bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular Classification of Multiple Myeloma: A Distinct Transcriptional Profile Characterizes Patients Expressing CCND1 and Negative for 14q32 Translocations.
Authors: Agnelli Luca , Bicciato Silvio , Mattioli Michela , Fabris Sonia , Intini Daniela , Verdelli Donata , Baldini Luca , Morabito Fortunato , Callea Vincenzo , Zanella Alberto , Deliliers Giorgio Lambertenghi , Lombardi Luigia , Neri Antonino 
Published: April 2020

Abstract
The deregulation of CCND1, CCND2 and CCND3 genes represents a common event in multiple myeloma (MM), being at least one of them deregulated in almost all MM tumors. A recently proposed TC classification1 grouped MM patients into five classes on the basis of their cyclins D expression profiles and the presence of the main translocations involving the immunoglobulin heavy-chain (IGH) locus at 14q32. The aim of our study was to identify the putative transcriptional fingerprints associated with the deregulation of the different D-type cyclins and the presence of IGH translocations. The cyclin D expression levels obtained by high-density oligonucleotide microarray analysis of purified plasma cells from 50 MM cases were used to stratify the samples into the five TC classes, along with the molecular characteristics. The cyclin D expression data were validated by means of real-time quantitative PCR analysis; fluorescence in-situ hybridization was used to investigate the cyclin D loci arrangements, and to detect the main IGH translocations and the chromosome 13q deletion. A multi-class classification analysis was performed on the gene expression data and used to identify the transcriptional fingerprints of the 5 TC groups. 112 probe sets were selected as characterizing the TC1, TC2, TC4 and TC5 groups, whereas the TC3 samples showed heterogeneous phenotypes and no marker genes. In particular, TC1, TC4 and TC5 groups were characterized by the molecular signatures associated with the primary IGH translocations target genes. The TC2 group, showing significantly extra copies of the CCND1 locus (P=5.9×10−3) and neither IGH translocations nor the chromosome 13q deletion (P=1.7×10−3), was characterized by the overexpression of 30 genes, mainly involved in protein biosynthesis at translational level. Among the most specifically modulated transcripts within the group we identified a novel gene containing a BTB/POZ domain, typical of many zinc finger transcription factors and associated with transcriptional repression activity. A meta-analysis performed on two publicly available MM datasets, containing almost 250 cases, validated the identified gene expression signatures with a global classification rate (indicating the correct prediction of the TC class for the independent set) of 86% and 90%, respectively. Our data contribute to the understanding of the molecular and biological features of distinct MM subtypes; the identification of a distinctive gene expression pattern in TC2 patients may improve risk stratification and indicate novel therapeutic targets.
Aberrant Autocrine and Paracrine CD40L Signaling Promotes Primary Myeloma Cell Survival and Attenuates Bortezomib-Induced Apoptosis.
Authors: Chen-Kiang Selina , Ely Scott , Di Liberto Maurizio , Wu Kaida , Shaughnessy John , Moore Malcolm , Niesvizky Ruben , Hatada Eunice 
Published: April 2020

Abstract
In multiple myeloma (MM), impaired apoptosis is critical for clonal expansion of malignant MM cells in the bone marrow (BM), although the precise underlying mechanism has not been defined. During physiologic plasma cell differentiation, clonal expansion of antigen-activated B cells in the germinal center requires CD40 signalling, which mediates CD40L signals from activated T cells to promote B cell activation and survival. Terminal differentiation of plasma cells from activated B cells is then accompanied by a progressive reduction of CD40 expression, suggesting that the life span of normal plasma cells may be limited by the loss of CD40L signalling. Here we show that CD40L and CD40 are both aberrantly expressed in primary BM MM cells, but not in normal BM plasma cells, their likely normal counterparts. CD40L is also copiously expressed in multiple cell types in myeloma and normal bone marrows, indicating that autocrine and paracrine CD40L signalling may prolong the survival of MM cells in the bone marrow microenvironment. Supporting this hypothesis, disruption of CD40L signalling by an antagonizing CD40L antibody markedly accelerates apoptosis of BM MM cells ex vivo. In the majority of MM cases (N=50), CD40 is expressed at either greater than 90% of BM MM cells or lower than 30% of BM MM cells in vivo, but rarely in between. However, there is no apparent correlation between the frequency of CD40 expression in BM MM cells in vivo and immunoglobulin isotype or treatment history, including bortezomib therapy. Ex vivo, the level of CD40 expression in BM MM cells is enhanced in response to bortezomib, which rapidly activates CD40 transcription. Moreover, killing of primary BM MM cells by bortezomib ex vivo is attenuated by CD40L signalling, at least in part through sustaining NF-?B activation that is required for MM cell survival. Together, our findings suggest that autocrine and paracrine CD40L signalling is critical for the survival of MM cells in the bone marrow and may contribute to the development of drug resistance.
