55 research outputs found
Poetry as Compass: Chaos, Complexity, and the Creative Voice
In the following article, I will relate poetry as a genre to complex systems and explain why this approach lends itself particularly well to a study about creativity. This will require us to alter our view and to move from a mechanistic model for explaining the emergence of life, to a systemic model. In other words, instead of reducing a phenomenon to a single object or concept in order to understand it, we will attempt to see it within its larger context by focusing on the lateral connections between its various parts
Inhibition of IGF1-R overcomes IGFBP7-induced chemotherapy resistance in T-ALL
Background T-cell acute lymphoblastic leukemia (T-ALL) is a genetically
heterogeneous disease with the need for treatment optimization. Previously,
high expression of Insulin-like growth factor binding protein 7 (IGFBP7), a
member of the IGF system, was identified as negative prognostic factor in
adult T-ALL patients. Since aberrant IGFBP7 expression was observed in a
variety of neoplasia and was relevant for prognosis in T-ALL, we investigated
the functional role of IGFBP7 in Jurkat and Molt-4 cells as in vitro models
for T-ALL. Methods Jurkat and Molt-4 cells were stably transfected with an
IGFBP7 over-expression vector or the empty vector as control. Proliferation of
the cells was assessed by WST-1 assays and cell cycle status was measured by
flow-cytometry after BrDU/7-AAD staining. The effect of IGFBP7 over-expression
on sensitivity to cytostatic drugs was determined in AnnexinV/7-AAD assays.
IGF1-R protein expression was measured by Western Blot and flow-cytometric
analysis. IGF1-R associated gene expression profiles were generated from
microarray gene expression data of 86 T-ALL patients from the Microarrays
Innovations in Leukemia (MILE) multicenter study. Results IGFBP7-transfected
Jurkat cells proliferated less, leading to a longer survival in a
nutrient–limited environment. Both IGFBP7-transfected Jurkat and Molt-4 cells
showed an arrest in the G0/G1 cell cycle phase. Furthermore, Jurkat
IGFBP7-transfected cells were resistant to vincristine and asparaginase
treatment. Surface expression and whole protein measurement of IGF1-R protein
expression showed a reduced abundance of the receptor after IGFBP7
transfection in Jurkat cells. Interestingly, combination of the IGF1-R
inhibitor NPV-AEW541 restored sensitivity to vincristine in IGFBP7-transfected
cells. Additionally, IGF1-R associated GEP revealed an up-regulation of
important drivers of T-ALL pathogenesis and regulators of chemo-resistance and
apoptosis such as NOTCH1, BCL-2, PRKCI, and TP53. Conclusion This study
revealed a proliferation inhibiting effect of IGFBP7 by G0/G1 arrest and a
drug resistance-inducing effect of IGFBP7 against vincristine and asparaginase
in T-ALL. These results provide a model for the previously observed
association between high IGFBP7 expression and chemotherapy failure in T-ALL
patients. Since the resistance against vincristine was abolished by IGF1-R
inhibition, IGFBP7 could serve as biomarker for patients who may benefit from
therapies including IGF1-R inhibitors in combination with chemotherapy
Macrocyclic tetramers—structural investigation of peptide-peptoid hybrids
Outstanding affinity and specificity are the main characteristics of peptides, rendering them interesting compounds for basic and medicinal research. However, their biological applicability is limited due to fast proteolytic degradation. The use of mimetic peptoids overcomes this disadvantage, though they lack stereochemical information at the α-carbon. Hybrids composed of amino acids and peptoid monomers combine the unique properties of both parent classes. Rigidification of the backbone increases the affinity towards various targets. However, only little is known about the spatial structure of such constrained hybrids. The determination of the three-dimensional structure is a key step for the identification of new targets as well as the rational design of bioactive compounds. Herein, we report the synthesis and the structural elucidation of novel tetrameric macrocycles. Measurements were taken in solid and solution states with the help of X-ray scattering and NMR spectroscopy. The investigations made will help to find diverse applications for this new, promising compound class
Macrocyclic Tetramers—Structural Investigation of Peptide-Peptoid Hybrids
Outstanding affinity and specificity are the main characteristics of peptides, rendering them interesting compounds for basic and medicinal research. However, their biological applicability is limited due to fast proteolytic degradation. The use of mimetic peptoids overcomes this disadvantage, though they lack stereochemical information at the α-carbon. Hybrids composed of amino acids and peptoid monomers combine the unique properties of both parent classes. Rigidification of the backbone increases the affinity towards various targets. However, only little is known about the spatial structure of such constrained hybrids. The determination of the three-dimensional structure is a key step for the identification of new targets as well as the rational design of bioactive compounds. Herein, we report the synthesis and the structural elucidation of novel tetrameric macrocycles. Measurements were taken in solid and solution states with the help of X-ray scattering and NMR spectroscopy. The investigations made will help to find diverse applications for this new, promising compound class
