Selected Grantee Publications
Alterations in Tumor Aggression Following Androgen Receptor Signaling Restoration in Canine Prostate Cancer Cell Lines
Vasilatis et al., International Journal of Molecular Sciences. 2024.
https://pubmed.ncbi.nlm.nih.gov/39201315
Prostate cancer (PCa) ranks second worldwide in cancer-related mortality, but only a few animal models exhibit naturally occurring PCa that recapitulates the symptoms of the disease. Neutered dogs have an increased risk of PCa and often lack androgen receptor (AR) signaling, which is involved in upregulating tumorigenesis but can also suppress aggressive cell growth. In this study, researchers sought to understand more about the role of AR signaling in canine PCa initiation and progression by restoring AR in canine PCa cell lines and treating them with dihydrotestosterone. One cell line exhibited AR-mediated tumor suppression; one cell line showed altered proliferation (but not migration or invasion); and a third cell line exhibited AR-mediated alterations in migration and invasion (but not proliferation). The study highlights the heterogeneous nature of PCa in dogs and humans but suggests that AR signaling might have therapeutic potential under certain conditions. Supported by ORIP (T32OD011147).
A Novel TGFβ Receptor Inhibitor, IPW-5371, Prevents Diet-induced Hepatic Steatosis and Insulin Resistance in Irradiated Mice
Szalanczy et al., Radiation Research. 2024.
https://pubmed.ncbi.nlm.nih.gov/38772553
Radiation damages adipose progenitor cells and increases liver fibrosis, leading to the development of metabolic-associated fatty liver disease (MAFLD) and insulin resistance. As the number of cancer survivors increases and the risk of accidental radiation exposure rises, there is a pressing need to characterize and mitigate the delayed effects of radiation exposure. Some of these effects are mediated by TGFβ pathway signaling, which increases in response to radiation exposure and causes fibrosis. In this study, IPW-5371—a small-molecule inhibitor of a TGFβ receptor called activin receptor-like kinase 5 (ALK5)—was shown to protect mice from the effects of sublethal whole-body irradiation and chronic consumption of a Western diet. Mice treated with IPW-5371 exhibited lower fibrosis and fat accumulation in the liver, were more responsive to insulin, and had lower circulating triglycerides and better muscle endurance. IPW-5371 is a promising treatment for mitigating the metabolic effects of radiation exposure and preventing MAFLD. Supported by ORIP (T35OD010946, T32OD010957).
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.
Pancreatic Cancer Cells Upregulate LPAR4 in Response to Isolation Stress to Promote an ECM-Enriched Niche and Support Tumour Initiation
Wu et al., Nature Cell Biology. 2023.
https://pubmed.ncbi.nlm.nih.gov/36646789/
Understanding drivers of tumor initiation is critical for cancer therapy. Investigators found transient increase of lysophosphatidic acid receptor 4 (LPAR4) in pancreatic cancer cells exposed to environmental stress or chemotherapy. LPAR4 induced tumor initiation, stress tolerance, and drug resistance by downregulating miR-139-5p, a tumor suppressor, and upregulating fibronectin. These results indicate that LPAR4 enhances cell-autonomous production of a fibronectin-rich extracellular matrix (ECM), allowing cells to survive isolation stress and compensate for the absence of stromal-derived factors by creating their own tumor-initiating niche. Supported by ORIP (K01OD030513, T32OD017863), NCI, and NHLBI.