In-Press Preview
Articles in this category appear as authors submitted them for publication, prior to copyediting and publication layout.
Abstract
Systemic inflammation is now recognized as a key contributor to epilepsy pathophysiology, yet the role of innate immune cells, particularly neutrophils, remains poorly defined in epilepsy. While preclinical studies in rodent models have implicated neutrophils in seizure activity, their phenotype in human epilepsy has not been thoroughly investigated. In this study, we aimed to characterize systemic inflammatory profiles and neutrophil-associated immune signatures in the blood of patients with drug-resistant epilepsy, compared to healthy controls. We identified a systemic low-grade inflammatory profile in patients, characterized by elevated neutrophil-to-lymphocyte ratio, C-reactive protein, pro-inflammatory cytokines (IL-6, CXCL8/IL-8, TNF-α), and activated neutrophils (CXCR4+CD62Llow). Neutrophil phenotyping revealed two distinct immune profiles. Patients with longer disease duration exhibited a more immature systemic signature, characterized by immature neutrophils (CD15⁺CD10⁻), resting neutrophils (CXCR4⁺CD62L⁺), and elevated IL-6 levels. In contrast, patients with higher seizure frequency displayed a more inflammatory profile, marked by increased IL-12 and activated (CXCR4+CD62Llow) and hyperactivated (CXCR4highCD62Llow) neutrophil subsets. Moreover, elevated pre-surgical levels of inflammatory profile TNF-α, IL-6, and hyperactivated CXCR4high CD62Llow neutrophils were associated with seizure recurrence one year after surgery. This pioneering study highlights the heterogeneity of peripheral immune responses in drug-resistant epilepsy and identifies neutrophil-related signatures as promising prognostic biomarkers in this context.
Authors
Coraly Simoës Da Gama, Aurelie Hanin, Gwen Goudard, Veronique Masson, Aurore Besnard, Karim Dorgham, Guy Gorochov, Guillaume Dorothee, Valerio Frazzini, Vincent Navarro, Mélanie Morin-Brureau
Abstract
The physician-scientist career has historically progressed through individual persistence and improvisation, as physician-scientists have navigated the demands of clinical practice combined with biomedical research without a clearly structured path. While this approach has sustained the field for several decades, individual determination is increasingly insufficient in the current climate, given the growing complexity within both clinical and research training, as well as potential disruptions to research funding and health care reimbursement. The 2025 ASCI / AAIM / Burroughs Wellcome Fund Physician-Scientist Pathways Workshop convened national leaders and faculty at all career stages to assess existing structures and envision new and more deliberate approaches. Discussions highlighted the impact of NIH initiatives in supporting early careers, institutional vulnerabilities, and need for intentional investments in physician-scientist careers. Breakout sessions emphasized the importance of dedicated funding for physician-scientist pathways, mentorship, social supports, and national benchmarks for compensation and promotion for this unique career pathway. The physician-scientist career path now stands at a crossroads. Going forward, sustained investment, longer and more flexible funding mechanisms such as the R37 and R35 Maximizing Investigators’ Research Award (MIRA) programs, and transparent standards are required. Federal funding alone cannot ensure the stability of a physician-scientist’s career; therefore, new approaches and commitments from academic health centers, philanthropy, and industry will be essential to ensure the viability of this career. With coordinated, intentional strategic planning, the physician-scientist workforce can thrive and remain a driver of America’s biomedical research future.
