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ABSTRACT: PURPOSE: The TORC1 inhibitor everolimus has previously shown significant activity as a single agent in hematologic malignancies, with reported responses of 30-70% in Waldenstrom Macroglobulinemia (WM). However, the specific mechanisms by which this class of mTOR inhibitors exerts anti-WM activity has not been fully investigated. We therefore sought to dissect the mechanisms of everolimus-dependent modulation of WM cell survival. EXPERIMENTAL DESIGN: We confirmed that everolimus targets mTOR in patients treated with everolimus and responding to therapy. We evaluated the effect of everolimus on proliferation and survival of primary WM cells, as well as of other IgM-secreting lymphoma cell lines. Everolimus-dependent mechanisms of induced apoptosis, and its effect on WM cells in the context of bone marrow microenvironment have been also evaluated. miRNA-155 loss-of function studies were performed. Moreover, the combinatory effect of bortezomib and rituximab has been tested. RESULTS: We demonstrated that everolimus targeted mTOR-downstream signaling pathways, ex vivo, in patients responding to everolimus treatment. Everolimus induced toxicity in primary WM cells, as well as in other IgM-secreting lymphoma cells, supported by cell cycle arrest, caspase-dependent and -independent induction of apoptosis. Importantly, everolimus targeted WM cells even in the context of bone marrow milieu, where it affected migration, adhesion and angiogenesis. Everolimus-dependent anti-WM activity was partially driven by microRNA155. Moreover, everolimus synergized with bortezomib and rituximab in targeting WM cells, as shown by synergistic inhibition of p65- and p50-NFkB activities. CONCLUSIONS: These findings provide a better understanding of the mechanisms that are responsible for everolimus-induced anti-WM activity.
Clinical Cancer Research 10/2012; · 7.74 Impact Factor
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ABSTRACT: Waldenström macroglobulinemia (WM) cells present with increased expression of microRNA-206 (miRNA-206) and reduced expression of miRNA-9*. Predicted miRNA-206- and -9*-targeted genes include histone deacetylases (HDACs) and histone acetyl transferases (HATs), indicating that these miRNAs may play a role in regulating histone acetylation. We were able to demonstrate that primary WM cells are characterized by unbalanced expression of HDACs and HATs, responsible for decreased acetylated histone-H3 and -H4, and increased HDAC activity. We next examined whether miRNA-206 and -9* modulate the aberrant expression of HDAC and HATs in WM cells leading to increased transcriptional activity. We found that restoring miRNA-9* levels induced toxicity in WM cells, supported by down-modulation of HDAC4 and HDAC5 and up-regulation of acetyl-histone-H3 and -H4. These, together with inhibited HDAC activity, led to induction of apoptosis and autophagy in WM cells. To further confirm that miRNA-9*-dependent modulation of histone acetylation is responsible for induction of WM cytotoxicity, a novel class of HDAC inhibitor (LBH589) was used; we confirmed that inhibition of HDAC activity leads to toxicity in this disease. These findings confirm that histone-modifying genes and HDAC activity are deregulated in WM cells, partially driven by the aberrant expression of miRNA-206 and -9* in the tumor clone.
Blood 09/2010; 116(9):1506-14. · 9.90 Impact Factor
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Irene M Ghobrial,
Aldo Roccaro,
Fangxin Hong,
Edie Weller,
Nancy Rubin,
Renee Leduc,
Meghan Rourke,
Stacey Chuma,
Antonio Sacco, Xiaoying Jia,
Feda Azab,
Abdel Kareem Azab,
Scott Rodig,
Diane Warren,
Brianna Harris,
Lyuba Varticovski,
Peter Sportelli,
Xavier Leleu,
Kenneth C Anderson,
Paul G Richardson
[show abstract]
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ABSTRACT: Waldenström's macroglobulinemia (WM) is a rare, low-grade lymphoproliferative disorder. Based on preclinical studies, we conducted a phase II clinical trial testing the efficacy and safety of the Akt inhibitor perifosine in patients with relapsed/refractory WM.
Thirty-seven patients were treated with oral perifosine (150 mg daily) for six cycles. Stable or responding patients were allowed to continue therapy until progression.
The median age was 65 years (range, 44-82). The median number of prior therapy lines was two (range, one to five). Of the 37 patients, 4 achieved partial response (11%), 9 minimal response (24%), and 20 showed stable disease (54%). The median progression-free survival was 12.6 months. Additionally, beta2 microglobulin of >3.5 mg/dL was associated with poor event-free survival (P = 0.002). Perifosine was generally well tolerated; adverse events related to therapy were cytopenias (grade 3-4, 13%), gastrointestinal symptoms (grade 1-2, 81%), and arthritis flare (all grades, 11%). Translational studies using gene expression profiling and immunohistochemistry showed that perifosine inhibited pGSK activity downstream of Akt, and inhibited nuclear factor kappaB activity.
