Hypoxia Activated Prodrug TH-302 for the Treatment of Multiple Myeloma.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 3838-3838
Author(s):  
Jinsong Hu ◽  
Damian R Handisides ◽  
Els Van Valckenborgh ◽  
Hendrik De Raeve ◽  
Eline Menu ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Multiple Myeloma ◽  
Bone Marrow ◽  
Solid Tumors ◽  
Cycle Phase ◽  
Therapeutic Effects ◽  
Dependent Manner ◽  
Myeloma Cells ◽  
Hypoxic Conditions

Abstract Abstract 3838 Poster Board III-774 Hypoxia is known to be linked to increased metastatic potential and a treatment-resistant phenotype leading to rapid progression and poor prognosis in solid tumors. We confirmed previous data[1] on hypoxia in human multiple myeloma (MM) in the 5T33MM syngeneic murine model of MM by using H&E staining and Hypoxyprobe (Pimonidazole) staining on consecutive serial sections from both naive mice and 5T33MMvv diseased mice. We observed a physiological hypoxic situation in MM diseased bone marrow. Given the contribution of hypoxia to tumor progression and drug resistance, a number of hypoxia-targeted therapeutics are under development. TH-302 is a new hypoxia-activated prodrug (HAP) that is currently being evaluated in the clinical trials as monotherapy and in combination with standard chemotherapy regimens for the treatment of solid tumors. The aims of the current study are (1) to demonstrate the effects of TH302 on MM cells in hypoxic conditions, focusing on apoptosis and cell cycle and associated signaling pathways and (2) to evaluate potential therapeutic effects when used in an experimental mouse MM model. We evaluated the effects of TH-302 in vitro on the murine 5T33MMvt cell line and the human LP-1, MMS-1, RPMI-8226, Karpas MM cell lines. Flow cytometry analysis revealed that TH-302 (0.5-50μM) can induce significant Go/G1 cell cycle phase arrest and apoptosis in hypoxic conditions (both 1% and 0% O2) in a concentration dependent manner, in contrast to normoxic conditions (20% O2) (p<0.001). Western blot confirmed that treatment with TH-302 in hypoxic conditions down-regulates cyclin D1/2/3, CDK4/6 and pRb expressions, but CDK2 expression was not disturbed. Furthermore, treatment with TH-302 in hypoxic conditions down-regulates the anti-apoptotic proteins BCL-2 and BCL-xL, as well as up-regulates the expression of three proapoptotic proteins: cleaved caspase-3, 9 and PARP. The expression pattern of Bax was however not influenced. The expression of p21 and p27 decreased in hypoxic condition after treatment with TH-302. Further studies conducted in the 5T33MMvv mouse model demonstrated that animals treated prophylactically with TH-302 (12.5 mg/kg, 25 mg/kg and 50 mg/kg, i.p.) for 3 weeks from day 1 after tumor inoculation showed decreased serum paraprotein (12.5 mg/kg, 32% decrease, p<0.05; 25 mg/kg, 77% decrease, p<0.001; 50 mg/kg, 54% decrease, p<0.001), compared to vehicle-treated 5T33MMvv mice (n=10). The frequency of apoptotic multiple myeloma cells in bone marrow sections was also significantly increased (12.5 mg/kg, 2.5 fold, p<0.05; 25mg/kg, 2.1 fold, p<0.05; 50mg/kg, 3.1 fold, p<0.01). Treatment with TH-302 resulted in no adverse events, any observable detriment to the mice or weight loss (p>0.05). In conclusion, these results show that hypoxia-activated treatment with TH-302 activates apoptosis and induces cell cycle arrest in MM cells, under hypoxic conditions, both in vitro and in vivo and therefore represents a promising therapeutic approach for multiple myeloma. Reference [1] Simona Colla, Paola Storti, Gaetano Donofrio, et al. Hypoxia and Hypoxia Inducible Factor (HIF)-1α in Multiple Myeloma: Effect on the Pro-Angiogenic Signature of Myeloma Cells and the Bone Marrow Microenvironment, 50th ASH annual meeting, http://ash.confex.com/ash/2008/webprogram/Paper13156.html Disclosures: Handisides: Treshold Pharmaceuticals: Employment. Liu:Treshold Pharmaceuticals: Employment. Sun:Treshold Pharmaceuticals: Employment. Hart:Treshold Pharmaceuticals: Employment. Vanderkerken:Treshold Pharmaceuticals: Research Funding.

