Publications (14)94.99 Total impact
-
Article: Macrophages and mesenchymal stromal cells support survival and proliferation of multiple myeloma cells.
[show abstract] [hide abstract]
ABSTRACT: Multiple myeloma (MM) is characterized by almost exclusive tropism of malignant cells for the bone marrow (BM) milieu. The survival and proliferation of malignant plasma cells have been shown to rely on interactions with nonmalignant stromal cells, in particular mesenchymal stromal cells (MSCs), in the BM microenvironment. However, the BM microenvironment is composed of a diverse array of cell types. This study examined the role of macrophages, an abundant component of BM stroma, as a potential niche component that supports malignant plasma cells. We investigated the proliferation of MM tumour cell lines when cultured alone or together with MSCs, macrophages, or a combination of MSCs and macrophages, using the carboxyfluorescein succinimidyl ester assay. Consistently, we observed increased proliferation of MM cell lines in the presence of either MSCs or macrophages compared to cell line-only control. Furthermore, the combined co-culture of MSCs plus macrophages induced the greatest degree of proliferation of myeloma cells. In addition to increased proliferation, MSCs and macrophages decreased the rate of apoptosis of myeloma cells. Our in vitro studies provide evidence that highlights the role of macrophages as a key component of the BM microenvironment facilitating the growth of malignant plasma cells in MM.British Journal of Haematology 05/2012; 158(3):336-46. · 4.94 Impact Factor -
Article: Microscale functional cytomics for studying hematologic cancers.
[show abstract] [hide abstract]
ABSTRACT: An important problem in translational cancer research is our limited ability to functionally characterize behaviors of primary patient cancer cells and associated stromal cell types, and relate mechanistic understanding to therapy selection. Functional analyses of primary samples face at least 3 major challenges: limited availability of primary samples for testing, paucity of functional information extracted from samples, and lack of functional methods accessible to many researchers. We developed a microscale cell culture platform that overcomes these limitations, especially for hematologic cancers. A key feature of the platform is the ability to compartmentalize small populations of adherent and nonadherent cells in controlled microenvironments that can better reflect physiological conditions and enable cell-cell interaction studies. Custom image analysis was developed to measure cell viability and protein subcellular localizations in single cells to provide insights into heterogeneity of cellular responses. We validated our platform by assessing viability and nuclear translocations of NF-κB and STAT3 in multiple myeloma cells exposed to different conditions, including cocultured bone marrow stromal cells. We further assessed its utility by analyzing NF-κB activation in a primary chronic lymphocytic leukemia patient sample. Our platform can be applied to myriad biological questions, enabling high-content functional cytomics of primary hematologic malignancies.Blood 03/2012; 119(10):e76-85. · 9.90 Impact Factor -
Article: Impact of high-risk classification by FISH: an eastern cooperative oncology group (ECOG) study E4A03.
[show abstract] [hide abstract]
ABSTRACT: Lenalidomide with dexamethasone is a standard induction treatment regimen for newly diagnosed myeloma (although a Federal Drug Administration indication is still absent). In the context of the Phase 3 clinical trial E4A03 (lenalidomide plus dexamethasone in low or high doses), we queried whether a fluorescence in situ hybridization (FISH)-based genetic classification into high risk (HR) and standard risk (SR) multiple myeloma (MM) would remain clinically significant. Of 445 E4A03 patients, 126 had FISH analysis; 21 were classified HR with t(4;14), t(14;16), or 17p13 deletions. Median survival follow-up approached 3 years. Patients with FISH data tended to be younger and healthier compared to the rest of the study population and, consequently, had superior overall survival (OS) results. Within the FISH cohort, shorter OS in the HR versus SR group (P = 0·004) corresponded to a hazard ratio of 3·48 [95% confidence interval: (1·42-8·53)], an effect also observed in multivariate analysis. Two-year OS rates were 91% for SR MM and 76% for HR MM. There was also evidence of interaction between risk status and treatment (P = 0·026). HR patients were less likely to attain good partial response (SR 46% and HR 30%, Odds Ratio = 2·0 [0·7-5·6]), but overall response rates were not different. FISH-based risk classification retained prognostic significance in patients receiving lenalidomide-based induction.British Journal of Haematology 09/2011; 155(3):340-8. · 4.94 Impact Factor -
Article: Impact of gene expression profiling-based risk stratification in patients with myeloma receiving initial therapy with lenalidomide and dexamethasone.
