As shown in Figures 2C and 2D, highly invasive and acid-tolerant triple-negative breast cancer (TNBC) MDA-MB-231 cells express significantly higher levels (>750-fold) of TDAG8, while less invasive and estrogen receptor-positive MCF7 and T47D cells have very high levels of OGR1. The gene discussed is ESR1; the disease is triple-negative breast carcinoma.