OSU-HDAC42, a Novel Histone Deacetylase Inhibitor, Induces Apoptosis in a Caspase-Dependent Manner and Induces p21WAF1/CIP1 and p16 Expression in Multiple Myeloma Cell Lines.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 5078-5078
Author(s):  
Valerie L. White ◽  
Shuhong Zhang ◽  
David Lucas ◽  
Ching-Shih Chen ◽  
Sherif S. Farag
Keyword(s):  
Cell Cycle ◽  
Multiple Myeloma ◽  
Histone Deacetylase ◽  
Histone Deacetylase Inhibitor ◽  
Myeloma Cell ◽  
Dependent Manner ◽  
In Vitro Activity ◽  
Myeloma Cells ◽  
Deacetylase Inhibitor

Abstract Multiple myeloma (MM) is a neoplastic disorder characterized by accumulation of slowly-proliferating clonal plasma cells. OSU-HDAC42 [a.k.a. (S)-HDAC-42] is a novel histone deacetylase inhibitor that induces apoptosis in various types of cancer cells and is being developed as an anti-cancer therapy in the NCI Rapid Access to Intervention Therapy (RAID) program. In this study, we tested the in vitro activity of OSU-HDAC42 against human MM cells. OSU-HDAC42 induced myeloma cell death, with an LC50 of less than 1.6μM after 48 hours in the four cell lines tested - U266, IM-9, RPMI 8226 and ARH-77 using the MTT assay. OSU-HDAC42 induced cleavage of caspases 3, 8 and 9, as well as polyADP-ribose polymerase (PARP). Addition of the pan-caspase inhibitor Q-VD-OPH before exposure to the drug prevented apoptosis at 48 hours, as determined by Annexin V/propidium iodide staining. These results indicate that OSU-HDAC42 induced apoptosis by a mainly caspase-dependent manner. Bax expression was up-regulated at 24 and 48 hours, while Bcl-2 remains relatively constant. Mcl-1 showed increasing cleavage at increasing doses of OSU-HDAC42. These findings support a mitochondrial pathway of apoptosis. Cell cycle suppressor proteins p21WAF1/CIP1 and p16 were also significantly induced after treatment with the drug, suggesting that OSU-HDAC42 may also acts on pathways to halt cell cycle progression. In addition, the gp130 (signal-transducing) subunit of the IL-6 receptor was down-regulated by OSU-HDAC42 exposure. The tyrosine-phosphorylated form of STAT3, which is phosphorylated by dimerized gp130, was also dramatically reduced following incubation with OSU-HDAC42, supporting the finding that gp130 expression is diminished. As IL-6 is an important growth and survival factor for MM cells, down-regulation of gp130 may be an important mechanism for the activity of OSU-HDAC42 against MM cells. TRAIL, FasL, XIAP, and p53 expression were not affected by OSU-HDAC42. While other HDAC inhibitors have been shown to activate the death receptor pathway or down-regulate XIAP, this was not observed with OSU-HDAC42 in myeloma cells. In conclusion, OSU-HDAC42 has in vitro activity against myeloma cells and acts via activation of caspases, inducing the cell cycle suppressors p21WAF1/CIP1 and p16, as well as interfering with the IL-6 signal transduction pathway.

