A small proportion of many cancers are due to inherited mutations in genes, which result in a high risk to the individual of developing specific cancers. There are several classes of genes that may be involved: tumour suppressor genes, oncogenes, genes encoding proteins involved in DNA repair and cell cycle control, and genes involved in stimulating the angiogenic pathway. Alterations in susceptibility to cancer may also be due to variations in genes involved in carcinogen metabolism. This review discusses examples of some of these genes and the associated clinical conditions caused by the inheritance of mutations in such genes.
DNA Repair ; genetics ; Genes, Tumor Suppressor ; Genetic Predisposition to Disease ; Humans ; Neoplasms ; genetics ; Neovascularization, Physiologic ; genetics ; Oncogenes

OBJECTIVETo explore a new method for the therapy of avascular necrosis of the femoral head.

METHODSThe recombinant plasmid pCD-hVEGF165 was mixed with collagen and was implanted in the necrotic femoral head. The expression of vascular endothelial growth factor (VEGF) was examined by RNA dot hybridization and immunohistochemical techniques. Repair of the femoral head was observed by histological and histomorphometric analysis.

RESULTSThe expression of VEGF was detected in the femoral head transfected with the VEGF gene. The femoral head transfected with the VEGF gene showed a significant increase in angiogenesis 2 and 4 weeks after gene transfection and a significant increase in bone formation 6 and 8 weeks after gene transfection on histomorphometric analysis (P < 0.01).

CONCLUSIONSTransfection of the VEGF gene enhances bone tissue angiogenesis. Repair of osteonecrosis could be accelerated accordingly, thus providing a potential method for therapy of osteonecrosis.

Animals ; Femur Head Necrosis ; therapy ; Neovascularization, Physiologic ; Rabbits ; Random Allocation ; Transfection ; Vascular Endothelial Growth Factor A ; genetics

This study was purposed to investigate the angiogenesis-promoting activities of human mesenchymal stem cells (hMSCs) modified by hepatocyte growth factor (HGF) and the underlying mechanisms. The hMSCs were transfected by recombinant adenoviral vector carrying human HGF gene and seeded onto the chicken chorioallantoic membrane. Three days later, the number of blood vessels was counted and their angiogenic response was compared with those of hMSCs of same generation, recombinant basic fibroblast growth factor (bFGF) and alpha-MEM as control. The expression levels of bFGF, VEGF, angiopoietin-1 and angiopoietin-2 were evaluated by RT-PCR assay. The results showed that gene-modified hMSCs exhibited greatest activity to promote angiogenesis while the angiogenic response was nearly same between groups treated by hMSCs and bFGF, all of which were significantly higher than that observed in control (p < 0.01). RT-PCR analysis revealed that hMSCs constitutively expressed multiple angiogenesis-associated growth factors and their levels seemed up-regulated by HGF gene transfer. It is concluded that HGF gene-modified hMSCs show a potent angiogenesis-promoting function and may be useful in the treatment of ischemic disorders.
Animals ; Cells, Cultured ; Chick Embryo ; Chickens ; Hepatocyte Growth Factor ; genetics ; Humans ; Mesenchymal Stromal Cells ; Neovascularization, Physiologic ; genetics ; Transfection

Anemia ; metabolism ; physiopathology ; Animals ; Cell Hypoxia ; Genetic Therapy ; Humans ; Hypoxia-Inducible Factor 1 ; genetics ; metabolism ; physiology ; Neovascularization, Pathologic ; metabolism ; pathology ; Neovascularization, Physiologic ; Osteogenesis ; RNA, Messenger ; metabolism

OBJECTIVETo investigate the effect of adenoviral-mediated exogenous HGF (Ad-HGF) gene transfer on lung angiogenesis in the rabbit lung in rabbits with hyperkinetic pulmonary artery hypertension.