Perifosine resulted in at least a minimal response in 35% of patients and a median progression-free survival of 12.6 months in patients with relapsed or relapsed/refractory WM, as well as in vivo inhibition of pGSK activity. The results of this study warrant further evaluation of perifosine in combination with rituximab or other active agents in patients with WM.
Clinical Cancer Research 02/2010; 16(3):1033-41. · 7.74 Impact Factor
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Hai T Ngo,
Abdel Kareem Azab,
Mena Farag, Xiaoying Jia,
Molly M Melhem,
Judith Runnels,
Aldo M Roccaro,
Feda Azab,
Antonio Sacco,
Xavier Leleu,
Kenneth C Anderson,
Irene M Ghobrial
[show abstract]
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ABSTRACT: Waldenstrom macroglobulinemia is a lymphoplasmacytic lymphoma characterized by widespread involvement of the bone marrow. Despite different options of therapy, Waldenstrom macroglobulinemia is still incurable. Src tyrosine kinase has been shown to play a central role in the regulation of a variety of biological processes, such as cell proliferation, migration, adhesion, and survival in solid tumors. We sought to determine whether the protein tyrosine kinase Src regulates adhesion, migration, and survival in Waldenstrom macroglobulinemia.
We tested the expression of Src tyrosine kinase in Waldenstrom macroglobulinemia and normal cells, and the effect of the specific Src inhibitor AZD0530 on the adhesion, migration, cell cycle, and survival of a Waldenstrom macroglobulinemia cell line and patient samples. Moreover, we tested the effect of AZD0530 on cytoskeletal and cell cycle signaling in Waldenstrom macroglobulinemia.
We show that Src is overexpressed in Waldenstrom macroglobulinemia cells compared with control B cells, and that the use of the Src inhibitor AZD0530 led to significant inhibition of adhesion, migration, and cytoskeletal signaling induced by SDF1. Moreover, inhibition of Src activity induced G(1) cell cycle arrest; however, it had minimal effect on survival of Waldenstrom macroglobulinemia cells, and no significant effect on survival of normal cells.
Taken together, these results delineate the role of Src kinase activity in Waldenstrom macroglobulinemia and provide the framework for future clinical trials using Src inhibitors in combination with other drugs to improve the outcome of patients with Waldenstrom macroglobulinemia.
Clinical Cancer Research 09/2009; 15(19):6035-41. · 7.74 Impact Factor
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Abdel Kareem Azab,
Feda Azab,
Simona Blotta,
Costas M Pitsillides,
Brian Thompson,
Judith M Runnels,
Aldo M Roccaro,
Hai T Ngo,
Molly R Melhem,
Antonio Sacco, Xiaoying Jia,
Kenneth C Anderson,
Charles P Lin,
Barrett J Rollins,
Irene M Ghobrial
[show abstract]
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ABSTRACT: The interaction of multiple myeloma (MM) cells with the bone marrow (BM) milieu plays a crucial role in MM pathogenesis. Stromal cell-derived factor-1 (SDF1) regulates homing of MM cells to the BM. In this study, we examined the role of RhoA and Rac1 GTPases in SDF1-induced adhesion and chemotaxis of MM. We found that both RhoA and Rac1 play key roles in SDF1-induced adhesion of MM cells to BM stromal cells, whereas RhoA was involved in chemotaxis and motility. Furthermore, both ROCK and Rac1 inhibitors reduced SDF1-induced polymerization of actin and activation of LIMK, SRC, FAK, and cofilin. Moreover, RhoA and Rac1 reduced homing of MM cells to BM niches. In conclusion, we characterized the role of RhoA and Rac1 GTPases in SDF1-induced adhesion, chemotaxis, and homing of MM cells to the BM, providing the framework for targeting RhoA and Rac1 GTPases as novel MM therapy.
