FBXW7ß isoform drives transcriptional activation of the proinflammatory TNF cluster in human pro-B cells.

Noncanonical exon usage plays many important roles in cellular phenotypes, but its contribution to human B-cell development remains sketchily understood. To fill this gap, we collected various B-cell fractions from bone marrow (BM) and tonsil donors, performed RNA sequencing, and examined transcript variants. We identified 150 genes that harbor local splicing variations in all pairwise comparisons. One of them encodes FBXW7, an E3 ubiquitin ligase implicated as a driver in several blood cancers. Surprisingly, we discovered that in normal human pro-B cells, the predominant transcript used an alternative first exon to produce the poorly characterized FBXW7ß isoform, previously thought to be restricted to neural tissues. The FBXW7ß transcript was also abundant in cell lines and primary samples of pediatric B-cell acute lymphoblastic leukemia (B-ALL), which originates in the BM. When overexpressed in a heterologous cell system, this transcript yielded the expected protein product, as judged by anti-FLAG immunoblotting and mass spectrometry. Furthermore, in REH B-ALL cells, FBXW7ß mRNA was the only FBXW7 isoform enriched in the polyribosome fraction. To shed light on possible functions of FBXW7ß, we used gain- and loss-of-function approaches and identified an FBXW7-dependent inflammatory gene signature, apparent in a subset of B-ALL with high FBXW7ß expression. This signature contained several members of the tumor necrosis factor superfamily, including those comprising the HLA Class III cluster (LTB, LST1, NCR3, LTA, and NFKBIL1). Our findings suggest that FBXW7ß expression drives proinflammatory responses, which could contribute to normal B-cell development, leukemogenesis, and responses to anticancer therapies.

Frequency and correlates of suicidal ideation and behaviors in treatment-seeking Post-9/11 Veterans.

OBJECTIVE: Post-9/11 U.S. veterans and servicemembers are at increased risk for suicide, indicating an important need to identify and mitigate suicidal ideation and behaviors in this population. METHOD: Using data modeling techniques, we examined correlates of suicidal ideation and behavior at intake in 261 Post-9/11 veterans and servicemembers seeking mental health treatment. RESULTS: Our sample endorsed high rates of suicidal ideation and behavior. Approximately 40% of our sample scored in a range on the Suicide Behaviors Questionnaire-Revised (SBQ-R), indicating high clinical risk for suicide. Results from multivariate analyses indicate that greater state and/or trait depression severity, greater anger and anger expression, less impulse control, and lower rank were consistently associated with suicidal ideation and behavior across our models. Negative posttraumatic thoughts about the self, gender, and military branch of service were also significantly associated with suicidal ideation and behavior. CONCLUSIONS: Suicidal ideation and behaviors are common in veterans seeking mental health treatment. State and/or trait depression, anger and impulse control were predictors of increased risk for suicidal ideation and behavior across models. Consistencies and differences across models as well as limitations and practical implications for the findings are discussed.

Acquisition, extinction, and return of fear in veterans in intensive outpatient prolonged exposure therapy: A fear-potentiated startle study.

Prolonged exposure (PE) therapy is a first-line treatment for posttraumatic stress disorder (PTSD) and involves repeated presentation of trauma-related cues without aversive outcomes. A primary learning mechanism of PE is fear extinction (new learning that a dangerous cue is now safe) and its retention (maintaining this new learning over time). Extant research suggests extinction is impaired in PTSD patients. In this study, we employed an established fear-potentiated startle-based paradigm to examine fear acquisition, extinction learning and retention before and after completion of intensive outpatient treatment. First, PTSD patients undergoing PE (n = 55) were compared to trauma-exposed patients without PTSD (n = 57). We identified excessive fear in PTSD patients during acquisition and extinction before treatment compared to non-PTSD patients. At post-treatment, we examined the return of fear after extinction in PTSD patients showing high or low treatment response to PE (≥50% change in PTSD symptom severity vs. < 50%). High PE responders maintained fear extinction learning whereas low PE responders showed significant return of fear at post-treatment. These results replicate and extend previous findings of impaired extinction in PTSD and provide support for the proposed theoretical link between fear extinction and PE response.

