Preliminary screening of chemotherapy-resistant genes in esophageal cancer and its clinical significance / 解放军医学杂志

Objective To initially screen the genes associated with chemotherapeutic resistance in esophageal cancer cells, verify the correlation of the genes to the poor prognosis of patients with esophageal cancer, and predict the possible regulatory mechanism of esophageal cancer resistance. Methods The drug sensitivity data of esophageal cancer cell lines were analyzed from GDSC database to screen the cell lines that were relatively sensitive or resistant to both cisplatin and docetaxel. In order to obtain differentially expressed genes, the transcriptome data of the two groups of cell lines were analyzed by the edgeR package according to the following screening criteria: the log2 (fold change) more than –1 or less than1 and P value <0.05. The enrichment cluster analysis of GO biological process was performed in the relatively highly expressed genes of drug-resistant group to identify possible signaling pathways related with drug resistance, and the target genes related to chemotherapeutic resistance were identified based on previous studies. The associations between the expression level of target gene and the clinical pathological features and prognosis of patients were verified in the tissue transcriptome data of esophageal cancer patients. Finally, the proteins interacting with the target gene encoded protein were predicted online using the STRING database, and its possible mechanism of action was analyzed. Results Five cell lines with resistance to both cisplatin and docetaxel and 5 sensitive cell lines were obtained. According to the transcriptome data of the two groups of cell lines, 1097 differentially expressed genes were finally obtained, including 532 highly expressed and 565 low expressed genes in the drug resistant group. The results of GO enrichment analysis for the highly expressed genes indicated that the receptor protein tyrosine kinase pathway was obviously enriched. The expression level of FGR involved in this pathway was significantly correlated with tumor T stage (P=0.021), clinical stage (P=0.007) and prognosis (P=0.0021) of patients with esophageal cancer. In addition, protein interaction analysis indicated that FGR interacted directly or indirectly with multiple proteins, mainly in the form of kinase. Conclusions The receptor protein tyrosine kinase pathway is the most significant signaling pathway associated with chemotherapeutic resistance in esophageal cancer cells. The expression level of FGR in this signaling pathway is significantly correlated with the pathological stage and prognosis of patients with esophageal cancer. FGR may regulate the drug resistance of esophageal cancer cells by phosphorylating downstream target proteins.

Analysis and validation of PI3K/AKT signaling pathway associated with overall survival time of patients with HER2-positive breast cancer / 解放军医学杂志

Objective To analyze and validate the key molecular targets correlated with the overall survival of patients with HER2-positive breast cancer.Methods First,the survival time and transcriptome data of patients with HER2-positive breast cancer in stage Ⅰ / Ⅱ and Ⅲ/Ⅳ were downloaded from the TCGA database.The significantly differential genes between overall survival ＜2 years and ＞8.5 years in stage Ⅰ / Ⅱ were picked out by edgeR package,and the pathways were enriched by KEGG.Similarly,the differential genes between overall survival ＜2 years and ＞7 years in stage Ⅲ/Ⅳ were analyzed.Furthermore,KEGG pathway analysis was performed using the differential genes overlapped by stage Ⅰ /Ⅱ and Ⅲ/Ⅳ.Second,the relationships between the expression levels of key node genes and other genes in enriched pathway and the overall survival of patients with HER2-positive breast cancer were validated by KMplot database.Last,the correlation between the activity of pathway enriched in KEGG and the resistance to anti-HER2 treatment was validated in HER2-positive breast cancer cell line BT474.Results In patients with stage Ⅰ / Ⅱ HER2-positive breast cancer whose overall survival was ＜2 years,PI3K/AKT was the 9th signaling pathway enriched by up-regulated differential genes.In patients with stage Ⅲ/Ⅳ whose overall survival was ＜2 years,PI3K/AKT was the 2nd signaling pathway enriched by up-regulated differential genes.Furthermore,PI3K/AKT was the first signal pathway enriched by the overlapping upregulated genes of patients in stage Ⅰ / Ⅱ and Ⅲ / Ⅳ whose overall survival was ＜2 years.Patients with high expression of PI3K and AKT (key node genes) or CFAP221 and COL4A6 (other genes) of PI3K/AKT pathway had shorter overall survival than those with low expression.PI3K inhibitors could enhance the growth inhibitory effect of HER2 small molecule inhibitor on HER2-positive breast cancer cell line BT474.Conclusions The overexpression of PI3K/AKT pathway is associated with the shorter overall survival in HER2-positive breast cancer patients,and associated with anti-HER2 resistance in HER2-positive breast cancer cell line.

Effects of esophageal cancer cell-derived exosomes on cancer cell migration and invasion and its mechanism research / 解放军医学杂志

Objective To investigate the biological effects of exosomes secreted by KYSE410 cells on migration and invasion of KYSE410,KYSE510,YES2 cells and the possible mechanisms underlying the phenotype change.Methods The exosomes were isolated from the conditional supernatant of esophageal cancer cell line KYSE410 by ultracentrifugation.The morphology of exosomes was observed by transmission electron microscopy (TEM).Western blotting was used to detect the protein markers of exosomes.The uptaken of fluorescence-labeled KYSE410 exosomes by KYSE410,KYSE510 and YES2 was also recorded under confocal microscopy.Migration and invasion ability of the three esophageal carcinoma cell lines and the effects of exosomes from KYSE410 on migration and invasion of KYSE410,KYSE510 and YES2 cells were analyzed by Transwell chamber,respectively.The alteration of Wnt/β-catenin and PI3K/Akt pathway-related proteins were detected by Western blotting.Results The membrane structure of KYSE410 derived exosomes could be observed with its diameter ranged between 30-100nm.The invasion and migration ability of three esophageal cancer cells are KYSE410＞ KYSE510＞ YES2.KYSE410 exosomes promoted the migration and invasion of KYSE410,KYSE510 and YES2 cells.Conclusions Concentrated exosomes derived from the highly migratory and invasive esophageal cancer cell line KYSE410 promoted the migration and invasion potentials of itself and esophageal cancer cell lines KYSE510 and YES2,which possibly exerted the effects by activating Wnt/β-catenin and PI3K/Akt signaling pathways.

