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Dive into the research topics where Jan Samuelsson is active.

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Featured researches published by Jan Samuelsson.


British Journal of Haematology | 2003

A validated decision model for treating the anaemia of myelodysplastic syndromes with erythropoietin + granulocyte colony-stimulating factor: significant effects on quality of life

Eva Hellström-Lindberg; Nina Gulbrandsen; Greger Lindberg; Tomas Ahlgren; Inger Marie S. Dahl; Ingunn Dybedal; Gunnar Grimfors; Eva Hesse‐Sundin; Martin Hjorth; Lena Kanter-Lewensohn; Olle Linder; Michaela Luthman; Eva Löfvenberg; Gunnar Öberg; Anja Porwit‐MacDonald; Anders Rådlund; Jan Samuelsson; Jon Magnus Tangen; Ingemar Winquist; Finn Wisløff

Summary. We have published previously a prototype of a decision model for anaemic patients with myelodysplastic syndromes (MDS), in which transfusion need and serum erythropoietin (S‐Epo) were used to define three groups with different probabilities of erythroid response to treatment with granulocyte colony‐stimulating factor (G‐CSF) + Epo. S‐Epo ≤ 500 U/l and a transfusion need of < 2 units/month predicted a high probability of response to treatment, S‐Epo > 500 U/l and ≥ 2 units/month for a poor response, whereas the presence of only one negative prognostic marker predicted an intermediate response. A total of 53 patients from a prospective study were included in our evaluation sample. Patients with good or intermediate probability of response were treated with G‐CSF + Epo. The overall response rate was 42% with 28·3% achieving a complete and 13·2% a partial response to treatment. The response rates were 61% and 14% in the good and intermediate predictive groups respectively. The model retained a significant predictive value in the evaluation sample (P < 0·001). Median duration of response was 23 months. Scores for global health and quality of life (QOL) were significantly lower in MDS patients than in a reference population, and fatigue and dyspnoea was significantly more prominent. Global QOL improved in patients responding to treatment (P = 0·01). The validated decision model defined a subgroup of patients with a response rate of 61% (95% confidence interval 48–74%) to treatment with G‐CSF + Epo. The majority of these patients have shown complete and durable responses.


Proceedings of the National Academy of Sciences of the United States of America | 2007

Lenalidomide inhibits the malignant clone and up-regulates the SPARC gene mapping to the commonly deleted region in 5q− syndrome patients

Andrea Pellagatti; Martin Jädersten; Ann-Mari Forsblom; Helen Cattan; Birger Christensson; Emma Emanuelsson; Mats Merup; Lars J Nilsson; Jan Samuelsson; Birgitta Sander; James S. Wainscoat; Jacqueline Boultwood; Eva Hellström-Lindberg

Myelodysplastic syndromes (MDSs) are a group of hematopoietic stem cell disorders characterized by ineffective hematopoiesis and peripheral blood cytopenias. Lenalidomide has dramatic therapeutic effects in patients with low-risk MDS and a chromosome 5q31 deletion, resulting in complete cytogenetic remission in >60% of patients. The molecular basis of this remarkable drug response is unknown. To gain insight into the molecular targets of lenalidomide we investigated its in vitro effects on growth, maturation, and global gene expression in isolated erythroblast cultures from MDS patients with del(5)(q31). Lenalidomide inhibited growth of differentiating del(5q) erythroblasts but did not affect cytogenetically normal cells. Moreover, lenalidomide significantly influenced the pattern of gene expression in del(5q) intermediate erythroblasts, with the VSIG4, PPIC, TPBG, activin A, and SPARC genes up-regulated by >2-fold in all samples and many genes involved in erythropoiesis, including HBA2, GYPA, and KLF1, down-regulated in most samples. Activin A, one of the most significant differentially expressed genes between lenalidomide-treated cells from MDS patients and healthy controls, has pleiotropic functions, including apoptosis of hematopoietic cells. Up-regulation and increased protein expression of the tumor suppressor gene SPARC is of particular interest because it is antiproliferative, antiadhesive, and antiangiogenic and is located at 5q31-q32, within the commonly deleted region in MDS 5q− syndrome. We conclude that lenalidomide inhibits growth of del(5q) erythroid progenitors and that the up-regulation of SPARC and activin A may underlie the potent effects of lenalidomide in MDS with del(5)(q31). SPARC may play a role in the pathogenesis of the 5q− syndrome.


