Classification and clinical behavior of blastic plasmacytoid dendritic cell neoplasms according to their maturation-associated immunophenotypic profile

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare subtype of leukemia/lymphoma, whose diagnosis can be difficult to achieve due to its clinical and biological heterogeneity, as well as its overlapping features with other hematologic malignancies. In this study we investigated whether the association between the maturational stage of tumor cells and the clinico-biological and prognostic features of the disease, based on the analysis of 46 BPDCN cases classified into three maturation-associated subgroups on immunophenotypic grounds. Our results show that blasts from cases with an immature plasmacytoid dendritic cell (pDC) phenotype exhibit an uncommon CD56- phenotype, coexisting with CD34+ non-pDC tumor cells, typically in the absence of extramedullary (e.g. skin) disease at presentation. Conversely, patients with a more mature blast cell phenotype more frequently displayed skin/extramedullary involvement and spread into secondary lymphoid tissues. Despite the dismal outcome, acute lymphoblastic leukemia-type therapy (with central nervous system prophylaxis) and/or allogeneic stem cell transplantation appeared to be the only effective therapies. Overall, our findings indicate that the maturational profile of pDC blasts in BPDCN is highly heterogeneous and translates into a wide clinical spectrum -from acute leukemia to mature lymphoma-like behavior-, which may also lead to variable diagnosis and treatment.

