miR-17-92 cluster-BTG2 axis regulates B-cell receptor signaling in mantle cell lymphoma.

B-cell receptor (BCR) signaling is critically activated and stable for mantle cell lymphoma (MCL), but the underlying mechanism of the activated BCR signaling pathway is not clear. The pathogenic basis of miR-17-92 cluster remains unclear although the oncogenic microRNA (miRNA) miR-17-92 cluster is highly expressed in patients with MCL. We revealed that miR-17-92 cluster overexpression is partly dependent on SOX11 expression and chromatin acetylation of MIR17HG enhancer regions. Moreover, miR-17-92 cluster regulates not only cell proliferation but BCR signaling activation in MCL cell lines. To comprehensively identify miR-17-92 cluster target genes, we performed pulldown-seq, where target RNA of miRNA was captured using the biotinylated miRNA mimics and magnetic bead-coated streptavidin, and quantified using next-generation sequencing. The pulldown-seq identified novel miRNA target genes, including tumor suppressors such as BTG2 (miR-19b), CDKN2A (miR-17), SYNE1 (miR-20a), TET2 (miR-18, miR-19b, and miR-92a), TNFRSF10A (miR-92a), and TRAF3 (miR-17). Notably, the gene expression profile data of patients with MCL revealed that BTG2 expression was negatively associated with that of BCR signature genes, and low BTG2 expression was associated with poor overall survival. Moreover, BTG2 silencing in MCL cell lines significantly induced BCR signaling overactivation and cell proliferation. Our results suggest an oncogenic role of miR-17-92 cluster-activating BCR signaling throughout BTG2 deregulation in MCL. Furthermore, this may contribute to the prediction of the therapeutic efficacy and improved outcomes of MCL.

Two novel high-risk adult B-cell acute lymphoblastic leukemia subtypes with high expression of CDX2 and IDH1/2 mutations.

The genetic basis of leukemogenesis in adults with B-cell acute lymphoblastic leukemia (B-ALL) is largely unclear, and its clinical outcome remains unsatisfactory. This study aimed to advance the understanding of biological characteristics, improve disease stratification, and identify molecular targets of adult B-ALL. Adolescents and young adults (AYA) (15 to 39 years old, n = 193) and adults (40 to 64 years old, n = 161) with Philadelphia chromosome-negative (Ph-) B-ALL were included in this study. Integrated transcriptomic and genetic analyses were used to classify the cohort into defined subtypes. Of the 323 cases included in the RNA sequencing analysis, 278 (86.1%) were classified into 18 subtypes. The ZNF384 subtype (22.6%) was the most prevalent, with 2 novel subtypes (CDX2-high and IDH1/2-mut) identified among cases not assigned to the established subtypes. The CDX2-high subtype (3.4%) was characterized by high expression of CDX2 and recurrent gain of chromosome 1q. The IDH1/2-mut subtype (1.9%) was defined by IDH1 R132C or IDH2 R140Q mutations with specific transcriptional and high-methylation profiles. Both subtypes showed poor prognosis and were considered inferior prognostic factors independent of clinical parameters. Comparison with a previously reported pediatric B-ALL cohort (n = 1003) showed that the frequencies of these subtypes were significantly higher in AYA/adults than in children. We delineated the genetic and transcriptomic landscape of adult B-ALL and identified 2 novel subtypes that predict poor disease outcomes. Our findings highlight the age-dependent distribution of subtypes, which partially accounts for the prognostic differences between adult and pediatric B-ALL.

Triple targeting of RSK, AKT, and S6K as pivotal downstream effectors of PDPK1 by TAS0612 in B-cell lymphomas.

