EXPRESSION OF TOMATO ANTISENSE ACC SYNTHASE GENE IN TRANSGENIC TOBACCO AND ITS ROLE IN SHOOT FORMATION

An ACC synthase cDNA isolated from tomato (Lycopersicum esculentum Mill.) fruit was constructed in antisense orientation under the transcriptional control of CaMV 35S promoter and then introduced into tobacco (Nicotiana tabacum L.) . PCR amplification demonstrated the integration of this antisense gene in tobacco genomes. Northern hybridization and reverse transcription-PCR analyses indicated the expression of this heterologous antisense gene in the transgenic tobacco tissues, which caused a decrease in the ethylene production, particularly when shoot regeneration exhibited. The ability of shoot regeneration of the transgenic plant during the culture process was enhanced remarkably as compared with that of the control. These results indicate at the molecular level that ethylene may play a regulatory role in shoot formation.

Transduction of Fas gene or Bcl-2 antisense RNA sensitizes cultured drug resistant gastric cancer cells to chemotherapeutic drugs

AIM To compare the expression level of Fas gene and Bcl-2 gene in gastric cancer cells SGC7901 and gastric cancer MDR (multidrug resistant) cells SGC7901/VCR, to transduce Fas cDNA and Bcl-2 antisense nucleic acid into SGC7901/VCR cells respectively, and to observe the expression of two genes in transfectants and non-transfectants as well as their drug sensitivity.METHODS Eukaryotic expression vector pBK-Fas cDNA and pDOR-anti Bcl-2 were constructed and transfected into SGC7901/VCR cells by lipofectamine, respectively. Northern blot and Western blot were used to detect the expression of mRNA and protein in SGC7901/VCR and SGC7901 cells and transfectants, and drug sensitivity of transfectants for VCR, CDDP and 5-FU was analyzed with MTT assay.RESULTS After gene transfection, 80 for Fas and 120 for antisense Bcl-2 drug-resistant clones were selected from 2×105 cells, transfection rate being 0.04% and 0.06%. Two clones of SGC7901 Fas/VCR cells and SGC7901 anti Bcl-2/VCR cells were randomly selected for further incubation. Hybridization results showed that the expression level of Fas mRNA and protein in SGC7901/VCR cells was much lower, but that of Bcl-2 mRNA and protein was higher than that in SGC7901 cells. The expression of Fas mRNA and protein in SGC7901 Fas/VCR cells was higher, and of Bcl-2 mRNA and protein was lower in SGC7901 anti Bcl-2/VCR cells than that in non-transfectants. MTT assay showed that transfectants were more sensitive to VCR, CDDP, 5-FU than non-transfectants.CONCLUSION Bcl-2 gene displayed high expression while Fas gene had low expression in drug resistant gastric cancer cells. Expression of Bcl-2 protein was effectively blocked in SGC7901 anti Bcl-2/VCR cells by gene transfection. In contrast, the expression of Fas mRNA and protein in SGC7901 Fas/VCR cells increased. Fas gene and Bcl-2 antisense nucleic acid transfection sensitized drug resistant gastric cancer cells to chemotherapeutic drugs. These results suggest cell apoptosis plays an important role in the mechanism of MDR, and enhancing apoptosis might reverse MDR.

Reduction of tumorigenicity of SMMC-7721 hepatoma cells by vascular endothelial growth factor antisense gene therapy

