Selected Grantee Publications
Integrative Multi-omics Analysis Uncovers Tumor-Immune-Gut Axis Influencing Immunotherapy Outcomes in Ovarian Cancer
Rosario et al., Nature Communications. 2024.
https://pubmed.ncbi.nlm.nih.gov/39638782
Recurrent ovarian cancer (OC) is the deadliest gynecological malignancy, with a 5-year survival rate of 50% and a median progression-free survival (PFS) of 1.9 to 2.1 months. A trial cohort of 40 patients was treated with a combination of the anti-PD-1 pembrolizumab, the anti–vascular endothelial growth factor bevacizumab, and cyclophosphamide. The investigators conducted a multi-omics analysis—including transcriptomic analysis, digital spatial profiling, 16s-rRNA sequencing, and metabolomics—to understand the underlying mechanisms for the enhanced PFS to a median of 10.2 months and overall response rate of 47.5%. Multi-omics analysis highlighted the formation of tertiary lymphoid structures known to improve responses to immunotherapy, differential microbial patterns, and alterations in the metabolites in three key metabolism pathways that enhanced immune response in patients to produce a durable clinical response. These findings highlight the importance of the tumor microenvironment and the gut microbiome, along with its metabolites, in elevating the efficacy of the cocktail therapy in recurrent OC patients, thereby enhancing their survival and quality of life. Supported by ORIP (S10OD024973) and NCI.
A Switch from Glial to Neuronal Gene Expression Alterations in the Spinal Cord of SIV-Infected Macaques on Antiretroviral Therapy
Mulka et al., Journal of Neuroimmune Pharmacology. 2024.
https://pubmed.ncbi.nlm.nih.gov/38862787/
Up to one-third of patients with HIV experience HIV-associated peripheral neuropathy, affecting sensory pathways in the spinal cord. Spinal cord sampling is limited in people with HIV. Researchers examined gene expression alterations in the spinal cords of simian immunodeficiency virus (SIV)-infected male pigtail macaques with and without antiretroviral therapy (ART), using RNA sequencing at key time points throughout infection. Results indicate a shift from glial cell-associated pathways to neuronal pathways in SIV-infected animals receiving ART. These findings suggest that neurons, rather than glia, are predominantly involved in ART-related neurotoxicity and offer new insights into therapeutic strategies for maintaining synaptic homeostasis. Supported by ORIP (U42OD013117, T32OD011089) and NINDS.
Aberrant Activation of Wound-Healing Programs within the Metastatic Niche Facilitates Lung Colonization by Osteosarcoma Cells
Reinecke et al., Clinical Cancer Research. 2024.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11739783/
The leading cause of deaths in the pediatric osteosarcoma is due to lung metastasis. A current clinical need is the development of therapies that disrupt the later stages of metastasis. Researchers used 6- to 8-week-old female C57BL/6 and CB17-SCID mice to understand how tumor cells disrupt the lung microenvironment to promote tumor growth. Single-cell RNA sequencing and spatial transcriptomics demonstrated osteosarcoma–epithelial cell interactions in a chronic state of wound healing in the lung. Nintedanib administration significantly disrupted metastatic progression compared with the vehicle control, demonstrating a potential novel therapeutic for combating osteosarcoma lung metastasis. Supported by ORIP (K01OD031811), NCI, and NCATS.
SREBP-Dependent Regulation of Lipid Homeostasis Is Required for Progression and Growth of Pancreatic Ductal Adenocarcinoma
Ishida et al., Cancer Research Communications. 2024.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11444119
Lipids are crucial for tumor cell proliferation, and sterol regulatory element-binding protein (SREBP) activation drives lipid synthesis and uptake to maintain cancer growth. This study investigated the role of the SREBP pathway and its regulator, SREBP cleavage–activating protein (SCAP), in lipid metabolism during the development and progression of pancreatic ductal adenocarcinoma (PDAC). Using female mouse xenograft models and male and female pancreas-specific Scap knockout transgenic mice, researchers demonstrated that SCAP is essential for PDAC progression in low-nutrient conditions, linking lipid metabolism to tumor growth. These findings highlight SREBP as a key therapeutic target for PDAC, offering potential strategies for improving treatment by disrupting cancer-associated metabolic reprogramming. Supported by ORIP (T32OD011089), NCI, NHLBI, and NIGMS.
SIV-Specific Antibodies Protect Against Inflammasome-Driven Encephalitis in Untreated Macaques
Castell et al., Cell Reports. 2024.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11552693
Viral infections are the most common infectious cause of encephalitis, and simian immunodeficiency virus (SIV)–infected macaques are a well-established model for HIV. Researchers investigated the protective effects of SIV-specific antibodies against inflammation-driven encephalitis in using untreated, SIV-infected, male and female pigtail and rhesus macaques. Findings indicate that these antibodies reduce neuroinflammation and encephalitis, highlighting the importance of antibodies in controlling neuroimmune responses, especially in the absence of antiretroviral therapy. This study provides insight into immune-modulatory approaches to combating inflammation-driven encephalopathies. Supported by ORIP (U42OD013117, T32OD011089), NIDA, NHLBI, NIAID, NINDS, and NIMH.
