Potent antimyeloma activity of the novel bromodomain inhibitors I-BET151 and I-BET762.

The bromodomain and extraterminal (BET) protein BRD2-4 inhibitors hold therapeutic promise in preclinical models of hematologic malignancies. However, translation of these data to molecules suitable for clinical development has yet to be accomplished. Herein we expand the mechanistic understanding of BET inhibitors in multiple myeloma by using the chemical probe molecule I-BET151. I-BET151 induces apoptosis and exerts strong antiproliferative effect in vitro and in vivo. This is associated with contrasting effects on oncogenic MYC and HEXIM1, an inhibitor of the transcriptional activator P-TEFb. I-BET151 causes transcriptional repression of MYC and MYC-dependent programs by abrogating recruitment to the chromatin of the P-TEFb component CDK9 in a BRD2-4-dependent manner. In contrast, transcriptional upregulation of HEXIM1 is BRD2-4 independent. Finally, preclinical studies show that I-BET762 has a favorable pharmacologic profile as an oral agent and that it inhibits myeloma cell proliferation, resulting in survival advantage in a systemic myeloma xenograft model. These data provide a strong rationale for extending the clinical testing of the novel antimyeloma agent I-BET762 and reveal insights into biologic pathways required for myeloma cell proliferation.

Nuclear proteasomes carry a constitutive posttranslational modification which derails SDS-PAGE (but not CTAB-PAGE).

We report that subunits of human nuclear proteasomes carry a previously unrecognised, constitutive posttranslational modification. Subunits with this modification are not visualised by SDS-PAGE, which is used in almost all denaturing protein gel electrophoresis. In contrast, CTAB-PAGE readily visualises such modified subunits. Thus, under most experimental conditions, with identical samples, SDS-PAGE yielded gel electrophoresis patterns for subunits of nuclear proteasomes which were misleading and strikingly different from those obtained with CTAB-PAGE. Initial analysis indicates a novel modification of a high negative charge with some similarity to polyADP-ribose, possibly explaining compatibility with (positively-charged) CTAB-PAGE but not (negatively-charged) SDS-PAGE and providing a mechanism for how nuclear proteasomes may interact with chromatin, DNA and other nuclear components.

Autologous Stem Cell Transplantation Is an Effective Salvage Therapy for Primary Refractory Multiple Myeloma.

High-dose therapy and autologous stem cell transplantation (ASCT) have proven efficacy in patients with multiple myeloma responding well to induction therapy. For those who fail to achieve a stable partial response (PR), the effect of ASCT is unclear. We report on 126 patients identified from a national database, who underwent ASCT having achieved

Clinical drug resistance linked to interconvertible phenotypic and functional states of tumor-propagating cells in multiple myeloma.

The phenotype and function of cells enriched in tumor-propagating activity and their relationship to the phenotypic architecture in multiple myeloma (MM) are controversial. Here, in a cohort of 30 patients, we show that MM composes 4 hierarchically organized, clonally related subpopulations, which, although phenotypically distinct, share the same oncogenic chromosomal abnormalities as well as immunoglobulin heavy chain complementarity region 3 area sequence. Assessed in xenograft assays, myeloma-propagating activity is the exclusive property of a population characterized by its ability for bidirectional transition between the dominant CD19(-)CD138(+) plasma cell (PC) and a low frequency CD19(-)CD138(-) subpopulation (termed Pre-PC); in addition, Pre-PCs are more quiescent and unlike PCs, are primarily localized at extramedullary sites. As shown by gene expression profiling, compared with PCs, Pre-PCs are enriched in epigenetic regulators, suggesting that epigenetic plasticity underpins the phenotypic diversification of myeloma-propagating cells. Prospective assessment in paired, pretreatment, and posttreatment bone marrow samples shows that Pre-PCs are up to 300-fold more drug-resistant than PCs. Thus, clinical drug resistance in MM is linked to reversible, bidirectional phenotypic transition of myeloma-propagating cells. These novel biologic insights have important clinical implications in relation to assessment of minimal residual disease and development of alternative therapeutic strategies in MM.

Graft invariant natural killer T-cell dose predicts risk of acute graft-versus-host disease in allogeneic hematopoietic stem cell transplantation.

