CXCL8 and breast cancer: When the breast cancer cells were stimulated with LPS for 6 h (LPS1 from S. Typhimurium and LPS2 from E. Coli), we could see that IL-6, IL-8 and TNFα were induced by both LPS1 and LPS2 in the MDA-MB-231, SUM-149 and SUM-159 cell lines, but not the MDA-MB-468 cells with inherent low expression of TLR4 (Fig. 2b).