Increased angiogenin expression in gastric cancer correlated with cancer progression

Abstract

Purpose: The purpose of this study is to elucidate the expression of angiogenin and its previously undemonstrated clinical significance in gastric cancer (GC). Methods: Angiogenin expression was examined immunohistochemically in 21 GC tissues and 21 corresponding normal gastric tissues. The serum concentration was determined by enzyme-linked immunosorbent assay (ELISA) in GC patients preoperatively (n=48) and postoperatively (n=41), in nonneoplastic patients preoperatively (n=23) and postoperatively (n=19), and in 32 healthy volunteers. The amount of angiogenin in the tissue of 21 GC patients was also determined by ELISA. Results: Angiogenin expression was observed in GC cells as well as in some fundic glandular cells and some inflammatory cells. The mean serum concentration in GC patients (407.8 ± 105.2 ng/ml) was significantly higher than that in the nonneoplastic patients (345.7 ± 58.3 ng/ml; P < 0.003) and in the healthy volunteers (333.0 ± 59.3 ng/ml; P < 0.0002). The mean serum angiogenin concentrations were progressively higher in the order T1+T2 (P < 0.04) < T3+T4 (P < 0.0001) < recurrent GC (P < 0.05) subgroups, in the order node-negative (P < 0.05) < node-positive (P < 0.0002) subgroups, and in the order stage I+II (P < 0.02) < stage III and over (P < 0.0005) subgroups as compared with those in the healthy volunteers. These elevated serum angiogenin concentrations in each subgroup were significantly (P < 0.0003) reduced after cancer resection. The amounts of angiogenin in GC tissues correlated significantly with the serum angiogenin concentration (P < 0.01). Conclusions: These results suggest that angiogenin expression is increased in GC and that the increased serum concentration in GC patients correlates with cancer progression.