Disruption of a -35 kb Enhancer Impairs CTCF Binding and MLH1 Expression in Colorectal Cells

Publication Date:
2018-09-15
Publisher:
The American Association for Cancer Research (AACR)
Print ISSN:
1078-0432
Electronic ISSN:
1557-3265
Topics:
Medicine
Published by:
http://www.aacr.org/
_version_ 1836399050311598080
autor Liu, Q., Thoms, J. A. I., Nunez, A. C., Huang, Y., Knezevic, K., Packham, D., Poulos, R. C., Williams, R., Beck, D., Hawkins, N. J., Ward, R. L., Wong, J. W. H., Hesson, L. B., Sloane, M. A., Pimanda, J. E.
beschreibung Purpose: MLH1 is a major tumor suppressor gene involved in the pathogenesis of Lynch syndrome and various sporadic cancers. Despite their potential pathogenic importance, genomic regions capable of regulating MLH1 expression over long distances have yet to be identified. Experimental Design: Here, we use chromosome conformation capture (3C) to screen a 650-kb region flanking the MLH1 locus to identify interactions between the MLH1 promoter and distal regions in MLH1 -expressing and nonexpressing cells. Putative enhancers were functionally validated using luciferase reporter assays, chromatin immunoprecipitation, and CRISPR-Cas9–mediated deletion of endogenous regions. To evaluate whether germline variants in the enhancer might contribute to impaired MLH1 expression in patients with suspected Lynch syndrome, we also screened germline DNA from a cohort of 74 patients with no known coding mutations or epimutations at the MLH1 promoter. Results: A 1.8-kb DNA fragment, 35 kb upstream of the MLH1 transcription start site enhances MLH1 gene expression in colorectal cells. The enhancer was bound by CTCF and CRISPR-Cas9–mediated deletion of a core binding region impairs endogenous MLH1 expression. A total of 5.4% of suspected Lynch syndrome patients have a rare single-nucleotide variant (G 〉 A; rs143969848; 2.5% in gnomAD European, non-Finnish) within a highly conserved CTCF-binding motif, which disrupts enhancer activity in SW620 colorectal carcinoma cells. Conclusions: A CTCF-bound region within the MLH1 -35 enhancer regulates MLH1 expression in colorectal cells and is worthy of scrutiny in future genetic screening strategies for suspected Lynch syndrome associated with loss of MLH1 expression. Clin Cancer Res; 24(18); 4602–11. ©2018 AACR .
citation_standardnr 6332655
datenlieferant ipn_articles
feed_id 9363
feed_publisher The American Association for Cancer Research (AACR)
feed_publisher_url http://www.aacr.org/
insertion_date 2018-09-15
journaleissn 1557-3265
journalissn 1078-0432
publikationsjahr_anzeige 2018
publikationsjahr_facette 2018
publikationsjahr_intervall 7984:2015-2019
publikationsjahr_sort 2018
publisher The American Association for Cancer Research (AACR)
quelle Clinical Cancer Research
relation http://clincancerres.aacrjournals.org/cgi/content/short/24/18/4602?rss=1
search_space articles
shingle_author_1 Liu, Q., Thoms, J. A. I., Nunez, A. C., Huang, Y., Knezevic, K., Packham, D., Poulos, R. C., Williams, R., Beck, D., Hawkins, N. J., Ward, R. L., Wong, J. W. H., Hesson, L. B., Sloane, M. A., Pimanda, J. E.
shingle_author_2 Liu, Q., Thoms, J. A. I., Nunez, A. C., Huang, Y., Knezevic, K., Packham, D., Poulos, R. C., Williams, R., Beck, D., Hawkins, N. J., Ward, R. L., Wong, J. W. H., Hesson, L. B., Sloane, M. A., Pimanda, J. E.
shingle_author_3 Liu, Q., Thoms, J. A. I., Nunez, A. C., Huang, Y., Knezevic, K., Packham, D., Poulos, R. C., Williams, R., Beck, D., Hawkins, N. J., Ward, R. L., Wong, J. W. H., Hesson, L. B., Sloane, M. A., Pimanda, J. E.
shingle_author_4 Liu, Q., Thoms, J. A. I., Nunez, A. C., Huang, Y., Knezevic, K., Packham, D., Poulos, R. C., Williams, R., Beck, D., Hawkins, N. J., Ward, R. L., Wong, J. W. H., Hesson, L. B., Sloane, M. A., Pimanda, J. E.