Journal of Clinical Oncology | 2012

Myeloproliferative Neoplasm (MPN) Symptom Assessment Form Total Symptom Score: Prospective International Assessment of an Abbreviated Symptom Burden Scoring System Among Patients With MPNs

Robyn M. Emanuel; Amylou C. Dueck; Holly Geyer; Jean-Jacques Kiladjian; Stefanie Slot; Sonja Zweegman; Peter te Boekhorst; Suzan Commandeur; Harry C. Schouten; Federico Sackmann; Ana Kerguelen Fuentes; Dolores Hernandez-Maraver; Heike L. Pahl; Martin Griesshammer; Frank Stegelmann; Konstanze Doehner; Thomas Lehmann; Karin Bonatz; Andreas Reiter; Francoise Boyer; Gabriel Etienne; Jean Christophe Ianotto; Dana Ranta; Lydia Roy; Jean Yves Cahn; Claire N. Harrison; Deepti Radia; Pablo J. Muxi; Norman Maldonado; Carlos Besses

PURPOSE Myeloproliferative neoplasm (MPN) symptoms are troublesome to patients, and alleviation of this burden represents a paramount treatment objective in the development of MPN-directed therapies. We aimed to assess the utility of an abbreviated symptom score for the most pertinent and representative MPN symptoms for subsequent serial use in assessing response to therapy. PATIENTS AND METHODS The Myeloproliferative Neoplasm Symptom Assessment Form total symptom score (MPN-SAF TSS) was calculated as the mean score for 10 items from two previously validated scoring systems. Questions focus on fatigue, concentration, early satiety, inactivity, night sweats, itching, bone pain, abdominal discomfort, weight loss, and fevers. RESULTS MPN-SAF TSS was calculable for 1,408 of 1,433 patients with MPNs who had a mean score of 21.2 (standard deviation [SD], 16.3). MPN-SAF TSS results significantly differed among MPN disease subtypes (P<.001), with a mean of 18.7 (SD, 15.3), 21.8 (SD, 16.3), and 25.3 (SD, 17.2) for patients with essential thrombocythemia, polycythemia vera, and myelofibrosis, respectively. The MPN-SAF TSS strongly correlated with overall quality of life (QOL; r=0.59; P<.001) and European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30 (EORTC QLQ-C30) functional scales (all P<.001 and absolute r≥0.50 except social functioning r=0.48). No significant trends were present when comparing therapy subgroups. The MPN-SAF TSS had excellent internal consistency (Cronbachs α=.83). Factor analysis identified a single underlying construct, indicating that the MPN-SAF TSS is an appropriate, unified scoring method. CONCLUSION The MPN-SAF TSS is a concise, valid, and accurate assessment of MPN symptom burden with demonstrated clinical utility in the largest prospective MPN symptom study to date. This new prospective scoring method may be used to assess MPN symptom burden in both clinical practice and trial settings.


Journal of Clinical Oncology | 2011

Treatment-Related Risk Factors for Transformation to Acute Myeloid Leukemia and Myelodysplastic Syndromes in Myeloproliferative Neoplasms

Magnus Björkholm; Åsa Rangert Derolf; Malin Hultcrantz; Sigurdur Y. Kristinsson; Charlotta Ekstrand; Lynn R. Goldin; Bjorn Andreasson; Gunnar Birgegård; Olle Linder; Claes Malm; Berit Markevärn; Lars J Nilsson; Jan Samuelsson; Fredrik Granath; Ola Landgren

PURPOSE Patients with myeloproliferative neoplasms (MPNs), including polycythemia vera, essential thrombocythemia, and primary myelofibrosis, have a propensity to develop acute myeloid leukemia (AML) and myelodysplastic syndromes (MDSs). Using population-based data from Sweden, we assessed the role of MPN treatment and subsequent AML/MDS risk with special focus on the leukemogenic potential of hydroxyurea (HU). METHODS On the basis of a nationwide MPN cohort (N = 11,039), we conducted a nested case-control study, including 162 patients (153 and nine with subsequent AML and MDS diagnosis, respectively) and 242 matched controls. We obtained clinical and MPN treatment data for all patients. Using logistic regression, we calculated odds ratios (ORs) as measures of AML/MDS risk. RESULTS Forty-one (25%) of 162 patients with MPNs with AML/MDS development were never exposed to alkylating agents, radioactive phosphorous (P(32)), or HU. Compared with patients with who were not exposed to HU, the ORs for 1 to 499 g, 500 to 999 g, more than 1,000 g of HU were 1.5 (95% CI, 0.6 to 2.4), 1.4 (95% CI, 0.6 to 3.4), and 1.3 (95% CI, 0.5 to 3.3), respectively, for AML/MDS development (not significant). Patients with MPNs who received P(32) greater than 1,000 MBq and alkylators greater than 1 g had a 4.6-fold (95% CI, 2.1 to 9.8; P = .002) and 3.4-fold (95% CI, 1.1 to 10.6; P = .015) increased risk of AML/MDS, respectively. Patients receiving two or more cytoreductive treatments had a 2.9-fold (95% CI, 1.4 to 5.9) increased risk of transformation. CONCLUSION The risk of AML/MDS development after MPN diagnosis was significantly associated with high exposures of P(32) and alkylators but not with HU treatment. Twenty-five percent of patients with MPNs who developed AML/MDS were not exposed to cytotoxic therapy, supporting a major role for nontreatment-related factors.


