Nitric Oxide Synthase and Breast Cancer: Role of TIMP-1 in NO-mediated Akt Activation

Ridnour, Lisa A.; Barasch, Kimberly M.; Windhausen, Alisha N.; Dorsey, Tiffany H.; Lizardo, Michael M.; Yfantis, Harris G.; Lee, Dong Hoon; Switzer, Christopher; Cheng, Robert; Heinecke, Julie L.; Brueggemann, Ernst E.; Hines, Harry B.; Khanna, Chand; Glynn, Sharon A.; Ambs, Stefan; Wink, David A.

doi:10.1371/journal.pone.0044081

Cited by 62 publications

(73 citation statements)

References 54 publications

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“…In tumors, nutrient deprivation results from limited vascularization and forces tumor adaptation via activation of angiogenic, invasion, and survival pathways (12). NO augments tumor cell survival, implicating NOS2 as a mediator of tumor survival under these conditions (4,20,34,35). Importantly, the current study shows positive feed-forward regulation of NOS2 protein and mRNA expression by exogenous NO under SW conditions, because AG suppressed NOS2 levels, which then rebounded in the presence of exogenous NO donor.…”

Section: Discussionmentioning

confidence: 49%

“…Under these conditions, we show up-regulation of NO-targeted biomarkers (IL-6, IL-8, S100A8/TLR4, and TIMP1) of cancer progression (4,20) that promote tumor cell survival, proliferation, and migration, which are suppressed by NOS2 inhibition. We also show intracellular mechanisms of NO-mediated feedforward NOS2 regulation.…”

Section: Discussionmentioning

confidence: 90%

“…Importantly, the current study shows positive feed-forward regulation of NOS2 protein and mRNA expression by exogenous NO under SW conditions, because AG suppressed NOS2 levels, which then rebounded in the presence of exogenous NO donor. We have shown that the TIMP1 protein predicted poor breast cancer survival and activated Akt/BAD signaling in patients with high tumor NOS2 expression (20). Also, TIMP1 nitration correlated with NOinduced PI3k/Akt/BAD prosurvival signaling in MDA-MB-231 cells (20).…”

Section: Discussionmentioning

confidence: 93%

“…Also, immunoprecipitated TIMP1 protein exhibited increased 3NT levels. Toward this end, we have reported maximal TIMP1 nitration at two tyrosine residues under conditions of ∼400 nM steady-state NO flux, which maximally activated PI3k/Akt signaling through interaction with CD63 (20).…”

Section: Nos2 Drivesmentioning

confidence: 96%

“…Tissue inhibitor matrix metalloproteinase-1 (TIMP1) is an additional biomarker that predicts poor breast cancer patient survival and correlates with increased PI3k/Akt activation in patients with high NOS2 tumor expression (20). TIMP1 expression and tyrosine nitration (3NT) was examined under conditions of IFN-γ/SW with or without AG.…”

Section: Nos2 Drivesmentioning

confidence: 99%

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Tumor microenvironment-based feed-forward regulation of NOS2 in breast cancer progression

Heinecke¹,

Ridnour²,

Cheng³

et al. 2014

Proc. Natl. Acad. Sci. U.S.A.

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164

151

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Inflammation is widely recognized as an inducer of cancer progression. The inflammation-associated enzyme, inducible nitric oxide synthase (NOS2), has emerged as a candidate oncogene in estrogen receptor (ER)-negative breast cancer, and its increased expression is associated with disease aggressiveness and poor survival. Although these observations implicate NOS2 as an attractive therapeutic target, the mechanisms of both NOS2 induction in tumors and nitric oxide (NO)-driven cancer progression are not fully understood. To enhance our mechanistic understanding of NOS2 induction in tumors and its role in tumor biology, we used stimulants of NOS2 expression in ER − and ER + breast cancer cells and examined downstream NO-dependent effects. Herein, we show that up-regulation of NOS2 occurs in response to hypoxia, serum withdrawal, IFN-γ, and exogenous NO, consistent with a feed-forward regulation of NO production by the tumor microenvironment in breast cancer biology. Moreover, we found that key indicators of an aggressive cancer phenotype including increased S100 calcium binding protein A8, IL-6, IL-8, and tissue inhibitor matrix metalloproteinase-1 are up-regulated by these NOS2 stimulants, whereas inhibition of NOS2 in MDA-MB-231 breast cancer cells suppressed these markers. Moreover, NO altered cellular migration and chemoresistance of MDA-MB-231 cells to Taxol. Most notably, MDA-MB-231 tumor xenographs and cell metastases from the fat pad to the brain were significantly suppressed by NOS2 inhibition in nude mice. In summary, these results link elevated NOS2 to signals from the tumor microenvironment that arise with cancer progression and show that NO production regulates chemoresistance and metastasis of breast cancer cells.I nflammation is a major component of the tumor microenvironment and a driving force in cancer initiation, promotion, and progression (1-3). Epithelial cancers express markers of inflammation that promote disease progression and drug resistance through evasion of cell death pathways and increased tumor metastasis. Rapid cancer growth leads to tumor hypoxia and nutrient deprivation, which promotes chronic inflammatory feed-forward signaling and selection of resistant tumors that are clinically challenging and sometimes untreatable.Several proinflammatory proteins such as COX2, NF-κB, IL-6, IL-8, S100 calcium binding protein A8 (S100A8), and VEGF are markers of chronic inflammation in the tumor microenvironment. In addition, these proinflammatory mediators directly correlate with inducible nitric oxide synthase (NOS2), which is an emerging biomarker of aggressive tumors that predicts poor survival in patients with elevated tumor NOS2 expression (4-8). These and other clinical studies warrant an improved mechanistic understanding of intratumoral NOS2 regulation and endogenous NO production, which may be therapeutically beneficial.Toward this end, our laboratory and others have used NO donors to study NO signaling in cancer. However, intratumoral NOS2 induction by components of the tumor microenv...

