Hereditary spherocytosis is a common hemolytic anemia with an estimated incidence of 1 / 2500 births. It is caused by a molecular defect in one or more of the proteins of the red blood cell ...cytoskeleton. Mutations in the ABCB11 gene, encoding the bile salt export pump, can entail progressive familial intrahepatic cholestasis and benign recurred intrahepatic cholestasis. A 18 year old Turkish patient with hereditary spherocytosis was admitted to hospital with pruritus and severe jaundice. Ultrasound examination presented stones in gallbladder and bile duct. After endoscopic retrograde cholangiography with extraction of small bile duct stones abdominal pain resolved and liver enzymes normalized within a few days, but bilirubin and bile acids remained highly elevated. Liver biopsy revealed a severe canalicular cholestasis. Genetic analysis showed the compound heterozygous variants ABCB11 A 444V and 3084A > G. Treatment with ursodesoxycholic acid and intermittent therapy with prednisone reduced pruritus and jaundice with concomitant improvement of blood test. Here we report the first case of a patient with combined hereditary spherocytosis and compound heterozygous ABCB11 gene variants predisposing to intrahepatic cholestasis. Therefore, patients with hemolytic disorders should be investigated for bile acid transporter diseases in case of hyperbilirubinemia and severe cholestasis.
Background In human T cells, telomerase is transiently expressed upon activation and stimulation and, as shown previously, telomerase levels are able to control the lifespan of T cells. To improve ...T-cell expansion it is of critical importance to understand the effects of culture parameters on telomerase activity and lifespan. Methods We investigated the influence of culture condition (FCS, human AB serum and autologous serum) and stimulation (PHA/feeder cells, anti-CD3/CD28 beads) on the lifespan, clonogenicity (number of positive wells), cell cycle, telomerase activity and telomere length of T cells in vitro. Results The proliferative lifespan of T cells expanded with PHA/feeder cells and autologous serum from different donors was doubled compared with stimulation with PHA/feeder cells and AB serum. No or only a small difference was found for T cells expanded with anti-CD3/CD28 beads and autologous or AB serum. The use of autologous serum also increased the clonogenicity to about three-fold compared with the use of AB serum or FCS, without any signs of differences in the fractions of cycling cells. Interestingly, T cells cultured with autologous serum exhibited a significantly higher telomerase activity at day 6 after stimulation and a reduced decline of telomerase activity compared with cultures with AB serum. Discussion The use of autologous serum combined with PHA stimulation and feeder cells remarkably extends the proliferative lifespan and clonogenicity and increases the telomerase activity of human T cells in vitro . This might be useful for applications where large numbers of specific T cells are required.
Bone marrow malignancies are clonal disorders resulting from neoplastic transformation of hematopoietic stem or progenitor cells. Similar to their normal counterparts, transformed blood-forming cells ...remain dependent on signals from the hematopoiesis-regulating stromal environment for survival and proliferation. There is increasing evidence that the microenvironment may also take a more active part in the disease process. A review of the literature on stromal abnormalities in the leukemias, the myelodysplastic syndromes, and multiple myeloma reveals three principal mechanisms by which stromal derangements can contribute to the evolution of a neoplastic disease. In the simplest case, neoplastic blood-forming cells induce reversible changes in stroma function or composition which result in improved growth conditions for the malignant cells ('malignancy-induced microenvironment'). In the second setting, functionally abnormal end cells derived from the malignant clone become an integral part of the stroma system, selectively stimulating the neoplastic cells and inhibiting normal blood cell formation ('malignant microenvironment'). In the third condition, the emergence of a neoplastic cell population is the consequence of a primary stroma lesion characterized by inability to control regular blood cell formation ('malignancy-inducing microenvironment'). The perception of different stroma-related disease mechanisms may eventually lead to the development of alternative therapeutic approaches.
Numerous salvage protocols for relapsed or refractory aggressive non-Hodgkin's lymphomas have been described. The purpose of this retrospective study was to evaluate the efficacy and the toxicity of ...the ASHAP protocol, which combines a continuous infusion of doxorubicin and cisplatin with high-dose cytarabine and methylprednisolone. Twenty-four patients with relapsed or refractory aggressive non-Hodgkin's lymphomas were treated with a median of 3 cycles (range: 1-5) of ASHAP. Twelve patients achieved a complete and four a partial remission for an overall response rate of 67%. The 3-year overall and progression-free survival rates were 60% and 40%, respectively. Ten of the responding patients were consolidated by high-dose chemotherapy. After a median follow-up of 15.5 months, four patients are in continuous complete remission, while six patients suffered relapses (two fatal). For reasons of low risk profile international prognostic index (IPI) score of 0, n=2 or age >60 years ( n=4), consolidation was limited to involved-field radiotherapy in six patients. All of these patients are alive after a median follow-up of 37 months, with two relapses. Factors predicting a poor response to salvage therapy were primary refractory disease, elevated lactate dehydrogenase activity, and an IPI score of >/=2. The principal toxicity was myelosuppression with grade III or IV neutropenia or thrombocytopenia occurring in 88% or 75%, respectively, of the patients. Nonhematological toxicity was generally mild. There were no treatment-related deaths. The ASHAP regimen is a highly active and well-tolerated salvage protocol for patients with relapsed aggressive non-Hodgkin's lymphomas which compares favorably with other established protocols.