Targeting the multiple myeloma hypoxic niche with TH-302, a hypoxia-activated prodrug

Blood ◽  
2010 ◽  
Vol 116 (9) ◽  
pp. 1524-1527 ◽  
Author(s):  
Jinsong Hu ◽  
Damian R. Handisides ◽  
Els Van Valckenborgh ◽  
Hendrik De Raeve ◽  
Eline Menu ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Bone Marrow ◽  
Metastatic Potential ◽  
Treatment Target ◽  
Hypoxic Conditions ◽  
Cycle Arrest ◽  
G1 Cell Cycle Arrest ◽  
New Treatment

Hypoxia is associated with increased metastatic potential and poor prognosis in solid tumors. In this study, we demonstrated in the murine 5T33MM model that multiple myeloma (MM) cells localize in an extensively hypoxic niche compared with the naive bone marrow. Next, we investigated whether hypoxia could be used as a treatment target for MM by evaluating the effects of a new hypoxia-activated prodrug TH-302 in vitro and in vivo. In severely hypoxic conditions, TH-302 induces G0/G1 cell-cycle arrest by down-regulating cyclinD1/2/3, CDK4/6, p21cip-1, p27kip-1, and pRb expression, and triggers apoptosis in MM cells by up-regulating the cleaved proapoptotic caspase-3, -8, and -9 and poly ADP-ribose polymerase while having no significant effects under normoxic conditions. In vivo treatment of 5T33MM mice induces apoptosis of the MM cells within the bone marrow microenvironment and decreases paraprotein secretion. Our data support that hypoxia-activated treatment with TH-302 provides a potential new treatment option for MM.

Angiopoietin-1 and Osteopontin Expression by CD138+ Myeloma Cells Rather Than VEGF and CD45 Correlates with Bone Marrow Angiogenesis in Multiple Myeloma Patients at the Diagnosis.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 2501-2501
Author(s):  
Nicola Giuliani ◽  
Simona Colla ◽  
Francesca Morandi ◽  
Sabrina Bonomini ◽  
Mirca Lazzaretti ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Bone Marrow ◽  
Linear Trend ◽  
The Other ◽  
Vegf Mrna ◽  
Myeloma Cells ◽  
Other Hand ◽  
Significant Difference ◽  
Angiopoietin 1

Abstract Bone marrow (BM) angiogenesis is increased in Multiple Myeloma (MM) patients and correlates with disease progression and patient survival. Myeloma cells secrete the main endothelial growth factor VEGF. In mouse models VEGF secretion as well as the angiogenic properties of MM cells correlate with the lack of CD45 expression by MM cells. However, recent data indicate that VEGF plasma cell expression is similar between MGUS and MM patients suggesting that other molecules could be involved. In line with this hypothesis we have recently demonstrated that myeloma cells may also produce factors with angiogenic properties as angiopoietin-1 (ANG-1) and osteopontin (OPN) that are involved in myeloma induced angiogenesis in vitro. In order to identify which factors correlate with BM angiogenesis in MM patients, we have investigated in a cohort of 121 newly diagnosed MM patients (stage I–III) the expression of the angiogenic molecules VEGF, ANG-1 and OPN and their correlation with bone marrow (BM) angiogenesis and CD45 expression by MM cells. We found that 90% of CD138+ MM cells tested were positive for VEGF mRNA. On the other hand we found that 50% and 40 % of MM patients were positive for ANG-1 and OPN mRNA respectively. Using the previously published cut off for CD45 expression we found that 61 out of 121 MM patients were positive for CD45 and 60 out of 121 were negative for CD45 expression. Any correlation was not observed between VEGF expression and BM angiogenesis in MM patients (p=0.5), whereas the number of microvessels X field was higher in Ang-1 positive patients in comparison with Ang-1 negative ones (mean±SE: 6.23±0.2 vs. 2.94±0.1, median: 6.21 vs. 2.79; p=0.001,) and the microvascular density (MVD) was significantly increased (32.98±1.7 vs. 14.55±1.3, median: 34.69 vs. 13.04; p&lt;0.01; capillaries: 26.73±1.3 vs. 10.42±0.8, median: 24.06 vs. 9.04; p&lt;0.01, small venules: 9.56 ±0.5 vs. 4.14±0.5, median: 10.60 vs. 3.65; p&lt;0.01). Furthermore a significantly positive correlation between Ang-1 expression and MVD was found (Pearson Chi-square: p=0.036, Cochran’s Linear Trend: p=0.01). A significantly higher MVD was also observed in the group of patients positive for OPN, (mean±SE: 29.1±0.7 vs. 17.55±0.37; p&lt;0.01) and similarly, the number of microvessels per field was higher in OPN positive patients in comparison with OPN negative ones (mean±SE: 6.7±0.15 vs. 4.28±0.04; p=0.05). On the other hand, any significant difference was not observed between CD45 positive and CD45 negative patients for the expression of VEGF (p=0.4), ANG-1 (p=0.3) and OPN (p=0.09). Consistently we did not find any significant difference in both MVD and number of vessels X field between CD45 positive patients as compared with CD45 negative ones (p=0.5 and p=0.4, respectively). Finally, a multivariate analysis confirmed that VEGF and CD45 did not correlate with the BM angiogenesis showing that ANG-1 expression by MM cells was more tightly correlated with MVD and the number of vessels X field as compared to OPN. Our data indicate that ANG-1 and in part OPN rather than VEGF and CD45 expression by MM cells are the critical determinants correlated with the increase of BM angiogenesis that occurs in MM patients at the diagnosis.

