EXPRESSION OF AUTOCRINE MOTILITY FACTOR-RECEPTOR IN COLORECTAL-CANCER AS A PREDICTOR FOR DISEASE RECURRENCE

Background. New biologic prognostic factors are needed to guide the treatment of patients with colorectal cancer. The prognostic value of the altered expression of the cell surface glycoprotein gp78, which has been implicated in tumor-cell invasion and metastasis as an autocrine motility factor (AMF) receptor, was evaluated. Methods. The level of expression of AMF receptor gp78 was analyzed immunohistochemically in tumor specimens from 118 patients who had undergone surgery for colorectal cancer. Multivariate analysis was used to determine whether gp78 expression status was correlated with patient prognosis. Results. Among the 118 patients studied, the 5-year survival rate for the 51 patients who had gp78-positive tumors was significantly poorer that that of the 67 patients who had gp78-negative tumors (49.8% vs. 89%). The incidence of gp78 positivity was correlated with tumor progression as reflected by histologic type, depth of invasion, lymph node metastasis, vessel invasion, and tumor stage. Among the 101 patients who underwent curative resection, the difference in disease free survival between patients with gp78-positive tumors and those with gp78-negative tumors was significant. This significant difference remained among patients who had Stage II tumors. Multivariate analysis with the Cox regression model indicated that gp78 positivity was a good predictor of disease recurrence, ranking with extent of tumor invasion (T classification) and lymph node status (N classification). Conclusions. Increased expression of gp78 is correlated with a high incidence of recurrence and, consequently, with decreased survival of patients with colorectal cancer. Expression of gp78 might be of prognostic value in these patients.