Increased angiogenin expression in gastric cancer correlated with cancer progression.

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.