title: Expression and clinical significance of Sirt1 in colorectal cancer.
abstract: The objective of the present study was to examine the expression of Silent information regulator 1 (Sirt1) in colorectal cancer and peritumoral normal mucosa tissue, and therefore analyze the role and molecular mechanism of Sirt1 in the pathogenesis of colorectal cancer. Colorectal cancer tissue specimens were employed as the experimental group, and adjacent normal mucosa tissues >5 cm from tumor lesions were used as the control group. The expression of Sirt1 was detected by the immunohistochemical streptavidin peroxidase detection method in paraffin-embedded sections, whilst Sirt1 protein expression was examined by western blot analysis in the fresh tissues. Sirt1 protein was primarily expressed in the nuclei of the tumor cells, and positive staining was brownish-yellow in color. The relative expression quantities of Sirt1 in the peritumoral normal rectal mucosa and rectal carcinoma were 1.15 and 2.62, and the differences between the two groups were statistically significant (P<0.05). The expression level of Sirt1 in colorectal carcinoma was significantly associated with the depth of tumor invasion, differentiation and tumor size (P<0.05). Sirt1 expression was also found to be associated with tumor tissue type, lymph node metastasis, Duke's stage and patient age. These characteristics combined may therefore be used as markers for the early diagnosis of colorectal cancer pathogenesis.
authors.affiliation: Liaoning Provincial University Key Laboratory of Biophysics, College of Medicine, Dalian University, Dalian, Liaoning 116622, P.R. China; Department of Anorectal Surgery, Affiliated Xinhua Hospital of Dalian University, Dalian, Liaoning 116021, P.R. China.
authors.forename: Deng-Feng
authors.initials: DF
authors.lastname: Yu
authors.affiliation: Liaoning Provincial University Key Laboratory of Biophysics, College of Medicine, Dalian University, Dalian, Liaoning 116622, P.R. China; Department of Gynecology and Obstetrics, Affiliated Zhongshan Hospital of Dalian University, Dalian, Liaoning 116001, P.R. China.
authors.forename: Su-Juan
authors.initials: SJ
authors.lastname: Jiang
authors.affiliation: Liaoning Provincial University Key Laboratory of Biophysics, College of Medicine, Dalian University, Dalian, Liaoning 116622, P.R. China.
authors.forename: Zhi-Peng
authors.initials: ZP
authors.lastname: Pan
authors.affiliation: Department of Anorectal Surgery, Affiliated Xinhua Hospital of Dalian University, Dalian, Liaoning 116021, P.R. China.
authors.forename: Wei-Dong
authors.initials: WD
authors.lastname: Cheng
authors.affiliation: Department of Anorectal Surgery, Affiliated Xinhua Hospital of Dalian University, Dalian, Liaoning 116021, P.R. China.
authors.forename: Wen-Jun
authors.initials: WJ
authors.lastname: Zhang
authors.affiliation: Liaoning Provincial University Key Laboratory of Biophysics, College of Medicine, Dalian University, Dalian, Liaoning 116622, P.R. China.
authors.forename: Xiao-Kun
authors.initials: XK
authors.lastname: Yao
authors.affiliation: Department of Dermatology, Yuzhou People's Hospital, Xuchang, Henan 461670, P.R. China.
authors.forename: Yu-Cheng
authors.initials: YC
authors.lastname: Li
authors.affiliation: Liaoning Provincial University Key Laboratory of Biophysics, College of Medicine, Dalian University, Dalian, Liaoning 116622, P.R. China.
authors.forename: Yong-Zhi
authors.initials: YZ
authors.lastname: Lun
keywords: Sirt1; clinical significance; colorectal cancer; expression