METHODSA thoracotomy was performed through a midsternal incision in 1-month-old immature rabbit and an anastomosis between the left innominate artery and the pulmonary trunk was made to establish a chronic patent left to right shunt. Three months later, animals were randomly assigned to receive either Ad-HGF (2 x 10(9) Pfu in 0.2 ml PBS, H1 group), repeated administration of Ad-HGF after one week (H 2 group), Ad-GFP (2 x 10(9) Pfu in 0.2 ml PBS, G group), or PBS (0.2 ml, C group) by the intratracheal method of gene transfection. After two weeks, reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemical examination was performed to identify HGF mRNA and HGF protein expression. The capillary density and small pulmonary artery density were determined by immunostained with antibodies against factor VIII and alpha-SMA. After 1 month, the collateral vessels were evaluated by angiogram under digital subtraction angiography (DSA).

RESULTSTwo weeks after Ad-HGF transfection, 484 bp bands could be found by RT-PCR in H1 and H2 groups, but not in other groups. The expression of HGF protein could be detected on alveolar epithelium and pulmonary vessel endothelium by immunohistochemistry examination. The number of factor VIII-positive pulmonary capillaries was also significantly increased in the H1 and H2 groups compared with the C and G groups (P < 0.05). The capillary density reached (17.0 +/- 3.3) mm(2) and (19.7 +/- 2.8) mm(2) in the H1 and H2 group, respectively, whereas it remained (13.2 +/- 3.2) mm(2) in the C group and (13.5 +/- 2.4) mm(2) in the G group (P < 0.05). One month after Ad-HGF transfection, the number of small pulmonary arteries was significantly increased in H1 and H2 group compared with control groups (P < 0.05). The collateral vessels were more abundant in HGF transfection groups than that in the two control groups reviewed by angiogram under digital subtraction angiography (DSA).

CONCLUSIONIn vivo gene transfection with HGF by means of the intra-tracheal injection could induce pulmonary angiogenesis in the early stage and small pulmonary arterial angiogenesis in later stage.

Animals ; Disease Models, Animal ; Female ; Hepatocyte Growth Factor ; genetics ; Hypertension, Pulmonary ; physiopathology ; Lung ; blood supply ; Male ; Neovascularization, Physiologic ; Rabbits ; Transfection

Tumor angiogenesis plays a pivotal role in the progress of tumor. Among the various endogenous angiogenic inhibitors discovered, the human plasminogen kringle 5 (K5) has been demonstrated to be a potential inhibitor of the proliferation and migration of vascular endothelial cells in vitro. The replication-incompetent adenovirus (Ad) vector Adeno-X-CMV-K5 (Ad-K5) (where CMV is cytomegalovirus) was constructed and its antiangiogenic effect was tested on vascular endothelial cell and tumor cell. For the construction, the K5 cDNA was fused in-frame with human plasminogen signal sequence and inserted into the eukaryotic expression vector pcDNA3 to form pcDNA3K5. The recombinant plasmid was subcloned into the shuttle plasmid pShuttle under the control of the constitutive CMV immediate-early promoter. The plasmid carrying the cDNA for K5 (pShuttleKS) was then recombined with the Adeno-X viral DNA and transformed into E. coli DH5alpha. The resultant recombinant plasmid pAd-K5 was transfected into human embryonic kidney (HEK) 293 cells with liposome. The adenovirus expressing human plasminogen kringle 5 (Ad-K5) was successfully packaged and propagated in 293 cells, as detected by the cytopathic effect (CPE) on the cells, and the viral titer in the supernatant was 5 x 10(8) pfu/mL by plaque assay. Both human umbilical vein endothelial cell line ECV304 and human breast carcinoma cell line MDA-MB-231 were infected with Ad-K5 and Ad-LacZ, which was used the negative control, and assayed by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Compared with uninfected control and Ad-LacZ infected control, Ad-K5 infected group at 80 MOI (multiplicity of infection) significantly inhibited ECV304 proliferation; the difference between uninfected control and Ad-LacZ infected control was not significant. In contrast, there was no significant difference in the proliferation of MDA-MB-231 among all the treatments. In addition, the Ad-K5 at 100 MOI inhibited the differentiation and tube formation of ECV304 on ECMatrix gel. These results suggested that the recombinant replication-defective Adenovirus expressing human plasminogen kringle 5 inhibited the proliferation, differentiation and tube formation of ECV304 and had no effect on the proliferation of MDA-MB-231. Adenovirus mediated human plasminogen kringle 5 gene therapy may be a potential treatment of cancer through angiogenesis inhibition.
Adenoviridae ; genetics ; Cell Line ; Cell Line, Tumor ; Cell Proliferation ; Genetic Vectors ; genetics ; Humans ; Neovascularization, Physiologic ; genetics ; physiology ; Peptide Fragments ; genetics ; physiology ; Plasminogen ; genetics ; physiology ; Polymerase Chain Reaction