New directions in sacred journeys research
Also available at: https://arrow.tudublin.ie/cgi/viewcontent.cgi?article=1383&context=ijrtpIn July 2019, the Sacred Journeys 6th global conference was convened at historic Maynooth University in Ireland. The conference attracted over 30 international pilgrimage scholars from 14 countries. The range of research topics presented over the two- day gathering was impressive and the papers presented in this issue of the International Journal of Religious Tourism and Pilgrimage represent a sampling of the new directions that scholars are taking in their examination of the art and practice of pilgrimage.peer-reviewe
FLT3 mutations in Early T-Cell Precursor ALL characterize a stem cell like leukemia and imply the clinical use of tyrosine kinase inhibitors
Early T-cell precursor acute lymphoblastic leukemia (ETP-ALL) has been identified as high-risk subgroup of acute T-lymphoblastic leukemia (T-ALL) with a high rate of FLT3-mutations in adults. To unravel the underlying pathomechanisms and the clinical course we assessed molecular alterations and clinical characteristics in a large cohort of ETP-ALL (n = 68) in comparison to non-ETP T-ALL adult patients. Interestingly, we found a high rate of FLT3-mutations in ETP-ALL samples (n = 24, 35%). Furthermore, FLT3 mutated ETP-ALL was characterized by a specific immunophenotype (CD2+/CD5-/CD13+/CD33-), a distinct gene expression pattern (aberrant expression of IGFBP7, WT1, GATA3) and mutational status (absence of NOTCH1 mutations and a low frequency, 21%, of clonal TCR rearrangements). The observed low GATA3 expression and high WT1 expression in combination with lack of NOTCH1 mutations and a low rate of TCR rearrangements point to a leukemic transformation at the pluripotent prothymocyte stage in FLT3 mutated ETP-ALL. The clinical outcome in ETP-ALL patients was poor, but encouraging in those patients with allogeneic stem cell transplantation (3-year OS: 74%). To further explore the efficacy of targeted therapies, we demonstrate that T-ALL cell lines transfected with FLT3 expression constructs were particularly sensitive to tyrosine kinase inhibitors. In conclusion, FLT3 mutated ETP-ALL defines a molecular distinct stem cell like leukemic subtype. These data warrant clinical studies with the implementation of FLT3 inhibitors in addition to early allogeneic stem cell transplantation for this high risk subgroup
An alternative CYB5A transcript is expressed in aneuploid ALL and enriched in relapse
Background: B-cell precursor acute lymphoblastic leukemia (BCP-ALL) is a genetically heterogenous malignancy with poor prognosis in relapsed adult patients. The genetic basis for relapse in aneuploid subtypes such as near haploid (NH) and high hyperdiploid (HeH) BCP-ALL is only poorly understood. Pathogenic genetic alterations remain to be identified. To this end, we investigated the dynamics of genetic alterations in a matched initial diagnosis-relapse (ID-REL) BCP-ALL cohort. Here, we firstly report the identification of the novel genetic alteration CYB5Aalt, an alternative transcript of CYB5A, in two independent cohorts.
Methods: We identified CYB5alt in the RNAseq-analysis of a matched ID-REL BCP-ALL cohort with 50 patients and quantified its expression in various molecular BCP-ALL subtypes. Findings were validated in an independent cohort of 140 first diagnosis samples from adult BCP-ALL patients. Derived from patient material, the alternative open reading frame of CYB5Aalt was cloned (pCYB5Aalt) and pCYB5Aalt or the empty vector were stably overexpressed in NALM-6 cells. RNA sequencing was performed of pCYB5Aalt clones and empty vector controls followed by differential expression analysis, gene set enrichment analysis and complementing cell death and viability assays to determine functional implications of CYB5Aalt.
Results: RNAseq data analysis revealed non-canonical exon usage of CYB5Aalt starting from a previously undescribed transcription start site. CYB5Aalt expression was increased in relapsed BCP-ALL and its occurrence was specific towards the shared gene expression cluster of NH and HeH BCP-ALL in independent cohorts. Overexpression of pCYB5Aalt in NALM-6 cells induced a distinct transcriptional program compared to empty vector controls with downregulation of pathways related to reported functions of CYB5A wildtype. Interestingly, CYB5A wildtype expression was decreased in CYB5Aalt samples in silico and in vitro. Additionally, pCYB5Aalt NALM-6 elicited a more resistant drug response.
Conclusions: Across all age groups, CYB5Aalt was the most frequent secondary genetic event in relapsed NH and HeH BCP-ALL. In addition to its high subgroup specificity, CYB5Aalt is a novel candidate to be potentially implicated in therapy resistance in NH and HeH BCP-ALL. This is underlined by overexpressing CYB5Aalt providing first evidence for a functional role in BCL2-mediated apoptosis
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