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In Vivo Antitumor Activity of HSV tk/CD Combinative Gene Toward Human Cholangiocarcinoma Cells(QBC939)

【Abstract】Objective To study the antitumor activity of HSVtk/CD combinative gene toward human cholangiocarcinoma in vivo. Methods Nude mouse models with transplanted subcutaneous cholangiocarcinoma were constructed and divided into 4 groups randomly, each group had 8 mice. Adenovirus solution free from suicide gene was injected in subcutaneous tumors of each mouse of control group. Adenovirus solution containing cytosine deaminase (CD), thymidine kinase (tk) and HSVtk/CD fusional gene were injected into single suicide gene either HSVtk or CD was transinfected into the tumor cells by injecting viras into subcutaneous tumor of mice of CD gene,tk gene and fused CD and tk gene group respectively. 24 hours after the injection, 5fluorocytosine (5FC) and ganciclovir (GCV) were injected introabdominally in each mouse. Growth of the tumors were monitored.Results Tumor growth of the genetransfection groups was suppressed in different degrees. Compared with the control group, the suppressing rates of the genetransfection groups were 41.2%, 55.7% and 70.0% respectively (P＜0.05). Histological examination showed good tumor growth in the control group, and tumor necrosis in the other 3 groups, particularly obvious in the group transfected with pAd(HSVtk/CD).Conclusion Combinative gene system has a b antitumor effect on cholangiocarcinoma in vivo. But it’s not powerful enough to eliminate tumor thoroughly because of insufficient “Bystander effect”.

MEDICAL APPLICATION OF NANO-MATERIALS

OBJECTIVE: To review the research progress and medical application of nano-materials. METHODS: The literature review and comprehensive analysis, methods were used in this study. RESULTS: The Nanotechnology is a typical crossing knowledge. It could be extensively applied in the fields of novel biomaterials, effective transmission of bioactive factor; the detection of functions for all vital organ systems, vascular circulation condition, the control of repair of burn trauma wounds will be monitored by the varied methods of nano technology combined with molecular biological engineering. CONCLUSION: The application of Nanotechnology will play important roles in clinical medicine, wound repair and basic research for the traditional Chinese medicine.

新生血管性眼病基因治疗的研究进展

随着对多种分子信号与新生血管关系的深入研究，发现促血管生成因子与抑制因子之间的失衡是新生血管生成的重要原因。基因治疗是指将基因导入人体细胞使其发挥生物学效应，从而治疗疾病的一种技术方法。应用基因转染技术将外源基因导入眼内，通过下调促血管生成因子的表达或上调抑制因子的表达，重塑其间的平衡，将为新生血管性眼病的防治提供新的思路。

Protection of retinal ganglion cells from optic nerve injury by brainderived neurotrophic factor transfected through microbubble contrast agent into the retina and visual cortex

　　Objective　To observe the protective effect of ultrasound microbubble contrast agentmediated transfection of brain-derived neurotrophic factor(BDNF) into the retina and visual cortex on retinal ganglion cells (RGC) after optic nerve injury. Methods　A total of 88 male Sprague-Dawley (SD) rats were randomly divided into normal group (group A, eight rats), sham operation group (group B, 16 rats), control group (group C, 16 rats), eyes transfection group (group D, 16 rats), brain transfection group (group E, 16 rats), combined transfection group (group F, 16 rats). The optic nerve crush injury was induced, and then the groups B to F were divided into one-week and two-week after optic nerve injury subgroup with eight rats each, respectively. The rats in group B and C underwent intravitreal and visual cortex injection with phosphate buffered solution respectively. The rats in group D and E underwent intravitreal and visual cortex injection with the mixture solution of microbubbles and BDNF plasmids respectively. The rats in group F underwent both intravitreal and visual cortex injection with the mixture solution of microbubbles and BDNF plasmids at the same time. The ultrasound exposure was performed on the rats in group D to F after injection with the mixture solution of microbubbles and BDNF plasmids. One and two weeks after optic nerve injury, RGC were retrogradely labeled with Fluorogold; active caspase-3 protein was observed by immunohistochemistry and the N95 amplitude was detected by pattern electroretinogram (PERG). Results　Golden fluorescence can be observed exactly in labeled RGC in all groups，the difference of the number of RGC between the six groups and ten subgroups were significant（F=256.30，65.18；P＜0.01）. Active caspase-3 in ganglion cell layer was detected in group C to F, but not in group A and B. The difference of the N95 amplitude between the six groups and ten subgroups were significant（F=121.56，82.38；P＜0.01）.Conclusion　Ultrasound microbubble contrast agent-mediated BDNF transfection to the rat retina and visual cortex can inhibit the RGC apoptosis after optic nerve injury and protect the visual function.

Inhibition of choroidal melanoma cell growth by electroporationmediated transfer of immunologic cytokines or antiangiogenesis genes

　　Objective　To observe the effects of immunologic cytokines or anti-angiogenesis gene transfer mediated by electroporation for choroidal melanoma cells.Methods　The human embryo kidney cells and malignant choroidal melanoma cells were transfected with plasmids pNGVL-mIL2, pNGVL-mIL12, pCI-sFLK-1, pCR3.1-antiVEGF121,pCI-ExTek. Then the expression of mIL2, mIL12, sFLK-1, VEGF and ExTek were detected by enzymelinked immunosorbentassay (ELISA) and Western blot. Nude mice models of malignant choroidal melanoma were established and they were divided into four groups randomly. Each group was treated with 30 mu;l of 0.9% NaCl, 30 mu;g pNGVL, 30 mu;g antiVEGF121+sFLK-1+ExTek and 30 mu;g mIL2+mIL12 respectively by electroporation. Seven，14, 21, 28, 35 and 42 days after treatment, the tumor volumes were measured to calculate the tumor inhibition rate. Results　ELISA and Western blot showed that mIL2，mIL12，sFLK-1 and ExTek were expressed after electroporation，VEGF expression was decreased remarkably. After treatment，the tumors of mIL2+mIL12 group were greatly inhibited with a tumor inhibition rate of 97.33%，while the tumors of antiVEGF121+sFLK-1+ExTek and pNGVL group were partially inhibited with tumor inhibition rates of 53.33% and 36.33% respectively.Conclusions　Immunologic cytokines transfer mediated by electroporation can inhibit the growth of melanoma，but anti-angiogenesis only have a mild effects.

