Killing effect improved by fusion gene HRE1.Egr-1. yCDglyTK on gene-radio therapy of nasopharyngeal cancer in vitro / 中南大学学报(医学版)

OBJECTIVE@#To construct hypoxia/radiation inducible promotor HRE1.Egr-1, and to observe its promotive effect on the expression of yCDglyTK gene in nasopharyngeal cancer HNE-1 cells and the anti-tumor effect of yCDglyTK and to lay an experimental foundation for further exploration of new gene-radio therapy of nasopharyngeal cancer.@*METHODS@#pcDNA3.1(-)HRE1.Egr-1.yCDglyTK was constructed by gene recombination technique. Stable yCDglyTK-expressing HNE-1 cells were generated by transfecting the recombinant plasmid into the target cells with liposome. The expression of yCDglyTK was detected by Western blot in 4 groups: a normoxia group, a radiation group, a hypoxia group, and a hypoxia and radiation group. The killing effect of 5-FC in different circumstances was determined by MTT.@*RESULTS@#The expression of yCDglyTK/5-FC gene in all the groups was significantly different(P<0.01),especially in the hypoxia and radiation group. The killing effect of 5-FC on HNE1 cells varied under different conditions, especially in the hypoxia and radiation group.@*CONCLUSION@#Hypoxia and radiation can induce the activity of fusion promoter HRE1.Egr-1, and obviously promote the anti-tumor effect of yCDglyTK/5-FC system, suggesting that yCDglyTK may be a candidate suicide gene for gene-radio therapy of NPC.

Combining FCU/5-FU suicide gene/prodrug system and radiation in treating nasopharyngeal carcinoma: an experimental study / 中华病理学杂志

<p><b>OBJECTIVE</b>To explore the in vitro, in situ and in vivo killing effects to CNE-2 cells of human nasopharyngeal carcinoma (NPC) by FCU/5-FC system combined with gamma irradiation for predicting the treatment effect on NPC.</p><p><b>METHODS</b>Plasmid pcDNA3.1(-)CMVe.Egr-1. FCU was introduced into CNE-2 cells by electroporation. The transfected cells were selected by G418 (600 microg/ml) for 14 days to yield cells expressing FCU stably. The FCU protein in transfected CNE-2 cells was tested by Western blotting. In vitro response of FCU-expressing CNE-2 cells to 5-FC or gamma irradiation, alone or in combination was detected by MTT assay. Furthermore, A NPC model was employed by inoculating CNE-2 cells in the right flank of nude mice for in situ gene therapy, and after 12 days of inoculation, those rats were randomized to seven groups, then the suppression of NPC growth in model was observed after giving different treatments. Finally, FCU-expressing CNE-2 cells were inoculating in the right flank of nude mice to generate NPC xenografts for in vivo gene therapy, and after 5-day of implantation, those rats were randomized to seven groups, then the delaying of tumour growth was observed in xenografts treated with different conditions.</p><p><b>RESULTS</b>A anticipated relative molecular quality 42,000 protein was obtained from total protein of FCU-expressing CNE-2 cells. The growth of FCU-positive CNE-2 cells were inhibited by 5-FC or gamma irradiation, alone or in combination, but cells treated with both 5-FC and gamma irradiation resulted in enhanced cell killing when compared with cells treated with gamma irradiation or 5-FC alone. In vitro study showed that the relative survival rates of FCU-expressing CNE-2 cells treated with gamma irradiation were 15.85% - 97.88%, while that of gamma irradiation + 5-FC (100 microg/ml) group were 6.58% - 50.00%, and there was a significant difference (P < 0.01). The MTT results also demonstrated that the relative survival rate has a striking different (P < 0.01) between 5-FC group (12.11% - 99.51%) and 5-FC + gamma irradiation (1.0 Gy) group (2.37% - 35.87%). Not only in situ but also in vivo, potent growth inhibition on the explanted NPC tumours was observed in mice treated with 5-FC or gamma irradiation, alone or in combination, among which interference of both 5-FC and gamma irradiation leaded to most distinct suppression of tumour growth. Tumour volumes in groups interfered by 5-FC and or gamma irradiation were extinctly different with the control group and PBS treatment group (P < 0.05).</p><p><b>CONCLUSION</b>CNE-2 cells or nasopharyngeal carcinoma venograph could be killed by FCU/5-FC suicide gene prodrug system or gamma irradiation, and there is a synergistic therapeutic effect on NPC between FCU/5-FC and gamma irradiation.</p>

Clinical analysis of pneumomediastinum or pneumothorax during the removal of brochial foreign bodies / 中南大学学报(医学版)

OBJECTIVE@#To discuss the etiology, diagnosis, treatment, and prevention of pneumomediastinum or pneumothorax during the removal of bronchial foreign bodies in children.@*METHODS@#We analyzed the clinical data of 10 cases of pneumomediastinum or pneumothorax during the removal of bronchial foreign bodies in children.@*RESULTS@#Two patients died and the other 8 were cured.@*CONCLUSION@#Pneumomediastinum or pneumothorax is mainly caused by the intrapulmonary hyper-pressure and fracture of pulmonary bubbles. The prognosis of pneumomediastinum or pneumothorax is closely related to such factors as correct and punctual diagnosis and quick removal of the airway obstruction.

Killing effect of VP3 on human nasopharyngeal carcinoma cell line CNE-2 cells / 中南大学学报(医学版)

OBJECTIVE@#To investigate the killing effects of VP(3) on nasopharyngeal carcinoma cell line CNE-2.@*METHODS@#Plasmid expression vector pcDNA3.1(-) CMV.VP(3)-His was constructed and identified by Kpn I/EcoR I endonuclease analysis, and then sequenced to verify successful insertion in the sense direction of VP(3) gene. pcDNA3.1(-) CMV.VP(3)-His and pcDNA3.1(-)-His expression plasmid was transiently transfected into nasopharyngeal carcinoma cell line CNE-2 . VP(3) protein expression was detected by Western blotting. MTT assay was used to determine the killing effects of VP(3) gene on nasopharyngeal carcinoma cell line CNE-2.@*RESULTS@#Endonuclease analysis and sequencing confirmed the recombinant plasmid contained the complete VP(3) CDS sequence. Western blotting detected a 14.03 kD protein expression from the transfected cells, which was the expecting band of VP(3) gene. The growth of CNE-2 cells that expressed VP(3) gene was inhibited,while the growth of CNE-2 cells that did not express VP(3) gene was not inhibited.@*CONCLUSION@#VP(3) gene can kill nasopharyngeal carcinoma cell CNE-2.