Blood 06/2009; 114(3):619-29. · 9.90 Impact Factor
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Aldo M Roccaro,
Antonio Sacco,
Brian Thompson,
Xavier Leleu,
Abdel Kareem Azab,
Feda Azab,
Judith Runnels, Xiaoying Jia,
Hai T Ngo,
Molly R Melhem,
Charles P Lin,
Domenico Ribatti,
Barrett J Rollins,
Thomas E Witzig,
Kenneth C Anderson,
Irene M Ghobrial
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ABSTRACT: Detailed genomic studies have shown that cytogenetic abnormalities contribute to multiple myeloma (MM) pathogenesis and disease progression. Nevertheless, little is known about the characteristics of MM at the epigenetic level and specifically how microRNAs regulate MM progression in the context of the bone marrow milieu. Therefore, we performed microRNA expression profiling of bone marrow derived CD138(+) MM cells versus their normal cellular counterparts and validated data by qRT-PCR. We identified a MM-specific microRNA signature characterized by down-expression of microRNA-15a/-16 and overexpression of microRNA-222/-221/-382/-181a/-181b (P < .01). We investigated the functional role of microRNA-15a and -16 and showed that they regulate proliferation and growth of MM cells in vitro and in vivo by inhibiting AKT serine/threonine-protein-kinase (AKT3), ribosomal-protein-S6, MAP-kinases, and NF-kappaB-activator MAP3KIP3. Moreover, miRNA-15a and -16 exerted their anti-MM activity even in the context of the bone marrow milieu in vitro and in vivo. These data indicate that microRNAs play a pivotal role in the biology of MM and represent important targets for novel therapies in MM.
Blood 05/2009; 113(26):6669-80. · 9.90 Impact Factor
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Irene M Ghobrial,
Xavier Leleu,
Abdel Kareem Azab,
Judith Runnels, Xiaoying Jia,
Hai Ngo,
Molly Melhem,
Feda Azab,
Antonio Sacco,
Phong Quang,
Nicholas Burwick,
Anne-Sophie Moreau,
Emanuel Husu,
Mena Farag,
Aldo Roccaro
[show abstract]
[hide abstract]
ABSTRACT: Within the past few years, major advances in the preclinical and clinical testing of novel therapeutic agents have occurred in Waldenström's macroglobulinemia (WM). These include agents that target the PI3K/Akt/mTOR pathway, PKC pathways, NF-kB signaling pathway, as well as tyrosine kinases and histone deacetylase inhibitors. In this review, we summarize the current understanding of the clinical development of these agents in WM.
Clinical Lymphoma & Myeloma 03/2009; 9(1):84-6. · 1.13 Impact Factor
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Aldo M Roccaro,
Antonio Sacco,
Xavier Leleu,
Abdel Kareem Azab,
Feda Azab,
Judith Runnels, Xiaoying Jia,
Hai T Ngo,
Molly Melhem,
Anne-Sophie Moreau,
Irene M Ghobrial
[show abstract]
[hide abstract]
ABSTRACT: The paradigm for the treatment of monoclonal gammophaties has dramatically changed: based on the understanding of the complex interaction between tumor cells and bone marrow microenvironment and the signaling pathways that are deregulated in this process, a number of novel therapeutic agents are now available. For example, 3 novel agents with a targeted anti-multiple myeloma activity, have been FDA approved for the treatment of this disease, namely bortezomib, thalidomide, and lenalidomide. The success of targeted therapy in myeloma has led to the development and investigation of more than 30 new compounds in this disease and in other plasma cell dyscrasias such as Waldenström's macroglobulinemia (WM), both in the preclinical settings and as part of clinical trials. Among them the role of proteasome inhibitors has been widely dissected providing the preclinical basis for clinical trials of combinations of proteasome inhibitors in WM.
Clinical Lymphoma & Myeloma 03/2009; 9(1):94-6. · 1.13 Impact Factor
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Abdel Kareem Azab,
Judith M Runnels,
Costas Pitsillides,
Anne-Sophie Moreau,
Feda Azab,
Xavier Leleu, Xiaoying Jia,
Renee Wright,
Beatriz Ospina,
Alicia L Carlson, [......],
Mena Farag,
Molly R Melhem,
Antonio Sacco,
Nikhil C Munshi,
Teru Hideshima,
Barrett J Rollins,
Kenneth C Anderson,
Andrew L Kung,
Charles P Lin,
Irene M Ghobrial
[show abstract]
[hide abstract]
ABSTRACT: The interaction of multiple myeloma (MM) cells with their microenvironment in the bone marrow (BM) provides a protective environment and resistance to therapeutic agents. We hypothesized that disruption of the interaction of MM cells with their BM milieu would lead to their sensitization to therapeutic agents such as bortezomib, melphalan, doxorubicin, and dexamethasone. We report that the CXCR4 inhibitor AMD3100 induces disruption of the interaction of MM cells with the BM reflected by mobilization of MM cells into the circulation in vivo, with kinetics that differed from that of hematopoietic stem cells. AMD3100 enhanced sensitivity of MM cell to multiple therapeutic agents in vitro by disrupting adhesion of MM cells to bone marrow stromal cells (BMSCs). Moreover, AMD3100 increased mobilization of MM cells to the circulation in vivo, increased the ratio of apoptotic circulating MM cells, and enhanced the tumor reduction induced by bortezomib. Mechanistically, AMD3100 significantly inhibited Akt phosphorylation and enhanced poly(ADP-ribose) polymerase (PARP) cleavage as a result of bortezomib, in the presence of BMSCs in coculture. These experiments provide a proof of concept for the use of agents that disrupt interaction with the microenvironment for enhancement of efficacy of cytotoxic agents in cancer therapy.