B-cell lymphomas (BCLs) are the most common disease entity among hematological malignancies and have various genetically and molecularly distinct subtypes. In this study, we revealed that the blockade of phosphoinositide-dependent kinase-1 (PDPK1), the master kinase of AGC kinases, induces a growth inhibition via cell cycle arrest and the induction of apoptosis in all eight BCL-derived cell lines examined, including those from activated B-cell-like diffuse large B-cell lymphoma (DLBCL), double expressor DLBCL, Burkitt lymphoma, and follicular lymphoma. We also demonstrated that, in these cell lines, RSK2, AKT, and S6K, but not PLK1, SGK, or PKC, are the major downstream therapeutic target molecules of PDPK1 and that RSK2 plays a central role and AKT and S6K play subsidiary functional roles as the downstream effectors of PDPK1 in cell survival and proliferation. Following these results, we confirmed the antilymphoma efficacy of TAS0612, a triple inhibitor for total RSK, including RSK2, AKT, and S6K, not only in these cell lines, regardless of disease subtypes, but also in all 25 patient-derived B lymphoma cells of various disease subtypes. At the molecular level, TAS0612 caused significant downregulation of MYC and mTOR target genes while inducing the tumor suppressor TP53INP1 protein in these cell lines. These results prove that the simultaneous blockade of RSK2, AKT, and S6K, which are the pivotal downstream substrates of PDPK1, is a novel therapeutic target for the various disease subtypes of BCLs and line up TAS0612 as an attractive candidate agent for BCLs for future clinical development.

Long-term follow-up after R-High CHOP/CHASER/LEED with Auto-PBSCT in untreated mantle cell lymphoma-Final analysis of JCOG0406.

Progression-free survival after R-High CHOP/CHASER/LEED with auto-PBSCT in untreated mantle cell lymphoma in JCOG0406 study. A continuous pattern of relapse was observed.

The Rationale for the Dual-Targeting Therapy for RSK2 and AKT in Multiple Myeloma.

Multiple myeloma (MM) is characterized by remarkable cytogenetic/molecular heterogeneity among patients and intraclonal diversity even in a single patient. We previously demonstrated that PDPK1, the master kinase of series of AGC kinases, is universally active in MM, and plays pivotal roles in cell proliferation and cell survival of myeloma cells regardless of the profiles of cytogenetic and genetic abnormalities. This study investigated the therapeutic efficacy and mechanism of action of dual blockade of two major PDPK1 substrates, RSK2 and AKT, in MM. The combinatory treatment of BI-D1870, an inhibitor for N-terminal kinase domain (NTKD) of RSK2, and ipatasertib, an inhibitor for AKT, showed the additive to synergistic anti-tumor effect on human MM-derived cell lines (HMCLs) with active RSK2-NTKD and AKT, by enhancing apoptotic induction with BIM and BID activation. Moreover, the dual blockade of RSK2 and AKT exerted robust molecular effects on critical gene sets associated with myeloma pathophysiologies, such as those with MYC, mTOR, STK33, ribosomal biogenesis, or cell-extrinsic stimuli of soluble factors, in HMCLs. These results provide the biological and molecular rationales for the dual-targeting strategy for RSK2 and AKT, which may overcome the therapeutic difficulty due to cytogenetic/molecular heterogeneity in MM.

Lenalidomide and pomalidomide potently interfere with induction of myeloid-derived suppressor cells in multiple myeloma.

An increase in immunosuppressive myeloid-derived suppressor cells (MDSCs) is associated with disease progression and treatment resistance in multiple myeloma (MM). We investigated the mechanisms underlying MDSC induction, and sought to discover a strategy for prevention of MDSC induction in MM. Using a transwell co-culture system, four of nine examined human myeloma-derived cell lines (HMCLs) were potent in inducing monocytic (M)-MDSCs from normal peripheral blood mononuclear cells (PBMCs). As the results, we identified that secretion of C-C motif chemokine ligand 5 (CCL5) and macrophage migration inhibitory factor (MIF) by myeloma cells is a prerequisite for induction of MDSCs in MM. The immunomodulatory drug (IMiD) compounds, such as lenalidomide (LEN) and pomalidomide (POM), were identified as potent inhibitors of MDSC induction through bidirectional molecular effects of cereblon (CRBN)-dependent and -independent downregulation of CCL5 and MIF in myeloma cells; and downregulation of C-C motif chemokine receptor 5, a receptor for CCL5, and induction of interferon regulatory factor 8, a critical transcription factor for monocytic differentiation, in PBMCs. In the present study of the molecular mechanisms underlying MDSC induction, we identified a novel effect of LEN and POM of inhibiting MDSC induction via overlapping regulatory effects in myeloma cells and normal PBMCs.

Sequential therapy of four cycles of bortezomib, melphalan, and prednisolone followed by continuous lenalidomide and dexamethasone for transplant-ineligible newly diagnosed multiple myeloma.

