PPP2CA and breast cancer: Notably, PP2A-C was virtually fully methylated in MDA-MB-231 breast cancer cells, since different Abs recognizing the demethylated catalytic subunit detected PP2A-C in MDA-MB-231 cell lysates only after demethylation by alkaline hydrolysis (NaOH)23, while an Ab against the central region of the subunit recognized the PP2A-C independently of methylation (Fig. 1h).