Project description:Recent studies show that mantle cell lymphoma (MCL) express aberrant miRNA profiles, however, the clinical effect of miRNA expression has not previously been examined and validated in prospective, large, homogenously treated cohorts. We analyzed diagnostic MCL samples from the Nordic MCL2 and MCL3 clinical trials, in which all patients had received Rituximab-high-dose cytarabin alternating with Rituximab-maxiCHOP, followed by BEAM and autologous stem cell support. We performed genome-wide miRNA microarray profiling of 74 diagnostic MCL samples from the MCL2 trial (screening cohort). Differentially expressed miRNAs were re-analyzed by qRT-PCR. Prognostic miRNAs were validated by qRT-PCR in diagnostic MCL samples from 94 patients of the independent MCL3 trial (validation cohort). Three miRNAs (miR-18b, miR-92a, miR-378d) were significantly differentially expressed in patients who died from MCL in both the screening- and the validation cohort. MiR-18b was superior to miR-92a and miR-378d in predicting high risk. Thus, we generated a new MIPI-B-miR prognosticator, combining expression-levels of miR-18b with MIPI-B data. This prognosticator improved identification of high risk patients compared to MIPI-B with regard to cause-specific survival (P=0.015), overall survival (P=0.006) and progression-free survival (P<0.001). Transfection of two MCL cell lines with miR-18b decreased their proliferation rate without inducing apoptosis, suggesting miR-18b may render MCL cells resistant to chemotherapy by decelerating cell proliferation. Thus, we conclude that overexpression of miR-18b identifies patients with poor prognosis in two large prospective MCL cohorts and adds prognostic information to MIPI-B. MiR-18b may reduce the proliferation rate of MCL cells as a mechanism of chemoresistance.
Project description:Mantle cell lymphoma (MCL) is an aggressive neoplasm with poor outcome. However, some patients have an indolent disease (iMCL) and may not require intensive treatment at initial diagnosis. Diagnostic criteria to recognize these patients are not available. We hypothesized that the analysis of the genetic and expression features of the tumors may help to identify patients with an indolent clinical evolution and provide biomarkers that could be used in the clinical setting.
Project description:Mantle cell lymphoma (MCL) is an aggressive neoplasm with poor outcome. However, some patients have an indolent disease (iMCL) and may not require intensive treatment at initial diagnosis. Diagnostic criteria to recognize these patients are not available. We hypothesized that the analysis of the genetic and expression features of the tumors may help to identify patients with an indolent clinical evolution and provide biomarkers that could be used in the clinical setting. Seven patients with an iMCL that did not require chemotherapy for more than 2 years were compared to 15 conventional MCL (cMCL) that needed systemic therapy at diagnosis. MCL were compared with other leukemic lymphoid neoplasms including 17 CLL, 7FL, HCL and 2HCLv.
Project description:The proliferation gene expression signature is a quantitative integrator of oncogenic events that predicts survival in mantle cell lymphoma Keywords: lymphochip; MCL; untreated Tumor biopsies from 71 untreated patients with mantle cell lymphoma
Project description:Purpose: Follicular lymphoma is a common lymphoma of adults. Although its course is often indolent, a substantial proportion of patients have a poor prognosis, often due to rapid progression or transformation to a more aggressive lymphoma. Currently available clinical prognostic scores, such as the follicular lymphoma international prognostic index, are not able to optimally predict transformation or poor outcome. Experimental Design: Gene expression profiling was done on primary lymphoma biopsy samples. Results: Using a statistically conservative approach, predictive interaction analysis, we have identified pairs of interacting genes that predict poor outcome, measured as death within 5 years of diagnosis. The best gene pair performs >1,000-fold better than any single gene or the follicular lymphoma international prognostic index in our data set. Many gene pairs achieve outcome prediction accuracies exceeding 85% in extensive cross-validation and noise sensitivity computational analyses.Many genes repeatedly appear in top-ranking pairs, suggesting that they reproducibly provide predictive capability. Conclusions:The evidence reported here may provide the basis for an expression-based, multigene test for predicting poor follicular lymphoma outcomes. Keywords: Comparative genomics
Project description:Functional studies to investigate gene mutations recurrent in B cell lymphoma have been hampered by the inability to genetically manipulate primary cells, attributed to low transduction efficacy and procedure-associated toxicity. Alternative approaches utilize cell lines and mouse models, which often only poorly represent the genomic complexity and biology of the primary malignancy. To overcome these limitations, we have developed a method to retrovirally transfer genes into primary malignant B cells with high transduction efficacy and minimal toxicity. Using this method, we investigated the functions of NOTCH1, the most commonly mutated gene in CLL, by generating isogenic primary tumor cells from patients with Chronic Lymphocytic Leukemia (CLL) and Mantle Cell Lymphoma (MCL), differing only in their expression of NOTCH1. Our data demonstrate that NOTCH1 facilitates immune escape of malignant B cells by up-regulating PD-L1, partly dependent on autocrine interferon-g signaling. In addition, NOTCH1 causes silencing of the entire HLA-class II locus via suppression of the transcriptional co-activator CIITA. These NOTCH1-mediated immune escape mechanisms are associated with the expansion of CD4+ T cells in vivo, further contributing to the poor clinical outcome of NOTCH1-mutated CLL and MCL
Project description:The stabilization of MYCN by FOXR2 represents an alternative mechanism to MYCN amplification to increase MYCN protein levels. As such, FOXR2 expression identifies another subset of neuroblastoma patients with unfavorable clinical outcome. Background: Clinical outcomes of neuroblastoma patients range from spontaneous tumor regression to fatality. Hence, understanding the mechanisms that cause tumor progression are crucial for the treatment of patients. In this study, we show that FOXR2 activation identifies a subset of neuroblastoma tumors with unfavorable outcome and we investigate the mechanism how FOXR2 relates to poor outcome in patients.