TRIB2 in human AML: a biological and clinical investigation

Acute myeloid leukemia (AML) involves the proliferation, abnormal survival and arrest of cells at a very early stage of myeloid cell differentiation. The biological and clinical heterogeneity of this disease complicates treatment and highlights the significance of understanding the underlying causes of AML, which may constitute potential therapeutic targets, as well as offer prognostic information. Tribbles homolog 2 (Trib2) is a potent murine oncogene capable of inducing transplantable AML with complete penetrance. The pathogenicity of Trib2 is attributed to its ability to induce proteasomal degradation of the full length isoform of the transcription factor CCAAT/enhancer-binding protein alpha (C/EBPα p42). The role of TRIB2 in human AML cells, however, has not been systematically investigated or targeted. Across human cancers, TRIB2 oncogenic activity was found to be associated with its elevated expression. In the context of AML, TRIB2 overexpression was suggested to be associated with the large and heterogeneous subset of cytogenetically normal AML patients. Based upon the observation that overexpression of TRIB2 has a role in cellular transformation, the effect of modulating its expression in human AML was examined in a human AML cell line that expresses high levels of TRIB2, U937 cells. Specific suppression of TRIB2 led to impaired cell growth, as a consequence of both an increase in apoptosis and a decrease in cell proliferation. Consistent with these in vitro results, TRIB2 silencing strongly reduced progression of the U937 in vivo xenografts, accompanied by detection of a lower spleen weight when compared with mice transplanted with TRIB2- expressing control cells. Gene expression analysis suggested that TRIB2 modulates apoptosis and cell-cycle sensitivity by influencing the expression of a subset of genes known to have implications on these phenotypes. Furthermore, TRIB2 was found to be expressed in a significant subset of AML patient samples analysed. To investigate whether increased expression of this gene could be afforded prognostic significance, primary AML cells with dichotomized levels of TRIB2 transcripts were evaluated in terms of their xenoengraftment potential, an assay reported to correlate with disease aggressiveness observed in humans. A small cohort of analysed samples with higher TRIB2 expression did not associate with preferential leukaemic cell engraftment in highly immune-deficient mice, hence, not predicting for an adverse prognosis. However, further experiments including a larger cohort of well characterized AML patients would be needed to clarify TRIB2 significance in the diagnostic setting. Collectively, these data support a functional role for TRIB2 in the maintenance of the oncogenic properties of human AML cells and suggest TRIB2 can be considered a rational therapeutic target. Proteasome inhibition has emerged as an attractive target for the development of novel anti-cancer therapies and results from translational research and clinical trials support the idea that proteasome inhibitors should be considered in the treatment of AML. The present study argued that proteasome inhibition would effectively inhibit the function of TRIB2 by abrogating C/EBPα p42 protein degradation and that it would be an effective pharmacological targeting strategy in TRIB2-positive AMLs. Here, a number of cell models expressing high levels of TRIB2 were successfully targeted by treatment with proteasome inhibitors, as demonstrated by multiple measurements that included increased cytotoxicity, inhibition of clonogenic growth and anti-AML activity in vivo. Mechanistically, it was shown that block of the TRIB2 degradative function led to an increase of C/EBPα p42 and that response was specific to the TRIB2-C/EBPα axis. Specificity was addressed by a panel of experiments showing that U937 cells (express detectable levels of endogenous TRIB2 and C/EBPα) treated with the proteasome inhibitor bortezomib (Brtz) displayed a higher cytotoxic response upon TRIB2 overexpression and that ectopic expression of C/EBPα rescued cell death. Additionally, in C/EBPα-negative leukaemia cells, K562 and Kasumi 1, Brtz-induced toxicity was not increased following TRIB2 overexpression supporting the specificity of the compound on the TRIB2-C/EBPα axis. Together these findings provide pre-clinical evidence that TRIB2- expressing AML cells can be pharmacologically targeted with proteasome inhibition due, in part, to blockage of the TRIB2 proteolytic function on C/EBPα p42. A large body of evidence indicates that AML arises through the stepwise acquisition of genetic and epigenetic changes. Mass spectrometry data has identified an interaction between TRIB2 and the epigenetic regulator Protein Arginine Methyltransferase 5 (PRMT5). Following assessment of TRIB2‟s role in AML cell survival and effective targeting of the TRIB2-C/EBPα degradation pathway, a putative TRIB2/PRMT5 cooperation was investigated in order to gain a deeper understanding of the molecular network in which TRIB2 acts as a potent myeloid oncogene. First, a microarray data set was interrogated for PRMT5 expression levels and the primary enzyme responsible for symmetric dimethylation was found to be transcribed at significantly higher levels in AML patients when compared to healthy controls. Next, depletion of PRMT5 in the U937 cell line was shown to reduce the transformative phenotype in the high expressing TRIB2 AML cells, which suggests that PRMT5 and TRIB2 may cooperate to maintain the leukaemogenic potential. Importantly, PRMT5 was identified as a TRIB2-interacting protein by means of a protein tagging approach to purify TRIB2 complexes from 293T cells. These findings trigger further research aimed at understanding the underlying mechanism and the functional significance of this interplay. In summary, the present study provides experimental evidence that TRIB2 has an important oncogenic role in human AML maintenance and, importantly in such a molecularly heterogeneous disease, provides the rational basis to consider proteasome inhibition as an effective targeting strategy for AML patients with high TRIB2 expression. Finally, the identification of PRMT5 as a TRIB2-interacting protein opens a new level of regulation to consider in AML. This work may contribute to our further understanding and therapeutic strategies in acute leukaemias.

The development and field test of a Mealtime Interaction Clinical Observation Tool: a pilot study and clinical research portfolio

Objective: The purpose of this study was to develop and test psychometric properties of a Mealtime Interaction Clinical Observation Tool (MICOT) that could be used to facilitate assessment and behavioural intervention in childhood feeding difficulties. Methods: Thematic analysis of four focus groups with feeding and behaviour experts identified the content and structure of the MICOT. Following refinement, inter-rater reliability was tested between three healthcare professionals. Results: Six themes were identified for the MICOT, which utilises a traffic-light system to identify areas of strength and areas for intervention. Despite poor inter-rater reliability, for which a number of reasons are postulated, some correlation between psychologists’ ratings was evident. Healthcare professionals liked the tool and reported that it could have good clinical utility. Conclusion: The study provides a promising first version of a clinical observation tool that facilitates assessment and behavioural intervention in childhood feeding difficulties.