OBJECTIVESTo investigate the impact of AAV-encoding NT4-TAT-His-PR39 fusion gene expression on HIF-1alpha level in ECV304 cultured under hypoxic condition (1%O(2)) and on angiogenesis in hypoxic chick embryo.

METHODSPR39 cDNA was connected with NT4, TAT, 6 x His cDNA by molecular biology methods. The recombinant AAV vector was obtained by three plasmid co-transfection in 293 cells. Then ECV304 were respectively infected with AAV-NT4-TAT-His-PR39, 6 x His expression and HIF-1alpha level in ECV304 were detected by immunocytochemistry. The chicken embryos were randomized into the AAV-PR39, EV and PBS groups (n = 10 each) subject to hypoxia (5%O(2), n = 15) or normoxia environments (n = 15), the vessel density of the chicken chorioallantoic membrane (CAM) were measured by Image Pro Plus (IPP) software.

RESULTSThe expression of 6 x His protein was detected in AAV-PR39 infected ECV304 cells. HIF-1alpha protein activity was significantly increased in AAV-PR39 infected ECV304 underwent hypoxia compared to PBS and non-infected ECV304 groups (P < 0.05). The vessel density of chicken CAM in hypoxia environment but not in normoxia environment was also significantly higher in AAV-PR39 group than in EV group and PBS group (all P < 0.05).

CONCLUSIONAAV-encoding NT4-TAT-His-PR39 fusion gene expression significantly increased HIF-1alpha level in ECV304 exposed to hypoxia and promoted angiogenesis in hypoxic chicken embryo.

Animals ; Antimicrobial Cationic Peptides ; genetics ; Cell Line ; Chick Embryo ; Dependovirus ; genetics ; Gene Fusion ; Gene Transfer Techniques ; Genes, Viral ; Hypoxia ; genetics ; Neovascularization, Physiologic ; genetics

OBJECTIVETo establish transgenic mice with GFP expression in the vascular endothelium during neovascularization.

METHODSThe vector nestin-hsp68-gfp containing nestin second intron was introduced into U251 cells and the expression level of GFP was detected by fluorescence microscopy. Transgenic mice were produced by microinjection. The genome of the offspring mice was screened by PCR, and GFP expression in the vascular endothelium was detected using immunohistochemistry.

RESULTSThirteen offspring mice were obtained and 2 of them were positive for GFP in the vascular endothelium as detected by PCR. GFP was detected in the offspring mice both at the embryonic stage and after birth.

CONCLUSIONSThe transgenic mice with GFP expression in the vascular endothelium during neovascularization have been successfully established.

