Diffuse expression of hRFI is correlated with blood vessel invasion in gastric carcinoma

Abstract

Background: hRFI, which has a relatively high homology to XIAP, is preferentially expressed in esophageal and colorectal carcinomas, and is involved in the initial tumor formation in the colorectal adenoma-carcinoma sequence. Furthermore, its diffuse expression is associated with colorectal carcinogenesis. However, hRFI expression in gastric carcinomas has not been evaluated so far. Methods: We performed immunohistochemical staining on 76 gastric carcinoma samples using the antibody to hRFI and also analyzed the correlation between the staining pattern of hRFI and the clinico-pathological characteristics. Results: All of the samples were stained focally (31 cases, 40.8%) or diffusely (45 cases, 59.2%) in the cancerous region. On the contrary, most of the normal gastric region showed no staining, except for a few cases that showed slight immunoreactivity in speckles. Furthermore, the proportion of blood vessel involvement was significantly higher in carcinomas with diffuse hRFI expression (28/45, 62.2%) than in carcinomas with focal expression (7/31, 22.6%) (P < 0.001). Liver metastasis was consistently observed in five cases (11.1%) in diffuse, but only one (3.3%) in focal type during the average follow up period of 5 years. However, the 3-year survival rate did not show significant difference between these different staining patterns of hRFI. Conclusions: These results suggest that the detection of the expression pattern of hRFI in gastric carcinomas can be another useful predictor of liver recurrence, especially when combined with other factors. © 2004 Foundation for Promotion of Cancer Research.