PIK3CA and breast cancer: The applied human epithelial MCF10 breast cancer progression model compares the near‐diploid non‐malignant cell line MCF10A forming polarized spheroids (Debnath & Brugge, 2005) with the tumorigenic invasively growing line MCF10CA, which bear activating mutations of HRAS and PIK3CA, and amplified MYC (Maguire et al, 2016).