Budget Amount *help |
¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 1995: ¥1,100,000 (Direct Cost: ¥1,100,000)
Fiscal Year 1994: ¥1,100,000 (Direct Cost: ¥1,100,000)
|
Research Abstract |
To elucidate three-dimensional relationships among the tumor gland, basement membrane, and fibrous stroma in the invasive edge of colorectal cancers, we have attempted several techniques to identify types of collagen fibers by using immuno-scanning electron microscopy (immune-SEM) . During the term of project, immuno-gold labeling of the specimens and observation by immune-SEM with both backscattered and secondary electron imaging, and Texas-red labeling of the similarly prepared specimens and observation by confocal laser-scanning microscopy (CLSM) with three-dimensional image reconstruction were performed, where CLSM being performed to estimate the gold-labeled site on immune-SEM. Stromel collagen fibers, identified as type I,tended to form thick bundles and run parallel to the acinar outer surface. Few fibrous connections were noted between the basement membrane of the cancer acinus (or acinus without basement membranes) and the stromal collagen fibers. Type IV collagen fibers, forming the basement membrane of cancer acini, were observed as waving and densely-arranged bundles of fibers but not wide-meshed, being occasionally discontinuous or absent. In contrast, the basement membrane of the normal crypt formed a wide-meshed and continuous lattice of fibers, and numerous fibrous connections with the interstitial cellagen fibers were noted. Conclusions : 1. The basement membrane of the tumor acini may neither provide a firm anchorage to cancer cells nor be suitable for the penetration of substances, in contrast to that of the normal crypt. The theory that it is a newly-deposited structure, rather than the preexisting basement membrane destroyed by tumor cells, might be supported by the present results. 2. Application of immune-SEM in tissue (not cytologic) level may provide a new way for studying the tumor-stromal interface, which, recently, has been studied by so many investigators from different fields of onocology.
|