Acrocentric interconnections and NOR variants in human lymphocytes

Relationship between morphological diversity and AgNORs or cathepsin B expression in colorectal cancers

The biological characteristics associated with the morphological diversity of colorectal cancers were investigated to elucidate the causes of this diversity. We examined the proliferative and infiltrating activity of tumor cells, indicated by the mean number of Ag nucleolar organizer region associated proteins (NORs) per nucleus (MNA) and the immunohistochemical response to cathepsin B(CB), in various morphological types of early and advanced colorectal cancers. We examined 73 colorectal cancers obtained by endoscopic and surgical resection. MNA values for sessile and flat-elevated cancers were greater than the values for pedunculate, subpedunculate, and flat-or-depressed early cancers (sessile, P < 0.05). In advanced cancers invading the muscularis propria, protruding cancers showed significantly higher MNA values than small ulcerative cancers (P < 0.01). CB expression increased significantly with the progression of colorectal cancers (P < 0.01), but was not related to morphological diversity in early and advanced cancers. In both sessile and flat cancers, CB expression was higher in moderately differentiated than in well differentiated adenocarcinomas. These results indicate that, in colorectal cancers, protruding early cancers without stalks and protruding advanced cancers have higher proliferative activity than pedunculate or flat early cancers and small ulcerative advanced cancers, respectively, and that CB expression is not associated with morphological diversity, but with depth of invasion and histological differentiation.

Acrocentric prophasing in bromodeoxyuridine-incorporated chromosomes

Chromosomes that appear to be incompletely condensed [pulverized, prematurely condensed chromosomes (PCCs), prophasing] are known to occur in metaphase spreads of cells from normal individuals and more frequently in cells from individuals with malignant disease or in cells exposed in vitro or in vivo to various agents such as viruses, chemicals, and radiation. In this study involving bromodeoxyuridine (BrdU)-treated lymphocytes, a selective prophasing of acrocentrics appeared to be occurring. The acrocentrics involved were generally in interconnected groups.