Biomaterial Database

Global promoter methylation analysis reveals novel candidate tumor suppressor genes in natural killer cell lymphoma. 2015

Can Küçük, and Xiaozhou Hu, and Bei Jiang, and David Klinkebiel, and Huimin Geng, and Qiang Gong, and Alyssa Bouska, and Javeed Iqbal, and Philippe Gaulard, and Timothy W McKeithan, and Wing C Chan

Department of Pathology, City of Hope National Medical Center, Duarte, California.

OBJECTIVE To identify tumor suppressor genes epigenetically silenced by promoter hypermethylation in extranodal natural killer cell lymphoma (NKCL). METHODS Promoter methylation was analyzed with global and locus-specific methylation assays in NKCL cases and NK cell lines. Gene expression profiles were used to identify genes for which aberrant promoter methylation was associated with transcriptional silencing. Selected DNA methylations were validated by RRBS, pyrosequencing, or q-MSP. Decitabine treatment was performed to evaluate reactivation of methylated genes. The tumor suppressor effect of silenced genes was evaluated functionally by reintroducing them into NK cell lines. RESULTS We observed significant promoter hypermethylation in most NKCL samples compared with normal NK cells. Correlation of global promoter methylation with gene expression profiles identified 95 genes with strong evidence for being silenced because of promoter methylation, including BCL2L11 (BIM), DAPK1, PTPN6 (SHP1), TET2, SOCS6, and ASNS. Known tumor suppressor genes were significantly overrepresented in this set of genes. Decitabine treatment of NK cell lines was associated with reexpression of all 10 selected methylated and silenced genes. Ectopic expression of frequently silenced BIM in two BIM-nonexpressing NK cell lines led to increased apoptosis and eventual elimination of BIM-transduced cells. It also sensitized these cell lines to chemotherapy-induced apoptosis. Similarly, reintroduction of SOCS6 significantly inhibited growth in SOCS6-nonexpressing NK cell lines. NK cell lines lacking ASNS expression showed increased sensitivity to treatment with l-asparaginase. Reintroduction of ASNS reduced drug sensitivity. CONCLUSIONS Promoter region hypermethylation is frequent in NKCL, and aberrantly methylated genes are pathologically and clinically significant.

UI	MeSH Term	Description	Entries
D011401	Promoter Regions, Genetic	DNA sequences which are recognized (directly or indirectly) and bound by a DNA-dependent RNA polymerase during the initiation of transcription. Highly conserved sequences within the promoter include the Pribnow box in bacteria and the TATA BOX in eukaryotes.	rRNA Promoter,Early Promoters, Genetic,Late Promoters, Genetic,Middle Promoters, Genetic,Promoter Regions,Promoter, Genetic,Promotor Regions,Promotor, Genetic,Pseudopromoter, Genetic,Early Promoter, Genetic,Genetic Late Promoter,Genetic Middle Promoters,Genetic Promoter,Genetic Promoter Region,Genetic Promoter Regions,Genetic Promoters,Genetic Promotor,Genetic Promotors,Genetic Pseudopromoter,Genetic Pseudopromoters,Late Promoter, Genetic,Middle Promoter, Genetic,Promoter Region,Promoter Region, Genetic,Promoter, Genetic Early,Promoter, rRNA,Promoters, Genetic,Promoters, Genetic Middle,Promoters, rRNA,Promotor Region,Promotors, Genetic,Pseudopromoters, Genetic,Region, Genetic Promoter,Region, Promoter,Region, Promotor,Regions, Genetic Promoter,Regions, Promoter,Regions, Promotor,rRNA Promoters
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D016147	Genes, Tumor Suppressor	Genes that inhibit expression of the tumorigenic phenotype. They are normally involved in holding cellular growth in check. When tumor suppressor genes are inactivated or lost, a barrier to normal proliferation is removed and unregulated growth is possible.	Antioncogenes,Cancer Suppressor Genes,Emerogenes,Genes, Cancer Suppressor,Genes, Growth Suppressor,Genes, Metastasis Suppressor,Growth Suppressor Genes,Metastasis Suppressor Genes,Tumor Suppressor Genes,Anti-Oncogenes,Genes, Onco-Suppressor,Oncogenes, Recessive,Tumor Suppressing Genes,Anti Oncogenes,Anti-Oncogene,Antioncogene,Cancer Suppressor Gene,Emerogene,Gene, Cancer Suppressor,Gene, Growth Suppressor,Gene, Metastasis Suppressor,Gene, Onco-Suppressor,Gene, Tumor Suppressing,Gene, Tumor Suppressor,Genes, Onco Suppressor,Genes, Tumor Suppressing,Growth Suppressor Gene,Metastasis Suppressor Gene,Onco-Suppressor Gene,Onco-Suppressor Genes,Oncogene, Recessive,Recessive Oncogene,Recessive Oncogenes,Suppressor Gene, Cancer,Suppressor Gene, Growth,Suppressor Gene, Metastasis,Suppressor Genes, Cancer,Suppressor Genes, Growth,Suppressor Genes, Metastasis,Tumor Suppressing Gene,Tumor Suppressor Gene
D054391	Lymphoma, Extranodal NK-T-Cell	An extranodal neoplasm, usually possessing an NK-cell phenotype and associated with EPSTEIN-BARR VIRUS. These lymphomas exhibit a broad morphologic spectrum, frequent necrosis, angioinvasion, and most commonly present in the midfacial region, but also in other extranodal sites.	Extranodal NK-T-Cell Lymphoma,Extranodal NK-T-Cell Lymphoma, Nasal,Extranodal NK-T-Cell Lymphoma, Nasal Type,Extranodal NK-T-Cell Lymphoma, Nasal and Nasal-Type,Extranodal NK T Cell Lymphoma,Extranodal NK T Cell Lymphoma, Nasal,Extranodal NK T Cell Lymphoma, Nasal Type,Extranodal NK T Cell Lymphoma, Nasal and Nasal Type,Extranodal NK-T-Cell Lymphomas,Lymphoma, Extranodal NK T Cell,Lymphomas, Extranodal NK-T-Cell,NK-T-Cell Lymphoma, Extranodal,NK-T-Cell Lymphomas, Extranodal
D059467	Transcriptome	The pattern of GENE EXPRESSION at the level of genetic transcription in a specific organism or under specific circumstances in specific cells.	Transcriptomes,Gene Expression Profiles,Gene Expression Signatures,Transcriptome Profiles,Expression Profile, Gene,Expression Profiles, Gene,Expression Signature, Gene,Expression Signatures, Gene,Gene Expression Profile,Gene Expression Signature,Profile, Gene Expression,Profile, Transcriptome,Profiles, Gene Expression,Profiles, Transcriptome,Signature, Gene Expression,Signatures, Gene Expression,Transcriptome Profile
D019175	DNA Methylation	Addition of methyl groups to DNA. DNA methyltransferases (DNA methylases) perform this reaction using S-ADENOSYLMETHIONINE as the methyl group donor.	DNA Methylations,Methylation, DNA,Methylations, DNA