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.

HOX antisense intergenic RNA (HOTAIR), a long non-coding RNA, plays an important role in the development of many types of cancers. Its function in acute leukemia (AL), however, has not been examined. The present study investigated the role of HOTAIR and its downstream genes in AL, and determined whether it could act as a molecular marker for prediction of leukemia development and prognosis. Real-time quantitative PCR was used to examine the expression of each gene in the HOTAIR signaling pathway in AL patients. The relationship between expression of HOTAIR and downstream genes and AL prognosis was analyzed. Expression of HOTAIR in patients with acute monocytic leukemia (M5) was increased as compared to controls (P<0.05). Compared to patients with low HOTAIR expression, overall survival and event-free survival of patients with high HOTAIR expression was significantly reduced. In addition, the expression of downstream genes in the HOTAIR signaling pathway including EZH2, LSD1, DNMT3A and DNMT3B was significantly increased in AL patients, and showed a significant positive correlation with high expression of HOTAIR (P<0.05). In conclusion, HOTAIR was closely related with a poor prognosis in AL patients. It may be involved in the development of leukemia by mediating methylation of DNA and histones.

Metastasis-associated lung adenocarcinoma transcript 1 (MALAT-1), a long non-coding RNA, has been documented to be a new prognostic marker and gene regulator in several types of cancer, but its potential involvement in acute myeloid leukemia (AML) remains unclear. This study investigated the expression and functional role of MALAT-1 in AML. MALAT-1 expression was assessed by real-time quantitative PCR. After lentiviral-mediated MALAT-1 knockdown, the proliferation of AML cells was determined by CCK-8 and colony formation assays. Cell cycle progression and apoptosis were evaluated by flow cytometry and the expression of caspase-3, −8 and −9 was assessed by western blot analysis. We found that MALAT-1 expression in patients with acute monocytic leukemia (M5) was significantly increased when compared with that of healthy controls, and the overall survival of M5 patients with high MALAT-1 expression was markedly reduced when compared with the overall survival of patients with low MALAT-1 expression. The analysis of cellular experiments showed that MALAT-1 silencing decreased the proliferation of M5 cells (U-937 and THP-1), inhibited cell cycle progression and increased apoptosis. Taken together, these findings suggest that high MALAT-1 expression is closely associated with poor prognosis in M5 patients and may play a role in leukemia cell proliferation and apoptosis, and may serve as a promising theranostic marker.