shingle_catch_all_1 Disruption of a -35 kb Enhancer Impairs CTCF Binding and MLH1 Expression in Colorectal Cells
Purpose: MLH1 is a major tumor suppressor gene involved in the pathogenesis of Lynch syndrome and various sporadic cancers. Despite their potential pathogenic importance, genomic regions capable of regulating MLH1 expression over long distances have yet to be identified. Experimental Design: Here, we use chromosome conformation capture (3C) to screen a 650-kb region flanking the MLH1 locus to identify interactions between the MLH1 promoter and distal regions in MLH1 -expressing and nonexpressing cells. Putative enhancers were functionally validated using luciferase reporter assays, chromatin immunoprecipitation, and CRISPR-Cas9–mediated deletion of endogenous regions. To evaluate whether germline variants in the enhancer might contribute to impaired MLH1 expression in patients with suspected Lynch syndrome, we also screened germline DNA from a cohort of 74 patients with no known coding mutations or epimutations at the MLH1 promoter. Results: A 1.8-kb DNA fragment, 35 kb upstream of the MLH1 transcription start site enhances MLH1 gene expression in colorectal cells. The enhancer was bound by CTCF and CRISPR-Cas9–mediated deletion of a core binding region impairs endogenous MLH1 expression. A total of 5.4% of suspected Lynch syndrome patients have a rare single-nucleotide variant (G > A; rs143969848; 2.5% in gnomAD European, non-Finnish) within a highly conserved CTCF-binding motif, which disrupts enhancer activity in SW620 colorectal carcinoma cells. Conclusions: A CTCF-bound region within the MLH1 -35 enhancer regulates MLH1 expression in colorectal cells and is worthy of scrutiny in future genetic screening strategies for suspected Lynch syndrome associated with loss of MLH1 expression. Clin Cancer Res; 24(18); 4602–11. ©2018 AACR .
Liu, Q., Thoms, J. A. I., Nunez, A. C., Huang, Y., Knezevic, K., Packham, D., Poulos, R. C., Williams, R., Beck, D., Hawkins, N. J., Ward, R. L., Wong, J. W. H., Hesson, L. B., Sloane, M. A., Pimanda, J. E.
The American Association for Cancer Research (AACR)
1078-0432
10780432
1557-3265
15573265
shingle_catch_all_2 Disruption of a -35 kb Enhancer Impairs CTCF Binding and MLH1 Expression in Colorectal Cells
Purpose: MLH1 is a major tumor suppressor gene involved in the pathogenesis of Lynch syndrome and various sporadic cancers. Despite their potential pathogenic importance, genomic regions capable of regulating MLH1 expression over long distances have yet to be identified. Experimental Design: Here, we use chromosome conformation capture (3C) to screen a 650-kb region flanking the MLH1 locus to identify interactions between the MLH1 promoter and distal regions in MLH1 -expressing and nonexpressing cells. Putative enhancers were functionally validated using luciferase reporter assays, chromatin immunoprecipitation, and CRISPR-Cas9–mediated deletion of endogenous regions. To evaluate whether germline variants in the enhancer might contribute to impaired MLH1 expression in patients with suspected Lynch syndrome, we also screened germline DNA from a cohort of 74 patients with no known coding mutations or epimutations at the MLH1 promoter. Results: A 1.8-kb DNA fragment, 35 kb upstream of the MLH1 transcription start site enhances MLH1 gene expression in colorectal cells. The enhancer was bound by CTCF and CRISPR-Cas9–mediated deletion of a core binding region impairs endogenous MLH1 expression. A total of 5.4% of suspected Lynch syndrome patients have a rare single-nucleotide variant (G > A; rs143969848; 2.5% in gnomAD European, non-Finnish) within a highly conserved CTCF-binding motif, which disrupts enhancer activity in SW620 colorectal carcinoma cells. Conclusions: A CTCF-bound region within the MLH1 -35 enhancer regulates MLH1 expression in colorectal cells and is worthy of scrutiny in future genetic screening strategies for suspected Lynch syndrome associated with loss of MLH1 expression. Clin Cancer Res; 24(18); 4602–11. ©2018 AACR .
Liu, Q., Thoms, J. A. I., Nunez, A. C., Huang, Y., Knezevic, K., Packham, D., Poulos, R. C., Williams, R., Beck, D., Hawkins, N. J., Ward, R. L., Wong, J. W. H., Hesson, L. B., Sloane, M. A., Pimanda, J. E.
