normal, highly purified BCP by a mean of 58%. The data identify TGF-beta as a potent growth inhibitory cytokine for leukemic BCP.

In vitro activation of low-grade non-Hodgkin's lymphoma by murine fibroblasts, IL-4, anti-CD40 antibodies and the soluble CD40 ligand.

The in vitro analysis of growth regulation in low-grade B non-Hodgkin's lymphoma (B-NHL) is hampered by the rapid apoptotic death of the malignant B cells ex vivo. A complex culture system, using murine CDw32 transfected fibroblasts (LTK-cells), IL-4 and anti-CD40 mAb, has been established for the propagation of normal mature B cells in vitro. We investigated the influence of the different components of this coculture system on cell survival and apoptosis of B-NHL cells. Nine samples from patients with follicular lymphoma and from eight patients with immunocytoma were analyzed. No cell proliferation of B-NHL cells could be induced in the culture system. However, CDw32-transfected murine fibroblasts most efficiently supported cell viability of B-NHL cells with an increase in cell survival by 114% compared to the control (P = 0.047). IL-4 alone also had a stimulatory effect on cell survival of B-NHL cells after 6 days. In contrast, the soluble recombinant CD40 ligand gp39 and the anti-CD40 mAbs mAb89 and EA-5 did not prolong cell survival. CDw32 transfectants blocked apoptosis of B-NHL cells efficiently from 67% in the control to 16% (P = 0.001). Reduction in apoptosis was accompanied by an elevated bcl-2 protein expression. IL-4 or mAb89 did not further reduce apoptotic cell death in CDw32 transfectant-dependent cocultures. Our data underline the pivotal role of LTK- cells for cell survival of B-NHL cells in vitro. The efficient blockage of apoptosis associated with increased bcl-2 protein expression causes prolonged cell viability of the B-NHL cells.

Variable cytotoxicity of diphtheria toxin 388-granulocyte-macrophage colony-stimulating factor fusion protein for acute myelogenous leukemia stem cells.

In this study, the utility of DT388-granulocyte-macrophage colony-stimulating factor (GM-CSF) for the ex vivo purging and direct administration to patients with acute myeloid leukemia (AML) is tested using clonogenic assays, long-term cultures (LTC), and NOD/SCID mice as assays for leukemic progenitors. We compare the ability of 24-hour exposure to 0.3 microg/mL (4 nM) DT388-GM-CSF to kill AML colony forming cells (CFC) and the more primitive AML progenitors detected after 6 weeks in stromal cocultures (AML LTC-initiating cells or AML LTC-IC) and after 8 weeks in NOD/SCID mice.AML samples (n = 10), expressing a mean of 35 to 1466 GM-CSF receptors/blast, showed mean (range) percent kills of AML CFC and LTC-IC of 61 (17-98) and 46 (0-94) respectively with a direct correlation (r = 0.69) between the % kills detected in the in vitro assays. Among 5 evaluable samples the percent reduction in AML cell engraftment in NOD/SCID marrow following ex vivo DT388-GM-CSF treatment varied from 38% to 100%. 40% to 56% of normal bone marrow CFC and 31% to 48% of normal LTC-IC survived the same ex vivo treatment (n = 3). In subsequent experiments, NOD/SCID mice received AML blast cell injections intravenously followed in 24 hours by 1.5 microg DT388-GM-CSF daily intraperitoneally for 5 days. A reduction of marrow blast cells was seen with 7 of 9 samples tested 4 to 12 weeks post one course of toxin. Repeating the 5-day course of toxin 2 or 3 times at 4-week intervals did not improve the response, while delaying administration until 4 to 8 weeks post AML cell injection reduced the toxin's effectiveness (n = 5).This fusion toxin may prove useful for in vitro purging of stem cell harvests from selected AML patients and for direct administration to such patients.

TGF-beta and its receptor complex in leukemic B-cell precursors.

Transforming growth factor beta (TGF-beta) is a highly conserved peptide with growth-inhibitory activity in multiple normal and transformed cell types. Signal transduction is mediated through the receptor complex, consisting of two active seronine or threonine kinases (TGF-beta-receptor I and II) and the receptor-associated proteins betaglycan (TGF-beta-receptor III) and endoglin. In this study, we assessed the analysis of the role of TGF-beta and the transcription of the genes for TGF-beta and its receptor in highly purified leukemic B-cell precursors (BCPs) of patients with common acute lymphoblastic leukemia (cALL). Leukemic BCPs were positive for gene transcription of TGF-beta (9/9), the TGF-beta-receptor I (9/9), the TGF-beta-receptor II (6/6), betaglycan (5/6), and endoglin (6/6). Incubation with TGF-beta significantly reduced the cell viability of leukemic BCPs by a mean of 45% (p = 0.0009). The reduction of cell viability was associated with the induction of apoptosis by a mean of 31%. TGF-beta caused significant suppression of the S phase (p = 0.002) and accumulation in the G0/G1 phase (p = 0.0005). It also reduced expression of the adhesion surface receptor CD18 and the Fas antigen CD95 from 58% to 40% and from 48% to 27%, respectively. The data indicate that TGF-beta is a negative growth signal in leukemic BCPs and point to an additional role of TGF-beta as an immunomodulatory cytokine, suggesting a complex role of TGF-beta in the leukemogenesis of cALL.

