EXPRESSION AND PROGNOSTIC-SIGNIFICANCE OF IMMUNOREGULATORY MOLECULES IN ESOPHAGEAL CANCER

Major histocompatibility complex molecules (HLA), the co stimulatory m olecule B7 and the intercellular adhesion molecule I (ICAM-1) are key molecules involved in T cell-mediated immune surveillance. We aimed at assessing the expression pattern of these immunoregulatory molecules on primary esophageal carcinomas and evaluating their prognostic signi ficance, Representative samples of primary tumors were obtained from 5 3 patients who had undergone radical en bloc esophagectomy without res idual tumor. Cryostat sections of these tumors were stained with monoc lonal antibodies (MAbs) directed against either HLA class I, HLA class II, B7 or ICAM-1, The median follow-up was 19 months (range, 6-43), W e found that HLA class I expression was deficient on 27 tumors, while a significant neo-expression of HLA class II, B7 and ICAM-1 (greater t han or equal to 25% positive tumor cells) was observed on 17, 29 and 2 5, tumors, respectively, Kaplan-Meier analyses revealed a significant beneficial influence on relapse-free survival for patients with tumors expressing HLA class I, HLA class II and B7, Cox's regression analyse s demonstrated that co-expression of HLA class I and ICAM-1 was a sign ificant and independent predictor of a reduced risk of developing tumo r recurrence, whereas expression of ICAM-1 on HLA class I negative tum ors was correlated with an increased risk of tumor relapse. (C) 1997 W iley-Liss, Inc.