Targeting CD123 in blastic plasmacytoid dendritic cell neoplasm using allogeneic anti-CD123 CAR T cells.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematologic malignancy with poor outcomes with conventional therapy. Nearly 100% of BPDCNs overexpress interleukin 3 receptor subunit alpha (CD123). Given that CD123 is differentially expressed on the surface of BPDCN cells, it has emerged as an attractive therapeutic target. UCART123 is an investigational product consisting of allogeneic T cells expressing an anti-CD123 chimeric antigen receptor (CAR), edited with TALEN® nucleases. In this study, we examine the antitumor activity of UCART123 in preclinical models of BPDCN. We report that UCART123 have selective antitumor activity against CD123-positive primary BPDCN samples (while sparing normal hematopoietic progenitor cells) in the in vitro cytotoxicity and T cell degranulation assays; supported by the increased secretion of IFNγ by UCART123 cells when cultured in the presence of BPDCN cells. UCART123 eradicate BPDCN and result in long-term disease-free survival in a subset of primary patient-derived BPDCN xenograft mouse models. One potential challenge of CD123 targeting therapies is the loss of CD123 antigen through diverse genetic mechanisms, an event observed in one of three BPDCN PDX studied. In summary, these results provide a preclinical proof-of-principle that allogeneic UCART123 cells have potent anti-BPDCN activity.

Practice review: Evidence-based and effective management of fatigue in patients with advanced cancer.

BACKGROUND: Fatigue affects most patients living with advanced cancer and is a symptom that healthcare professionals can find difficult to manage. AIM: To provide healthcare professionals with a pragmatic overview of approaches to management of fatigue in patients with advanced cancer that are commonly recommended by guidelines and to evaluate evidence underpinning them. DESIGN: Scoping review methodology was used to determine the strength of evidence supporting use of interventions recommended in management of fatigue in patients with advanced cancer. DATA SOURCES: National or international guidelines were examined if they described the management of fatigue in adult cancer patients and were written within the last 6 years (2015-2021) in English. The Cochrane Database of Systematic Reviews (January 2011-December 2021) was searched for 'cancer' AND 'fatigue' in title, abstract or keywords. A PubMed search was also made. RESULTS: Evidence indicates physical exercise interventions are effective and patients may benefit from energy conservation tactics. Evidence does not support use of psychostimulants such as methylphenidate. Limited data were found on efficacy of corticosteroids, psychological interventions, nutritional intervention, sleep optimization or complementary therapies for management of fatigue in advanced cancer. CONCLUSION: We recommend regular assessment, review and acknowledgement of the impact of fatigue. Exercise and energy conservation should be considered. Pharmacological interventions are not endorsed as a routine approach. Many interventions currently recommended by guidelines are not supported by a robust evidence base and further research on their efficacy is required.

Investigating Sex Differences in Rates and Correlates of Food Addiction Status in Women and Men with PTSD.

BACKGROUND: Food addiction (FA) is a dysregulated eating pattern characterized by difficulties in controlling the intake of certain foods. There is an overlap in physical and mental health correlates of FA and post-traumatic stress disorder (PTSD). The purpose of this study was to examine sex differences in the rates of positive FA status in individuals with threshold/subthreshold PTSD, and to examine sex differences in the physical and mental health correlates of FA. METHODS: Post-9/11 veterans/service members seeking PTSD treatment were recruited. Participants were diagnosed with PTSD via the administration of a clinical interview. FA status was determined using Modified Yale Food Addiction Scale-2, binary sex and body mass index were assessed with demographics questions. RESULTS: Nearly half (43%) of the sample were women. There were no sex differences in the rates of FA, with an overall FA prevalence of 18%. There were no sex differences in FA symptom count in the whole sample (M = 1.63) or those with FA status (M = 6.21). Individuals with FA reported higher frequency of disordered eating, higher severity of PTSD, and depression symptoms. CONCLUSIONS: FA should be assessed in tandem with PTSD symptoms, as its prevalence in that sample is higher than in the general population, and it appears to affect both sexes at similar rates.

Impact of intensive treatment programs for posttraumatic stress disorder on suicidal ideation in veterans and service members.

