title: Apoptosis and its correlation with proliferative activity in rectal cancer.
abstract: OBJECTIVE
  Alterations in the normal control of apoptosis and cell proliferation are important factors in multistep colorectal carcinogenesis. The aim of this study was to determine the frequency of apoptosis and cell proliferation in rectal cancers and to examine their relationship to clinicopathological variables and expression of bcl-2 and p53.
  
  
  METHODS
  Terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) staining and immunohistochemical staining for Ki-67, bcl-2, and p53 were performed on paraffin-embedded tissue samples of 57 rectal cancers.
  
  
  RESULTS
  There was a positive linear correlation between apoptotic index (AI) and proliferative index (PI) (gamma = 0.276, P = 0.038). Both apoptosis and cell proliferation were more frequently found in rectal cancers with lymph node metastasis (P = 0.045 and 0.010, respectively). However, the ratio of AI and PI was not different by nodal status. There was no association between Dukes stage and AI or PI. The frequency of apoptosis was inversely related to the expression of bcl-2, but was not related to the p53 status of rectal cancer. There were no association between cell proliferation and the expression of bcl-2 or p53.
  
  
  CONCLUSIONS
  Our results suggest that the susceptibility to apoptosis in rectal cancer is clearly related to the proliferative activity and high turnover rate of tumor cells may contribute to lymph node metastasis.
authors.affiliation: Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Young-Ho
authors.initials: YH
authors.lastname: Kim
authors.forename: Jun Haeng
authors.initials: JH
authors.lastname: Lee
authors.forename: Hokyung
authors.initials: H
authors.lastname: Chun
authors.forename: Seok-Jin
authors.initials: SJ
authors.lastname: Nam
authors.forename: Woo-Yong
authors.initials: WY
authors.lastname: Lee
authors.forename: Sang Yong
authors.initials: SY
authors.lastname: Song
authors.forename: O Jun
authors.initials: OJ
authors.lastname: Kwon
authors.forename: Jae Geun
authors.initials: JG
authors.lastname: Hyun
authors.forename: In Kyung
authors.initials: IK
authors.lastname: Sung
authors.forename: Hee Jung
authors.initials: HJ
authors.lastname: Son
authors.forename: Poong-Lyul
authors.initials: PL
authors.lastname: Rhee
authors.forename: Jae J
authors.initials: JJ
authors.lastname: Kim
authors.forename: Seung Woon
authors.initials: SW
authors.lastname: Paik
authors.forename: Jong Chul
authors.initials: JC
authors.lastname: Rhee
authors.forename: Kyoo Wan
authors.initials: KW
authors.lastname: Choi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017209:Apoptosis; D002455:Cell Division / Q000502:physiology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D019394:Ki-67 Antigen / Q000032:analysis; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis; D012004:Rectal Neoplasms / Q000737:chemistry / Q000473:pathology*; D016159:Tumor Suppressor Protein p53 / Q000032:analysis
chemical_list: D019394:Ki-67 Antigen; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53