Invariant natural killer T (iNKT) cells are powerful immunomodulatory cells that in mice regulate a variety of immune responses, including acute GVHD (aGVHD). However, their clinical relevance and in particular their role in clinical aGVHD are not known. We studied whether peripheral blood stem cell (PBSC) graft iNKT-cell dose affects on the occurrence of clinically significant grade II-IV aGVHD in patients (n = 57) undergoing sibling, HLA-identical allogeneic HSCT. In multivariate analysis, CD4(-) iNKT-cell dose was the only graft parameter to predict clinically significant aGVHD. The cumulative incidence of grade II-IV aGVHD in patients receiving CD4(-) iNKT-cell doses above and below the median were 24.2% and 71.4%, respectively (P = .0008); low CD4(-) iNKT-cell dose was associated with a relative risk of grade II-IV aGVHD of 4.27 (P = .0023; 95% CI, 1.68-10.85). Consistent with a role of iNKT cells in regulating aGVHD, in mixed lymphocyte reaction assays, CD4(-) iNKT cells effectively suppressed T-cell proliferation and IFN-γ secretion in a contact-dependent manner. In conclusion, higher doses of CD4(-) iNKT cells in PBSC grafts are associated with protection from aGVHD. This effect could be harnessed for prevention of aGVHD.

EBMT risk score predicts outcome of allogeneic hematopoietic stem cell transplantation in patients who have failed a previous transplantation procedure.

Increasing numbers of allogeneic hematopoietic stem cell transplantation (allo-SCT) are being performed for patients who have failed a previous allogeneic or autologous SCT. We investigated whether the EBMT risk score could predict outcome after a subsequent allo-SCT. We analyzed prognostic factors in 124 consecutive patients who underwent a second transplantation using an allogeneic donor at our institution. Patients with either a first autologous (N = 64) or first allogeneic (N = 60) SCT were included. Age, disease stage, time interval from diagnosis to transplantation, donor type, and donor-recipient sex combination were used to establish a score from 0 to 7 points, from which 3 groups were identified. The 5-year survival probability decreased from 51.7% for risk scores 0-3 (low, n = 25), to 29.3% for risk score 4 (intermediate, n = 42), and only 10.4% for risk scores 5-7 (high, n = 57), P = .001. We propose that the EBMT risk score can identify patients most likely to benefit from a second transplantation.

Optimizing patient selection for myeloablative allogeneic hematopoietic cell transplantation in chronic myeloid leukemia in chronic phase.

Outstanding results have been obtained in the treatment of chronic myeloid leukemia (CML) with first-line imatinib therapy. However, approximately 35% of patients will not obtain long-term benefit with this approach. Allogeneic hematopoietic stem cell transplantation (HCT) is a valuable second- and third-line therapy for appropriately selected patients. To identify useful prognostic indicators of transplantation outcome in postimatinib therapeutic interventions, we investigated the role of the HCT comorbidity index (HCT-CI) together with levels of C-reactive protein (CRP) before HCT in 271 patients who underwent myeloablative HCT for CML in first chronic phase. Multivariate analysis showed both an HCT-CI score higher than 0 and CRP levels higher than 9 mg/L independently predict inferior survival and increased nonrelapse mortality at 100 days after HCT. CML patients without comorbidities (HCT-CI score 0) with normal CRP levels (0-9 mg/L) may therefore be candidates for early allogeneic HCT after failing imatinib.

Interaction between KIR3DS1 and HLA-Bw4 predicts for progression-free survival after autologous stem cell transplantation in patients with multiple myeloma.

Natural killer (NK) cells exert antimyeloma cytotoxicity. The balance between inhibition and activation of NK-cells played by the inherited repertoire of killer immunoglobulin-like receptor (KIR) genes therefore may influence prognosis. One hundred eighty-two patients with multiple myeloma (MM) were analyzed for KIR repertoire. Multivariate analysis showed that progression-free survival (PFS) after autologous stem cell transplantation (ASCT) was significantly shorter for patients who are KIR3DS1(+) (P = .01). This was most evident for patients in complete or partial remission (good risk; GR) at ASCT. The relative risk (RR) of progression or death for patients with KIR3DS1(+) compared with KIR3DS1(-) was 1.9 (95% CI, 1.3-3.1; P = .002). The most significant difference in PFS was observed in patients with GR KIR3DS1(+) in whom HLA-Bw4, the ligand for the corresponding inhibitory receptor KIR3DL1, was missing. Patients with KIR3DS1(+) KIR3DL1(+) HLA-Bw4(-) had a significantly shorter PFS than patients who were KIR3DS1(-), translating to a difference in median PFS of 12 months (12.2 vs 24 months; P = .002). Our data show that KIR-human leukocyte antigen immunogenetics represent a novel prognostic tool for patients with myeloma, shown here in the context of ASCT, and that KIR3DS1 positivity may identify patients at greater risk of progression.

