TY - JOUR
T1 - Aberrantly high expression of the CUB and zona pellucida-like domain-containing protein 1 (CUZD1) in mammary epithelium leads to breast tumorigenesis
AU - Mapes, Janelle
AU - Anandan, Lavanya
AU - Li, Quanxi
AU - Neff, Alison
AU - Clevenger, Charles V.
AU - Bagchi, Indrani C.
AU - Bagchi, Milan K.
N1 - Funding Information:
This work was supported by the Eunice Kennedy Shriver NICHD/National Institutes of Health through cooperative agreement U54 HD055787 as part of the Specialized Cooperative Centers Program in Reproduction and Infer-tility Research. The authors declare that they have no conflicts of interest with the contents of this article. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
Publisher Copyright:
© 2018 by The American Society for Biochemistry and Molecular Biology, Inc.
PY - 2018/2/23
Y1 - 2018/2/23
N2 - The peptide hormone prolactin (PRL) and certain members of the epidermal growth factor (EGF) family play central roles in mammary gland development and physiology, and their dysregulation has been implicated in mammary tumorigenesis. Our recent studies have revealed that the CUB and zona pellucidalike domain-containing protein 1 (CUZD1) is a critical factor for PRL-mediated activation of the transcription factor STAT5 in mouse mammary epithelium. Of note, CUZD1 controls production of a specific subset of the EGF family growth factors and consequent activation of their receptors. Here, we found that consistent with this finding, CUZD1 overexpression in nontransformed mammary epithelial HC11 cells increases their proliferation and induces tumorigenic characteristics in these cells. When introduced orthotopically in mouse mammary glands, these cells formed adenocarcinomas, exhibiting elevated levels of STAT5 phosphorylation and activation of the EGF signaling pathway. Selective blockade of STAT5 phosphorylation by pimozide, a small-molecule inhibitor, markedly reduced the production of the EGF family growth factors and inhibited PRLinduced tumor cell proliferation in vitro. Pimozide administration to mice also suppressed CUZD1-driven mammary tumorigenesis in vivo. Analysis of human MCF7 breast cancer cells indicated that CUZD1 controls the production of the same subset of EGF family members in these cells as in the mouse. Moreover, pimozide treatment reduced the proliferation of these cancer cells. Collectively, these findings indicate that overexpression of CUZD1, a regulator of growth factor pathways controlled by PRL and STAT5, promotes mammary tumorigenesis. Blockade of the STAT5 signaling pathway downstream of CUZD1 may offer a therapeutic strategy for managing these breast tumors.
AB - The peptide hormone prolactin (PRL) and certain members of the epidermal growth factor (EGF) family play central roles in mammary gland development and physiology, and their dysregulation has been implicated in mammary tumorigenesis. Our recent studies have revealed that the CUB and zona pellucidalike domain-containing protein 1 (CUZD1) is a critical factor for PRL-mediated activation of the transcription factor STAT5 in mouse mammary epithelium. Of note, CUZD1 controls production of a specific subset of the EGF family growth factors and consequent activation of their receptors. Here, we found that consistent with this finding, CUZD1 overexpression in nontransformed mammary epithelial HC11 cells increases their proliferation and induces tumorigenic characteristics in these cells. When introduced orthotopically in mouse mammary glands, these cells formed adenocarcinomas, exhibiting elevated levels of STAT5 phosphorylation and activation of the EGF signaling pathway. Selective blockade of STAT5 phosphorylation by pimozide, a small-molecule inhibitor, markedly reduced the production of the EGF family growth factors and inhibited PRLinduced tumor cell proliferation in vitro. Pimozide administration to mice also suppressed CUZD1-driven mammary tumorigenesis in vivo. Analysis of human MCF7 breast cancer cells indicated that CUZD1 controls the production of the same subset of EGF family members in these cells as in the mouse. Moreover, pimozide treatment reduced the proliferation of these cancer cells. Collectively, these findings indicate that overexpression of CUZD1, a regulator of growth factor pathways controlled by PRL and STAT5, promotes mammary tumorigenesis. Blockade of the STAT5 signaling pathway downstream of CUZD1 may offer a therapeutic strategy for managing these breast tumors.
UR - http://www.scopus.com/inward/record.url?scp=85042424892&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85042424892&partnerID=8YFLogxK
U2 - 10.1074/jbc.RA117.000162
DO - 10.1074/jbc.RA117.000162
M3 - Article
C2 - 29321207
AN - SCOPUS:85042424892
VL - 293
SP - 2850
EP - 2864
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 8
ER -