The combinations of melphalan, bortezomib, and prednisolone (VMP) and of lenalidomide and dexamethasone (Rd) are standard treatment strategies for transplant-ineligible newly diagnosed multiple myeloma (NDMM). To make the most of these two strategies, we investigated the efficacy and feasibility of first-line treatment with 4 cycles of VMP followed by continuous Rd therapy in a multi-institutional phase 2 study in Japanese patients with transplant-ineligible NDMM. Thirty-six patients of median age 74 years old with NDMM initially received 35-day cycles of VMP: oral melphalan (6 mg/m2) and prednisolone (60 mg/m2) on days 1 to 4 and bortezomib (1.3 mg/m2) on days 1, 8, 15, and 22. After 4 cycles of VMP, treatment was switched to 28-day cycles of Rd, which was continued until disease progression or emergence of an unacceptable adverse event (AE) in 33 patients, while one patient who achieved CR after VMP continued VMP at the physician's discretion. The overall response rates after VMP and after Rd were 66.7% and 86.1%, including CR rates of 5.6% and 36.1%, respectively. In a median follow-up period of 34.3 months, the progression-free survival and overall survival rates at 3 years were 43.2% and 81.3%, respectively. Grade 3-4 hematological AEs included neutropenia (39% with VMP and 24% with Rd) and thrombocytopenia (11% with VMP and 3% with Rd). There was no death due to an AE. In conclusion, sequential therapy with VMP followed by Rd is effective and mostly feasible for transplant-ineligible NDMM. The study is registered as UMIN000034815.

Carfilzomib monotherapy in Japanese patients with relapsed or refractory multiple myeloma: A phase 1/2 study.

This multicenter, open-label phase 1/2 study evaluated single-agent carfilzomib in 50 heavily pretreated Japanese patients with relapsed/refractory multiple myeloma (median of five prior treatments). In phase 1, patients were dosed at three levels: 15, 20, or 20/27 mg/m2 . Maximum tolerated dosage was not reached at the tolerability evaluation. Patients in phase 2 were treated with 20/27 mg/m2 carfilzomib. Median duration of exposure to carfilzomib in the 20/27 mg/m2 group at this final analysis was 4.7 months (range: 0.3-39.4). Overall response rate in the 20/27 mg/m2 group, primary endpoint of the study, was 22.5% (n = 9) (95% confidence interval, 12.3-37.5) with 2.5% (n = 1) stringent complete response. Median progression-free survival and overall survival in the 20/27 mg/m2 group were 5.1 months (95% CI, 2.8-13.6) and 22.9 months (95% CI, 14.1-not estimable), respectively. Frequently occurring grade ≥3 adverse events in the 20/27 mg/m2 group included lymphopenia (72.5%), neutropenia (40.0%), and leukopenia (32.5%). Giving long-term carfilzomib monotherapy led to long-term overall survival for heavily pretreated multiple myeloma patients with a favorable safety profile. Carfilzomib monotherapy can be a good option for heavily pretreated multiple myeloma patients.

Dual targeting of bromodomain-containing 4 by AZD5153 and BCL2 by AZD4320 against B-cell lymphomas concomitantly overexpressing c-MYC and BCL2.

Despite the recent therapeutic progress, the prognoses of diffuse large B-cell lymphomas (DLBCLs) that concomitantly overexpress c-MYC and BCL2, i.e., double hit lymphoma (DHL) and double expressing lymphoma (DEL), remain poor. This study examined triple targeting of c-MYC, BCL2 and the B-cell receptor (BCR) signaling pathway for DHL and DEL. We first used AZD5153, a novel bivalent inhibitor for bromodomain-containing 4 (BRD4), in DHL- and DEL-derived cell lines, because BRD4 regulates disease type-oriented key molecules for oncogenesis. AZD5153 was more effective than conventional monovalent BRD4 inhibitors, JQ1 and I-BET151, in inhibiting cell proliferation of a DHL-derived cell line and two DEL-derived cell lines, with at least 10-fold lower half growth inhibitory concentrations. AZD5153 caused G1/S cell cycle blockade, while the apoptosis-inducing effect was relatively modest. At the molecular level, AZD5153 was potent in downregulating various molecules for oncogenesis, such as c-MYC, AKT2 and MAP3K; those involved in the BCR signaling pathway, such as CD19, BLNK and CD79B; and those associated with B-cell development, such as IKZF1, IKZF3, PAX5, POU2AF1 and EBF1. In contrast, AZD5153 did not decrease anti-apoptotic BCL2 proteins, and did not activate pro-apoptotic BH3-only proteins, except BAD. To augment cell death induction, we added a novel BH3-mimicking BCL2 inhibitor AZD4320 to AZD5153, and found that these two agents had a mostly synergistic antitumor effect by increasing cells undergoing apoptosis in all three cell lines. These results provide a rationale for dual targeting of BRD4 and BCL2 using AZD5153 and AZD4320 as a therapeutic strategy against DHL and DEL.

