Objective. To investigate the expression of glutathione peroxidase 2 (GPX2) in human lung adenocarcinoma tissues and its effect on the biological function of lung adenocarcinoma A549 cells. Methods. The expression of GPX2 in lung adenocarcinoma and its effect on survival were analyzed by the TCGA database and the GEPIA 2 database. A total of 45 cases of primary lung adenocarcinoma tissue specimens and 45 cases of their paracancerous tissue specimens were collected, and the expression of GPX2 in the two types of tissues was detected by immunohistochemistry. Lung adenocarcinoma A549 cells were divided into the GPX2 overexpression group (GPX2), the GPX2 knockdown group (si-GPX2), the empty vector group (Vector), the siRNA negative control group (si-NC), and the WT group; the mRNA level and protein expression of GPX2 in each group of A549 cells were detected by real-time fluorescence quantitative PCR and Western blotting; the proliferation activity of each group of cells was detected by the CCK-8 assay; the effect of GPX2 on cell migration and invasion ability was detected by the scratch assay and the Transwell invasion assay; the apoptosis of each group of cells was detected by flow cytometry; Western blotting was performed to detect the expression levels of Bax, Bcl-2, E-cadherin, vimentin, and MMP2 and MMP9 proteins in each group of cells. Results. Bioinformatics analysis showed that the expression of GPX2 was strongly correlated with the prognosis of lung adenocarcinoma patients ( P < 0.01 ). The positive expression rates of GPX2 in lung adenocarcinoma and its paracancerous tissues were 66.0% and 15.7%, respectively ( P < 0.05 ). The results of RT-qPCR and Western blotting showed that the expression level of GPX2 mRNA and protein in A549 cells in the GPX2 group increased, which was significantly higher than that in the WT group ( P < 0.05 ); the expression levels of GPX2 mRNA and protein in A549 cells in the si-GPX2 group were the same, that is, significantly lower than the WT group ( P < 0.05 ). GPX2 overexpression promoted the proliferation, migration, and invasion of A549 cells and inhibited their apoptosis; the results in the si-GPX2 group were opposite to those in the GPX2 group. Compared with the WT group, the expression of Bcl-2, vimentin, and MMP2 and MMP9 protein in the GPX2 group increased ( P < 0.05 ), while the expression of Bax and E-cadherin protein decreased in the GPX2 group ( P < 0.05 ); the results in the si-GPX2 group were opposite to those in the GPX2 group. Conclusion. The expression of GPX2 in lung adenocarcinoma is related to the prognosis of patients. It is proved that GPX2 can promote the migration and invasion of lung adenocarcinoma cells and is related to the EMT/β-catenin pathway. Thus, GPX2 is expected to be an important target for the diagnosis and treatment of lung adenocarcinoma.

Objective: To investigate the effect of RNAi-mediated survivin and Hypoxia-inducible factor 1α (HIF-1α) gene silencing on proliferation and apoptosis of gastric cancer BGC-823 cells.Methods: Small interfering RNAs (siRNAs) targeting survivin and HIF1α mRNAs were designed and synthesized, respectively, while scrambled siRNAs (SCRs) were synthesized. The hypoxia sensitive gastric cancer line BGC-823 was identi ed and transfected by Hifectin II in vitro under hypoxia condition. The cells transfected with siRNA-survivin, siRNA-HIF-1α and SCR were named as sis group, siH group and SCR group, respectively.The expression of survivin and HIF-1α were assessed by RT-PCR and Western blotting assay respectively. Cell apoptosis were determined by ow cytometry. Cell proliferation was measured by MTT assay. The abilities of invasion and migration were evaluated by transwell assays and wound healing assays respectively.Results: The HIF-1α expression of BGC-823 cells increased apparently under hypoxia condition. The survivin targeting siRNA transfection decreased the expression of survivin under hypoxia condition, the combined transfection of survivin targeting siRNA and HIF-1α targeting siRNA down-regulated both the expression of survivin and HIF-1α obviously. Compared with the blank control group, the combined siRNA transfection group displayed obvious features with decreased invasion and migration ability under hypoxia, the apoptosis rate increased and the cell proliferation decreased obviously. Conclusion:The down-regulation of survivin and HIF-1α in BGC-823 cell lines may induce an anticancer effect by enhancing cell apoptosis, and decrease the proliferation, migration and invasion ability.

Objective: To investigate the effect of RNAi-mediated survivin and Hypoxia-inducible factor 1α (HIF-1α) gene silencing on proliferation and apoptosis of gastric cancer BGC-823 cells. Methods: Small interfering RNAs (siRNAs) targeting survivin and HIF1α mRNAs were designed and synthesized, respectively, while scrambled siRNAs (SCRs) were synthesized. The hypoxia sensitive gastric cancer line BGC-823 was identified and transfected by Hifectin II in vitro under hypoxia condition. The cells transfected with siRNA-survivin, siRNA-HIF-1α and SCR were named as sis group, siH group and SCR group, respectively.The expression of survivin and HIF-1α were assessed by RT-PCR and Western blotting assay respectively. Cell apoptosis were determined by flow cytometry. Cell proliferation was measured by MTT assay. The abilities of invasion and migration were evaluated by transwell assays and wound healing assays respectively. Results: The HIF-1α expression of BGC-823 cells increased apparently under hypoxia condition. The survivin targeting siRNA transfection decreased the expression of survivin under hypoxia condition, the combined transfection of survivin targeting siRNA and HIF-1α targeting siRNA down-regulated both the expression of survivin and HIF-1α obviously. Compared with the blank control group, the combined siRNA transfection group displayed obvious features with decreased invasion and migration ability under hypoxia, the apoptosis rate increased and the cell proliferation decreased obviously. Conclusion: The down-regulation of survivin and HIF-1α in BGC-823 cell lines may induce an anticancer effect by enhancing cell apoptosis, and decrease the proliferation, migration and invasion ability.

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Objective The present study was undertaken to investigate the genetic diversity of Rumex patientia L. in distinct habitat types. Methods Eighty samples from 4 natural populations in Jilin Province of China were analyzed by inter-simple sequence repeats (ISSR). Results ISSR techniques produced 135 bands and 71 polymorphic bands, of which the polymorphic bands (PPB) accounted for 52.6% among natural populations; the gene diversity (H) was 0.1751, and Shannon's diversity index (I) was 0.2634. In the population, the percentage of polymorphic loci (P) was 25.93% and 37.04%, the genetic diversity index (H) was 0.0714–0.1124 and Shannon’s diversity index (I) was 0.1121–0.1676. Population E had the highest genetic diversity, however, population S had the lowest. Based on the species genetic differentiation analysis, the total Nei diversity index (Ht) of Rumex patientia L. from Jilin City was 0.1110 and the within-population genetic diversity (Hs) was 0.1751. The coefficient of genetic differentiation between population areas (GST) was 0.3662. The Gene flow between populations was 0.8654. Conclusion The results showed that the inter-population variation accounted for 36.62% of the total variation, and the intra-population variation accounted for 63.38%. Cluster analysis based on Nei’s genetic distance showed that the greatest genetic distance between E and S (0.1218) and the closest genetic distance between W and N (0.0794).