Cytotoxic synergy between the multikinase inhibitor sorafenib and the proteasome inhibitor bortezomib in vitro: Induction of apoptosis through Akt and c-Jun NH2-terminal kinase pathways

Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA.
Molecular Cancer Therapeutics (Impact Factor: 6.11). 10/2006; 5(9):2378-87. DOI: 10.1158/1535-7163.MCT-06-0235
Source: PubMed

ABSTRACT This study was undertaken to characterize preclinical cytotoxic interactions for human malignancies between the multikinase inhibitor sorafenib (BAY 43-9006) and proteasome inhibitors bortezomib or MG132. Multiple tumor cell lines of varying histiotypes, including A549 (lung adenocarcinoma), 786-O (renal cell carcinoma), HeLa (cervical carcinoma), MDA-MB-231 (breast), K562 (chronic myelogenous leukemia), Jurkat (acute T-cell leukemia), MEC-2 (B-chronic lymphocytic leukemia), and U251 and D37 (glioma), as well as cells derived from primary human glioma tumors that are likely a more clinically relevant model were treated with sorafenib or bortezomib alone or in combination. Sorafenib and bortezomib synergistically induced a marked increase in mitochondrial injury and apoptosis, reflected by cytochrome c release, caspase-3 cleavage, and poly(ADP-ribose) polymerase degradation in a broad range of solid tumor and leukemia cell lines. These findings were accompanied by several biochemical changes, including decreased phosphorylation of vascular endothelial growth factor receptor-2, platelet-derived growth factor receptor-beta, and Akt and increased phosphorylation of stress-related c-Jun NH2-terminal kinase (JNK). Inhibition of Akt was required for synergism, as a constitutively active Akt protected cells against apoptosis induced by the combination. Alternatively, the JNK inhibitor SP600125 could also protect cells from apoptosis induced by the combination, indicating that both inhibition of Akt and activation of JNK were required for the synergism. These findings show that sorafenib interacts synergistically with bortezomib to induce apoptosis in a broad spectrum of neoplastic cell lines and show an important role for the Akt and JNK pathways in mediating synergism. Further clinical development of this combination seems warranted.