The American Association for Cancer Research (AACR)
1078-0432
10780432
1557-3265
15573265
shingle_catch_all_3 Disruption of a -35 kb Enhancer Impairs CTCF Binding and MLH1 Expression in Colorectal Cells
Purpose: MLH1 is a major tumor suppressor gene involved in the pathogenesis of Lynch syndrome and various sporadic cancers. Despite their potential pathogenic importance, genomic regions capable of regulating MLH1 expression over long distances have yet to be identified. Experimental Design: Here, we use chromosome conformation capture (3C) to screen a 650-kb region flanking the MLH1 locus to identify interactions between the MLH1 promoter and distal regions in MLH1 -expressing and nonexpressing cells. Putative enhancers were functionally validated using luciferase reporter assays, chromatin immunoprecipitation, and CRISPR-Cas9–mediated deletion of endogenous regions. To evaluate whether germline variants in the enhancer might contribute to impaired MLH1 expression in patients with suspected Lynch syndrome, we also screened germline DNA from a cohort of 74 patients with no known coding mutations or epimutations at the MLH1 promoter. Results: A 1.8-kb DNA fragment, 35 kb upstream of the MLH1 transcription start site enhances MLH1 gene expression in colorectal cells. The enhancer was bound by CTCF and CRISPR-Cas9–mediated deletion of a core binding region impairs endogenous MLH1 expression. A total of 5.4% of suspected Lynch syndrome patients have a rare single-nucleotide variant (G > A; rs143969848; 2.5% in gnomAD European, non-Finnish) within a highly conserved CTCF-binding motif, which disrupts enhancer activity in SW620 colorectal carcinoma cells. Conclusions: A CTCF-bound region within the MLH1 -35 enhancer regulates MLH1 expression in colorectal cells and is worthy of scrutiny in future genetic screening strategies for suspected Lynch syndrome associated with loss of MLH1 expression. Clin Cancer Res; 24(18); 4602–11. ©2018 AACR .
Liu, Q., Thoms, J. A. I., Nunez, A. C., Huang, Y., Knezevic, K., Packham, D., Poulos, R. C., Williams, R., Beck, D., Hawkins, N. J., Ward, R. L., Wong, J. W. H., Hesson, L. B., Sloane, M. A., Pimanda, J. E.
The American Association for Cancer Research (AACR)
1078-0432
10780432
1557-3265
15573265
shingle_catch_all_4 Disruption of a -35 kb Enhancer Impairs CTCF Binding and MLH1 Expression in Colorectal Cells
Purpose: MLH1 is a major tumor suppressor gene involved in the pathogenesis of Lynch syndrome and various sporadic cancers. Despite their potential pathogenic importance, genomic regions capable of regulating MLH1 expression over long distances have yet to be identified. Experimental Design: Here, we use chromosome conformation capture (3C) to screen a 650-kb region flanking the MLH1 locus to identify interactions between the MLH1 promoter and distal regions in MLH1 -expressing and nonexpressing cells. Putative enhancers were functionally validated using luciferase reporter assays, chromatin immunoprecipitation, and CRISPR-Cas9–mediated deletion of endogenous regions. To evaluate whether germline variants in the enhancer might contribute to impaired MLH1 expression in patients with suspected Lynch syndrome, we also screened germline DNA from a cohort of 74 patients with no known coding mutations or epimutations at the MLH1 promoter. Results: A 1.8-kb DNA fragment, 35 kb upstream of the MLH1 transcription start site enhances MLH1 gene expression in colorectal cells. The enhancer was bound by CTCF and CRISPR-Cas9–mediated deletion of a core binding region impairs endogenous MLH1 expression. A total of 5.4% of suspected Lynch syndrome patients have a rare single-nucleotide variant (G > A; rs143969848; 2.5% in gnomAD European, non-Finnish) within a highly conserved CTCF-binding motif, which disrupts enhancer activity in SW620 colorectal carcinoma cells. Conclusions: A CTCF-bound region within the MLH1 -35 enhancer regulates MLH1 expression in colorectal cells and is worthy of scrutiny in future genetic screening strategies for suspected Lynch syndrome associated with loss of MLH1 expression. Clin Cancer Res; 24(18); 4602–11. ©2018 AACR .
Liu, Q., Thoms, J. A. I., Nunez, A. C., Huang, Y., Knezevic, K., Packham, D., Poulos, R. C., Williams, R., Beck, D., Hawkins, N. J., Ward, R. L., Wong, J. W. H., Hesson, L. B., Sloane, M. A., Pimanda, J. E.
The American Association for Cancer Research (AACR)
1078-0432
10780432
1557-3265
15573265
shingle_title_1 Disruption of a -35 kb Enhancer Impairs CTCF Binding and MLH1 Expression in Colorectal Cells
shingle_title_2 Disruption of a -35 kb Enhancer Impairs CTCF Binding and MLH1 Expression in Colorectal Cells
shingle_title_3 Disruption of a -35 kb Enhancer Impairs CTCF Binding and MLH1 Expression in Colorectal Cells
shingle_title_4 Disruption of a -35 kb Enhancer Impairs CTCF Binding and MLH1 Expression in Colorectal Cells
timestamp 2025-06-30T23:36:48.243Z
titel Disruption of a -35 kb Enhancer Impairs CTCF Binding and MLH1 Expression in Colorectal Cells
titel_suche Disruption of a -35 kb Enhancer Impairs CTCF Binding and MLH1 Expression in Colorectal Cells
topic WW-YZ
uid ipn_articles_6332655