CS1: A Potential New Therapeutic Target for the Treatment of Multiple Myeloma.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 3457-3457 ◽  
Author(s):  
Eric D. Hsi ◽  
Roxanne Steinle ◽  
Balaji Balasa ◽  
Aparna Draksharapu ◽  
Benny Shum ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Bone Marrow ◽  
Flow Cytometry ◽  
B Cell ◽  
Mononuclear Cells ◽  
Plasma Cells ◽  
Target Cells ◽  
Dependent Manner ◽  
Myeloma Cells ◽  
Effector Cells

Abstract Background: To identify genes upregulated in human memory B and plasma cells, naïve B cell cDNA was subtracted from plasma cell and memory B cell cDNA. One gene that was highly expressed in plasma cells encodes CS1 (CD2 subset 1, CRACC, SLAMF7), a cell surface glycoprotein of the CD2 family. CS1 was originally identified as a natural killer (NK) cell marker. Monoclonal antibodies (mAbs) specific for CS1 were used to validate CS1 as a potential target for the treatment of multiple myeloma (MM). Methods: Anti-CS1 mAbs were generated by immunizing mice with a protein comprising of the extracellular domain of CS1. Two clones, MuLuc63 and MuLuc90, were selected to characterize CS1 protein expression in normal and diseased tissues and blood. Fresh frozen tissue analysis was performed by immunohistochemistry (IHC). Blood and bone marrow analysis was performed using flow cytometry with directly conjugated antibodies. HuLuc63, a novel humanized anti-CS1 mAb (derived from MuLuc63) was used for functional characterization in non-isotopic LDH-based antibody-dependent cellular cytotoxicity (ADCC) assays. Results: IHC analysis showed that anti-CS1 staining occurred only on mononuclear cells within tissues. The majority of the mononuclear cells were identified as tissue plasma cells by co-staining with anti-CD138 antibodies. No anti-CS1 staining was detected on the epithelia, smooth muscle cells or vessels of any normal tissues tested. Strong anti-CS1 staining was also observed on myeloma cells in 9 of 9 plasmacytomas tested. Flow cytometry analysis of whole blood from both normal healthy donors and MM patients showed specific anti-CS1 staining in a subset of leukocytes, consisting primarily of CD3−CD(16+56)+ NK cells, CD3+CD(16+56)+ NKT cells, and CD3+CD8+ T cells. Flow cytometry of MM bone marrow showed a similar leukocyte subset staining pattern, except that strong staining was also observed on the majority of CD138+CD45−/dim to + myeloma cells. No anti-CS1 binding was detected to hematopoietic CD34+CD45+ stem cells. To test if antibodies towards CS1 may have anti-tumor cell activity in vitro, ADCC studies using effector cells (peripheral blood mononuclear cells) from 23 MM patients and L363 MM target cells were performed. The results showed that HuLuc63, a humanized form of MuLuc63, induced significant ADCC in a dose dependent manner. Conclusions: Our study identifies CS1 as an antigen that is uniformly expressed on normal and neoplastic plasma cells at high levels. The novel humanized anti-CS1 mAb, HuLuc63, exhibits significant ADCC using MM patient effector cells. These results demonstrate that HuLuc63 could be a potential new treatment for multiple myeloma. HuLuc63 will be entering a phase I clinical study for multiple myeloma.

