FTY720 restores the activity of the phosphatase PP2A in specific breast cancer cell lines

Abstract

Triple negative breast cancer (TNBC) patients derive little benefit from target-specific therapies due to lack of the favourable prognostic targets oestrogen/progesterone receptor and human epidermal growth factor receptor type 2 (HER2). The cBioPortal for Cancer Genomics shows that the protein phosphatase 2 (PP2A) is deregulated in 59.6% of basal breast tumours. Patients exhibit either homozygous deletion or underexpression of PP2A, but also overexpression of PP2A inhibitors namely CIP2A, SET, SETBP1 or IGBP1. FTY720, a pharmacological activator of PP2A may help restore its activity, ultimately reversing the constitutive proliferation. In this study we tested the efficacy of FTY720 on a number of breast cancer cell lines. [Excerpt]