Survival of European patients diagnosed with myeloid malignancies: a HAEMACARE study.

Population-based information on the survival of patients with myeloid malignancies is rare mainly because some entities were not recognized as malignant until the publication of the third revision of the International Classification of Diseases for Oncology and World Health Organization classification in 2000. In this study we report the survival of patients with myeloid malignancies, classified by updated criteria, in Europe. We analyzed 58,800 cases incident between 1995 to 2002 in 48 population-based cancer registries from 20 European countries, classified into HAEMACARE myeloid malignancy groupings. The period approach was used to estimate 5-year relative survival in 2000-2002. The relative overall survival rate was 37%, but varied significantly between the major groups: being 17% for acute myeloid leukemia, 20% for myelodysplastic/myeloproliferative neoplasms, 31% for myelodysplastic syndromes and 63% for myeloproliferative neoplasms. Survival of patients with individual disease entities ranged from 90% for those with essential thrombocythemia to 4% for those with acute myeloid leukemia with multilineage dysplasia. Regional European variations in survival were conspicuous for myeloproliferative neoplasms, with survival rates being lowest in Eastern Europe. This is the first paper to present large-scale, European survival data for patients with myeloid malignancies using prognosis-based groupings of entities defined by the third revision of the International Classification of Diseases for Oncology/World Health Organization classifications. Poor survival in some parts of Europe, particularly for treatable diseases such as chronic myeloid leukemia, is of concern for hematologists and public health authorities.

L-Leucine improves the anemia and developmental defects associated with Diamond-Blackfan anemia and del(5q) MDS by activating the mTOR pathway.

Haploinsufficiency of ribosomal proteins (RPs) has been proposed to be the common basis for the anemia observed in Diamond-Blackfan anemia (DBA) and myelodysplastic syndrome with loss of chromosome 5q [del(5q) MDS]. We have modeled DBA and del(5q) MDS in zebrafish using antisense morpholinos to rps19 and rps14, respectively, and have demonstrated that, as in humans, haploinsufficient levels of these proteins lead to a profound anemia. To address the hypothesis that RP loss results in impaired mRNA translation, we treated Rps19 and Rps14-deficient embryos with the amino acid L-leucine, a known activator of mRNA translation. This resulted in a striking improvement of the anemia associated with RP loss. We confirmed our findings in primary human CD34⁺ cells, after shRNA knockdown of RPS19 and RPS14. Furthermore, we showed that loss of Rps19 or Rps14 activates the mTOR pathway, and this is accentuated by L-leucine in both Rps19 and Rps14 morphants. This effect could be abrogated by rapamycin suggesting that mTOR signaling may be responsible for the improvement in anemia associated with L-leucine. Our studies support the rationale for ongoing clinical trials of L-leucine as a therapeutic agent for DBA, and potentially for patients with del(5q) MDS.