Factors influencing the outcome of a second autologous stem cell transplant (ASCT) in relapsed multiple myeloma: a study from the British Society of Blood and Marrow Transplantation Registry.

Autologous stem cell transplant as primary (first ASCT) therapy in multiple myeloma (MM) is standard practice. The role of a second ASCT as management of relapsed disease remains uncertain. We conducted a retrospective case-matched control analysis on patients (n = 106) who underwent a second ASCT compared with conventional chemotherapy (CCT) as for relapsed MM. The median age was 53 years (range: 26-75) and median follow-up 48 months (range: 8, 136). The cumulative incidence of 1 and 5 years nonrelapse mortality (NRM) was 7% (95% confidence interval [CI] 3%-13%) and 12% (95% CI 7%-19%), with a second ASCT inducing a greater partial remission (PR) rate of 63%. The 4-year overall survival (OS) rate was 33% (95% CI 24%-45%). Factors associated with improved OS and progression-free survival (PFS) included younger age (<55 years), ß(2)MG <2.5 mg/L at diagnosis, a remission duration of >9 months from first ASCT, and a greater PR in response to their first ASCT. In a matched-cohort analysis with patients receiving conventional chemotherapy (CCT), the same factors were associated with improved OS, with the exception of a longer remission duration (>18 months) from first ASCT. Second ASCT in relapsed MM is associated with superior OS and PFS compared with CCT, offering a potential consolidative option for selected patients.

Humoral and cellular immunity to primary H1N1 infection in patients with hematologic malignancies following stem cell transplantation.

Limited data are available on immunologic responses to primary H1N1 infection in patients with hematologic malignancies. We present a prospective, case-surveillance study of such patients with real-time polymerase chain reaction (RT-PCR) confirmed H1N1-influenza who presented to our institution between September 2009 and January 2010. Ninety-two patients presented with influenza-like symptoms, and 13 had H1N1 infection confirmed by RT-PCR, including 4 allogeneic stem cell transplant recipients (1 with acute myelogenous leukemia, 1 with chronic lymphoblastic leukemia [CLL], 1 with non-Hodgkin lymphoma, and 1 with chronic myelogenous leukemia), 5 patients with multiple myeloma following autologous stem cell transplantation, 1 patient with multiple myeloma perimobilization, 2 patients with NHL post chemotherapy, and 1 patient with CLL. All 13 patients required hospitalization. Six (43%) were admitted to the intensive care unit (ICU), of whom 4 (67%) died. We evaluated B cell and T cell responses to H1N1 infection prospectively in these patients compared with those in 4 otherwise healthy controls. Within 12 weeks of diagnosis, only 6 of 11 patients developed seropositive antibody titers as measured by hemagglutination-inhibition or microneutralization assays, compared with 4 of 4 controls. H1N1-specific T cells were detected in only 2 of 8 evaluable patients compared with 4 of 4 controls. H1N1-specific T cells were functional, capable of producing interferon γ, tumor necrosis factor α, and CD107a mobilization. Furthermore, CD154 was up-regulated on CD4(+) T cells in 3 of 4 controls and 2 of 2 patients who had both B cell and T cell responses to H1N1. Post-H1N1 infection, 5 of 8 patients developed seasonal influenza-specific T cells, suggesting cross-reactivity induced by H1N1 infection. These data offer novel insights into humoral and cell-mediated immunologic responses to primary H1N1 infection.

Regulation of multiple myeloma survival and progression by CD1d.

