Case Western Reserve University

NIH Research Projects · FY 2025 · 2023-08

The Systems Marketing Analysis for Research Translation (SMART) Innovation Program brings a cutting-edge set of tools together to improve clinical and translational research effectiveness, efficiency, and scale-up to improve public health and health care delivery. The SMART Innovation Program supports CTSA Program Goals by (1) developing, demonstrating, and disseminating an operational innovation that improves the efficiency and effectiveness of clinical translational, (2) a structured, participatory method for promoting partnerships and collaborations to facilitate and accelerate translational research projects local, regionally, and nationally, and (3) creating and providing this with an explicit emphasis on addressing and deliver the benefits of translational science to all. More specifically, we build on our collective prior experience and collaboration combining community based-system dynamics as a participatory method for selection and tailoring of implementation strategies with a social marketing approach within a novel set-based concurrent engineering approach from manufacturing to accelerate translational research. Our primary hypothesis is that the integration of participatory system dynamics modeling with social marketing analysis can improve clinical and translational research effectiveness, efficiency, and population health by reducing the complexity of translational research. The SMART Innovation program is designed to work with clinical researchers at any stage of the translational research continuum with an emphasis on the design of implementation strategies that maximize implementation outcomes of fidelity, reach, and sustainability of innovations that promote population health. More specifically, SMART innovation program begins with group model building to understand the context of a population health gap and innovation, identifies strategies for scaling up one or more innovations, and applies concepts from social marketing to optimize the fit between innovations and the social context. Results include a systematic approach for reducing the complexity of translational research, improved dynamic fit between innovations and local and organizational contexts, and advances in program evaluation methods for continuous quality improvement in dynamic environments.

NIH Research Projects · FY 2025 · 2023-08

Pneumonia remains the leading infectious cause of death worldwide. Ly6Chi monocytes (iMCs) have an essential role in the maintenance of homeostasis and control of pulmonary infection. While it has now been recognized that the functions of iMCs are governed by microenvironment, the impact of local cytokine milieu on iMC function remains elusive. Granulocyte-macrophage colony-stimulating factor (GM-CSF), one of the most important host cytokines that modulate the functions of iMCs, plays a critical role in host defense against several significant pulmonary pathogens; however, the precise mechanisms by which GM-CSF regulates iMC function to control pulmonary infection is still not fully understood. My recent studies have discovered that GM-CSF promotes inflammatory cytokine production by iMCs and MC-derived cells for control of L. pneumophila infection, and that GM-CSF enhances aerobic glycolysis of MCs which is required for GM-CSF-dependent inflammatory cytokine production ex vivo. The goal of this proposal is to address the critical gap in knowledge regarding the mechanisms underlying GM-CSF-mediated metabolic regulation of iMC function for control of pulmonary infection in vivo. In my preliminary studies, I observed that inhibition of aerobic glycolysis in iMCs exhibited a significant reduction of inflammatory cytokine production during in vivo L. pneumophila infection, and that inhibition of histone acetyltransferase, a key enzyme downstream of Acetyl-CoA metabolism for histone acetylation, abolished GM-CSF-dependent inflammatory cytokine production ex vivo. These preliminary findings provoke the central hypothesis that GM-CSF supports iMC function for control of pulmonary infection through aerobic glycolysis-mediated epigenetic reprogramming. My central hypothesis will be tested by 3 aims: Aim 1 will test the hypothesis that GM-CSF supports iMC functional activities to control L. pneumophila infection. Aim 2 will test the hypothesis that GM-CSF regulates aerobic glycolysis of iMCs, which is required for MC-mediated antibacterial function. Aim 3 will test the hypothesis that aerobic glycolysis supports acetyl-CoA-mediated histone acetylation, which contributes to GM-CSF regulation of MC function. Overall, this proposal will provide insight into the mechanisms underlying GM-CSF-mediated metabolic control of iMC function against bacterial pneumonia.

NIH Research Projects · FY 2025 · 2023-08

The NIH has already made substantial investments in research education programs. However, the predominant focus of the majority of NIH supported workforce development programs has narrowly focused on cultivating the next generation of doctorally prepared clinical and translational scientists with minimal attention to the need for a biomedical sciences workforce that also includes research professionals who are critical to the production of clinical and translational science (CTS). To address the need for a larger CTS workforce with varied needs, the proposed program, Intensive Summer Education Program in Translation Research for Undergraduate Students (INSPIRE- US), entails research education activities that align with the mission of the NIH and Case Western Reserve University. The proposed program, INSPIRE-US, builds on the institutional commitments of the University and the Cleveland Translational Science Collaborative, as well as the experience of the MPIs, an external advisory board, and program faculty who have led similar research education programs and understand the distinct learning and socioemotional needs of undergraduates interested in careers related to CTS. The INSPIRE-US program is conceptualized as a 10-week research education program that is tailored to the distinct needs of undergraduates interested in careers in clinical and translational science. Across the five years of this program, the program leadership aim to recruit 25 program participants. The specific aims for this application are: (1) Recruit talented undergraduates through evidence-informed strategies and collaborative institutional partnerships with colleges and universities; (2) Implement a theory-informed curriculum with complementary program activities that fosters community building and social support, hands on research experiences across the clinical and translational science continuum, didactic instruction and micro-credentialing focused on the fundamental concepts of clinical and translational science, and mentoring and career coaching activities that aim to promote persistence and the intention to pursue careers in CTS among program participants; and (3) Evaluate the short- and long-term effects of the INSPIRE-US program on participants’ career progression, program faculty, and the university. Our INSPIRE- US program leverages best practices known to promote career interest, research skill development, and the socioemotional support needed for undergraduates to successfully join the CTS workforce. If shown effective, the INSPIRE-US program is conceptualized to be reproducible and easily integrated into the activities of other Clinical Translational Science Awards (CTSA).

NIH Research Projects · FY 2025 · 2023-08

For the past 15 years, the Clinical and Translational Science Collaborative (CTSC) at Case Western Reserve University (CWRU) has integrated research efforts across five leading institutions—CWRU, Cleveland Clinic, MetroHealth System, University Hospitals of Cleveland, and the VA Northeast Ohio Healthcare System. The CTSC is now expanding its regional impact through the addition of two new partners: the University of Toledo School of Medicine and Northeast Ohio Medical University. Throughout its history, the CTSC has strengthened the quality and scope of clinical and translational science by advancing research models, technologies, and investigator training. It has supported the development of new researchers, promoted collaboration among investigators, built effective partnerships with industry and local organizations, and enabled the launch of numerous startup ventures. Looking ahead, the CTSC is launching a new initiative, the Clinical and Translational Science Collaborative of Northern Ohio: Catalyzing Linkages for Everyone’s Health (CLE Health), which will focus on expanding research engagement and enhancing the effectiveness of health interventions across various settings. Persistent variation in key health indicators, such as life expectancy, chronic disease rates, and access to care, reflects the need for more consistent integration of research into practice. Inconsistencies in recruitment and enrollment across clinical studies may limit the broader applicability and operational impact of research findings. This initiative will 1) examine and address barriers to participation in clinical research to support broader engagement; 2) enhance collaborative efforts by strengthening coordination with institutional partners and community collaborators; 3) develop and implement research programs that extend the reach and effectiveness of health interventions across a variety of clinical settings; and 4) provide practical training and education for research professionals at all career stages. To support these goals, the CTSC has established a Strategic Management Core and six key operational components: Workforce Development, Community and Stakeholder Engagement, Resources and Services, CTS Pilot Programs, Health Informatics, and CTS Research Program Support. The CTSC remains focused on practical, results-driven collaboration to improve health research and outcomes across Northern Ohio and beyond.