Multicenter phase 1/2 study of forodesine in patients with relapsed peripheral T cell lymphoma.

Peripheral T cell lymphomas are an aggressive group of non-Hodgkin lymphomas with poor outcomes for most subtypes and no accepted standard of care for relapsed patients. This study evaluated the efficacy and safety of forodesine, a novel purine nucleoside phosphorylase inhibitor, in patients with relapsed peripheral T cell lymphomas. Patients with histologically confirmed disease, progression after ≥ 1 prior treatment, and an objective response to last treatment received oral forodesine 300 mg twice-daily. The primary endpoint was objective response rate (ORR). Secondary endpoints included duration of response, progression-free survival (PFS), overall survival (OS), and safety. Forty-eight patients (median age, 69.5 years; median of 2 prior treatments) received forodesine. In phase 1 (n = 3 evaluable), no dose-limiting toxicity was observed during the first 28 days of forodesine treatment. In phase 2 (n = 41 evaluable), the ORR for the primary and final analyses was 22% (90% CI 12-35%) and 25% (90% CI 14-38%), respectively, including four complete responses (10%). Median PFS and OS were 1.9 and 15.6 months, respectively. The most common grade 3/4 adverse events were lymphopenia (96%), leukopenia (42%), and neutropenia (35%). Dose reduction and discontinuation due to adverse events were uncommon. Secondary B cell lymphoma developed in five patients, of whom four were positive for Epstein-Barr virus. In conclusion, forodesine has single-agent activity within the range of approved therapies in relapsed peripheral T cell lymphomas, with a manageable safety profile, and may represent a viable treatment option for this difficult-to-treat population.

Weekly carfilzomib and dexamethasone in Japanese patients with relapsed or refractory multiple myeloma: A phase 1 and PK/PD trial.

This open-label multicenter phase 1 study evaluated the safety, tolerability, efficacy, pharmacokinetics and pharmacodynamics of weekly carfilzomib and dexamethasone (Cd) in Japanese patients with relapsed or refractory multiple myeloma (RRMM). Carfilzomib was administered by 30-minute intravenous infusion on Days 1, 8 and 15 in a 28-day cycle starting at 20 mg/m2 on Day 1/Cycle 1 and 70 mg/m2 thereafter until progressive disease or unacceptable toxicity. Dexamethasone 40 mg was administered on Days 1, 8, 15 and 22 in Cycles 1-9 and on Days 1, 8 and 15 thereafter. Six patients were enrolled between March 2015 and June 2015. Patients had received a median of 4.5 (range, 4-8) prior regimens; all patients had previous therapies with bortezomib and immunomodulatory drugs. Of the 6 patients, 1 had a dose-limiting toxicity (DLT), and tolerability was confirmed. The DLT was grade 3 thrombotic microangiopathy, which was considered serious and occurred on Day 11/Cycle 1. All 6 patients (100%) experienced at least 1 grade ≥3 adverse event (AE). Two patients (33.3%) experienced AE (also considered adverse drug reactions) leading to study discontinuation: thrombotic microangiopathy (Day 11/Cycle 1) and thrombotic thrombocytopenic purpura (Day 6/Cycle 2). The overall response rate was 83.3% (95% confidence interval, 43.6-97.0). The weekly Cd regimen at a carfilzomib dose of 20/70 mg/m2 was well-tolerated among Japanese patients with RRMM. Our results could be the basis for the further development of carfilzomib treatment considering safety profiles including microangiopathy-related events and efficacy.

R-High-CHOP/CHASER/LEED with autologous stem cell transplantation in newly diagnosed mantle cell lymphoma: JCOG0406 STUDY.