Inhibition effect of complement factor small interference RNA on the angiogenesis of choroidal neovascularization induced by photocoagulation in rats

Objective To observe the inhibitory effects of construction of complement factor (CFB)small interference RNA (siRNA) on choroidal neovascularization（CNV）induced by photocoagulation in rats.Methods We constructed an expression vector of CFBsiRNA by cutting CFBsiRNA and plasmid pRNATU61/Neo. Experimental CNV was induced by photocoagulation in 42 Brown Norway rats. After the model was set up, the rats were randomly divided into tail intravenous injection, vitreous injection, subretinal injection, and control group; each group except the control one had a corresponding blank plasmid control group. CFBsiRNA was injected 1, 3, and 5 days respectively after photocoagulation in the injection groups; the dosage was 50, 20, and 10 mu;g in tail intravenous injection, vitreous injection, and subretinal injection group respectively, while no injection was give to the control group after photocoagulation. Before and 14 days after photocoagulation, fundus fluorescein angiograoph (FFA) was performed and CNV development was judged by the leakage; the expression of vascular endothelial growth factor (VEGF) and factor Ⅷ were detected by immunohistochemistry. Results The leakage of fluorescein was obvious lower in tail intravenous injection group than that in the control group (chi;2=15.1620,Plt;0.05). The expression of VEGF and factor VIII in tail intravenous injection group at different time points after photocoagulation didnprime;tdiffer much (F=20.35,18.33; Pgt;0.05); while was apparently lower than that in the other groups at different time points (F=77.96,55.68; Plt;0.05).All of the groups, except tail intravenous injection group, had higher expression of VEGF and factor VIII 14 days after photocoagulation compared with that 7 days after photocoagulation (F=60.89, 61.12; Plt;0.05).Conclusions Constructed CFBsiRNA can inhibite CNV by downregulating the expression of VEGF and factor Ⅷ.

Gene transfection into retinal pigment epithelial cells and photoreceptors using in vivo electroporation

Objective 　To investigate the feasibility of gene transfection into retinal pigment epithelial (RPE) cells and photoreceptors (PRs) in vivo electroporation. Methods　 A total of 147 Sprague-Dawley (SD) rats were divided into 5, 10, 15, 20, 25, 30 and 35 V group according to different voltage. The right eyes of rats underwent the injection of eukaryotic expressive plasmid of enhanced green fluorescent protein (EGFP) pEGFP-N1 into subretinal space as experimental eyes; the left eyes were injected with TE buffer as control eyes. Each group was divided into RPE and RP subgroups according to different transfection direction. There were same parameters of 99 ms pulse width, 0.5 s pulse interval and 5 consecutive pulses except different voltage in groups. With a negative charge in the electric field was transfected into RPE cell layer, reverse electrode set to be transfected into PR cell layer. Retina mounts were made on seven days after transfection and the fluorescence of EGFP was photographed by fluorescent microscope. The expression of EGFP mRNA and protein were detected by reverse transcription polymerase chain reaction technique (RT-PCR) and Western blot.Results 　On seven days after transfection, in RPE subgroups, there were no specific fluorescence expressions in RPE cell layer and retina mounts of control eyes, while there were fluorescence expressions in experimental eyes. Western blot showed that the grayscale ratio of EGFP protein and beta;actin protein bands rose with the increased voltage. RT-PCR showed that each group produced positive amplification bands, and the relative ratio of gray level of EGFP mRNA and GADPH mRNA amplified bands gradually increased with the increased voltage.Conclusion 　Electroporation is an effective method for gene delivery into RPE cells in vivo.

视网膜色素变性基因治疗的研究现状及展望

Therapeutic strategy for retinoblastoma in China

Retinoblastoma (RB) is the most common intraocular malignant tumor in children. With advanced clinical technologies there are more and more methods available to treat retinoblastoma, and make it is possible to delivery individualized protocol combined traditional treatments with modern regimen to patients now. In order to improve the survival rate and the life quality of RB patients in China, it is very important to make a suitable system of standardized therapy based on results from developed countries and health policies of our own country.

虹膜色素上皮细胞移植的研究进展

虹膜色素上皮（IPE）细胞是一种胚胎发育与视网膜色素上皮（RPE）细胞同源的生长细胞，不仅在结构上与RPE细胞有着惊人的相似之处，而且在吞噬视杆细胞外节段和分泌细胞因子等功能方面也有显著一致性。利用基因转染等方法将IPE细胞移植到视网膜下腔不仅可以应用于遗传性视网膜变性，老年性相关变性等眼科疾病的治疗，同时还可以应用于神经退行性疾病的治疗。关注IPE细胞的功能特性及其移植方法的研究现状和应用前景具有重要的临床意义。现就IPE细胞的功能特性及研究进展作一综述。