NVP-LAQ824 is a potent novel histone deacetylase inhibitor with significant activity against multiple myeloma

Blood ◽  
2003 ◽  
Vol 102 (7) ◽  
pp. 2615-2622 ◽  
Author(s):  
Laurence Catley ◽  
Ellen Weisberg ◽  
Yu-Tzu Tai ◽  
Peter Atadja ◽  
Stacy Remiszewski ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Bone Marrow ◽  
Histone Deacetylase ◽  
Hdac Inhibitors ◽  
Myeloma Cell ◽  
Parp Cleavage ◽  
Significant Activity ◽  
Dependent Manner

Abstract Histone deacetylase (HDAC) inhibitors are emerging as a promising new treatment strategy in hematologic malignancies. Here we show that NVP-LAQ824, a novel hydroxamic acid derivative, induces apoptosis at physiologically achievable concentrations (median inhibitory concentration [IC50] of 100 nM at 24 hours) in multiple myeloma (MM) cell lines resistant to conventional therapies. MM.1S myeloma cell proliferation was also inhibited when cocultured with bone marrow stromal cells, demonstrating ability to overcome the stimulatory effects of the bone marrow microenvironment. Importantly, NVP-LAQ824 also inhibited patient MM cell growth in a dose- and time-dependent manner. NVP-LAQ824-induced apoptotic signaling includes up-regulation of p21, caspase cascade activation, and poly (adenosine diphosphate [ADP]) ribose (PARP) cleavage. Apoptosis was confirmed with cell cycle analysis and annexin-propidium iodide staining. Interestingly, treatment of MM cells with NVPLAQ824 also led to proteasome inhibition, as determined by reduced proteasome chymotrypsin-like activity and increased levels of cellular polyubiquitin conjugates. Finally, a study using NVP-LAQ824 in a preclinical murine myeloma model provides in vivo relevance to our in vitro studies. Taken together, these findings provide the framework for NVP-LAQ824 as a novel therapeutic in MM. (Blood. 2003;102:2615-2622)

Mcl-1 Is Overexpressed in Multiple Myeloma and Correlates with Disease Severity.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 1419-1419
Author(s):  
Soraya Wuilleme-Toumi ◽  
Nelly Robillard ◽  
Patricia Gomez-Bougie ◽  
Philippe Moreau ◽  
Steven Le Gouill ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Bone Marrow ◽  
Disease Severity ◽  
Cell Lines ◽  
Plasma Cells ◽  
Myeloma Cell ◽  
Lymphocytic Leukemia ◽  
Myeloma Cells

Abstract Multiple Myeloma (MM) is a fatal malignancy of B-cell origin characterized by the accumulation of plasma cells within the bone marrow. The expression of the pro-survival members of the Bcl-2 family has been shown to be a key process in the survival of myeloma cells. More particularly, Mcl-1 expression turned out to be critical for their survival. Indeed, knockdown of Mcl-1 by antisenses induces apoptosis in myeloma cells. Finally, Mcl-1 was found to be the only anti-apoptotic Bcl-2 family member which level of expression was modified by cytokine treatment of myeloma cells. For these reasons, we have evaluated the expression of Mcl-1 in vivo in normal, reactive and malignant plasma cells (PC) i.e., myeloma cells from 55 patients with MM and 20 human myeloma cell lines using flow cytometry. We show that Mcl-1 is overexpressed in MM in comparison with normal bone marrow PC. Forty-seven percent of patients with MM at diagnosis (p=.017) and 80% at relapse (p=.014 for comparison with diagnosis) overexpress Mcl-1. Of note, only myeloma cell lines but not reactive plasmocytoses have abnormal Mcl-1 expression, although both plasmocyte expansion entities share similar high proliferation rates (&gt;20%). Of interest, Bcl-2 as opposed to Mcl-1, does not discriminate malignant from normal PC. This shows that the overexpression of Mcl-1 is clearly related to malignancy rather than to proliferation. It will be important to know whether the overexpression of Mcl-1 is related to an abnormal response to cytokines like Interleukin-6 or to mutations of the promoter of the Mcl-1 gene as already described in B chronic lymphocytic leukemia. Finally, level of Mcl-1 expression is related to disease severity, the highest values being correlated with the shortest event-free survival (p=.01). In conclusion, Mcl-1 which has been shown to be essential for the survival of human myeloma cells in vitro is overexpressed in vivo in MM and correlates with disease severity. Mcl-1 represents a major therapeutical target in MM.

