Human gene icb-1 (C1orf38) has been initially cloned by our group from endometrial adenocarcinoma cells. In this study, we examined icb-1 expression in 90 endometrial cancer and normal endometrial tissue specimens. Expression of icb-1 was significantly (about 3.5-fold) higher in endometrial cancer than in normal endometrium (p <.0001). Determination of various molecular markers revealed that only Ki-67 expression differed between both groups in a similarly significant manner. Furthermore, we observed a highly significant positive correlation of icb-1 transcript levels with c-erbB2 (HER2) expression (p <.0001). Our data strongly encourage further studies on the function of icb-1 in endometrial cancer.