NIH Research Projects · FY 2025 · 2023-08

Project Summary Transfer RNA (tRNA) is best known to function in ribosome-mediated protein synthesis. However, in a less known role, arginyl-tRNA is essential for catalyzing a unique and poorly understood protein post- translational modification, namely arginylation, that regulates protein turnover. In this arginylation reaction, ATE1 (Arginyltransferase 1) facilitates arginine transfer to protein targets using a mechanism that depends on, and is selective for, arginyl-tRNA(Arg) as the donor cofactor. ATE1-mediated protein arginylation was identified on hundreds of proteins and is recognized as a global regulator of eukaryotic cellular processes, including embryogenesis, stress responses, and aging. Deregulation of ATE1 is found in patients with Parkinson’s disease and metastatic prostate, liver, and skin cancers. Nonetheless, how ATE1 (and other aminoacyl-tRNA transferases) hijacks tRNA from the highly efficient ribosomal protein synthesis pathways and catalyzes the arginylation reaction remains a mystery. This proposal aims to elucidate the catalytic mechanism and regulation of ATE1-mediated protein arginylation in vitro and in cells. We will focus on interrogating the activity of ATE1 and the consequences of arginylation at three scales. Firstly, we will determine the molecular mechanisms ATE1 selects for arginyl-tRNA(Arg) and recognizes specific sites in protein targets through an integrative approach combining structural, biochemical, and biophysical methods. Once determined, this research will allow a better understanding of the growing classes of aminoacyl-tRNA transferases in general. Secondly, we will quantitatively determine the consequences of arginylation on target protein turnover in living cells. Protein degradation usually depends on poly-ubiquitination, a downstream or concurrent event following arginylation, and through either proteasomal or autophagy-lysosomal pathways. By examining specific model substrates for proteasome or autophagosome under normal or stressed conditions, we will determine the crosstalk between arginylation and ubiquitination; delineate the contribution of each degradation pathway; reveal the kinetics in cells. Lastly, we will investigate whether and how core components of the ribosomal translation machinery and nutrients affect protein arginylation. Mechanistically, these studies will expand our knowledge of the regulatory roles of amino acids and tRNAs, enrich our toolbox to study macromolecule regulation by tRNA-dependent aminoacylation, and reshape how we consider the functions of the charged tRNAs beyond protein synthesis. Together, this research provides fundamental knowledge about arginylation, lays the groundwork for discovering novel therapeutic strategies by modulating ATE1 activity and protein arginylation in Parkinson’s disease and metastatic cancers, and enables us to build integrative platforms for future research.

NIH Research Projects · FY 2026 · 2023-08

One in eight couples are impacted by infertility, defined as difficulty obtaining or sustaining a pregnancy after one year of unprotected intercourse, and many couples turn to costly assisted reproductive technologies such as in vitro fertilization (IVF). Even with genetic screening of embryos for chromosomal abnormalities, up to 40% of embryo transfers are still unsuccessful. The lack of comprehensive mucosal systems-level data with well described implantation and both female and male fertility endpoints in the context of IVF has limited our understanding of potential microbiome, immune and intra-partner interactions that may contribute to infertility and treatment success, which has limited therapeutic options. Therefore, identifying host-microbial interactions in both female and male partners and potential intra-couple signatures of infertility could lead to novel therapeutic targets or predictive models to increase clinical pregnancy rates, which would be a significant advance. Our global hypothesis is that dysbiotic ecology and function of urogenital microbiomes drive host inflammatory processes that contribute to female and male factor infertility. In this proposal we will investigate the microbiome and immune drivers of male and female infertility by utilizing a partnered cohort with well-defined infertility and pregnancy endpoints to characterize the endometrial, cervicovaginal, seminal and penile factors contributing to IVF success. We will collect endometrial and cervicovaginal samples from the female partner during an endometrial receptivity assay (ERA) cycle which mimics the hormonal conditions present during subsequent embryo transfer cycles. A unique feature of this cohort is targeted enrollment of couples with either female or male fertility issues, providing the ability to assess fertility interactions at a per couple level. We will utilize a state-of-the-art systems biology approach including high dimensional flow cytometry with computational analysis, single cell RNA sequencing, metaproteomics, metabolomics, and host cellular analysis coupled with advanced multivariate modeling techniques to determine the effect of the female and male genital microenvironment on fertility, with the characterization female, male, and both intra- and inter- couple signatures that underlie decreased fertility. In this proposal we aim to determine the effect of the female genital microenvironment (inflammation and microbiome) on implantation success, the seminal microenvironment on semen quality and male factor infertility, and to characterize the inter-couple signatures between female and male partner microenvironment that underlie combined decreased fertility. These studies will identify host and microbial factors associated with infertility and help understand both intra-individual and inter-partner interactions that could contribute to fertility outcomes, which could identify novel therapeutic strategies or predictive models to increase clinical pregnancy rates.

NIH Research Projects · FY 2026 · 2023-08

Background. This proposal entitled “"Nuclear receptor regulation of epigenetic mechanisms regulating HIV CNS latency" is submitted in response to RFA-MH-22-280: Epigenetic Mechanisms Regulating HIV CNS Latency and Neuropathogenesis Using Novel Single Cell Technologies”. Microglial cells are the main target of HIV infection in the central nervous system (CNS) and form a reservoir of infection that persists despite antiviral treatment and contributes to HIV-associated neurocognitive disorder (HAND). Our goal. Using microglia cellular models, we demonstrated previously that the Nurr1 nuclear receptor, working in conjunction with ligand-activated nuclear receptors, plays a critical role in the regulation of HIV latency. We confirmed these observations in iPSC-derived human microglia (iMG), which provide the most informative primary cell model to study the interaction between HIV and this important target cell. Here, we will test the hypothesis that agonists of the Nurr1, RXR and RAR nuclear receptors lead to HIV silencing, suggesting a novel therapeutic strategy for HIV infections in the CNS. Underpinning this work are two key technical advances allowing the study of HIV in human microglia. First, we now have the capability to study HIV latency using iMG alone or in combination with iPSC-derived neurons and astrocytes - the first available model systems that do not rely on transformed cell lines. Second, in collaboration with the Cannon laboratory, we established a humanized mouse model of HIV latency in microglia based on the new NOG-hIL34 transgenic mouse, which is We demonstrated that the humanized mice support latent HIV infection of human microglia. We have been able to identify latently infected cells recovered from the humanized mice. In addition, we applied single cell RNA sequencing (scRNA-Seq) to confirm that the microglia have transcriptional characteristics that match reference human microglia and further identified subsets of reactive microglial cells that are associated with active HIV infections. the only humanized mouse model to support full human microglial cell maturation. Using these models, we will apply highly sensitive chromatin immunoprecipitation (ChIP) and single cell sequencing and epigenomics analyses to define nuclear receptor interactions with the HIV promoter region, and the mechanism of epigenetic silencing on the HIV LTR. How will we advance the field? Numerous clinically-effective, brain-penetrant drugs that regulate the nuclear receptors are available, many of which are now FDA approved, and will be evaluated using the iPSC derived cell models and in the humanized mouse model for their impact on HIV expression and latency in the context of an intact brain. We are undertaking these technically challenging studies because it is only by working within the context of authentic human microglial cells and an environment that better reflects the HIV-infected CNS, that the underlying physiology is accurately represented. We believe these studies will allow us to obtain a convincing proof-of-concept for this important therapeutic strategy to target HIV CNS Latency and Neuropathogenesis.

