title: Differential expression of miRNAs in colon cancer between African and Caucasian Americans: implications for cancer racial health disparities.
abstract: Colorectal cancer (CRC) incidence and mortality are higher in African Americans (AAs) than in Caucasian Americans (CAs) and microRNAs (miRNAs) have been found to be dysregulated in colonic and other neoplasias. The aim of this exploratory study was to identify candidate miRNAs that could contribute to potential biological differences between AA and CA colon cancers. Total RNA was isolated from tumor and paired adjacent normal colon tissue from 30 AA and 31 CA colon cancer patients archived at Stony Brook University (SBU) and Washington University (WU)‑St. Louis Medical Center. miRNA profiles were determined by probing human genome-wide miRNA arrays with RNA isolated from each sample. Using repeated measures analysis of variance (RANOVA), miRNAs were selected that exhibited significant (p<0.05) interactions between race and tumor or significant (fold change >1.5, p<0.05) main effects of race and/or tumor. Quantitative polymerase chain reaction (q-PCR) was used to confirm miRNAs identified by microarray analysis. Candidate miRNA targets were analyzed using immunohistochemistry. RANOVA results indicated that miR-182, miR152, miR-204, miR-222 and miR-202 exhibited significant race and tumor main effects. Of these miRNAs, q-PCR analysis confirmed that miR-182 was upregulated in AA vs. CA tumors and exhibited significant race:tumor interaction. Immunohistochemical analysis revealed that the levels of FOXO1 and FOXO3A, two potential miR-182 targets, are reduced in AA tumors. miRNAs may play a role in the differences between AA and CA colon cancer. Specifically, differences in miRNA expression levels of miR-182 may contribute to decreased survival in AA colon cancer patients.
authors.affiliation: Division of Gastroenterology, Stony Brook University, Stony Brook, NY 11794-8160, USA.
authors.forename: Ellen
authors.initials: E
authors.lastname: Li
authors.affiliation: Division of Cancer Prevention, Stony Brook University, Stony Brook, NY 11794-8160, USA.
authors.forename: Ping
authors.initials: P
authors.lastname: Ji
authors.affiliation: Division of Cancer Prevention, Stony Brook University, Stony Brook, NY 11794-8160, USA.
authors.forename: Nengtai
authors.initials: N
authors.lastname: Ouyang
authors.affiliation: Department of Applied Mathematics and Statistics, Stony Brook University, Stony Brook, NY 11794-8160, USA.
authors.forename: Yuanhao
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Division of Cancer Prevention, Stony Brook University, Stony Brook, NY 11794-8160, USA.
authors.forename: Xin Yu
authors.initials: XY
authors.lastname: Wang
authors.affiliation: Division of Gastroenterology, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors.forename: Deborah C
authors.initials: DC
authors.lastname: Rubin
authors.affiliation: Division of Gastroenterology, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors.forename: Nicholas O
authors.initials: NO
authors.lastname: Davidson
authors.affiliation: Division of Colon and Rectal Surgery, Stony Brook University, Stony Brook, NY 11794-8160, USA.
authors.forename: Roberto
authors.initials: R
authors.lastname: Bergamaschi
authors.affiliation: Department of Pathology, Stony Brook University, Stony Brook, NY 11794-8160, USA.
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: Shroyer
authors.affiliation: Department of Pathology, Stony Brook University, Stony Brook, NY 11794-8160, USA.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Burke
authors.affiliation: Department of Applied Mathematics and Statistics, Stony Brook University, Stony Brook, NY 11794-8160, USA.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhu
authors.affiliation: Division of Cancer Prevention, Stony Brook University, Stony Brook, NY 11794-8160, USA.
authors.forename: Jennie L
authors.initials: JL
authors.lastname: Williams
mesh_terms: D000328:Adult; D001741:Black or African American / Q000235:genetics; D000368:Aged; D003110:Colonic Neoplasms / Q000208:ethnology* / Q000235:genetics* / Q000401:mortality; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged; D020411:Oligonucleotide Array Sequence Analysis; D060888:Real-Time Polymerase Chain Reaction; D044465:White People / Q000235:genetics
chemical_list: D035683:MicroRNAs; C538984:Mirn182 microRNA, human