Effects of silencing PRMT6 gene on proliferation and migration of gastric cancer cells / 国际肿瘤学杂志

Objective:To study the effects of silencing protein arginine methyltransferase 6 (PRMT6) gene on cell proliferation and migration of gastric cancer cell line MGC-803, and explore its related molecular mechanism.Methods:The expression levels of PRMT6 mRNA and protein in human normal gastric mucosa epithelial cell line GES-1 and human gastric cancer cell lines (AGS, SGC-7901, MGC-803) were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting. The gastric cancer cell line MGC-803 was divided into silencing control group (NC group), PRMT6 silencing group (si-PRMT6 group), nuclear factor-κB (NF-κB/p65) overexpression group (pcDNA-p65 group), si-PRMT6+ pcDNA-p65 group and PRMT6 silencing and matrix metalloproteinase 9 (MMP9) overexpression group (si-PRMT6+ pcDNA-MMP9 group). Western blotting was used to detect the protein expression levels of PRMT6, NF-κB/p65 and MMP9. CCK-8 kit and Transwell assay were used to measure cell proliferation and migration rates.Results:The results of qRT-PCR showed that the relative expression levels of PRMT6 mRNA in GSE-1, AGS, SGC-7901 and MGC-803 cells were 1.041±0.114, 2.141±0.132, 2.716±0.231, 2.825±0.300, and the difference among the four groups was statistically significant ( F=46.082, P<0.001). Compared with GSE-1 cells, PRMT6 mRNA expression levels were significantly increased in AGS, SGC-7901 and MGC-803 cells (all P<0.001). Western blotting results showed that the relative expression levels of PRMT6 protein in GSE-1, AGS, SGC-7901 and MGC-803 cells were 1.090±0.101, 2.847±0.331, 2.925±0.419 and 3.278±0.463, with a statistically significant difference ( F=22.683, P<0.001). Compared with GSE-1 cells, PRMT6 protein expression levels were significantly increased in AGS, SGC-7901 and MGC-803 cells, with statistically significant differences ( P=0.008; P=0.002; P=0.003). After 48 hours of silencing PRMT6 in MGC-803 cells, in NC group and si-PRMT6 group, the PRMT6 mRNA expression levels were 0.921±0.110 and 0.303±0.045, the PRMT6 protein expression levels were 1.032±0.105 and 0.289±0.043, the cell proliferation activities were 0.917±0.089 and 0.660±0.069, the cell migration rates were (89.122±5.109)% and (30.831±4.463)%, and the p-p65/p65 protein relative expression ratios were 0.947±0.143 and 0.285±0.023. The relative expression levels of PRMT6 mRNA and protein, cell proliferation activity, cell migration rate, protein relative expression ratio of p-p65/p65 in si-PRMT6 group were significantly lower than those in NC group, with statistically significant differences ( t=9.006, P<0.001; t=11.338, P<0.001; t=3.954, P=0.017; t=14.881, P<0.001; t=7.919, P<0.001). Western blotting results showed that the MMP9 protein relative expression levels in NC group, si-PRMT6 group, pcDNA-p65 group and si-PRMT6+ pcDNA-p65 group were 1.202±0.138, 0.318±0.018, 2.849±0.217 and 1.595±0.194, with a statistically significant difference ( F=127.410, P<0.001). Further pairwise comparison showed that the protein relative expression level of MMP9 in si-PRMT6 group was significantly lower than that in NC group ( P<0.001), while that in si-PRMT6+ pcDNA-p65 group was significantly lower than that in pcDNA-p65 group ( P=0.002). Then, MGC-803 cells were co-transfected with si-PRMT6 and pcDNA-p65 or pcDNA-MMP9 for 48 h. The cell proliferation activities in NC group, si-PRMT6 group, si-PRMT6+ pcDNA-p65 group and si-PRMT6+ pcDNA-MMP9 group were 0.923±0.054, 0.608±0.024, 0.818±0.035 and 0.807±0.029, with a statistically significant difference ( F=37.343, P<0.001). Further pairwise comparison showed that the cell proliferation activity of si-PRMT6+ pcDNA-p65 group or si-PRMT6+ pcDNA-MMP9 group was significantly higher than that of si-PRMT6 group (both P<0.001). The cell migration rates of above four groups were (85.195±3.176)%, (28.419±1.845)%, (60.490±7.231)% and (53.653±6.761)%, with a statistically significant difference ( F=59.672, P<0.001). Further pairwise comparison showed that the cell migration rate of si-PRMT6+ pcDNA-p65 group or si-PRMT6+ pcDNA-MMP9 group was significantly higher than that of si-PRMT6 group ( P=0.002; P=0.003). Conclusion:PRMT6 silencing can inhibit the proliferation and migration of gastric cancer cells MGC-803 via deactivation of NF-κB/MMP9 signaling pathway.

