title: Differential distribution of basement membrane type IV collagen alpha1(IV), alpha2(IV), alpha5(IV) and alpha6(IV) chains in colorectal epithelial tumors.
abstract: In this study, we examined the relationship between the histopathological grade and immunohistochemical localization of six genetically distinct type IV collagen alpha chains, the major component of basement membrane (BM), in normal and neoplastic colorectal tissues. In the normal colorectal mucosa, alpha1/alpha2(IV) and alpha5/alpha6(IV) chains were stained in all epithelial BM. However, alpha3/alpha4(IV) chains were restrictively immunostained in the BM of the apical surface epithelium. Similar immunostaining profiles for alpha1/alpha2(IV) and alpha5/alpha6(IV) chains were observed in tubular adenomas with mild/moderate atypia. However, in intramucosal carcinomas, both alpha1/alpha2(IV) chains were linearly stained in the BM of cancer cell nests, while the assembly of alpha5/alpha6(IV) chains into the BM was inhibited in a discontinuous or negatively stained pattern. The normal colorectal mucosa forms a second network of BM composed of alpha5/alpha6(IV), partly alpha3/alpha4(IV) chains, in addition to the classic network of alpha1/alpha2(IV) chains. The differential immunohistochemical localization of the type IV collagen alpha5/alpha6 chains could be one diagnostic marker for the invasiveness of colorectal cancer.
authors.affiliation: Department of Surgical Pathology, Kumamoto University School of Medicine, Kumamoto, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Hiki
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Iyama
authors.forename: Junji
authors.initials: J
authors.lastname: Tsuruta
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Egami
authors.forename: Takihiro
authors.initials: T
authors.lastname: Kamio
authors.forename: Shuji
authors.initials: S
authors.lastname: Suko
authors.forename: Ichiro
authors.initials: I
authors.lastname: Naito
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Sado
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Ninomiya
authors.forename: Michio
authors.initials: M
authors.lastname: Ogawa
mesh_terms: D000236:Adenoma / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D001485:Basement Membrane / Q000378:metabolism* / Q000473:pathology; D002277:Carcinoma / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D024141:Collagen Type IV / Q000145:classification / Q000378:metabolism*; D003106:Colon / Q000033:anatomy & histology / Q000378:metabolism / Q000473:pathology; D015179:Colorectal Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D006801:Humans; D007124:Immunoenzyme Techniques; D009361:Neoplasm Invasiveness; D009378:Neoplasms, Multiple Primary; D012007:Rectum / Q000033:anatomy & histology / Q000378:metabolism / Q000473:pathology
chemical_list: D024141:Collagen Type IV