Parents’ experiences during the transition from childhood to adolescence with Type 1 Diabetes: Parent-child relationships and support received during this time and clinical research portfolio

Background: Type 1 Diabetes (T1D) management often worsens as children become adolescents. This can be a difficult time for parents as they hand over responsibility of diabetes management to their adolescent. Objectives: To look at the experiences of parents with a child with T1D as they move to adolescence and take more responsibility for their diabetes management. To find out about parents’ experience of support during this transition. Subjects: Three parents of adolescents with T1D. Participants were recruited from the NHS Highland Paediatric Diabetes Service. Methods: Participants took part in a one-to-one semi-structured interview with a researcher. Interpretative Phenomenological Analysis was used to analyse the interviews and find common themes across the interviews. Results: Participants experienced worry throughout their child’s transition to adolescence. They found it difficult to let their child take responsibility for their diabetes but acknowledged that their involvement caused tensions with their adolescent. Participants’ experience was that there were a number of practical adjustments to be made with a diagnosis of T1D and educating the network around their child was important. The participants reported that the diagnosis of T1D had an impact on the whole family and not just the child with the diagnosis. The parents felt well supported medically but said that the amount of time before their first clinic appointment felt too long. All participants had concerns about their adolescent moving to the adult diabetic service. Conclusions: Participants experienced worry relating to aspects of their adolescents T1D that they could not control, but were aware of the tensions caused by trying to keep elements of control. Areas of future research were identified.

Attachment Style, Therapeutic Alliance and Recovery in forensic mental health: the A-STAR study and clinical research portfolio

Background: Research suggests that forensic mental health services and staff can play an important role in the recognition and intervention with attachment-related behaviours to promote engagement and recovery. There is a lack of literature exploring whether the attachment needs of forensic service-users are recognised and, associations between attachment style and factors predictive of recovery. Aims: This study aimed to examine the extent to which service-users and keyworkers agree about service-users’ attachment and to identify whether attachment was associated with service attachment, working alliance, ward climate and recovery. Methods: Twenty-two service-users from low and medium secure forensic services, completed questionnaire measures of their attachment style, service attachment, working alliance, ward climate and experiences of recovery. Nineteen keyworkers completed measures of the service-users attachment style and working alliance. Results: There was strong agreement between service-users and staff for attachment anxiety (ICC=0.71) but poor agreement for attachment avoidance (ICC=0.39). Service attachment was associated with more positive perceptions of staff support (r=0.49) and avoidant attachment was associated with lower ratings of recovery (r=-0.51). Correlations between attachment style and service attachment, working alliance and ward climate were small and non-significant. Conclusions: A focus on staff training to support recognition of the nature and impact of avoidant attachment styles is indicated. The findings suggest that interventions to enhance staff - service-user relationships may be important for service attachment and indeed promotion of a recovery focused orientation amongst service-users high in avoidant attachment may improve wellbeing and outcomes.

A preliminary examination of the relationship between compulsive exercise and shame in individuals with an eating disorder: and clinical research portfolio

Objective: To explore the relationship between compulsive exercise and shame in a clinical sample of eating disorder patients. Method: In a cross-sectional study, individuals with an eating disorder (n=21) completed self-report measures of compulsive exercise, internal shame, external shame, bodily shame, anxiety and depression. Results: Internal shame was moderately associated with compulsive exercise (r=.496, p<.05). No further variables were significantly related to compulsive exercise. Individuals with Anorexia-Nervosa and Bulimia-Nervosa did not significantly differ on any of the study variables. Discussion: Hypotheses regarding the possible nature of the relationship between compulsive exercise and shame are suggested. For instance, that compulsive exercise may serve a role in the regulation of internal shame. That compulsive exercise may act as a compensatory behaviour and be a consequence of high levels of shame. Or that internal shame may result as a response to negative perceptions of one’s exercise habits. The results are discussed in line with current literature.