Although induction immunochemotherapy including high-dose cytarabine and rituximab followed by high-dose chemotherapy (HDC) with autologous stem cell transplantation (ASCT) is recommended for younger patients (≤65 years old) with untreated mantle cell lymphoma (MCL), no standard induction and HDC regimen has been established. We conducted a phase II study of induction immunochemotherapy of R-High-CHOP/CHASER followed by HDC of LEED with ASCT in younger patients with untreated advanced MCL. Eligibility criteria included untreated MCL, stage II bulky to IV, and age 20-65 years. Patients received 1 cycle of R-High-CHOP followed by 3 cycles of CHASER every 3 weeks. Peripheral blood stem cells (PBSC) were harvested during CHASER. LEED with ASCT was delivered to patients who responded to R-High-CHOP/CHASER. Primary endpoint was 2-year progression-free survival (PFS). From June 2008 to June 2012, 45 patients (median age 59 years; range 38-65 years) were enrolled. PBSC were successfully harvested from 36 of 43 patients. Thirty-five patients completed ASCT. Two-year PFS was 77% (80% CI 68-84), which met the primary endpoint. Five-year PFS and overall survival were 52% (95% CI 34-68%) and 71% (95% CI 51-84%), respectively. Overall response and complete response rates after induction immunochemotherapy were 96% and 82%, respectively. The most common grade 4 toxicities were hematological. In younger patients with untreated MCL, R-High-CHOP/CHASER/LEED with ASCT showed high efficacy and acceptable toxicity, and it can now be considered a standard treatment option.

Elotuzumab Therapy for Relapsed or Refractory Multiple Myeloma.

BACKGROUND: Elotuzumab, an immunostimulatory monoclonal antibody targeting signaling lymphocytic activation molecule F7 (SLAMF7), showed activity in combination with lenalidomide and dexamethasone in a phase 1b-2 study in patients with relapsed or refractory multiple myeloma. METHODS: In this phase 3 study, we randomly assigned patients to receive either elotuzumab plus lenalidomide and dexamethasone (elotuzumab group) or lenalidomide and dexamethasone alone (control group). Coprimary end points were progression-free survival and the overall response rate. Final results for the coprimary end points are reported on the basis of a planned interim analysis of progression-free survival. RESULTS: Overall, 321 patients were assigned to the elotuzumab group and 325 to the control group. After a median follow-up of 24.5 months, the rate of progression-free survival at 1 year in the elotuzumab group was 68%, as compared with 57% in the control group; at 2 years, the rates were 41% and 27%, respectively. Median progression-free survival in the elotuzumab group was 19.4 months, versus 14.9 months in the control group (hazard ratio for progression or death in the elotuzumab group, 0.70; 95% confidence interval, 0.57 to 0.85; P<0.001). The overall response rate in the elotuzumab group was 79%, versus 66% in the control group (P<0.001). Common grade 3 or 4 adverse events in the two groups were lymphocytopenia, neutropenia, fatigue, and pneumonia. Infusion reactions occurred in 33 patients (10%) in the elotuzumab group and were grade 1 or 2 in 29 patients. CONCLUSIONS: Patients with relapsed or refractory multiple myeloma who received a combination of elotuzumab, lenalidomide, and dexamethasone had a significant relative reduction of 30% in the risk of disease progression or death. (Funded by Bristol-Myers Squibb and AbbVie Biotherapeutics; ELOQUENT-2 ClinicalTrials.gov number, NCT01239797.).

Correction to: Multicenter phase 1/2 study of forodesine in patients with relapsed peripheral T cell lymphoma.

The original version of this article contained a mistake in Fig. 4. The horizontal axis should be 36 instead of 60.

An adult-onset case of chronic active Epstein-Barr virus infection with fulminant clinical course.

A 56-year-old Japanese male with chronic active Epstein-Barr virus (EBV) infection (CAEBV) who developed systemic gamma-delta T-cell lymphoproliferative disease (LPD) is reported. Although immune cooling therapy was effective, he died of sudden and severe hypoxia and anemia soon after the initiation of cytotoxic chemotherapy that had been previously recommended. There might remain a difficulty to control fulminant adult-onset CAEBV. Additionally, we describe three types of lymphoid cells that were observed in his peripheral blood: morphologically normal lymphocytes, large blastic cells and mature ones with rough granules. Morphological observation appeared to be useful to estimate clinical manifestations. Since CAEBV is extremely rare disease in adult population, it is important to accumulate clinical data to more understand the pathogenesis or to establish treatment strategy.

