Abstract C124: Assessment of the anticancer potential of a natural compound euphol in colorectal cancer from in vitro and in vivo mouse models
Authors: Alves Ana Laura Vieira , Martin Ana Carolina , Sinha Krishna M , Silva Viviane Aline Oliveira , da Silva-Oliveira Renato José , Teixeira Silvia A , Guimaraes Denise P , Romagnolo Luis Gustavo , Reis Monise Tadin , Duzagac Fahriye , Vilar Eduardo , Reis Rui Manuel 
Published: December 2023

Abstract
Introduction and objectives: Euphol, a tetracyclic triterpene alcohol, is the main component in the sap of the Euphorbiaceae family of plants in subtropical and tropical regions. It has been reported as a modulator of protein kinases C (PKC) activity and to possess several properties, including anti-inflammatory and, more recently, antineoplastic action. These findings further amplified the therapeutic interest in euphol for cancer prevention and treatment. In the present study, we aimed to explore the in vitro and in vivo antitumor effect of synthetic euphol on colorectal cancer (CRC) to provide insight into euphol-based therapies for cancer patients.
Methods: Cytotoxicity potential of commercial synthetic euphol on CRC cell lines (HCT15, LOVO – MSI) and (SW620, HT29 – MSS) and mouse organoids derived from ApcLoxP/+-Cdx2 mice was analyzed by MTS-based viability assay using CellTiterGlo kit. The clonogenic potential of CRC cell lines was assessed following a 10-day treatment with different doses of euphol. Quantitative RT-PCR and Western blot analyses were performed to study the effects of euphol on the gene and protein expression of the PKCs isoforms in CRC cell lines and organoids. In addition, a PDX mouse model was established using a surgical sample from a CRC patient. For in vivo studies, the PDX model and ApcLoxP/+-Cdx2 mice were administered euphol or vehicle by mouth for 10 days to assess the therapeutic effect and 8 weeks to assess the preventive effect, respectively.
Results: Treatment with euphol resulted in reduced cell viability in both MSS and MSI CRC cell lines, and mouse organoids, following a 72-hour exposure. Euphol also promoted the reduction of the clonogenic potential of CRC cell lines in a dose-dependent manner. Further, the PKCα, PKCβ, PKCδ, and PKCZ gene and protein expression were stimulated in euphol-treated organoids, compared to control. Notably, we observed a significant decrease in tumor volume and suppressed tumor growth after 10 days of treatment with euphol in a PDX mouse model. Euphol-treated ApcLoxP/+-Cdx2 mice for 8 weeks also showed reduced colonic polyposis compared to untreated mice.
Conclusions: These results indicate that synthetic euphol has a cytotoxic potential in inhibiting cell proliferation of CRC cells in both 2D and 3D models, and in vivo models through modulation of the expression of genes involved PKC pathway, thus highlighting the therapeutic potential of euphol for CRC.
Citation Format: Ana Laura Vieira Alves, Ana Carolina Martin, Krishna M Sinha, Viviane Aline Oliveira Silva, Renato José da Silva-Oliveira, Silvia A Teixeira, Denise P Guimaraes, Luis Gustavo Romagnolo, Monise Tadin Reis, Fahriye Duzagac, Eduardo Vilar, Rui Manuel Reis. Assessment of the anticancer potential of a natural compound euphol in colorectal cancer from in vitro and in vivo mouse models [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr C124.