44 research outputs found
Dasatinib induces fast and deep responses in newly diagnosed chronic myeloid leukaemia patients in chronic phase : clinical results from a randomised phase-2 study (NordCML006)
Peer reviewe
Molecular status 36 months after TKI discontinuation in CML is highly predictive for subsequent loss of MMR-final report from AFTER-SKI
Non peer reviewe
Tyrosine kinase inhibitor therapy-induced changes in humoral immunity in patients with chronic myeloid leukemia
Purpose Tyrosine kinase inhibitors (TKIs) have well-characterized immunomodulatory effects on T and NK cells, but the effects on the humoral immunity are less well known. In this project, we studied TKI-induced changes in B cell-mediated immunity. Methods We collected peripheral blood (PB) and bone marrow (BM) samples from chronic myeloid leukemia (CML) patients before and during first-line imatinib (n = 20), dasatinib (n = 16), nilotinib (n = 8), and bosutinib (n = 12) treatment. Plasma immunoglobulin levels were measured, and different B cell populations in PB and BM were analyzed with flow cytometry. Results Imatinib treatment decreased plasma IgA and IgG levels, while dasatinib reduced IgM levels. At diagnosis, the proportion of patients with IgA, IgG, and IgM levels below the lower limit of normal (LLN) was 0, 11, and 6% of all CML patients, respectively, whereas at 12 months timepoint the proportions were 6% (p = 0.13), 31% (p = 0.042) and 28% (p = 0.0078). Lower initial Ig levels predisposed to the development of hypogammaglobulinemia during TKI therapy. Decreased Ig levels in imatinibtreated patients were associated with higher percentages of immature BM B cells. The patients, who had low Ig levels during the TKI therapy, had significantly more frequent minor infections during the follow-up compared with the patients with normal Ig values (33% vs. 3%, p = 0.0016). No severe infections were reported, except recurrent upper respiratory tract infections in one imatinib-treated patient, who developed severe hypogammaglobulinemia. Conclusions TKI treatment decreases plasma Ig levels, which should be measured in patients with recurrent infections.Peer reviewe
Optimization and evaluation of electroporation delivery of siRNA in the human leukemic CEM cell line
In order to study nucleoside analog activation in the CEM cell line, a transfection protocol had to be optimized in order to silence an enzyme involved in nucleoside analog activation. Hematopoetic cell lines can be difficult to transfect with traditional lipid-based transfection, so the electroporation technique was used. Field strength, pulse length, temperature, electroporation media, siRNA concentration, among other conditions were tested in order to obtain approximately 70-80% mRNA and enzyme activity downregulation of the cytosolic enzyme deoxycytidine kinase (dCK), necessary for nucleoside analog activation. Downregulation was assessed at mRNA and enzyme activity levels. After optimizing the protocol, a microarray analysis was performed in order to investigate whether the downregulation was specific. Additionally two genes were differentially expressed besides the downregulation of dCK. These were however of unknown function. The leakage of intracellular nucleotides was also addressed in the electroporated cells since it can affect the DNA repair mechansism and the efficiency of nucleoside analogs. Three of these pools were increased compared to untreated, unelectroporated cells. The siRNA transfected cells with reduced dCK expression and activity showed reduced sensitivity to several nucleoside analogs as expected. The multidrug resistance to other drugs, as seen in nucleoside analog-induced resistant cells, was not seen with this model.The original publication is available at www.springerlink.com:Anna Fyrberg and Kourosh Lotfi, Optimization and evaluation of electroporation delivery of siRNA in the human leukemic CEM cell line, 2010, CYTOTECHNOLOGY, (62), 6, 497-507.http://dx.doi.org/10.1007/s10616-010-9309-6Copyright: Springer Science Business Mediahttp://www.springerlink.com
Linköping University Post Print
Optimization and evaluation of electroporation delivery of siRNA in the human leukemic CEM cell lin
Soluble sugars and proline accumulation play a role as effective indices for drought tolerance screening in Persian walnut (
Introduction. Drought stress is the major factor affecting growth,
development and production of walnut trees. In Iran, approximately 33Â Mha of land is
affected by salinization and drought stress. Finding genetic resources tolerant to drought
stress at different growth stages is important for such semi-arid regions. Our aim was to
understand better the adaptive mechanisms that enable different genotypes of walnut
population to survive under drought stress, and to provide some useful clues for walnut
tree breeding toward improved drought tolerance with utilization of existing
drought-tolerant genetic resources. Materials and methods. To study the
mechanism(s) involved in drought tolerance of some Persian walnut genotypes, drought
stress was induced using polyethylene glycol-6000 to produce water potentials of 0Â Mpa
(control), –0.10 MPa, –0.50 MPa, –0.75 MPa, –1.00 MPa, –1.50 MPa and –2.00 MPa. The amount
of proline and soluble sugar accumulation in four walnut genotypes
(‘Panegine20’, ‘Lara’, ‘Serr’ and ‘Chandler’) were determined after being
exposed to the various water potential levels. Results. The rates of seed
germination in all genotypes were significantly reduced by low external water potentials.
Plants exposed to water stress had a higher amount of soluble sugars in roots and shoots
of tolerant genotypes (‘Panegine20’ and ‘Chandler’) and a lower amount of
starch in their tissues. These results imply the important roles of soluble sugars as
solutes conferring resistance to drought in these genotypes. The free proline levels were
also increased in response to drought stress. They were higher in drought-tolerant
genotypes than in sensitive ones (‘Lara’ and ‘Serr’). Proline increased more in shoots
than in roots. However, the soluble sugar and starch fluctuations were higher in the
roots. Conclusion. Our results support a direct correlation between the
degree of drought stress and proline content. As a consequence, proline concentrations
could be used as a biochemical marker of drought stress level in walnut plants