A Multicenter, Single-Arm, Open-Label Study To Evaluate the Efficacy and Safety of Single-Agent Lenalidomide in Patients with Relapsed and Refractory Multiple Myeloma; Prelininary Results.
Authors: Richardson Paul , Jagannath Sundar , Hussein Mohamad , Berenson James , Singhal Seema , Irwin David , Williams Stephanie F. , Bensinger William , Badros Ashraf Z. , Vescio Robert , Kenvin Laurie , Yu Zhinuan , Olesnyckyj Marta , Faleck Herbert , Zeldis Jerome , Knight Robert , Anderson Kenneth C. 
Published: April 2020

Abstract
INTRODUCTION: Lenalidomide (REVLIMID®; CC-5013) is a novel, orally active immunomodulatory drug under investigation for the treatment of multiple myeloma (MM). Phase 1 dose-escalation studies in patients (pts) with relapsed and refractory MM determined that the maximum tolerated dose (MTD) of lenalidomide was 25 mg/day, based upon myelosuppression encountered beyond 28 days, which was manageable with growth factor support and dose reduction. In a multicenter phase 2 study to determine optimal dose and schedule, 102 pts with relapsed or refractory MM were randomized to receive lenalidomide at either 15 mg bid (n=34) or 30 mg qd (n=68), for 21 days every 4 wks. Both treatment arms showed significant activity with manageable toxicity. An increased incidence of cytopenia was noted in the 15-mg bid group and thus the 30 mg qd schedule was taken forward.
METHODS: The objective of this multicenter, phase 2, open-label study (CC-5013-MM-014) was to further evaluate the effectiveness and safety of single-agent lenalidomide administered at a dose of 30 mg qd for 21 days every 28 days (28-day cycle) in pts with relapsed and refractory MM. Eligible patients included those who had received prior thalidomide, bortezomib, or SCT.
RESULTS: 222 pts were enrolled into the study. All patients had received at least 2 prior anti-myeloma treatments, including bortezomib (41%), thalidomide (80%), and SCT (44%). Table 1 shows Best Response data, excluding patients in whom responses were not evaluable (n=10). Partial response or better occurred in 25% of patients and SD or better in 71%. Time to Progression was a median of 22.4 wks (range 1.8– 66 wks). The median survival has not been reached (the lower bound of the 95% CI exceeds 15 months). The most common treatment-related AEs (those reported in ≥10% of patients overall) included upper respiratory tract infection, neutropenia and thrombocytopenia. AEs that most frequently led to dose reduction or interruption by percentage of cases were neutropenia (40%), thrombocytopenia (23%), fatigue (5%), and anemia (5%).
CONCLUSION: Oral lenalidomide in relapsed and refractory MM patients achieved PR+CR in 25%, stable disease or better in 71%, a median TTP of approximately 6 months and a median survival that has not been reached. Toxicity has been manageable with a very low incidence of DVT and minimal treatment-emergent neuropathy.
Table 1. Best Response Best Response* n (%) *Excluding patients not evaluable (n=10); CR=complete response and PR=partial response (EBMT criteria) ≥PR (CR + PR) 53 (25) Stable disease 152 (71)
BCL6 Attenuates DNA Damage Sensing in Normal and Malignant B-Cells by Directly Repressing ATR.
Authors: Ranuncolo Stella M. , Polo Jose M. , Dierov Jamil , Shaknovich Rita , Carroll Martin , Melnick Ari M. 