Valproic Acid Inihibts Histone Deacetylases and Proliferation and Induces Cell Cycle Arrest and Apoptosis in Multiple Myeloma.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 5165-5165
Author(s):  
Martin Kaiser ◽  
Ulrike Heider ◽  
Ivana Zavrski ◽  
Jan Sterz ◽  
Kurt Possinger ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Multiple Myeloma ◽  
Valproic Acid ◽  
Cell Lines ◽  
Myeloma Cell ◽  
G1 Phase ◽  
Dependent Manner ◽  
Myeloma Cells ◽  
Cycle Arrest ◽  
Dose Dependent

Abstract Multiple myeloma remains an incurable disease in the majority of the patients and novel treatment strategies are urgently needed. A new class of drugs, the histone deacetylase (HDAC) inhibitors take influence in epigenetic modifications and have antiproliferative effects in some malignancies. Valproic acid (VPA) is an anticonvulsant drug and was recently shown to inhibit HDACs and suppress tumor growth. The drug is currently being evaluated in clinical studies in acute myeloid leukemia. Its effects on myeloma cells are unknown. The aim of this study was to evaluate the effects of VPA on proliferation, apoptosis and HDAC inhibition in multiple myeloma cell lines as well as in sorted human bone marrow multiple myeloma cells. Myeloma cell lines, OPM-2, NCI-H929, LP-1, and freshly isolated multiple myeloma cells from bone marrow aspirates were exposed to different concentrations of VPA for 4 to 72 hours. Cell proliferation, cell cycle distribution and apoptosis were assayed in reaction to the treatment. Proliferation decreased noticeably and apoptosis was induced in a dose-dependent manner in multiple myeloma cell lines as well as in freshly sorted primary myeloma cells. After 48 hours of incubation with VPA at 1 mM, approximately 46%, 52% and 25% of OPM-2, NCI-H929 and LP-1 cell lines had undergone specific apoptosis, respectively. Freshly sorted primary bone marrow myeloma cells from patients showed also specific apoptosis. In cell cycle analysis by flow cytometry, the population of cells in the G0/G1 phase increased, whereas cells in the S phase decreased in a time and dose dependent manner. Incubation of the cell line OPM-2, for example, with 1 mM VPA for 48 hours decreased the proportion of cells in the S phase from 39 % to 6 % of the total cell count and increased cells in the G0/G1 phase from 49 % to 85 %. Acetylation of histones and expression of cyclin D1 and the cell cycle regulators p21 and p27 were studied by western blot. Histone acetylation and p21 concentrations increased after VPA treatment whereas levels of p27 remained constant. A decrease in cyclin D1 concentrations was observed. Subapoptotic doses of VPA significantly decreased the production of VEGF in OPM-2 cell line. These data show that treatment with valproic acid effectively inhibits histone deacetylase activity, leading to the accumulation of acetylated histones in multiple myeloma cells. Parallel upregulation of cell cycle inhibitors like p21WAF1 was observed, together with a reduction of cyclin D1 levels. Myeloma cell proliferation was inhibited in a time and dose dependent manner and cell cycle arrest in the G0/G1 phase was induced by VPA treatment. VPA potently induced apoptosis in all human myeloma cell lines as well as in sorted primary multiple myeloma cells in a dose and time dependent manner. These results show for the first time that VPA acts as an HDAC inhibitor in multiple myeloma cells, induces G1 cell cycle arrest, potently inhibits tumor growth and markedly induces apoptosis. In addition to its direct antitumor effect, valproic acid may exert an antiangiogenic effect by reducing VEGF production in myeloma cells. These data provide the framework for clinical studies with valproic acid in multiple myeloma.

