pH-Weighted amine chemical exchange saturation transfer echo planar imaging visualizes infiltrating glioblastoma cells.

BACKGROUND: Given the invasive nature of glioblastoma, tumor cells exist beyond the contrast-enhancing (CE) region targeted during treatment. However, areas of non-enhancing (NE) tumors are difficult to visualize and delineate from edematous tissue. Amine chemical exchange saturation transfer echo planar imaging (CEST-EPI) is a pH-sensitive molecular magnetic resonance imaging technique that was evaluated in its ability to identify infiltrating NE tumors and prognosticate survival. METHODS: In this prospective study, CEST-EPI was obtained in 30 patients and areas with elevated CEST contrast ("CEST+" based on the asymmetry in magnetization transfer ratio: MTRasym at 3 ppm) within NE regions were quantitated. Median MTRasym at 3 ppm and volume of CEST + NE regions were correlated with progression-free survival (PFS). In 20 samples from 14 patients, image-guided biopsies of these areas were obtained to correlate MTRasym at 3 ppm to tumor and non-tumor cell burden using immunohistochemistry. RESULTS: In 15 newly diagnosed and 15 recurrent glioblastoma, higher median MTRasym at 3ppm within CEST + NE regions (P = .007; P = .0326) and higher volumes of CEST + NE tumor (P = .020; P < .001) were associated with decreased PFS. CE recurrence occurred in areas of preoperative CEST + NE regions in 95.4% of patients. MTRasym at 3 ppm was correlated with presence of tumor, cell density, %Ki-67 positivity, and %CD31 positivity (P = .001; P < .001; P < .001; P = .001). CONCLUSIONS: pH-weighted amine CEST-EPI allows for visualization of NE tumor, likely through surrounding acidification of the tumor microenvironment. The magnitude and volume of CEST + NE tumor correlates with tumor cell density, degree of proliferating or "active" tumor, and PFS.

Comparative Effectiveness of Psychotherapy vs Antidepressants for Depression in Heart Failure: A Randomized Clinical Trial.

Importance: Heart failure (HF) affects more than 6 million adults in the US and more than 64 million adults worldwide, with 50% prevalence of depression. Patients and clinicians lack information on which interventions are more effective for depression in HF. Objective: To compare the effectiveness of behavioral activation psychotherapy (BA) vs antidepressant medication management (MEDS) on patient-centered outcomes inpatients with HF and depression. Design, Setting, and Participants: This pragmatic randomized comparative effectiveness trial was conducted from 2018 to 2022, including 1-year follow-up, at a not-for-profit academic health system serving more than 2 million people from diverse demographic, socioeconomic, cultural, and geographic backgrounds. Participant included inpatients and outpatients diagnosed with HF and depression, and data were analyzed as intention-to-treat. Data were analyzed from 2022 to 2023. Interventions: BA is an evidence-based manualized treatment for depression, promoting engagement in personalized pleasurable activities selected by patients. MEDS involves the use of an evidence-based collaborative care model with care managers providing coordination with patients, psychiatrists, and primary care physicians to only administer medications. Main Outcomes and Measures: The primary outcome was depressive symptom severity at 6 months, measured using the Patient Health Questionnaire 9-Item (PHQ-9). Secondary outcomes included physical and mental health-related quality of life (HRQOL), measured using the Short-Form 12-Item version 2 (SF-12); heart failure-specific HRQOL, measured using the Kansas City Cardiomyopathy Questionnaire; caregiver burden, measured with the Caregiver Burden Questionnaire for Heart Failure; emergency department visits; readmissions; days hospitalized; and mortality at 3, 6, and 12 months. Results: A total of 416 patients (mean [SD] age, 60.71 [15.61] years; 243 [58.41%] male) were enrolled, with 208 patients randomized to BA and 208 patients randomized to MEDS. At baseline, mean (SD) PHQ-9 scores were 14.54 (3.45) in the BA group and 14.31 (3.60) in the MEDS group; both BA and MEDS recipients experienced nearly 50% reduction in depressive symptoms at 3, 6, and 12 months (eg, mean [SD] score at 12 months: BA, 7.62 (5.73); P < .001; MEDS, 7.98 (6.06); P < .001; between-group P = .55). There was no statistically significant difference between BA and MEDS in the primary outcome of PHQ-9 at 6 months (mean [SD] score, 7.53 [5.74] vs 8.09 [6.06]; P = .88). BA recipients, compared with MEDS recipients, experienced small improvement in physical HRQOL at 6 months (mean [SD] SF-12 physical score: 38.82 [11.09] vs 37.12 [10.99]; P = .04), had fewer ED visits (3 months: 38% [95% CI, 14%-55%] reduction; P = .005; 6 months: 30% [95% CI, 14%-40%] reduction; P = .008; 12 months: 27% [95% CI, 15%-38%] reduction; P = .001), and spent fewer days hospitalized (3 months: 17% [95% CI, 8%-25%] reduction; P = .002; 6 months: 19% [95% CI, 13%-25%] reduction; P = .005; 12 months: 36% [95% CI, 32%-40%] reduction; P = .001). Conclusions and Relevance: In this comparative effectiveness trial of BA and MEDS in patients with HF experiencing depression, both treatments significantly reduced depressive symptoms by nearly 50% with no statistically significant differences between treatments. BA recipients experienced better physical HRQOL, fewer ED visits, and fewer days hospitalized. The study findings suggested that patients with HF could be given the choice between BA or MEDS to ameliorate depression. Trial Registration: ClinicalTrials.gov Identifier: NCT03688100.