Multimodal Analysis of Dysregulated Heme Metabolism, Hypoxic Signaling, and Stress Erythropoiesis in Down Syndrome
Donovan et al., Cell Reports. 2024.
https://pubmed.ncbi.nlm.nih.gov/39120971
Down syndrome (DS), a genetic condition caused by the presence of an extra copy of chromosome 21, is characterized by intellectual and developmental disability. Infants with DS often suffer from low oxygen saturation, and DS is associated with obstructive sleep apnea. Investigators assessed the role that hypoxia plays in driving health conditions that are comorbid with DS. A multiomic analysis showed that people with DS exhibit elevated heme metabolism and activated stress erythropoiesis, which are indicators of chronic hypoxia; these results were recapitulated in a mouse model for DS. This study identified hypoxia as a possible mechanism underlying several conditions that co-occur with DS, including congenital heart defects, seizure disorders, autoimmune disorders, several leukemias, and Alzheimer's disease. Supported by ORIP (R24OD035579), NCATS, NCI, and NIAID.
Impaired Axon Initial Segment Structure and Function in a Model of ARHGEF9 Developmental and Epileptic Encephalopathy
Wang et al., PNAS. 2024.
https://www.pnas.org/doi/10.1073/pnas.2400709121
Researchers developed a mouse model carrying the G55A missense variant identified in ARHGEF9 patients with severe epilepsy and neurodevelopmental phenotypes. Using male Arhgef9G55A mice, this study examined behavioral, molecular, and electrophysiological phenotypes in the Arhgef9G55A model of developmental and epileptic encephalopathies (DEE). Researchers found that the G55A variant causes disruption of inhibitory postsynaptic organization and axon initial segment (AIS) architecture, leading to impairment of both synaptic transmission and action potential generation. The effects of Arhgef9G55A on neuronal function affect both intrinsic and synaptic excitability and preferentially impair AIS. These findings indicate a novel pathological mechanism of DEE and represent a unique example of a neuropathological condition converging from AIS dysfunctions. Supported by ORIP (U54OD020351, U54OD030187, U54OD020351, S10OD026974) and NINDS.
Engineered Deletions of HIV Replicate Conditionally to Reduce Disease in Nonhuman Primates
Pitchai et al., Science. 2024.
https://pubmed.ncbi.nlm.nih.gov/39116226/
Current antiretroviral therapy (ART) for HIV is limited by the necessity for continuous administration. Discontinuation of ART leads to viral rebound. A therapeutic interfering particle (TIP) was developed as a novel single-administration HIV therapy using defective interfering particles. TIP treatment in two humanized mouse models demonstrated a significant reduction in HIV viral load. TIP intervention was completed 24 hours prior to a highly pathogenic simian immunodeficiency virus (SIV) challenge in a nonhuman primate (NHP) rhesus macaque infant model. Compared to untreated SIV infection, NHPs that received TIP treatment displayed no visible signs of SIV-induced AIDS and exhibited improved seroconversion and a significant survival advantage to the 30-week clinical endpoint. Peripheral blood mononuclear cells isolated from HIV-infected patients showed that TIP treatment reduced HIV outgrowth. This study demonstrates the potential use of a single-administration TIP for HIV treatment. Supported by ORIP (P51OD011092, U42OD010426), NCI, NIAID, and NIDA.
The Role of ATP Citrate Lyase in Myelin Formation and Maintenance
Schneider et al., Glia. 2024.
https://pubmed.ncbi.nlm.nih.gov/39318247/
Myelin formation by Schwann cells is critical for peripheral nervous system development and long-term neuronal function. The study examined how acetyl coenzyme A (acetyl-CoA), essential for lipid synthesis in myelin, is derived, with a focus on mitochondrial ATP citrate lysate (ACLY). By using both sexes in a Schwann cell–specific ACLY knockout mouse model, the authors reported that ACLY plays a role in acetyl-CoA supply for myelin maintenance but not myelin formation. ACLY is necessary for sustaining myelin gene expression and preventing nerve injury pathways. This work highlights a unique dependency on mitochondrial acetyl-CoA for Schwann cell integrity, providing insights into lipid metabolism in neuronal repair. Supported by ORIP (T35OD011078), NICHD, and NINDS.
Identifying Mitigating Strategies for Endothelial Cell Dysfunction and Hypertension in Response to VEGF Receptor Inhibitors
Camarda et al., Clinical Science. 2024.
https://pubmed.ncbi.nlm.nih.gov/39282930/
Vascular endothelial growth factor receptor inhibitor (VEGFRi) use can improve survival in patients with advanced solid tumors, but outcomes can worsen because of VEGFRi-induced hypertension, which can increase the risk of cardiovascular mortality. The underlying pathological mechanism is attributed to endothelial cell (EC) dysfunction. The researchers performed phosphoproteomic profiling on human ECs and identified α-adrenergic blockers, specifically doxazosin, as candidates to oppose the VEGFRi proteomic signature and inhibit EC dysfunction. In vitro testing of doxazosin with mouse, canine, and human aortic ECs demonstrated EC-protective effects. In a male C57BL/6J mouse model with VEGFRi-induced hypertension, it was demonstrated that doxazosin prevents EC dysfunction without decreasing blood pressure. In canine cancer patients, both doxazosin and lisinopril improve VEGFRi-induced hypertension. This study demonstrates the use of phosphoproteomic screening to identify EC-protective agents to mitigate cardio-oncology side effects. Supported by ORIP (K01OD028205), NCI, NHGRI, and NIGMS.