Small molecule intervention of actin-binding protein profilin1 reduces tumor angiogenesis in renal cell carcinoma

Gau, D.; Chawla, P.; Xu, K.; Welling, N.; Antonello, J.; Consoli, C.; Wei, M.; Zdancewicz, S.; DaSilva, M.; Varghese, C.; Francoeur, P.; Shi, H.; Chen, X.; Paranjape, A.; Villanueva, F.; Smithgall, T. E.; VanDemark, A. P.; Koes, D. R.; Huryn, D.; Roy, P.

doi:10.1101/2025.07.18.665115

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bioRxiv · 10.1101/2025.07.18.665115

Small molecule intervention of actin-binding protein profilin1 reduces tumor angiogenesis in renal cell carcinoma

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Abstract

Angiogenesis plays a key role in the development and progression of renal cell carcinoma (RCC). Actin-binding protein profilin-1 (Pfn1) is overexpressed in clear cell RCC predominantly in tumor-associated vascular endothelial cells (ECs). We previously demonstrated that that EC-selective (over)expression of Pfn1 accelerates RCC progression, and conversely, genetic loss of EC-Pfn1 dramatically inhibits tumor angiogenesis impeding tumor initiation and/or progression in RCC, suggesting that Pfn1 could be an actionable therapeutic target in RCC. In this study, we demonstrate that 4,4-((4-bromophenyl)methylene)bis(3,5-dimethyl-1H-pyrazole), a small molecule that we had previously identified as an inhibitor of Pfn1-actin interaction, directly binds to Pfn1 and attenuates tumor angiogenesis when directly administered into subcutaneous RCC tumors. Next, we undertook a chemical optimization approach to design and synthesize 4,4-((4-(trifluoromethyl)phenyl)methylene)bis(3,5-dimethyl-1H-pyrazole), a structural analog of our originally identified inhibitor, that exhibits improved anti-angiogenic efficacy in vitro and in vivo. Finally, we demonstrate that Pfn1 inhibitor is amenable to lipid microbubble encapsulation and release in the tumor microenvironment (TME) by ultrasound-mediated disruption of circulating microbubbles to achieve anti-angiogenic and anti-tumor benefit. In summary, our findings suggest that tumor-localized release of Pfn1 inhibitor could be a potential therapeutic strategy in RCC.

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Gau, D., Chawla, P., Xu, K., Welling, N., Antonello, J., Consoli, C., Wei, M., Zdancewicz, S., DaSilva, M., Varghese, C., Francoeur, P., Shi, H., Chen, X., Paranjape, A., Villanueva, F., Smithgall, T. E., VanDemark, A. P., Koes, D. R., Huryn, D., Roy, P.. 2025-07-21. Small molecule intervention of actin-binding protein profilin1 reduces tumor angiogenesis in renal cell carcinoma. https://doi.org/10.1101/2025.07.18.665115

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