Immunohistochemical localization of cathepsin D in colorectal tumors.
OBJECTIVE
Although it has been suggested that cathepsin D, a lysosomal protease, is involved in tumor invasion and metastasis in human colorectal cancers, conflicting studies have also been reported recently. In addition, this issue has been only rarely studied in human colorectal tumors by use of immunohistochemical methods. The aim of the study presented here was to clarify not only the correlation between cathepsin D expression and tumor invasion or metastasis but also the correlation between the intracellular immunostaining pattern of cathepsin D and tumor invasion and metastasis in human colorectal tumors.


METHODS
Thirty-four primary colorectal adenocarcinomas and 24 adenomas were immunostained by use of an anticathepsin D antibody. Both the incidence and the immunostaining patterns of cathepsin D were investigated in all tissue samples.


RESULTS
Three different immunostaining patterns, i.e., supranuclear, basal, and diffuse, were observed in samples containing cathepsin D. Although the incidence of cathepsin D-positive carcinomas was not correlated with tumor progression, invasion, or metastasis, the immunostaining pattern was significantly correlated with lymphatic invasion.


CONCLUSIONS
The results of this study suggest that abnormal cathepsin D immunostaining patterns (basal or diffuse) can be used to predict a potential for lymphatic invasion in colorectal carcinoma.
Arao
J
J
Second Department of Pathology, Dokkyo University School of Medicine, Tochigi, Japan.
Fukui
H
H
Ono
Y
Y
Ueda
Y
Y
Chiba
T
T
Fujimori
T
T
D000230:Adenocarcinoma / Q000473:pathology*; D018256:Adenomatous Polyps / Q000473:pathology*; D002402:Cathepsin D / Q000378:metabolism*; D003106:Colon / Q000473:pathology; D015179:Colorectal Neoplasms / Q000473:pathology*; D006801:Humans; D007124:Immunoenzyme Techniques; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D012007:Rectum / Q000473:pathology
D002402:Cathepsin D