scholarly journals Resveratrol Regulates Insulin-Like Growth Factor-II in Breast Cancer Cells

Endocrinology ◽  
2005 ◽  
Vol 146 (10) ◽  
pp. 4224-4233 ◽  
Author(s):  
Sharda Vyas ◽  
Yayesh Asmerom ◽  
Daisy D. De León

IGF-II is a potent mitogen and inhibitor of apoptosis in breast cancer. Regulation of IGF-II is complex and includes inhibition by tumor suppressors, stimulation by oncogenes, and imprinting and hormonal regulation by estrogens. Resveratrol (RSV) is a phytoestrogen that displays estrogen-like agonistic and antagonistic activity. Recent studies have shown that RSV inhibits the growth of breast cancer cells and may represent a potent agent in chemopreventive therapy. Because 17β-estradiol regulates IGF-II, we hypothesized that RSV may have a similar effect on IGF-II. The present study was designed to examine whether: 1) RSV modulates IGF-II in breast cancer cells; 2) regulation of IGF-II by RSV is dependent on the ER status; and 3) IGF-II (not IGF-I) mediates RSV effects on breast cancer cells. Treatment of MCF-7 and T47D cells with RSV (10−6m) caused stimulation of precursor IGF-II mRNA and protein; this effect was blocked by coincubation with 17β-estradiol (10−9m). Cell growth stimulated by RSV (10−6m) was blocked by addition of a blocking IGF-I receptor antibody, or the antiestrogen tamoxifen (10−7m). In contrast, RSV treatment (10−4m) inhibited IGF-II secretion and cell growth in MCF-7 and T47D cells. No increase in IGF-II levels is seen in estrogen receptor (−) MCF-10 cells, even though cell growth was inhibited by RSV 10−4m and precursor IGF-II blocked the inhibitory effect of resveratrol. No change in IGF-I was observed with RSV treatment (10−6 to 10−4m). Our study demonstrates that RSV regulates IGF-II and that IGF-II mediates RSV effect on cell survival and growth in breast cancer cells.

2003 ◽  
Vol 179 (1) ◽  
pp. 55-62 ◽  
Author(s):  
M Alkhalaf ◽  
AM El-Mowafy

We have recently shown that growth inhibition of breast cancer cells by progesterone is due to the induction of cell differentiation, but not apoptosis. Because the tumor suppressor protein p53 plays a central role in normal cell growth and in tumor suppression, we have examined the effect of progesterone on the levels of this protein in MCF-7 cells. We show here that the antiproliferative effect of progesterone is accompanied with down-regulation of endogenous p53 protein. To study the effect of progesterone on cell growth in the presence of normal levels of p53 protein, we used transient transfection to overexpress p53 protein. MCF-7 cells were transfected with a p53 expressing vector that contains p53 human cDNA under the control of a cytomegalovirus promoter. Cell growth, cell viability, and apoptosis were analyzed in the transfected cells after six days of exposure to 100 nM progesterone. We show here that progesterone significantly enhances growth inhibition and apoptosis in MCF-7 cells overexpressing p53, but not in cells transfected with the control vector. These data suggest that re-establishing p53 function in MCF-7 breast cancer cells renders them more sensitive to the growth inhibitory effect of progesterone.


Endocrinology ◽  
2007 ◽  
Vol 148 (8) ◽  
pp. 4091-4101 ◽  
Author(s):  
Robert X.-D. Song ◽  
Zhenguo Zhang ◽  
Yucai Chen ◽  
Yongde Bao ◽  
Richard J. Santen

We present an integrated model of an extranuclear, estrogen receptor-α (ERα)-mediated, rapid MAPK activation pathway in breast cancer cells. In noncancer cells, IGF-I initiates a linear process involving activation of the IGF-I receptor (IGF-IR) and matrix metalloproteinases (MMP), release of heparin-binding epidermal growth factor (HB-EGF), and activation of EGF receptor (EGFR)-dependent MAPK. 17β-Estradiol (E2) rapidly activates IGF-IR in breast cancer cells. We hypothesize that E2 induces a similar linear pathway involving IGF-IR, MMP, HB-EGF, EGFR, and MAPK. Using MCF-7 breast cancer cells, we for the first time demonstrated that a sequential activation of IGF-IR, MMP, and EGFR existed in E2 and IGF-I actions, which was supported by evidence that the selective inhibitors of IGF-IR and MMP or knockdown of IGF-IR all inhibited E2- or IGF-I-induced EGFR phosphorylation. Using the inhibitors and small inhibitory RNA strategies, we also demonstrated that the same sequential activation of the receptors occurred in E2-, IGF-I-, but not EGF-induced MAPK phosphorylation. Additionally, a HB-EGF neutralizing antibody significantly blocked E2-induced MAPK activation, further supporting our hypothesis. The biological effects of sequential activation of IGF-IR and EGFR on E2 stimulation of cell proliferation were also investigated. Knockdown or blockade of IGF-IR significantly inhibited E2- or IGF-I-stimulated but not EGF-induced cell growth. Knockdown or blockade of EGFR abrogated cell growth induced by E2, IGF-I, and EGF, indicating that EGFR is a downstream molecule of IGF-IR in E2 and IGF-I action. Together, our data support the novel view that E2 can activate a linear pathway involving the sequential activation of IGF-IR, MMP, HB-EGF, EGFR, and MAPK.