Blood 02/2009; 113(18):4341-51. · 9.90 Impact Factor
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Aldo M Roccaro,
Antonio Sacco,
Changzhong Chen,
Judith Runnels,
Xavier Leleu,
Feda Azab,
Abdel Kareem Azab, Xiaoying Jia,
Hai T Ngo,
Molly R Melhem,
Nicholas Burwick,
Lyuba Varticovski,
Carl D Novina,
Barrett J Rollins,
Kenneth C Anderson,
Irene M Ghobrial
[show abstract]
[hide abstract]
ABSTRACT: Multilevel genetic characterization of Waldenström macroglobulinemia (WM) is required to improve our understanding of the underlying molecular changes that lead to the initiation and progression of this disease. We performed microRNA-expression profiling of bone marrow-derived CD19(+) WM cells, compared with their normal cellular counterparts and validated data by quantitative reverse-transcription-polymerase chain reaction (qRT-PCR). We identified a WM-specific microRNA signature characterized by increased expression of microRNA-363*/-206/-494/-155/-184/-542-3p, and decreased expression of microRNA-9* (ANOVA; P < .01). We found that microRNA-155 regulates proliferation and growth of WM cells in vitro and in vivo, by inhibiting MAPK/ERK, PI3/AKT, and NF-kappaB pathways. Potential microRNA-155 target genes were identified using gene-expression profiling and included genes involved in cell-cycle progression, adhesion, and migration. Importantly, increased expression of the 6 miRNAs significantly correlated with a poorer outcome predicted by the International Prognostic Staging System for WM. We further demonstrated that therapeutic agents commonly used in WM alter the levels of the major miRNAs identified, by inducing downmodulation of 5 increased miRNAs and up-modulation of patient-downexpressed miRNA-9*. These data indicate that microRNAs play a pivotal role in the biology of WM; represent important prognostic marker; and provide the basis for the development of new microRNA-based targeted therapies in WM.
Blood 12/2008; 113(18):4391-402. · 9.90 Impact Factor
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Xavier Leleu,
Lian Xu, Xiaoying Jia,
Antonio Sacco,
Mena Farag,
Zachary R Hunter,
Anne-Sophie Moreau,
Hai T Ngo,
Evdoxia Hatjiharissi,
Allen W Ho,
Daniel D Santos,
Sofia Adamia,
Kelly O'Connor,
Bryan Ciccarelli,
Jacob Soumerai,
Robert J Manning,
Christopher J Patterson,
Aldo M Roccaro,
Irene M Ghobrial,
Steven P Treon
[show abstract]
[hide abstract]
ABSTRACT: Waldenstrom macroglobulinemia (WM) is an incurable low-grade lymphoma characterized by bone marrow (BM) involvement of IgM secreting lymphoplasmacytic cells. The induction of unfolded protein response (UPR) genes ("physiologic" UPR) enables cells to differentiate into professional secretory cells capable of production of high amounts of endoplasmic reticulum (ER)-processed proteins, such as immunoglobulins. Ultimately, the initially cytoprotective UPR triggers an apoptotic cascade if ER stress is not corrected, called proapoptotic/terminal UPR. We show that WM cells inherently express the physiologic UPR machinery compared with normal BM cells, and that increased ER stress leads to proapoptotic/terminal UPR in WM cells. We therefore examined tunicamycin, ER stress inducer, for potential antitumor effects in WM. Tunicamycin induced significant cytotoxicity, apoptosis and cell-cycle arrest, and inhibited DNA synthesis in WM cell lines and primary BM CD19(+) cells from patients with WM with an inhibitory concentration (IC(50)) of 0.5 microg/mL to 1 microg/mL, but not in healthy donor cells. Importantly, coculture of WM cells in the context of the BM microenvironment did not inhibit tunicamycin-induced cytotoxicity. Finally, we demonstrate that ER stress inducer synergizes with other agents used in the treatment of WM. These preclinical studies provide a framework for further evaluation of ER stress inducing agents as therapeutic agents in WM.
