title: Detection of APC gene deletions in colorectal malignancies using quantitative PCR in a Chinese population.
abstract: The adenomatous polyposis coli (APC) gene has been shown to be involved in genetic instability and to be downregluated in several human carcinomas. The chromosome locus of APC, 5q21-22, is frequently deleted in colorectal cancers (CRCs). The functional impact of such regions needs to be extensively investigated in large amount of clinical samples. Case-matched tissues of CRC and adjacent normal epithelium (n = 134) were included in this study. Quantitative PCR was carried out to examine the copy number as well as mRNA expression of APC gene in colorectal malignancies. Our results showed that copy number deletions of APC were present in a relatively high percentage of colorectal cancer samples (26.1%, 35 out of 134). There was a positive correlation between copy number decrease of APC and tumor progression in CRCs. Furthermore, copy number loss of APC was correlated with decreased mRNA expression. However, mRNA levels of APC were also impaired in CRC samples with unaltered copy numbers, indicating that sporadic CRCs exhibit different mechanisms of APC regulation.
authors.affiliation: Biomedical Research Institute, Shenzhen-PKU-HKUST Medical Center, Shenzhen, People's Republic of China.
authors.forename: Zhengyu
authors.initials: Z
authors.lastname: Fang
authors.forename: Yi
authors.initials: Y
authors.lastname: Xiong
authors.forename: Jiana
authors.initials: J
authors.lastname: Li
authors.forename: Li
authors.initials: L
authors.lastname: Liu
authors.forename: Manhui
authors.initials: M
authors.lastname: Li
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Lei
authors.initials: L
authors.lastname: Shi
authors.forename: Jun
authors.initials: J
authors.lastname: Wan
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology; D002288:Adenocarcinoma, Mucinous / Q000235:genetics* / Q000473:pathology; D025601:Adenomatous Polyposis Coli Protein / Q000235:genetics*; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D056915:DNA Copy Number Variations / Q000235:genetics*; D004273:DNA, Neoplasm / Q000235:genetics; D017353:Gene Deletion; D006801:Humans; D009367:Neoplasm Staging; D011379:Prognosis; D060888:Real-Time Polymerase Chain Reaction
chemical_list: C555337:APC protein, human; D025601:Adenomatous Polyposis Coli Protein; D004273:DNA, Neoplasm