Mice Lacking a Myc Enhancer Element that Includes Human SNP rs6983267 Are Resistant to Intestinal Tumors
Ontology highlight
ABSTRACT: Multiple cancer-associated single nucleotide polymorphisms (SNPs) have been mapped to conserved sequences within a 500 kilobase region upstream of the MYC oncogene on human chromosome 8q24. These SNPs may affect cancer development through altered regulation of MYC expression, but this hypothesis has been difficult to confirm. We generated mice deficient in Myc-335, a putative MYC regulatory element that contains rs6983267, a SNP accounting for more human cancer- related morbidity than any other genetic variant or mutation. In Myc-335 null mice, Myc transcripts were expressed in the intestinal crypts in a pattern similar to that in wild-type mice but at modestly reduced levels. The mutant mice displayed no overt phenotype but were markedly resistant to intestinal tumorigenesis induced by the APCmin mutation. These results establish that a cancer-associated SNP identified in human genome-wide association studies has a functional effect in vivo. Exon-array analysis of mouse colon tissues from Myc-335 null and wild-type mouse (both mice are male and from the same litter). Related ChIP-seq data available in Short Read Archive, Accession ERP001919
Project description:Multiple cancer-associated single nucleotide polymorphisms (SNPs) have been mapped to conserved sequences within a 500 kilobase region upstream of the MYC oncogene on human chromosome 8q24. These SNPs may affect cancer development through altered regulation of MYC expression, but this hypothesis has been difficult to confirm. We generated mice deficient in Myc-335, a putative MYC regulatory element that contains rs6983267, a SNP accounting for more human cancer- related morbidity than any other genetic variant or mutation. In Myc-335 null mice, Myc transcripts were expressed in the intestinal crypts in a pattern similar to that in wild-type mice but at modestly reduced levels. The mutant mice displayed no overt phenotype but were markedly resistant to intestinal tumorigenesis induced by the APCmin mutation. These results establish that a cancer-associated SNP identified in human genome-wide association studies has a functional effect in vivo.
Project description:To identified the method which can differentiate in situ SNP modification, we constructed an RNAseq library to identify SNPs in the C6 cell line and parent-specific SNPs in the PVN of C57. Design probes for these SNPs for in situ SNP detection and was applied to detect tumor driver genes mutation and allele specific expression of parental genes.
Project description:A core task to understand the consequences of non-coding single nucleotide polymorphisms (SNP) is to identify their genotype specific binding of transcription factor (TF). Here, we generate a large-scale TF-SNP interaction map for a selection of 116 colorectal cancer (CRC) risk loci and validated TF binding to 10 putatively functional SNPs. Our data further revealed TF binding complexity adjacent to the 116 risk loci, adding an additional layer of understanding to regulatory networks associated with CRC relevant loci.
Project description:The Malaysian Node of the Human Variome Project Database (MyHVPDb) is a country specific database of human variant and gene mutation that was established in 2011. This ethnic specific mutation and variation databases are being continuously updated, recording extensive information over the genetic heterogeneity of the Malaysian ethnic groups. The database comprises of SNP Database and Mutation Database. The SNP database has stored 291718 SNPs that was obtained by genotyping the SNPs of 101 healthy individuals from six Malay sub-ethnic groups which consist of Malay Kelantan, Malay Banjar, Malay Kedah, Malay Jawa, Malay Bugis and Malay Champa.
Project description:The Malaysian Node of the Human Variome Project Database (MyHVPDb) is a country specific database of human variant and gene mutation that was established in 2011. This ethnic specific mutation and variation databases are being continuously updated, recording extensive information over the genetic heterogeneity of the Malaysian ethnic groups. The database comprises of SNP Database and Mutation Database. The SNP database has stored 291718 SNPs that was obtained by genotyping the SNPs of 101 healthy individuals from six Malay sub-ethnic groups which consist of Malay Kelantan, Malay Banjar, Malay Kedah, Malay Jawa, Malay Bugis and Malay Champa. Affymetrix SNP arrays were performed according to the manufacturer's directions on DNA extracted from blood samples.