Blood 12/2008; 113(3):626-34. · 9.90 Impact Factor
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Anne-Sophie Moreau, Xiaoying Jia,
Christopher J. Patterson,
Aldo M. Roccaro,
Lian Xu,
Antonio Sacco,
Kelly O’Connor,
Jacob Soumerai,
Hai T. Ngo,
Evdoxia Hatjiharissi,
Zachary R. Hunter,
Bryan Ciccarelli,
Robert Manning,
Irene M. Ghobrial,
Xavier Leleu,
Steven P. Treon
[show abstract]
[hide abstract]
ABSTRACT: Waldenstrom macroglobulinaemia (WM) is an incurable lymphoplasmacytic lymphoma with secretion of serum monoclonal immunoglobulin M (IgM). We previously showed that patients receiving cholesterol-lowering statins, had the lowest IgM value in a large cohort of patients with WM. Simvastatin, a 3-hydroxy-3-methyl-glutaryl-CoA reductase inhibitor, induced inhibition of proliferation, cytotoxic effect and apoptosis in IgM secreting cell lines as well as in primary CD19+ WM cells. Interestingly, those effects were reversed by addition of mevalonate and geranylgeranylpyrophosphate, demonstrating that simvastatin inhibited cell growth, survival and IgM secretion on BCWM.1 WM cells by inhibition of geranylgeranylated proteins. Furthermore, simvastatin overcame tumour cell growth induced by co-culture of WM cells with bone-marrow stromal cells. Simvastatin also decreased IgM secretion by BCWM.1 cells at an early time-point that had not affected cell survival. Simvastatin-induced cytotoxicity was preceded by a decrease in Akt (protein kinase B, PKB) and extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase (MAPK) pathways at 18 h. In addition, simvastatin induced an increase in stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) MAPK followed by caspase-8, -9, -3 and poly(ADP-ribose) polymerase (PARP) cleavages at 18 h, leading to apoptosis. Furthermore, simvastatin enhanced the cytotoxicity induced by bortezomib, fludarabine and dexamethasone. Our studies therefore support our earlier observation of statin-mediated anti-WM activity and provide the framework for future clinical trials testing simvastatin in WM.
British Journal of Haematology 08/2008; 142(5):775 - 785. · 4.94 Impact Factor
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Hai T Ngo,
Xavier Leleu,
Jack Lee, Xiaoying Jia,
Molly Melhem,
Judith Runnels,
Anne-Sophie Moreau,
Nicholas Burwick,
Abdel Kareem Azab,
Aldo Roccaro,
Feda Azab,
Antonio Sacco,
Mena Farag,
Robert Sackstein,
Irene M Ghobrial
[show abstract]
[hide abstract]
ABSTRACT: Waldenstrom macroglobulinemia (WM) is characterized by widespread involvement of the bone marrow at the time of diagnosis, implying continuous homing of WM cells into the marrow. The mechanisms by which trafficking of the malignant cells into the bone marrow has not been previously elucidated. In this study, we show that WM cells express high levels of chemokine and adhesion receptors, including CXCR4 and VLA-4. We showed that CXCR4 was essential for the migration and trans-endothelial migration of WM cells under static and dynamic shear flow conditions, with significant inhibition of migration using CXCR4 knockdown or the CXCR4 inhibitor AMD3100. Similarly, CXCR4 or VLA-4 inhibition led to significant inhibition of adhesion to fibronectin, stromal cells, and endothelial cells. Decreased adhesion of WM cells to stromal cells by AMD3100 led to increased sensitivity of these cells to cytotoxicity by bortezomib. To further investigate the mechanisms of CXCR4-dependent adhesion, we showed that CXCR4 and VLA-4 directly interact in response to SDF-1, we further investigated downstream signaling pathways regulating migration and adhesion in WM. Together, these studies demonstrate that the CXCR4/SDF-1 axis interacts with VLA-4 in regulating migration and adhesion of WM cells in the bone marrow microenvironment.
