CXCL8 and breast cancer: In contrast to that assumption, in vitro analysis and deep-sequencing screens including breast cancers (MCF7, T47D, and SKBR3 cell lines, data not shown), revealed consistent and strong expression of IL6 and IL8 by mesenchymal stromal cells and not by carcinoma cells, particularly when the mesenchymal cells were exposed to extracellular acidosis.