Differential expression of tenascin-C and tenascin-X in human astrocytomas

• DOI: 10.1007/s004010050636
• Publication Date: 2002-08-25T08:36:27Z
• Authors: Koichi Hasegawa; T. Yoshida; Ken-ichi Matsumoto; Koji Katsuta; Shiro Waga; Teruyo Sakakura
• Keywords: 0301 basic medicine; Brain Neoplasms; Immunoblotting; Tenascin; Astrocytoma; Immunohistochemistry; Cell Line; Up-Regulation; Mice; 03 medical and health sciences; Animals; Humans; Cell Division

Tenascins (TNs) are a family of extracellular matrix glycoproteins. The first member of this family to be recognized, tenascin-C (TN-C), is known to be expressed in various tumors including human astrocytomas. Tenascin-X (TN-X) is the latest member of the TN family to be reported, and its expression in tumor tissues has not yet been examined. In this study, we found expression of TN-X in glioma cell lines and human astrocytomas by immunoblot analysis using anti-mouse TN-X antibodies. We also examined the expression of TN-C and TN-X immunohistochemically in a series of 32 human astrocytomas and tissue from 5 normal brains. Expression of TN-X was up-regulated to a higher degree in low-grade astrocytomas than in high-grade astrocytomas. TN-X was mainly localized in the perivascular stroma around tumor vessels, and weakly expressed in the intercellular spaces among tumor cells. In contrast, TN-C was more strongly expressed in the intercellular spaces and in tumor vessels in high-grade astrocytomas (anaplastic astrocytomas and glioblastomas) than in low-grade astrocytomas. In the tissues expressing both TNs, the distribution of TN-X was often reciprocal to that of TN-C. These findings indicate that the expression of TN-C and TN-X in astrocytomas is different, and that these glycoproteins could be involved in neovascularization in different manners.