Prognostic importance of RASSF2 expression in patients with gastric cancer who had undergone radical gastrectomy.

BACKGROUND: Although Ras-association domain family of gene 2 (RASSF2) has been shown to undergo promoter methylation at high frequency in some cancer types and in brain metastases, its clinical utility as a useful prognostic molecular marker remains unclear in gastric cancer. METHODS: Prognostic significance of RASSF2 expression was retrospectively analysed by immunohistochemically in 105 patients with gastric cancer who underwent curative gastrectomy. RESULTS: Low RASSF2 expression was detected in 58 (55 %) patients, whereas 47 patients (45 %) had high RASSF2 expression. Lymph node involvement, pT stage, TNM stage, vascular invasion, perineural invasion and the presence of recurrence were found to be significantly related to RASSF2 expression levels. Low PRL-3 expression was closely correlated with lymph node metastasis (p = 0.001), advanced pT stage (p = 0.021), advanced TNM stage (p < 0.001), the presence of vascular invasion (p < 0.001), perineural invasion (p = 0.018) and high prevalence of recurrence (p = 0.003) compared with high RASSF2 expression. The median disease-free survival (DFS) time for patients with low RASSF2 expression was significantly worse than that of patients with high RASSF2 expression (10.2 vs. 50.6 months, p < 0.001). In addition, patients with high RASSF2 expression had the higher overall survival (OS) interval compared to patients with low RASSF2 expression (NR vs. 14.9 months, p < 0.001). In the multivariate analysis, the rate of RASSF2 expression levels was an independent prognostic factor, for DFS [p < 0.001, HR 0.12 (0.10-0.88)] and OS [p < 0.001, HR 0.10 (0.04-0.46)], as were pT stage and TNM stage, respectively. CONCLUSIONS: RASSF2 may be an important molecular marker for carcinogenesis, prognosis and progression in gastric cancer, but the potential value of RASSF2 expression as a useful molecular marker in gastric cancer progression should be evaluated, comprehensively. It would be possible to develop treatments targeting RASSF2 and advance new treatment strategies for gastric cancer.

Prognostic significance of ADAM17 expression in patients with gastric cancer who underwent curative gastrectomy.

BACKGROUNDS: A disintegrin and metalloproteinase (ADAM) 17 has been indicated to be an indispensable regulator of cellular events from proliferation to migration. Although prognostic importance of ADAM17 expression has been investigated in several tumours, its clinical utility as a useful prognostic molecular marker remains unclear in gastric cancer. In the current study, we evaluated the expression of ADAM17 and its prognostic significance in gastric cancer patients after curative gastrectomy. METHODS: The prognostic significance of ADAM17 expression was analysed immunohistochemically in 156 patients with gastric cancer who had undergone curative gastrectomy, and the relationship between its expression and clinicopathological factors was also evaluated. RESULTS: High ADAM17 expression was detected in 79 patients (51 %), whereas low expression was found in 77 cases (49 %). There was significant correlation between gender, histology, lymph node metastasis, vascular invasion, the presence of recurrence and high ADAM17 expression. Recurrence in patients with high ADAM17 expression was significantly higher than that for patients with low ADAM17 expression (p = 0.032). The median disease-free survival (DFS) time for patients with tumours with high ADAM17 expression was worse than that of patients with tumours with low ADAM17 expression (16.6 vs. 44.2 months, p = 0.004). In addition, patients with low ADAM17 expression had a higher median overall survival (OS) (49.6 vs. 26.9 months, p = 0.019) compared to those with high ADAM17 expression. Multivariate analysis indicated that the rate of ADAM17 expression was an independent prognostic factor for DFS, in addition to the already known important clinicopathological prognostic indicator. But the prognostic importance of ADAM17 expression could not be proved by multivariate analysis for OS. CONCLUSIONS: The potential value of ADAM17 expression as a useful molecular marker in gastric cancer progression should be evaluated comprehensively; it may predict recurrence and poor prognosis in patients with gastric cancer after curative resection.