The tumor suppressor genes MGMT and DAPK1 become methylated in several cancers including diffuse large B-cell lymphoma (DLBCL). However, allelic methylation patterns have not been investigated in ...DLBCL. We developed a fast and cost-efficient method for the analysis of allelic methylation based on pyrosequencing of methylation specific PCR (MSP) products including a SNP. Allelic methylation patterns were reliably analyzed in standards of known allelic methylation status even when diluted in unmethylated DNA to below 1% methylation. When studying 148 DLBCL patients MGMT and DAPK1 methylation was observed in 19% and 89%, respectively, and among methylated and heterozygous patients 29% and 55%, respectively, were biallelically methylated. An association between the T-allele of the rs16906252 SNP and MGMT methylation was observed (p-value=0.04), and DAPK1 methylation of the A-allele was associated with shorter overall survival (p-value=0.006). In future cancer research allelic MSP-pyrosequencing may be used to study a wide range of other loci.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
To evaluate patient characteristics and incidence of ophthalmic lymphoma in Denmark during the period 1980 to 2005.
All patients in Denmark with a diagnosis of ophthalmic lymphoma during the period ...1980 to 2005 were retrieved from three different population-based registries. Specimens from all patients were collected and reclassified according to the World Health Organization (WHO) classification system. Incidence rates were calculated by using Poisson regression models.
A total of 228 patients with a histologically verified diagnosis of ophthalmic lymphoma were included. There was an equal distribution of males and females. The most frequent lymphoma subtype was extranodal marginal zone B-cell lymphoma (MALT mucosa-associated lymphoid tissue lymphoma, 55.5%) and most cases were located in the orbit (56.8%). High-grade lymphoma subtypes were found more frequently in males than in females. Incidence rates were highly dependent on the patient's age. For all ages, a statistically significant annual average increase of 3.4% during the 26-year period was found. This increase was primarily due to a rise in the incidence of MALT lymphoma.
In the Danish population ophthalmic lymphoma consists primarily of orbital MALT lymphoma. Although it is a rare disease in mostly elderly patients, the incidence of ophthalmic lymphoma is increasing at a rapid pace.
For elderly patients with mantle cell lymphoma (MCL), there is no defined standard therapy. In this multicenter open-label phase I/II trial we evaluated the addition of lenalidomide (LEN) to ...rituximab-bendamustine (R-B) as first-line treatment to elderly MCL patients. Patients >65 years with untreated MCL, stage II-IV were eligible for inclusion. Primary endpoints were maximally tolerable dose (MTD) of LEN, and progression-free survival (PFS). Patients received six cycles q4w of L-B-R (L D1-14, B 90 mg/m(2) iv D1-2 and R 375 mg/m(2) iv D1) followed by single LEN (D1-21, q4w, cycles 7-13). 51 patients (median age 71 years) were enrolled 2009-2013. In phase I, the MTD of LEN was defined as 10 mg in cycles 2-6, and omitted in cycle 1. After six cycles, the complete remission rate (CRR) was 64% and 36% were MRD negative. At a median follow-up time of 31 months, median PFS was 42 months and 3 year overall survival was 73%. Infection was the most common non-hematological grade 3-5 event and occurred in 21 (42%) patients. Opportunistic infections occurred in three patients; 2 PCP and 1 CMV retinitis. Second primary malignancies (SPM) were observed in eight patients (16%). LEN could safely be combined with R-B, when added from the second cycle in patients with MCL, and was associated with a high rate of CR and molecular remission. However, we observed a high degree of severe infections and an unexpected high number of SPMs which may limit its use. http://clinicaltrials.gov: NCT00963534.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
OncomiRs miR-21 and miR-155 have been linked to lymphomagenesis, but information on their implication in diffuse large B-cell lymphoma (DLBCL) is limited. Here, we used locked nucleic acid-based in ...situ hybridization (ISH) detection techniques on formalin-fixed paraffin-embedded DLBCL tissue samples to identify miR-155 and miR-21 at the cellular level in 56 patients diagnosed with DLBCL, and compared them to miR array data. miR-155 was observed in tumor cells in 19/56 (33.9%) of the samples evaluated by ISH. miR-21 was localized to the stromal compartment in 41/56 (73.2%). A subset of these, 16/56 (28.6%), also showed labeling in tumor cells. When comparing ISH-scores and miR array data, miR-155 in tumor cells, identified by ISH, was associated with miR-155 expression in miR array data (P=0.030). Equally, miR-21 expression by miR array data were highly associated with miR-21 ISH-scores in the stromal cells (P=0.002), whereas no association between miR array data and ISH of miR-21 in tumor cells was observed (P=0.673). We found no association of miR-155 and miR-21 with overall survival or germinal center B-cell-like (GCB) versus non-GCB-like subtypes of DLBCL. In conclusion, miR-ISH added to the biological interpretation of miR expression in DLBCL compared with miR array data, but miR-155 and miR-21 ISH did not add prognostic information in this series.
is frequently mutated in different types of neoplasms including leukemia and lymphomas. Mutations of
have also been reported in mycosis fungoides (MF), the most common type of cutaneous lymphoma. ...However, little is known about the frequency, spectrum of mutations, and their prognostic significance in MF. In this study, we have optimized the protocol for Sanger sequencing of
using DNA extracted from archival paraffin-embedded biopsies. Of 19 samples from patients with stage IIB MF or higher, 31% harbored mutations in
. Overall survival of the patients with mutated
was significantly shorter than median survival in the age- and stage-matched patients treated in our Institution. Distribution of mutations was heterogenous in
exons; however, C > T transitions were common suggesting the causal role of ultraviolet radiation. We propose that
mutation status would be useful for risk stratification of patients with advanced MF.
