title: Proliferation kinetics and apoptosis of serrated adenoma of the colorectum.
abstract: To elucidate the proliferation kinetics and cell loss by apoptosis of serrated adenoma (SA) of the colorectum, we performed Ki-67 immunohistochemistry and the terminal deoxynucleotidyl transferase (TdT)-mediated biotinylated deoxyuridine-triphosphate nick-end labeling (TUNEL) method for 24 SA, and compared the results to those of normal colonic mucosa (n = 15), hyperplastic polyp (HP) (n = 18) and traditional tubular adenoma (TA) (n = 55). The growth fraction (Ki-67 labeling index) of SA was 18.8%, which was significantly lower than those of TA (40.1%) and HP (23.8%), while the apoptotic index of SA (0.14%) was significantly lower than that of TA (1.17%). The proliferative compartment in SA was distributed either basally (47%, 60/117 crypts), or in the intermediate portion (51.3%, 55/117 crypts), and there was no superficial translocation of the proliferative compartment, which was seen in 81.2% (361/445 crypts) of TA crypts. These results indicate that SA is a tumor with low proliferative activity and its growth would be maintained by a low extent of cell loss by apoptosis. The results also indicate the neoplastic process in SA is characterized by the disorder of cell migration, maturation and exfoliation similar to HP, and its epithelial cell maturation and migration occasionally occur bidirectionally, toward the surface and to the bottom of the crypt.
authors.affiliation: Division of Molecular and Diagnostic Pathology, Department of Molecular Genetics, Graduate School of Medical and Dental Sciences, Course for Molecular and Cellular Medicine, Niigata University, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Komori
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Ajioka
authors.forename: Hidenobu
authors.initials: H
authors.lastname: Watanabe
authors.forename: Koji
authors.initials: K
authors.lastname: Oda
authors.forename: Yuji
authors.initials: Y
authors.lastname: Nimura
mesh_terms: D000236:Adenoma / Q000378:metabolism / Q000473:pathology*; D017209:Apoptosis; D014408:Biomarkers, Tumor / Q000378:metabolism; D002455:Cell Division; D002465:Cell Movement; D003106:Colon / Q000378:metabolism / Q000473:pathology; D003111:Colonic Polyps / Q000378:metabolism / Q000473:pathology; D015179:Colorectal Neoplasms / Q000378:metabolism / Q000473:pathology*; D004273:DNA, Neoplasm / Q000032:analysis; D006801:Humans; D006965:Hyperplasia / Q000378:metabolism / Q000473:pathology; D007124:Immunoenzyme Techniques; D020287:In Situ Nick-End Labeling; D007413:Intestinal Mucosa / Q000378:metabolism / Q000473:pathology; D019394:Ki-67 Antigen / Q000378:metabolism; D007700:Kinetics
chemical_list: D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; D019394:Ki-67 Antigen