Differential gene expression profiling of gastric intraepithelial neoplasia and early-stage adenocarcinoma

Figure 1 All of the transcripts that were statistically significant both in gastric early-stage adenocarcinoma vs low-grade intraepithelial neoplasia and high-grade intraepithelial neoplasia vs low-grade intraepithelial neoplasia and were involved in the Gene Ontology enrichment analysis. LGIN: Low-grade intraepithelial neoplasia; EGC: Early-stage adenocarcinoma; HGIN: High-grade intraepithelial neoplasia.

Figure 2 Unsupervised cluster analysis of gastric low-grade intraepithelial neoplasia and early-stage adenocarcinoma (A), low-grade intraepithelial neoplasia and high-grade intraepithelial neoplasia (B) tissue samples with the 289 differentially expressed transcripts. The transverse blue bar indicates the histopathological type of the tissue samples: A: Light blue, low-grade intraepithelial neoplasia (LGIN); Dark blue, early-stage adenocarcinoma (EGC); B: Light blue, LGIN; Dark blue, high-grade intraepithelial neoplasia (HGIN). Each column represents a sample, and each row represents a transcript. The expression abundance from low levels to high levels is shown in colors from blue to red.

Figure 3 G₀S₂ expression is increased in gastric high-grade intraepithelial neoplasia and early-stage adenocarcinoma in the microarray. The G₀S₂ mRNA expression in gastric high-grade intraepithelial neoplasia (HGIN), tissue shows a statistically significant elevation compared with that of low-grade intraepithelial neoplasia (LGIN). No statistically significant difference in G₀S₂ expression was found between HGIN and early-stage adenocarcinoma (EGC). The results are expressed as the mean ± SE.

Figure 4 G₀S₂ expression was validated by quantitative polymerase chain reaction in the independent samples. The results are shown as the mean ± SE. -ΔCTG₀S₂ represents the expression level of G₀S₂. The differences of -ΔCTG₀S₂ in the 4 groups [low-grade intraepithelial neoplasia (LGIN), high-grade intraepithelial neoplasia (HGIN), early-stage adenocarcinoma (EGC) and gastritis] were compared using an analysis of variance (one-way ANOVA). A test for the homogeneity of variances shows P = 0.105, indicating that the variances are equal. The mean difference between LGIN and HGIN was statistically significant (P = 0.004). The mean difference between LGIN and EGC was statistically significant (P < 0.001).

Figure 5 Representative immunohistochemistry for G₀S₂ in gastric samples. Representative samples are shown from G₀S₂ (A) chronic gastritis tissues with negative expression, and G₀S₂ (B) low-grade intraepithelial neoplasia tissues with low expression, G₀S₂ (C) high-grade intraepithelial neoplasia tissues with medium expression, and G₀S₂ (D) early-stage adenocarcinoma tissues with high expression (bar represents 100 μm).