[show abstract] [hide abstract]
ABSTRACT: Detection of specific chromosomal abnormalities by FISH and metaphase cytogenetics allows risk stratification in multiple myeloma; however, gene expression profiling (GEP) based signatures may enable more specific risk categorization. We examined the utility of 2 GEP-based risk stratification systems among patients undergoing initial therapy with lenalidomide in the context of a phase 3 trial. Among 45 patients studied at baseline, 7 (16%) and 10 (22%), respectively, were high-risk using the GEP70 and GEP15 signatures. The median overall survival for the GEP70 high-risk group was 19 months versus not reached for the rest (hazard ratio = 14.1). Although the medians were not reached, the GEP15 also predicted a poor outcome among the high-risk patients. The C-statistic for the GEP70, GEP15, and FISH based risk stratification systems was 0.74, 0.7, and 0.7, respectively. Here we demonstrate the prognostic value for GEP risk stratification in a group of patients primarily treated with novel agents. This trial was registered at www.clinicaltrials.gov as #NCT00098475.Blood 08/2011; 118(16):4359-62. · 9.90 Impact Factor -
Article: VcR-CVAD induction chemotherapy followed by maintenance rituximab in mantle cell lymphoma: a Wisconsin Oncology Network study.
[show abstract] [hide abstract]
ABSTRACT: Intensive chemotherapy regimens are not feasible in many adults with mantle cell lymphoma (MCL). We sought to build upon our previous experience with a non-intensive regimen, modified R-hyperCVAD chemotherapy (rituximab, cyclophosphamide, vincristine, doxorubicin, dexamethasone) with maintenance rituximab (MR), by the incorporation of bortezomib (VcR-CVAD) and the extension of MR beyond 2 years. Patients with previously untreated MCL received VcR-CVAD chemotherapy every 21 d for six cycles. Patients achieving at least a partial response to induction chemotherapy received rituximab consolidation (375 mg/m(2) × 4 weekly doses) and MR (375 mg/m(2) every 12 weeks × 20 doses). The primary end points were overall and complete response (CR), and secondary endpoints were progression-free (PFS) and overall survival (OS). Thirty patients were enrolled, with a median age of 61 years. All patients had advanced stage disease, and 60% had medium/high MCL International Prognostic Index risk factors. A CR or unconfirmed CR was achieved in 77% of patients. After a median follow-up of 42 months, the 3-year PFS and OS were 63% and 86%, respectively. The observed 3-year PFS and OS with VcR-CVAD in MCL were comparable to reported outcomes with more intensive regimens. A cooperative group trial (E1405) is attempting to replicate these promising results.British Journal of Haematology 08/2011; 155(2):190-7. · 4.94 Impact Factor -
Article: Trends in allogeneic stem cell transplantation for multiple myeloma: a CIBMTR analysis.
[show abstract] [hide abstract]
ABSTRACT: Allogeneic hematopoietic cell transplantation in multiple myeloma is limited by prior reports of high treatment-related mortality. We analyzed outcomes after allogeneic hematopoietic cell transplantation for multiple myeloma in 1207 recipients in 3 cohorts based on the year of transplantation: 1989-1994 (n = 343), 1995-2000 (n = 376), and 2001-2005 (n = 488). The most recent cohort was significantly older (53% > 50 years) and had more recipients after prior autotransplantation. Use of unrelated donors, reduced-intensity conditioning and the blood cell grafts increased over time. Rates of acute graft-versus-host (GVHD) were similar, but chronic GVHD rates were highest in the most recent cohort. Overall survival (OS) at 1-year increased over time, reflecting a decrease in treatment-related mortality, but 5-year relapse rates increased from 39% (95% confidence interval [CI], 33%-44%) in 1989-1994 to 58% (95% CI, 51%-64%; P < .001) in the 2001-2005 cohort. Projected 5-year progression-free survival and OS are 14% (95% CI, 9%-20%) and 29% (95% CI, 23%-35%), respectively, in the latest cohort. Increasing age, longer interval from diagnosis to transplantation, and unrelated donor grafts adversely affected OS in multivariate analysis. Survival at 5 years for subjects with none, 1, 2, or 3 of these risk factors were 41% (range, 36%-47%), 32% (range, 27%-37%), 25% (range, 19%-31%), and 3% (range, 0%-11%), respectively (P < .0001).Blood 06/2011; 118(7):1979-88. · 9.90 Impact Factor -
Article: Bone marrow stromal cells from multiple myeloma patients uniquely induce bortezomib resistant NF-kappaB activity in myeloma cells.