Blood 08/2008; 112(1):150-8. · 9.90 Impact Factor
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Anne-Sophie Moreau, Xiaoying Jia,
Christopher J Patterson,
Aldo M Roccaro,
Lian Xu,
Antonio Sacco,
Kelly O'Connor,
Jacob Soumerai,
Hai T Ngo,
Evdoxia Hatjiharissi,
Zachary R Hunter,
Bryan Ciccarelli,
Robert Manning,
Irene M Ghobrial,
Xavier Leleu,
Steven P Treon
[show abstract]
[hide abstract]
ABSTRACT: Waldenstrom macroglobulinaemia (WM) is an incurable lymphoplasmacytic lymphoma with secretion of serum monoclonal immunoglobulin M (IgM). We previously showed that patients receiving cholesterol-lowering statins, had the lowest IgM value in a large cohort of patients with WM. Simvastatin, a 3-hydroxy-3-methyl-glutaryl-CoA reductase inhibitor, induced inhibition of proliferation, cytotoxic effect and apoptosis in IgM secreting cell lines as well as in primary CD19(+) WM cells. Interestingly, those effects were reversed by addition of mevalonate and geranylgeranylpyrophosphate, demonstrating that simvastatin inhibited cell growth, survival and IgM secretion on BCWM.1 WM cells by inhibition of geranylgeranylated proteins. Furthermore, simvastatin overcame tumour cell growth induced by co-culture of WM cells with bone-marrow stromal cells. Simvastatin also decreased IgM secretion by BCWM.1 cells at an early time-point that had not affected cell survival. Simvastatin-induced cytotoxicity was preceded by a decrease in Akt (protein kinase B, PKB) and extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase (MAPK) pathways at 18 h. In addition, simvastatin induced an increase in stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) MAPK followed by caspase-8, -9, -3 and poly(ADP-ribose) polymerase (PARP) cleavages at 18 h, leading to apoptosis. Furthermore, simvastatin enhanced the cytotoxicity induced by bortezomib, fludarabine and dexamethasone. Our studies therefore support our earlier observation of statin-mediated anti-WM activity and provide the framework for future clinical trials testing simvastatin in WM.
British Journal of Haematology 07/2008; 142(5):775-85. · 4.94 Impact Factor
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Aldo M Roccaro,
Xavier Leleu,
Antonio Sacco, Xiaoying Jia,
Molly Melhem,
Anne-Sophie Moreau,
Hai T Ngo,
Judith Runnels,
Abdelkareem Azab,
Feda Azab,
Nicholas Burwick,
Mena Farag,
Steven P Treon,
Michael A Palladino,
Teru Hideshima,
Dharminder Chauhan,
Kenneth C Anderson,
Irene M Ghobrial
[show abstract]
[hide abstract]
ABSTRACT: Waldenström macroglobulinemia (WM) is an incurable low-grade B-cell lymphoma characterized by high protein turnover. We dissected the biologic role of the proteasome in WM using 2 proteasome inhibitors, NPI-0052 and bortezomib. We found that NPI-0052 inhibited proliferation and induced apoptosis in WM cells, and that the combination of NPI-0052 and bortezomib induced synergistic cytotoxicity in WM cells, leading to inhibition of nuclear translocation of p65NF-kappaB and synergistic induction of caspases-3, -8, and -9 and PARP cleavage. These 2 agents inhibited the canonical and noncanonical NF-kappaB pathways and acted synergistically through their differential effect on Akt activity and on chymotrypsin-like, caspaselike, and trypsinlike activities of the proteasome. We demonstrated that NPI-0052-induced cytotoxicity was completely abrogated in an Akt knockdown cell line, indicating that its major activity is mediated through the Akt pathway. Moreover, we demonstrated that NPI-0052 and bortezomib inhibited migration and adhesion in vitro and homing of WM cells in vivo, and overcame resistance induced by mesenchymal cells or by the addition of interleukin-6 in a coculture in vitro system. Theses studies enhance our understanding of the biologic role of the proteasome pathway in WM, and provide the preclinical basis for clinical trials of combinations of proteasome inhibitors in WM.
Blood 06/2008; 111(9):4752-63. · 9.90 Impact Factor
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Xavier Leleu,
Jérôme Eeckhoute, Xiaoying Jia,
Aldo M Roccaro,
Anne-Sophie Moreau,
Mena Farag,
Antonio Sacco,
Hai T Ngo,
Judith Runnels,
Molly R Melhem, [......],
Feda Azab,
Zachary Hunter,
Evdoxia Hatjiharissi,
Daniel R Carrasco,
Steven P Treon,
Thomas E Witzig,
Teru Hideshima,
Myles Brown,
Kenneth C Anderson,
Irene M Ghobrial
[show abstract]
[hide abstract]
ABSTRACT: The nuclear factor-kappaB (NF-kappaB) path-way has been implicated in tumor B-cell survival, growth, and resistance to therapy. Because tumor cells overcome single-agent antitumor activity, we hypothesized that combination of agents that target differentially NF-kappaB pathway will induce significant cytotoxicity. Therapeutic agents that target proteasome and Akt pathways should induce significant activity in B-cell malignancies as both pathways impact NF-kappaB activity. We demonstrated that perifosine and bortezomib both targeted NF-kappaB through its recruitment to the promoter of its target gene IkappaB using chromatin immunoprecipitation assay. This combination led to synergistic cytotoxicity in Waldenstrom macroglobulinemia (WM) cells that was mediated through a combined reduction of the PI3K/Akt and ERK signaling pathways, found to be critical for survival of WM cells. Moreover, a combination of these drugs with the CD20 monoclonal antibody rituximab further increased their cytotoxic activity. Thus, effective WM therapy may require combination regimens targeting the NF-kappaB pathway.