Cells of the granulocyte‐macrophage colony stimulating factor (GM‐CSF) or multi‐lineage colony stimulating factor (Multi‐CSF) dependent line FDC‐P1 undergo leukemic transformation after injection ...into irradiated DBA/2 mice. About one third of factor‐independent FDC‐P1 variants isolated from leukemic animals express GM‐CSF or Multi‐CSF, assessed either by bioassay or by sensitive RNA detection using the polymerase chain reaction. All of the GM‐CSF‐secreting lines studied had a rearrangement in one allele of the GM‐CSF gene, three of four Multi‐CSF‐secreting lines had Multi‐CSF gene rearrangements, while factor‐independent lines lacking evidence of growth factor production had no demonstrable CSF gene alterations. All rearrangements were characterized by insertions of novel DNA in the 5′‐flanking regions of the CSF genes. The inserted segments of DNA varied in size between 0.35 and 6.5 kb and displayed restriction enzyme cleavage maps reminiscent of intracisternal A‐particle (IAP) genomes. This was confirmed in two cases by molecular cloning and nucleotide sequence analysis. In these instances, the insertion consisted of solitary IAP long terminal repeats. The transformation system described provides a model for the study of IAP transpositions and their effects on gene activation.
The growth of malignant cells is not only driven by cell-intrinsic factors, but also by the surrounding stroma. Monocytes/Macrophages play an important role in the onset and progression of solid ...cancers. However, little is known about their role in the development of acute myeloid leukemia, a malignant disease characterized by an aberrant development of the myeloid compartment of the hematopoietic system. It is also unclear which factors are responsible for changing the status of macrophage polarization, thus supporting the growth of malignant cells instead of inhibiting it. We report herein that acute myeloid leukemia leads to the invasion of acute myeloid leukemia-associated macrophages into the bone marrow and spleen of leukemic patients and mice. In different leukemic mouse models, these macrophages support the in vitro expansion of acute myeloid leukemia cell lines better than macrophages from non-leukemic mice. The grade of macrophage infiltration correlates in vivo with the survival of the mice. We found that the transcriptional repressor Growth factor independence 1 is crucial in the process of macrophage polarization, since its absence impedes macrophage polarization towards a leukemia supporting state and favors an anti-tumor state both in vitro and in vivo These results not only suggest that acute myeloid leukemia-associated macrophages play an important role in the progression of acute myeloid leukemia, but also implicate Growth factor independence 1 as a pivotal factor in macrophage polarization. These data may provide new insights and opportunities for novel therapies for acute myeloid leukemia.
A number of single nucleotide polymorphisms have been associated with disease predisposition in chronic lymphocytic leukemia. A single nucleotide polymorphism in the MDM2 promotor region, MDM2SNP309, ...was shown to soothe the p53 pathway. In the current study, we aimed to clarify the effect of the MDM2SNP309 on chronic lymphocytic leukemia characteristics and outcome. We performed a meta-analysis of data from 2598 individual patients from 10 different cohorts. Patients' data and genetic analysis for MDM2SNP309 genotype, immunoglobulin heavy chain variable region mutation status and fluorescence in situ hybridization results were collected. There were no differences in overall survival based on the polymorphism (log rank test, stratified by study cohort; P=0.76; GG genotype: cohort-adjusted median overall survival of 151 months; TG: 153 months; TT: 149 months). In a multivariable Cox proportional hazards regression analysis, advanced age, male sex and unmutated immunoglobulin heavy chain variable region genes were associated with inferior survival, but not the MDM2 genotype. The MDM2SNP309 is unlikely to influence disease characteristics and prognosis in chronic lymphocytic leukemia. Studies investigating the impact of individual single nucleotide polymorphisms on prognosis are often controversial. This may be due to selection bias and small sample size. A meta-analysis based on individual patient data provides a reasonable strategy for prognostic factor analyses in the case of small individual studies. Individual patient data-based meta-analysis can, therefore, be a powerful tool to assess genetic risk factors in the absence of large studies.
PDF