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    • "Among these, sorafenib seems to have a pivotal role. It has been demonstrated in various tumour cell lines that sorafenib induced mitochondrial damage manifested by cytochrome c release into the cytosol, caspase 9 and 3 activation, and in consequence , apoptosis mediated through an intrinsic pathway (Huang et al. 2010; Rahmani et al. 2007; Yu et al. 2006). On the other hand, other experiments showed that apoptosis after sorafenib treatment was correlated with an external pathway with caspase 8 activation (Park et al. 2010). "
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    ABSTRACT: The aim of the present study was to investigate the effect of sorafenib and quercetin on the induction of apoptosis and autophagy in human anaplastic astrocytoma (MOGGCCM) and glioblastoma multiforme (T98G) cell lines. In MOGGCCM cells, sorafenib initiated mainly apoptosis, mediated by the mitochondrial pathway with mitochondrial membrane permeabilization, cytochrome c release to the cytoplasm, and activation of caspase 9 and 3. Additional incubation with quercetin potentiated the pro-apoptotic properties of sorafenib. In T98G cells, autophagy was observed most frequently after the sorafenib treatment. It was accompanied by increased beclin 1 and LC3II expression. Administration of quercetin after the sorafenib treatment resulted in an increased number of autophagic cells. After simultaneous drug application, the level of autophagy was lower in favour of apoptosis. Inhibition of heat shock proteins expression by specific small interfering RNA significantly increased the sensitivity of both the cell lines to induction of apoptosis, but not autophagy. We demonstrated for the first time that sorafenib and quercetin are very effective programmed cell death inducers in T98G and MOGGCCM cells, especially in cells with blocked expression of heat shock proteins.
    Neurotoxicity Research 12/2013; 26(1). DOI:10.1007/s12640-013-9452-x · 3.15 Impact Factor
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    • "In our recent studies, we demonstrated that bortezomib exhibited significant activity against proliferation in glioma cells and sensitized highly resistant glioma cells to TRAIL (Jane et al., 2011) or HDACI-induced cytotoxicity (Premkumar et al., 2011). Because several members of the Bcl-2 family (Yu et al., 2008; Premkumar et al., 2011), Akt (Yu et al., 2006) and NF-␬B (Jane et al., 2011), are known targets of bortezomib in glioma, we investigated the combination of bortezomib and ABT-737 to assess sensitivity in vitro. The combination of ABT-737 and bortezomib strongly induced apoptosis and activated caspase-3 and PARP, and to a lesser extent, caspase-8 and caspase-9 (data not shown), relative to untreated control cells in ABT-737- Fig. 1. "
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    ABSTRACT: We observed that glioma cells are differentially sensitive to N-{4-[4-(4'-chloro-biphenyl-2-ylmethyl)-piperazin-1-yl]-benzoyl}-4-(3-dimethylamino-1-phenylsulfanylmethyl-propylamino)-3-nitro-benzenesulfonamide (ABT-737) and administration of ABT-737 at clinically achievable doses failed to induce apoptosis. Although elevated Bcl-2 levels directly correlated with sensitivity to ABT-737, overexpression of Bcl-2 did not influence sensitivity to ABT-737. To understand the molecular basis for variable and relatively modest sensitivity to the Bcl-2 homology domain 3 mimetic drug ABT-737, the abundance of Bcl-2 family members was assayed in a panel of glioma cell lines. Bcl-2 family member proteins, Bcl-xL, Bcl-w, Mcl-1, Bax, Bak, Bid, and Noxa, were found to be expressed ubiquitously at similar levels in all cell lines tested. We then examined the contribution of other apoptosis-resistance pathways to ABT-737 resistance. Bortezomib, an inhibitor of nuclear factor-kappaB (NF-κB), was found to enhance sensitivity of ABT-737 in phosphatase and tensin homolog on chromosome 10 (PTEN)-wild type, but not PTEN-mutated glioma cell lines. We therefore investigated the association between phosphatidylinositol 3-kinase (PI3K)/Akt activation and resistance to the combination of ABT-737 and bortezomib in PTEN-deficient glioma cells. Genetic and pharmacological inhibition of PI3K inhibition sensitized PTEN-deficient glioma cells to bortezomib- and ABT-737-induced apoptosis by increasing cleavage of Bid protein, activation and oligomerization of Bax, and loss of mitochondrial membrane potential. Our data further suggested that PI3K/Akt-dependent protection may occur upstream of the mitochondria. This study demonstrates that interference with multiple apoptosis-resistance signaling nodes, including NF-κB, Akt, and Bcl-2, may be required to induce apoptosis in highly resistant glioma cells, and therapeutic strategies that target the PI3K/Akt pathway may have a selective role for cancers lacking PTEN function.
    Journal of Pharmacology and Experimental Therapeutics 03/2012; 341(3):859-72. DOI:10.1124/jpet.112.191536 · 3.86 Impact Factor
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    • "Furthermore, in the context of Epstein-Barr virus-associated lymphoma cells, MAPK14 pathway inhibition induced apoptosis and prevented virus replication upon induction (Reinhardt et al, 2007; Matusali et al, 2009). We hypothesize that MAPK14 phosphorylation status may represent a surrogate marker of sorafenib bioactivity in lymphoma, and that the pro-apoptotic effects of sorafenib in lymphoma cells may be potentiated by other inducers of tumour cell apoptosis used in combination, as shown for acute myeloid leukaemia and medullobastoma (Yu et al, 2006; Zhang et al, 2008b). Notably, our in vitro studies addressed direct effects of sorafenib on lymphoma cell biology only, whereas in vivo, further tumour inhibition may be achieved by angiostatic effects in the tumour microenvironment (Wilhelm et al, 2004). "
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    ABSTRACT: Intracellular signal transduction by kinase-mediated phosphorylation is essential for the survival and growth of lymphoma cells. This study analysed the multikinase inhibitor sorafenib for its cytotoxic activity against lymphoma cells. We found that sorafenib reduced cell viability at low micromolar concentrations in a time-dependent manner in cell lines and primary cell suspensions representing major types of aggressive B- and T-cell lymphomas. In cells surviving short term exposure, proliferative arrest occurred leading to complete loss of in vitro clonogenicity. Previously described sorafenib targets within the RAF kinase family were found to be expressed and phosphorylated in all cell lines, and sorafenib perturbed the activation of classical RAF/MEK/ERK pathway targets. However, using a global phoshoprotein array, the most consistent downstream effect of sorafenib in NHL cells was the inhibition of mitogen-activated protein kinase 14 (MAPK14) and panAKT phosphorylation. In conclusion, sorafenib has significant in vitro efficacy against aggressive B- and T-cell lymphoma cells, associated with inhibition of MAPK14 and panAKT.
    British Journal of Haematology 02/2011; 152(4):401-12. DOI:10.1111/j.1365-2141.2010.08526.x · 4.96 Impact Factor
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