Blood | 2013

Revised response criteria for polycythemia vera and essential thrombocythemia: an ELN and IWG-MRT consensus project

Giovanni Barosi; Ruben A. Mesa; Guido Finazzi; Claire N. Harrison; Jean-Jacques Kiladjian; Eva Lengfelder; Mary Frances McMullin; Francesco Passamonti; Alessandro M. Vannucchi; Carlos Besses; Heinz Gisslinger; Jan Samuelsson; Srdan Verstovsek; Ronald Hoffman; Animesh Pardanani; Francisco Cervantes; Ayalew Tefferi; Tiziano Barbui

Standardized response criteria to interpret and compare clinical trials are needed for approval of new therapeutic agents by regulatory agencies. The European LeukemiaNet (ELN) response criteria for essential thrombocythemia (ET) and polycythemia vera (PV) issued in 2009 have been widely adopted as end points in a number of recent clinical trials. However, evidence exists that they do not predict response or provide clinically relevant measures of benefit for the patients. This article presents revised recommendations for assessing response in ET and PV provided by a working group established by ELN and International Working Group-Myeloproliferative Neoplasms Research and Treatment. New definitions of complete and partial remission incorporate clinical, hematological, and histological response assessments that include a standardized symptom assessment form and consider absence of disease progression and vascular events. We anticipate that these criteria will be adopted widely to facilitate the development of new and more effective therapies for ET and PV.


Cancer | 2006

A phase II trial of pegylated interferon alpha-2b therapy for polycythemia vera and essential thrombocythemia: feasibility, clinical and biologic effects, and impact on quality of life.

Jan Samuelsson; Hans Carl Hasselbalch; Øystein Bruserud; Snezana Temerinac; Yvonne Brandberg; Mats Merup; Olle Linder; Magnus Björkholm; Heike L. Pahl; Gunnar Birgegård

Conventional interferon‐α (IFN) is an effective treatment for patients with myeloproliferative disorders. However, many patients discontinue therapy because of side effects.


European Journal of Cancer | 2010

Redefining the role of interferon in the treatment of malignant diseases

Sergio Bracarda; Alexander M.M. Eggermont; Jan Samuelsson

Interferon (IFN) is a cytokine with a long history of use as immunotherapy in the treatment of various solid tumours and haematological malignancies. The initial use of IFN in cancer therapy was based on its antiproliferative and immunomodulatory effects, and it has been shown more recently to have cytotoxic and anti-angiogenic properties. These features make it a rational anticancer therapy; however, advances in our understanding of the molecular mechanisms involved in cancer development and growth and the availability of effective, alternative therapies have led to IFN therapy being superseded in many cancers. IFN is still commonly used in renal cell carcinoma (RCC), melanoma and myeloproliferative disorders, in which its optimal dose and treatment duration remain to be established despite extensive clinical experience. Preclinical studies of the mechanism of action of IFN suggest that different antitumour effects are relevant at different doses, providing a rationale to explore the use of different dose regimens of IFN, particularly when combined with other therapies. In particular, the advent of novel anti-angiogenic therapies in RCC means that the role of IFN needs to be re-examined with a focus on how best to maximise efficacy and minimise toxicity when used with these agents. This review will focus on the therapeutic use of IFN in these disorders, provide an overview of available data and consider what the data suggest regarding the potential optimal use of IFN in the future.


