ARF4-mediated retrograde trafficking as a driver of chemoresistance in GBM.

BACKGROUND: Cellular functions hinge on the meticulous orchestration of protein transport, both spatially and temporally. Central to this process is retrograde trafficking, responsible for targeting proteins to the nucleus. Despite its link to many diseases, the implications of retrograde trafficking in glioblastoma (GBM) are still unclear. METHODS: To identify genetic drivers of TMZ resistance, we conducted comprehensive CRISPR-knockout screening, revealing ADP-ribosylation factor 4 (ARF4), a regulator of retrograde trafficking, as a major contributor. RESULTS: Suppressing ARF4 significantly enhanced TMZ sensitivity in GBM patient-derived xenograft (PDX) models, leading to improved survival rates (p<0.01) in both primary and recurrent lines. We also observed that TMZ exposure stimulates ARF4-mediated retrograde trafficking. Proteomics analysis of GBM cells with varying levels of ARF4 unveiled the influence of this pathway on EGFR signaling, with increased nuclear trafficking of EGFR observed in cells with ARF4 overexpression and TMZ treatment. Additionally, spatially-resolved RNA-sequencing of GBM patient tissues revealed substantial correlations between ARF4 and crucial nuclear EGFR (nEGFR) downstream targets, such as MYC, STAT1, and DNA-PK. Decreased activity of DNA-PK, a DNA repair protein downstream of nEGFR signaling that contributes to TMZ resistance, was observed in cells with suppressed ARF4 levels. Notably, treatment with DNA-PK inhibitor, KU57788, in mice with a recurrent PDX line resulted in prolonged survival (p<0.01), highlighting the promising therapeutic implications of targeting proteins reliant on ARF4-mediated retrograde trafficking. CONCLUSION: Our findings demonstrate that ARF4-mediated retrograde trafficking contributes to the development of TMZ resistance, cementing this pathway as a viable strategy to overcome chemoresistance in GBM.

Development of core sets for deafblindness: an international expert survey on functioning and disability of individuals living with deafblindness using the International Classification of Functioning, Disability, and Health.

BACKGROUND: The development of International Classification of Functioning, Disability, and Health (ICF) Core Sets greatly enhances the global recognition of health conditions, thereby advancing research, education, and care provision. Aside from the work of researchers, and the viewpoint of persons with lived experience, the development of Core Sets for deafblindness needs to include the viewpoints of professionals with expertise unique to this condition. AIM: To represent the perspective of health and social service expert professionals in the development of ICF Core Sets for deafblindness. DESIGN: Cross-sectional cohort study. SETTING: Global online survey representing all six regions of the World Health Organization. POPULATION: One hundred and five professionals providing and health or social service to individuals living with deafblindness with a minimum of 2 years of work experience with this population. METHODS: An online survey was distributed through professional networks and social media for individuals working with persons living with deafblindness. Demographic items were summarized using descriptive statistics. Six open-ended questions explored the perceptions of body functions and structures that influence activities and participation, as well as environmental and personal factors that facilitate functioning. Data were linked to the ICF codes using established linking rules and procedures. RESULTS: The 2934 survey response units were linked using IFC categories. Of the 421 unique categories, 133 were used by 5% or more of respondents. Most categories within the Activities and Participation component were equally emphasized. The most frequent Environmental factors were support and relationships, services, systems, and policies, as well as and the physical environment (e.g., hearing aids or noise). Mental functions, including higher level cognitive functions, temperament and personality were frequently emphasized. CONCLUSIONS: Almost three quarters (73.3%) of the entire ICF classification categories were included in the expert survey results. This proportion emphasizes the importance of a multidimensional tool, such as the ICF, for assessing functioning and health for persons with deafblindness. CLINICAL REHABILITATION IMPACT: The representation of this professional perspective in Core Set development will improve standardized assessment and documentation, intervention planning, and facilitate interprofessional communication with the goal of improving person-centered care for persons living with deafblindness.

Immunobiology and Cytokine Modulation of the Pediatric Brain Tumor Microenvironment: A Scoping Review.

