Expression of protein tyrosine phosphatase alpha (RPTPalpha) in human breast cancer correlates with low tumor grade, and inhibits tumor cell growth in vitro and in vivo.

TY - JOUR

T1 - Expression of protein tyrosine phosphatase alpha (RPTPalpha) in human breast cancer correlates with low tumor grade, and inhibits tumor cell growth in vitro and in vivo.

AU - Ardini, E

AU - Agresti, R

AU - Tagliabue, E

AU - Greco, M

AU - Aiello, P

AU - Yang, L T

AU - Ménard, S

AU - Sap, J

N1 - Keywords: Animals; Breast Neoplasms; Cell Division; Female; Gene Amplification; Humans; Mammary Neoplasms, Experimental; Mice; Mice, Inbred BALB C; Mice, Nude; Middle Aged; Neoplasm Metastasis; Protein Tyrosine Phosphatases; RNA, Messenger; Receptor-Like Protein Tyrosine Phosphatases, Class 4; Receptors, Cell Surface; Tumor Cells, Cultured

PY - 2000

Y1 - 2000

N2 - Tyrosine phosphorylation is controlled by a balance of tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs). Whereas the contribution of PTKs to breast tumorigenesis is the subject of intense scrutiny, the potential role of PTPs is poorly known. RPTPalpha is implicated in the activation of Src family kinases, and regulation of integrin signaling, cell adhesion, and growth factor responsiveness. To explore its potential contribution to human neoplasia, we surveyed RPTPalpha protein levels in primary human breast cancer. We found RPTPalpha levels to vary widely among tumors, with 29% of cases manifesting significant overexpression. High RPTPalpha protein levels correlated significantly with low tumor grade and positive estrogen receptor status. Expression of RPTPalpha in breast carcinoma cells led to growth inhibition, associated with increased accumulation in G0 and G1, and delayed tumor growth and metastasis. To our knowledge, this is the first example of a study correlating expression level of a specific bona fide PTP with neoplastic disease status in humans.

AB - Tyrosine phosphorylation is controlled by a balance of tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs). Whereas the contribution of PTKs to breast tumorigenesis is the subject of intense scrutiny, the potential role of PTPs is poorly known. RPTPalpha is implicated in the activation of Src family kinases, and regulation of integrin signaling, cell adhesion, and growth factor responsiveness. To explore its potential contribution to human neoplasia, we surveyed RPTPalpha protein levels in primary human breast cancer. We found RPTPalpha levels to vary widely among tumors, with 29% of cases manifesting significant overexpression. High RPTPalpha protein levels correlated significantly with low tumor grade and positive estrogen receptor status. Expression of RPTPalpha in breast carcinoma cells led to growth inhibition, associated with increased accumulation in G0 and G1, and delayed tumor growth and metastasis. To our knowledge, this is the first example of a study correlating expression level of a specific bona fide PTP with neoplastic disease status in humans.

U2 - 10.1038/sj.onc.1203869

DO - 10.1038/sj.onc.1203869

M3 - Journal article

C2 - 11042685

SN - 0950-9232

VL - 19

SP - 4979

EP - 4987

JO - Oncogene

JF - Oncogene

IS - 43

ER -