Down-regulation of conventional human leukocyte antigen (HLA) class I and II molecules from the surface of tumor cells is an important mechanism for tumor immune evasion, survival, and progression. Whether CD1d, a nonconventional, glycolipid-presenting HLA class I-like molecule instructing the function of the immunoregulatory invariant NKT cells can affect tumor cell survival is not known. Here we show that CD1d is highly expressed in premalignant and early myeloma, but with disease progression its expression is reduced and eventually in advanced stages and myeloma cell lines is lost altogether, suggesting that CD1d impacts negatively on myeloma cell survival. Consistent with this, engagement of CD1d by anti-CD1d monoclonal antibodies (mAbs) induces cell death of myeloma cell lines with restored CD1d expression and primary myeloma cells. Cell death induced by monoclonal antibody engagement of CD1d is associated with overexpression of proapoptotic Bax and mitochondrial membrane potential loss but it is caspase-activation independent; in addition, it requires the cytoplasmic tail but not the Tyr residue critical for lysosomal sorting of CD1d. Finally, anti-CD1d cooperates with antimyeloma agents in the killing of myeloma cells. Thus, this work provides evidence linking a novel function of CD1d in the regulation of cell death with tumor survival and progression in humans.

LACE-conditioned autologous stem cell transplantation for relapsed or refractory diffuse large B-cell lymphoma: treatment outcome and risk factor analysis from a single centre.

High-dose chemotherapy followed by autologous stem cell transplantation (ASCT) is a recognized treatment option for patients with relapsed diffuse large B-cell lymphoma. We have analysed 51 patients who underwent ASCT after LACE (lomustine (CCNU), cytarabine (Ara-C), cyclophosphamide, etoposide) conditioning for relapsed (n = 34, 67%) or primary refractory (n = 17, 33%) diffuse large B-cell lymphoma. With a median follow-up of 60 months (range 2-216) the probabilities of overall survival (OS) and progression-free survival (PFS) at 5 years were 47 and 42%, respectively. The cumulative treatment-related mortality was 10% (n = 5). Probabilities for OS and PFS at 5 years were 56 and 50% for patients with chemosensitive and 29 and 27% for patients with chemorefractory disease. In multivariate analysis abnormal pre-ASCT levels of C-reactive protein (>5 mg/L) were identified as a risk factor for worse OS, whereas abnormal pre-ASCT levels of C-reactive protein and chemoresistance predicted inferior PFS. LACE followed by ASCT is an effective treatment for approximately half of patients with chemosensitive relapsed diffuse large B-cell lymphoma, and a proportion of chemorefractory patients also benefit.

Percutaneous vertebroplasty to treat painful myelomatous vertebral deposits-long-term efficacy outcomes.

Developed for benign conditions including osteoporotic fractures and haemangiomas, vertebroplasty has since been employed in neoplastic lesions, including myeloma. Advances in myeloma treatments, yielding improved survival times, have led to an increasing need for effective therapies that improve quality of life. The first randomised trials of vertebroplasty to treat painful osteoporotic crush fractures have cast doubt of its benefit over a placebo procedure, with a proposed rationale that fracture healing over time may account for the non-superiority of the results. However, these findings cannot be extrapolated to myeloma where the pathology is one of progressive bony destruction coupled with failure of new bone formation. In this paper, we present the outcome data for myeloma patients treated at our tertiary referral centre over a 5-year period, focusing on both subjective and objective measures of efficacy and safety. Records were reviewed to extract pain score, function and analgesia pre/post-procedure. Where possible, patients were then contacted directly and asked to assess their benefit by grading change in pain score, analgesia use and mobility. Performance status was assessed using the Eastern Cooperative Oncology Group scale. Of the 26 patients treated for painful thoraco-lumbar lesions, 77% reported improved pain score (P < 0.003). Analgesia reduction, better mobility and improved performance status were also seen. Our data support the consideration of vertebroplasty as a first-line treatment for painful myelomatous vertebral disease. Prospective randomised studies are now required to further define its role.

Centromeric repositioning of coreceptor loci predicts their stable silencing and the CD4/CD8 lineage choice.

The differentiation of CD4(+) CD8(+) double positive (DP) thymocytes requires the irreversible choice between two alternative lineages, distinguished by the mutually exclusive expression of either CD4 or CD8. Differentiating DP cells transiently down-regulate both CD4 and CD8, and this has complicated the debate whether the mechanism of CD4/CD8 lineage choice is instructive, stochastic/selective, or more complex in nature. Using fluorescence in situ hybridization, we show that the stable silencing of coreceptor loci, and ultimately lineage choice, is predicted by the spatial repositioning of coreceptor alleles to centromeric heterochromatin domains. These data provide evidence that lineage-specific developmental programs are established early during the transition from the DP to the single positive stage.