Utilizing a Scoping Review strategy in the domain of immune biology to identify immune therapeutic targets, knowledge gaps for implementing immune therapeutic strategies for pediatric brain tumors was assessed. The analysis demonstrated limited efforts to date to characterize and understand the immunological aspects of tumor biology with an over-reliance on observations from the adult glioma population. Foundational knowledge regarding the frequency and ubiquity of immune therapeutic targets is an area of unmet need along with the development of immune-competent pediatric tumor models to test therapeutics and especially combinatorial treatment. Opportunities arise in the evolution of pediatric tumor classification from histological to molecular with targeted immune therapeutics.

The International Classification of Functioning, Disability and Health Core Set for deafblindness. Part I: a systematic review of outcome measures.

INTRODUCTION: The International Classification of Functioning, Disability, and Health (ICF), developed by the World Health Organization, is a classification framework that focuses on the health and functioning of people with disabilities. As part of an ICF Core Set development, four studies need to be conducted, one of which is a systematic review. This study presents part 1 of the systematic review that aims to describe the outcome measures identified in the literature related to functioning in individuals with deafblindness. EVIDENCE ACQUISITION: The research team screened articles from eight scientific databases, three journals, and Google Scholar (March 2011 to September 2022). Articles were included if they studied individuals with deafblindness aged 18 and older. Studies that examined genetics or laboratory experiments involving animals were excluded. Data were extracted into a logbook with key descriptors such as study location and design, age of study population, and instruments/outcome measures used, which were further categorized into one of the following types: 1) standardized; 2) patient-reported measures, standardized (PT-S); 3) patient-reported measures, not standardized (PT-not S); 4) health professional, reported measures, standardized (HP-S); 5) Technical measures; 6) other measures (parent-reported standardized and laboratory measures). EVIDENCE SYNTHESIS: The review included 147 studies, of which most were conducted in Europe (47.6%) and North America (27.9%). Of the 314 identified outcome measures, 57 were Standardized, 59 were Patient Reported-Standardized (PT-S), 178 were patient reported non-standardized (PT-Not S) variables, 11 were health professional reported, standardized, five were technical, and four were classified as other measures. CONCLUSIONS: Most instruments measured functioning in daily activities and the mental health of individuals with deafblindness. Three deafblind-specific instruments were identified in this study, highlighting the need for more deafblind-specific instruments to be developed and utilized in research.

Ribonucleotide reductase regulatory subunit M2 drives glioblastoma TMZ resistance through modulation of dNTP production.

During therapy, adaptations driven by cellular plasticity are partly responsible for driving the inevitable recurrence of glioblastoma (GBM). To investigate plasticity-induced adaptation during standard-of-care chemotherapy temozolomide (TMZ), we performed in vivo single-cell RNA sequencing in patient-derived xenograft (PDX) tumors of GBM before, during, and after therapy. Comparing single-cell transcriptomic patterns identified distinct cellular populations present during TMZ therapy. Of interest was the increased expression of ribonucleotide reductase regulatory subunit M2 (RRM2), which we found to regulate dGTP and dCTP production vital for DNA damage response during TMZ therapy. Furthermore, multidimensional modeling of spatially resolved transcriptomic and metabolomic analysis in patients' tissues revealed strong correlations between RRM2 and dGTP. This supports our data that RRM2 regulates the demand for specific dNTPs during therapy. In addition, treatment with the RRM2 inhibitor 3-AP (Triapine) enhances the efficacy of TMZ therapy in PDX models. We present a previously unidentified understanding of chemoresistance through critical RRM2-mediated nucleotide production.

Neurologic Manifestations of Long COVID Differ Based on Acute COVID-19 Severity.

