DNA methylation profiling in breast cancer discordant identical twins identifies DOK7 as novel epigenetic biomarker.
Using whole blood from 15 twin pairs discordant for breast cancer and high-resolution (450K) DNA methylation analysis, we identified 403 differentially methylated CpG sites including known and novel potential breast cancer genes. Confirming the results in an independent validation cohort of 21 twin pairs determined the docking protein DOK7 as a candidate for blood-based cancer diagnosis.  DNA hypermethylation of the promoter region was also seen in primary breast cancer tissues and cancer cell lines. Hypermethylation of DOK7 occurs years before tumor diagnosis, suggesting a role as a powerful epigenetic blood-based biomarker as well as providing insights into breast cancer pathogenesis.
Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet, Barcelona, Catalonia 08907, Spain.
Holger
H
Heyn
F Javier
FJ
Carmona
Antonio
A
Gomez
Humberto J
HJ
Ferreira
Jordana T
JT
Bell
Sergi
S
Sayols
Kirsten
K
Ward
Olafur A
OA
Stefansson
Sebastian
S
Moran
Juan
J
Sandoval
Jorunn E
JE
Eyfjord
Tim D
TD
Spector
Manel
M
Esteller
D015415:Biomarkers / Q000378:metabolism*; D001943:Breast Neoplasms / Q000235:genetics*; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D005260:Female; D006801:Humans; D009124:Muscle Proteins / Q000235:genetics*; D018433:Twin Studies as Topic
D015415:Biomarkers; C511692:DOK7 protein, human; D009124:Muscle Proteins