Figure 1. The combination of low-dose Doxycycline and Azithromycin inhibits mammosphere formation. Note that this combination in MCF7 breast cancer cells, inhibited 3D mammosphere formation with greater efficacy than the two drugs alone. *p < 0.05; ***p < 0.001; ****p < 0.0001. DOX, Doxycycline; AZI, Azithromycin.