Blood 06/2008; 111(10):5068-77. · 9.90 Impact Factor
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Aldo M Roccaro,
Xavier Leleu,
Antonio Sacco,
Anne-Sophie Moreau,
Evdoxia Hatjiharissi, Xiaoying Jia,
Lian Xu,
Bryan Ciccarelli,
Christopher J Patterson,
Hai T Ngo,
Domenico Russo,
Angelo Vacca,
Franco Dammacco,
Kenneth C Anderson,
Irene M Ghobrial,
Steven P Treon
[show abstract]
[hide abstract]
ABSTRACT: Resveratrol (3,4',5-tri-hydroxy-trans-stilbene) is an antioxidant constituent of a wide variety of plant species including grapes. It has gained considerable attention because of its anticancer properties, as shown in solid and hematologic malignancies. Whether resveratrol could inhibit proliferation or induce cytotoxicity in Waldenström's macroglobulinemia (WM) was investigated.
We studied resveratrol-induced inhibition of proliferation and induction of cytotoxicity in WM cell lines, WM primary tumor cells, IgM-secreting cells, and peripheral blood mononuclear cells. The mechanisms of action and different signaling pathways involved were studied using Western blot and gene expression profile analysis. Resveratrol activity was also evaluated in the bone marrow microenvironment. We finally investigated whether or not resveratrol could have any synergistic effect if used in combination with other drugs widely used in the treatment of WM.
A schematic image illustrating the location and expression of the aurora kinases A, B, and C during mitosis. Resveratrol inhibited proliferation and induced cytotoxicity against WM cells, IgM-secreting cells, as well as primary WM cells, without affecting peripheral blood mononuclear cells; down-regulated Akt, extracellular signal-regulated kinase mitogen-activated protein kinases, and Wnt signaling pathways, as well as Akt activity; induced cell cycle arrest and apoptosis; and triggered c-Jun-NH(2)-terminal-kinase activation, followed by the activation of intrinsic and extrinsic caspase pathways. Lastly, adherence to bone marrow stromal cells did not confer protection to WM cells against resveratrol-induced cytotoxicity. Furthermore, resveratrol showed synergistic cytotoxicity when combined with dexamethasone, fludarabine, and bortezomib.
Our data show that resveratrol has significant antitumor activity in WM, providing the framework for clinical trials in this disease.
Clinical Cancer Research 04/2008; 14(6):1849-58. · 7.74 Impact Factor
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Alissa Huston,
Xavier Leleu, Xiaoying Jia,
Anne-Sophie Moreau,
Hai T Ngo,
Judith Runnels,
Judy Anderson,
Yazan Alsayed,
Aldo Roccaro,
Sonia Vallet,
Evdoxia Hatjiharissi,
Yu-Tsu Tai,
Peter Sportelli,
Nikhil Munshi,
Paul Richardson,
Teru Hideshima,
David G Roodman,
Kenneth C Anderson,
Irene M Ghobrial
[show abstract]
[hide abstract]
ABSTRACT: We hypothesized that targeting both Akt and heat shock protein (HSP) 90 would induce cytotoxic activity against multiple myeloma (MM) cells and target the bone marrow (BM) microenvironment to inhibit angiogenesis, osteoclast formation, as well as migration and adhesion of MM cells.
MM cell lines were incubated with perifosine (5 and 10 micromol/L) and 17-(dimethylaminoethylamino)-17-demethoxygeldanamycin (17-DMAG; 50 and 100 nmol/L) alone and in combination.
The combination of Akt inhibitor perifosine and HSP90 inhibitor 17-DMAG was synergistic in inducing MM cell cytotoxicity, evidenced by inhibition of DNA synthesis and induction of apoptosis. In addition, perifosine and 17-DMAG almost completely inhibited osteoclast formation: perifosine interfered with both early and late stages of osteoclast progenitor development, whereas 17-DMAG targeted only early stages. We next showed that combined therapy overcomes tumor growth and resistance induced by BM stromal cells and endothelial cells as well as the proliferative effect of exogenous interleukin-6, insulin-like growth factor-I, and vascular endothelial growth factor. Moreover, the combination also induced apoptosis and growth inhibition in endothelial cells and inhibited angiogenesis. Finally, we showed that the two agents prevented migration of MM cells toward stromal-derived factor-1 and vascular endothelial growth factor, which are present in the BM milieu, and also prevented adhesion of MM cells to fibronectin.
