Screening of Molecular Markers of Cisplatin Resistance in Lung Adenocarcinoma and Functional Verification Based on TCGA Database / 肿瘤防治研究

Objective To explore the related genes that play a key regulatory role in cisplatin resistance in lung adenocarcinoma. Methods Bioinformatics methods were used to download the differentially-expressed genes between cisplatin sensitive group and drug resistant group in patients with lung adenocarcinoma in TCGA database and GDSC database. GO function analysis and KEGG pathway enrichment analysis were carried out to analyze the differentially-expressed genes. The protein-protein interaction network was constructed and hierarchical cluster analysis was carried out to screen the key genes. The key genes were verified at the cell level by real-time fluorescence quantitative PCR and ELISA. Then the expression of the selected key gene in A549/DDP cells was silenced by siRNA and its sensitivity to cisplatin was detected. Results We screened out 178 differentially-expressed genes. After cluster analysis, CXCL9, CXCL10, NKX2-1 and SFTPA1 were regarded as the key genes of cisplatin resistance in lung adenocarcinoma. CXCL10 was temporarily selected for subsequent verification and function experiment. The mRNA expression of CXCL10 in A549/DDP cells was significantly higher than that in A549 cells (P < 0.001), and the expression of CXCL10 protein in the supernatant of A549/DDP cells was higher than that in A549 cells, which were consistent with the prediction of bioinformatics. The sensitivity of A549/DDP cells to DDP increased after silencing CXCL10 expression. Conclusions CXCL10 is a key gene to regulate cisplatin resistance in lung adenocarcinoma. Downregulating the expression of CXCL10 can become a potential target for reversing cisplatin resistance in lung adenocarcinoma.

Effect of recombinant trichosanthin on proliferation of human cevical cancer Caski cells / 中国中药杂志

<p><b>OBJECTIVE</b>To observe the effects of high expression of recombinant trichosanthin (rTCS) on the cell proliferation and cell cycle of human cervical cancer Caski cells.</p><p><b>METHOD</b>Eukaryotic expression plasmid pcDNA3.1(-)/6His-TCS was constracted and stably transfected into Caski cells. RT-PCR,Western-blot were used to select the clones with rTCS high-expressing. Using pcDNA3.1(-)-transfected cells as the control, MTT assay and flowcytometry were used to elucidate the effects of rTCS high expression on cell growth and cycle regulation in Caski cells.</p><p><b>RESULT</b>The Caski cells with stable high expression of rTCS was successfully established, which could inhibit the cell growth (P<0.01) and arrest Caski cells in G1 and G2 phases (P<0.05) obviously.</p><p><b>CONCLUSION</b>High expression of rTCS can inhibit the growth of Caski cervical cancer cells, which might provide a new pathway for the therapy of cervical cancer.</p>

In vitro introduction of recombinant trichosanthin on demethylation of p27 in HeLa cells / 中草药

Objective To investigate the effects of recombinant trichosanthin(rTCS) on methylation status and expression level of p27 gene in HeLa cells.Methods HeLa cells was treated by different concentration(20 ?g/mL,40 ?g/mL,and 80 ?g/mL) of rTCS for 48 h and then methylation-specific polymerase chain reaction(MSP) was used to detect the promoter methylation status of the p27 gene,real-time PCR was used to detect levels of p27 and DNMT1 mRNA,and Western blotting assay was used to detect expression level of p27 protein before and after treatment with rTCS.Results Low expression level and promoter methylation status of the p27 gene were detected in HeLa cells.Treatment with 40 ?g/mL rTCS totally demethylated p27 promoter.Treatment with 20 ?g/mL,40 ?g/mL or 80 ?g/mL rTCS resulted in a 2.22-,4.00-or 6.03-folds increase in p27 mRNA level,respectively,and also a great increase in p27 protein level.A high DNMT1 expression level was observed in HeLa cells and treatment with 40 ?g/mL rTCS resulted in a 78% decrease at the DNMT1 mRNA expression.Conclusion rTCS could reverse promoter hypermethylation and re-activate the expression of p27 gene by inhibiting DNMT1 expression in HeLa cells,which indicates its potential use in cancer therapy.