MiR-30c-5p suppresses migration, invasion and epithelial to mesenchymal transition of gastric cancer via targeting MTA1.

BACKGROUND: In China, gastric cancer (GC) is an ordinary malignant tumor. Recent literatures have shown that microRNA is critical during tumorigenesis. This study focuses on the influence of miR-30c-5p on the metastasis of GC and further explores its underlying mechanism. METHODS: Before the study, expression level of miR-30c-5p and targeted protein was detected in 40 GC tissue samples and 5 GC cells by RT-qPCR. Meanwhile, correlation analysis was conducted between miR-30c-5p expression level and clinicopathological features. In addition, wound healing assay and cell invasion assay were utilized to identify whether miR-30c-5p could affect the migrated and invaded ability of GC cells. Western blotting assay and luciferase assay were used to explore the potential mechanism. RESULTS: In GC tissues, miR-30c-5p expression level was significantly lower and was remarkably related with clinical features such as tumor node metastasis(TNM) stage and lymphatic metastasis. Moreover, the migrated and invaded ability of GC cells was enhanced through knockdown of miR-30c-5p, while overexpression of miR-30c-5p presented with reversed effect. Further study showed that miR-30c-5p inhibited the expression of its target spot, metastasis-associated protein 1(MTA1), and then suppressed the process of epithelial to mesenchymal transition(EMT) which was important in the metastasis of GC. CONCLUSION: The results indicate that miR-30c-5p, a novel suppressor in tumorigenesis, could inhibit the metastasis and EMT via MTA1, which may offer a possible therapeutic target in GC.

[Epidemiological study on status of Helicobacter pylori in children and teenagers in Wuwei city, Gansu province].

OBJECTIVE: To investigate the prevalence of Helicobacter pylori (Hp) infection among children aged 3 to 18 years old of Wuwei city, Gansu province. METHODS: The study was based upon a personal questionnaire and a determination of Hp antigen using the Hp stool antigen test (HpSA) method. A total of 938 subjects and 96 families were selected in Wuwei city. Eighty children and teenagers with a definite positive Hp stool antigen test were examined by serum Western blotting method. RESULTS: The prevalence of Hp was 72.3% (678/938) with no age difference. Prevalence of Hp infection was correlated with type of dwelling, occupation of parents, drinking water source, kindergarten attendance, consumption of raw vegetables, a poor oral hygiene and breast feeding etc. According to the multivariate analysis, drinking water source, kindergarten attendance and consumption of raw vegetables were most strongly associated with prevalence of Hp in children and adolescents. The infection rate of parents whose children were infected with Hp was higher than that of those whose children were not infected [82.3% (121/147) vs 47.4% (18/38), chi(2) = 19.736, P < 0.05]. The antibody responses of 57 samples (71.3%) from 80 children were of type I Hp and 23 samples (28.7%) type II. CONCLUSIONS: Hp infective rate is high in Wuwei city. The data support maternal-child and sibling-sibling transmission as the primary transmission routes of Hp. The results of serological analysis confirm that the majority of Wuwei Hp infection is of type I.

[Expression of cyclooxygenase-2 and urokinase plasminogen activator in gastric carcinoma and the clinical significance thereof].

OBJECTIVE: To investigate expression of cyclooxygenase-2 (COX-2) and urokinase plasminogen activator (uPA) in gastric carcinoma and the clinical significance thereof. METHODS: Strepavidin-peroxidase method was used to detect the expression of COX-2 and uPA in 192 specimens of gastric carcinoma, 56 specimens of paracancer tissues obtained during operation. Immunohistochemical double staining was used to detect the microvessel density (MVD) and microlymphatic density (MLD). Thirty specimens of normal gastric mucosa obtained during gastroscopy were used as controls. RESULTS: The positive rates of COX-2 in the gastric carcinoma and paracancer tissues were 67.7% and 62.5% respectively, both significantly higher than that of the control group (40.0%, both P < 0.05). The positive expression of COX-2 in gastric carcinoma was significantly related with the depth of invasion and MVD (both P < 0.05). The positive rates of uPA in the gastric carcinoma, paracancer tissue were 78.1% and 44.6% respectively, both significantly higher than that of the control tissues (6.7%, both P < 0.01) and there was a significant difference in the positive rates of uPA between the first 2 groups too (P < 0.01). The positive expression of uPA in gastric carcinoma was significantly related with lymph node metastasis, depth of invasion, Lauren typing, differentiation, MVD, and MLD (P < 0.05, P < 0.01). COX-2 expression was positively linked with uPA expression (r = 0.167, P = 0.021). The survival time of the uPA positive group was (38 +/- 4) months, significantly shorter than that of the negative group [(54 +/- 6) months, P < 0.05]. The survival time of the group positive in both COX-2 and uPA was (27 +/- 3) months, significantly shorter than that of the single positive or double negative groups [both (58 +/- 4) months, both P < 0.01). CONCLUSION: COX-2 and uPA are highly expressed in gastric carcinoma. COX-2 expression is positively linked with uPA expression. COX-2 and uPA in the gastric carcinoma participate in the development of gastric cancer in the early process. uPA is significantly related with the survival time.