Authors
Christopher S. Williams, Emily J. Gallagher, Daniel P. Cook, David Mankoff, Rebecca M. Baron, Christopher Pittenger, Jatin M. Vyas, Don C. Rockey, Patrick J. Hu, Ashley L. Steed, W. Kimryn Rathmell, Jeffrey R. Balser, Nancy J. Brown, John M. Carethers, Jonathan A. Epstein, Keith A. Choate, Peter J. Gruber, Tiffany C. Scharschmidt, Kyu Rhee
Abstract
Malnutrition, gut inflammation, and antibiotic-induced dysbiosis (AID) are well-recognized risk factors for poor clinical outcomes among critically ill patients. We previously showed that commercially available plant-based enteral nutrition (PBEN) preserves a commensal microbiome compared with commonly used artificial enteral nutrition (AEN). In this study, PBEN was superior to AEN in promoting recovery from antibiotic-induced dysbiosis in mice and humans. PBEN effectively mitigated anemia and leukopenia, restored naïve lymphocyte populations, and reduced bone marrow myeloid expansion. Animals randomized to PBEN also exhibited improved responses to infectious challenges following antibiotic exposure. A pilot clinical study validated these findings, demonstrating increased gut commensals, reduced pathogens, and improved leukocyte balance in critically ill children receiving PBEN compared with AEN. Together, these results suggest that PBEN offers a practical dietary approach to mitigate antibiotic-associated complications and potentially improve clinical outcomes among hospitalized patients requiring supplemental nutrition.
Authors
Mona Chatrizeh, Jianmin Tian, Matthew Rogers, Firuz Feturi, Guojun Wu, Brian Firek, Roman Nikonov, Lauren Cass, Alexandra Sheppeck, Lavnish Ojha, Ali Carroll, Matthew Henkel, Justin Azar, Rajesh K. Aneja, Brian Campfield, Dennis Simon, Michael J. Morowitz
Abstract
Heart failure with preserved ejection fraction (HFpEF) is a multifactorial disease that develops in several clinical settings. Despite its complex pathogenesis, evidence indicates a central role for fibrosis in the progression of left ventricular (LV) diastolic dysfunction (LVDD). Through exploratory research into brown adipose tissue (BAT)-derived adipokines (BATokines), we identified a secreted-type pro-fibrotic protein, procollagen C-endopeptidase enhancer-1 (PCPE-1), whose expression increased in BAT with aging. PCPE-1 promotes the cleavage of procollagens and is a critical initiator of fibrillogenesis. This molecule was increased in the plasma of aged mice. In addition to aging, dietary obesity led to an increase in PCPE-1 expression in the LV of mice. Both systemic and BAT-specific PCPE-1 depletion ameliorated LV fibrosis and LVDD in the obese HFpEF model. Our data also showed that age-associated LVDD was ameliorated in the systemic PCPE-1 knockout mouse model fed with a normal chow diet. Conversely, the overexpression of PCPE-1 expression in BAT was shown to lead to aggravation of LV fibrosis and LVDD. Mechanistically, we found reactive oxygen species (ROS)/DNA damage/c-Fos/c-Jun signaling resulted in an increased production of PCPE-1 in brown adipocytes. These results indicate PCPE-1 may represent a druggable target for aging- and obesity-related HFpEF.
Authors
Yung-Ting Hsiao, Yohko Yoshida, Hirotsugu Tsuchimochi, Jingyuan Tang, Tin May Aung, Chun-Han Chang, Agian Jeffilano Barinda, Zhihong Li, Nur Syakirah Binti Othman, Tom Yoshizaki, Yiwei Ling, Shujiro Okuda, Manabu Abe, Seiya Mizuno, Satoru Takahashi, Takayuki Inomata, Hidetaka Kioka, Yasushi Sakata, Daichi Maeda, Yuya Matsue, Takaaki Furihata, Hiroshi Iwata, James T. Pearson, Kinya Otsu, Kenneth Walsh, Akihito Ishigami, Tohru Minamino, Ippei Shimizu
Loss of Tumor-Infiltrating Lymphocytes and Poor Response to Immunotherapy in IDH GOF Mutant Melanoma
Abstract
Recent innovations in melanoma treatment with immune checkpoint blockade (ICB) have improved overall outcomes for patients, however over 50% of patients still develop resistance to treatment. These patients either have intrinsic resistance, and never respond to therapy, or develop acquired resistance months or years into treatment. The mechanisms underlying ICB resistance remain poorly understood. Our data shows that isocitrate dehydrogenase gain of function (IDH GOF) mutant melanoma patients have a worse response to anti-PD1 immunotherapy. IDH mutations have been found to be oncogenic and associated with differential methylation in multiple cancers but are not yet characterized in human melanoma. Here, we investigate the clinical, immune, and transcriptional phenotypes of IDH GOF melanomas through analyses of clinical response, single-cell RNA sequencing, bulk RNA sequencing, and DNA methylation data. Single-cell data analysis shows decreased immune infiltrate and activity in the IDH GOF tumors. Bulk sequencing data demonstrates the association between IDH mutation, immune exclusion, and disruptions in global DNA methylation. The melanoma-derived genomic data presented supports previously described resistance mechanisms of IDH mutation in other cancer types and is the first demonstration of the role of IDH GOF in the human melanoma tumor microenvironment.