NSC 338258 Represents a Novel Anti-Neoplastic Agent for the Treatment of Multiple Myeloma.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 3469-3469
Author(s):  
Erming Tian ◽  
Terry Landowski ◽  
Owen Stephens ◽  
Shmuel Yaccoby ◽  
Bart Barlogie ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Multiple Myeloma ◽  
Stromal Cells ◽  
Mononuclear Cells ◽  
Myeloma Cell ◽  
Current Data ◽  
Apoptotic Pathway ◽  
Synthetic Compound ◽  
Myeloma Cells

Abstract We have shown that high-risk multiple myeloma (MM) can be linked to amplification and overexpression of the cell cycle regulator CKS1B. With this in mind we correlated high expression of this gene in the NCI60 cell line panel with IC50 of over 10,000 anticancer compounds. NSC 338258 (EPED3) was identified in this search. EPED3 is a highly stable, hydrophilic derivative of ellipticine. In vitro, this synthetic compound exhibits drastic cytotoxic activity on myeloma cells, which is unique among most ellipticine derivatives. This efficacy of EPED3 was examined in myeloma cells co-cultured with bone marrow stromal cells. Despite the protective influence of stromal cells, micromolar concentrations of EPED3 were highly effective at killing myeloma cells; however, this lethal activity was exclusive of stromal cells. In co-culture, EPED3-induced cell cycle arrest and massive apoptotic progression appears to be a consequence of its instant impact on cytoplasmic organelles, particularly mitochondria. Disruption of mitochondrial and endoplasmic distribution of cytochrome c initiated the intracellular proteolytic cascade through the intrinsic apoptotic pathway. Effects of EPED3 treatment were further evaluated in myeloma cell lines with selective tolerances to doxorubicin, dexamethasone, and Velcade; EPED3 overcame these acquired drug resistances. In addition, the potency of EPED3 was tested on mononuclear cells isolated from peripheral blood of healthy donors. Under mitogenic stimulation, EPED3 had no significant growth inhibition effects within a range of concentrations killing myeloma cells. Collectively, our current data suggest that EPED3 is an extraordinary agent that, in vitro, targets mitochondrial function to rapidly deplete chemical energy and to initiate apoptosis in myeloma cells at low concentration, while leaving healthy stromal and mononuclear cells unharmed.

Upregulation of MMP-2 & 9 by Co-Culture of Human Myeloma Cell Lines and Endothelial Cells May Be Responsible for Protection Against Cytotoxic Drugs.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 5080-5080
Author(s):  
Shankaranarayana Paneesha ◽  
Raghu Adya ◽  
Hemali Khanji ◽  
Ed Leung ◽  
C. Vijayasekar ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Bone Marrow ◽  
Endothelial Cells ◽  
Mrna Expression ◽  
Cell Lines ◽  
Myeloma Cell ◽  
Myeloma Cells ◽  
Human Myeloma Cell

Abstract Multiple myeloma is a clonal lymphoproliferative disorder characterised by the proliferation of plasma cells in the bone marrow. Inspite of good initial response, it is associated with universal relapse. We hypothesise this is due to sanctuary provided to myeloma cells by the endothelium. Matrix metalloproteinases (MMPs) are shown play a role in cell growth, invasion, angiogenesis, metastasis and bone degradation. We show here the protection offered by endothelial cells to human myeloma cell lines in in-vitro co-culture with upregulation of MMP-2 & 9 and the role of GM6001 MMP inhibitor (Ilomastat) in overcoming this protection. Human myeloma cell lines (H929, RPMI 8226, U266 & JJN3) with or without endothelial cells (human umbilical vein endothelial cells and EaHy 926 cell line) in-vitro co-culture were treated with melphalan, dexamethasone, arsenic trioxide and Ilomastat. Cytotoxicity/proliferation were assessed by the alamarBlue™ assay (Serotec) and validated by Annexin V-FITC apoptosis detection Kit (Calbiochem) and BrDU proliferation assay (BD Pharmingen™). Gelatin Zymography was used to demonstrate activity of MMP-2 & 9 in the supernatant. MMP-2 and 9 mRNA expression was quantified by Real Time Quantitative PCR (ROCHE). Co-culture of human myeloma cell lines with endothelial cells lead to increase in the proliferation of myeloma cell lines and also protected them from the cytotoxicity of chemotherapeutic agents. MMP-2 & 9 activity was upregulated by the co-culture. MMP-2 mRNA expression in human myeloma cell lines increased following 4 hr co-culture. Treatments with Ilomastat lead to the suppression of proliferation in co-culture in a dose dependent manner, associated with a reduction of MMP-2 and 9 activity. Our study shows endothelial cells offer protection to human myeloma cell lines in the presence of cytotoxic agents. This may result in the sanctuary of myeloma cells in bone marrow leading to ultimate relapse of disease. Our study also demonstrates the upregulation of MMP-2 and 9 by co-culture and increased cytotoxicity achieved by the inhibition of MMPs. Further studies are needed to determine the exact role of MMPs in myeloma biology as MMP inhibition may be an interesting therapeutic target and help in averting relapse in multiple myeloma.

