[Expression of stathmin in esophageal squamous cell carcinoma and its biological significance].
ABSTRACT To explore the expression of stathmin gene in esophageal squamous cell carcinoma (ESCC) and its correlation to oncogenesis of ESCC.
Three ESCC cell lines, 75 ESCC samples, 25 tumor-adjacent samples and 30 normal esophageal mucosa samples were examined for the expression of stathmin mRNA and protein by in situ hybridization and immunohistochemistry, respectively. The correlations of stathmin expression to the clinicopathological features of the patients were analyzed.
Overexpression of stathmin mRNA and protein was found in 3 ESCC cell lines EC9706, Eca109 and EC-1, with the positive expression rates exceeding 80%. The positive rates of stathmin mRNA and protein in ESCC samples were 82.7% and 81.3%, respectively. There were significant differences in the relative contents of stathmin mRNA and protein among normal mucosa tissue, tumor-adjacent tissue and cancer tissue (chi2=19.204 and 25.03, respectively, P<0.01). In addition, a positive correlation was noted between stathmin mRNA and protein expressions in ESCC (r=0.413, P=0.000). The relative contents of stathmin mRNA and protein were significantly correlated to the differentiation degree, lymph node metastasis, invasive depth and TNM stage of ESCC (P<0.05).
The expression of stathmin mRNA and protein is upregulated in ESCC with correlation to the differentiation degree, lymph node metastasis, invasive depth and TNM stage of ESCC, suggesting the possible involvement of stathmin in the oncogenesis of ESCC. Combined detection of stathmin mRNA and protein may prove valuable for early diagnosis and prognosis of ESCC, and stathmin may serve as a potential molecular target for biotherapy of the tumor.
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ABSTRACT: Stathmin1 (STMN1) is a candidate oncoprotein and prognosis marker in several kinds of cancers. This study was aimed to analyze its expression and biological functions in gastric cancer. The expression of STMN1 was evaluated by qRT-PCR, western blot and immunohistochemistry. The biological function of STMN1 was determined by MTT proliferation assays, monolayer colony formation and cell invasion assays using small interference RNA technique in gastric cancer cell lines. We also explored the regulation of STMN1 expression by microRNA-223. STMN1 was upregulated in gastric cancer cell lines and primary gastric adenocarcinomas. STMN1-positive tumors were more likely to be found in old age group and associated with p53 nuclear expression. In diffuse type gastric adenocarcinomas, STMN1 expression was correlated with age (p = 0.043), T stage (p = 0.004) and lymph node metastasis (p = 0.046). Expression of STMN1 in diffuse type gastric adenocarcinoma was associated with poor disease specific survival by univariate analysis (p = 0.01). STMN1 knockdown in AGS and MKN7 cell lines suppressed proliferation (p<0.001), reduced monolayer colony formation (p<0.001), inhibited cell invasion and migration ability (p<0.001) and induced G1 phase arrest. siSTMN1 could also suppress cell growth in vivo (p<0. 01). We finally confirmed that STMN1 is a putative downstream target of miR-223 in gastric cancer. Our findings supported an oncogenic role of STMN1 in gastric cancer. STMN1 might serve as a prognostic marker and a potential therapeutic target for gastric cancer.PLoS ONE 01/2012; 7(3):e33919. · 4.09 Impact Factor