HCC-1937, MDA-MB-436 and BT-549 cells were null for PTEN protein expression (Supplementary Figure S2 and Supplementary Table S3 at http://www.biochemj.org/bj/452/bj4520499add.htm) whereas JIMT-1 cells have an activating mutation in the catalytic subunit of PI3K (C420R) [27]. The gene discussed is PTEN; the disease is hepatocellular carcinoma.