Published: April 2020

Abstract
The BCL6 (B-Cell-Lymphoma-6) transcriptional repressor is a critical oncogene in B-cell lymphomas and is required for establishment of germinal centers by normal B-cells. However, the mechanisms by which BCL6 licenses germinal center formation and lymphomagenesis are unknown. To characterize this mechanism we identified BCL6 target genes by expression arrays and high throughput chromatin immunoprecipitations. Remarkably, a number of these target genes were critical mediators of DNA damage sensing checkpoints including ATR and p53. Therefore, we hypothesized that BCL6 could attenuate DNA damage sensing by silencing these genes, which is likely a critical attribute for survival and proliferation of germinal center B-cells cells undergoing somatic hypermutation (SHM) and class switch recombination (CSR). Accordingly, we found that expression of BCL6 in normal diploid fibroblasts could block cellular sensing of DNA damage as demonstrated by loss of histone 2AX (H2AX) phosphorylation and delayed repair of double strand breaks. Repression of ATR (but not p53 or other targets) was required for this phenotype. This is a physiological effect since the same result was observed when BCL6 was expressed in purified primary human tonsilar mature B-cells. Reciprocally, shRNA knockdown of BCL6 in B-cell lymphomas rescued repression of ATR, enhanced H2AX phosphorylation and accelerated repair of double strand breaks, independent of the status of p53. shRNA knockdown of BCL6 caused a marked increase of apoptosis in lymphoma cells in response to DNA damage, due to restored DNA damage checkpoint functions. Importantly, BCL6 knockdown had an identical effect on ATR levels, H2AX phosphorylation, DNA damage, and survival in purified primary human germinal center centroblasts. These results suggest that a major role of BCL6 in germinal center formation is to attenuate cellular response to DNA damage occurring as a byproduct of CSR and SHM. The same mechanism also seems to be required for lymphomagenesis, since we observed that sustained BCL6 expression in human primary mature B-cells leads to aberrant survival properties and genomic instability. Moreover, BCL6 blockade using a specific inhibitor molecule designed by our lab induces apoptosis in lymphoma cells and synergizes with DNA damaging agents. Therefore, we have identified a critical mechanism of action of the BCL6 oncoprotein in normal and pathogenic states and show that specific targeting of BCL6 could synergize with chemotherapy drugs for the therapy of B-cell lymphomas.
The Proteasome Inhibitor PR-171 Inhibits Cell Growth, Induces Apoptosis, and Overcomes De Novo and Acquired Drug Resistance in Human Multiple Myeloma Cells.
Authors: Ivancsits Douglas , Nimmanapali Rama , Sun Megan , Shenk Kevin , Demo Susan D. , Bennett Mark K. , Dalton William S. , Alsina Melissa 
Published: April 2020

Abstract
Proteasome inhibitors are a new class of drugs that have shown to be cytotoxic and induce apoptosis in tumor cells, particularly, multiple myeloma (MM). This led to the clinical evaluation and subsequent FDA approval of the proteasome inhibitor, bortezomib, for the treatment of refractory and relapsed multiple myeloma. However, continued occurrence of refractoriness, development of resistance, and the toxicity of bortezomib in treated patients has led to the recent development of novel agents with increased binding efficiency and specificity to the proteasome. PR-171 is a member of the epoxomicin-class of compounds that act as potent and selective irreversible inhibitors of the chymotrypsin-like protease activity of the 20S proteasome resulting in accumulation of ubiquinated proteins and apoptosis of tumor cells (Ming et al., PNAS96:10403). In this study, we evaluated the effects of PR-171 on human MM cells’ survival, proteasome activity and drug resistance. PR-171 induced growth inhibition and apoptosis in the drug sensitive human MM cell lines 8226/S, MM1, H929, and U266, with IC50 values ranging from 9 to 21nM. PR-171 retains activity on cells resistant to melphalan, mitoxantrone, and zarnestra, but has reduced activity on cells resistant to doxorubicin. Pretreatment with verapamil restored sensitivity of the doxorubicin resistant cells (8226/Dox40) to PR-171 back to levels seen in the parental, drug sensitive cell line (8226/S). Proteasome activity was inhibited by PR-171 in the drug sensitive and drug resistant MM cell lines, although much less inhibition was observed in the doxorubicin resistant cells, consistent with the reduced effects of PR-171 on cell viability. In freshly isolated MM cells from patients, PR-171 at doses of 10–250nM induced apoptosis in 9/9 samples tested from both newly diagnosed and relapsed refractory patients. To test the effects of PR-171 on Cell Adhesion Mediated Drug Resistance (CAM-DR), MM cell lines were treated with drug after adhesion to fibronectin. PR-171 at 1–100nM overcomes CAM-DR in 8226/S and H929 cell lines, but not in MM1. The ability of PR-171 to overcome CAM-DR was also seen in primary MM cells from patients in 6 out of 9 samples tested. In summary, we have shown that PR-171 directly inhibits proteasome activity, proliferation, and induces apoptosis in human MM sensitive and resistant cell lines, induces apoptosis in isolated MM cells from newly diagnosed and relapsed refractory patients, and overcomes de novo drug resistance. These studies provide the foundation for clinical investigation of PR-171 to improve the outcome of patients with MM and other hematological malignancies.