Authors
Emma Specht, Lakshmi Pakanati, Meng-Ju Wu, Russell W. Jenkins, Derek N. Effiom, Nabeel Bardeesy, Bradley E. Bernstein, Moshe Sade-Feldman, Christine G. Lian, Genevieve M. Boland, Elena Torlai Triglia, Sonia Cohen
Abstract
X-linked myotubular myopathy (XLMTM) is a rare genetic disorder that typically presents at birth with progressive muscle weakness and respiratory difficulties and is caused by myotubularin-1 (MTM1) gene mutations. Here we examine the role of phosphatidylinositol-4-phosphate 3-kinase catalytic subunit type 2 beta (PIK3C2B), a lipid kinase that interacts with MTM1, in XLMTM in various models. We examined the effect of BLU3797, a novel, highly potent, selective, orally bioavailable PIK3C2B inhibitor, on survival, muscle development, myofiber phenotypes, and gene expression in MTM1-/y mice. PIK3C2B-deficient XLMTM animals demonstrated increased survival, restored muscle function, fewer myofibers with centralized nuclei, and normalization of disease-associated molecular markers. BLU3797 alleviated the XLMTM phenotype in a dose-dependent and reversible manner. Loss of functional PIK3C2B in XLMTM mice promoted a more differentiated, adult-like myofiber profile, which was strongly associated with normalization of disease surrogates and a reduction in markers of early muscle development and regeneration. BLU3797 treatment appears to modulate the expression of microRNAs associated with satellite cell activation and myofiber fusion. These findings indicate that PIK3C2B inhibition with BLU3797 effectively reverses the XLMTM disease phenotype by enhancing muscle function and promoting development toward a more mature state.
Authors
Andrew Shearer, Melissa L. Brooks, Maxine M. Chen, Thiwanka Samarakoon, John Hsieh, Gramoz Kondakci, Emanuele Perola, Jason Brubaker, Kristina Fetalvero, Stefanie Schalm, Joana Caetano-Lopes
Abstract
Cytotoxic chemotherapy primarily targets rapidly proliferating cancer cells but also depletes normal myeloid cells. The resulting cell loss triggers reactive myelopoiesis, a compensatory process in which hematopoietic stem and progenitor cells (HSPCs) in the bone marrow (BM) regenerate myeloid lineages. We previously showed that the alkylating agent cyclophosphamide (CTX) induces myelopoiesis leading to the expansion of immunosuppressive monocytes in mice. However, the molecular features and clinical relevance of these cells remain poorly understood. Here, we report the emergence of immunosuppressive monocytes in the peripheral blood of lymphoma patients receiving CTX-containing chemotherapy. To gain mechanistic insight into CTX-induced myelopoiesis, we performed single-cell RNA sequencing (scRNA-seq) and assay for transposase-accessible chromatin using sequencing (ATAC-seq) on BM monocytes from CTX-treated mice. These analyses revealed a heterogeneous monocyte population and demonstrated that CTX skews myelopoiesis toward the generation of neutrophil-like monocytes (NeuMo). Moreover, CTX-induced NeuMo cells, enriched within the CXCR4⁺CX3CR1⁻ monocyte subset, exhibited potent T-cell suppressive activity. Using the NeuMo gene signature, reanalysis of public scRNA-seq datasets identified a transcriptionally similar monocyte subset in chemotherapy-treated cancer patients. Collectively, our findings suggest that the expansion of NeuMo-like cells following chemotherapy represents a conserved immunoregulatory feedback mechanism with potential impact on tumor response to chemoimmunotherapy.
