SUMMARY We investigated the transcriptional and epigenetic repression of miR-29 by Myc, HDAC3, and EZH2 in mantle cell lymphoma and other Myc-associated lymphomas. We demonstrate that miR-29 is repressed by Myc through a co-repressor complex with HDAC3 and EZH2. Myc contributes to EZH2 upregulation via repression of the EZH2 targeting miR-26a, and EZH2 induces Myc via inhibition of the Myc targeting miR-494 to create positive feedback. Combined inhibition of HDAC3 and EZH2 cooperatively disrupted the Myc-EZH2-miR-29 axis, resulting in restoration of miR-29 expression, down-regulation of miR-29 targeted genes, and lymphoma growth suppression in vitro and in vivo. These findings define a Myc-mediated miRNA repression mechanism, shed light on Myc lymphomagenesis mechanisms and reveals promising therapeutic targets for aggressive B-cell malignancies.

Mesenchymal stem cells (MSC) inhibit the response of allogeneic T lymphocytes in culture. Because the mechanisms of this effect may differ according to the existence of cell contact, we investigated the differences in gene expression of inhibitory molecules during MSC-T lymphocyte coculture when cell contact does and does not occur. Human MSC and T lymphocytes were cultured together in standard and transwell cultures. MSC gene expression was analyzed by semiquantitative real-time RT-PCR. MSC elicited a high dose-dependent inhibition of T lymphocytes in cultures with cell contact, but inhibition occurred even without cell contact. In both cases, we observed significant upregulation of IDO, LIF, and HLA-G, along with downregulation of HGF and SDF1. In cultures with cell contact, IL-10 and TGF-β transcripts were expressed in a significantly higher level than in cultures without this contact. Furthermore, in the latter, the increased inhibition of T-cell proliferation was positively correlated with IDO gene expression and negatively correlated with SDF1 gene expression. MSC appear to induce T-cell tolerance by two distinct mechanisms. The first of these, which does not require cell contact, induces expression of the tolerogenic genes IDO, LIF, and HLA-G. The second mechanism, which is contact dependent, modulates IL-10 and TGF-β gene expression. These two mechanisms probably play separate roles in MSC-induced tolerance in allogeneic hematopoietic stem cell transplantation.

The efficacy and safety of chidamide, a new subtype-selective histone deacetylase (HDAC) inhibitor, have been demonstrated in a pivotal phase II clinical trial, and chidamide has been approved by the China Food and Drug Administration (CFDA) as a treatment for relapsed or refractory peripheral T cell lymphoma (PTCL). This study sought to further evaluate the real-world utilization of chidamide in 383 relapsed or refractory PTCL patients from April 2015 to February 2016 in mainland China. For patients receiving chidamide monotherapy (n = 256), the overall response rate (ORR) and disease control rate (DCR) were 39.06 and 64.45%, respectively. The ORR and DCR were 51.18 and 74.02%, respectively, for patients receiving chidamide combined with chemotherapy (n = 127). For patients receiving chidamide monotherapy and chidamide combined with chemotherapy, the median progression-free survival (PFS) was 129 (95% CI 82 to 194) days for the monotherapy group and 152 (95% CI 93 to 201) days for the combined therapy group (P = 0.3266). Most adverse events (AEs) were of grade 1 to 2. AEs of grade 3 or higher that occurred in ≥5% of patients receiving chidamide monotherapy included thrombocytopenia (10.2%) and neutropenia (6.2%). For patients receiving chidamide combined with chemotherapy, grade 3 to 4 AEs that occurred in ≥5% of patients included thrombocytopenia (18.1%), neutropenia (12.6%), anemia (7.1%), and fatigue (5.5%). This large real-world study demonstrates that chidamide has a favorable efficacy and an acceptable safety profile for refractory and relapsed PTCL patients. Chidamide combined with chemotherapy may be a new treatment choice for refractory and relapsed PTCL patients but requires further investigation.Electronic supplementary materialThe online version of this article (doi:10.1186/s13045-017-0439-6) contains supplementary material, which is available to authorized users.

In this study, we utilize a special visual stimulation protocol, called motion reversal, to present a novel steady-state motion visual evoked potential (SSMVEP)-based BCI paradigm that relied on human perception of motions oscillated in two opposite directions. Four Newton's rings with the oscillating expansion and contraction motions served as visual stimulators to elicit subjects' SSMVEPs. And four motion reversal frequencies of 8.1, 9.8, 12.25 and 14 Hz were tested. According to Canonical Correlation Analysis (CCA), the offline accuracy and ITR (mean ± standard deviation) over six healthy subjects were 86.56±9.63% and 15.93±3.83 bits/min, respectively. All subjects except one exceeded the level of 80% mean accuracy. Circular Hotelling's T-Squared test () also demonstrated that most subjects exhibited significantly strong stimulus-locked SSMVEP responses. The results of declining exponential fittings exhibited low-adaptation characteristics over the 100-s stimulation sequences in most experimental conditions. Taken together, these results suggest that the proposed paradigm can provide comparable performance with low-adaptation characteristic and less visual discomfort for BCI applications.

A dynamic interaction occurs between the lymphoma cell and its microenvironment, with each profoundly influencing the behavior of the other. Here, using a clonogenic coculture growth system and a xenograft mouse model, we demonstrated that adhesion of mantle cell lymphoma (MCL) and other non-Hodgkin lymphoma cells to lymphoma stromal cells confers drug resistance, clonogenicity, and induction of histone deacetylase 6 (HDAC6). Furthermore, stroma triggered a c-Myc/miR-548m feed-forward loop, linking sustained c-Myc activation, miR-548m downregulation, and subsequent HDAC6 upregulation and stroma-mediated cell survival and lymphoma progression in lymphoma cell lines, primary MCL and other B cell lymphoma cell lines. Treatment with an HDAC6-selective inhibitor alone or in synergy with a c-Myc inhibitor enhanced cell death, abolished cell adhesion-mediated drug resistance, and suppressed clonogenicity and lymphoma growth ex vivo and in vivo. Together, these data suggest that the lymphoma-stroma interaction in the lymphoma microenvironment directly impacts the biology of lymphoma through genetic and epigenetic regulation, with HDAC6 and c-Myc as potential therapeutic targets.