An appropriate DNA input for bisulfite conversion reveals LINE-1 and Alu hypermethylation in tissues and circulating cell-free DNA from cancers.

The autonomous and active Long-Interspersed Element-1 (LINE-1, L1) and the non-autonomous Alu retrotransposon elements, contributing to 30% of the human genome, are the most abundant repeated sequences. With more than 90% of their sequences being methylated in normal cells, these elements undeniably...

Full description

Saved in:
Bibliographic Details
Main Authors: Trang Thi Quynh Tran, Tung The Pham, Than Thi Nguyen, Trang Hien Do, Phuong Thi Thu Luu, Uyen Quynh Nguyen, Linh Dieu Vuong, Quang Ngoc Nguyen, Son Van Ho, Hang Viet Dao, Tong Van Hoang, Lan Thi Thuong Vo
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2024-01-01
Series:PLoS ONE
Online Access:https://doi.org/10.1371/journal.pone.0316394
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1841533089525792768
author Trang Thi Quynh Tran
Tung The Pham
Than Thi Nguyen
Trang Hien Do
Phuong Thi Thu Luu
Uyen Quynh Nguyen
Linh Dieu Vuong
Quang Ngoc Nguyen
Son Van Ho
Hang Viet Dao
Tong Van Hoang
Lan Thi Thuong Vo
author_facet Trang Thi Quynh Tran
Tung The Pham
Than Thi Nguyen
Trang Hien Do
Phuong Thi Thu Luu
Uyen Quynh Nguyen
Linh Dieu Vuong
Quang Ngoc Nguyen
Son Van Ho
Hang Viet Dao
Tong Van Hoang
Lan Thi Thuong Vo
author_sort Trang Thi Quynh Tran
collection DOAJ
description The autonomous and active Long-Interspersed Element-1 (LINE-1, L1) and the non-autonomous Alu retrotransposon elements, contributing to 30% of the human genome, are the most abundant repeated sequences. With more than 90% of their sequences being methylated in normal cells, these elements undeniably contribute to the global DNA methylation level and constitute a major part of circulating-cell-free DNA (cfDNA). So far, the hypomethylation status of LINE-1 and Alu in cellular and extracellular DNA has long been considered a prevailing hallmark of ageing-related diseases and cancer. This study demonstrated that errors in LINE-1 and Alu methylation level measurements were caused by an excessive input quantity of genomic DNA used for bisulfite conversion. Using the minuscule DNA amount of 0.5 ng, much less than what has been used and recommended so far (500 ng-2 μg) or 1 μL of cfDNA extracted from 1 mL of blood, we revealed hypermethylation of LINE-1 and Alu in 407 tumour samples of primary breast, colon and lung cancers when compared with the corresponding pair-matched adjacent normal tissue samples (P < 0.05-0.001), and in cfDNA from 296 samples of lung cancers as compared with 477 samples from healthy controls (P < 0.0001). More importantly, LINE-1 hypermethylation in cfDNA is associated with healthy ageing. Our results have not only contributed to the standardized bisulfite-based protocols for DNA methylation assays, particularly in applications on repeated sequences but also provided another perspective for other repetitive sequences whose epigenetic properties may have crucial impacts on genome architecture and human health.
format Article
id doaj-art-5e02135ba31b4898bbce4c336442f36a
institution Kabale University
issn 1932-6203
language English
publishDate 2024-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj-art-5e02135ba31b4898bbce4c336442f36a2025-01-17T05:31:49ZengPublic Library of Science (PLoS)PLoS ONE1932-62032024-01-011912e031639410.1371/journal.pone.0316394An appropriate DNA input for bisulfite conversion reveals LINE-1 and Alu hypermethylation in tissues and circulating cell-free DNA from cancers.Trang Thi Quynh TranTung The PhamThan Thi NguyenTrang Hien DoPhuong Thi Thu LuuUyen Quynh NguyenLinh Dieu VuongQuang Ngoc NguyenSon Van HoHang Viet DaoTong Van HoangLan Thi Thuong VoThe autonomous and active Long-Interspersed Element-1 (LINE-1, L1) and the non-autonomous Alu retrotransposon elements, contributing to 30% of the human genome, are the most abundant repeated sequences. With more than 90% of their sequences being methylated in normal cells, these elements undeniably contribute to the global DNA methylation level and constitute a major part of circulating-cell-free DNA (cfDNA). So far, the hypomethylation status of LINE-1 and Alu in cellular and extracellular DNA has long been considered a prevailing hallmark of ageing-related diseases and cancer. This study demonstrated