Soluble factor(s) secreted by MDA-MB-231, MDA-MB-468, and breast cancer associated fibroblasts are sufficient to amplify p-STAT3 (Y705) levels in MDA-MB-453 and MCF-10A. A. MDA-MB-453 cells were co-cultured with MDA-MB-468 cells for 120 hours. B. MCF-10A cells were treated with MDA-MB-468 conditioned media for 6 and 24 hours. C. MCF-10A cells were treated with MDA-MB-231 conditioned media for 0.5 hours. D. MDA-MB-453 cells were treated with MDA-MB-231 conditioned media for various time points between 0.5 and 24 hours. E. MCF-10A cells were treated with MDA-MB-231 conditioned media for 1, 24, and 48 hours. F. MDA-MB-453 cells were treated with conditioned media from breast cancer associated fibroblasts for 0.5 hours. 453: MDA-MB-453; 468: MDA-MB-468; 231: MDA-MB-231; BCF: breast cancer associated fibroblasts; No Tx: no treatment; CM: conditioned media; hr: hour.