Objective To study the expression and function of miR-145 in papillary thyroid carcinoma (PTC).Methods PTC tissues and adjacent tissues were collected from 43 cases.Expression of miR-145 in PTC tissues and adjacent tissues was detected with RT-PCR.miR-145 analogue was used to transfect TPC-1cell to upregulate miR-145 expression.Brdu-ELISA method was used to detect the proliferation of TPC-1 cell.Flow cytometry instrument was used to detect the apoptosis and cell cycle of TPC-1 cell.Results RT-PCR test showed that relative expression of miR-145 in thyroid carcinoma tissue was 0.369±0.082,significantly lower than 1.029-±0.365 in tissue adjacent,and the difference was statistically significant (t=3.129,P=0.000).The expression of miR-145 in patients whose biggest tumor size ≥ 1 cm was lower than patients whose biggest tumor size ＜1 cm.Compared with patients with single tumor,the expression of miR-145 in patients with multiple tumor was lower,and the dif ferences were statistically significant (P＜0.05).miR-145 expression was enhanced by miR-145 analogue.Compared with negative control,the proliferative ability of thyroid cancer cell TPC-1 was suppressed significantly,and the difference was statistically significant (P＜0.05).In addition,up-regulation of miR-145 expression could block thyroid cancer TPC-1 in G2/M phase.The apoptosis rate of thyroid cancer cell TPC-1 increased significantly (P＜0.05).Conclusions miR-145 expression is decreased significantly in PTC tissue,and is associated with clinical pathological features.Up-regulation of miR-145 expression can inhibit thyroid cancer cell proliferation,block the cell cycle,and promote apoptosis,miR-145 may play an important role in occurrence and development of thyroid cancer.

Objective To investigate the expression of miR-21 and PDCD4mRNA in colorectal cancer and their correlation with clinicopathological characteristics,to elucidate relationship between PDCD4and miR-21 in vivo.Methods Expression of RNA (including miR-21and PDCD4mRNA) and PDCD4 protein were detected respectively by quantitative real-time reverse transcriptase-PCR and SP immunohistochemical staining in 43 cases of colorectal carcinoma and corresponding normal mucous membrane tissue.Results In colorectal carcinoma,expression of miR-21 was higher than that of the control ( P ＜ 0.05 ),and expression of PDCD4mRNA lower than the control ( P ＜ 0.05 ).Expression of miR21 was associated with lymph node metastasis and clinical stages ( Ⅰ + Ⅱ,Ⅲ + Ⅳ ) ( P ＜ 0.05 ).On the other hand,no significant differences were observed regarding sex,tumor site,size,local invasion,distant metastases,clinical stages( Ⅰ,Ⅱ ) (P ＞ 0.05 ).Expression of PDCD4mRNA was associated with local invasion,clinical stages ( Ⅰ,Ⅱ ) ( P ＜ 0.05 ).While no significant differences were found concerning sex,site,size,lymph node metastasis,distant metastases,clinical stages( Ⅰ + Ⅱ,Ⅲ + Ⅳ ) ( P ＞ 0.05 ).miR21 levels was negatively correlated with PDCD4 expression including nuclear and nuclear and cytoplasmic put together (P ＜ 0.05 ),in contrast to PDCD4mRNA and PDCD4 expression in cytoplasmic ( P ＞ 0.05 ).Conclusions ( 1 ) Abnormal expression of PDCD4 mRNA and miR-21 correlate with prognosis in colorectal cancer.(2) miR-21 suppress translation of PDCD4mRNA by binding to the 3'-untranslated region (3'-UTR)of target PDCD4mRNA.

ObjectiveTo explore the expression of miR-130b and RUNX3mRNA in human gastric carcinoma and the clinical significance. MethodsThe expression of miR-130b and RUNX3mRNA were detected by RT-PCR in 40 cases of gastric carcinoma and corresponding normal mucosa tissue. The expression of RUNX3protein was determined by immunohistochemistry SP method. ResultsThe expression of miR-130b was significantly up-regulated in gastric carcinoma than that in the adjacent normal gastric mucosa tissues (2.18 ± 3.75 ) vs.( 2.59 ± 3.45 ),P ＜ 0.05 ; The expression of RUNX3mRNA in gastric carcinoma tissues was significantly lower than that in adjacent normal gastric mucosa tissues( 8.76 ±2.82) vs.( 7.58 ± 2.87 ),P ＜ 0.05.The expression of miR-130b and RUNX3mRNA were positively correlated with lymph node metastasis and clinical stage ( P ＜ 0.05 ) ; No significant association was found between the expression and age,gender,tumor size,distant metastasis and depth of tumor invasion ( P ＞0.05 ).The expression of miR-130b was negatively correlated with RUNX3 protein expression in nuclei and cytoplasm (P ＜ 0.05 ).ConclusionsAbnormal expression of miR-130b and RUNX3mRNA correlates with prognosis of gastric carcinoma; Decreased RUNX3 protein expression may contribute to tumourigenesis.

Objective To investigate the relationship between p27 gene methylation and pathology of colorectal carcinoma. Methods p27 gene methylation promotor region and p27 protein expression were detected respectively by methylation specificity polymerase chain reaction and immunohistochemical staining SP in 106 cases of colorectal carcinoma and each adjacent normal mucous membrane tissue and 22 cases of colorectal adenoma tissue. Results The positive expression rate of p27 gene methylation was statistically different in colorectal carcinoma tissue compared with normal mucous membrane and colorectal adenoma tissue (P＜0.05). Their positive expression rate were 59.4% (63/106), 18.2% (4/22) and 3.8%(4/106) respectively in colorectal carcinoma tissue,colorectal adenoma and normal mucous membrane tissue (P ＜ 0. 05). p27 gene methylation in poorly differentiated group was significantly higher than that in welldifferentiated group (48.0% vs. 24. 7%, P ＜0. 05), in Dukes-A + B stage group was significantly lower than that in Dukes C + D stage group(20. 0% vs. 41.2%, P ＜ 0. 05 ), and it was higher in lymph nodes metastases group than that in lymph nodes negative group(41.5% vs. 23. 1%, P ＜0. 05), that in positive serosa infiltration group was higher than negative serosa infiltration group(32. 5% vs. 24. 1%, P ＞ 0. 05 ).Conclusions Methylated p27 gene protein expression in colorectal carcinoma was significantly higher than normal mucous membrane and colorectal adenoma tissue. The methylation rate of p27 gene in colorectal carcinoma was significantly associated with tumor differentiation, invasive depth, Dukes stage, lymph node metastasis.

Objective To investigate the relations between p53 and K-ras gene mutation in portal venous blood of gastric carcinoma patients and cancer metastasis. Methods p53 and K-ras gene mutation was detected with PCR-SSCP technology in 62 cases of gastric carcinoma. Results p53 and K-ras mutation rate were 39% and 34% in portal venous blood, but only 8% and 4. 8% in peripheral blood; The rate of gene mutation in p53 and K-ras were 24% and 22% in patient without liver metastasis, 92% and 77% in patient with liver metastasis; The rate of gene mutation in p53 and K-ras in portal venous were 39% and 34% before surgical exploration, but 56% and 63% after exploration. The rate of positive detection of the mutation was significantly (P