STAT3 and breast cancer: Thus, we examined the phosphorylation status of 10 protein kinases as well as two transcription factors (c-Jun and Stat3) in normal primary human mammary epithelial cells (HMEC), telomerase-immortalised human breast cells (TERT), and breast cancer cell lines (MDA-MB-468 and MCF-7) using Kinexus phosphorylated protein screening assays.