Authors
Huidong Shi, Zhi-Chun Ding, Ogacheko D. Okoko, Xin Wang, George Zhou, Yan Ye, Md Yeashin Gazi, Caitlin Brandle, Lirong Pei, Rafal Pacholczyk, Catherine C. Hedrick, Locke J. Bryan, Gang Zhou
Abstract
Chronic neuropathic pain is frequently comorbid with anxiety disorders, yet the neural circuits underlying this interaction remain poorly defined. The parafascicular nucleus of the thalamus (PF) integrates nociceptive and affective signals, but its specific regulatory mechanisms in pain-anxiety comorbidity are not well known. Using spared nerve injury (SNI) model mice, we combined viral neural tracing, chemogenetics, pharmacology, and electrophysiology to dissect the locus coeruleus (LC)-PF neural pathway. Viral tracing revealed monosynaptic projections from norepinephrinergic (NEergic) neurons in the dorsal LC to calcium/calmodulin dependent protein kinase IIα (CaMKIIα)- immunopositive neurons within the PF. Chemogenetic inhibition/activation of this pathway were performed in naïve and SNI mice, alongside intra-PF microinjection of the alpha-2 adrenergic receptor (ADRA2) antagonist yohimbine. Behavioral tests assessed mechanical/thermal hypersensitivity and anxiety-like behaviors. Results showed that 92.1% of PF-projecting LC neurons were NEergic, with 70.1% localized dorsally. Chemogenetic inhibition of LCNE-PFCaMKIIα neural pathway significantly alleviated both acute-phase mechanical hypersensitivity (< 7 days post-surgery) and chronic-phase anxiety-like behaviors in SNI mice, while activation of this pathway induced pain sensitization and anxiety-like behaviors in naïve mice. Intra-PF yohimbine reversed SNI-induced allodynia and anxiety-like behaviors. Electrophysiology confirmed yohimbine increased PF neuronal intrinsic excitability. These results suggest that the LCNE-PFCaMKIIα neural pathway promotes neuropathic pain and comorbid anxiety via ADRA2-mediated suppression of PF neuronal activity. Targeted inhibition of this circuit may represent a therapeutic strategy for pain-related affective disorders.
Authors
Zhong-Yi Liu, Fei Li, Li-Ming Liu, Yao-Hua Liu, Jia Li, Zi-Ang Li, Jin Cheng, Tian-Yu Zhao, Hui-Min Tian, Dong-Ning Li, Sha-Sha Tao, Hui Li, Fen-Sheng Huang, Yun-Qing Li
Abstract
Subendothelial retention of cholesterol-rich apolipoprotein-B-containing lipoproteins drives atherosclerotic arterial disease. In peripheral interstitial fluid from patients with type 2 diabetes (T2D), levels of such particles have been shown to be paradoxically reduced relative to those in serum, presumably reflecting their increased retention within the arterial wall. To identify possible mechanisms involved in lipoprotein retention in T2D, we obtained serum and skin blister fluid from such patients and matched controls, together with skin biopsies in a subset of individuals. In T2D, smaller LDL and VLDL remnant particles were more prominent in serum, but not in interstitial fluid, reflecting their enhanced vascular entrapment. The interstitial-fluid-to-serum ratio of apolipoprotein-B was 58% lower in T2D than in controls (0.14 vs 0.33), concomitant with increased susceptibility for LDL binding to proteoglycans. The most marked differences were seen in patients with clinically evident cardiovascular disease. The degree of transvascular retention was positively related to the propensity of isolated serum LDL to bind aortic proteoglycans, both in T2D and in controls. Skin unesterified cholesterol levels were higher in T2D patients relative to healthy controls. With aging, both proteoglycan binding and apparent vascular retention of LDL increased in controls, but not in T2D, indicating that these mechanisms may also be relevant for atherogenesis in non-diabetic individuals.