[show abstract] [hide abstract]
ABSTRACT: Components of the microenvironment such as bone marrow stromal cells (BMSCs) are well known to support multiple myeloma (MM) disease progression and resistance to chemotherapy including the proteasome inhibitor bortezomib. However, functional distinctions between BMSCs in MM patients and those in disease-free marrow are not completely understood. We and other investigators have recently reported that NF-kappaB activity in primary MM cells is largely resistant to the proteasome inhibitor bortezomib, and that further enhancement of NF-kappaB by BMSCs is similarly resistant to bortezomib and may mediate resistance to this therapy. The mediating factor(s) of this bortezomib-resistant NF-kappaB activity is induced by BMSCs is not currently understood. Here we report that BMSCs specifically derived from MM patients are capable of further activating bortezomib-resistant NF-kappaB activity in MM cells. This induced activity is mediated by soluble proteinaceous factors secreted by MM BMSCs. Among the multiple factors evaluated, interleukin-8 was secreted by BMSCs from MM patients at significantly higher levels compared to those from non-MM sources, and we found that IL-8 contributes to BMSC-induced NF-kappaB activity. BMSCs from MM patients uniquely enhance constitutive NF-kappaB activity in MM cells via a proteinaceous secreted factor in part in conjunction with IL-8. Since NF-kappaB is known to potentiate MM cell survival and confer resistance to drugs including bortezomib, further identification of the NF-kappaB activating factors produced specifically by MM-derived BMSCs may provide a novel biomarker and/or drug target for the treatment of this commonly fatal disease.Molecular Cancer 01/2010; 9:176. · 3.99 Impact Factor -
Article: Lenalidomide plus high-dose dexamethasone versus lenalidomide plus low-dose dexamethasone as initial therapy for newly diagnosed multiple myeloma: an open-label randomised controlled trial.
[show abstract] [hide abstract]
ABSTRACT: High-dose dexamethasone is a mainstay of therapy for multiple myeloma. We studied whether low-dose dexamethasone in combination with lenalidomide is non-inferior to and has lower toxicity than high-dose dexamethasone plus lenalidomide. Patients with untreated symptomatic myeloma were randomly assigned in this open-label non-inferiority trial to lenalidomide 25 mg on days 1-21 plus dexamethasone 40 mg on days 1-4, 9-12, and 17-20 of a 28-day cycle (high dose), or lenalidomide given on the same schedule with dexamethasone 40 mg on days 1, 8, 15, and 22 of a 28-day cycle (low dose). After four cycles, patients could discontinue therapy to pursue stem-cell transplantation or continue treatment until disease progression. The primary endpoint was response rate after four cycles assessed with European Group for Blood and Bone Marrow Transplant criteria. The non-inferiority margin was an absolute difference of 15% in response rate. Analysis was by modified intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00098475. 445 patients were randomly assigned: 223 to high-dose and 222 to low-dose regimens. 169 (79%) of 214 patients receiving high-dose therapy and 142 (68%) of 205 patients on low-dose therapy had complete or partial response within four cycles (odds ratio 1.75, 80% CI 1.30-2.32; p=0.008). However, at the second interim analysis at 1 year, overall survival was 96% (95% CI 94-99) in the low-dose dexamethasone group compared with 87% (82-92) in the high-dose group (p=0.0002). As a result, the trial was stopped and patients on high-dose therapy were crossed over to low-dose therapy. 117 patients (52%) on the high-dose regimen had grade three or worse toxic effects in the first 4 months, compared with 76 (35%) of the 220 on the low-dose regimen for whom toxicity data were available (p=0.0001), 12 of 222 on high dose and one of 220 on low-dose dexamethasone died in the first 4 months (p=0.003). The three most common grade three or higher toxicities were deep-vein thrombosis, 57 (26%) of 223 versus 27 (12%) of 220 (p=0.0003); infections including pneumonia, 35 (16%) of 223 versus 20 (9%) of 220 (p=0.04), and fatigue 33 (15%) of 223 versus 20 (9%) of 220 (p=0.08), respectively. Lenalidomide plus low-dose dexamethasone is associated with better short-term overall survival and with lower toxicity than lenalidomide plus high-dose dexamethasone in patients with newly diagnosed myeloma. National Cancer Institute, Rockville, MD, USA.The lancet oncology 10/2009; 11(1):29-37. · 14.47 Impact Factor -
Article: Bortezomib-resistant nuclear factor-kappaB activity in multiple myeloma cells.
[show abstract] [hide abstract]
ABSTRACT: Bortezomib (Velcade/PS341), a proteasome inhibitor used in the treatment of multiple myeloma (MM), can inhibit activation of nuclear factor-kappaB (NF-kappaB), a family of transcription factors often deregulated and constitutively activated in primary MM cells. NF-kappaB can be activated via several distinct mechanisms, including the proteasome inhibitor-resistant (PIR) pathway. It remains unknown what fraction of primary MM cells harbor constitutive NF-kappaB activity maintained by proteasome-dependent mechanisms. Here, we report an unexpected finding that constitutive NF-kappaB activity in 10 of 14 primary MM samples analyzed is refractory to inhibition by bortezomib. Moreover, when MM cells were cocultured with MM patient-derived bone marrow stromal cells (BMSC), microenvironment components critical for MM growth and survival, further increases in NF-kappaB activity were observed that were also refractory to bortezomib. Similarly, MM-BMSCs caused PIR NF-kappaB activation in the RPMI8226 MM cell line, leading to increased NF-kappaB-dependent transcription and resistance to bortezomib-induced apoptosis. Our findings show that primary MM cells frequently harbor PIR NF-kappaB activity that is further enhanced by the presence of patient-derived BMSCs. They also suggest that this activity is likely relevant to the drug resistance development in some patients. Further elucidation of the mechanism of PIR NF-kappaB regulation could lead to the identification of novel diagnostic biomarkers and/or therapeutic targets for MM treatment.Molecular Cancer Research 09/2008; 6(8):1356-64. · 4.29 Impact Factor -
Article: Thalidomide maintenance following high-dose melphalan with autologous stem cell support in myeloma.
[show abstract] [hide abstract]
ABSTRACT: Recent experience with thalidomide maintenance after high-dose chemotherapy with autologous stem cell support has demonstrated improvement in progression-free survival (PFS) and overall survival (OS). We further explored the tolerability and efficacy of lower doses of maintenance thalidomide in this single-institution study. Thirty-eight patients with myeloma were enrolled and treated with melphalan 200 mg/m(2) followed by autologous stem cell transplantation. Thalidomide 50 mg per day was started on day > or = 60 after recovery of blood counts and was escalated to a maximum dose of 200 mg per day. Responses were assessed at 2 months, 1 year, and 2 years after transplantation. Of the 38 enrolled patients, 7 patients never received thalidomide. Among 31 patients receiving thalidomide, complete or very good partial responses were observed in 65% and 42% of patients at 1 and 2 years, respectively. Tolerability was a major issue, with only 17 patients completing 1 year of thalidomide. The goal of dosing 200 mg per day was achieved in just 17 of 31 patients, and the median tolerated thalidomide dose was 100 mg per day. Sensory neuropathy was the primary reason for dose modification and discontinuation. No thromboembolic events were observed. The median PFS was 20.8 months, and the median OS was > 60 months. Thalidomide maintenance at a goal dose of 200 mg per day was not feasible in this population, with our data suggesting that 100 mg per day is a more reasonable maintenance dose.Clinical Lymphoma & Myeloma 06/2008; 8(3):153-8. · 1.13 Impact Factor -
Article: MIP-1alpha utilizes both CCR1 and CCR5 to induce osteoclast formation and increase adhesion of myeloma cells to marrow stromal cells.
[show abstract] [hide abstract]
ABSTRACT: Macrophage inflammatory protein-1alpha (MIP-1alpha), an osteoclast (OCL) stimulatory factor produced by primary multiple myeloma (MM) cells, increases bone destruction and tumor burden in murine models of MM. Several chemokine receptors (CCR1, CCR5, and CCR9) mediate the effects of MIP-1alpha. In this study, we determined which of these mediates the effects of MIP-1alpha on human OCL formation and myeloma cells. We employed RT-PCR analysis, neutralizing antibodies to CCR1 and CCR5 as well as a CCR1-specific antagonist and OCL formation assays to identify the MIP-1alpha receptors involved in MIP-1alpha's effects on myeloma cells and OCL formation. RT-PCR analysis demonstrated that both CCR1 and CCR5 were expressed by highly purified human OCL precursors, myeloma cell lines, and purified marrow plasma cells from MM patients. Neutralizing antibodies to CCR1 or CCR5 inhibited MIP-1alpha-induced OCL formation. Furthermore, monocyte chemotactic protein-3 (MCP-3), which binds CCR1 but not CCR5 and the CCR1-specific antagonist, BX471, markedly inhibited OCL formation stimulated with MIP-1alpha. Anti-CCR1, anti-CCR5, or BX471 also inhibited the upregulation of beta1 integrin mRNA in myeloma cells induced by MIP-1alpha, as well as the adherence of myeloma cells to stromal cells and IL-6 production by stromal cells in response to myeloma cells. These data demonstrate that MIP-1alpha utilizes either CCR1 or CCR5 for its effects on OCL formation and myeloma cells, and that blocking either CCR1 or CCR5 inhibits OCL formation and myeloma cell adhesion to stromal cells.Experimental Hematology 04/2005; 33(3):272-8. · 2.90 Impact Factor -
Article: Randomized Phase II trial of two high-dose chemotherapy regimens with stem cell transplantation for the treatment of advanced ovarian cancer in first remission or chemosensitive relapse: a Southwest Oncology Group study.
[show abstract] [hide abstract]
ABSTRACT: To evaluate response rates, progression-free survival (PFS), overall survival (OS), and toxicity of two high-dose chemotherapy regimens with stem cell rescue used to treat patients with recurrent or persistent stage III/IV ovarian cancer, with the goal of taking one forward into a Phase III comparison with conventional therapy. Patients under 65 with clinically or pathologically persistent disease after initial chemotherapy or those relapsing >6 months after a complete remission (CR) were randomized to CMC carboplatin (1500 mg/m(2)), mitoxantrone (75 mg/m(2)), and cyclophosphamide (120 mg/kg)], or CTC: [cisplatin (165 mg/m(2)), thiotepa (600 mg/m(2)), and cyclophosphamide (5625 mg/m(2))] with stem cell rescue. Of 67 randomized, the 32 and 26 eligible in the CMC and CTC arms were matched including age (median 49), maximum tumor diameter, and disease status at transplant. Low-risk disease (maximum diameter disease <or= 0.5 cm and platinum sensitivity) was demonstrated in only approximately one-half of the patients. There were two treatment-related deaths in each arm. The median PFS was 13 and 8 months, respectively, for the CMC and CTC arms. The median OS was 29 and 22 months for the CMC and CTC arms. In a multivariate analysis of PFS, normal CA125 at transplant and CR to primary therapy were significant; for OS, normal CA125 and platinum sensitivity were significant. The CMC regimen was the superior regimen. However, few patients were long-term progression-free survivors. A clinical CR to primary therapy and a normal CA125, seen in a minority of patients, were requirements for a favorable outcome.Gynecologic Oncology 08/2004; 94(1):98-106. · 3.89 Impact Factor -
Article: IL-3 expression by myeloma cells increases both osteoclast formation and growth of myeloma cells.
