Differential distribution of basement membrane type IV collagen α1(IV), α2(IV), α5(IV) and α6(IV) chains in colorectal epithelial tumors
Article first published online: 9 MAY 2002
Volume 52, Issue 3, pages 224–233, March 2002
How to Cite
Hiki, Y., Iyama, K.-i., Tsuruta, J., Egami, H., Kamio, T., Suko, S., Naito, I., Sado, Y., Ninomiya, Y. and Ogawa, M. (2002), Differential distribution of basement membrane type IV collagen α1(IV), α2(IV), α5(IV) and α6(IV) chains in colorectal epithelial tumors. Pathology International, 52: 224–233. doi: 10.1046/j.1440-1827.2002.01341.x
- Issue published online: 9 MAY 2002
- Article first published online: 9 MAY 2002
- Received 23 October 2001. Accepted for publication 28 December 2001.
- basement membrane;
- colorectal cancer;
- monoclonal antibody;
- type IV collagen α chain
In this study, we examined the relationship between the histopathological grade and immunohistochemical localization of six genetically distinct type IV collagen α chains, the major component of basement membrane (BM), in normal and neoplastic colorectal tissues. In the normal colorectal mucosa, α1/α2(IV) and α5/α6(IV) chains were stained in all epithelial BM. However, α3/α4(IV) chains were restrictively immunostained in the BM of the apical surface epithelium. Similar immunostaining profiles for α1/α2(IV) and α5/α6(IV) chains were observed in tubular adenomas with mild/moderate atypia. However, in intramucosal carcinomas, both α1/α2(IV) chains were linearly stained in the BM of cancer cell nests, while the assembly of α5/α6(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 α5/α6(IV), partly α3/α4(IV) chains, in addition to the classic network of α1/α2(IV) chains. The differential immunohistochemical localization of the type IV collagen α5/α6 chains could be one diagnostic marker for the invasiveness of colorectal cancer.