In:
Clinical Cancer Research, American Association for Cancer Research (AACR), Vol. 14, No. 14 ( 2008-07-15), p. 4640-4649
Abstract:
Purpose: Statins are pharmacologic inhibitors of the 3-hydroxy-3-methylglutaryl-coenzyme A reductase with potent regulatory effects on cholesterol biosynthesis in vitro and in vivo. There is accumulating evidence that, beyond their cholesterol-lowering properties, statins inhibit cell proliferation and promote apoptosis of malignant cells in vitro, but the mechanisms by which they generate such responses remain to be defined. Experimental Design: Combinations of experimental approaches were used, including immunoblotting and cell proliferation and apoptosis assays. Results: We provide evidence that fluvastatin is a potent inducer of apoptosis and suppresses proliferation of renal cell carcinoma (RCC) cells in vitro. Such effects are mediated by direct targeting of the Akt/mammalian target of rapamycin (mTOR) pathway, as evidenced by the suppression of phosphorylation/activation of Akt, resulting in inhibition of its downstream effectors, mTOR and p70 S6 kinase. In addition, fluvastatin blocks the mTOR-dependent phosphorylation/deactivation of the translational repressor eukaryotic initiation factor 4E (eIF4E)-binding protein, leading to the formation of eIF4E-binding protein-eIF4E complexes that suppress initiation of cap-dependent mRNA translation. Importantly, inhibition of p70 S6 kinase activity by fluvastatin results in the up-regulation of expression of programmed cell death 4 (PDCD4), a tumor suppressor protein with inhibitory effects on the translation initiation factor eIF4A, suggesting a mechanism for the generation of antitumor responses. Conclusions: Altogether, our findings establish that fluvastatin exhibits potent anti-RCC activities via inhibitory effects on the Akt/mTOR pathway and raise the possibility that combinations of statins and Akt inhibitors may be of future therapeutic value in the treatment of RCC.
Type of Medium:
Online Resource
ISSN:
1078-0432
,
1557-3265
DOI:
10.1158/1078-0432.CCR-07-5232
Language:
English
Publisher:
American Association for Cancer Research (AACR)
Publication Date:
2008
detail.hit.zdb_id:
1225457-5
detail.hit.zdb_id:
2036787-9
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