肿瘤药物敏感基因的研究进展

用肿瘤药物敏感基因转染肿瘤细胞,可提高肿瘤细胞对药物的敏感性,使药物选择性地杀死肿瘤细胞而对正常细胞不产生毒性。本文综述药物敏感基因的研究进展。

Effect of dietary supplementation with discardednutrient medium of Cordyceps militaris on layingperformance and diversity of intestinal flora in laying hens

The aim of the experiment was to explore the feasibility of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens. 100 g/kg, 200 g/kg, 300 g/kg of discarded nutrient medium of Cordyceps militaris were added to the basal diet of laying hens. The results showed that the optimal addition of discarded nutrient medium of Cordyceps militaris in the diet of laying hens was 10%. According to the results of measuring the conventional indicators of eggs, the weight of eggs produced by laying hens fed with discarded nutrient medium of Cordyceps militaris was higher than that of laying hens fed with ordinary laying hens. The content of interleukin-1(IL-1) in the experimental group was significantly higher than that in the control group, and the concentration of IL-1 increased by 141.5 pg/mL, which indicated that the application of discarded nutrient medium of Cordyceps militaris effectively improved the immunity of laying hens. The high-throughput analysis of the intestinal contents of the two groups of laying hens showed that the microbial population abundance of the intestinal tract of the experimental group was greater than that of control group, and the application of discarded nutrient medium of Cordyceps militaris increased the diversity of bacteria in the intestinal tract of laying hens. In addition, the sensitivity of some pathogenic bacteria in the intestinal tract of chickens to drugs was also increased, thereby reducing the use of antibiotics. The secondary utilization of discarded nutrient medium of Cordyceps militaris has great development and utilization prospects, which provided a scientific reference and basic theoretical basis for the development of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens.

Genistein sensitizes ovarian carcinoma cells to chemotherapy by switching the cell cycle progression in vitro

Objective:To address how genistein sensitizes the chemotherapy-resistant ovarian carcinoma cells and promotes apoptosis in the respect of cell cycle and the regulation of survivin expression in the process.Methods:Ovarian SKOV-3 carcinoma cell line was treated with genistein or cisplatin either alone or in combination.Cell viability was showed by MTT method.Cell cycle and apoptosis were detected by flow cytometry.Survivin mRNA and protein were revealed by RT-PCR and immunocytochemistry,respectively.Results:Genistein could reduce the cell viability in a dose-dependent manner,while cisplatin did so at a much higher level.In contrast,if the two agents were treated in combination,half growth inhibition(IC50) value for cisplatin was reduced remarkably and the effect was synergistic as analyzed by isobologram.In particular,the reduced cell viability was exhibited by a switch in cell cycle progression,as the cells were arrested in G2/M phase and the G0/G1 phase-fraction was significantly decreased.The reduced cell viability appeared to involve apoptosis,based on our results from flow cytometry and Hoechst 33258 staining.In the meanwhile,genistein performed the inhibitory effect on cisplatin-induced survivin expression.Conclusion:Genistein can sensitize ovarian carcinoma cells to cisplatin therapy with the inhibition of survivin expression as the potential mechanism.

Detecting of PPNG by Molecular Biology Technique

Objective: To investigate the prevalence ofpenicillinase-producing Neisseria gonorrhoeae (PPNG) inWuxi. Methods: Nested PCR (nPCR) was used to test for thepresence of β-lactamase DNA in urethral or cervical swabsspecimens from 217 patients with gonorrhea. OnenPCR-positive product was randomly selected for DNAsequencing. Results: PPNG was found in 60 of all 217 specimens(27.65%), and in 33.87% (42/124) of male and 19.35%(18/93) of female cases. The nPCR product was identical toa known clinical PPNG strain. Conclusion: The prevalence of PPNG in STD patients inWuxi is alarmingly high, and this must be taken intoconsideration for successful treatment and prevention ofgonorrhea infections.

Research progress in the use of combinations of platinum-based chemotherapy and epidermal growth factor receptor-tyrosine kinase inhibitors

In the past decade,the advent of the epidermal growth factor receptor-tyrosine kinase inhibitors(EGFR-TKIs)has dramatically influenced the therapeutic strategies for treating lung cancer,but with tumor progression and drug resistance,patients will ultimately develop reduced sensitivity to EGFR-TKIs.How can we delay the emergence of drug resistance? What is the next strategy after drug resistance? How to reasonably combine platinum-based chemotherapy and EGFR-TKIs? These questions are currently the focus of lung cancer research.Clinical studies have reported that platinum-based chemotherapy can increase the sensitivity to EGFR-TKIs.However,results of pre-clinical and clinical studies have been inconsistent.The mechanisms of platinum chemotherapy and EGFR-TKIs are still unknown due to the lack of systematic research.Therefore,systematic studies are required to show the mechanisms of EGFR-TKIs and chemotherapy agents and define the markers sensitive to their combinations when given concurrently or sequentially.

Recombinant expression of different mutant K-ras gene in pancreatic cancer Bxpc-3 cells and its effects on chemotherapy sensitivity

K-ras is a member of ras gene family which is involved in cell survival,proliferation and differentiation.When a mutation occurs in ras gene,the activation of Ras proteins may be prolonged to induce oncogenesis.However,the relationship between K-ras mutation and clinical outcomes in pancreatic cancer patients treated with chemotherapy agents is still under debate.In this study,we constructed five pAcGFP1-C3 plasmids for different types of K-ras gene(WT,G12V,G12R,G12D,and G13D)and stably transfected human pancreatic cancer Bxpc-3 cells with these genes.The wild type and mutant clones showed a comparable growth and expression of K-Ras-GFP fusion protein.The expression of some K-ras mutations resulted in a reduced sensitivity to gefitinib,5-FU,docetaxel and gemcitabine,while showed no effects on erlotinib or cisplatin.Moreover,compared with the wild type clone,K-Ras downstream signals(phospho-Akt and/or phospho-Erk)were increased in K-ras mutant clones.Interestingly,different types of K-ras mutation had non-identical K-Ras downstream signal activities and drug responses.Our results are the first to reveal the relationship between different K-ras mutation and drug sensitivities of these anti-cancer drugs in pancreatic cancer cells in vitro.