R-Etodolac and a Novel Indole-Pyran Structural Analog, SDX-308, Induce Cytotoxicity and Overcome Drug Resistance in Multiple Myeloma.
Authors: Yasui Hiroshi , Hideshima Teru , Neri Paola , Jin Janice , Kiziltepe Tanyel , Shiraishi Norihiko , Ishitsuka Kenji , Laurence Catley P. , Raje Noopur , Podar Klaus , Tassone Pierfrancesco , Chauhan Dharminder , Richardson Paul G. , Leoni Lorenzo M. , Kanekal Sarath , Elliott Gary T. , Munshi Nikhil C. , Anderson Kenneth C. 
Published: April 2020

Abstract
SDX-101, the less toxic R-isomer of the commercially available non-steroidal inflammatory drug R,S-etodolac (Lodine®), lacks COX inhibitory activity and is being investigated in Phase II clinical trials in chronic lymphocytic leukemia. Recently, we reported that R-etodolac, at clinically relevant concentrations, induces potent in vitro cytotoxicity in drug-sensitive and conventional drug-resistant multiple myeloma (MM) cell lines, as well as in primary tumor cells from MM patients. R-etodolac triggers caspase/poly-ADP-ribose polymerase (PARP) cleavage and downregulates of cyclin D1 expression (Yasui et al. Blood 2005). Importantly, R-etodolac at sub-cytotoxic doses upregulates Mcl-1s and synergistically enhances dexamethasone (Dex)-induced caspase-dependent apoptosis in Dex-sensitive MM.1S cells. Combination of R-etodolac with Dex enhances cytotoxicity in Dex resistant OPM1 MM cells and in Dex-resistant patient MM cells in vitro. We further studied the in vivo anti-tumor effect of combined R-etodolac and Dex in SCID mice injected subcutaneously with OPM1 human MM cells. While oral treatment of SCID mice with R-etodolac alone (250 mg/kg/d) or Dex alone (1 mg/kg/d) did not induce any significant reduction of tumor volume compared with control (PBS), the combination of R-etodolac and Dex inhibited tumor growth synergistically (synergism quotient = 1.6) and significantly (p = 0.023), suggesting that R-etodolac may reverse Dex resistance in MM. Finally, we demonstrated that racemic SDX-308, a novel indole-pyran structural analog of etodolac, has 10-fold more potent cytotoxicity than R-etodolac in MM cell lines both sensitive and resistant to conventional therapies, as well as in patient’s MM cells. Moreover, SDX-308, like R-etodolac, can overcome the viability and proliferative enhancing effects of exogeneous IL-6, IGF-1, or bone marrow stroma cells. These combined observations indicate that SDX-308 is a promising more potent second generation analog of R-etodolac for MM therapy. Our data suggest that R-etodolac and its novel analog SDX-308 overcome resistance to some conventional therapeutics used for MM, and provide preclinical rationale to conduct clinical trials of R-etodolac and SDX-308 to treat MM.
Targeting Src- Family Kinase Activation and Downstream Molecular Events To Overcome MM Cell Growth, Survival, and Drug- Resistance.