This study provides the preclinical framework for treatment protocols targeting both the Akt and HSP pathways in MM.
Clinical Cancer Research 03/2008; 14(3):865-74. · 7.74 Impact Factor
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Xavier Leleu, Xiaoying Jia,
Judith Runnels,
Hai T Ngo,
Anne-Sophie Moreau,
Mena Farag,
Joel A Spencer,
Costas M Pitsillides,
Evdoxia Hatjiharissi,
Aldo Roccaro,
Garrett O'Sullivan,
Douglas W McMillin,
Daisy Moreno,
Tanyel Kiziltepe,
Ruben Carrasco,
Steven P Treon,
Teru Hideshima,
Kenneth C Anderson,
Charles P Lin,
Irene M Ghobrial
[show abstract]
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ABSTRACT: Waldenstrom macroglobulinemia (WM) is an incurable low-grade lymphoplasmacytic lymphoma. We demonstrate up-regulated Akt activity in WM, and that Akt down-regulation by Akt knockdown and the inhibitor perifosine leads to significant inhibition of proliferation and induction of apoptosis in WM cells in vitro, but not in normal donor peripheral blood and hematopoietic progenitors. Importantly, down-regulation of Akt induced cytotoxicity of WM cells in the bone marrow microenvironment (BMM) context. Perifosine induced significant reduction in WM tumor growth in vivo in a subcutaneous xenograft model through inhibition of Akt phosphorylation and downstream targets. We also demonstrated that Akt pathway down-regulation inhibited migration and adhesion in vitro and homing of WM tumor cells to the BMM in vivo. Proteomic analysis identified other signaling pathways modulated by perifosine, such as activation of ERK MAPK pathway, which induces survival of tumor cells. Interestingly, MEK inhibitor significantly enhanced perifosine-induced cytotoxicity in WM cells. Using Akt knockdown experiments and specific Akt and PI3K inhibitors, we demonstrated that ERK activation is through a direct effect, rather than feedback activation, of perifosine upstream ERK pathway. These results provide understanding of biological effects of Akt pathway in WM and provide the framework for clinical evaluation of perifosine in WM patients.
Blood 01/2008; 110(13):4417-26. · 9.90 Impact Factor
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Steven P Treon,
Evdoxia Hatjiharissi,
Xavier Leleu,
Anne-Sophie Moreau,
Aldo Roccaro,
Zachary R Hunter,
Jacob D Soumerai,
Bryan Ciccarelli,
Lian Xu,
Antonio Sacco, [......],
Andrew R Branagan,
Allen W Ho,
Daniel D Santos,
Olivier Tournilhac,
Robert J Manning,
Renee Leduc,
Kelly O'Connor,
Marybeth Nelson,
Christopher J Patterson,
Irene Ghobrial
[show abstract]
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ABSTRACT: Waldenström's macroglobulinemia is a B-cell disorder characterized by bone marrow infiltration with lymphoplasmacytic cells and demonstration of an immunoglobulin M monoclonal gammopathy. Despite advances in therapy, Waldenström's macroglobulinemia remains incurable. As such, novel therapeutic agents are needed for the treatment of Waldenström's macroglobulinemia. In ongoing efforts, we and others have sought to exploit advances made in the understanding of the biology of Waldenström's macroglobulinemia so as to better target therapeutics for this malignancy. Importantly, as part of these efforts, we have prioritized the development of stem cell-sparing drugs because autologous stem cell transplantation remains a viable salvage option in Waldenström's macroglobulinemia. These efforts have led to the development of several novel agents for treating Waldenström's macroglobulinemia, including bortezomib; monoclonal antibodies and/or blocking protein targeting CD40, CD52, or CD70, a proliferation-inducing ligand and B-lymphocyte stimulator; the immunomodulator thalidomide as an enhancer of rituximab activity, as well as agents interfering with stem cell factor, phosphatidylinositol 3-kinase/Akt, phosphodiesterase, cholesterol, and protein kinase C beta signaling. This report provides an update on biologic studies and clinical efforts for the development of these novel agents in the treatment of Waldenström's macroglobulinemia.
Clinical Lymphoma & Myeloma 09/2007; 7 Suppl 5:S199-206. · 1.13 Impact Factor
