Anticancer activity of vitamin d3–tamoxifen combination microemulsion on mcf-7 breast cell line and its synergistic effect

This study investigates the anticancer activity of a combination microemulsion of vitamin D3 and tamoxifen (TMX-VD3 ME) for a synergistic effect on the MCF-7 breast cancer cell line. The combination microemulsion was prepared by dissolving the drugs in oil, mixing the oil with a surfactant, cosurfactant, and water. ME (VD3 1.5 mg mL-1, TMX 10 mg mL-1) was optimized for stability, globule size, and PDI. MTT assay was used to evaluate the cytotoxicity of the microemulsion. The results demonstrated a concentration-dependent increase in cell uptake with a decrease in cell viability. Flow cytometry revealed enhanced apoptosis and cell cycle arrest in G0/G1 phase and 3.45-fold enhanced efficacy in the migration assay. Additionally, the combination TMX-VD3 ME microemulsion exhibited enhanced anticancer efficacy compared to individual treatments of vitamin D3 ME or tamoxifen ME alone, indicating a synergistic effect. The zebrafish model revealed synergistic antiangiogenic activity of the vitamin D3 ME formulations.