We used a previously described small molecule Tlr-4 agonist, PBI1, which had been shown to induce M1-like polarization and enhance macrophage anti-cancer activity in vitro (43). We generated spheroids using 4T1 and EMT6 cells and using only those that were 400 μm or more in diameter, compared non-treated 4T1 or EMT6 spheroid co-cultures with PBI1-treated groups. The gene discussed is TLR4; the disease is cancer.