None of the tested clinical or pathological parameters (i.e., patient age, tumor size, histology, malignancy grade, estrogen receptor status, HER2 status) showed independent value to predict the capacity for CO2/HCO3–-independent net acid extrusion mediated by Na+/H+ exchange (Figure 6C) or the capacity for CO2/HCO3–-dependent net acid extrusion mediated by Na+,HCO3– cotransport (Figure 6D) during intracellular acidification. The gene discussed is ESR1; the disease is neoplasm.