Persistent detection of alternatively spliced BCR-ABL variant results in a failure to achieve deep molecular response.

Treatment with tyrosine kinase inhibitors (TKI) may sequentially induce TKI-resistant BCR-ABL mutants in chronic myeloid leukemia (CML). Conventional PCR monitoring of BCR-ABL is an important indicator to determine therapeutic intervention for preventing disease progression. However, PCR cannot separately quantify amounts of BCR-ABL and its mutants, including alternatively spliced BCR-ABL with an insertion of 35 intronic nucleotides (BCR-ABLIns35bp ) between ABL exons 8 and 9, which introduces the premature termination and loss of kinase activity. To assess the clinical impact of BCR-ABL mutants, we performed deep sequencing analysis of BCR-ABL transcripts of 409 samples from 37 patients with suboptimal response to frontline imatinib who were switched to nilotinib. At baseline, TKI-resistant mutations were documented in 3 patients, whereas BCR-ABLIns35bp was detected in all patients. After switching to nilotinib, both BCR-ABL and BCR-ABLIns35bp became undetectable in 3 patients who attained complete molecular response (CMR), whereas in the remaining all 34 patients, BCR-ABLIns35bp was persistently detected, and minimal residual disease (MRD) fluctuated at low but detectable levels. PCR monitoring underestimated molecular response in 5 patients whose BCR-ABLIns35bp was persisted, although BCR-ABLIns35bp does not definitively mark TKI resistance. Therefore, quantification of BCR-ABLIns35bp is useful for evaluating "functional" MRD and determining the effectiveness of TKI with accuracy.

Multicenter phase II study of nivolumab in Japanese patients with relapsed or refractory classical Hodgkin lymphoma.

Overexpression of programmed death-1 (PD-1) ligands contributes to an immunosuppressive microenvironment. Nivolumab is a PD-1-blocking antibody that inhibits the PD-1 pathway and showed good efficacy in several types of malignancy. This phase II study examined the efficacy and safety of nivolumab in 17 Japanese patients with refractory/relapsed classical Hodgkin lymphoma previously treated with brentuximab vedotin. Sixteen patients were included in efficacy analyses and 17 in safety analyses. The primary endpoint was the centrally assessed objective response rate (ORR). The study was commenced in March 2015. We report data obtained at a cutoff of 16 March 2016, at which time 11 patients were still receiving nivolumab. The median (range) duration of treatment and follow-up were 7.0 (1.4-10.6) months and 9.8 (6.0-11.1) months, respectively. All 17 patients had previously received brentuximab vedotin. The ORR was 81.3% (95% confidence interval [CI]: 54.4-96.0%; 13/16 patients), with complete remission and partial remission in 4 and 9 patients, respectively. The overall survival (OS) and progression-free survival (PFS) rates at 6 months were 100 and 60.0% (95% CI: 31.8-79.7%), respectively; the median OS and PFS were not reached. The most common adverse events (AE) were pyrexia (41.2%), pruritus (35.3%), rash (35.3%) and hypothyroidism (29.4%). Four patients (23.5%) experienced grade 3 or 4 AE, but most AE were of grade 1 or 2. In conclusion, nivolumab is a potentially effective and tolerable treatment option for Japanese patients with relapsed/refractory classical Hodgkin lymphoma previously treated with brentuximab vedotin.

Epigenetic repression of miR-375 is the dominant mechanism for constitutive activation of the PDPK1/RPS6KA3 signalling axis in multiple myeloma.

Cytogenetic/molecular heterogeneity is the hallmark of multiple myeloma (MM). However, we recently showed that the serine/threonine kinase PDPK1 and its substrate RPS6KA3 (also termed RSK2) are universally active in MM, and play pivotal roles in myeloma pathophysiology. In this study, we assessed involvement of aberrant miR-375 repression in PDPK1 overexpression in MM. An analysis of plasma cells from 30 pre-malignant monoclonal gammopathies of undetermined significance and 73 MM patients showed a significant decrease in miR-375 expression in patient-derived plasma cells regardless of the clinical stage, compared to normal plasma cells. Introduction of miR-375 reduced PDPK1 expression in human myeloma cell lines (HMCLs), indicating that miR-375 is the dominant regulator of PDPK1 expression. In addition, miR-375 introduction also downregulated IGF1R and JAK2 in HMCLs. CpG islands in the MIR375 promoter were pathologically hypermethylated in all 8 HMCLs examined and in most of 58 patient-derived myeloma cells. Treatment with SGI-110, a hypomethylating agent, and/or trichostatin A, a histone deacetylase inhibitor, increased miR-375 expression, but repressed PDPK1, IGF1R and JAK2 in HMCLs. Collectively, these results show the universal involvement of overlapping epigenetic dysregulation for abnormal miR-375 repression in MM, which is likely to contribute to myelomagenesis and to subsequent myeloma progression by activating oncogenic signalling pathways.