Single-nucleus expression characterization of non-enhancing region of recurrent high-grade glioma.

Background: Non-enhancing (NE) infiltrating tumor cells beyond the contrast-enhancing (CE) bulk of tumor are potential propagators of recurrence after gross total resection of high-grade glioma. Methods: We leveraged single-nucleus RNA sequencing on 15 specimens from recurrent high-grade gliomas (n = 5) to compare prospectively identified biopsy specimens acquired from CE and NE regions. Additionally, 24 CE and 22 NE biopsies had immunohistochemical staining to validate RNA findings. Results: Tumor cells in NE regions are enriched in neural progenitor cell-like cellular states, while CE regions are enriched in mesenchymal-like states. NE glioma cells have similar proportions of proliferative and putative glioma stem cells relative to CE regions, without significant differences in % Ki-67 staining. Tumor cells in NE regions exhibit upregulation of genes previously associated with lower grade gliomas. Our findings in recurrent GBM paralleled some of the findings in a re-analysis of a dataset from primary GBM. Cell-, gene-, and pathway-level analyses of the tumor microenvironment in the NE region reveal relative downregulation of tumor-mediated neovascularization and cell-mediated immune response, but increased glioma-to-nonpathological cell interactions. Conclusions: This comprehensive analysis illustrates differing tumor and nontumor landscapes of CE and NE regions in high-grade gliomas, highlighting the NE region as an area harboring likely initiators of recurrence in a pro-tumor microenvironment and identifying possible targets for future design of NE-specific adjuvant therapy. These findings also support the aggressive approach to resection of tumor-bearing NE regions.

Pathway-based approach reveals differential sensitivity to E2F1 inhibition in glioblastoma.

Analysis of tumor gene expression is an important approach for the classification and identification of therapeutic vulnerabilities. However, targeting glioblastoma (GBM) based on molecular subtyping has not yet translated into successful therapies. Here, we present an integrative approach based on molecular pathways to expose new potentially actionable targets. We used gene set enrichment analysis (GSEA) to conduct an unsupervised clustering analysis to condense the gene expression data from bulk patient samples and patient-derived gliomasphere lines into new gene signatures. We identified key targets that are predicted to be differentially activated between tumors and were functionally validated in a library of gliomasphere cultures. Resultant cluster-specific gene signatures associated not only with hallmarks of cell cycle and stemness gene expression, but also with cell-type specific markers and different cellular states of GBM. Several upstream regulators, such as PIK3R1 and EBF1 were differentially enriched in cells bearing stem cell like signatures and bear further investigation. We identified the transcription factor E2F1 as a key regulator of tumor cell proliferation and self-renewal in only a subset of gliomasphere cultures predicted to be E2F1 signaling dependent. Our in vivo work also validated the functional significance of E2F1 in tumor formation capacity in the predicted samples. E2F1 inhibition also differentially sensitized E2F1-dependent gliomasphere cultures to radiation treatment. Our findings indicate that this novel approach exploring cancer pathways highlights key therapeutic vulnerabilities for targeting GBM.

Dppa2/4 Facilitate Epigenetic Remodeling during Reprogramming to Pluripotency.

As somatic cells are converted into induced pluripotent stem cells (iPSCs), their chromatin is remodeled to a pluripotent configuration with unique euchromatin-to-heterochromatin ratios, DNA methylation patterns, and enhancer and promoter status. The molecular machinery underlying this process is largely unknown. Here, we show that embryonic stem cell (ESC)-specific factors Dppa2 and Dppa4 play a key role in resetting the epigenome to a pluripotent state. They are induced in reprogramming intermediates, function as a heterodimer, and are required for efficient reprogramming of mouse and human cells. When co-expressed with Oct4, Klf4, Sox2, and Myc (OKSM) factors, Dppa2/4 yield reprogramming efficiencies that exceed 80% and accelerate reprogramming kinetics, generating iPSCs in 2 to 4 days. When bound to chromatin, Dppa2/4 initiate global chromatin decompaction via the DNA damage response pathway and contribute to downregulation of somatic genes and activation of ESC enhancers, all of which enables an efficient transition to pluripotency. Our work provides critical insights into how the epigenome is remodeled during acquisition of pluripotency.