that errors in LINE-1 and Alu methylation level measurements were caused by an excessive input quantity of genomic DNA used for bisulfite conversion. Using the minuscule DNA amount of 0.5 ng, much less than what has been used and recommended so far (500 ng-2 μg) or 1 μL of cfDNA extracted from 1 mL of blood, we revealed hypermethylation of LINE-1 and Alu in 407 tumour samples of primary breast, colon and lung cancers when compared with the corresponding pair-matched adjacent normal tissue samples (P < 0.05-0.001), and in cfDNA from 296 samples of lung cancers as compared with 477 samples from healthy controls (P < 0.0001). More importantly, LINE-1 hypermethylation in cfDNA is associated with healthy ageing. Our results have not only contributed to the standardized bisulfite-based protocols for DNA methylation assays, particularly in applications on repeated sequences but also provided another perspective for other repetitive sequences whose epigenetic properties may have crucial impacts on genome architecture and human health.https://doi.org/10.1371/journal.pone.0316394
spellingShingle Trang Thi Quynh Tran
Tung The Pham
Than Thi Nguyen
Trang Hien Do
Phuong Thi Thu Luu
Uyen Quynh Nguyen
Linh Dieu Vuong
Quang Ngoc Nguyen
Son Van Ho
Hang Viet Dao
Tong Van Hoang
Lan Thi Thuong Vo
An appropriate DNA input for bisulfite conversion reveals LINE-1 and Alu hypermethylation in tissues and circulating cell-free DNA from cancers.
PLoS ONE
title An appropriate DNA input for bisulfite conversion reveals LINE-1 and Alu hypermethylation in tissues and circulating cell-free DNA from cancers.
title_full An appropriate DNA input for bisulfite conversion reveals LINE-1 and Alu hypermethylation in tissues and circulating cell-free DNA from cancers.
title_fullStr An appropriate DNA input for bisulfite conversion reveals LINE-1 and Alu hypermethylation in tissues and circulating cell-free DNA from cancers.
title_full_unstemmed An appropriate DNA input for bisulfite conversion reveals LINE-1 and Alu hypermethylation in tissues and circulating cell-free DNA from cancers.
title_short An appropriate DNA input for bisulfite conversion reveals LINE-1 and Alu hypermethylation in tissues and circulating cell-free DNA from cancers.
title_sort appropriate dna input for bisulfite conversion reveals line 1 and alu hypermethylation in tissues and circulating cell free dna from cancers
url https://doi.org/10.1371/journal.pone.0316394
work_keys_str_mv AT trangthiquynhtran anappropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT tungthepham anappropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT thanthinguyen anappropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT tranghiendo anappropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT phuongthithuluu anappropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT uyenquynhnguyen anappropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT linhdieuvuong anappropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT quangngocnguyen anappropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT sonvanho anappropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT hangvietdao anappropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT tongvanhoang anappropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT lanthithuongvo anappropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT trangthiquynhtran appropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT tungthepham appropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT thanthinguyen appropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT tranghiendo appropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT phuongthithuluu appropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT uyenquynhnguyen appropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT linhdieuvuong appropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT quangngocnguyen appropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT sonvanho appropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT hangvietdao appropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT tongvanhoang appropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers
AT lanthithuongvo appropriatednainputforbisulfiteconversionrevealsline1andaluhypermethylationintissuesandcirculatingcellfreednafromcancers