Abstract 165: CUCDC2 regulates malignant phenotype of triple-negative breast cancer through interacting with â-catenin

Triple-negative breast cancer (TNBC) has the worst prognosis among all subtypes of breast cancer. CUE domain-containing protein-2 (CUEDC2) protein has reported to confer endocrine resistance in breast cancer by down-regulation of estrogen receptor α (ERα) expression. However, the function of CUEDC2 in TNBC subtype is unclear. Here, we showed CUEDC2 is expressed in triple-negative breast cancer and associated with its malignant phenotype. Knockdown of CUEDC2 not only inhibits TNBC cell proliferation, clone formation, migration, and invasion, but also suppresses TNBC stem cell mammosphere formation ability and cancer stem cell markers expression. While over-expression of CUEDC2 enhances its cell malignant phenotype. Furthermore, we determined that the ARM domain of β-catenin interacts with CUE domain of CUEDC2 through immunoprecipitation and pull-down assay. In the 34 TNBC samples, the expression levels of CUEDC2 and β-catenin also showed a positive correlation. Taken together, our study revealed CUEDC2 is associated with malignant phenotype and breast cancer stem cell properties of TNBC by interacting with β-catenin, and suggested that CUEDC2 may be a potential promising prognosis and therapy target for TNBC. Citation Format: Shuyan Han, Hai-Bo Han, Yan-Na Jiao, Pang-Kuo Lo, Yuan Yao, Qun Zhou, Ping-Ping Li. CUCDC2 regulates malignant phenotype of triple-negative breast cancer through interacting with â-catenin [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 165.