Clinicopathological analysis of 46 cases with CD4+ and/or CD56+ immature haematolymphoid malignancy: reappraisal of blastic plasmacytoid dendritic cell and related neoplasms.

AIMS: In this study, we aimed to investigate the clinicopathological features of CD4+ and/or CD56+ immature haematolymphoid malignancy (iHLM), including blastic plasmacytoid dendritic cell neoplasm (BPDCN). METHODS AND RESULTS: We analysed the clinicopathological features of 46 patients diagnosed consecutively with CD4+ /CD56+ iHLM. These cases were categorised into three groups based on their immunohistochemical expression of three plasmacytoid dendritic cell (pDC) markers [CD123, CD303 and T cell leukaemia/lymphoma (TCL1)]: cutaneous BPDCN (n = 35), non-cutaneous BPDCN (n = 6) and non-BPDCN-type CD56+ neoplasms (n = 5). Compared to non-cutaneous BPDCN, cutaneous BPDCN was associated with an older median age at onset (72 years versus 45 years, P < 0.05), and higher positivity for CD4 (P < 0.05), CD123 (P < 0.05) and 2-3 pDC markers (89% versus 50%, P = 0.05). Cutaneous BPDCN was divided into terminal deoxynucleotidyl transferase (TdT)+ and TdT- subgroups, which did not differ in prognosis, although TdT+ cases showed a lower median onset age (66 years versus 79 years, P < 0.05) and higher frequency of extracutaneous lesions (P < 0.05). Compared to the BPDCN groups, non-BPDCN-type CD56+ neoplasm cases showed higher cytoplasmic CD3 positivity (P < 0.05) and less frequent BCL-2 expression (P < 0.05), and lacked cutaneous lesions. However, the survival curves overlapped. Notably, one case involved an unusual composite neoplasm, comprising CD56+ lymphoblastic lymphoma and mature CD56+ cytotoxic T cell lymphoma. CONCLUSIONS: Our present data support the recognition of cutaneous BPDCN as a homogenous entity, in contrast to the non-cutaneous form. Additional research is warranted to characterise non-BPDCN-type CD56+ neoplasms.

Predicting risk factors for varicella zoster virus infection and postherpetic neuralgia after hematopoietic cell transplantation using ordered logistic regression analysis.

To identify risk factors for varicella zoster virus (VZV) infection and postherpetic neuralgia (PHN) after hematopoietic cell transplantation (HCT), we conducted a retrospective chart review of 163 consecutive patients who underwent HCT between November 2004 and July 2014. Overall, the male/female (M/F) ratio was 80/83, median age at HCT was 54 (range 15-69) years, and autologous/allogeneic HCT (auto/allo-HCT) ratio was 71/92. Forty-four patients [M/F, 25/19; median age, 57 (range: 16-68) years; auto/allo-HCT, 26/18] developed VZV infection after HCT. All cases were successfully treated with acyclovir (ACV) or valacyclovir, and there was no VZV-related death. Nine (20%) of the 44 patients [M/F, 5/4; median age, 58 (range: 21-63) years; auto/allo-HCT, 7/2] developed PHN after resolution of zoster. Multivariate ordered logistic analysis identified receiving immunosuppressive therapy at the cessation of ACV [odds ratio (OR) = 74.53; 95% confidence interval (CI) = 6.99-794.32; P = 0.0004] as a risk factor for VZV infection and PHN in allo-HCT recipients. However, in auto-HCT recipients, only advanced age was identified as a risk factor (OR = 1.06, 95% CI = 1.002-1.127, P = 0.0429). Our findings indicate receiving immunosuppressive therapy at the cessation of ACV is a significant risk factor for allo-HCT recipients, while advanced age is a significant risk factor for auto-HCT recipients.