Selected Grantee Publications
Tumor Explants Elucidate a Cascade of Paracrine SHH, WNT, and VEGF Signals Driving Pancreatic Cancer Angiosuppression
Hasselluhn et al., Cancer Discovery. 2024.
https://pubmed.ncbi.nlm.nih.gov/37966260/
This study presents a key mechanism that prevents pancreatic ductal adenocarcinoma (PDAC) from undergoing neoangiogenesis, which affects its development, pathophysiology, metabolism, and treatment response. Using human and murine PDAC explants, which effectively retain the complex cellular interactions of native tumor tissues, and single-cell regulatory network analysis, the study identified a cascade of three paracrine pathways bridging between multiple cell types and acting sequentially, Hedgehog to WNT to VEGF, as a key suppressor of angiogenesis in KRAS-mutant PDAC cells. This study provides an experimental paradigm for dissecting higher-order cellular interactions in tissues and has implications for PDAC treatment strategies. Supported by ORIP (S10OD012351, S10OD021764), NCI, and NIDDK.
Epigenetic MLH1 Silencing Concurs With Mismatch Repair Deficiency in Sporadic, Naturally Occurring Colorectal Cancer in Rhesus Macaques
Deycmar et al., Journal of Translational Medicine. 2024.
https://pubmed.ncbi.nlm.nih.gov/38504345
Rhesus macaques serve as a useful model for colorectal cancer (CRC) in humans, but more data are needed to understand the molecular pathogenesis of these cancers. Using male and female rhesus macaques, researchers investigated mismatch repair status, microsatellite instability, genetic mutations, transcriptional differences, and epigenetic alterations associated with CRC. Their data indicate that epigenetic silencing suppresses MLH1 transcription, induces the loss of MLH1 protein, abrogates mismatch repair, and drives genomic instability in naturally occurring CRC in rhesus macaques. This work provides a uniquely informative model for human CRC. Supported by ORIP (P51OD011092, R24OD010947, R24OD021324, P40OD012217, U42OD010426, T35OD010946, T32OD010957), NCATS, and NCI.
Using Mass Spectrometry Imaging to Map Fluxes Quantitatively in the Tumor Ecosystem
Schwaiger-Haber et al., Nature Communications. 2023.
https://pubmed.ncbi.nlm.nih.gov/37208361/
Mass spectrometry imaging (MSI) can be used to identify metabolic patterns within different microenvironments of tumors but has not been fully integrated into metabolomics workflows. Investigators developed an integrated approach by combining MSI, stable isotope labeling, and a spatial variant of Isotopologue Spectral Analysis to study metabolic pathways across the brains of mice harboring GL261 glioma, a mouse model for glioblastoma. This study reveals the importance of multiple anabolic pathways, including fatty acid elongation flux, in glioma. Supported by ORIP (R24OD024624).
Single-Cell Protein Activity Analysis Identifies Recurrence-Associated Renal Tumor Macrophages
Obradovic et al., Cell. 2021.
https://doi.org/10.1016/j.cell.2021.04.038
Post-surgery course of clear cell renal carcinoma (ccRCC) is mixed because of the heterogeneity of the disease. Using high-performance computing cluster and storage systems, investigators established an inclusive ccRCC tumor microenvironment (TME) map by using single-cell RNA sequencing data of subpopulations of tumor and tumor-adjacent tissues. Analysis of the data identified key TME subpopulations as well as their master regulators and candidate cell-cell interactions, revealing clinically relevant cell populations. Specifically, the study uncovered a tumor-specific macrophage subpopulation, validated by spatially resolved, quantitative multispectral immunofluorescence. In a large clinical validation cohort, markers of this subpopulation were significantly enriched in tumors from patients who recurred following surgery. Supported by ORIP (S10OD012351, S10OD021764) and others.