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01-01-2015 | Preclinical Study

Sphingosine kinase 1 contributes to leptin-induced STAT3 phosphorylation through IL-6/gp130 transactivation in oestrogen receptor-negative breast cancer

Authors: Heba Alshaker, Qi Wang, Adam E. Frampton, Jonathan Krell, Jonathan Waxman, Mathias Winkler, Justin Stebbing, Colin Cooper, Ernesto Yagüe, Dmitri Pchejetski

Published in: Breast Cancer Research and Treatment | Issue 1/2015

Abstract

Obesity is a known risk factor for breast cancer. We have recently identified that adipokine leptin regulates the expression of a proto-oncogenic enzyme sphingosine kinase 1 (SK1). Signal transducer and activator of transcription 3 (STAT3) has been linked to breast cancer progression and here we investigate the mechanism of leptin-induced STAT3 activation in ER-negative breast cancer. Gene and protein expression in human primary and secondary breast cancer tissues was analysed using quantitative real-time polymerase chain reaction (qRT-PCR) assay and immunofluorescence. Leptin-induced signalling was analysed in human ER-negative breast cancer cells using Western blotting, qRT-PCR and radiolabelling assays. Gene expression and receptor signalling was modified using small interfering RNA and neutralising antibodies. In human ER-negative breast tumours and lymph node metastases, the expression of leptin receptor significantly correlated with SK1. In ER-negative breast cancer cells, SK1 knockdown led to a significant reduction in leptin-induced STAT3 phosphorylation. Knockdown of another known activator of STAT3 signalling, gp130 also resulted in a significant decrease in leptin-induced STAT3 phosphorylation. ELISA assay showed that leptin produces a significant amount of IL-6 in an SK1-dependent manner. IL-6 neutralising antibodies significantly reduced p-STAT3. Immunofluorescent staining of human primary and secondary breast tumours showed significant correlation between SK1 and IL-6 (P < 0.001), SK1 and p-STAT3 (P < 0.01) and IL-6 and p-STAT3 (P < 0.01). Our findings demonstrate that leptin-induced STAT3 is partially cross activated through SK1-mediated IL6 secretion and gp130 activation. Positive correlations in human tissues suggest the potential significance of this pathway in ER-negative breast cancer.

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Kelly T et al (2008) Global burden of obesity in 2005 and projections to 2030. Int J Obes 32:1431–1437CrossRef

Cleary MP, Grossmann ME (2009) Obesity and breast cancer: the estrogen connection. Endocrinology 150:2537–2542. doi:10.1210/En.2009-0070 PubMedCentralPubMedCrossRef

Maccio A et al (2010) Correlation of body mass index and leptin with tumor size and stage of disease in hormone-dependent postmenopausal breast cancer: preliminary results and therapeutic implications. J Mol Med 88:677–686. doi:10.1007/s00109-010-0611-8 PubMedCrossRef

Anderson GL, Neuhouser ML (2012) Obesity and the risk for premenopausal and postmenopausal breast cancer. Cancer Prev Res 5:515–521CrossRef

Miyoshi Y et al (2006) High expression of leptin receptor mRNA in breast cancer tissue predicts poor prognosis for patients with high, but not low, serum leptin levels. Int J Cancer 118:1414–1419. doi:10.1002/ijc.21543 PubMedCrossRef

Ishikawa M, Kitayama J, Nagawa H (2004) Enhanced expression of leptin and leptin receptor (OB-R) in human breast cancer. Clin Cancer Res 10:4325–4331PubMedCrossRef

Zabeau L et al (2003) The ins and outs of leptin receptor activation. FEBS Lett 546:45–50PubMedCrossRef

Ando S, Catalano S (2011) The multifactorial role of leptin in driving the breast cancer microenvironment. Nat Rev Endocrinol 8:263–275PubMedCrossRef

Jiang L, Li Z, Rui L (2008) Leptin stimulates both JAK2-dependent and JAK2-independent signaling pathways. J Biol Chem 283:28066–28073. doi:10.1074/jbc.M805545200 PubMedCentralPubMedCrossRef

10.

Chung SS et al (2014) STAT3 activation in HER2-overexpressing breast cancer promotes epithelial-mesenchymal transition and cancer stem cell traits. Int J Oncol 44:403–411. doi:10.3892/ijo.2013.2195 PubMedCentralPubMed

11.

Wei W et al (2014) STAT3 signaling is activated preferentially in tumor-initiating cells in claudin-low models of human breast cancer. Stem Cells 32:2571–2582. doi:10.1002/stem.1752 PubMedCrossRef

12.

Bohrer LR et al (2014) Activation of the FGFR-STAT3 pathway in breast cancer cells induces a hyaluronan-rich microenvironment that licenses tumor formation. Cancer Res 74:374–386PubMedCentralPubMedCrossRef

13.

Hogstrand C et al (2013) A mechanism for epithelial-mesenchymal transition and anoikis resistance in breast cancer triggered by zinc channel ZIP6 and STAT3 (signal transducer and activator of transcription 3). Biochem J 455:229–237. doi:10.1042/BJ20130483 PubMedCentralPubMedCrossRef

14.

Alshaker H et al (2014) Leptin induces upregulation of sphingosine kinase 1 in oestrogen receptor-negative breast cancer via Src family kinase-mediated, janus kinase 2-independent pathway. Breast Cancer Res 16:426PubMedCrossRef

15.