The Tyrophostin Adaphostin (NSC680410) Inhibits Multiple Myeloma Bone Marrow Angiogenesis In Vitro and In Vivo.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 2507-2507 ◽  
Author(s):  
Klaus Podar ◽  
Jing Zhang ◽  
Marc S. Raab ◽  
Sonia Vallet ◽  
Mariateresa Fulciniti ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Bone Marrow ◽  
Endothelial Cells ◽  
Endothelial Cell ◽  
Dependent Manner ◽  
Antiangiogenic Effect ◽  
Myelocytic Leukemia ◽  
Endothelial Cell Growth

Abstract Our own and other previous studies demonstrate marked anti-proliferative activity of the tyrophostin adaphostin (NSC680410) in a variety of hematologic malignancies including chronic myelocytic leukemia (CML), chronic lymphcytic leukemia (CLL), acute myelocytic leukemia (AML), and Multiple Myeloma. Here we show that adaphostin (NSC680410), similar to bortezomib, additionally inhibits tumor angiogenesis within the MM bone marrow (BM) microenvironment. This effect is elicited both indirectly by inhibition of VEGF production and secretion in MM cells, as well as directly by abrogation of endothelial cell growth. Specifically, adaphostin triggers marked downregulation of nuclear c-Myc expression in MM cells. Both adaphostin, as well as specific downregulation of c-Myc using siRNA, lead to a decrease in cobalt chloride- induced Hif-1alpha- expression and Hif-1alpha activity, as evidenced by western blot analysis and expression of Hif-1alpha- driven luciferase, respectively. Indeed secretion of the Hif-1alpha target gene VEGF is markedly inhibited in a dose- and time- dependent manner. Importantly, neither knockdown of c-Abl expression nor exogenous overexpression of caspase- cleavage- induced c-Abl fragment abrogates drug- induced Hif-1alpha downregulation or inhibition of its activity. Taken together, these results indicate the existence of a c-Myc/ Hif-1alpha- dependent, but c-Abl- independent, pathway modulating MM cell production and secretion of VEGF. In contrast, we demonstrate a direct antiangiogenic effect of adaphostin on endothelial cells, similar to H2O2, is mediated via c-Jun upregulation, inhibition of cell proliferation, and the induction of cell apoptosis. Moreover, our data further demonstrate activity of adaphostin within the BM microenvironment. Adaphostin, similar to bortezomib, significantly inhibits VEGF secretion triggered by adhesion of MM cells to BMSCs and endothelial cells. Consequently, conditioned medium derived from adaphostin- treated co-cultures markedly inhibits endothelial cell growth and tubule formation in a dose- dependent manner. Finally, we confirmed these in vitro results using an in vivo xenograft mouse model of human MM. Specifically, western blot analysis, as well as immunohistochemistry, demonstrate marked downregulation of both Hif-1alpha and CD31 in tumors isolated from adaphostin- treated animals versus control animals, confirming the in vivo antiangiogenic effect of adaphostin. Similar effects were obtained using a SCIDhu mouse model as well as a significant decrease of MM- related bone disease, due to anti- VEGF activity of adaphostin. Taken together, these data provide the rationale for the clinical evaluation of adaphostin to target both MM cells and the BM milieu to improve patient outcome in Multiple Myeloma.

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