Dataset Information

Antiestrogenic effects of the novel sphingosine kinase-2 inhibitor ABC294640.

ABSTRACT: Alterations in sphingolipid metabolism have been shown to contribute to the development of endocrine resistance and breast cancer tumor survival. Sphingosine kinase (SK), in particular, is overexpressed in breast cancer and is a promising target for breast cancer drug development. In this study, we used the novel SK inhibitor ABC294640 as a tool to explore the relationship between SK and estrogen (E2) receptor (ER) signaling in breast cancer cells. Treatment with ABC294640 decreased E2-stimulated ERE-luciferase activity in both MCF-7 and ER-transfected HEK293 cells. Furthermore, the inhibitor reduced E2-mediated transcription of the ER-regulated genes progesterone receptor and SDF-1. Competitive receptor-binding assays revealed that ABC294640 binds in the antagonist ligand-binding domain of the ER, acting as a partial antagonist similar to tamoxifen. Finally, treatment with ABC294640 inhibited ER-positive breast cancer tumor formation in vivo. After 15 d of treatment with ABC294640, tumor volume was reduced by 68.4% (P < 0.05; n = 5) compared with control tumors, with no marked weight loss or illness. Taken together, these results provide strong evidence that this novel SK inhibitor, which had not previously been known to interact with E2 signaling pathways, has therapeutic potential in treating ER-positive breast cancer via inhibition of both SK and ER signaling.

SUBMITTER: Antoon JW

PROVIDER: S-EPMC2954724 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Antiestrogenic effects of the novel sphingosine kinase-2 inhibitor ABC294640.

Antoon James W JW White Martin D MD Meacham William D WD Slaughter Evelyn M EM Muir Shannon E SE Elliott Steven S Rhodes Lyndsay V LV Ashe Hasina B HB Wiese Thomas E TE Smith Charles D CD Burow Matthew E ME Beckman Barbara S BS

Endocrinology 20100922 11

Alterations in sphingolipid metabolism have been shown to contribute to the development of endocrine resistance and breast cancer tumor survival. Sphingosine kinase (SK), in particular, is overexpressed in breast cancer and is a promising target for breast cancer drug development. In this study, we used the novel SK inhibitor ABC294640 as a tool to explore the relationship between SK and estrogen (E2) receptor (ER) signaling in breast cancer cells. Treatment with ABC294640 decreased E2-stimulate ...[more]

PMID: 20861237

Similar Datasets

Project description:Multiple myeloma (MM) remains an incurable disease in need of the development of novel therapeutic agents and drug combinations. ABT-199 is a specific Bcl-2 inhibitor in clinical trials for MM; however, its activity as a single agent was limited to myeloma patients with the t(11;14) translocation who acquire resistance due to co-expression of Mcl-1 and Bcl-xL. These limitations preclude its use in a broader patient population. We have recently found that a sphingosine kinase 2-specific inhibitor (ABC294640) induces apoptosis in primary human CD138+ cells and MM cell lines. ABC294640 is currently in phase I/II clinical trials for myeloma (clinicaltrials.gov: #NCT01410981). Interestingly, ABC294640 down-regulates c-Myc and Mcl-1, but does not have any effects on Bcl-2. We first evaluated the combinatorial anti-myeloma effect of ABC294640 and ABT-199 in vitro in 7 MM cell lines, all of which harbor no t(11;14) translocation. Combination index calculation demonstrated a synergistic anti-myeloma effect of the combination of ABC294640 and ABT-199. This synergistic anti-myeloma effect was maintained even in the presence of bone marrow (BM) stromal cells. The combination of ABC294640 and ABT-199 led to enhanced cleavage of PARP and caspase-3/9 and increased Annexin-V expression, consistent with the induction of apoptosis by the combination treatment. In addition, the combination of ABC294640 and ABT-199 resulted in the down-regulation of the anti-apoptotic proteins Mcl-1, Bcl-2, and Bcl-xL and the cleavage of Bax and Bid. The combination induced both the mitochondrial mediated- and caspase-mediated apoptosis pathways. Finally, the combination of ABC294640 and ABT-199 resulted in augmented anti-myeloma effect in vivo in a mouse xenograft model. These findings demonstrate that the co-administration of ABC294640 and ABT-199 exhibits synergistic anti-myeloma activity in vitro and in vivo, providing justification for a clinical study of this novel combination in patients with relapsed/refractory multiple myeloma.

Dataset Information

Antiestrogenic effects of the novel sphingosine kinase-2 inhibitor ABC294640.

Publications

Antiestrogenic effects of the novel sphingosine kinase-2 inhibitor ABC294640.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets