bluuebunny/crossref_metadata_2025_split huggingface dataset:
Disruption of the Crosstalk CXCL12/CXCR4 Chemotactic Pathway To Enhance Melphalan-Induced Apoptosis in Multiple Myeloma Cell Lines.
Authors: Saad Ayman A. , Fortney James , Wang Lin , O’Leary Heather , Gibson Laura , Ericson Solveig 
Published: October 2019

Abstract
INTRODUCTION:
Multiple myeloma cells display functional CXCR4 chemokine receptor that stimulates the migration of these cells toward their natural ligand, CXCL12 (stromal-derived factor, SDF-1a). CXCL12 is secreted by bone marrow stroma. Consistent with their CXCR4 expression, myeloma cells home to the marrow microenvironment, where adhesive interactions promote growth, survival, and confer cell adhesion-mediated drug resistance.
METHODS
U266-B1 cells (ATCC myeloma cell line) were pre-treated with recombinant CXCL12 for 30 minutes prior to the addition of melphalan for up to 72 hours. Both melphalan and CXCL12 were added at 24 hour intervals. Cell lines alone and cell lines with only melphalan or only CXCL12 were used as controls. We have also tested the influence of adding AMD3100, a reversible inhibitor of CXCR4, on myeloma cell survival. U266-B1 cells in media alone were pre-treated with AMD3100 for 24 hours prior to treatment with melphalan for 16 hours. Cell viability following treatment was quantified by flow cytometry assay using Annexin-V-FITC staining. Western blot analysis was used to quantify the apoptotic activity of the cell lines using 4 apoptotic markers: PARP (poly ADP-ribose polymerase), caspase-3, Bcl-2, and Mcl-1.
RESULTS:
Recombinant CXCL12 conferred a protective effect to myeloma cell lines during melphalan treatment. This effect was more pronounced at 72 hours of treatment. Western blot analysis showed diminished expression of the apoptotic markers, cleaved PARP (poly ADP-ribose polymerase) and active caspase-3 in the melphalan-treated cell lines with prior exposure to CXCL12. Additionally, pretreatment with AMD3100 resulted in enhanced apoptosis following melphalan treatment.
CONCLUSION:
Our data showed that CXCL12, a naturally occurring cytokine secreted by bone marrow stromal cells confers a protective effect on myeloma cells against apoptosis. Disruption of this effect by AMD3100 resulted in enhanced melphalan-induced apoptosis of myeloma cells. We are continuing to study this effect with the potential future utility of AMD3100 as a melphalan chemo-sensitizer in the treatment of multiple myeloma.
Expression of Soluble Syndecan-1 or Heparanase by Myeloma Cells Enhances Levels of Angiogenic Growth Factors Present in Endothelial Cells.
Authors: Yang Yang , Frith Ashley Elizabeth , Theus Allison , Macleod Veronica , Sanderson Ralph D. 
Published: October 2019

Abstract
Multiple myeloma is a devastating cancer with a high rate of morbidity and mortality. Our previous in vivo studies demonstrate that both shed syndecan-1 and heparanase can promote myeloma tumor growth, metastasis and angiogenesis. To examine the mechanism underlying this enhanced angiogenesis, human umbilical vein endothelial cells (HUVEC) were cocultured with cells of the CAG myeloma cell line (vector-only controls, CAGcontrol) or CAG cells engineered to express high levels of either soluble syndecan-1 ectodomain (CAGssyn1 ) or heparanase ( CAGHPSE ). After coculture for 48 hours, levels of angiogenic growth factors present in the endothelial cells were examined. The goal was to determine if expression of either soluble syndecan-1 or heparanase by CAG myeloma cells altered growth factor levels relative to those present when control CAG cells were used. Co-culture with CAGssyn1 or CAGHPSE cells did not enhance endothelial levels of FGF-2, while levels of hepatoma-derived growth factor (HDGF) and hepatocyte growth factor (HGF) were elevated in endothelia growing in the presence of CAGssyn1 cells but not CAGHPSE cells or CAGcontrol cells. However, VEGF levels present in endothelial cells were substantially enhanced by the presence of CAGssyn1 (1.9-fold increase) or CAGHPSE cells (1.6-fold increase). Surprisingly, levels of VEGF in conditioned media of cocultures containing either CAGssyn1 or CAGHPSE cells was low. In contrast, when cultured in the absence of HUVECs, VEGF levels were elevated in conditioned media of both CAGssyn1and CAGHPSE cells. Addition of this conditioned media containing high levels of VEGF to HUVECs growing in the absence of CAG cells did not result in an elevation of VEGF levels in the endothelial cells. Together, these experiments suggest that VEGF expression is upregulated in CAG cells expressing high levels of shed syndecan-1 or heparanase and that VEGF becomes associated with the endothelial cells only when they are cultured in the presence of the myeloma cells. This cross-talk between myeloma and endothelial cells may lead to the enhanced angiogenesis that occurs in vivo in tumors formed by myeloma cells producing high levels of shed syndecan-1 and/or heparanase.
CS1: A Potential New Therapeutic Target for the Treatment of Multiple Myeloma.
Authors: Hsi Eric D. , Steinle Roxanne , Balasa Balaji , Draksharapu Aparna , Shum Benny , Huseni Marukh , Powers David , Nanisetti Amulya , Williams Marna , Vexler Vladimir , Hussein Mohamad , Afar Daniel 
Published: October 2019

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.
A Novel, Mercaptoketone-Based HDAC Inhibitor, KD5170 Exerts Marked Inhibition of Osteoclast Formation and Anti-Myeloma Activity In Vitro.
Authors: Feng Rentian , Hager Jeffrey H. , Hassig Christian A. , Phar Shawn A. Scranton , Payne Joseph E. , Mapara Markus Y. , Roodman David , Lentzsch Suzanne 
Published: October 2019

Abstract
Multiple Myeloma (MM) is characterized by the malignant proliferation of plasma cells and high osteoclast (OCL) activity resulting in increased bone destruction and the development of lytic lesions. Ideally, novel therapeutic agents directed at MM should not only target the myeloma cell, but also OCL activity. Multiple, chemically distinct, Histone Deacetylase (HDAC) inhibitors have shown promising anti-myeloma activity in pre-clinical studies. The majority of the HDAC inhibitors in clinical development employ either benzamide or hydroxamate chemistry. Through an uHTS biochemical screen of 600,000 compounds and subsequent medicinal chemistry efforts, a novel mercaptoketone series of HDAC inhibitors has been developed. The most potent compounds in this series exhibit nanomolar activity in both biochemical and cell-based assays. To determine the clinical potential of this series in treating MM we have profiled the lead compound, KD5170 in assays that monitor osteoclastogenesis and proliferation and apoptosis of MM cells.
To evaluate the effects of KD5170 on the formation of OCL from mononuclear hematopoietic precursors, we utilized a human bone marrow culture system from MM patients to generate OCLs by in vitro RANKL/M-CSF stimulation. KD5170 treatment resulted in a significant dose dependent (0.5–8 10−6M) inhibition of osteoclast formation. In addition, RPMI-8226 cell proliferation was significantly suppressed by KD5170 at 3 10−6M as measured by [3H]-Thymidine-incorporation. Furthermore, we observed that KD5170 induced dose- (0.05–1 10−6M) and time-dependent (2–24h) apoptosis of U266 MM cells, as measured by Hoechst/PI double staining to identify distinct stages of apoptosis and to differentiate between apoptotic and necrotic cell death. Significantly, less than 5% of the cells were necrotic (PI-positive) indicating active engagement of the apoptotic pathway. KD5170 treatment (1 10−6M, 72 h) also markedly decreased the viability of primary CD138+ bone marrow cells from MM patients, as determined by trypan blue exclusion. In contrast, the viability of CD138− and mononuclear bone marrow cells from MM patients and normal healthy donors were unaffected, suggesting targeted selectivity.
Our studies identify KD5170 as a promising new HDAC inhibitor that inhibits both osteoclast formation as well as the proliferation of MM cells. Furthermore, pronounced anti-proliferative activity of KD5170 on the MM cell line U266, suggests that a subset of MM may be the ideal target of this agent. U266 harbors a translocation involving 11q13 raising the possibility that this chromosomal alteration and Cyclin D1 dysregulation may have a role in mediating KD5170 sensitivity and as such will be a focus of future studies.
Effects of a Novel Histone Deacetylase Inhibitor, PXD101, When Used as Monotherapy or in Combination with Bortezomib on Tumor Growth in Mouse Models of Human Multiple Myeloma.
Authors: Campbell Richard A. , Sanchez Eric , Chen Haiming , Turker Lauren , Trac Olivia , Li Mingjie , Shalitin Dror , Gordon Melinda S. , Pang Shen , Bonavida Benjamin , Said Jonathan , Jeffers Michael , Qian Xiaozhong , Lichenstein Henri S. , Berenson James R. 
Published: October 2019

Abstract
Histone deacetylase (HDAC) inhibitors represent a new mechanistic class of anti-cancer therapeutics that inhibit HDAC enzymes and have been shown to have anti-proliferative effects in cancer cells (including drug resistance subtypes), induce apoptosis, inhibit angiogenesis, and sensitize cancer cells when combined with other available anti-cancer therapies. PXD101 is a novel investigational small molecule drug that selectively inhibits HDAC enzymes. In recent preclinical studies, PXD101 has been shown to have the potential to treat a wide range of solid and hematological malignancies either as a monotherapy or in combination with other active agents. In this study, we evaluated the activity of PXD101 on multiple myeloma samples when used as monotherapy or in combination with the proteasome inhibitor bortezomib. In vitro experiments indicated that PXD101 pretreatment (20 mM; 3h) sensitized RPMI-8226 human multiple myeloma cells to subsequent bortezomib exposure (5 nM; 72h). To examine PXD101 and bortezomib in vivo, two mouse models of human multiple myeloma were utilized (LAGλ-1 and LAGκ-1B). LAGλ-1 was generated from a patient resistant to melphalan therapy and LAGκ-1B from a patient who progressed on bortezomib treatment (Campbell et al, International Journal of Oncology 2006). SCID mice were implanted with LAGλ-1 or LAGκ-1B tumor fragments into the left superficial gluteal muscle. Tumors were allowed to grow for 14 days at which time human IgG levels were detectable in the mouse serum, and mice were randomly assigned into treatment groups. Groups consisted of Vehicle only, PXD101 alone (40 mg/kg), bortezomib alone (0.5 mg/kg), or PXD101 (40 mg/kg) + bortezomib (0.5 mg/kg). In one cohort, PXD101 and bortezomib were administered twice weekly (M, Th) and in another cohort PXD101 was administered 5 days a week (M-F) and bortezomib twice weekly (M, Th). When administered, PXD101 was given i.p twice daily and bortezomib once daily intravenously. The results of these animal experiments will provide preclinical information on the activity of PXD101 monotherapy and PXD101/bortezomib combination therapy on drug-resistant myeloma samples, and may help to define the optimal schedule for potential clinical evaluation of this drug combination.
Total Therapies (TT) for Newly Diagnosed Patients with Multiple Myeloma (MM): Significant Benefit in High-Risk Disease with Cytogenetic Abnormalities (CA) over the Course of 17 Years.
Authors: van Rhee Frits , Bolejack Vanessa , Anaissie Elias , Tricot Guido , Hollmig Klaus , Zangari Maurizio , Pineda-Roman Mauricio , Mohiuddin Abid , Hoering Antje , Crowley John , Barlogie Bart 
Published: October 2019

Abstract
Background: In 1989, TT with tandem autotransplants (AT) was developed - in analogy to St. Jude’s TT program for childhood ALL - to advance the treatment outcome of MM patients. New agents and treatment principles were introduced as we moved from TT1 to T2 to TT3, mainly to address the inferior outcome in high-risk patients, introducing post-AT consolidation chemotherapy and thalidomide in TT2 and treatment in between chemotherapy cycles/transplants plus bortezomib in TT3. The consistently high-risk associated with the presence of metaphase cytogenetic abnormalities (CA) had been recognized in TT1. We now examine the benefit of intensifying therapy over time in patients with and without CA.
Patients and Methods: According to our MM data base, 979 newly diagnosed patients had at least 1 AT; 181 patients were enrolled prior to 1999 and 798 patients thereafter (566 on TT2 and 232 on TT3). Univariate and multivariate analyses were performed to examine the impact on overall survival (OS) of time of protocol enrollment in the context of pre-treatment laboratory parameters
Results: Pre-treatment features of the 2 cohorts were comparable in terms of frequencies of CA and serum levels of B2M, CRP and creatinine. The recent cohort (after 1999) had higher percentages of patients aged >65yr (22% vs 8%) and with LDH>190U/L (32% vs 7%, p<.001) but lower proportions with albumin<3.5g/dL (2% vs 9%, p<.001) and Hb<10g/dL (19% vs 50%, p<.001). Median OS was superior in the 798 patients enrolled after 1999 compared to the 181 prior to 1999 (not reached vs 72mo, p=.007). Other univariately significant adverse features included CA, B2M>=3mg/L, CRP>=6mg/L (all p<.001); age >=65yr (p=.002), creatinine>1.5mg/dL (p=.007), albumin<3.0g/dL (p=.018) and male gender (p=.049). On multivariate analysis, the following adverse variables entered the model: CA (HR=2.19, p<.001), B2M>=3mg/L (HR=1.79, p<.001), CRP>=6mg/L (HR=1.48, p=.002), age >=65yr (HR=1.44, p=.015), enrollment pre-1999 (HR=1.38, p=.026) and male gender (HR=1.27, p=.047). Importantly, a significant benefit was apparent for the one-third of patients with CA who received TT post-1999 (median not reached versus 4yr, p=.02), whereas there was a trend apparent for those without CA (Figure).
Conclusion: Pursuit of the TT approach has indeed improved the outcome of the one-third of high-risk patients with CA, with a 5-yr OS rate of ~55% post-1999 versus 35% pre-1999.
OS By Enrollment Periods  Total Therapies 1/2/3 OS By Enrollment Periods  Total Therapies 1/2/3
Melphalan (M), Prednisone (P) and Lenalidomide (R) Combination (MPR) for Newly Diagnosed Multiple Myeloma Patients Who Are Not Candidates for Stem Cell Transplantation.
Authors: Roy Vivek , Leif Bergsagel P. , Jacob Allred , Philip Greipp R. 
Published: October 2019

Abstract
Lenalidomide is an orally active immunomodulatory drug effective in the treatment of multiple myeloma. We evaluated the toxicity and efficacy of MPR combination in a phase I/II study. Patients with newly diagnosed symptomatic multiple myeloma who were not candidates or refused stem cell transplantation were eligible. Treatment consisted of M and P on days 1 – 4 and R on days 1 – 21 in a 28 day cycle. All patients received aspirin 325 mg a day. Routine antibacterial prophylaxis was not used. Patients were accrued in cohorts of 3 at dose level 0 (M 5mg/m 2/d P 60 mg/m2/d R 10 mg/d) and level 1 (M 8mg/m2/d P 60 mg/m2/d R 10 mg/d). Patients were followed for at least 2 cycles to assess Dose Limiting Toxicity (DLT). G/GM-CSF use was not allowed in the first 2 cycles unless DLT had occurred. DLT was defined as occurrence of at least grade (G) 4 hematologic toxicity, G3 febrile neutropenia, or G 3 non-hematologic toxicity in the first two cycles. Failure to start the next cycle within 7 days of day 1 due to toxicity also constituted DLT.