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Section: Discussionmentioning

confidence: 49%

Section: Discussionmentioning

confidence: 90%

Section: Discussionmentioning

confidence: 93%

Section: Nos2 Drivesmentioning

confidence: 96%

Section: Nos2 Drivesmentioning

confidence: 99%

See 3 more Smart Citations

Tumor microenvironment-based feed-forward regulation of NOS2 in breast cancer progression

Heinecke¹,

Ridnour²,

Cheng³

et al. 2014

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

164

151

View full text Add to dashboard Cite

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Tetraspanin CD63 acts as a pro‐metastatic factor via β‐catenin stabilization

Seubert

Cui

Simonavicius

et al. 2014

Intl Journal of Cancer

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The tetraspanin CD63 is implicated in pro-metastatic signaling pathways but, so far, it is unclear, how CD63 levels affect the tumor cell phenotype. Here, we investigated the effect of CD63 modulation in different metastatic tumor cell lines. In vitro, knock down of CD63 induced a more epithelial-like phenotype concomitant with increased E-cadherin expression, downregulation of its repressors Slug and Zeb1, and decreased N-cadherin. In addition, b-catenin protein was markedly reduced, negatively affecting expression of the target genes MMP-2 and PAI-1. b-catenin inhibitors mimicked the epithelial phenotype induced by CD63 knock down. Inhibition of b-catenin upstream regulators PI3K/AKT or GSK3b could rescue the mesenchymal phenotype underlining the importance of the b-catenin pathway in CD63-regulated cell plasticity. CD63 knock down-induced phenotypical changes correlated with a decrease of experimental metastasis whereas CD63 overexpression enhanced the tumor cell-intrinsic metastatic potential. Taken together, our data show that CD63 is a crucial player in the regulation of the tumor cell-intrinsic metastatic potential by affecting cell plasticity.Metastasis is the major cause of death in cancer patients suffering from solid tumors. 1 Epithelial-mesenchymal transition (EMT) is a prerequisite for successful dissemination and colonization of secondary organs by tumor cells. 2 EMT has been shown to result in increased cancer cell motility by reorganization of actin filaments, downregulation of E-Cadherin and increased expression of N-Cadherin. 2-4 Molecular regulators of EMT are the transcription factors Snail, the bHLH and ZFH protein families (Zeb1 and Zeb2), which suppress the gene expression signature assigned to the epithelial phenotype. 3,5 MicroRNAs (miRNAs), including members of the miR-200 family, for example miR-141, have been shown in turn to suppress Zeb proteins, adding an additional level of regulation. 6 In addition, b-Catenin, which is regulated by Glycogen synthase kinase 3 beta (GSK3b) phosphorylation, 7 is shown to play a decisive role in EMT-induction by its ability to both, sense E-Cadherin status and control gene expression of target genes like MMP-2 and PAI-1. 4 EMT is regulated by different cytokines and growth factors, including TGF-b1. 3 Mesenchymal-to-epithelial transition (MET) gained recognition as a crucial process for successful metastasis formation, as tumor cells switch back to a more epithelial phenotype at the site of metastatic outgrowth. 5 Therefore, cellular plasticity and regulation of these alternating phenotypes are of importance during metastatic cancer progression. 5 Tetraspanins seem to play a role in cancer progression. Some family members are described to exert pro-metastatic properties, whereas others are reported to inhibit metastasis. 8 This protein family displays four membrane-spanning domains and their ability to form multiprotein complexes by interacting with other tetraspanins and also with a variety of other transmembrane and cytosolic proteins. [9][10][11] ...

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