NIH Research Projects · FY 2025 · 2023-08

PROJECT SUMMARY / ABSTRACT: Glioblastoma (GBM) is a uniformly fatal brain cancer driven by a small population of self-renewing, highly tumorigenic cells termed GBM stem cells (GSCs). Our long-term goal is to find improved therapeutics for GBM by better understanding the biology that drives this disease. GBM tumors have a complex microenvironment including a relatively proliferative perivascular niche containing GSCs enriched for the stem cell marker SOX2+, and a distinct hypoxic niche that regulates resident GSCs through hypoxic signaling factors. Because the cells within distinct GBM tumor regions are remarkably different from each other, we believe that individual tumor microenvironments must be targeted with unique niche-specific therapies. However, current culture models fail to replicate the complex microenvironments of GSCs, limiting our ability to study and therapeutically target GBM. We therefore developed patient-derived GBM organoids, a controlled ex-vivo system that contains both proliferative and hypoxic niches, as well as gradients of stem and non-stem cells similar to those observed in patient tumors. We developed methods to 3-dimensionally label the separate niches of organoid cultures and used these techniques to perform the first spatially-resolved functional screen in any solid tumor. Our results pinpointed the epigenetic effector protein WDR5 as being uniquely essential to GSCs growing in the proliferative niche of GBM organoids. The objective of this application is to illuminate the roles of WDR5 in glioblastoma and determine whether disruption of WDR5 activity may have therapeutic efficacy. To achieve this, we will test the central hypothesis that GSCs require WDR5 to maintain bivalent gene expression within proliferative tumor niches, and that WDR5 can be targeted to compromise GBM growth in vivo. We will test this through execution of the following specific Aims: 1) determine if WDR5 activity is required for niche-specific GSC growth in vivo, 2) determine if WDR5 creates embryonic stem-cell-like bivalent gene regulation in GBM, and 3) determine if targeting of WDR5 function yields a therapeutic benefit in GBM preclinical models. The proposed research is an innovative first-of-its-kind study that will verify the feasibility and efficacy of niche-specific targeted screening and drug identification. This represents a significant advancement by using novel methodology and feasible new approaches to overcome an experimental barrier across many cancer types. This conceptual and experimental framework can be applied to a wide range of cancers, can unmask unique microenvironmental biology, and can allow rationally designed combination therapies against niche-specific targets. The expected outcome of this work is an understanding of the roles of WDR5 in GBM niche biology and evaluation of a novel blood-brain-barrier penetrant WDR5 inhibitor in orthotopic brain tumors. There is an urgent need to develop novel therapeutic strategies that significantly improve the survival of GBM patients. This proposal will investigate the mechanistic role of WDR5 in GBM biology, while simultaneously testing a promising potential therapeutic in highly accurate preclinical models.

NIH Research Projects · FY 2024 · 2023-08

Project Abstract: The association between decreased plasma IgG sialylation and a variety of inflammatory diseases has been known for decades. The downstream effects of changes in IgG sialylation have been studied in depth, and it is now believed that decreases in sialylation increase the affinity of IgG for activating Fc receptors, thereby driving immune activation throughout the body. Although the downstream effects of dysregulated IgG sialylation have been well documented, the regulatory mechanisms controlling IgG sialylation remain unknown. If these mechanisms are elucidated, they may serve as novel therapeutic targets to manipulate IgG function to either enhance or suppress IgG-based inflammation, depending on the circumstances. Previous research has suggested that, unlike many other glycoproteins, IgG is not sialylated efficiently during the secretory process, pointing to a B cell-extrinsic mechanism in which IgG sialylation is dynamically regulated following its release into the bloodstream. Therefore, the goals of the proposed studies are (1) to identify key regulatory mechanisms underlying IgG sialylation and (2) to elucidate how inflammatory signals are translated into changes in the IgG glycan. The success of this study will be characterized by revealing a novel and dynamic mechanism regulating IgG function through regulated changes in glycan sialylation, while providing cutting-edge scientific and professional training that blends both glycobiology and immunology to facilitate a career trajectory focused upon leadership in IgG-based therapies and translational science.

NIH Research Projects · FY 2025 · 2023-07

Project Summary Lack of effective, well-tolerated treatments for obstructive sleep apnea (OSA) has impeded research examining the impact of treatment on health outcomes, and it represents a serious lost clinical opportunity to reduce morbidity and mortality related to OSA. Metabolic modulation may be a prime target to prevent and treat OSA. One promising, newly identified pathway requiring further exploration is how pharmacologic sodium glucose co-transporter 2 inhibition (SGLT2i) may impact OSA. The overall goal of this project is to conduct a 2-center mechanistic clinical trial of N=164 overweight or obese adults (BMI 25-40 kg/m2) diagnosed with moderate to severe OSA (with and without T2D) randomized to ertugliflozin 15 mg once daily vs. placebo for 6 months to evaluate the impact of SGLT2i on anatomic, non-anatomic physiologic, and clinical traits of OSA. We will accomplish this by the following three separate specific aims: Specific Aim1: Measure the effects of SGLT2i on anatomic OSA traits. Hypothesis 1: SGLT2i will ¯ visceral and neck fat, ­ airway caliber, ¯ upper airsoft tissue structure volumes, and ¯ Pcrit/Vpass. Sub-aim 1: Explore the effects SGLT2i on plasma biomarkers of dysfunctional adiposity. Specific Aim 2: Quantify the effects of SGLT2i on non-anatomic, physiologic OSA traits. Hypothesis 2: SGLT2i will ¯ LG and ¯ rostral-caudal fluid shifts. Sub-aim 2: Explore the effects SGLT2i on ArTh and Mresp. Specific Aim 3: Investigate the effects of SGLT2i on clinical outcomes of OSA severity and sleep deficiency. Hypothesis 3: SGLT2i will improve clinical measures of OSA severity (e.g., AHI) and sleep deficiency. Sub-aim 3: Perform formal mediation analysis to assess whether the effects of SGLT2i on OSA severity and sleep deficiency clinical outcomes is mediated through individual anatomic and non-anatomic physiologic traits and markers of dysfunctional adiposity. For all aims, analyses will account for age, sex as a biological variable, race/ethnicity, obesity class, type 2 diabetes status, and CPAP use. The integrated findings of these aims will create a unique opportunity for a well powered, mechanistic trial to definitively elucidate the mechanisms of the SGLT2i-OSA relationship. This knowledge has the potential to yield new insights for pharmacologic therapeutic targets for OSA, determine which OSA patient phenotypes may be most responsive to SGLT2i, and provide preliminary data for definitive, prospective phase 3 trials to test the efficacy of pharmacologic SGLT2i on OSA prevention and treatment.