[show abstract] [hide abstract]
ABSTRACT: Macrophage inflammatory protein-1 alpha (MIP-1 alpha) gene expression is abnormally regulated in multiple myeloma (MM) owing to imbalanced expression of the acute myeloid leukemia-1A (AML-1A) and AML-1B transcription factors. We hypothesized that the increased expression ratios of AML-1A to AML-1B also induced abnormal expression of other hematopoietic and bone-specific genes that contribute to the poor prognosis of MM patients with high levels of MIP-1 alpha. We found that interleukin-3 (IL-3) was also induced by the imbalanced AML-1A and AML-1B expression in myeloma. IL-3 mRNA levels were increased in CD138+ purified myeloma cells with increased AML-1A-to-AML-1B expression from MM patients, and IL-3 protein levels were significantly increased in freshly isolated bone marrow plasma from MM patients (66.4 +/- 12 versus 22.1 +/- 8.2 pg/mL; P = .038). IL-3 in combination with MIP-1 alpha or receptor activator of nuclear factor-kappa B ligand (RANKL) significantly enhanced human osteoclast (OCL) formation and bone resorption compared with MIP-1 alpha or RANKL alone. IL-3 stimulated the growth of interleukin-6 (IL-6)-dependent and IL-6-independent myeloma cells in the absence of IL-6, even though IL-3 did not induce IL-6 expression by myeloma cells. These data suggest that increased IL-3 levels in the bone marrow microenvironment of MM patients with imbalanced AML-1A and AML-1B expression can increase bone destruction and tumor cell growth.Blood 04/2004; 103(6):2308-15. · 9.90 Impact Factor -
Article: AML-1A and AML-1B regulation of MIP-1alpha expression in multiple myeloma.
[show abstract] [hide abstract]
ABSTRACT: Macrophage inflammatory protein-1alpha (MIP-1alpha) is produced in high concentration by multiple myeloma (MM) cells in about 70% of patients, and MIP-1alpha levels correlate with their disease activity. Patients who have high levels of MIP-1alpha have a poor prognosis. Furthermore, blocking MIP-1alpha expression in an in vivo model of human MM profoundly decreases both tumor burden and bone destruction, suggesting that MIP-1alpha is an important mediator of MM bone disease. Therefore, to analyze the regulation of MIP-1alpha production in MM, we cloned the human MIP-1alpha promoter and characterized the transcription factor (TF) motifs that control MIP-1alpha expression in MM cells. The proximal region of MIP-1alpha promoter was composed of 2 sets of identical transcription regulatory regions consisting of GATA-2(+) AML-1(+) C/EBPalpha motifs. Since 2 alternatively spliced variants of the acute myeloid leukemia-1 (AML-1) class of TFs can bind the AML-1 region, AML-1A and AML-1B, the relationship between the expression levels of AML-1A or AML-1B in MM cells and their capacity to express MIP-1alpha was examined. AML-1A mRNA was relatively overexpressed compared with AML-1B in MM cell lines that produced high levels of MIP-1alpha (> 1 ng/mL per 10(6) cells per 72 hours), but AML-1A was not increased in MM cell lines that expressed less than 200 pg/mL MIP-1alpha. More importantly, the ratio of AML-1A to AML-1B mRNA levels was also increased in 3 of 3 highly purified myeloma cells from patients with MM who expressed increased amounts of MIP-1alpha. The ratio of AML-1A to AML-1B mRNA in patients with MM was 8-fold higher than in healthy controls. Transduction of AML-1B into the MM-derived MM.1S and ARH-77 cells totally blocked MIP-1alpha production, while AML-1A did not further increase the already high levels of MIP-1alpha produced by these cells. Taken together, these data demonstrate that in patients with MM who produce increased concentrations of MIP-1alpha, the relative level of AML-1B is significantly decreased compared with healthy controls. The data suggest that strategies that enhance AML-1B expression or decrease AML-1A in MM cells may be beneficial therapeutically.Blood 05/2003; 101(10):3778-83. · 9.90 Impact Factor
Top co-authors
Top Journals
- British Journal of Haematology (3)
- Blood (3)
- Blood (2)
- Gynecologic Oncology (1)
- Experimental Hematology (1)