Authors: Podar Klaus , Tai Yu-Tzu , Abtahi Dean , Raab Marc S. , Yasui Hiroshi , Ishitsuka Kenji , Shiraishi Norihiko , Catley Laurence P. , Sattler Martin , Raje Noopur , Hideshima Teru , Chauhan Dharminder 
Published: April 2020

Abstract
IL-6 induces growth and survival factor in multiple myeloma (MM) via ERK and Akt signaling cascades. Our recent studies difined early signaling events mediating phosphorylation of ERK and Akt-1: specifically, a gp130/Hck- containing complex plays a pivotal role in Hck- mediated phosphorylation of Grb2- associated binder (Gab) family adapter proteins thereby mediating downstream signaling (Podar et al, 2004). We have also shown that IL-6 triggers resistance to dexamethasone via a PI3kinase/ Akt-1 signaling pathway by specific activation of SHP2 phosphatase, withsubsequent blockade of related adhesion focal tyrosine kinase (Chauhan et al, 2000). In the present study we first evaluated AP 23464, a potent adenosine 5′-triphosphate (ATP)- based inhibitor of Src kinase (ARIAD Pharmaceuticals Inc., Cambridge, MA), for its effect on proliferation and survival in MM cells. Our results show that AP23464 markedly inhibits both IL-6- triggered Hck activation and the association of Gab adapter protein Gab1 with SH2- domain containing protein- tyrosine phosphatase - 2 (SHP2). Consequently, AP23464 both inhibited MM cell proliferation, as evidenced by 3H[dT] uptake, and induced apoptosis, evidenced by marked increase in sub-G1 phase cells. In contrast, proliferation of normal donor peripheral blood mononuclear cells remained unchanged. Next we investigated the role of Gab-1- SHP2 association mediating IL-6- induced resistance to dexamethasone, and conversely, the effect of inhibition by AP23464. Specifically, we determined whether IL-6- triggered Gab1- SHP2 binding is required for both RAFTK binding to SHP2 and associated IL-6- mediated dexamethasone resistance in MM cells. Utilizing wild- type Gab1 and SHP2- Gab1 binding mutants, our results show marked reduction in IL-6- triggered SHP2- RAFTK association. Moreover, IL-6- triggered resistance to dexamethasone was markedly inhibited in MM cells transfected with SHP2- Gab1 mutants, but not with wild type- Gab1. Importantly, AP23464 downregulated IL-6- mediated resistance to dexamethasone in a dose- dependent manner. Taken together, the present study shows anti-MM effects of AP23464, including abrogation of IL-6- induced dexamethasone resistance via inhibition of SHP2/ RAFTK- binding to Gab1. These studies provide the preclinical basis for the therapeutic evaluation of AP23464, alone or in combination with dexamethsoneto improve patient outcome in MM.
A Green Tea Polyphenol, Epigallocatechin-3-Gallate, Induces Selective Apoptosis in Multiple Myeloma Cells: Mechanism of Action and Therapeutic Potential.
Authors: Shammas Masood A. , Batchu Ramesh B. , Koley Hemanta , Bertheau Robert C. , Neri Paola , Goyal Raj , Anderson Kenneth C. , Munshi Nikhil C. 
Published: April 2020

Abstract
Epigallocatechin-3-gallate (EGCG), a polyphenol extracted from green tea, induces dose and time dependent cell death in both IL-6-dependent and independent multiple myeloma cell lines and primary patient cells, with minimal or no effect on the growth of normal cells. The cell death is apoptotic as determined by annexin V staining and is not inhibited by IL-6. Evaluation of molecular mechanism of action by gene expression profiling indicated that EGCG had a profound effect on transcription of major regulatory genes involved in distinct pathways controlling cell growth arrest and apoptosis: Exposure of myeloma cells to EGCG induced the expression of: 1) Fas ligand, Fas, and caspase 4, the initiators and mediators of death receptor dependent apoptosis; 2) death-associated protein kinase 2, a multifunctional pro-apoptotic protein kinase; 3) P53-like proteins, p73, p63; 4) CARD10 and CARD14, positive regulators of apoptosis and NF-kappaB activation; and 5) Cyclin-dependent kinase inhibitors, p16 and p18. In a subset of these selected genes, the expression data is also confirmed with western blot analyses. We have also demonstrated that the transcript and protein levels of a metastasis associated laminin receptor 1 are significantly elevated in myeloma cell lines and patient samples compared to normal cells. RNAi mediated inhibition of laminin receptor 1, abrogated EGCG-induced apoptosis in myeloma cells thus indicating that the profound anti-cancer effect of this compound is probably mediated through this receptor. The selective expression of this receptor explains the selective activity of EGCG in multiple myeloma cells without adversely affecting normal cells.
Taken together these data confirm significant and selective anti-cancer activity of EGCG, a natural product, in MM and provides the basis for its clinical evaluation.