Intensive treatment programs (ITPs) are treating veterans with posttraumatic stress disorder (PTSD) and suicidal ideation (SI). The reduction of SI is a target to the abatement of suicide risk. This study examined whether ITPs utilizing PTSD treatments reduce SI and whether SI reduction is associated with PTSD symptom improvement. Veterans (N = 684) enrolled in a 2-week Prolonged Exposure (PE)-ITP or a 3-week Cognitive Processing Therapy (CPT)-ITP. Study data were drawn from self-report measures [PTSD Checklist for DSM-5 (PCL-5); item 9 of the Patient Health Questionnaire-9 (PHQ-9)] administered at intake and throughout treatment. The ITPs produced large treatment effects for PTSD. SI scores also decreased over time. Lower PTSD symptom severity was associated with less severe SI in both the PE-ITP and CPT-ITP. In conclusion, both PE- and CPT-ITPs effectively treat PTSD and reduce SI among veterans in as little as 2 weeks of intensive PTSD treatment. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

An intensive outpatient program with prolonged exposure for veterans with posttraumatic stress disorder: Retention, predictors, and patterns of change.

High rates of drop-out from treatment of PTSD have challenged implementation. Care models that integrate PTSD focused psychotherapy and complementary interventions may provide benefit in retention and outcome. The first 80 veterans with chronic PTSD enrolled in a 2-week intensive outpatient program combining Prolonged Exposure (PE) and complementary interventions completed symptom and biological measures at baseline and posttreatment. We examined trajectories of symptom change, mediating and moderating effects of a range of patient characteristics. Of the 80 veterans, 77 completed (96.3%) treatment and pre- and posttreatment measures. Self-reported PTSD (p < .001), depression (p < .001) and neurological symptoms (p < .001) showed large reductions with treatment. For PTSD, 77% (n = 59) showed clinically significant reductions. Satisfaction with social function (p < .001) significantly increased. Black veterans and those with a primary military sexual trauma (MST) reported higher baseline severity than white or primary combat trauma veterans respectively but did not differ in their trajectories of treatment change. Greater cortisol response to the trauma potentiated startle paradigm at baseline predicted smaller reductions in PTSD over treatment while greater reductions in this response from baseline to post were associated with better outcomes. Intensive outpatient prolonged exposure combined with complementary interventions shows excellent retention and large, clinically significant reduction in PTSD and related symptoms in two weeks. This model of care is robust to complex presentations of patients with varying demographics and symptom presentations at baseline. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Changes in trauma-potentiated startle, skin conductance, and heart rate within prolonged exposure therapy for PTSD in high and low treatment responders.

While exposure-based psychotherapy is recommended as a first-line treatment for posttraumatic stress disorder (PTSD) given strong evidence for its effectiveness, some patients fail to receive full benefit. Psychophysiological data may be important complementary indices for investigating variability in treatment response and changes over the course of treatment. The focus of the present investigation was to examine change in psychophysiological indices pre- to post-treatment and to investigate if changes differed for high versus low PTSD treatment responders. Participants included veterans with primary PTSD diagnoses who received a two-week intensive prolonged exposure (PE) treatment. Psychophysiological assessment included trauma-potentiated startle, heart rate, and skin conductance recordings during presentation of three standard virtual reality (VR)-based, trauma-relevant scenes presented through a head mounted display. Results indicate that 48.6% were classified as high treatment responders (≥50% reduction in PCL-5 from baseline). Trauma-potentiated startle was observed in all patients at pre-treatment, F = 13.58, p < .001, in that startle magnitude was increased during VR stimuli relative to baseline regardless of responder status. However, in high treatment responders, there was an interaction of VR with time, F = 14.10, p = .001; VR scenes did not potentiate startle post-treatment. Specifically, high treatment responders were less reactive to trauma stimuli following PE treatment. There was no effect of time in the low responder group. Heart rate reactivity data revealed a significant main effect of treatment, F = 45.7, p = .035, but no significant interaction with responder status. Skin conductance reactivity did not significantly change from pre to post-treatment. These results suggest that trauma-potentiated startle may represent an objective marker of fear- and anxiety-related symptom reduction that is sensitive to both traditional outpatient as well as intensive treatment approaches.

Aberrant splicing in B-cell acute lymphoblastic leukemia.