NIH Research Projects · FY 2025 · 2023-07

PROJECT SUMMARY The proposed research career development program seeks to investigate the mechanism by which myeloid cells in brain tumors become immunosuppressive, preventing the immune system from controlling the tumor even in the presence of immunotherapy designed to activate it. The candidate is currently a Research Fellow in the Department of Pathology of the Massachusetts General Hospital. The proposal incorporates specific technical skills that will be required for the project including training in immune biology and advanced immune assay techniques. The structured career development plan includes training and mentorship in laboratory management, scientific leadership, research communications, grant writing, and other critical career skills. These technical and career skills will be acquired under the guidance of Dr. Bradley Bernstein, who will serve as primary mentor and has a history of trainees that obtain group leader positions in academia, as well as a Research Advisory Committee of word-class scientists including Drs. Mario Suva, John Iafrate, and Nir Hacohen. Through this comprehensive program, the candidate will acquire a unique set of clinical and research skills that will enable him to transition to an independent physician scientist faculty position with a lab focused on basic mechanisms and therapeutic opportunities in brain cancer epigenetics and immunology. The research strategy will investigate immunosuppressive tumor-associated myeloid cells in brain tumors – where they come from, the epigenetic mechanism by which they become immunosuppressive, and how to potentially transform them. Transforming or selectively killing myeloid cells that express immunosuppressive programs offers great opportunity to sensitize brain tumors to immunotherapy. However, it remains unknown if these myeloid cells come from circulating monocytes or endogenous microglia, or what make them immunosuppressive, significantly hindering the design of rational clinical strategies to target these cells in brain tumors. The aims of this proposal are to: (1) Determine the origin of immunosuppressive myeloid cell states in brain tumors, (2) identify the epigenetic regulatory factors that maintain the immunosuppressive cell program, (3) discover perturbations that eliminate or transform immunosuppressive myeloid cells. Overall, these studies will provide valuable data needed to develop targeted therapies against immunosuppressive myeloid cells and increase the efficacy of immunotherapy for brain cancer patients.

NIH Research Projects · FY 2024 · 2023-07

Eph receptors make guidance decisions for cell migration in cardiovascular and neuronal development, disease, and regeneration. Eph receptors are also involved with higher brain functions, memory and learning. A protein that has been associated with Alzheimer’s, Parkinson’s and other neuronal diseases and injuries is the Collapsin Response Mediator Protein (CRMP) which interacts with several kinases and becomes hyper-phosphorylated alongside increased activation of the kinases. The hyper- phosphorylated CRMP then disrupts the formation of actin and microtubule cytoskeletal structures and it thought to impede Aβ and tau clearance. Cytosolic Lyn kinase, a close homologue of Fyn kinase, is known to interact directly with EphA4 and here, for the first time, we show that an EphA family member and EphB2 directly interacts with CRMP. Analogous to another guidance and cell migration system, the Fyn-Plexin-CRMP complex, the Lyn-EphA4-CRMP association is likely to form a complex with Cdk5 and GSK3β kinases, each also involved in Alzheimer’s. The features of the Eph-CRMP and Eph-Lyn interacting interfaces need to be characterized, as they will be potential biomarkers and targets for therapeutic intervention. The proposal has two main aims. Aim 1) seeks to establish the in vitro phosphorylation patters of various kinases on the intracellular domains of EphA4 and –B2 in the presence and absence of CRMP and to further validate the formation of the complex in cells. Aim 2) The effect that the corresponding phosphomimetic/phospho-defective mutations have on the level of activity on these Eph receptor intracellular regions and of the kinases will be studied with purified proteins in vitro. Eventually, using the knowledge from this project, Antibodies or complex-disrupting-peptides may drive the future development of early detection diagnostics and/or therapeutics.

NIH Research Projects · FY 2025 · 2023-07

Project Summary/Abstract There is strong national consensus about the need to deliver high-quality care at the end of life (EOL) for patients with advanced (distant metastasis) cancer. Yet, despite the efforts of healthcare providers, many patients receive care that they do not want at EOL and leave their informal caregivers struggling with complicated grief months after their death. Research, to date, has tended to define quality EOL care using unidimensional factors that do not encompass key aspects of EOL care, such as patient and family-centered EOL care that holds individual preferences for EOL care at its core. Specifically, quality EOL care has been defined in terms of either: (a) amount of aggressive health care services received, or (b) whether it was “goal concordant care”---care that aligned with the patient’s preferences and goals for EOL care. These approaches have provided limited perspectives of what constitutes quality EOL care. Aggressiveness metrics (e.g., days of hospitalization, number of emergency department visits), for example, ignore the fact that some patients want aggressive care at EOL and goal concordant care metrics ignore the post-death QOL of caregivers. It is usually the patient-caregiver dyad who experience the trajectory of care, and who need support throughout. With patients continuing to receive EOL care that they do not want and caregivers struggling with poor post- death outcomes such as complicated grief, we need a new paradigm for conceptualizing quality EOL care. This project will be the first to apply the principles of a dyadic theory of illness to examine the relationships between patient-caregiver dyadic factors (e.g., dyadic incongruence for patient symptom severity) and dyadic quality EOL care. We have reconceptualized quality EOL care to be care that benefits both members of the dyad and is present when the patient identifies the receipt of goal concordant care at EOL and the caregiver does not demonstrate complicated grief 3 months post-death. This longitudinal, descriptive, correlational study will address the following aims: Aim 1: Examine the influence of dyadic appraisal of illness factors upon dyadic quality EOL care (present or absent); Aim 2: Examine the influence of risk-protective contextual factors (individual, dyadic, family/social) on dyadic appraisal of illness factors (symptoms, EOL treatment preferences, EOL values) over time; and Aim 3: Assess the extent to which dyadic appraisal of illness factors mediate the relationship between risk-protective contextual factors and dyadic quality EOL care. Identifying specific dyadic variables (such as symptom severity incongruence) that relate to dyadic outcomes can facilitate the development of dyadic interventions aimed at enhancing communication or knowledge, for example, for both members of the dyad over time. By enhancing dyadic outcomes, we will have better stewardship of healthcare resources for patients at EOL and ensure improved quality EOL care for patients and improved post-death outcomes for caregivers---those who must carry on after the patient’s death.