Biomolecules ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 743
Author(s):  
Oluwaseun Akinyele ◽  
Heather M. Wallace

Breast cancer is a complex heterogeneous disease with multiple underlying causes. The polyamines putrescine, spermidine, and spermine are polycationic molecules essential for cell proliferation. Their biosynthesis is upregulated in breast cancer and they contribute to disease progression. While elevated polyamines are linked to breast cancer cell proliferation, there is little evidence to suggest breast cancer cells of different hormone receptor status are equally dependent on polyamines. In this study, we characterized the responses of two breast cancer cells, ER+ (oestrogen receptor positive) MCF-7 and ER- MDA-MB-231 cell lines, to polyamine modulation and determined the requirement of each polyamine for cancer cell growth. The cells were exposed to DFMO (a polyamine pathway inhibitor) at various concentrations under different conditions, after which several growth parameters were determined. Exposure of both cell lines to DFMO induced differential growth responses, MCF-7 cells showed greater sensitivity to polyamine pathway inhibition at various DFMO concentrations than the MDA-MB-231 cells. Analysis of intracellular DFMO after withdrawal from growth medium showed residual DFMO in the cells with concomitant decreases in polyamine content, ODC protein level, and cell growth. Addition of exogenous polyamines reversed the cell growth inhibition, and this growth recovery appears to be partly dependent on the spermidine content of the cell. Similarly, DFMO exposure inhibits the global translation state of the cells, with spermidine addition reversing the inhibition of translation in the breast cancer cells. Taken together, these data suggest that breast cancer cells are differentially sensitive to the antitumour effects of polyamine depletion, thus, targeting polyamine metabolism might be therapeutically beneficial in breast cancer management based on their subtype.


2003 ◽  
Vol 17 (10) ◽  
pp. 2002-2012 ◽  
Author(s):  
Olga A. Sukocheva ◽  
Lijun Wang ◽  
Nathaniel Albanese ◽  
Stuart M. Pitson ◽  
Mathew A. Vadas ◽  
...  

Abstract Current understanding of cytoplasmic signaling pathways that mediate estrogen action in human breast cancer is incomplete. Here we report that treatment with 17β-estradiol (E2) activates a novel signaling pathway via activation of sphingosine kinase (SphK) in MCF-7 breast cancer cells. We found that E2 has dual actions to stimulate SphK activity, i.e. a rapid and transient activation mediated by putative membrane G protein-coupled estrogen receptors (ER) and a delayed but prolonged activation relying on the transcriptional activity of ER. The E2-induced SphK activity consequently activates downstream signal cascades including intracellular Ca2+ mobilization and Erk1/2 activation. Enforced expression of human SphK type 1 gene in MCF-7 cells resulted in increases in SphK activity and cell growth. Moreover, the E2-dependent mitogenesis were highly promoted by SphK overexpression as determined by colony growth in soft agar and solid focus formation. In contrast, expression of SphKG82D, a dominant-negative mutant SphK, profoundly inhibited the E2-mediated Ca2+ mobilization, Erk1/2 activity and neoplastic cell growth. Thus, our data suggest that SphK activation is an important cytoplasmic signaling to transduce estrogen-dependent mitogenic and carcinogenic action in human breast cancer cells.


Steroids ◽  
2016 ◽  
Vol 115 ◽  
pp. 90-97 ◽  
Author(s):  
Mahmoud Aghaei ◽  
Zeinab Yazdiniapour ◽  
Mustafa Ghanadian ◽  
Behzad Zolfaghari ◽  
Virginia Lanzotti ◽  
...  

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