Alshaker H et al (2013) Therapeutic potential of targeting SK1 in human cancers. Adv Cancer Res 117:143–200PubMedCrossRef

16.

Sauer L et al (2009) Sphingosine kinase 1 inhibition sensitizes hormone-resistant prostate cancer to docetaxel. Int J Cancer 125:2728–2736. doi:10.1002/ijc.24640 PubMedCrossRef

17.

Pchejetski D et al (2011) The involvement of sphingosine kinase 1 in LPS-induced Toll-like receptor 4-mediated accumulation of HIF-1alpha protein, activation of ASK1 and production of the pro-inflammatory cytokine IL-6. Immunol Cell Biol 89:268–274. doi:10.1038/icb.2010.91 PubMedCrossRef

18.

Tartaglia LA et al (1995) Identification and expression cloning of a leptin receptor, OB-R. Cell 83:1263–1271. doi:10.1016/0092-8674(95)90151-5 PubMedCrossRef

19.

Berishaj M et al (2007) Stat3 is tyrosine-phosphorylated through the interleukin-6/glycoprotein 130/Janus kinase pathway in breast cancer. Breast Cancer Res 9:R32. doi:10.1186/bcr1680 PubMedCentralPubMedCrossRef

20.

Naviglio S et al (2009) Leptin enhances growth inhibition by cAMP elevating agents through apoptosis of MDA-MB-231 breast cancer cells. Cancer Biol Ther 8:1183–1190PubMedCrossRef

21.

Pchejetski D et al (2011) Therapeutic potential of targeting sphingosine kinase 1 in prostate cancer. Nat Rev Urol 8:569–678. doi:10.1038/nrurol.2011.117 PubMedCrossRef

22.

Nakashima K, Narazaki M, Taga T (1997) Leptin receptor (OB-R) oligomerizes with itself but not with its closely related cytokine signal transducer gp130. FEBS Lett 403:79–82PubMedCrossRef

23.

Lieblein JC et al (2008) STAT3 can be activated through paracrine signaling in breast epithelial cells. BMC Cancer 8:1471–2407CrossRef

24.

Watson C et al (2010) High expression of sphingosine 1-phosphate receptors, S1P(1) and S1P(3), sphingosine kinase 1, and extracellular signal-regulated kinase-1/2 is associated with development of tamoxifen resistance in estrogen receptor-positive breast cancer patients. Am J Pathol 177:2205–2215. doi:10.2353/ajpath.2010.100220 PubMedCentralPubMedCrossRef

25.

Garcia R et al (1997) Constitutive activation of Stat3 in fibroblasts transformed by diverse oncoproteins and in breast carcinoma cells. Cell Growth Differ 8:1267–1276PubMed

26.

Garcia R et al (2001) Constitutive activation of Stat3 by the Src and JAK tyrosine kinases participates in growth regulation of human breast carcinoma cells. Oncogene 20:2499–2513PubMedCrossRef

27.

Kim SH et al (2011) Benzyl isothiocyanate inhibits oncogenic actions of leptin in human breast cancer cells by suppressing activation of signal transducer and activator of transcription 3. Carcinogenesis 32:359–367. doi:10.1093/carcin/bgq267 PubMedCentralPubMedCrossRef

28.

Saxena NK et al (2007) leptin-induced growth stimulation of breast cancer cells involves recruitment of histone acetyltransferases and mediator complex to CYCLIN D1 promoter via activation of Stat3. J Biol Chem 282:13316–13325PubMedCentralPubMedCrossRef

29.

Dirat B et al (2011) Cancer-associated adipocytes exhibit an activated phenotype and contribute to breast cancer invasion. Cancer Res 71:2455–2465PubMedCrossRef

30.

Fenton JI et al (2006) Interleukin-6 production induced by leptin treatment promotes cell proliferation in an Apc ((Min/+)) colon epithelial cell line. Carcinogenesis 27:1507–1515. doi:10.1093/carcin/bgl018 PubMedCrossRef

31.

Huang WL et al (2010) Signal transducer and activator of transcription 3 activation up-regulates interleukin-6 autocrine production: a biochemical and genetic study of established cancer cell lines and clinical isolated human cancer cells. Mol Cancer 9:1476–4598

32.

Zhang W et al (2014) Adipocyte lipolysis stimulated interleukin-6 production requires sphingosine kinase 1 activity. J Biol Chem 289(46):32178–32185. doi:10.1074/jbc.M114.601096 PubMedCrossRef

Title: Sphingosine kinase 1 contributes to leptin-induced STAT3 phosphorylation through IL-6/gp130 transactivation in oestrogen receptor-negative breast cancer
Authors: Heba Alshaker
Qi Wang
Adam E. Frampton
Jonathan Krell
Jonathan Waxman
Mathias Winkler
Justin Stebbing
Colin Cooper
Ernesto Yagüe
Dmitri Pchejetski
Publication date: 01-01-2015
Publisher: Springer US
Published in: Breast Cancer Research and Treatment / Issue 1/2015
Print ISSN: 0167-6806
Electronic ISSN: 1573-7217
DOI: https://doi.org/10.1007/s10549-014-3228-8

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