Age-related methylation in normal colon mucosa differs between the proximal and distal colon in patients who underwent colonoscopy.
OBJECTIVE
To examine the difference in the methylation status in normal colon mucosa between the proximal and distal colon, in relation to the correlation between the methylation status of normal mucosa and characteristics of neoplasia.


METHODS
Paired biopsy specimens of normal mucosa from the proximal and distal colon of 82 patients who underwent colonoscopy were obtained. The methylation status of the promoter region of estrogen receptor 1 (ESR1) and myogenic differentiation 1 (MYOD1) was examined.


RESULTS
Normal mucosa was more highly methylated in the distal than in the proximal colon in both ESR1 and MYOD1 loci (p<0.0001 and p=0.0009, respectively). Advanced characteristics of polyps in the distal colon were frequently observed in patients with lower methylation of ESR1 in the distal colon normal mucosa.


CONCLUSIONS
Methylation levels in normal mucosa differ between the proximal and distal colon, and lower methylation of ESR1 in the distal colon normal mucosa may correlate with advanced features of neoplasia in the distal colon.
Horii
Joichiro
J
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
Hiraoka
Sakiko
S
Kato
Jun
J
Harada
Keita
K
Kuwaki
Kenji
K
Fujita
Hideyuki
H
Toyooka
Shinichi
S
Yamamoto
Kazuhide
K
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D003106:Colon / Q000033:anatomy & histology* / Q000473:pathology; D003111:Colonic Polyps / Q000378:metabolism / Q000473:pathology; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000378:metabolism / Q000473:pathology; D047628:Estrogen Receptor alpha / Q000235:genetics / Q000378:metabolism; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008745:Methylation; D008875:Middle Aged; D017570:MyoD Protein / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D013223:Statistics as Topic
C506487:ESR1 protein, human; D047628:Estrogen Receptor alpha; D017570:MyoD Protein; C057363:MyoD1 myogenic differentiation protein