title: Global histone H4 acetylation and HDAC2 expression in colon adenoma and carcinoma.
abstract: Chromatin remodeling and activation of transcription are important aspects of gene regulation, but these often go awry in disease progression, including during colon cancer development. We investigated the status of global histone acetylation (by measuring H3, H4 acetylation of lysine residues, which also occur over large regions of chromatin including coding regions and non-promoter sequences) and expression of histone deacetylase 2 (HDAC2) in colorectal cancer (CRC) tissue microarrays using immunohistochemical staining. Specifically, HDAC2 and the acetylation of histones H4K12 and H3K18 were evaluated in 134 colonic adenomas, 55 moderate to well differentiated carcinomas, and 4 poorly differentiated carcinomas compared to matched normal tissue. In addition, the correlation between expression of these epigenetic biomarkers and various clinicopathological factors including, age, location, and stage of the disease were analyzed. HDAC2 nuclear expression was detected at high levels in 81.9%, 62.1%, and 53.1% of CRC, adenomas, and normal tissue, respectively (P = 0.002). The corresponding nuclear global expression levels in moderate to well differentiated tumors for H4K12 and H3K18 acetylation were increased while these levels were decreased in poorly differentiated tumors (P = 0.02). HDAC2 expression was correlated significantly with progression of adenoma to carcinoma (P = 0.002), with a discriminative power of 0.74, when comparing cancer and non-cancer cases. These results suggest HDAC2 expression is significantly associated with CRC progression.
authors.affiliation: Department of Medicine and Cancer Center, Howard University College of Medicine, Washington, DC, USA. hashktorab@howard.edu
authors.forename: Hassan
authors.initials: H
authors.lastname: Ashktorab
authors.forename: Kevin
authors.initials: K
authors.lastname: Belgrave
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Hosseinkhah
authors.forename: Hassan
authors.initials: H
authors.lastname: Brim
authors.forename: Mehdi
authors.initials: M
authors.lastname: Nouraie
authors.forename: Mikiko
authors.initials: M
authors.lastname: Takkikto
authors.forename: Steve
authors.initials: S
authors.lastname: Hewitt
authors.forename: Edward L
authors.initials: EL
authors.lastname: Lee
authors.forename: R H
authors.initials: RH
authors.lastname: Dashwood
authors.forename: Duane
authors.initials: D
authors.lastname: Smoot
mesh_terms: D000107:Acetylation; D000236:Adenoma / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D014408:Biomarkers, Tumor / Q000032:analysis; D002277:Carcinoma / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D003110:Colonic Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D018450:Disease Progression; D005260:Female; D006655:Histone Deacetylases / Q000032:analysis*; D006657:Histones / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D046228:Microarray Analysis; D008875:Middle Aged
chemical_list: D014408:Biomarkers, Tumor; D006657:Histones; D006655:Histone Deacetylases