PTEN and hepatocellular carcinoma: Furthermore, treatment with CompE resulted in an increase in PTEN transcript levels in both HCC-1954 and HCC-2218 cell lines (Fig. 5d), and an increase in PTEN protein levels in HCC-1954 cells but not MDA-MB-231 cells (Fig. 5e, Supplementary Fig. 3d), indicating that alterations in NOTCH1 and NOTCH2 can contribute to transcriptional repression of PTEN.