Effect of Exogenous pH on Cell Growth of Breast Cancer Cells

Abstract

Abstract Breast cancer is the most common cancer in women and the most life-threatening cancer in women worldwide. One key feature of cancer cells including breast cancer cells is a reversed pH gradient, and extracellular pH (pHe) of cancer cells is more acidic than normal cells. Cancer cells have lower pHe of ~ 6.7–7.1 and higher intracellular pH (pHi) of 7.4, while normal cells have pHe of 7.4 and lower pHi of 7.2. Here, we investigated how exogenous pH affected breast cancer cells. MDA-MB-231 cell lines were cultured in five different pHs, pH 6.0, pH 6.7, pH 7.4, pH 8.4, and pH 9.2 of medium. The cells were growing in pH 6.0 and pH 9.2 however, not as fast as in other pHs. Especially they were floating in more acidic conditions than pH 6.3. In alkaline pH (pH 8.4 and pH 9.2), more cells were early apoptotic and they were in S phase. In acidic pH (pH 6.0), more cells were late apoptotic or necrotic and more cells were at G2/M phase in acidic pH (pH 6.0 and pH 6.7). The results suggested that MDA-MB-231 cells experienced different cell growth and cell metabolism in different pHs.