TENASCIN-C IN SERUM - A QUESTIONABLE TUMOR-MARKER

In normal adult tissue tenascin-C (TN-C) is usually expressed at low l evels. However, it is strongly induced in many tumors as well as in ot her pathological conditions often associated with inflammation, To eva luate the diagnostic significance of TN-C, we established a sensitive sandwich ELISA to determine TN-C levels in serum. Furthermore, we inve stigated the distribution of TN-C variants in serum and found the larg e TN-C isoforms to be predominant. We measured TN-C in sera from 15 he althy persons, 75 tumor patients and 84 patients selected due to their elevated levels of the acute-phase protein C-reactive protein (CRP), which is a very specific marker for infection and inflammation. It was found that sera from cancer patients can have elevated TN-C levels; h owever, the increase was more pronounced in persons with high levels o f CRP, There appeared to be a correlation of TN-C levels with the leve ls of CRP. In view of these facts, the diagnostic value of TN-C levels in serum as a potential tumor marker seems to be questionable, since our data show that TN-C levels can be elevated as a consequence of inf ection and inflammation. (C) 1995 Wiley-Liss, Inc.