Endocrinology, Vol 137, 5589-5596, Copyright © 1996 by Endocrine Society

ARTICLES

Estrogen regulates vascular endothelial growth/permeability factor expression in 7,12-dimethylbenz(a)anthracene-induced rat mammary tumors

J Nakamura, A Savinov, Q Lu and A Brodie
Department of Pharmacology and Experimental Therapeutics, School of Medicine, University of Maryland, Baltimore 21201, USA.

Vascular endothelial growth/permeability factor (VEG/PF) is expressed in some normal tissues and at high levels in a wide range of tumors. This growth factor is believed to be a key mediator of angiogenesis. Recent reports have shown that VEG/PF mRNA in the normal rat uterus is stimulated by estradiol (E2). In this study, we investigated the expression of VEG/PF in the mammary gland and 7,12- dimethylbenz(a)anthracene (DMBA)-induced, hormone-dependent mammary tumor of the rat model, and also whether VEG/PF is regulated by E2. VEG/PF mRNA from tumor extracts was amplified by RT-PCR with VEG/PF primers and generated two main products which corresponded in size to those expected for VEG/PF 164 and 120. In some cases, a third product corresponding in size to that expected for VEG/PF 188 was also generated. No such PCR products were generated from equal amount of RNA from normal mammary tissue, rat brain, or liver. Using immunocytochemistry, VEG/PF expression was detected in the epithelial cells of the tumors. We developed an ELISA assay to measure VEG/PF protein concentrations and found a 4-fold difference between normal mammary glands (1.3 +/- 0.11 ng/mg protein) and tumors (4.44 +/- 0.66) (P < 0.01). E2 treatment (5 microg/rat, s.c.) of rats 24 h after ovariectomy, greatly enhanced the expression of RT-PCR products in tumors within 2 h, which reached a maximum at 6-8 h but declined by 48 h. VEG/PF concentrations were also increased 8-12 h after E2 injection. When rats were given two injections of aromatase inhibitor 4- hydroxyandrostenedione (4-OHA 10 mg/rat s.c.) 24 h apart, to reduce estrogen concentrations, a low level of RT-PCR products was maintained for at least 96 h. After a single injection of 4-OHA, RT-PCR products remained low until 36 h when an increase occurred corresponding with a rise in plasma E2 levels. Injection of E2 2 h after 4-OHA treatment, caused a rise in RT-PCR products in 6-8 h. However, there was no significant change in VEG/PF concentrations. An increase in VEG/PF protein concentrations followed the increase in mRNA levels by 4-6 h. Thus, it appears that E2 causes a rapid induction of VEG/PF expression in mammary tumors that is similar to that observed in the normal uterus. These findings suggest that one mechanism by which estrogen acts as a mammary tumor promotor is by stimulating VEG/PF, leading to increased tumor angiogenesis and/or permeability of the microvessels to allow tumor cell migration.

This article has been cited by other articles:

				N. U. Lin and E. P. Winer Advances in Adjuvant Endocrine Therapy for Postmenopausal Women J. Clin. Oncol., February 10, 2008; 26(5): 798 - 805. [Abstract] [Full Text] [PDF]

				H. Buteau-Lozano, G. Velasco, M. Cristofari, P. Balaguer, and M. Perrot-Applanat Xenoestrogens modulate vascular endothelial growth factor secretion in breast cancer cells through an estrogen receptor-dependent mechanism J. Endocrinol., February 1, 2008; 196(2): 399 - 412. [Abstract] [Full Text] [PDF]

				H. Hamada, M. K. Kim, A. Iwakura, M. Ii, T. Thorne, G. Qin, J. Asai, Y. Tsutsumi, H. Sekiguchi, M. Silver, et al. Estrogen Receptors {alpha} and {beta} Mediate Contribution of Bone Marrow-Derived Endothelial Progenitor Cells to Functional Recovery After Myocardial Infarction Circulation, November 21, 2006; 114(21): 2261 - 2270. [Abstract] [Full Text] [PDF]

				S M Hyder Sex-steroid regulation of vascular endothelial growth factor in breast cancer. Endocr. Relat. Cancer, September 1, 2006; 13(3): 667 - 687. [Abstract] [Full Text] [PDF]

				Y. Liang, R. A Brekken, and S. M Hyder Vascular endothelial growth factor induces proliferation of breast cancer cells and inhibits the anti-proliferative activity of anti-hormones. Endocr. Relat. Cancer, September 1, 2006; 13(3): 905 - 919. [Abstract] [Full Text] [PDF]

				A. Bottini, D. Generali, M. P. Brizzi, S. B. Fox, A. Bersiga, S. Bonardi, G. Allevi, S. Aguggini, G. Bodini, M. Milani, et al. Randomized Phase II Trial of Letrozole and Letrozole Plus Low-Dose Metronomic Oral Cyclophosphamide As Primary Systemic Treatment in Elderly Breast Cancer Patients J. Clin. Oncol., August 1, 2006; 24(22): 3623 - 3628. [Abstract] [Full Text] [PDF]

				K. J. Higgins, S. Liu, M. Abdelrahim, K. Yoon, K. Vanderlaag, W. Porter, R. P. Metz, and S. Safe Vascular Endothelial Growth Factor Receptor-2 Expression Is Induced by 17{beta}-Estradiol in ZR-75 Breast Cancer Cells by Estrogen Receptor {alpha}/Sp Proteins Endocrinology, July 1, 2006; 147(7): 3285 - 3295. [Abstract] [Full Text] [PDF]

				S. E. Bulun, Z. Lin, G. Imir, S. Amin, M. Demura, B. Yilmaz, R. Martin, H. Utsunomiya, S. Thung, B. Gurates, et al. Regulation of Aromatase Expression in Estrogen-Responsive Breast and Uterine Disease: From Bench to Treatment Pharmacol. Rev., September 1, 2005; 57(3): 359 - 383. [Abstract] [Full Text] [PDF]

				H. S. Rugo Bevacizumab in the Treatment of Breast Cancer: Rationale and Current Data Oncologist, June 1, 2004; 9(suppl_1): 43 - 49. [Abstract] [Full Text] [PDF]

				J. Wu, J. Richer, K. B. Horwitz, and S. M. Hyder Progestin-Dependent Induction of Vascular Endothelial Growth Factor in Human Breast Cancer Cells: Preferential Regulation by Progesterone Receptor B Cancer Res., March 15, 2004; 64(6): 2238 - 2244. [Abstract] [Full Text] [PDF]

				W. E. Criss Molecular Mechanisms of Toxic Chemicals Indoor and Built Environment, December 1, 2003; 12(6): 395 - 399. [Abstract] [PDF]

				N. J. Mabjeesh, M. T. Willard, C. E. Frederickson, H. Zhong, and J. W. Simons Androgens Stimulate Hypoxia-inducible Factor 1 Activation via Autocrine Loop of Tyrosine Kinase Receptor/Phosphatidylinositol 3'-Kinase/Protein Kinase B in Prostate Cancer Cells Clin. Cancer Res., July 1, 2003; 9(7): 2416 - 2425. [Abstract] [Full Text] [PDF]

				E. M. J. J. Berns, J. G. M. Klijn, M. P. Look, N. Grebenchtchikov, R. Vossen, H. Peters, A. Geurts-Moespot, H. Portengen, I. L. van Staveren, M. E. Meijer-van Gelder, et al. Combined Vascular Endothelial Growth Factor and TP53 Status Predicts Poor Response to Tamoxifen Therapy in Estrogen Receptor-positive Advanced Breast Cancer Clin. Cancer Res., April 1, 2003; 9(4): 1253 - 1258. [Abstract] [Full Text] [PDF]

				H. Buteau-Lozano, M. Ancelin, B. Lardeux, J. Milanini, and M. Perrot-Applanat Transcriptional Regulation of Vascular Endothelial Growth Factor by Estradiol and Tamoxifen in Breast Cancer Cells: A Complex Interplay between Estrogen Receptors {alpha} and {beta} Cancer Res., September 1, 2002; 62(17): 4977 - 4984. [Abstract] [Full Text] [PDF]

				J. A. Foekens, H. A. Peters, N. Grebenchtchikov, M. P. Look, M. E. Meijer-van Gelder, A. Geurts-Moespot, T. H. van der Kwast, C. G. J. Sweep, and J. G. M. Klijn High Tumor Levels of Vascular Endothelial Growth Factor Predict Poor Response to Systemic Therapy in Advanced Breast Cancer Cancer Res., July 1, 2001; 61(14): 5407 - 5414. [Abstract] [Full Text] [PDF]

				D. Marcantonio, L. E. Chalifour, M. A. Alaoui-Jamali, L. Alpert, and H. T. Huynh Cloning and Characterization of a Novel Gene That Is Regulated by Estrogen and Is Associated with Mammary Gland Carcinogenesis Endocrinology, June 1, 2001; 142(6): 2409 - 2418. [Abstract] [Full Text] [PDF]

				R. C. Hovey, A. S. Goldhar, J. Baffi, and B. K. Vonderhaar Transcriptional Regulation of Vascular Endothelial Growth Factor Expression in Epithelial and Stromal Cells during Mouse Mammary Gland Development Mol. Endocrinol., May 1, 2001; 15(5): 819 - 831. [Abstract] [Full Text]

				N. Kirma, K. Gill, U. Mandava, and R. R. Tekmal Overexpression of Aromatase Leads to Hyperplasia and Changes in the Expression of Genes Involved in Apoptosis, Cell Cycle, Growth, and Tumor Suppressor Functions in the Mammary Glands of Transgenic Mice Cancer Res., March 1, 2001; 61(5): 1910 - 1918. [Abstract] [Full Text]

				S. M. Hyder, Z. Nawaz, C. Chiappetta, and G. M. Stancel Identification of Functional Estrogen Response Elements in the Gene Coding for the Potent Angiogenic Factor Vascular Endothelial Growth Factor Cancer Res., June 1, 2000; 60(12): 3183 - 3190. [Abstract] [Full Text]

				M. P. V. Shekhar, J. Werdell, and L. Tait Interaction with Endothelial Cells Is a Prerequisite for Branching Ductal-Alveolar Morphogenesis and Hyperplasia of Preneoplastic Human Breast Epithelial Cells: Regulation by Estrogen Cancer Res., January 1, 2000; 60(2): 439 - 449. [Abstract] [Full Text]

				A. C. Levine, X.-H. Liu, P. D. Greenberg, M. Eliashvili, J. D. Schiff, S. A. Aaronson, J. F. Holland, and A. Kirschenbaum Androgens Induce the Expression of Vascular Endothelial Growth Factor in Human Fetal Prostatic Fibroblasts Endocrinology, November 1, 1998; 139(11): 4672 - 4678. [Abstract] [Full Text] [PDF]

				M. Stoner, F. Wang, M. Wormke, T. Nguyen, I. Samudio, C. Vyhlidal, D. Marme, G. Finkenzeller, and S. Safe Inhibition of Vascular Endothelial Growth Factor Expression in HEC1A Endometrial Cancer Cells through Interactions of Estrogen Receptor alpha and Sp3 Proteins J. Biol. Chem., July 21, 2000; 275(30): 22769 - 22779. [Abstract] [Full Text] [PDF]