Monoclonal antibody therapy for B cell non-Hodgkin's lymphomas: emerging concepts of a tumour-targeted strategy.

Although much progress has been made in the understanding of the pathobiology of malignant lymphomas in recent years, progress in the treatment of patients with this diagnosis has been limited. Monoclonal antibody therapy is an innovative and promising concept in the treatment of malignant lymphoma, and the current status of this treatment is reviewed here. Phase I/II clinical trials have proven the high antilymphoma activity of antibody-based therapeutic strategies. Radioimmunoconjugates with myeloablative activity have induced response rates of between 80 and 100% in heavily pretreated patients. The chimeric monoclonal antibody IDEC-C2B8 has shown high antilymphoma activity in patients with relapsed follicular lymphoma with an overall response rate of up to 50%. The combination of the IDEC-C2B8 antibody with standard chemotherapy has shown encouraging results with no increase in toxicity compared with chemotherapy alone. The introduction of antibody therapy promises to open new perspectives in the treatment of patients with malignant lymphoma. Prospective randomised clinical trials will define the patient who will gain maximal benefit from antibody-based therapy.

The leukemogenicity of Hoxa9 depends on alternative splicing.

Although the transforming potential of Hox genes is known for a long time, it is not precisely understood to which extent splicing is important for the leukemogenicity of this gene family. To test this for Hoxa9, we compared the leukemogenic potential of the wild-type Hoxa9, which undergoes natural splicing, with a full-length Hoxa9 construct, which was engineered to prevent natural splicing (Hoxa9FLim). Inability to undergo splicing significantly reduced in vivo leukemogenicity compared to Hoxa9-wild-typed. Importantly, Hoxa9FLim could compensate for the reduced oncogenicity by collaborating with the natural splice variant Hoxa9T, as co-expression of Hoxa9T and Hoxa9FLim induced acute myeloid leukemia (AML) after a comparable latency time as wild-type Hoxa9. Hoxa9T on its own induced AML after a similar latency as Hoxa9FLim, despite its inability to bind DNA. These data assign splicing a central task in Hox gene mediated leukemogenesis and suggest an important role of homeodomain-less splice variants in hematological neoplasms.

[Modern leukemia diagnosis in adults]. / Moderne Leukämiediagnostik beim Erwachsenen.

Identification of numerous criteria important in the pathogenesis, biology, prognosis and treatment of the different types of leukemia necessitates a broad spectrum of diagnostic methods for the initial diagnosis and in the further course of the disease. In addition to cytomorphology with cytochemistry, which is been path-breaking for the application of further diagnostic methods, cytogenetics has become an obligatory diagnostic tool. Immunophenotyping and, even more relevant, molecular genetics plays an important role. Other diagnostic techniques are widely developed. The diagnostic procedures are described, with a focus on their mode of operation as well as their clinical significance. Because of their high clinical relevance and growing complexity, the diagnosis of leukemias should be performed in specialized laboratories.

The homeobox gene CDX2 is aberrantly expressed and associated with an inferior prognosis in patients with acute lymphoblastic leukemia.

Molecular characterization of acute lymphoblastic leukemia (ALL) has greatly improved the ability to categorize and prognostify patients with this disease. In this study, we show that the proto-oncogene CDX2 is aberrantly expressed in the majority of cases with B-lineage ALL and T-ALL. High expression of CDX2 correlated significantly with the ALL subtype pro-B ALL, cALL, Ph(+) ALL and early T-ALL. Furthermore, high expression of CDX2 was associated with inferior overall survival and showed up as a novel and strong risk factor for ALL in bivariate analysis. Functional analyses showed that overexpression of Cdx2 in murine bone marrow progenitors perturbed genes involved in lymphoid development and that depletion of CDX2 in the human ALL cell line Nalm6 inhibited colony formation. These data indicate that aberrant CDX2 expression occurs frequently and has prognostic impact in adult patients with ALL.

[Stem cell therapy. Biology of hematopoietic stem cells]. / Hämatopoetische Stammzelltherapie. Biologische Grundlagen.

In recent years much progress has been made in the understanding of the biology of hematopoietic stem cells (HSC) and their involvement in normal blood cell development. Using immunophenotyping it is possible, to enrich HSC, however, so far we are not able to positively select HSC. For the identification, characterization and quantification of HSC it is necessary to use functional assay systems, such as xenotransplantation models. HSC from bone marrow, peripheral blood and in some cases also cord blood have been used for years in transplantation settings especially in patients with leukemia. A better understanding of the mechanisms underlying stem cell regulation as well as stem cell self renewal would have clinical implications e. g. for clinical transplantation strategies. A number of hematological diseases such as chronic myeloid leukemia originates from a malignant transformed HSC. A better understanding of the biology of normal as well as malignant HSC is therefore crucial not only for a better understanding of the disease, but also for the development of strategies aiming at the discrimination of normal and malignant stem cell candidates and the development of therapies targeting the leukemic stem cell.