Authors
Pär Björklund, Jennifer Härdfeldt, Lauri Äikäs, Sara Straniero, Minna Holopainen, Katariina Öörni, Mats J. Rudling, Bo Angelin
Abstract
MD-PhD trainees increasingly pursue PhDs in humanities, social sciences, and public health (SSHPH). We characterized SSHPH trainee experiences and compared them to peers in traditional biomedical disciplines. From March-July 2023, a nationwide survey was sent to United States MD-PhD programs that accept SSHPH trainees. Both SSHPH and non-SSHPH trainees participated in a survey focused on belonging, challenges and barriers, funding, and leadership recommendations. Quantitative data were analyzed using Fisher’s exact tests, Student’s t-tests, and Wilcoxon rank sum tests. Qualitative comments were analyzed using a hybrid deductive-inductive approach. 234 MD-PhD trainees across the U.S. participated, with 111 (47.4%) in SSHPH and 123 (52.6%) in non-SSHPH disciplines. Overall, there were many similarities between trainees across disciplinary groups, but small and consistent differences were noted among SSHPH trainees, including decreased belonging, difficulty identifying role models, and increased work requirements during graduate school. Respondents had 5 recommendations for MD-PhD leaders and 3 recommendations for the National Institutes of Health, such as integrating SSHPH scholars into speaker series and incentivizing funding parity. Limitations include high percentages of missing responses. This exploratory study provides insights into SSHPH MD-PhD trainee experiences, highlighting similarities and unique needs that can be addressed within and across MD-PhD programs.
Authors
Cambray Smith, Evans K. Lodge, C. Ray Cheever, Seth M. Holmes, Anna R. Kahkoska
Abstract
Dedifferentiated liposarcoma (DDLS), myxofibrosarcoma (MFS), and undifferentiated pleomorphic sarcoma (UPS) are the most common types of genetically complex sarcoma. There is an urgent need to develop effective targeted therapy for these deadly sarcoma types. Despite their genetic complexity, these sarcomas share genomic alterations causing PI3K/Akt/mTOR and MAPK pathway activation, and both pathways control translation mediated by the RNA helicase eIF4A. We therefore investigated eIF4A inhibition as a therapeutic strategy. The eIF4A inhibitor CR-1-31B effectively suppressed tumor growth and induced apoptosis in DDLS, MFS, and UPS patient-derived cell lines and mouse xenografts. Transcriptome-scale ribosome footprinting identified eIF4A-dependent mRNAs such as the Hippo pathway transcriptional coactivators YAP1 (YAP) and WWTR1 (TAZ). Combined knockdown of YAP and TAZ induced apoptosis in DDLS, MFS, and UPS cell lines, and their ectopic expression partially rescued cells from apoptosis induced by CR-1-31B. Genomic analysis of patient tumors revealed that YAP and WWTR1 were frequently amplified or gained in DDLS, MFS, and UPS and were associated with worse clinical outcomes. Together, our findings identify a new strategy for targeting the Hippo pathway in incurable forms of sarcoma based on inhibition of eIF4A-dependent translation of the key oncogenic transcription factors YAP and TAZ.