NIH Research Projects · FY 2024 · 2023-07

With the increase in life expectancy of people living with HIV (PLWH), principally due to the introduction of antiretroviral therapy (ART), it has become evident that these individuals differentially acquire a wide range of health problems, including oral health complications, which severely impact quality of life and incur substantial healthcare costs. We previously identified an altered proteomic profile of human oral keratinocytes isolated from PLWH patients, suggesting elevated cellular stress and reduced ability to provide robust innate immune protection. We also demonstrated that these epithelial cells display altered epigenetic markers, reduced proliferative capacity and respond weakly to microbial challenges. We now hypothesize that in PLWH, oral epithelial cell dysfunction predisposes towards susceptibility to secondary viral infections, such as HPV. We have assembled an interdisciplinary team of experts whose expertise encompasses HIV and HPV virology, oral and epithelial cell biology, epigenomics and bioinformatics. We propose to apply a novel non-invasive method of collecting oral mucosal cells from PLWH and conduct genomic and epigenomic analyses of the oral epithelium (Aim 1). Additionally, using a relevant HPV infection model, we wish to determine if such cells expanded from the oral mucosa of PLWH, which we have demonstrated exhibit an altered proteome, are more susceptible to HPV infection when compared to oral epithelial cells from healthy controls (Aim 2). These studies will be the first to establish the transcriptomic and epigenomic effects of HIV infection on primary epithelial cells, establish a new culture-based assay system so critical for future mechanistic and therapeutic studies, and enable direct comparisons between these in vivo and in vitro methods to robustly identify key molecular features that are central to the increased HPV susceptibility seen in PLWH. Successful completion of the goals of this R21 will enable targeted hypothesis-based genomic or epigenomic studies (i.e. shRNAs, CRISPR, or small molecules) to identify specific genes/pathways mediating the HPV susceptibility, and functionally test HPV infection levels. Validating the epigenetic basis of susceptibility to HPV infection in PLWH will eventually guide the discovery and application of novel epigenomic-based clinical interventions; all consistent with the goals of the NOSI NOT-DE-21-019 “Basic and translational oral health research related to HIV/AIDS.”

NIH Research Projects · FY 2026 · 2023-07

Project Summary/Abstract There is a critical need to translate retinal ganglion cell (RGC) therapies from lab to clinic, particularly cell transplant therapies to repair degenerated eye tissues and restore visual function. RGC transplant has great potential in treating degenerative retinal and optic nerve diseases, but key pre-clinical studies are hampered by an inability to track transplanted cells. In this project, the candidate proposes to advance RGC transplant in treating glaucoma through longitudinal and non-invasive tracking of RGCs with the aid of nanoparticle-based optical coherence tomography (OCT) contrast agents. These nanoparticles are to be customized to label and visualize RGCs with a high spatial resolution. Longitudinal tracking of the RGCs in vivo could uncover the fate of the donor RGCs, increase our understanding of their behavior in the eye, and identify the factors that affect the treatment efficacy of RGC transplants. In this application, the PI first proposes to use spectral OCT signals of gold nanorods (GNRs) to maximize the contrast between donor RGCs and the retina in OCT imaging. Second, the PI proposes to examine the correlation between the OCT signals of GNRs and the fate of donor RGCs with both in vitro and in vivo assays. Third, the PI proposes to test the effects of cell number and injection location on the transplant success rate, and to leverage advanced imaging to optimize RGC transplantation. Overall, investigations in GNR-based OCT contrast agents for in vivo RGC tracking will gain us essential knowledge in the efficacy of RGC transplant and advance RGC transplant for glaucoma treatment. These data will contribute to the PI’s overall career goals, to investigate biomaterials that could track, support, and control therapeutic cells in vivo and to use these biomaterials to provide novel methods to treat otherwise incurable diseases. During the mentored phase of this award, the candidate will prioritize undertaking activities to increase understanding and gain hands-on training in the areas of OCT and glaucoma in the Department of Ophthalmology at Stanford, with support from the world-class Molecular Imaging Program and the outstanding Materials Science & Engineering Community at Stanford, and with the benefits of a close-knit and focused department and the multi- interdisciplinary collaborations and resources of the more comprehensive university.

NIH Research Projects · FY 2025 · 2023-07

PROJECT SUMMARY/ABSTRACT A resurgence of research interest in bacteriophages, viruses that infect bacteria, is driving the development of engineered phages for biomedical applications, including antimicrobial therapy and phage-based vaccination. As antimicrobial agents, phages have significant advantages over conventional antibiotics: they are well- tolerated, pathogen-specific, and replicate at the site of infection. Phages are also promising as vaccine platforms because they can be precisely engineered to deliver multiple foreign antigens. However, phages are immunogenic and both applications are susceptible to interfering immune responses. Antimicrobial phages, for example, can elicit neutralizing antibodies that prevent infection of the bacterial target. This immunogenic nature is advantageous for vaccine development, since the phage acts as its own adjuvant, but it comes at a price: off-target responses to immunodominant phage antigens can distract from intended protective responses to foreign antigens. Unfortunately, data on phage immunology are limited, confounding routine biomedical applications of phage. This proposal outlines basic experiments to elucidate the basis of phage immunogenicity and evaluate methods of modulating it. Aim 1 will develop a structural map of antibody binding to three therapeutic mycobacteriophages. Structure- guided engineering and directed evolution will be used to generate mutant phages that escape antibody binding. The ability of these mutants to evade established immune responses to their wild-type counterparts in vivo will be evaluated in a mouse model. In Aim 2 the same phages will be used as platforms for a therapeutic bacterial vaccine. Leveraging both phage display and phage DNA vector technologies, the vaccine candidates will defend and protect against bacteria with three mechanisms: 1) phage infection and killing, 2) generation of bacterium-binding antibodies, and 3) activation of helper and cytotoxic T cells. Aim 3 will evaluate a method to suppress interfering immune responses: co-administration of phage with rapamycin-loaded nanoparticles. This will down-regulate phage-specific helper T cells and upregulate regulatory T cells, training the immune system to recognize phage as ‘self’. These Aims will expand our understanding of phage immunogenicity and assess the potential to improve phage-based medicine with principles from immunoengineering. Furthermore, Aim 1 is a training vehicle for the candidate, who has developed immunology experience in the lab but requires mentored training and formal education to establish independence in this field. Aim 1 also provides additional mentored training in structural biology, specifically asymmetric reconstructions of phage-antibody complexes. With the planned scientific training, practice in publishing and grant writing, and the support of her mentors throughout an academic job search, the candidate is expected to establish and sustain an independent research career focused on immunoengineering phage to improve their biomedical applications.