Study on the relationship between traditional bullying, cyberbullying and depression in adolescents / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the relationship between traditional bullying, cyberbullying and depression in adolescents, with the involvement frequency and different roles considered.</p><p><b>METHODS</b>A stratified cluster sampling method was used to randomly select 5 726 middle school students in three cities of Anhui province in December 2013. Those students were surveyed by self-designed questionnaire of adolescent health-related behaviors in Anhui province. Self-reports on the general demographic information, physical, verbal, relational bullying and cyberbullying involvement and depression were collected. Additionally, the items assessing depression were based on Self-rating Depression Scale (SDS). The chi-square test used to compare prevalent rates of bullying involvement and depression in different groups of students with different demographic features. Multinomial logistic regressions were performed to explore the relationships between all four types of bullying and depression, after controlling confounders.</p><p><b>RESULTS</b>We got a final effective sample of 5 726 student. The response rate was 99.4% in this study. Among 5 726 adolescents, the prevalence rates of bullying in the last two months were 23.4% (1 339/5 726) physically, 55.0% (3 147/5 726) verbally, 34.2% (1 958/5 726) socially, and 8.9% (512/5 726) electronically. The prevalence rate of depression was 64.8% (3 711/5 726). The detection rate was higher in participants who involved in physical, verbal, relational, and cyber bullying than those who not involved in bullying. After controlling the confounding factors, the different frequency and role of verbal and relational bullying were risk factors of depression (OR = 1.42-3.71, all P values < 0.001). As for physical bullying, except for occasional bully-victims (OR = 1.08, 95% CI: 0.79-1.49), others were more likely to be depressed than noninvolved students. (OR = 1.40-7.84, all P values < 0.001). Frequent involvement in cyberbullying as bullies and (or) victims were more likely to be depressed than noninvolved students (OR = 2.30-4.55, all P values < 0.001), but occasional involvement in cyberbullying as bullies and (or) victims were not the risk factors of adolescents' depression (OR = 1.39, 95% CI:0.97-1.99; OR = 1.58, 95% CI: 0.88-2.82; OR = 1.50, 95% CI:0.82-2.74).</p><p><b>CONCLUSION</b>Involvement in physical, verbal, relational, and cyberbullying were risk factors for depression among adolescent students.</p>

Relationship of development between third molar and second molar, canine in aged 11 / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To analyze the imaging manifestations of third molar (M3) in aged 11, and to explore the relationship of development between M3 and second molar (M2), canine (C).</p><p><b>METHODS</b>A total of 399 cases, aged 11, of West China School of Stomatology in June-August 2010 were selected as the imaging database. The M3, M2, C on the panoramic images were observed and the development degree in 399 was divided. And then the correlation analysis was done.</p><p><b>RESULTS</b>45.5% of M3 in aged 11 was in stage C. 30.8% of M2 was in stage F. 36.1% of C was in stage G. The development of M3 appeared earlier in girls than in boys, and earlier in the mandible than in the maxillary. There was no significant difference between the left and right side. The correlation coefficient between M3 and M2 was 0.437, and the correlation coefficient between M3 and C was 0.132.</p><p><b>CONCLUSION</b>The general trends of the developments of M3 and M2, C were the same. The development of M3 can be used to describe the development of M2 and C, according to the close relationship in radiograph.</p>

The analysis of prognostic factors in treating variceal hemorrhage of liver cirrhosis and portal hypertension with transjugular intrahepatic portosystemic shunt / 中华消化杂志

Objective To analyze the prognostic factors in treating variceal hemorrhage patients of liver cirrhosis and portal hypertension with transjugular intrahepatic portosystemic shunt (TIPS).Methods From January 2003 to December 2008, the data of 162 variceal hemorrhage patients with liver cirrhosis and portal hypertension treated with TIPS was collected, which included basic information, biochemical examination results within 7 days before the operation, regular follow-up observation after the surgery and survival data. The survival prognostic indexes were assessed with Cox regression model. Results The successful rate of TIPS was 99% (161/162). The median follow up duration was 21 months. Child-Pugh score and blood platelet count (PLT) were closely correlated with survival (P = 0. 003 and 0. 024). The total cumulative survival rate in patients with Child-Pugh score below nine (75%, 102/136) was higher than over nine (50%, 13/26) (χ2 = 9. 12,P=0. 003).The total cumulative survival rate of patients with PLT count over 47 ×109/L (74%, 82/112) was higher than below 47 × 109/L(66 %, 33/50, χ2 =4. 528, P = 0. 033). The one year after operation cumulative survival rate of liver function Child-Pugh class A, B, and C was 92%, 85%, 55% respectively. Conclusion Child-Pugh score and platelet count are independent predictable factors for the survival of variceal hemorrhage patients with liver cirrhosis and portal hypertension treated by TIPS. The risk increase after operation when Child-Pugh score over 9 and/or PLT count less 47×109 /L.