论文部分内容阅读
Background The role of epigenetics in gene expression regulation and development significantly enhances ourunderstanding of carcinogenesis.All the tumor related genes may be the target of epigenetical or genetic regulation.Weselected some epigenetically regulated genes for cDNA array analysis and observed variability in the expression of theDICER1 gene in distinct stages of gastric cancer.The aim of this study was to assess the correlation between theexpression of DICER1,an epigenetically regulated gene,and gastric cancer.Methods To detect the expression of 506 tumor-associated genes,including DICER1,in the matched cancerousmucosa,pre-malignant lesion(adjacent mucosa),non-cancerous gastric mucosa and distant lymphocyte metastaticlesion in 3 cases of gastric cancers using cDNA array.DICER1 mRNA expression and DICER1 protein expression werefurther analyzed by Real-time PCR and Western blot in 32 cases of progressive gastric cancer.DICER1 proteinexpression was also detected in 33 early and 30 progressive gastric cancers by the immunohistochemistry(IHC)method.Results In 3 cases of gastric cancer cDNA array showed dramatically decreased expression of DICER1 inpre-malignant lesion,cancerous mucosa and distant lymphocyte metastatic lesions compared with matchednoncancerous gastric mucosa,pre-malignant lesion and cancerous mucosa.Real-time PCR results showed that theexpression level of DICER1 mRNA in gastric cancer was significantly down-regulated compared to normal gastric tissue(P<0.05).The IHC assay also showed that the expression of DICER1 was significantly decreased in progressive gastriccancer.Among the 63 cases of gastric cancers,13/33 early(39.4%)and 19/30(63.3%)progressive cancers showednegative expression of DICER1(50.8%).The difference in expression of DICER1 between early and progressive gastriccancers was significant(P<0.01).The result of Western blotting showed that DICER1 protein was down-regulatedsignificantly in advanced gastric cancer(P<0.05).Conclusions DICER1 expression is decreased during the progression of gastric cancer,especially in progressivegastric cancers,which indicating DICER1 may play an important role in the development of cancer and the epigeneticalregulation involved.
Background The role of epigenetics in gene expression regulation and development significantly enhances our understanding of carcinogenesis. All the tumor related genes may be the target of epigenetical or genetic regulation. Wasedlected some epigenetically regulated genes for cDNA array analysis and observed variability in the expression of the DICER1 gene in distinct stages of gastric cancer. The AIM of this study was to assess the correlation between the expression of DICER1, an epigenetically regulated gene, and gastric cancer. Methods To detect the expression of 506 tumor-associated genes, including DICER1, in the matched cancerous mucosa , pre-malignant lesion (adjacent mucosa), non-cancerous gastric mucosa and distant lymphocyte metastaticles in 3 cases of gastric cancers using cDNA array. DICER1 mRNA expression and DICER1 protein expression were analyzed by Real-time PCR and Western blot in 32 cases of progressive gastric cancer. DICER1 proteinexpression was also detected in 33 early an d 30 progressive gastric cancers by the immunohistochemistry (IHC) method. Results In 3 cases of gastric cancer cDNA array showed directly decreased expression of DICER1 inpre-malignant lesion, cancerous mucosa and distant lymphocyte metastatic lesions compared with matched noncancerous gastric mucosa, pre-malignant lesion and cancerous mucosa. Real-time PCR results showed that the expression level of DICER1 mRNA in gastric cancer was significantly down-regulated compared to normal gastric tissue (P <0.05). The IHC assay also showed that the expression of DICER1 was significantly less progressive Of the 63 cases of gastric cancers, 13 of 33 early (39.4%) and 19/30 (63.3%) of progressive cancers showed negative expression of DICER1 (50.8%). The difference in expression of DICER1 between early and progressive gastriccancers was significant (P <0.01). The result of Western blotting showed that DICER1 protein was down-regulated significantly in advanced gastric cancer (P <0.05) .ConclusionsDICER1 expression is decreased during the progression of gastric cancer, especially in progressive gastric cancers, which indicating DICER1 may play an important role in the development of cancer and the epigenetical regulation involved.