NIH Research Projects · FY 2025 · 2023-07

PROJECT SUMMARY/ABSTRACT Ewing sarcoma is a highly aggressive bone and soft tissue tumor mainly affecting children and young adults, which still lacks effective therapy. Due to its low mutational burden, there are very few acquired vulnerabilities in Ewing sarcoma cells. During my postdoctoral work, I discovered that transcription factor ETV6 is among the very few top Ewing sarcoma-biased dependencies. Remarkably, although ubiquitously expressed, ETV6 is not essential for cancer cells outside Ewing sarcoma, based on CRISPR screening efforts from us and others. Genetic studies in mice also revealed that ETV6 is dispensable in the majority of tissues. Hence, perturbing ETV6 function in Ewing sarcoma will have a wide therapeutic index. In the proposed project, I aim to further study the detailed mechanisms of how ETV6 maintains the cancer cell state, and leverage this new knowledge to develop therapies for Ewing sarcoma patients with exceptional potency and specificity. To do so, I will characterize the mesenchymal differentiation phenotype of ETV6-deficient Ewing sarcoma cells using high- throughput functional genomics and single cell transcriptomics. Integration of these `-omic' approaches allow me to obtain a deep biochemical understanding of the cancer maintenance function of ETV6 (Aim 1). Moreover, I showed that expression of the Sterile Alpha Motif (SAM) domain of ETV6, which is responsible for its self- oligomerization, has a dominant-negative effect to endogenous ETV6, and inhibits sarcomagenesis in vivo. Therefore, I propose to optimize this SAM peptide to increase its potency and further engineer it for exogenous delivery (Aim 2). Successful generation of a potent, and tumor penetrating ETV6 blocker will benefit therapy development. Finally, as transcription factors, like ETV6, have proven to be challenging targets for drug development, I profiled for endogenous metabolites that can bind ETV6 to unveil druggable pockets, and identified its association with phosphatidic acid. I will further explore the regulatory effects of phosphatidic acid binding to ETV6 in Ewing sarcoma (Aim 3). Results from these studies will guide small molecule development, and more importantly, will also reflect a novel mechanism for metabolic control of gene expression through direct allosteric regulation of transcription factors. During the mentored K99 phase, I will work closely with my mentor Dr. Christopher Vakoc and co-mentor Dr. Carolyn Fein Levy, and collaborators Drs. Stegmaier, Kentsis, Shi and Furukawa, recognized experts in pediatric oncology, peptide therapy, screening methodology and structural biology respectively. I have also established an exceptional advisory committee at CSHL, constituted by Drs. Joshua-Tor and Beyaz, who will monitor and support my transition to independence. In addition, CSHL will provide me an outstanding scientific environment for my research and training, being a conference hub for world-renowned meetings and courses. My objective is to obtain a faculty position to develop an impactful research program, where the K99/R00 funding mechanism will serve as an essential step in my transition to independence.

NIH Research Projects · FY 2025 · 2023-06

PROJECT SUMMARY: Cancer immunotherapy is based on the premise of immune-recognition and targeted killing of tumor cells, thus possesses the promising power to eradicate aggressive disease. Notably to date, immunotherapy with immune checkpoint inhibitors significantly prolongs the survival of patients. Unfortunately, recurrent and metastatic disease occurs to a significant portion of patients within 5 years largely due to resistance to the immune checkpoint inhibitor. This largely stems from the local immunosuppressive tumor microenvironment (TME), which is enriched with immunosuppressive myeloid cells. To reprogram the TME into a “hot” environment enriched with functional myeloid cells, we designed a dual action immunostimulatory nanoparticle (dual-NP) that triggers a highly potent activation of the dysfunctional tumor-resident myeloid cells. The premise of our strategy is based on three key components: (1) Our previous studies showed that V domain Immunoglobulin Suppressor of T cell Activation (VISTA) is a novel myeloid cell-intrinsic immune checkpoint protein, which controls antitumor immunity. We showed VISTA is highly expressed on immunosuppressive myeloid cells and blocking VISTA can synergize with TLR9 agonist to reprogram the immunosuppressive myeloid cells to boost antitumor immunity. (2) The dual-NP is co-loaded with a VISTA siRNA and the TLR9 agonist CpG. Upon intratumoral administration, the dual-NP ensures the simultaneous uptake of its synergistic cargoes by the same tumor-resident myeloid cells and proficient intracellular delivery of each cargo, thus achieving optimal effects to activate these cells. Our recent studies show that simultaneous silencing of the VISTA gene and stimulation of TLR9 leads to a synergistic T cell-mediated tumor clearance and curative responses with protective immunological memory against tumor recurrence. (3) We developed a simple and controllable method to generate ionizable lipid dual-NPs of different sizes (i.e., 30, 40 or 60 nm) with high degree of uniformity and consistency. Our studies show that small dual-NPs achieve widespread distribution and predominant uptake by myeloid cells throughout the tumor volume upon intratumoral administration. Innovation: To our knowledge, this is the first effort to combine advanced nanoparticle design, simultaneous delivery of siRNA and a TLR agonist, and silencing of a gene related to an immune checkpoint protein specific to myeloid cells. AIM 1: Optimize the design of the dual-NP and test the ex vivo and in vivo efficacy in reprograming tumorassociated myeloid cells. AIM 2: Evaluate the short and long-term safety profile of the dual-NP and characterize the mechanism of antitumor immune responses associated with dosage and frequency of dual-NP administration. AIM 3: Evaluate the therapeutic efficacy of the dual-NP as a monotherapy and in combination with standard immune checkpoint inhibitors in murine models of advanced melanoma and metastatic breast cancer.

NIH Research Projects · FY 2025 · 2023-06

Abstract Breast cancer (BC) is the most diagnosed cancer and the second leading cause of cancer death in American women. Triple negative breast cancer (TNBC) accounts for 15% to 20% of all BC cases and has the worst prognosis and overall survival. Although many targeted agents are ongoing clinical trials, none have significantly improved the survival in TNBC patients. Thus, the identification of novel targets and effective strategies, including combination therapies, are urgent needed for TNBC patients. PRMT5 is emerging as a potential therapeutic target. Several PRMT5 inhibitors have been developed and are currently being evaluated in clinical trials, including a phase II trial for early-stage BC. Compared to other BC subtypes, TNBC displays the strongest PRMT5 expression. High PRMT5 expression is positively correlated with poorer survival rate in TNBC patients. Despite its association with TNBC progression, PRMT5 regulation and the molecular mechanisms by which PRMT5 promotes TNBC remain elusive. Moreover, TNBC cell lines display differential sensitivity or resistance to PRMT5 inhibitors, but the mechanisms have yet to be defined. Our preliminary studies demonstrate that: (1) PRMT5 is ubiquitinated by E3 ubiquitin ligase TRAF6, which is important for its activation and TNBC cell proliferation; (2) PRMT5 suppresses autophagy induction and catalyzes ULK1 arginine methylation; and (3) autophagy inhibition sensitizes TNBC cells to PRMT5 inhibitor. Based on these preliminary findings, we propose three aims to test our central hypothesis that TRAF6, PRMT5, and ULK1 form a novel axis to regulate autophagy and TNBC progression, and combination of PRMT5 and autophagy inhibitors is a potential strategy to combat TNBC. To validate our hypothesis, we propose three Aims. In Aim 1, we will define the mechanism through which TRAF6 regulates PRMT5 activation. In Aim 2, we will define the molecular function of PRMT5 in autophagy regulation by methylating ULK1. In Aim 3, we will evaluate the synergistic effect of PRMT5 and autophagy inhibitors in TNBC. We believe that our proposed studies will not only substantially advance current understanding of regulatory mechanism and biological function of PRMT5, but also provide a rationale for combination of PRMT5 and autophagy inhibitors to treat TNBC.

