Abstract | INTRODUCTION: METHODS: Induction of apoptosis was analyzed by measurement of the loss of mitochondrial membrane potential. Apoptotic signaling was measured with quantification of activated MAPK p38 and caspase-3 by using the Western blot technique. GnRH-I receptor protein expression was inhibited by using the antisense knockdown technique. In vivo experiments were performed by using nude mice bearing xenografted human breast tumors. RESULTS: We showed that treatment of MCF-7 and triple-negative MDA-MB-231 human breast cancer cells with a GnRH-II antagonist results in apoptotic cell death in vitro via activation of stress-activated MAPK p38 and loss of mitochondrial membrane potential. In addition, we showed GnRH-II antagonist-induced activation of caspase-3 in MDA-MB-231 human breast cancer cells. After knockdown of GnRH-I receptor expression, GnRH-II antagonist-induced apoptosis and apoptotic signaling was only slightly reduced, indicating that an additional pathway mediating the effects of GnRH-II antagonists may exist. The GnRH-I receptor seems not to be the only target of GnRH-II antagonists. The antitumor effects of the GnRH-II antagonist could be confirmed in nude mice. The GnRH-II antagonist inhibited the growth of xenotransplants of human breast cancers in nude mice completely, without any apparent side effects. CONCLUSIONS:
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Authors | Carsten Gründker, Crispin Föst, Stefanie Fister, Nadine Nolte, Andreas R Günthert, Günter Emons |
Journal | Breast cancer research : BCR
(Breast Cancer Res)
Vol. 12
Issue 4
Pg. R49
( 2010)
ISSN: 1465-542X [Electronic] England |
PMID | 20630060
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- DNA, Antisense
- GnRH-II, Ac-2-Nal(1)-4Cpa(2)-3Pal(3,6)-Leu(8)-Ala(10)-
- Protein Precursors
- Receptors, Estrogen
- Receptors, Progesterone
- progonadoliberin I
- Gonadotropin-Releasing Hormone
- LHRH, His(5)-Trp(7)-Tyr(8)-
- Receptor, ErbB-2
- Caspase 3
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Topics |
- Animals
- Apoptosis
(drug effects)
- Breast Neoplasms
(drug therapy, metabolism, pathology)
- Caspase 3
(metabolism)
- Cell Line, Tumor
- DNA, Antisense
(genetics)
- Enzyme Activation
(drug effects)
- Female
- Gonadotropin-Releasing Hormone
(analogs & derivatives, antagonists & inhibitors, genetics, metabolism, pharmacology)
- Humans
- Mammary Neoplasms, Experimental
(drug therapy, metabolism, pathology)
- Mice
- Mice, Nude
- Protein Precursors
(genetics, metabolism)
- Receptor, ErbB-2
(deficiency, genetics)
- Receptors, Estrogen
(deficiency, genetics)
- Receptors, Progesterone
(deficiency, genetics)
- Tumor Burden
(drug effects)
- Xenograft Model Antitumor Assays
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