Results: 7 patients have been accrued (4 at dose level 0 {one patient had to be replaced} and 3 at dose level 1). 4 were males. ECOG performance status was 0 or1 (2 and 4 patients). Median age was 74 yrs, range 72 – 85. Between 3 and 10 cycles (median 4) have been administered at the time of this reporting. The following G3 or higher toxicities were encountered and considered at least possibly related to treatment: 2 patients at level 0 had G3 neutropenia. Of the three patients at dose level 1, there was 1 G4 neutropenia, 1 G4 thrombocytopenia, 1 G3 hyperglycemia and 1 G4 vascular access device related thrombosis. Responses were defined by EBMT/IBMTR criteria. 1 had a complete remission (after 3 cycles), 4 had partial remission (at least 50% reduction in monoclonal protein) and 1 had minimal response (after 3 cycles). Due to 3 DLT’s in dose level 1, dose level 0 was chosen for phase II of the study.
Conclusion: M 5 mg/m2, P 60 mg/m2 and R 10 mg combination is well tolerated and appears effective in patients with multiple myeloma. These results are similar to the experience reported by Palumbo et al (Blood2005, 106(11):abst 785) although a stricter definition of DLT was used in our study. Escalation of R dose in combination with M 5 mg/m2, P 60 mg/m2 may be possible and improve responses. Updated data will be presented.
Deep Vein Thrombosis in Myeloma: Estimate of Prevelance and Recommendations for Therapy Based upon a Survey of Members of the International Myeloma Working Group (IMWG).
Authors: Durie Brian G.M. , Richardson Paul , Palumbo Antonio , Dimopoulos Meletios A. , Cavo Michele , Hajek Roman , Joshua Douglas E. , Shimizu Kazuyuki , Tricot Guido J. , Gertz Morie , Tosi Patrizia , Vesole David H. , Hussein Mohamad A. , Ludwig Heinz , Goldschmidt Hartmut , Miguel J.F. San , Sonneveld Pieter , Rajkumar S. Vincent 
Published: October 2019

Abstract
Purpose: Deep vein thrombosis (DVT) is increasingly recognized as a major complication of thalidomide (T; Thal) and lenalidomide (R; Rev) based therapy for multiple myeloma. Estimated incidence varies widely in the literature. There is no consensus on specific risk factors, indications for thromboprophylaxis or the agent of choice for DVT prophylaxis. The purpose of this study was to develop a consensus among members of the IMWG.
Patients and Methods: A survey was electronically mailed to 67 IMWG members on July 21, 2006 and consisted of 24 multiple-choice questions.
Results: Twenty-three IMWG members (34%) sent in their responses by the cut-off date. All (100%) felt that DVT was an important question, but most (95%) did not avoid Thal/Rev based therapy because of the DVT risk. Overall results are summarized in the Table below. A majority of physicians felt that concomitant therapy with high dose dexamethasone (90% of physicians), alkylators (55%), doxorubicin/liposomal doxorubicin (90%), and erythropoietin (75%) increase the risk of DVT associated with Thal or Rev based therapy. Aspirin (81 mg or 325 mg per day) was the preferred choice of prophylaxis when necessary. However, 65% of respondents preferred warfarin to a therapeutic INR or LMW heparin if either doxorubicin or liposomal doxorubicin was added to the regimens. Most (95–100%) felt that DVT prophylaxis was not indicated for: VAD, MP, bortezomib +/− dexamethasone regimens. Seventy-five percent felt it to be safe to resume therapy with Thal/Rev after therapeutic anticoagulation. Most (95%) believed randomized trials were needed.
Conclusion: DVT is recognized as a major clinical problem associated with Thal/Rev containing regimens. Most respondents felt that the DVT risk did not warrant any prophylaxis when either Thal or Rev were used as single agents. Aspirin was the preferred form of DVT prophylaxis for most Thal/Rev containing regimens, except when doxorubicin/liposomal doxorubicin or melphalan were added. Additional responses will be analyzed both electronically and by conference call prior to the meeting.
Therapy Estimated incidence of DVT (% respondents) Choice of thromboprophylaxis (% respondents) Single agent thal <5% (61%) None (65%) Single agent Rev <5% (80%) None (65%) Thal-Dex 10–20% (52%) Aspirin (60%) Rev-Dex 10–20% (48%) Aspirin (60%) MPT 10–20% (65%) Aspirin (40%) R-MP 5–10% (57%) Aspirin (70%)