Epithelial protein-tyrosine phosphatase 1B contributes to the induction of mammary tumors by HER2/Neu but is not essential for tumor maintenance.

ABSTRACT: Protein-tyrosine phosphatase 1B (PTP1B), a well-established metabolic regulator, plays an important role in breast cancer. Using whole-body PTP1B knockout mice, recent studies have shown that PTP1B ablation delays HER2/Neu-induced mammary cancer. Whether PTP1B plays a cell-autonomous or a noncell-autonomous role in HER2/Neu-evoked tumorigenesis and whether it is involved in tumor maintenance was unknown. We generated mice expressing HER2/Neu and lacking PTP1B specifically in the mammary epithelium. We found that mammary-specific deletion of PTP1B delays the onset of HER2/Neu-evoked mammary tumors, establishing a cell autonomous role for PTP1B in such neoplasms. We also deleted PTP1B in established mouse mammary tumors or depleted PTP1B in human breast cancer cell lines grown as xenografts.

SUBMITTER: Balavenkatraman KK 

PROVIDER: S-EPMC3580839 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature