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A potential estrogen mimetic effect of a bis(ethyl)polyamine analogue on estrogen receptor positive MCF-7 breast cancer cells

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Abstract

BE-3-3-3-3 (1,15-(ethylamino)4,8,12-triazapentadecane) is a bis(ethyl)polyamine analogue under investigation as a therapeutic agent for breast cancer. Since estradiol (E2) is a critical regulatory molecule in the growth of breast cancer, we examined the effect of BE-3-3-3-3 on estrogen receptor α (ERα) positive MCF-7 cells in the presence and absence of E2. In the presence of E2, a concentration-dependent decrease in DNA synthesis was observed using [3H]-thymidine incorporation assay. In the absence of E2, low concentrations (2.5–10 μM) of BE-3-3-3-3 increased [3H]-thymidine incorporation at 24 and 48 h. BE-3-3-3-3 induced the expression of early response genes, c-myc and c-fos, in the absence of E2, but not in its presence, as determined by real-time quantitative polymerase chain reaction (qPCR). BE-3-3-3-3 had no significant effect on these genes in an ERα-negative cell line, MDA-MB-231. Chromatin immunoprecipitation assay demonstrated enhanced promoter occupation by either E2 or BE-3-3-3-3 of an estrogen-responsive gene pS2/Tff1 by ERα and its co-activator, steroid receptor co-activator 3 (SRC-3). Confocal microscopy of BE-3-3-3-3-treated cells revealed membrane localization of ERα, similar to that induced by E2. The failure of BE-3-3-3-3 to inhibit cell proliferation was associated with autophagic vacuole formation, and the induction of Beclin 1 and MAP LC3 II. These results indicate a differential effect of BE-3-3-3-3 on MCF-7 cells in the absence and presence of E2, and suggest that pre-clinical and clinical development of polyamine analogues might require special precautions and selection of sensitive subpopulation of patients.

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Abbreviations

BE-3-3-3-3:

1,15-(ethylamino)4,8,12-triazapentadecane

BE-3-3-3:

Bis(ethyl) norspermine

APAO:

Acetylpolyamine oxidase

CHIP:

Chromatin immunoprecipitation

DAPI:

4′6′-diamidino-2-phenylindole

E2 :

Estradiol

ER:

Estrogen receptor

ERE:

Estrogen response element

ER(+):

ER-positive

ER(−):

ER-negative

GPR30:

G-protein-coupled receptor homologue 30

MAP LC3:

Microtubule-associated protein 1 light chain 3

N 1-AcSpd:

N 1-acetylspermidine

NCoR:

Nuclear receptor co-repressor

ODC:

Ornithine decarboxylase

Put:

Putrescine

qPCR:

Quantitative polymerase chain reaction

SAMDC:

S-adenosyl l-methionine decarboxylase

STR:

Short tandem repeat

Spd:

Spermidine

Spm:

Spermine

SSAT:

Spermidine/spermine-N1-acetyltransferase

SMO:

Spermine oxidase

SRC-3:

Steroid receptor co-activator 3

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Acknowledgments

The authors thank Mrs. Tuula Reponen, Mrs. Anne Karppinen and Mrs. Arja Korhonen (University of Eastern Finland) for their skilful technical assistance. This work was supported, in part, by grants from the Foundation of UMDNJ (64-09 and PC28-1), Susan G. Komen ‘For The Cure’ grant BCTR 0600180, the Academy of Finland, and by UEF Strategic Funding.

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Authors and Affiliations

  1. Department of Medicine and Cancer Institute of New Jersey, University of Medicine and Dentistry of New Jersey‐Robert Wood Johnson Medical School, New Brunswick, NJ, 08901, USA

    Irina Nayvelt, Shali John & T. J. Thomas

  2. Division of Clinical Immunology and Rheumatology, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294, USA

    Hui-Chen Hsu & PingAr Yang

  3. Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, NY, 14263, USA

    Wensheng Liu & Gokul Das

  4. Department of Biotechnology and Molecular Medicine, A. I. Virtanen Institute for Molecular Sciences, Biocenter Kuopio, University of Eastern Finland, 70210, Kuopio, Finland

    Mervi T. Hyvönen & Leena Alhonen

  5. Department of Biosciences, Laboratory of Chemistry, Biocenter Kuopio, University of Eastern Finland, 70210, Kuopio, Finland

    Tuomo A. Keinänen

  6. Department of Biochemistry and Cellular Physiology, Josai University, Saitama, Japan

    Akira Shirahata

  7. Department of Pathology and Laboratory Medicine, University of Medicine and Dentistry of New Jersey‐Robert Wood Johnson Medical School, New Brunswick, NJ, 08903, USA

    Rajesh Patel

  8. Department of Environmental and Community Medicine and Cancer Institute of New Jersey, University of Medicine and Dentistry of New Jersey‐Robert Wood Johnson Medical School, New Brunswick, NJ, 08901, USA

    Thresia Thomas

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  1. Irina Nayvelt
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Nayvelt, I., John, S., Hsu, HC. et al. A potential estrogen mimetic effect of a bis(ethyl)polyamine analogue on estrogen receptor positive MCF-7 breast cancer cells. Amino Acids 42, 899–911 (2012). https://doi.org/10.1007/s00726-011-1005-0

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