Haematologica | 2010

Autoimmunity and the risk of myeloproliferative neoplasms

Sigurdur Y. Kristinsson; Ola Landgren; Jan Samuelsson; Magnus Björkholm; Lynn R. Goldin

The causes of myeloproliferative neoplasm (MPN) are unknown. We conducted a large population-based study including 11,039 myeloproliferative neoplasm patients and 43,550 matched controls with the aim of assessing the associations between a personal history of a broad span of autoimmune diseases and subsequent risk of myeloproliferative neoplasm. We found a prior history of any autoimmune disease to be associated with a significantly increased risk of myeloproliferative neoplasms (odds ratio (OR)=1.2; 95% confidence interval (CI) 1.0–1.3; P=0.021). Specifically, we found an increased risk of MPNs associated with a prior immune thrombocytopenic purpura (2.9; 1.7–7.2), Crohn’s disease (1.8; 1.1–3.0), polymyalgia rheumatica (1.7; 1.2–2.5), giant cell arteritis (5.9; 2.4–14.4), Reiter’s syndrome (15.9; 1.8–142) and aplastic anemia (7.8; 3.7–16.7). The risk of myeloproliferative neoplasms associated with prior autoimmune diseases is modest but statistically significant. Future studies are needed to unravel the effects of these autoimmune diseases themselves, their treatment, or common genetic susceptibility.


European Journal of Haematology | 2009

Treatment of myelodysplastic syndromes with retinoic acid and 1α-hydroxy-vitamin D3 in combination with low-dose ara-C is not superior to ara-C alone. Results from a randomized study

Eva Hellström; Karl-Henrik Robèrt; Jan Samuelsson; Christina Lindemalm; Gunnar Grimfors; Eva Kimby; Gunnar Öberg; Ingemar Winqvist; Rolf Billström; Jan Carneskog; Magnus Dahlén; Mette Stockner; Finn Wisløff; Ingunn Dybedal; Inger-Marie Dahl; Åke Öst

Abstract: 63 evaluable patients with myelodysplastic syndromes (MDS) and 15 with acute myelogenous leukemia (AML) were randomized between low‐dose ara‐C (arm A) and low dose ara‐C in combination with 13‐cis‐retinoic acid (13‐CRA) and 1α‐hydroxy‐vitamin D3 (1α D3) (arm B). 69 patients were evaluable and 18 (26.1%) responded to therapy. The addition of 13‐CRA and 1α D3 had no positive influence on survival of the patients, remission rates or duration of remissions. 12/27 patients in arm A and 6/29 patients in arm B progressed from MDS to AML during the course of the study (p = 0.0527). Arm B gave significantly more side‐effects than arm A (p = 0.005). Therapeutic effects of 13‐CRA and 1α D3 on MDS is not supported by this study. However, an inhibiting effect on AML development in some MDS subgroups cannot be excluded.


European Journal of Haematology | 2009

Therapeutic effects of low‐dose cytosine arabinoside, alpha‐interferon, 1α‐hydroxyvitamin D3 and retinoic acid in acute leukemia and myelodysplastic syndromes

Eva Hellström; Karl-Henrik Robèrt; Gösta Gahrton; Håkan Mellstedt; Christina Lindemalm; Stefan Einhorn; Magnus Björkholm; Gunnar Grimfors; A‐M. Udén; Jan Samuelsson; Åke Öst; Andreas Killander; Bo Nilsson; Ingemar Winqvist; Inge Olsson

62 evaluable patients with myelodysplastic syndromes (MDS) or acute leukemia were treated with different combinations of low dose ara‐C, α‐interferon (IFN), 1α‐hydroxyvitamin D3 (vit D3) and retinoic acid. The aim was to study the efficacy and toxicity of each combination. The overall rate was 44%. Of these, 50% responded favorably to the combination of IFN, vit D3 and retinoic acid (IDR), which was comparable to the response rate of 43% for low‐dose ara‐C. The results of the IDR treatment may be explained by additive or synergistic effects between the separate drugs in the combination. Ara‐C and IDR treatment was generally well‐tolerated but interferon gave more side effects than any other drug used in the study. Evaluation of the full combination of ara‐C, IFN, vit D3 and retinoic acid was not possible because of toxicity. Marrow hypoplasia was infrequent (5/27 patients) in cases responding favorably to treatment. Complete remissions were not longer than partial remissions or significant responses.

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Claire N. Harrison

Guy's and St Thomas' NHS Foundation Trust

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Bjorn Andreasson

Sahlgrenska University Hospital

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Sonja Zweegman

VU University Medical Center

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Carlos Besses

Autonomous University of Barcelona

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Magnus Björkholm

Karolinska University Hospital

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