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Perry, R. J.

Publications and source records attributed to Perry, R. J..

3 recordsLinked to original sources

Gene Expression and Tracer-Based Metabolic Flux Analysis Reveals Tissue-Specific Metabolic Scaling in vitro, ex vivo, and in vivo

Metabolic scaling, the inverse correlation of metabolic rates to body mass, has been appreciated for more than 80 years. Studies of metabolic scaling have almost exclusively been restricted to mathematical modeling of oxygen consumption. The possibility that other metabolic processes scale with body size has not been studied. To address this gap in knowledge, we employed a systems approach spanning from transcriptomics to in vitro and in vivo tracer-based flux. Gene expression in livers of five species spanning a 30,000-fold range in mass revealed differential expression of genes related to cytosolic and mitochondrial metabolic processes, in addition to detoxication of oxidative damage. This suggests that transcriptional scaling of damage control mechanisms accommodates increased oxidative metabolism in smaller species. To determine whether flux through key implicated metabolic pathways scaled, we applied stable isotope tracer methodology to study multiple cellular compartments, tissues, and species. Comparing mice and rats, we demonstrate that while scaling of metabolic fluxes is not observed in the cell-autonomous setting, it is present in liver slices and in vivo. Together, these data reveal that metabolic scaling extends beyond oxygen consumption to numerous other metabolic pathways, and is likely regulated at the level of gene expression and substrate supply.

physiology↗

A Precision Medicine Approach to Metabolic Therapy for Breast Cancer in Mice

Increasing evidence highlights the possibility for approaches targeting metabolism as potential adjuvants to cancer therapy. Sodium-glucose transport protein 2 (SGLT2) inhibitors are the newest class of antihyperglycemic therapies, and have recently been highlighted as a novel therapeutic approach to breast cancer. To our knowledge, however, SGLT2 inhibitors have not been applied in the neoadjuvant setting as a precision medicine approach to combining metabolic therapy with standard of care therapy for this devastating disease. In this study we combine the SGLT2 inhibitor dapagliflozin with paclitaxel chemotherapy in both lean and obese mice. We show that dapagliflozin enhances the efficacy of paclitaxel, reducing tumor glucose uptake and prolonging survival in an insulin-dependent manner in some but not all breast tumors. Our data find a genetic signature for breast tumors most likely to respond to dapagliflozin in combination with paclitaxel. Tumors driven by mutations upstream of canonical insulin signaling pathways are likely to respond to such treatment, whereas tumors driven by mutations downstream of canonical insulin signaling are not. These data demonstrate that dapagliflozin enhances the response to chemotherapy in mice with breast cancer and suggest that breast cancer patients with driver mutations upstream of canonical insulin signaling may be most likely to benefit from this neoadjuvant approach. A clinical trial is currently in preparation, with an application recently submitted for Yale Human Investigations Committee approval, to test this hypothesis in breast cancer patients. One Sentence SummaryWe identify a driver mutation signature by which glucose-wasting metabolic therapy (dapagliflozin) enhances the efficacy of chemotherapy in mice with breast cancer.

cancer biology↗

Multimodal Analysis Reveals Differential Immuno-Metabolic Features in Lung Squamous Cell Carcinoma and Adenocarcinoma

BackgroundThe relationship between systemic metabolism, immune function, and lung cancer is complex and remains poorly defined. Seemingly paradoxically, overweight and obesity confer an improved response to immune checkpoint inhibition in non-small cell lung cancer (NSCLC); however, it is not known whether excess body weight or adiposity impacts the immunometabolic tumor microenvironment. MethodsUtilizing three complementary National Cancer Institute-funded open-source databases containing 18F-fluorodeoxyglucose positron-emission tomography/computed tomography (PET-CT) images for tumor and tissue glucose uptake, adipose tissue and skeletal muscle mass, histology annotated with tumor infiltrating leukocytes, and tumor RNA sequencing, we performed a retrospective cross-sectional analysis to examine phenotypic, metabolic, and genomic intersections of adiposity and tumor immune-metabolism in patients with lung adenocarcinoma (LUAD) versus squamous cell carcinoma (LUSC). ResultsOur data reveal distinct immunometabolomic features of LUSC as compared to LUAD: visceral fat content was negatively correlated with both tumor glucose uptake and leukocyte infiltration. Subcutaneous and visceral adiposity conferred different effects on the tumor genetic landscapes in both tumor types. LUSC tumors showed greater gene expression pathways related to pyruvate, glucose, amino acid, and lipid metabolism, in addition to significantly greater 18F-FDG uptake compared with LUAD, suggesting deeper metabolic regulation within the LUSC tumor microenvironment. ConclusionsSeveral immunometabolomic characteristics of LUSC and LUAD differ, including tumor glucose uptake and the associated metabolic pathways in the tumor, as well as the impact of visceral adiposity on tumor metabolism. These data may highlight opportunities to advance mechanistically targeted precision medicine approaches by better understanding the interplay between metabolic, immunologic, and genomic factors in lung cancer treatment.

cancer biology↗