Authors
Young-Mi Kim, Prathibha Mohan, Urmila Sehrawat, Evan Seffar, Rafaela Muniz De Queiroz, Kalyani Chadalavada, Nikita Persaud, Tomoyo Okada, Anirudh Kulkarni, Jianan Lin, Nathalie Lailler, Shaleigh Smith, Bhumika Jadeja, Nicholas D. Socci, Zhengqing Ouyang, Hans-Guido Wendel, Samuel Singer
Abstract
Hypoxia critically restricts the effectiveness of immunotherapy in triple-negative breast cancer (TNBC). Comprehensive bioinformatics analyses demonstrated that highly hypoxic TNBC tumors exhibited elevated T cell exhaustion, increased immune checkpoint molecule expression, and diminished responsiveness to immune checkpoint blockade (ICB). Consequently, strategies aimed at alleviating tumor hypoxia may effectively augment ICB therapy. Although ultrasound-targeted microbubble cavitation (UTMC) has been shown to reduce tumor hypoxia, the precise molecular mechanisms remain unclear. Here, we provided evidence that UTMC activated endothelial nitric oxide synthase (eNOS) through G protein–coupled signaling, resembling pathways induced by fluid shear stress. UTMC-induced eNOS activation was largely Ca²⁺-dependent and resulted in increased nitric oxide production. Enhanced nitric oxide generation was associated with improved tumor perfusion and reduced hypoxia. Combining UTMC with anti–PD-L1 therapy markedly improved the tumor immune microenvironment, characterized by increased CD8+ T cell infiltration, reduced T cell exhaustion, diminished regulatory T cell infiltration, increased macrophage polarization from an M2 to M1 phenotype, and elevated production of pro-inflammatory cytokines. Collectively, our findings identified UTMC as a promising adjunctive therapeutic approach to mitigate hypoxia and enhance the efficacy of anti–PD-L1 immunotherapy in TNBC. These results support further translational evaluation of UTMC-based combination strategies in hypoxic TNBC.
Authors
Zhiyu Zhao, Li Ba, Siwei Li, Jianxin Wang, Yuzhou Luo, Sihan Wang, Yan Jin, Changjun Wu
Abstract
Pancreatic ductal adenocarcinoma (PDAC) shows profound resistance to immunotherapy due to its immunosuppressive tumor microenvironment. Here, we studied the relationship between T cell infiltration and innate immune signaling in PDAC, identifying Toll-like receptor 2 (TLR2) as a key regulator of T cell exclusion. TLR2 expression correlated with T cell infiltration in both human and mouse PDAC tumors. Using genetic knockout models and adoptive T cell transfer experiments, we found that TLR2 expression in both T cells and non-T cells contributes to T cell exclusion in PDAC. Notably, successful infiltration of adoptively transferred tumor-specific T cells required TLR2 deletion in both the transferred cells and the recipient host. The therapeutic implications of these findings are demonstrated through both genetic deletion and pharmacological inhibition of TLR2 using AAV-mediated and antibody-based approaches in murine models, resulting in decreased tumor growth and extended survival. Collectively, these findings identify TLR2 as a key modulator of T cell trafficking and immune suppression within the PDAC microenvironment, suggesting its potential as a therapeutic target for improving treatment outcomes.
Authors
Jacqueline Plesset, Meredith L. Stone, John C. McVey, Heather Coho, Kelly Markowitz, Kayjana Coho, Jesse Lee, Anna S. Thickens, Devora Delman, Gregory L. Beatty
Abstract
HIV infection rapidly impairs the gastrointestinal (GI) barrier, contributing to persistent mucosal immune dysfunction, microbial translocation, and systemic inflammation despite antiretroviral therapy (ART). Using SIV-infected rhesus macaques on long-term ART, we investigated mechanisms underlying impairment in gut barrier-protective IL-17/IL-22 responses and the potential modulation of this pathway by dietary indoles. Longitudinal profiling of colonic epithelial and lamina propria cells revealed a selective loss of IL-17/IL-22–producing γδT cells and type 3 innate lymphoid cells (ILC3s). This loss correlated with reduced expression of the transcription factors AHR and RORγt and was associated with elevated plasma markers of intestinal epithelial barrier disruption (IEBD), including intestinal fatty acid–binding protein (iFABP), zonulin, and LPS-binding protein (LBP). Targeting this transcriptional deficiency, dietary indole supplementation for one month restored colonic AHR⁺IL-22-producing γδ T cells, RORγt⁺ ILC3s, and Vδ1 T cells, and was associated with reduced iFABP and zonulin levels. Immunohistochemical analyses further demonstrated enrichment of AHR/RORγt-co-expressing cells in the colon of indole-supplemented animals during chronic SIV infection on ART. Collectively, these findings indicate that disruption of the AHR-RORγt axis is a key pathogenic mechanism underlying persistent IEBD in chronic SIV/HIV infection. Modulation of AHR and RORγt signaling pathways in the gut may therefore represent a promising therapeutic strategy to reinforce mucosal barrier function and mitigate chronic inflammation in people living with HIV.