Project description:A core task to understand the consequences of non-coding single nucleotide polymorphisms (SNP) is to identify their genotype specific binding of transcription factor (TF). Here, we generate a large-scale TF-SNP interaction map for a selection of 116 colorectal cancer (CRC) risk loci and validated TF binding to 10 putatively functional SNPs. Our data further revealed TF binding complexity adjacent to the 116 risk loci, adding an additional layer of understanding to regulatory networks associated with CRC relevant loci.
Project description:To understand the molecular mechanism of rectal cancer and develop markers for disease prognostication, we generated and explored a dataset from 243 rectal cancer patients by gene expression microarray analysis of cancer samples and matched controls, and SNP-arrays of germline DNA. We found that two of the loci most strongly linked with colorectal cancer (CRC) risk, 8q24 (upstream of MYC) and 18q21 (in the intron of SMAD7), as well as 20q13 (in the intron of LAMA5), are tightly associated with the prognosis of rectal cancer patients. For SNPs on 18q21 (rs12953717 and rs4464148) and 20q13 (rs4925386), alleles that correlate with higher risk for the development of CRC are associated with shorter disease free survival (DFS). However, for rs6983267 on 8q24, the low risk allele is associated with a higher risk for recurrence and metastasis after surgery, and importantly, is strongly correlated with the resistance of CRC cell lines to chemoradiotherapy (CRT). We also found that although MYC expression is dramatically increased in cancer, patients with higher levels of MYC have a better prognosis. The expression of SMAD7 is weakly correlated with DFS. Notably, the presence of the 8q24 and 18q21 SNP alleles is not correlated with expression levels of MYC and SMAD7. rs4464148, and probably rs6983267 and rs4925386, are linked with overall survival time of patients. In conclusion, we show that several CRC risk SNPs detect subpopulations of rectal cancer patients with poor prognosis, and that rs6983267 probably affects prognosis through interfering with the resistance of cancer cells to CRT.
Project description:We adapted the DiR barcode-based parallel reporter assay systems strategy to systematically identify the breast cancer related SNPs that affect gene expression by modulating activities of regulatory elements. Among 293 SNPs linked with GWAS-identified breast cancer-risk SNPs, we found seven functional regulatory SNPs in MCF7 cells. Further mechanism study indicates that one SNP regulates gene expression in breast cancer malignancy. The DiR system has great potential to advance the functional study of risk SNPs that have associations with polygenic diseases. Our findings hold great promise in benefiting breast cancer patients with prognostic prediction.
Project description:We adapted the DiR barcode-based parallel reporter assay systems strategy to systematically identify the SNPs that affect gene expression by modulating activities of regulatory elements. Among 293 SNPs linked with GWAS-identified prostate cancer-risk SNPs, we found 32, 9, and 11 regulatory SNPs in 22Rv1, PC-3, and LNCaP cells. Further mechanism study indicates that one SNP regulates gene expression in prostate cancer malignancy. The DiR system has great potential to advance the functional study of risk SNPs that have associations with polygenic diseases. Our findings hold great promise in benefiting prostate cancer patients with prognostic prediction.
Project description:We created mice, which are deficient for Myc specifically in cardiac myocytes by crossing crossed Myc-floxed mice (Mycfl/fl) and MLC-2VCre/+ mice. Serial analysis of earlier stages of gestation revealed that Myc-deficient mice died prematurely at E13.5-14.5. Morphological analyses of E13.5 Myc-null embryos showed normal ventricular size and structure; however, decreased cardiac myocyte proliferation and increased apoptosis was observed. BrdU incorporation rates were also decreased significantly in Myc-null myocardium. Myc-null mice displayed a 3.67-fold increase in apoptotic cardiomyocytes by TUNEL assay. We examined global gene expression using oligonucleotide microarrays. Numerous genes involved in mitochondrial death pathways were dysregulated including Bnip3L and Birc2. Keywords: wildtype vs Myc-null