Aberrant splicing is a hallmark of leukemias with mutations in splicing factor (SF)-encoding genes. Here we investigated its prevalence in pediatric B-cell acute lymphoblastic leukemias (B-ALL), where SFs are not mutated. By comparing these samples to normal pro-B cells, we found thousands of aberrant local splice variations (LSVs) per sample, with 279 LSVs in 241 genes present in every comparison. These genes were enriched in RNA processing pathways and encoded ∼100 SFs, e.g. hnRNPA1. HNRNPA1 3'UTR was most pervasively mis-spliced, yielding the transcript subject to nonsense-mediated decay. To mimic this event, we knocked it down in B-lymphoblastoid cells and identified 213 hnRNPA1-regulated exon usage events comprising the hnRNPA1 splicing signature in pediatric leukemia. Some of its elements were LSVs in DICER1 and NT5C2, known cancer drivers. We searched for LSVs in other leukemia and lymphoma drivers and discovered 81 LSVs in 41 additional genes. Seventy-seven LSVs out of 81 were confirmed using two large independent B-ALL RNA-seq datasets, and the twenty most common B-ALL drivers, including NT5C2, showed higher prevalence of aberrant splicing than of somatic mutations. Thus, post-transcriptional deregulation of SF can drive widespread changes in B-ALL splicing and likely contributes to disease pathogenesis.

CD19 Alterations Emerging after CD19-Directed Immunotherapy Cause Retention of the Misfolded Protein in the Endoplasmic Reticulum.

We previously described a mechanism of acquired resistance of B-cell acute lymphoblastic leukemia to CD19-directed chimeric antigen receptor T-cell (CART) immunotherapy. It was based on in-frame insertions in or skipping of CD19 exon 2. To distinguish between epitope loss and defects in surface localization, we used retroviral transduction and genome editing to generate cell lines expressing CD19 exon 2 variants (CD19ex2vs) bearing vesicular stomatitis virus G protein (VSVg) tags. These lines were negative by live-cell flow cytometry with an anti-VSVg antibody and resistant to killing by VSVg-directed antibody-drug conjugates (ADCs), suggestive of a defect in surface localization. Indeed, pulse-chase and α-mannosidase inhibitor assays showed that all CD19ex2vs acquired endoplasmic reticulum (ER)-specific high-mannose-type sugars but not complex-type glycans synthesized in the Golgi apparatus. When fused with green fluorescent protein (GFP), CD19ex2vs (including a mutant lacking the relevant disulfide bond) showed colocalization with ER markers, implying protein misfolding. Mass spectrometric profiling of CD19-interacting proteins demonstrated that CD19ex2vs fail to bind to the key tetraspanin CD81 and instead interact with ER-resident chaperones, such as calnexin, and ER transporters involved in antigen presentation. Thus, even the intact domains of CD19ex2vs cannot be easily targeted with ADCs or current CD19 CARTs but could serve as sources of peptides for major histocompatibility complex (MHC)-restricted presentation and T-cell receptor (TCR)-mediated killing.

In session extinction and outcome in Virtual Reality Exposure Therapy for PTSD.

Recent research emphasizes emotional engagement and between-session extinction, but no longer within-session extinction, as the primary mechanisms underlying exposure therapy for the treatment of PTSD. No previous studies have examined change in subjective units of distress (SUDS) in virtual reality exposure (VRE) for PTSD despite its potential facilitation of engagement (see McLay et al., 2012; Reger & Gahm, 2008). Using in session data from Rothbaum et al. (2014) we examined patterns of within- and between-session SUDS change in veterans receiving VRE for PTSD augmented by d-cycloserine, alprazolam, or placebo. The number of treatment sessions significantly predicted SUDS rating (t = -7.74, p < 0.001). Time in session continued to serve as a significant predictor of SUDS (t = 13.44, p < 0.001). Specifically, engagement increased within session and then reduction (extinction/habituation) was apparent across sessions. Treatment group was a predictor of SUDS rating within treatment sessions (t = 2.26, p < 0.05) but not across sessions, such that participants receiving medication experienced greater increases in SUDS within-session than those receiving placebo. Responder status was a predictor of SUDS reduction across treatment sessions (t = -4.43, p < 0.001) but did not produce an overall or within-session effect on SUDS. Thus, medications impact within-session SUDS changes but do not impact between-session reductions in SUDS- the change most consistently and closely related to magnitude of therapeutic change and responder status.