Animals ; Animals, Newborn ; Base Sequence ; Endothelium, Vascular ; metabolism ; Green Fluorescent Proteins ; biosynthesis ; genetics ; Intermediate Filament Proteins ; biosynthesis ; genetics ; Mice ; Mice, Transgenic ; Molecular Sequence Data ; Neovascularization, Pathologic ; genetics ; Neovascularization, Physiologic ; genetics ; Nerve Tissue Proteins ; biosynthesis ; genetics ; Nestin

Progressive tumor growth is dependent on angiogenesis. The mechanisms by which endothelial cells (ECs) are incorporated to develop new blood vessels are not well understood. Recent studies reveal that the ezrin radixin moesin (ERM) family members are key regulators of cellular activities such as adhesion, morphogenetic change, and migration. We hypothesized that ezrin, one of the ERM family members, may play important roles in ECs organization during angiogenesis, and new vessels formation in preexisting tissues. To test this hypothesis, in this study, we investigated the effects of ezrin gene silencing on the migration and angiogenesis of human umbilical vein endothelial cells (HUVECs) in vitro. HUVECs were transfected with plasmids with ezrin-targeting short hairpin RNA by using the lipofectamine-2000 system. Wound assay in vitro and three-dimensional culture were used to detect the migration and angiogenesis capacity of HUVECs. The morphological changes of transfected cells were observed by confocal and phase contrast microscopy. Our results demonstrated that the decreased expression of ezrin in HUVECs significantly induced the morphogenetic changes and cytoskeletal reorganization of the transfected cells, and also reduced cell migration and angiogenesis capacity in vitro, suggesting that ezrin play an important role in the process of HUVECs migration and angiogenesis.
Cell Movement ; genetics ; Cytoskeletal Proteins ; genetics ; metabolism ; Cytoskeleton ; metabolism ; Human Umbilical Vein Endothelial Cells ; cytology ; metabolism ; physiology ; Humans ; Neovascularization, Physiologic ; genetics

OBJECTIVETo establish experimental models for tumor neovascularization and to apply quantitative digital imaging analysis in the study.

METHODSAn endothelial tube formation model was established by human umbilical vein endothelial cells (HUVECs). A vasculogenic mimicry model was established by SGC-7901 gastric cancer cell line. Fertilized eggs were used to establish a chorioallantoic membrane angiogenesis model. Using gene transfection experiment, IRX1 tumor suppressor gene was chosen as a therapeutic target. Image Pro Plus (IPP) analysis software was used for digital vascular images analysis with parameters including points, lines, angles and integral absorbance (IA) for the tubular formation or vasculogenic mimicry.

RESULTSDigital image analysis by IPP showed that HUVEC tubular formation was significantly inhibited in IRX1 transfectant, compared with controls. The tubular numbers in three groups were 12.80 +/- 3.83, 29.00 +/- 5.34 and 28.20 +/- 4.32 (P<0.01). The connection points of tubules in three groups were 13.20 +/- 2.59, 25.00 +/- 2.24 and 24.60 +/- 3.21 (P<0.01). The tubular lengths of three groups were (821.5 +/- 12.5), (930.9 +/- 13.5) and (948.4 +/- 18.1) microm (P=0.022). The IA values of PAS stain in three groups were 3606 +/- 363, 14 200 +/- 1251 and 15 043 +/- 1220 (P<0.01). In chick chorioallantoic membrane model, the angular numbers of tubules in three groups were 6.41 +/- 2.60, 10.27 +/- 2.65 and 9.18 +/- 1.99 (P<0.01).

CONCLUSIONSThe endothelial tube formation model, vasculogenic mimicry model and chorioallantoic membrane angiogenesis model are useful for gene therapy and drug screening with targeting neoplastic vascularization. Professional image analysis software may greatly facilitate the quantitative analysis of tumor neovascularization.

Animals ; Cell Line, Tumor ; Cells, Cultured ; Chorioallantoic Membrane ; blood supply ; Diagnostic Imaging ; methods ; Homeodomain Proteins ; genetics ; metabolism ; physiology ; Human Umbilical Vein Endothelial Cells ; Humans ; Neovascularization, Pathologic ; Neovascularization, Physiologic ; Software ; Stomach Neoplasms ; genetics ; metabolism ; pathology ; Transcription Factors ; genetics ; metabolism ; physiology ; Transfection