Mantle cell lymphoma (MCL) has a heterogeneous clinical course and is mainly an aggressive B cell non-Hodgkin lymphoma; however, there are some indolent cases The Ki-67 index, defined by the ...percentage of Ki-67-positive lymphoma cells on histopathological slides, has been shown to be a very powerful prognostic biomarker. The pathology panel of the European MCL Network evaluated methods to assess the Ki-67 index including stringent counting, digital image analysis, and estimation by eyeballing. Counting of 2 × 500 lymphoma cells is the gold standard to assess the Ki-67 index since this value has been shown to predict survival in prospective randomized trials of the European MCL Network
.
Estimation by eyeballing and digital image analysis showed a poor concordance with the gold standard (concordance correlation coefficients CCC between 0.29 and 0.61 for eyeballing and CCC of 0.24 and 0.37 for two methods of digital image analysis, respectively). Counting a reduced number of lymphoma cells (2 × 100 cells) showed high interobserver agreement (CCC = 0.74). Pitfalls of the Ki-67 index are discussed and guidelines and recommendations for assessing the Ki-67 index in MCL are given.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
38.
Cancer genomics NORRILD, BODIL; GULDBERG, PER; RALFKIÆR, ELISABETH
APMIS : acta pathologica, microbiologica et immunologica Scandinavica,
October 2007, Volume:
115, Issue:
10
Journal Article
Peer reviewed
Open access
Almost all cells in the human body contain a complete copy of the genome with an estimated number of 25,000 genes. The sequences of these genes make up about three percent of the genome and comprise ...the inherited set of genetic information. The genome also contains information that determines when and where in the organism a given gene is active. This is the epigenetic information. Genomics is the study of DNA sequences and the epigenetic information of gene regulation.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
Diffuse large B‐cell lymphoma (DLBCL) is a frequent lymphoma subtype with a heterogeneous behavior and a variable response to conventional chemotherapy. This clinical diversity is believed to reflect ...differences in the molecular pathways leading to lymphomagenesis. In this study, we have analyzed pretreatment, diagnostic samples from 108 DLBCL by immunohistology for expression of four markers linked to germinal center B‐cells (CD10, Bcl‐6), postgerminal center B‐cells (MUM1) and apoptosis (Bcl‐2). The results indicate that both CD10 and Bcl‐6 are favorable prognostic indicators, in contrast to Bcl‐2, which is an adverse parameter. Furthermore, using two algorithms for distinction between low‐ and high‐risk patients proposed by Hans et al. (Blood, 2004; 103:275) and Muris et al. (Journal of Pathology, 2006; 208:714), it is shown that both are useful for predicting outcome in DLBCL. However, in this report, the algorithm of Hans et al. was superior to that of Muris et al. These findings confirm and extend other studies and indicate that different prognostic subgroups of DLBCL can be distinguished by simple immunohistological investigations for a limited number of markers. Whether these groups are also relevant for individual treatment decisions will be important to investigate in prospective studies.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
Allelic loss at chromosome 9q31–34 is a frequent event in many lymphoproliferative malignancies. Here, we examined DBC1 at 9q33.1 as a potential target in lymphomagenesis. DBC1 is a putative tumor ...suppressor that has been shown to be involved in the regulation of cell growth and programmed cell death. The methylation status of the DBC1 promoter CpG island was examined by methylation-specific PCR, bisulfite sequencing, and methylation-specific melting curve analysis. DBC1 was hypermethylated in 5 of 5 B-cell-derived lymphoma cell lines, 41 of 42 diffuse large B-cell lymphomas, 24 of 24 follicular lymphomas, 5 of 5 mantle cell lymphomas, 4 of 4 small lymphocytic lymphomas, 1 of 2 lymphoplasmacytoid lymphomas, and in 12 of 12 acute lymphoblastic leukemias, but was unmethylated in 1 case of splenic marginal zone lymphoma, in 12 of 12 multiple myelomas, in 24 of 24 reactive lymph nodes, and in 12 of 12 samples of blood lymphocytes from random donors. DBC1 hypermethylation was associated with transcriptional silencing in lymphoma cell lines, and reexpression of this gene could be induced by treatment with the demethylating agent, 5-aza-2′-deoxycytidine. Our data suggest that hypermethylation of the DBC1 promoter region is a frequent event during the development of lymphoproliferative malignancies, and that DBC1 hypermethylation may serve as a marker for these cancers.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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