NIH Research Projects · FY 2026 · 2023-06

PROJECT SUMMARY Debaryomyces hansenii is a fungal member of the gut microbiome and is present within inflamed regions of the intestine in Crohn Disease patients. Patient-derived strains of D. hansenii prolong wound healing in mouse chemical and mechanical intestinal injury models. Mechanisms of pathogenicity of D. hansenii are not well understood, though macrophages are a key effector cell type in the delayed wound healing phenotype. The objective of the proposed work is to define mechanisms of innate host response to D. hansenii using in vitro macrophage models and define microbial mechanisms of impaired wound repair using in vivo models of intestinal injury. Our preliminary data visualizing phagocytosed D. hansenii with transmission electron microscopy and cytological staining demonstrate certain macrophages phagocytose and are unable to clear D. hansenii. Macrophages that do not clear D. hansenii also do not produce TNF-α in response to D. hansenii. In aim 1, I test the hypothesis that TNF-α supports macrophages clearance of phagocytosed D. hansenii and identify the pattern recognition receptors responsible for TNF-α production. In aim 2, I examine microbial morphologic-transitions as an immune evasion mechanism in vitro and in vivo. My preliminary data suggest that vegetative D. hansenii yeast induce more potent pro-inflammatory cytokine production than spores of D. hansenii, and spores persist within macrophage cell lines in vitro. This project will define microbial mechanisms that permit D. hansenii persistence within the intestine and antagonism of injury repair. Successful completion of these aims will define mechanisms of host-response to D. hansenii and microbial-evasion of macrophage clearance that will lead the identification of novel therapeutic targets for treating the subset of Crohn Disease patients with tissue associated D. hansenii.

NIH Research Projects · FY 2025 · 2023-06

PROJECT SUMMARY Walking over natural terrain with skill and flexibility requires the nervous system to adapt limb movements to environmental demands on each step. To drive the limbs over an obstacle without stumbling, the brain must generate commands to modulate the appropriate muscle synergies at a specific phase of the ongoing locomotor rhythm. The loss or impairment of these commands in disease can result in falls, which are common in older adults and impose a significant burden on the healthcare system. While previous studies have demonstrated that the motor cortex is critical for skilled locomotion, two key gaps currently impede progress in developing models of cortical control. First, because gait modification is controlled by coordinated patterns of activity across the motor cortical population, it is necessary to measure these population-level patterns in behaving animals, and to identify how these patterns relate to specific aspects of movement. Second, because motor cortex generates descending commands by integrating multiple sources of input from other brain regions, it is critical to determine how these inputs influence motor cortical dynamics along specific, behaviorally-relevant dimensions. Our long-term goal is to identify the dynamical principles governing the interactions across distributed neural populations, and to determine how these principles enable the adaptation of the locomotor pattern in a complex environment. The overall objective of this proposal is to determine how neural population dynamics in motor cortex are generated during skilled locomotion by identifying the impact of cerebellar and posterior parietal inputs on specific motor cortical dimensions. Our central hypothesis is that the cerebellum selectively drives step-entrained dimensions of motor cortical population activity that are synchronized with the rhythm of lower motor centers, while the posterior parietal cortex selectively drives motor commands for gait modification in obstacle-modulated dimensions. To directly test this hypothesis, we will first record from motor cortical ensembles in unrestrained mice performing skilled locomotion and use computational techniques to isolate step-entrained and obstacle-modulated dimensions of neural population activity (Aim 1). Next, we will use optogenetic perturbations to identify the effect of disrupting inputs from the cerebellum (Aim 2) and posterior parietal cortex (Aim 3) on activity in these dimensions. The proposed research is significant because the identification of how inputs to motor cortex generate its dynamics in healthy animals is expected to provide a foundation for future studies of how these dynamics degrade in neurodegenerative disease and aging, and to support the improvement of closed-loop deep brain stimulation strategies for movement disorders. The proposed research is innovative because it integrates the dynamical systems framework for the analysis and interpretation of data with the optogenetic toolkit for neural circuit perturbations, enabling a transition beyond the measurement of cortical population trajectories toward a definition of the underlying dynamical principles that generate them.

NIH Research Projects · FY 2026 · 2023-06

Project Description Loss of function of gamma-aminobutyric acid type A (GABAA) receptors is one prominent cause of genetic epilepsies since they are the primary inhibitory ion channels to maintain the excitation-inhibition balance in the mammalian central nervous system. Currently, hundreds of clinical variants have been identified in GABAA receptor subunits, causing their functional defects. Despite the development of numerous anti-seizure drugs, about one-third of epilepsy patients are resistant to current drug treatment, and many of them have genetic causes. Therefore, there is an urgent need to understand the molecular mechanism for the loss of function of pathogenic GABAA receptors as well as to develop a new therapeutic strategy to correct their function. It has been recognized that reduced surface trafficking of GABAA receptor variants is one major molecular mechanism for their loss of function. To reach the plasma membrane to carry out their function, GABAA receptor subunits need to fold and assemble into pentameric receptors in the endoplasmic reticulum (ER). Many epilepsy-causing GABAA receptor variants predispose them to protein misfolding in the ER and thus excessive protein degradation. Recently, we showed that we can correct the function of such variants by restoring their trafficking to the plasma membrane. Therefore, the overall objective of this proposal is to understand how cellular degradation pathways remove misfolding-prone GABAA receptor variants; furthermore, we hypothesize that we can correct the folding of these pathogenic variants to enhance their surface trafficking and thus function, as a novel strategy to treat genetic epilepsies. Here, in Specific Aim 1, we will characterize the cellular degradation pathways that remove misfolding-prone GABAA receptor clinical variants. In Specific Aim 2, we will elucidate a coordinated folding pathway that directs the protein folding of GABAA receptors in the ER. In Specific Aim 3, we will use small molecules to correct the folding and thus function of misfolding-prone GABAA receptor clinical variants.