Rational treatment of chemotherapy-induced peripheral neuropathy with capsaicin 8% patch: from pain relief towards disease modification.

PURPOSE: Chemotherapy-induced peripheral neuropathy (CIPN) with associated chronic pain is a common and disabling condition. Current treatments for neuropathic pain in CIPN are largely ineffective, with unfavorable side-effects. The capsaicin 8% patch (capsaicin 179 mg patch) is approved for the treatment of neuropathic pain: a single topical cutaneous application can produce effective pain relief for up to 12 weeks. We assessed the therapeutic potential of capsaicin 8% patch in patients with painful CIPN, and its mechanism of action. PATIENTS AND METHODS: 16 patients with chronic painful CIPN (mean duration 2.5 years), in remission for cancer and not receiving chemotherapy, were treated with 30 min application of capsaicin 8% patch to the feet. Symptoms were monitored using the 11-point numerical pain rating scale (NPRS), and questionnaires. Investigations were performed at baseline and three months after patch application, including skin biopsies with a range of markers, and quantitative sensory testing (QST). RESULTS: Patients reported significant reduction in spontaneous pain (mean NPRS: -1.27; 95% CI 0.2409 to 2.301; p=0.02), touch-evoked pain (-1.823; p=0.03) and cold-evoked pain (-1.456; p=0.03). Short-Form McGill questionnaire showed a reduction in neuropathic (p=0.0007), continuous (p=0.01) and overall pain (p=0.004); Patient Global Impression of Change showed improvement (p=0.001). Baseline skin biopsies showed loss of intra-epidermal nerve fibers (IENF), and also of sub-epidermal nerve fibers quantified by image analysis. Post-patch application skin biopsies showed a significant increase towards normalization of intra-epidermal and sub-epidermal nerve fibers (for IENF: structural marker PGP9.5, p=0.009; heat receptor TRPV1, p=0.027; regenerating nerve marker GAP43, p=0.04). Epidermal levels of Nerve Growth Factor (NGF), Neurotrophin-3 (NT-3), and Langerhans cells were also normalized. QST remained unchanged and there were no systemic side-effects, as in previous studies. CONCLUSION: Capsaicin 8% patch provides significant pain relief in CIPN, and may lead to regeneration and restoration of sensory nerve fibers ie, disease modification.

Impact of route and adequacy of nutritional intake on outcomes of allogeneic haematopoietic cell transplantation for haematologic malignancies.

BACKGROUND: Allogeneic haematopoietic cell transplantation (HCT) is often associated with poor oral intake due to painful mucositis and gastrointestinal sequalae that occur following a preparative regimen of intensive chemotherapy and/or total body radiation. Although attractive to assume that optimal nutrition improves HCT outcomes, there are limited data to support this. It is also unclear whether artificial nutrition support should be provided as enteral tube feeding or parenteral nutrition (PN). METHODS: We analysed day-100 non-relapse mortality (NRM), incidence of acute graft-versus-host disease (GvHD), acute gastrointestinal GvHD, 5-year survival and GvHD-free/relapse-free survival (GRFS) according to both route and adequacy of nutritional intake prior to neutrophil engraftment, together with other known prognostic factors, in a retrospective cohort of 484 patients who underwent allogeneic HCT for haematologic malignancy between 2000 and 2014. RESULTS: Multivariate analyses showed increased NRM with inadequate nutrition (hazard ratio (HR) 4.1; 95% confidence interval (CI) 2.2-7.2) and adequate PN (HR 2.9; 95% CI 1.6-5.4) compared to adequate enteral nutrition (EN) both P < .001. There were increased incidences of gastrointestinal GvHD of any stage and all GvHD ≥ grade 2 in patients who received PN (odds ratio (OR) 2.0; 95% CI 1.2-3.3; P = .006, and OR 1.8; 95% CI 1.1-3.0; P = .018, respectively), compared to adequate EN. Patients who received adequate PN and inadequate nutrition also had reduced probabilities of survival and GRFS at 5 years. CONCLUSION: Adequate EN during the early transplantation course is associated with reduced NRM, improved survival and GRFS at 5 years. Furthermore, adequate EN is associated with lower incidence of overall and gut acute GvHD than PN, perhaps because of its ability to maintain mucosal integrity, modulate the immune response to intensive chemo/radiotherapy and support the gastrointestinal tract environment, including gut microflora.