Department of Pathology, College of Medicine, The Catholic University of Korea, 505 Banpo-dong, Seocho-gu, Seoul 137-701, Korea.
J Cancer Res Clin Oncol. 2012 Apr;138(4):611-9. doi: 10.1007/s00432-011-1140-8. Epub 2012 Jan 3.
The specific aim of this study was to investigate whether the PDCD4 gene is involved in the development and progression of gastric cancer.
We examined the genetic and epigenetic alterations of the PDCD4 gene as well as the expression of PDCD4 protein in gastric cancers. The mRNA expression of PDCD4 and miRNA-21 expression were also analyzed using quantitative real-time RT-PCR.
Loss or reduced PDCD4 expression was observed in 79 (36.7%) of 215 gastric cancer specimens. Statistically, altered PDCD4 expression was not associated with the clinicopathological parameters, including tumor differentiation, location, lymph node metastasis and overall survival (P > 0.05). miRNA-21 overexpression was frequently detected in gastric cancers (31 of 46, 67.4%), and there was a significant inverse correlation between miRNA-21 and PDCD4 protein expression (P = 0.029), but not between miRNA-21 and PDCD4 mRNA expression. In genetic analysis, no mutation was detected in the coding region of the PDCD4 gene, and promoter hypermethylation was found in 24 (36.4%) of the 66 gastric cancer samples.
Our data suggest that overexpression of miRNA-21 and reduced or loss of PDCD4 expression may play a role in the development and progression of gastric cancers.
本研究的具体目的是探讨 PDCD4 基因是否参与胃癌的发生和发展。
我们检测了 PDCD4 基因的遗传和表观遗传改变以及 PDCD4 蛋白在胃癌中的表达。还使用定量实时 RT-PCR 分析了 PDCD4 和 miRNA-21 的 mRNA 表达。
在 215 例胃癌标本中，有 79 例（36.7%）观察到 PDCD4 表达缺失或减少。统计学上，改变的 PDCD4 表达与临床病理参数（包括肿瘤分化、位置、淋巴结转移和总生存）无关（P>0.05）。miRNA-21 在胃癌中频繁被检测到（46 例中的 31 例，67.4%），miRNA-21 与 PDCD4 蛋白表达之间存在显著的负相关（P=0.029），但与 PDCD4 mRNA 表达之间没有相关性。在遗传分析中，PDCD4 基因编码区未检测到突变，在 66 例胃癌样本中有 24 例（36.4%）存在启动子超甲基化。
我们的数据表明，miRNA-21 的过度表达和 PDCD4 表达的减少或缺失可能在胃癌的发生和发展中起作用。