Project description:Aberrant expression of microRNA (miRNA) is closely associated with carcinogenesis. The malignancy of the hepatocellular carcinoma (HCC) is prescribed in the degree of histological differentiation. Poorly differentiated HCC is generally more malignant prognosis than well differentiated HCC. We analyzed the miRNA expression profiles in 110 HCC (60 moderately differentiated, 30 poorly differentiated, and 20 well differentiated HCC) by using microarray in order to establish the novel biomarker for the degree of histological differentiation and forecasting relapse of HCC. The expression level of 12 miRNAs was significantly different according to the degree of histological differentiation. The expression level of miR-18b in poorly differentiated HCC was significantly higher than that in well differentiated HCC. Based on the target search algorithm and argonaute 2 (Ago2) immunoprecipitation study for target binding assay, miR-18b can control the expression of trinucleotide repeat containing 6B (TNRC6B) as a target. Over expression of miR-18b and down regulation of TNRC6B accelerated the activity of cell proliferation and lost ability of cell adhesion in two hepatoma cell lines. Low expression of miR-18b is significantly decreased the relapse free rate after surgical resection. In conclusion, expression pattern of miR-18b is a marker of an important determinant in the control of cell proliferation and adhesion and also prediction of clinical course. From a clinical point of view, our study emphasizes miR-18b as a diagnostic and prognostic marker for HCC progression.
Project description:The RNA-seq data presented in this study include libraries from Mantle Cell Lymphoma (MCL) tumor cells sequentially obtained from patients
Project description:Mantle Cell Lymphoma (MCL) is a mostly incurable malignancy arising from naïve B cells (NBC) in the mantle zone of lymph node follicles. We analyzed genome-wide methylation in MCL patients using the HELP (Hpa II tiny fragment Enrichment by Ligation mediated PCR) assay and found significant aberrancy in promoter methylation patterns as compared to normal NBCs. Using biological and stringent statistical criteria, we further identified four hypermethylated genes CDKN2B, MLF-1, PCDH8, HOXD8 and four hypomethylated genes CD37, HDAC1, NOTCH1 and CDK5 where aberrant methylation was associated with inverse changes in mRNA levels. MassArray Epityper analysis confirmed the presence of differential methylation at the promoter region of these genes. Immunohistochemical analysis of an independent cohort of 14 MCL patient samples, confirmed CD37 surface expression in 93% of patients, validating its selection as a target for MCL therapy. Treatment of MCL cell lines with a novel small modular immunopharmaceutical(CD37-SMIP) resulted in significant loss of viability in cell lines with intense surface CD37 expression. Treatment of MCL cell lines with the DNA methyltransferase inhibitor decitabine resulted in reversal of aberrant hypermethylation and synergized with the HDAC inhibitor SAHA in induction of the four hypermethylated genes CDKN2B, MLF-1, PCDH8 and HOXD8. The combination of Decitabine and SAHA also resulted in potent and synergistic anti-MCL cytotoxicity as compared to either drug alone. In conclusion, our analysis shows prominent and aberrant methylation of the MCL genome and identifies novel differentially methylated and expressed genes in MCL cell lines and patient samples. Furthermore, our data suggest that differentially methylated genes can be targeted for therapeutic benefit in MCL. Gene expression profiling by array comprised of 8 mantle cell lymphoma (MCL) cell lines and 8 leukemic blast from blood from patients newly diagnosed with MCL. Unbiased genome-wide analysis of DNA methylation in leukemic blast from peripheral blood or pheresis products from 22 patients newly diagnosed with mantle cell lymphoma (MCL) prior to any treatment. 10 IgD+ Na ve B cells from specimens from healthy donors undergoing routine tonsillectomy were used as appropriate controls. Methylation patterns of 13 MCL cell lines were also compared.