Viral nanoparticles (VNPs) based on BMV (Brome mosaic virus) and CCMV (Cowpea chlorotic mottle virus) were developed for targeted delivery of N-desmethyl-tamoxifen (NDMT), an active metabolite of tamoxifen with potent antiestrogenic activity. In silico simulations predicted that BMV could load 20% more NDMT than CCMV, which was experimentally confirmed by fluorescence assays and physicochemical characterization. VNPs showed efficient cell internalization in triple-negative breast cancer cells (4T1), localizing both in the cytoplasm and the nucleus, where NDMT exerts its therapeutic action. Cell viability assays revealed that BMV-NDMT and CCMV-NDMT are significantly more effective than the free NDMT, showing lower IC50 in both cell lines. Furthermore, in a 4T1 murine breast cancer model, BMV-NDMT reduced tumor volume by 44% and lung metastasis by 74%, demonstrating superior antitumor and antimetastatic activities compared to controls. These results highlight the potential of VNPs from plant viruses as efficient and biocompatible delivery systems for breast cancer treatment, with significantly lower doses than free drug.
Garcia et al. (Fri,) studied this question.