Project description:This SuperSeries is composed of the following subset Series: GSE30336: Expression analysis of 52 glioma clinical samples (36 CIMP+ and 16 CIMP-) and 6 cell line samples GSE30338: Methylation analysis of 81 glioma clinical samples (49 CIMP+ and 32 CIMP-) and 53 cell line samples Refer to individual Series
Project description:Glioma CIMP (G-CIMP) is a powerful determinant of tumor pathogenicity but the molecular cause of G-CIMP is a fundamental question that is unresolved. Here, we show that mutation of a single gene, isocitrate dehydrogenase 1 (IDH1), directly causes the G-CIMP in gliomas by remodeling the methylome. In this study 52 glioma clinic samples (36 CIMP+ and 16 CIMP-) were analyzed. Parental IDH1 wild-type and IDH1 mutant cells were passaged 40 and passage 40 were cell line was sent for expression array.
Project description:Glioma CIMP (G-CIMP) is a powerful determinant of tumor pathogenicity but the molecular cause of G-CIMP is a fundamental question that is unresolved. Here, we show that mutation of a single gene, isocitrate dehydrogenase 1 (IDH1), directly causes the G-CIMP in gliomas by remodeling the methylome. In this study 81 glioma clinic samples (49 CIMP+ and 32 CIMP-) were analyzed. Parental IDH1 wild-type and IDH1 mutant cells were passaged until passage 50.
Project description:Glioma CIMP (G-CIMP) is a powerful determinant of tumor pathogenicity but the molecular cause of G-CIMP is a fundamental question that is unresolved. Here, we show that mutation of a single gene, isocitrate dehydrogenase 1 (IDH1), directly causes the G-CIMP in gliomas by remodeling the methylome.
Project description:Glioma CIMP (G-CIMP) is a powerful determinant of tumor pathogenicity but the molecular cause of G-CIMP is a fundamental question that is unresolved. Here, we show that mutation of a single gene, isocitrate dehydrogenase 1 (IDH1), directly causes the G-CIMP in gliomas by remodeling the methylome.
Project description:In short: The objective with the gene expression array (Illumina HT-12 v.4) analysis of 17 T-ALL samples was to correlate gene expression levels with DNA promoter methylation status. Manuscript Abstract: Background: Treatment of pediatric T-cell acute lymphoblastic leukemia (T-ALL) has improved, but there is a considerable fraction of patients experiencing a poor outcome. There is a need for better prognostic markers and aberrant DNA methylation is a candidate in other malignancies, but its potential prognostic significance in T-ALL is hitherto undecided. Design and Methods: Genome wide promoter DNA methylation analysis was performed in pediatric T-ALL samples (n=43) using arrays covering >27000 CpG sites. Clinical outcome was evaluated in relation to methylation status and compared with a contemporary T-ALL group not tested for methylation (n= 32). Results: Based on CpG island methylator phenotype (CIMP), T-ALL samples were subgrouped as CIMP+ (high methylation) and CIMP- (low methylation). CIMP- T-ALL patients had significantly worse overall and event free survival (p=0.02 and p=0.001, respectively) compared to CIMP+ cases. CIMP status was an independent factor for survival in multivariate analysis including age, gender and white blood cell count. Analysis of differently methylated genes in the CIMP subgroups showed an overrepresentation of transcription factors, ligands and polycomb target genes. Conclusions: We identified global promoter methylation profiling as being of relevance for subgrouping and prognostication of pediatric T-ALL.
Project description:In short: Genome wide promoter DNA methylation profiling of 43 T-ALL samples and 5 T-cell controls (normal bone marrow and stimulated T-cells) . The Illumina Infinium 27k Human DNA methylation Beadchip v1.2 was used to obtain DNA methylation profiles across approximately 27,000 CpGs. Manuscript abstract: Background: Treatment of pediatric T-cell acute lymphoblastic leukemia (T-ALL) has improved, but there is a considerable fraction of patients experiencing a poor outcome. There is a need for better prognostic markers and aberrant DNA methylation is a candidate in other malignancies, but its potential prognostic significance in T-ALL is hitherto undecided. Design and Methods: Genome wide promoter DNA methylation analysis was performed in pediatric T-ALL samples (n=43) using arrays covering >27000 CpG sites. Clinical outcome was evaluated in relation to methylation status and compared with a contemporary T-ALL group not tested for methylation (n= 32). Results: Based on CpG island methylator phenotype (CIMP), T-ALL samples were subgrouped as CIMP+ (high methylation) and CIMP- (low methylation). CIMP- T-ALL patients had significantly worse overall and event free survival (p=0.02 and p=0.001, respectively) compared to CIMP+ cases. CIMP status was an independent factor for survival in multivariate analysis including age, gender and white blood cell count. Analysis of differently methylated genes in the CIMP subgroups showed an overrepresentation of transcription factors, ligands and polycomb target genes. Conclusions: We identified global promoter methylation profiling as being of relevance for subgrouping and prognostication of pediatric T-ALL.