Authors
Siva Thirugnanam, Alison R. Van Zandt, Alexandra B. McNally, Victoria A. Hart, Isabelle Berthelot, Cecily C. Midkiff, Lara A. Doyle-Meyers, David A. Welsh, Robert V. Blair, Andrew G. MacLean, Namita Rout
Abstract
Spinocerebellar Ataxia Type 14 (SCA14) is an autosomal dominant neurodegenerative disease caused by mutations in the gene encoding protein kinase C gamma (PKCγ), a Ca2+/diacylglycerol (DG)-dependent serine/threonine kinase dominantly expressed in cerebellar Purkinje cells. These mutations impair autoinhibitory constraints to increase the basal activity of the kinase, resulting in deficits in the cerebellum that are not observed upon simple deletion of the gene, and severe ataxia. To better understand the impact of aberrant PKCγ signaling in disease pathology, we developed a knock-in murine model of the SCA14 mutation ΔF48 in PKCγ. This fully-penetrant mutation is severe in humans and is mechanistically informative as it has high basal activity but is unresponsive to agonist stimulation. Genetic, behavioral, and molecular testing revealed that ΔF48 PKCγ mice have ataxia-related phenotypes and an altered cerebellar phosphoproteome driven primarily by enhanced Ca2+/calmodulin-dependent Kinase II (CaMKII) signaling, effects that were more severe in male mice. Analysis of existing human data revealed that SCA14 has a significantly earlier age of onset for males compared with females. Data from this clinically relevant mutation suggested that enhanced basal activity of PKCγ is sufficient to cause ataxia and that treatment strategies to modulate aberrant PKCγ may be particularly beneficial in males.
Authors
Sarah A. Wolfe, Yuliang Ma, Tomer M. Yaron-Barir, Carly Chang, Caila A. Pilo, Majid Ghassemian, Amanda J. Roberts, Sang Ryeul Lee, Benjamin A. Henson, Kristen Jepsen, Jared L. Johnson, Lewis C. Cantley, Susan S. Taylor, George Gorrie, Alexandra C. Newton
Abstract
Authors
William J. Crisler, Noor Sohail, Samuel J. Steuart, Maria Vazquez-Machado, Arjun Mahajan, Maureen Whittelsey, Alex Pickering, Michael J. Martinez, Theresa Hutchins, Jessica E. Teague, Qian Zhan, Shannan Ho Sui, Ruth Ann Vleugels, Kathryn S. Torok, Heidi Jacobe, Rachael A. Clark, Avery LaChance
Abstract
Huntington’s disease (HD) is a fatal neurodegenerative disease caused by an expanded polyglutamine (CAG) repeat in the N-terminal of the Huntingtin protein (HTT). Microglial activation and elevated pro-inflammatory cytokines are observed in HD brains, but the mechanisms regulating neuroinflammation and microglial activation are poorly understood. Metformin-mediated neuroprotection has been demonstrated in experimental models of neurodegeneration, including HD. We found that metformin inhibits mitochondrial DNA (mtDNA) release and subsequent neuroinflammation in the cortex and striatum of a mouse model of HD. Moreover, elevated pro-inflammatory cytokines and microglial activation are inhibited by metformin in HD transgenic mice brain. Metformin reduced pathological microglial clusters and shifted towards a quiescent, homeostatic phenotype. Metformin improved aberrant immunometabolism in HD mouse brain and primary microglia. Mechanistically found that metformin regulates mitochondrial fission, reprograms deregulated metabolism in HD microglia, and controls microglial activation and inflammation in HD transgenic mice.
