title: Expression of mitochondrial genes MT-ND1, MT-ND6, MT-CYB, MT-COI, MT-ATP6, and 12S/MT-RNR1 in colorectal adenopolyps.
abstract: Despite improvements in treatment strategies, colorectal cancer (CRC) still has high mortality rates. Most CRCs develop from adenopolyps via the adenoma-carcinoma sequence. A mechanism for inhibition of this sequence in individuals with a high risk of developing CRC is urgently needed. Differential studies of mitochondrial (mt) gene expressions in the progressive stages of CRC with villous architecture are warranted to reveal early risk assessments and new targets for chemoprevention of the disease. In the present study, reverse transcription-quantitative PCR (RT-qPCR) was used to determine the relative amount of the transcripts of six mt genes [MT-RNR1, MT-ND1, MT-COI, MT-ATP6, MT-ND6, and MT-CYB (region 648-15887)] which are involved in the normal metabolism of mitochondria. A total of 42 pairs of tissue samples obtained from colorectal adenopolyps, adenocarcinomas, and their corresponding adjacent normal tissues were examined. Additionally, electron transport chain (ETC), complexes I (NADH: ubiquinone oxidoreductase) and III (CoQH2-cytochrome C reductase), and carbonyl protein group contents were analyzed. Results indicate that there were differential expressions of the six mt genes and elevated carbonyl protein contents among the colorectal adenopolyps compared to their paired adjacent normal tissues (p < 0.05). The levels of complexes I and III were higher in tumor tissues relative to adjacent normal tissues. Noticeably, the expression of MT-COI was overexpressed in late colorectal carcinomas among all studied transcripts. Our data suggest that increased expressions in certain mt genes and elevated levels of ROS may potentially play a critical role in the colorectal tumors evolving from adenopolyps to malignant lesions.
authors.affiliation: Department of Medicine, Morehouse School of Medicine, 720 Westview Dr. SW, Atlanta, GA, 30310, USA.
authors.forename: LaShanale
authors.initials: L
authors.lastname: Wallace
authors.affiliation: Department of Medicine, Morehouse School of Medicine, 720 Westview Dr. SW, Atlanta, GA, 30310, USA.
authors.forename: Sharifeh
authors.initials: S
authors.lastname: Mehrabi
authors.affiliation: Department of Physiology, Morehouse School of Medicine, 720 Westview Dr. SW, Atlanta, GA, 30310, USA.
authors.forename: Methode
authors.initials: M
authors.lastname: Bacanamwo
authors.affiliation: Department of Physiology, Morehouse School of Medicine, 720 Westview Dr. SW, Atlanta, GA, 30310, USA.
authors.forename: Xuebiao
authors.initials: X
authors.lastname: Yao
authors.affiliation: Department of Medicine, Morehouse School of Medicine, 720 Westview Dr. SW, Atlanta, GA, 30310, USA. faikhionbare@msm.edu.
authors.forename: Felix O
authors.identifier: http://orcid.org/0000-0003-1816-7987
authors.initials: FO
authors.lastname: Aikhionbare
mesh_terms: D000368:Aged; D015179:Colorectal Neoplasms / Q000209:etiology / Q000378:metabolism*; D045303:Cytochromes b / Q000235:genetics; D003576:Electron Transport Complex IV / Q000235:genetics; D005260:Female; D006801:Humans; D008297:Male; D025261:Mitochondrial Proton-Translocating ATPases / Q000235:genetics*; D009245:NADH Dehydrogenase / Q000235:genetics*; D012335:RNA, Ribosomal / Q000235:genetics*; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D045303:Cytochromes b; D003576:Electron Transport Complex IV; D025261:Mitochondrial Proton-Translocating ATPases; D009245:NADH Dehydrogenase; D012335:RNA, Ribosomal; D017382:Reactive Oxygen Species; C501005:MT-ATP6 protein, human; C075526:RNA, ribosomal, 12S; C507225:MT-ND6 protein, human; C515075:NADH dehydrogenase subunit 1, human
keywords: Cancer progression; Carbonyl content; Colorectal tumors; Gene expression; Mitochondria