Comparison of the Dietary Supplement Protandim and 4‐ Hydroxytamoxifen on Pre‐malignant Human Breast Cancer Cells in 3D Culture

Protandim is a dietary supplement with potent antioxidant properties. We hypothesized that Protandim would inhibit malignant progression of ductal carcinoma in situ (DCIS). A pre‐malignant human breast cancer cell line (MCF10DCIS.com) was grown in collagen type I for 1 week and then cultured for 2 more weeks in the presence or absence of a growth factor (GF) combination of TGF‐beta and CXCL12, 20ng/mL each. In the presence of GF, most cells exhibited long processes and formed interlacing networks and stellate aggregates. Numerous genes and cytokines involved in cancer progression, inflammation, and differentiation were up‐regulated. Bipotency was verified by IHC for pancytokeratin and alpha smooth muscle actin. Additional groups were dosed with 4‐hydroxytamoxifen (2.5 micromolar), Protandim (8 micrograms/mL), or vehicle (0.1% DMSO). In the Protandim and 4‐hydroxytamoxifen groups, more cells displayed a rounded shape with fewer processes. In the cytokine array, the following decreases by Protandim and 4‐hydroxytamoxifen (respectively) were observed: platelet‐derived growth factor (PGDF): 55% & 27%; interleukin 5 (IL‐5): 81% & 76%; monocyte chemotactic protein1 (MCP‐1): 84% & 76%; angiogenin: 68% & 77%; granulocyte‐macrophage colony‐stimulating factor (GM‐CSF): 63% & 44%; interleukin 6 (IL‐6): 77% & 79%. These results suggest Protandim may suppress DCIS progression. (NIH/NCRR)