OBJECTIVE: To characterize neurologic manifestations in post-hospitalization Neuro-PASC (PNP) and non-hospitalized Neuro-PASC (NNP) patients. METHODS: Prospective study of the first 100 consecutive PNP and 500 NNP patients evaluated at a Neuro-COVID-19 clinic between 5/2020 and 8/2021. RESULTS: PNP were older than NNP patients (mean 53.9 vs 44.9 y; p < 0.0001) with a higher prevalence of pre-existing comorbidities. An average 6.8 months from onset, the main neurologic symptoms were "brain fog" (81.2%), headache (70.3%), and dizziness (49.5%) with only anosmia, dysgeusia and myalgias being more frequent in the NNP compared to the PNP group (59 vs 39%, 57.6 vs 39% and 50.4 vs 33%, all p < 0.003). Moreover, 85.8% of patients experienced fatigue. PNP more frequently had an abnormal neurologic exam than NNP patients (62.2 vs 37%, p < 0.0001). Both groups had impaired quality of life in cognitive, fatigue, sleep, anxiety, and depression domains. PNP patients performed worse on processing speed, attention, and working memory tasks than NNP patients (T-score 41.5 vs 55, 42.5 vs 47 and 45.5 vs 49, all p < 0.001) and a US normative population. NNP patients had lower results in attention task only. Subjective impression of cognitive ability correlated with cognitive test results in NNP but not in PNP patients. INTERPRETATION: PNP and NNP patients both experience persistent neurologic symptoms affecting their quality of life. However, they harbor significant differences in demographics, comorbidities, neurologic symptoms and findings, as well as pattern of cognitive dysfunction. Such differences suggest distinct etiologies of Neuro-PASC in these populations warranting targeted interventions. ANN NEUROL 2023;94:146-159.

Spelling Out CICs: A Multi-Organ Examination of the Contributions of Cancer Initiating Cells' Role in Tumor Progression.

Tumor invasion and metastasis remain the leading causes of mortality for patients with cancer despite current treatment strategies. In some cancer types, recurrence is considered inevitable due to the lack of effective anti-metastatic therapies. Recent studies across many cancer types demonstrate a close relationship between cancer-initiating cells (CICs) and metastasis, as well as general cancer progression. First, this review describes CICs' contribution to cancer progression. Then we discuss our recent understanding of mechanisms through which CICs promote tumor invasion and metastasis by examining the role of CICs in each stage. Finally, we examine the current understanding of CICs' contribution to therapeutic resistance and recent developments in CIC-targeting drugs. We believe this understanding is key to advancing anti-CIC clinical therapeutics.

AMA Code of Medical Ethics' Opinions Related to Palliative Surgical Care.

The AMA Code of Medical Ethics offers guidance on the significance of palliative surgical care in Opinion 5.6, "Sedation to Unconsciousness in End-of-Life Care," and Opinion 5.5, "Medically Ineffective Interventions." The American Medical Association's House of Delegates policies further outline ways in which physicians should navigate palliative care intervention through spreading awareness of and advancing research on palliative care and improving reimbursement practices. This article defines palliative care, examines the risks associated with palliative surgery, and discusses AMA Code guidance.

LNX1 Modulates Notch1 Signaling to Promote Expansion of the Glioma Stem Cell Population during Temozolomide Therapy in Glioblastoma.

Glioblastoma (GBM) is the most common primary brain malignancy in adults, with a 100% recurrence rate and 21-month median survival. Our lab and others have shown that GBM contains a subpopulation of glioma stem cells (GSCs) that expand during chemotherapy and may contribute to therapeutic resistance and recurrence in GBM. To investigate the mechanism behind this expansion, we applied gene set expression analysis (GSEA) to patient-derived xenograft (PDX) cells in response to temozolomide (TMZ), the most commonly used chemotherapy against GBM. Results showed significant enrichment of cancer stem cell and cell cycle pathways (False Discovery Rate (FDR) < 0.25). The ligand of numb protein 1 (LNX1), a known regulator of Notch signaling by targeting negative regulator Numb, is strongly upregulated after TMZ therapy (p < 0.0001) and is negatively correlated with survival of GBM patients. LNX1 is also upregulated after TMZ therapy in multiple PDX lines with concomitant downregulations in Numb and upregulations in intracellular Notch1 (NICD). Overexpression of LNX1 results in Notch1 signaling activation and increased GSC populations. In contrast, knocking down LNX1 reverses these changes, causing a significant downregulation of NICD, reduction in stemness after TMZ therapy, and resulting in more prolonged median survival in a mouse model. Based on this, we propose that during anti-GBM chemotherapy, LNX1-regulated Notch1 signaling promotes stemness and contributes to therapeutic resistance.