title: Signal transducer and activator of transcription 5a inhibited by pimozide may regulate survival of goat mammary gland epithelial cells by regulating parathyroid hormone-related protein.
abstract: The signal transducer and activator of transcription 5a (Stat5a) modulates genes involved in proliferation and survival and plays pivotal roles in regulating the function of the mammary gland during pregnancy, lactation, and involution. However, there is little information about the effects of Stat5a on apoptosis of goat mammary gland epithelial cells (GMECs). In addition, parathyroid hormone-related protein (PTHrP) is a key regulator in cellular calcium transport, mammary gland development and breast tumor biology. This study aimed to explore the interaction of Stat5a and PTHrP in GMEC apoptosis. Quantitative real time PCR (qRT-PCR) suggested that Stat5a was predominantly expressed in the mammary gland, lung, liver and spleen of goats. Treating the GMECs with pimozide, an inhibitor of Stat5a that decreases Stat5a tyrosine phosphorylation, increased PTHrP levels in GMECs in a dose-dependent manner and simultaneously promoted apoptosis of the GMECs. We also demonstrated that PTHrP inhibition induced GMEC apoptosis and restrained cell proliferation. In contrast, PTHrP overexpression protected GMECs from pimozide- and calcium-induced apoptosis, and promoted cell proliferation. Furthermore, pimozide and CaCl2 downregulated the antiapoptotic protein Bcl-2 mRNA expression, respectively, and these effects were protected by PTHrP overexpression. Interestingly, we also found that Stat5a suppressed the expression of matrix metalloproteinase 9 (MMP-9) which can induce goat mammary epithelial cell migration, but PTHrP increased MMP-9 mRNA level. Thus, Stat5a may regulate GMEC survival by regulating the expression of PTHrP.
authors.affiliation: College of Animal Science and Technology, Northwest A&F University, Key Laboratory of Molecular Biology for Agriculture, Yangling, Shaanxi 712100, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.affiliation: College of Animal Science and Technology, Northwest A&F University, Key Laboratory of Molecular Biology for Agriculture, Yangling, Shaanxi 712100, China. Electronic address: zhenghuiling@nwsuaf.edu.cn.
authors.forename: Huiling
authors.initials: H
authors.lastname: Zheng
authors.affiliation: College of Animal Science and Technology, Northwest A&F University, Key Laboratory of Molecular Biology for Agriculture, Yangling, Shaanxi 712100, China.
authors.forename: Yongsen
authors.initials: Y
authors.lastname: Sun
authors.affiliation: College of Animal Science and Technology, Northwest A&F University, Key Laboratory of Molecular Biology for Agriculture, Yangling, Shaanxi 712100, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Yu
authors.affiliation: College of Animal Science and Technology, Northwest A&F University, Key Laboratory of Molecular Biology for Agriculture, Yangling, Shaanxi 712100, China.
authors.forename: Lihui
authors.initials: L
authors.lastname: Li
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000235:genetics; D001483:Base Sequence; D002118:Calcium / Q000378:metabolism / Q000494:pharmacology; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects / Q000235:genetics; D002478:Cells, Cultured; D018492:Dopamine Antagonists / Q000494:pharmacology; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D005260:Female; D005434:Flow Cytometry; D015870:Gene Expression / Q000187:drug effects; D020869:Gene Expression Profiling; D006041:Goats / Q000235:genetics* / Q000378:metabolism; D008321:Mammary Glands, Animal / Q000166:cytology / Q000378:metabolism*; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D044162:Parathyroid Hormone-Related Protein / Q000235:genetics* / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D010802:Phylogeny; D010868:Pimozide / Q000494:pharmacology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D050799:STAT5 Transcription Factor / Q000145:classification / Q000235:genetics* / Q000378:metabolism
chemical_list: D018492:Dopamine Antagonists; D044162:Parathyroid Hormone-Related Protein; D019253:Proto-Oncogene Proteins c-bcl-2; D050799:STAT5 Transcription Factor; D010868:Pimozide; D020780:Matrix Metalloproteinase 9; D002118:Calcium
keywords: Apoptosis; Cell proliferation; Goat; PTHrP; Stat5a