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Objective: Epstein–Barr virus-positive diffuse large B-cell lymphoma is a provisional entity in the 2008 World Health Organization classification of tumors of hematopoietic and lymphoid tissues. Reports on the characteristics and clinical outcome of this disease in different geographic regions showed great disparities. Methods: To define the clinical characteristics as well as the prognostic impact of Epstein – Barr virus infection on diffuse large B-cell lymphoma in Taiwan, we retrospectively investigated the Epstein–B arr virus status of 89 patients with newly diagnosed diffuse large B-cell lymphoma in our institute. Results: Using a cutoff point of positive nuclear staining of Epstein–Barr virus-encoded RNA1-in situ hybridization in � 20% of the examined cells, we identified 15 cases (16.9%) of the entire study cohort as Epstein–B arr virus-positive diffuse large B-cell lymphoma. The clinical and laboratory features were not different between Epstein– Barr virus-positive and -negative diffuse large B-cell lymphoma patients. Univariate analysis showed patients with diffuse large B-cell lymphoma that were either Epstein–B arr virus-positive or had activated B-cell-like features had an inferior overall survival. Older age, advanced stage and lymphoma with activated B-cell-like features or Epstein–Barr virus-encoded RNA positivity were independent prognostic factors affecting overall survival on multivariate analysis. Patients with two or three of these adverse-risk factors were considered high risk and fared far worse than patients with no or only one adverse factor. Conclusions: Taken together, we demonstrated that a higher frequency of Epstein–Barr virus association was detected in a Taiwanese cohort of diffuse large B-cell lymphoma patients, and Epstein –B arr virus-encoded RNA positivity was shown to add important prognostic value in these patients.

Triple-negative breast cancer (TNBC) is a highly aggressive form of breast cancer often associated with poor prognosis. Owing to the lack of therapeutic targets, patients with TNBC tend to rely on standard chemotherapy; however, chemo-resistance often develops in TNBC as a result of deregulated cell death control like in many other tumors. Long non-coding RNAs (lncRNAs) are transcripts longer than 200bp and have little or no protein-coding capacity. Although once considered as transcriptional noise, significant numbers of lncRNAs are now known as modulators of protein expression and functions and are implicated in a range of developmental processes and diseases. As many of them influence oncogenes and tumor suppressors in cancer, they represent excellent biomarkers as well as potential targets for therapy. In order to gain more insight on cell death regulation and to seek potential targets for TNBC, we employed an RNAi screen targeting 2231 lncRNAs in MDA-MB-231 TNBC cells. By using changes in cell metabolic activity (MTT assay) as readouts for primary screen and changes in cell number as confirmation, our unbiased screen identified two novel lncRNAs that drastically reduced cell proliferation when depleted. In addition to cell growth, the two lncRNAs also contribute to cancer cell migration and invasion. Interestingly, our gene profiling analyses and RNA immunoprecipitation studies show the two lncRNAs are involved in signaling cascades known to promote mammary tumorigenesis including EGF and β-catenin. We are now trying to delineate the detailed molecular mechanism(s) by which the two lncRNAs contribute to TNBC tumorigenesis. Together, our current results suggest a possibility for the two novel lncRNAs as drug targets in triple-negative breast cancer. Citation Format: Tse-Chun Kuo, Sheng-Chieh Hsu, Hui-Ju Chou, Pei-Shan Li, Szu-Huei Wu, Yen-Ling Yu, Jen-Shin Song, Hsing-Jien Kung. RNAi screen identified novel long non-coding RNAs involved in cell growth control, migration, and invasion [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3502. doi:10.1158/1538-7445.AM2017-3502