Project description:Purpose: The long-term follow-up results from the EORTC-26951 trial showed that the addition of PCV after radiotherapy increases survival in anaplastic oligodendrogliomas/oligoastrocytomas (AOD/AOA). However, some patients appeared to benefit more from PCV treatment than others. Experimental Design: We performed genome-wide methylation profiling of 115 samples included in the EORTC-26951 trial and extracted the CpG island hypermethylated phenotype (CIMP) and MGMT promoter methylation (MGMT-STP27) status. Results: We first demonstrate that methylation profiling can be performed on archival tissues with a performance that is similar to snap frozen tissue samples. We then performed methylation profiling on EORTC-26951 clinical trial samples. Univariate analysis indicated that CIMP+ or MGMT-STP27 methylated tumors had an improved survival compared to CIMP- and/or MGMT-STP27 unmethylated tumors (median overall survival (OS) 1.05 v. 6.46 years and 1.06 v. 3.8 years, both P<0.0001 for CIMP and MGMT-STP27 status respectively). Multivariable analysis indicates that CIMP and MGMT-STP27 are significant prognostic factors for survival in presence of age, sex performance score and review diagnosis in the model.Multivariate analysis indicates that CIMP and MGMT-STP27 status are prognostic factors for survival independent of age, sex, performance score and review diagnosis. CIMP+ and MGMT-STP27 methylated tumors showed a clear benefit from adjuvant PCV chemotherapy: the median OS of CIMP+ samples in the RT and RT-PCV arms was 3.27 and 9.51 years respectively P=0.0033; for MGMT-STP27 methylated samples it was 1.98 and 8.65 years. There was no such benefit for CIMP- or for MGMT-STP27 unmethylated tumors. MGMT-STP27 status remained significant in an interaction test (P=0.003). Statistical analysis of microarray (SAM) identified 259 novel CpGs associated with treatment response. Conclusions: MGMT-STP27 may be used to guide treatment decisions in this tumor type.
Project description:Purpose: The long-term follow-up results from the EORTC-26951 trial showed that the addition of PCV after radiotherapy increases survival in anaplastic oligodendrogliomas/oligoastrocytomas (AOD/AOA). However, some patients appeared to benefit more from PCV treatment than others. Experimental Design: We performed genome-wide methylation profiling of 115 samples included in the EORTC-26951 trial and extracted the CpG island hypermethylated phenotype (CIMP) and MGMT promoter methylation (MGMT-STP27) status. Results: We first demonstrate that methylation profiling can be performed on archival tissues with a performance that is similar to snap frozen tissue samples. We then performed methylation profiling on EORTC-26951 clinical trial samples. Univariate analysis indicated that CIMP+ or MGMT-STP27 methylated tumors had an improved survival compared to CIMP- and/or MGMT-STP27 unmethylated tumors (median overall survival (OS) 1.05 v. 6.46 years and 1.06 v. 3.8 years, both P<0.0001 for CIMP and MGMT-STP27 status respectively). Multivariable analysis indicates that CIMP and MGMT-STP27 are significant prognostic factors for survival in presence of age, sex performance score and review diagnosis in the model.Multivariate analysis indicates that CIMP and MGMT-STP27 status are prognostic factors for survival independent of age, sex, performance score and review diagnosis. CIMP+ and MGMT-STP27 methylated tumors showed a clear benefit from adjuvant PCV chemotherapy: the median OS of CIMP+ samples in the RT and RT-PCV arms was 3.27 and 9.51 years respectively P=0.0033; for MGMT-STP27 methylated samples it was 1.98 and 8.65 years. There was no such benefit for CIMP- or for MGMT-STP27 unmethylated tumors. MGMT-STP27 status remained significant in an interaction test (P=0.003). Statistical analysis of microarray (SAM) identified 259 novel CpGs associated with treatment response. Conclusions: MGMT-STP27 may be used to guide treatment decisions in this tumor type.