Increased Expression of S100A6 (Calcyclin), a Calcium-binding Protein of the S100 Family, in Human Colorectal Adenocarcinomas

• Published in: Clinical cancer research 2000-01, Vol.6 (1), p.172-177
• Main Authors: Komatsu, K, Andoh, A, Ishiguro, S, Suzuki, N, Hunai, H, Kobune-Fujiwara, Y, Kameyama, M, Miyoshi, J, Akedo, H, Nakamura, H
• Format: Article
• Language: English
• Subjects: Adenocarcinoma - chemistry; Adenocarcinoma - pathology; Adenocarcinoma - surgery; Adenoma - chemistry; Adenoma - pathology; Biological and medical sciences; Blotting, Western; Cell Cycle Proteins; Colonic Neoplasms - chemistry; Colonic Neoplasms - pathology; Colorectal Neoplasms - chemistry; Colorectal Neoplasms - pathology; Colorectal Neoplasms - surgery; Epidermal Growth Factor - analysis; Female; Gastroenterology. Liver. Pancreas. Abdomen; Humans; Immunohistochemistry; Intestinal Mucosa - chemistry; Intestinal Mucosa - pathology; Male; Medical sciences; Middle Aged; Neoplasm Staging; Rectal Neoplasms - chemistry; Rectal Neoplasms - pathology; S100 Calcium Binding Protein A6; S100 Proteins - analysis; Stomach. Duodenum. Small intestine. Colon. Rectum. Anus; Tumors
• ISSN: 1078-0432; 1557-3265

The expression of S100A6 (also known as Calcyclin/2A9/5B10/PRA) in surgically resected human colorectal adenocarcinomas was examined to investigate whether S100A6 plays a role in the malignancy of human tumor cells. Western blot analysis using the lysates from colorectal adenocarcinomas and adjacent normal mucosa from 10 patients revealed that the average S100A6 level of adenocarcinomas was significantly higher (about 2.4-fold) than that of normal mucosa. Immunohistochemical analysis using formalin-fixed paraffin-embedded surgical specimens and monoclonal anti-S100A6 antibody (mAbA6) demonstrated that 2 (5%) of 42 normal mucosa and 6 (46%) of 13 adenoma specimens were mAbA6-positive and showed granular staining localized at the supranuclear regions of epithelial cells, whereas 23 (55%) of 42 adenocarcinomas and 13 (100%) of 13 carcinoma cells that metastasized to the liver were mAbA6-positive and showed diffuse cytoplasmic staining. A significant correlation between S100A6 expression and Dukes’ tumor stage or lymphatic permeation but not with other clinicopathological factors was shown. S100A6 was stained more intensely in peripheral portions than in central portions of adenocarcinomas, whereas Ki-67 (a growth marker) was stained equally in these two portions. These results suggest that S100A6 may be involved in the progression and invasive process of human colorectal adenocarcinomas.