Enrichment analysis of Alu elements with different spatial chromatin proximity in the human genome

Transposable elements (TEs) have no longer been totally considered as "junk DNA" for quite a time since the continual discoveries of their multifunctional roles in eukaryote genomes. As one of the most important and abundant TEs that still active in human genome, Alu, a SINE family, has demonstrated its indispensable regulatory functions at sequence level, but its spatial roles are still unclear. Technologies based on 3C (chromosome conformation capture) have revealed the mysterious three-dimensional structure of chromatin, and make it possible to study the distal chromatin interaction in the genome. To find the role TE playing in distal regulation in human genome, we compiled the new released Hi-C data, TE annotation, histone marker annotations, and the genome-wide methylation data to operate correlation analysis, and found that the density of Alu elements showed a strong positive correlation with the level of chromatin interactions (hESC: r = 0.9, P < 2.2 × 10(16); IMR90 fibroblasts: r = 0.94, P < 2.2 × 10(16)) and also have a significant positive correlation with some remote functional DNA elements like enhancers and promoters (Enhancer: hESC: r = 0.997, P = 2.3 × 10(-4); IMR90: r = 0.934, P = 2 × 10(-2); Promoter: hESC: r = 0.995, P = 3.8 × 10(-4); IMR90: r = 0.996, P = 3.2 × 10(-4)). Further investigation involving GC content and methylation status showed the GC content of Alu covered sequences shared a similar pattern with that of the overall sequence, suggesting that Alu elements also function as the GC nucleotide and CpG site provider. In all, our results suggest that the Alu elements may act as an alternative parameter to evaluate the Hi-C data, which is confirmed by the correlation analysis of Alu elements and histone markers. Moreover, the GC-rich Alu sequence can bring high GC content and methylation flexibility to the regions with more distal chromatin contact, regulating the transcription of tissue-specific genes.

Expression of phosphatidylinositol-3 kinase in epithelial ovarian carcinoma / 中华妇产科杂志

Objective To explore the expression and significance of phosphatidylinositol-3 kinase (PI3K)in ovarian cancer,and the effect of combined PI3K inhibitor(LY294002)therapy with cisplatin on epithelial ovarian carcinoma,and to explore if there is a synergistic effect between the two therapies. Methods The expression levels of PI3K p85 subunit proteins and mRNA were evaluated by western blot and RT-PCR in normal ovarian tissue(G1),ovarian benign tumor tissue(G2),ovarian borderline tumor tissue(G3)and ovarian cancer tissue(G4),and the relevant clinical pathological parameters were analyzed.SKOV3 ceils were isolated and cultured by enzymolysis method.SKOV3 cells were treated with culture medium only,LY294002(1,10,30,50,100 ?mol/L),cisplatin(0.33,1.25,2.5,5, 10 ?mol/L),LY294002(50 ?mol/L)+cisplatin(10 ?mol/L)for 2 days,respectively.The effect of LY294002 and cisplatin on the growth of SKOV3 cells was measured by methyl thiazolyl tetrazolium assay. Results There was no positive expression of PI3K p85 subunit proteins in G1 and G2,while the expression was 2/6 in G3,and 85%(33/39)in G4.PI3K p85 subunit mRNA expression levels were 0.178?0.102 in G1,0.643?0.112 in G2,0.847?0.058 in G3,1.689?0.423 in G4;there was a significant difference between G1,G2,G3 and G4(P0.05).Significant differences were noted between protein expression levels in G4(Ⅲ,Ⅳ)and G4(Ⅰ,Ⅱ;P

Main Volatile Components in the Leaves of Sabina chinensis L. Ant. and Sabina chinensis L. Ant. cv. Kaizuca and Their Effects on Bacteria / 环境与健康杂志

Objective To analyze the volatile composition in the leaves of Sabina chinensis L. Ant. and Sabina chinensis L. Ant. cv. Kaizuca and to study their effects on bacteria. Methods GC-MS was employed in the analysis of volatile composition and four kinds of bacteria were used for testing the sterilization and bacteriostasis of the volatile oil. Results The main substance in volatile oil from the two kinds of plants, Sabina chinensis L. Ant. and Sabina chinensis L. Ant. cv. Kaizuca, was bornyl acetate and the percentage was 38.1% and 46.5% respectively. In addition, in the volatile oil from Sabina chinensis L. Ant. contained 24% of phellandrne and 12.4% of p-menth-l-en-4-o1, as for Sabina chinensis L. Ant. cv. Kaizuca, 30.0% of limonene and 7.9% of ?-pinene were contained. The volatile oil from Sabina chinensis L. Ant. had greater effects of bacteriostasis and sterilization on Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli compared with Sabina chinensis L. Ant. cv. Kaizuca. Conclusion Compared with Sabina chinensis L. Ant. cv. Kaizuca, the effects of sterilization and bacteriostasis of volatile oil from Sabina chinensis L. Ant. are much greater and with a larger spectrum of bacteria.