NIH Research Projects · FY 2025 · 2023-06

PROJECT SUMMARY/ABSTRACT Studying genetic contributions to dementia risk from both the population-specific and trans-ancestral perspectives is vital to disease prediction, characterization, and the development of treatment interventions. Late-onset Alzheimer’s disease (LOAD) is the most common form of dementia, costs the United States an estimated $305 billion in associated costs, and affects approximately 6 million individuals nationally, and more than 24 million people globally. Apolipoprotein E (ApoE) is the strongest known genetic risk factor for LOAD. Specifically, ApoE-associated LOAD risk is driven by a risk variant of ApoE (termed ε4 or ApoE4) while ApoE- associated LOAD protection is thought to be driven by a protective variant of the gene (termed ε2 or ApoE2). The allele frequency of these alleles varies across populations, partially explaining higher LOAD prevalence in populations of African descent who carry the highest ApoE4 allele frequencies. In contrast to these findings, evidence indicates ApoE4-associated LOAD risk is significantly lower in individuals of African descent compared to other groups. This effect modification is partially driven by population-specific local ancestry that modifies the effect size of ApoE4. This observation, however, does not fully explain the reduction in effect size in African Americans. I hypothesize that genetic variants (local and global) modify ApoE4 and ApoE2 effect sizes. This proposal describes three aims to address the investigation into genetic contributions to ApoE- associated LOAD risk in multiple, diverse populations. Aim 1 will document the relationship between LOAD risk and the ApoE4 and ApoE2 alleles in the largest and most diverse dataset to be studied to date by estimating effect sizes in each of several diverse populations. Aim 2 will identify SNPs that associate with extreme ApoE4 and ApoE2 effect sizes and test whether these SNPs define specific physiological pathway association. Finally, aim 3 will evaluate the relative roles of race/ethnicity and genetic variation as modifiers of effect sizes within and between populations. As an MD/PhD candidate, I am passionate about this project as it will lead to new insights that can be used to understand, identify, and predict LOAD risk in underserved populations in the United States, especially those that experience increased LOAD burdens. The combined educational support from the Population and Quantitative Health Sciences Department and clinical training from the Medical Scientist Training Program at Case Western Reserve University will prepare me in tackling the genetic and healthcare avenues this work aims to inform. With support from these sources, and committee members with expertise in population genetics, statistical analysis, and bioinformatics, my training will provide the skills necessary to become a physician scientist versed in rigorous statistical approaches to understanding contributions to complex diseases.

NIH Research Projects · FY 2025 · 2023-06

Project Summary/Abstract Postoperative atrial fibrillation (POAF) is the most common complication following open heart surgery, with an incidence of up to 50%. It is associated with significant morbidity, including stroke, heart failure, and hemodynamic compromise. For the treatment of POAF, there are two strategies, either rhythm control (restoring and maintaining sinus rhythm) or rate control (controlling ventricular rate). Medications used to maintain sinus rhythm are largely ineffective, and those used to control ventricular rates during POAF often cause hypotension. Therefore, to improve management of POAF, a non-pharmacologic treatment strategy could be implemented. The current non-pharmacologic treatment of POAF is direct current (DC) cardioversion, which is often needed to treat patients who are hemodynamically unstable. However, DC cardioversion is often ineffective, as the POAF usually returns quickly. Although a recent clinical trial showed that rhythm control and rate control are equivalent in terms of mortality, length of hospital stay, and complication rates, a longer duration of POAF is associated with worsened long-term survival and risk of AF recurrence. The lack of satisfactory treatment of POAF is due in large part to our insufficient understanding of its mechanism. In our canine sterile pericarditis model (an experimental counterpart to POAF), we demonstrated that activation and proliferation of epicardial inflammation occurring in the atria produces a loss of epicardial myocytes and an altered distribution of connexins 40 and 43. These changes are associated with non-uniform slowing of conduction, thus creating the vulnerable substrate for the spontaneous initiation and maintenance of POAF. Our epicardial mapping studies in this model demonstrated that POAF is caused by a reentrant circuit circulating around pulmonary veins. Our recent study in patients with POAF after open heart surgery showed that atrial electrograms during POAF recorded from selected left atrial (LA) sites demonstrated regular cycle lengths, consistent with a LA reentrant circuit similar to our canine model. Therefore, like other reentrant arrhythmias, the POAF rhythm has the potential to be pace terminated (rhythm control). When there is another mechanism maintaining POAF, a rate control approach using fat pad stimulation could be used to control the ventricular rate during POAF. The central hypothesis of our proposal is that when POAF is due to a reentrant mechanism, it can be terminated by a non-pharmacologic rhythm control strategy (overdrive pacing); when POAF is due to other mechanisms, it can be managed by a non-pharmacologic rate control approach (atrioventricular node fat pad stimulation). The hypothesis to be tested has three specific aims: Aim 1 is to develop non-pharmacologic approaches in our canine model. Aim 2 is to test the hypothesis that POAF is due to an anatomical reentrant circuit in patients after open heart surgery. Using entrainment pacing during POAF, we will verify the existence of a reentrant circuit. Aim 3 is to test the hypothesis that POAF can be managed by a patient-specific non-pharmacologic approach. Insights from our proposed studies will change the paradigm for the treatment of POAF, and contribute to improved clinical outcomes in these patients.

NIH Research Projects · FY 2026 · 2023-05

Project Summary The aggressiveness of triple negative breast cancers (TNBCs) is, in part, due to their metastatic behavior, propensity to recur rapidly and dismal low response to standard-of-care chemotherapies. TNBCs are associated with the worst prognosis and clinical outcomes, especially in African American (AA) women. Interestingly, the incidence rate of TNBC is more than 2-fold higher in AA women, compared with their Caucasian American (CA) counterparts who have the same disease. These racial-associated disparities in outcomes, that remain poorly understood, are significant even after controlling treatment variations, and suggest the contribution of differences in tumor biology to these disparities in cancer outcomes. We identified YB1, a multifunctional gene, as a potential biological driver of TNBC disparities in AA women. We also found that the oncogenic signaling of YB1 may play a major role in activating the invasion-metastasis cascade and therapy resistance of TNBC in AA women. YB1 expression levels are significantly higher in AA tumors and are strongly associated with poorer overall survival in AA TNBC patients. YB1 nuclear localization/phosphorylation (S102) is also correlated with cancer stem cell phenotype, and resistance to chemotherapy in TNBC tumors of AA origin. Based on this strong evidence, we developed the overarching hypothesis that YB1 oncogenic signaling is a major contributing factor to differences in disease outcomes between AA and CA TNBC patients. This hypothesis will be addressed by investigating the biologic and clinical significance of YB1 signaling axis in TNBC disparities. Our proposal will also attempt to better elucidate the complex interactions between genetics, environment and lifestyle that may contribute to the observed differences with the ultimate goal of developing and implementing more efficacious population-based strategies to improve health for this vulnerable population. Our specific aims will (1) Determine the impact of YB1 signaling (expression, phosphorylation and nuclear localization) in tumorigenicity and chemoresistance in TNBC cell lines and tumors of AA origin; (2) Determine the impact of novel combination therapies targeting YB1 to alleviate progression and metastasis of AA TNBC tumors; and (3) Determine whether YB1 signaling can predict racial disparities and chemoresistance in TNBC, based on transcriptomics and immunohistochemistry. We are very confident that our innovative proposal will make great contributions to the field of cancer disparities, especially for AA women with TNBC, and will identify new YB1-based therapeutic options for this devastating cancer that is disparately affecting AA women.