TY - JOUR
T1 - Simvastatin potentiates TNF-α-induced apoptosis through the down-regulation of NF-κB-dependent antiapoptotic gene products
T2 - Role of IκBα kinase and TGF-β-activated kinase-1
AU - Kwang, Seok Ahn
AU - Sethi, Gautam
AU - Aggarwal, Bharat B.
PY - 2007/2/15
Y1 - 2007/2/15
N2 - Numerous recent reports suggest that statins (hydroxy-3-methylglutaryl-CoA reductase inhibitors) exhibit potential to suppress tumorigenesis through a mechanism that is not fully understood. Therefore, in this article, we investigated the effects of simvastatin on TNF-α-induced cell signaling. We found that simvastatin potentiated the apoptosis induced by TNF-α as indicated by intracellular esterase activity, caspase activation, TUNEL, and annexin V staining. This effect of simvastatin correlated with downregulation of various gene products that mediate cell proliferation (cyclin D1 and cyclooxygenase-2), cell survival (Bcl-2, Bcl-xL, cellular FLIP, inhibitor of apoptosis protein 1, inhibitor of apoptosis protein 2, and survivin), invasion (matrix mellatoproteinase-9 and ICAM-1), and angiogenesis (vascular endothelial growth factor); all known to be regulated by the NF-κB. We found that simvastatin inhibited TNF-α-induced NF-κB activation, and L-mevalonate reversed the suppressive effect, indicating the role of hydroxy-3-methylglutaryl-CoA reductase. Simvastatin suppressed not only the inducible but also the constitutive NF-κB activation. Simvastatin inhibited TNF-α-induced IκBα kinase activation, which led to inhibition of IκBα phosphorylation and degradation, suppression of p65 phosphorylation, and translocation to the nucleus. NF-κB-dependent reporter gene expression induced by TNF-α, TNFR1, TNFR-associated death domain protein, TNFR-associated factor 2, TGF-β-activated kinase 1, receptor-interacting protein, NF-κB-inducing kinase, and IκB kinase β was abolished by simvastatin. Overall, our results provide novel insight into the role of simvastatin in potentially preventing and treating cancer through modulation of IκB kinase and NF-κB-regulated gene products.
AB - Numerous recent reports suggest that statins (hydroxy-3-methylglutaryl-CoA reductase inhibitors) exhibit potential to suppress tumorigenesis through a mechanism that is not fully understood. Therefore, in this article, we investigated the effects of simvastatin on TNF-α-induced cell signaling. We found that simvastatin potentiated the apoptosis induced by TNF-α as indicated by intracellular esterase activity, caspase activation, TUNEL, and annexin V staining. This effect of simvastatin correlated with downregulation of various gene products that mediate cell proliferation (cyclin D1 and cyclooxygenase-2), cell survival (Bcl-2, Bcl-xL, cellular FLIP, inhibitor of apoptosis protein 1, inhibitor of apoptosis protein 2, and survivin), invasion (matrix mellatoproteinase-9 and ICAM-1), and angiogenesis (vascular endothelial growth factor); all known to be regulated by the NF-κB. We found that simvastatin inhibited TNF-α-induced NF-κB activation, and L-mevalonate reversed the suppressive effect, indicating the role of hydroxy-3-methylglutaryl-CoA reductase. Simvastatin suppressed not only the inducible but also the constitutive NF-κB activation. Simvastatin inhibited TNF-α-induced IκBα kinase activation, which led to inhibition of IκBα phosphorylation and degradation, suppression of p65 phosphorylation, and translocation to the nucleus. NF-κB-dependent reporter gene expression induced by TNF-α, TNFR1, TNFR-associated death domain protein, TNFR-associated factor 2, TGF-β-activated kinase 1, receptor-interacting protein, NF-κB-inducing kinase, and IκB kinase β was abolished by simvastatin. Overall, our results provide novel insight into the role of simvastatin in potentially preventing and treating cancer through modulation of IκB kinase and NF-κB-regulated gene products.
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U2 - 10.4049/jimmunol.178.4.2507
DO - 10.4049/jimmunol.178.4.2507
M3 - Article
C2 - 17277159
AN - SCOPUS:33846896918
SN - 0022-1767
VL - 178
SP - 2507
EP - 2516
JO - Journal of Immunology
JF - Journal of Immunology
IS - 4
ER -