Authors
Abhishek Jauhari, Adam C. Monek, Olena S. Abakumova, Tanisha Singh, Sukhman Singh, Xiaomin Wang, Carley S. Clise, Diane L. Carlisle, Robert M. Friedlander
Abstract
The RhoBTB1-Cullin3 (CUL3) pathway in smooth muscle cells (SMCs) controls the ubiquitination and proteasomal degradation of target proteins that regulate vasodilation, vasoconstriction, and the actin cytoskeleton, and through this blood pressure (BP) and arterial stiffness. Using proximity labelling coupled with mass spectrometry in A7R5 SMCs, we identified proteins which bound to the C-terminal half of RhoBTB1 which functions as an adapter to deliver substrates to CUL3. We examined the physiological relevance of one of these substrates, RbFox2. Co-immunoprecipitation validated the interaction of RbFox2 with RhoBTB1. RbFox2 expression was elevated in response to inhibition of the ubiquitination-proteasomal pathway, CUL3-deficiency, and RhoBTB1 inhibition by either siRNA or angiotensin II (ANG). RbFox2 was ubiquitinated in a RhoBTB1- and CUL3-dependent manner suggesting its regulation through the RhoBTB1-CUL3-dependent ubiquitin-proteasome pathway. Inhibition of RbFox2 impaired the actin cytoskeleton in A7R5 cells and in primary SMC from RbFox2Flox/Flox (RbFox2F/F) mice and decreased the levels of globular and filamentous actin. ANG increased BP and arterial stiffness of RbFox2F/F mice, but the progression of arterial stiffness was halted after SMC-specific RbFox2 deletion despite a continued rise in BP. We conclude that RhoBTB1 and RbFox2 are important regulators of arterial stiffness through a mechanism that influences cytoskeletal integrity.
Authors
Gaurav Kumar, Nisita Chaihongsa, Daniel T. Brozoski, Daria Golosova, Ibrahim Vazirabad, Ko-Ting Lu, Kelsey K. Wackman, Ravi K. Singh, Curt D. Sigmund
Abstract
Authors
Anna J. Son, Emmanuel Rapp, Alex Wiezorek, Max G. Leung, Ronadip R. Banerjee, Thomas H. Leung
Abstract
VIC-1911 (formerly TAS-119) is a next-generation, ATP-competitive Aurora kinase A (AURKA) inhibitor with a favorable biosafety profile. However, it has not been evaluated in prostate cancer (PC), wherein AURKA is highly expressed in advanced stages and represents a critical therapeutic target. Here, we demonstrate that VIC-1911 potently inhibits AURKA activity with high selectivity over AURKB/C across diverse PC cell lines. Treatment with VIC-1911, even at nanomolar concentrations, substantially inhibits the growth of both androgen receptor (AR)-positive and AR-negative PC cells. VIC-1911 triggers mitotic failure, induces DNA double-strand breaks (DSBs), and activates the p53 pathway, halting cell division and inducing cell death. Notably, VIC-1911 showed synergistic effects in inhibiting PC cell growth in vitro and xenograft tumor growth in vivo with poly (ADP-ribose) polymerase inhibitors (PARPi), which have proven effective in PC with a deficiency in Homologous Recombination (HR) repair. Mechanistically, VIC-1911 disabled HR-mediated repair of DSBs in otherwise HR-proficient PC cells, leading to a “BRCAness” phenotype and pronounced accumulation of DNA damage and mitotic catastrophe. In summary, our study uncovers what we believe a novel mechanism to functional “BRCAness” by inducing mitotic arrest and highlights VIC-1911 as a promising therapeutic agent for advanced PC, either as a single agent or in combination, sensitizing HR-proficient tumors to PARP inhibitors.
Authors
Galina Gritsina, Sandip Kumar Rath, Hongshun Shi, Qi Chu, Wanqing Xie, Que Thanh Thanh Nguyen, Sambhavi Senthil, Thomas J. Myers, Mehmet A. Bilen, Sarah E. Fenton, Maha Hussain, David S. Yu, Jonathan C. Zhao, Jindan Yu