Calreticulin (CALR) mutations were recently identified in patients with essential thrombocythemia (ET) and primary myelofibrosis (PMF) devoid of JAK2 and MPL mutations. We evaluated the clinical, laboratory, and molecular features of a Taiwanese population of patients with ET. Among 147 ET patients, CALR mutations were detected in 33 (22.5 %), JAK2V617F in 94 (63.9 %), and MPL mutations in 4 (2.7 %). Sixteen (10.9 %) patients were negative for all three mutations (CALR, JAK2V617F, and MPL; triple negative). Interestingly, one patient with the type 2 CALR mutation also harbored a low allele burden (0.025 %) of JAK2V617F mutation. Furthermore, we found a novel CALR mutation, with the resultant protein sharing an identical amino acid sequence to the type 6 CALR mutant. Compared to those with JAK2 mutation, CALR-mutated ET patients were characterized by younger age, lower leukocyte count, higher platelet count, and decreased risk of thrombosis. CALR mutations had a favorable impact on thrombosis-free survival (TFS) for ET patients, whereas the respective TFS outcomes were similarly poorer in JAK2-mutated ET and PV patients. Multivariate analysis confirmed that younger age (

Dear Editor,Approximately45%ofacutemyeloidleukemia(AML)shownormal karyotype (cytogenetically normal AML (CN-AML))at diagnosis, which are cytogenetically categorized as inter-mediate risk but is clinically heterogenous. The evaluation ofmolecular mutations offers better prognostication for CN-AML patients. Here, we present a case of molecularly good-risk CN-AML who unusually manifested central nervoussystem disease at the time of first remission.A 51-year-old lady was diagnosed with CN-AML (M2)with favorable-risk molecular profile: mutant NPM1,wild-typeMLL-PTD,andnegativeFLT3-ITD.Shereceivedinduc-tionchemotherapywithdaunorubicin(90mg/m

Epithelial-mesenchymal transition (EMT) is a critical process for inducing stem-like properties of epithelial cancer cells. However, the role of EMT inducers in hematologic malignancies is unknown. Twist1, an EMT inducer necessary for cell migration, has recently been found to have transcriptionally regulatory activity on the expression of Bmi1, and these two are capable of promoting tumorigenesis in a synergized manner. Knowing that Bmi1 expression is essential for maintenance of leukemic stem cells, we speculate that Twist1 might govern the pathogenesis of acute myeloid leukemia (AML) development as well. We used AML cell lines KG1a and THP1 cells, which had low and high expression levels of Twist1, respectively to demonstrate that upregulated Twist1 increased Bmi1 expression in AML. Bmi1 overexpression endued leukemic cells a higher proliferative potential and increased resistance to apoptosis. In primary AML samples, there was strong positive correlation between the expression levels of Twist1 and Bmi1. AML Patients whose leukemic blasts harbored overexpressed Twist1 had a more aggressive clinical phenotype, but they were more likely to have a better clinical outcome after standard therapy. In vitro studies confirmed that Twist1-overexpressing leukemic cells were more susceptible to cytarabine, but not daunorubicin, cytotoxicity. Our findings suggest that, in a subset of AML patients, Twist1 plays a prominent role in the pathogenesis of the disease that leads to unique clinical phenotypes. The result indicates that Twist1 could represent a powerful biomarker that serves as a prognostic as well as therapeutic guide for patients with AML. Disclosures No relevant conflicts of interest to declare.

In the mammalian central nervous system transcripts of certain synaptic components are localized near the synapse, allowing for rapid regulation of protein levels. Here we test whether an mRNA localization mechanism also exists in the postsynaptic specialization induced by agrin in C2C12 myotubes. RT-PCR showed that Chrna1 was co-purified with nicotinic acetylcholine receptor (AChR) isolated by affinity column or by ultracentrifugation. In addition, Stau1 was found to interact with Chrna1 mRNA, and knocking down of Stau1 by RNAi resulted in defective AChR clustering. These results suggest that mRNA localization also participates in the formation of mammalian neuromuscular junction (NMJ).Structured summary of protein interactionsAChR alpha 1physically interactswithStau1bypull down(View interaction)