Krüppel-like factor 4 mediates cellular migration and invasion by altering RhoA activity.

Kru¨ppel like factor 4 (KLF4) is a transcription factor that regulates genes related to differentiation and proliferation. KLF4 also plays a role in metastasis via epithelial to mesenchymal transition. Here, we investigate the function of Klf4 in migration and invasion using mouse embryonic fibroblasts and the RKO human colon cancer cell line. Compared to wild-type, cells lacking Klf4 exhibited increased migration-associated phenotypes. In addition, overexpression of Klf4 in Klf4-/- MEFs attenuated the presence of stress fibers to wild-type levels. An invasion assay suggested that lack of Klf4 resulted in increased invasive capacity. Finally, analysis of RhoA showed elevated RhoA activity in both RKO and MEF cells. Taken together, our results strongly support the novel role of KLF4 in a post-translational regulatory mechanism where KLF4 indirectly modulates the actin cytoskeleton morphology via activity of RhoA in order to inhibit cellular migration and invasion.

Chromatin proteins and RNA are associated with DNA during all phases of mitosis.

Mitosis brings about major changes to chromosome and nuclear structure. We used recently developed proximity ligation assay-based techniques to investigate the association with DNA of chromatin-associated proteins and RNAs in Drosophila embryos during mitosis. All groups of tested proteins, histone-modifying and chromatin-remodeling proteins and methylated histones remained in close proximity to DNA during all phases of mitosis. We also found that RNA transcripts are associated with DNA during all stages of mitosis. Reduction of H3K27me3 levels or elimination of RNAs had no effect on the association of the components of PcG and TrxG complexes to DNA. Using a combination of proximity ligation assay-based techniques and super-resolution microscopy, we found that the number of protein-DNA and RNA-DNA foci undergoes significant reduction during mitosis, suggesting that mitosis may be accompanied by structural re-arrangement or compaction of specific chromatin domains.

Detection of RNA-DNA association by a proximity ligation-based method.

We describe a proximity ligation assay (PLA)-based method of assessing association of DNA and RNA in single cells during the cell cycle. Pulse-labeling of DNA with EdU and RNA with BrU and testing their close proximity by PLA demonstrates that RNA synthesis in individual cells resumes about 30-45 min after DNA replication. Consistent with this conclusion, RNA Pol II phosphorylated at Ser2 of its CTD is detected at the same time as RNA transcripts on nascent DNA. Our results also show that RNA is associated with DNA foci during all stages of mitosis.

Convergence of Acquired Mutations and Alternative Splicing of CD19 Enables Resistance to CART-19 Immunotherapy.

UNLABELLED: The CD19 antigen, expressed on most B-cell acute lymphoblastic leukemias (B-ALL), can be targeted with chimeric antigen receptor-armed T cells (CART-19), but relapses with epitope loss occur in 10% to 20% of pediatric responders. We detected hemizygous deletions spanning the CD19 locus and de novo frameshift and missense mutations in exon 2 of CD19 in some relapse samples. However, we also discovered alternatively spliced CD19 mRNA species, including one lacking exon 2. Pull-down/siRNA experiments identified SRSF3 as a splicing factor involved in exon 2 retention, and its levels were lower in relapsed B-ALL. Using genome editing, we demonstrated that exon 2 skipping bypasses exon 2 mutations in B-ALL cells and allows expression of the N-terminally truncated CD19 variant, which fails to trigger killing by CART-19 but partly rescues defects associated with CD19 loss. Thus, this mechanism of resistance is based on a combination of deleterious mutations and ensuing selection for alternatively spliced RNA isoforms. SIGNIFICANCE: CART-19 yield 70% response rates in patients with B-ALL, but also produce escape variants. We discovered that the underlying mechanism is the selection for preexisting alternatively spliced CD19 isoforms with the compromised CART-19 epitope. This mechanism suggests a possibility of targeting alternative CD19 ectodomains, which could improve survival of patients with B-cell neoplasms.