AIM: To test the hypothesis to block VEGF expression of SMMC-7721 hepatoma cells may inhibit tumor growth using the rat hepatoma model. METHODS: Amplify the 200 VEGF cDNA fragment and insert it into human U6 gene cassette in the reverse orientation transcribing small antisense RNA which could specifically interact with VEGF165, and VEGF121 mRNA. Construct the retroviral vector containing this antisense VEGF U6 cassette and package the replication-deficient recombinant retrovirus. SMMC-7721 cells were transduced with these virus and positive clones were selected with G418. PCR and Southern blot analysis were performed to determine if U6 cassette integrated into the genomic DNA of positive clone. Transfected tumor cells were evaluated for RNA expression by ribonuclease protection assays. The VEGF protein in the supernatant of parental tumor cells and genetically modified tumor cells was determined with ELISA. In vitro and in vivo growth properties of antisense VEGF cell clone in nude mice were analyzed. RESULTS: Restriction enzyme digestion and PCR sequencing verified that the antisense VEGF RNA retroviral vector was successfully constructed.After G418 selection, resistant SMMC-7721 cell clone was picked up. PCR and Southern blot analysis suggested that U6 cassette was integrated into the cell genomic DNA. Stable SMMC-7721 cell clone transduced with U6 antisense RNA cassette could express 200 bp small antisense VEGF RNA and secrete reduced levels of VEGF in culture condition. Production of VEGF by antisense transgene-expressing cells was 65+/-10 ng/L per 10(6) cells, 42045 ng/L per 10(6) cells in sense group and 485+/-30 ng/L per 10(6) cells in the negative control group, (P【 0.05). The antisense-VEGF cell clone appeared phenotypically indistinguishable from SMMC-7721 cells and SMMC-7721 cells transfected sense VEGF. The growth rate of the antisense-VEGF cell clone was the same as the control cells. When S.C. was implanted into nude mice, growth of antisense-VEGF cell lines was greatly inhibited compared with control cells. CONCLUSION: Expression of antisense VEGF RNA in SMMC-7721 cells could decrease the tumorigenicity, and antisense-VEGF gene therapy may be an adjuvant treatment for hepatoma.

Inhibition of HSP70 Gene Expression by Modified Antisense and Its Effects on Embryonic Sensitivity to Heat Shock

Experiments were performed to evaluate the efficiency of inhibition of HSP70 gene expressionby antisense oligonucleotides complementary to the mRNA of HSP70 and to test the effects ofinhibition of HSP70 gene expression on subsequent embryonic sensitivity to heat shock. Theresults showed that transfection of pre-implantation embryos at 4-cell stage with 5 Mantisense oligo had no effect on in vitro blastocyst development. However, transfection with10 to 40 M antisense oligo had reduced in vitro blastocyst development to 15, 10% and 0; Forthe embryos which exposed to 40 M As arrested at the 16-cell stage, there was no blastocystformation within the heat shock groups. In contrast, transfection had no effect on embryonicsensitivity to heat shock, above 25% of embryos developed to blastocyst stage in controlgroups.

Effect of NHE1 antisense gene transfection on the biological behavior of SGC-7901 human gastric carcinoma cells

AIM: To study the effect of type 1 Na+/H+ exchanger (NHE1 ) antisense human gene transfection on the biological behavior of gastric carcinoma cell line SGC-7901. METHODS: Antisense NHE1 eukaryotic expression on vector pcDNA3.1 was constructed by recombinant DNA technique and transfected into gastric carcinoma cell line SGC-7901 with DOTAP liposome transfection method. Morphological changes of cells were observed with optic and electron microscopes. Changes in cell proliferative capacity, apoptosis, intracellular pH (pHi), cell cycle, clone formation in two-layer soft agar, and tumorigenicity in nude mice were examined. RESULTS: Antisense eukaryotic expressing vectors were successfully constructed and transfected into SGC-7901. The transfectant obtained named 7901 -antisense (7901-AS) stablely produced antisense NHE1. There was a significant difference between the pHi of 7901-AS cells (6.77 ± 0.05) and that of 7901-zeo cells and SGC-7901 cells (7.24 ± 0.03 and 7.26 ± 0.03, P < 0.01). Compared with SGC-7901 and 7901-zeo cells, 7901-AS cells mostly showed cell proliferation inhibition, G1/G0 phase arrest, increased cell apoptotic rate, recovery of contact inhibition, and density contact. The tumorigenicity in nude mice and cloning efficiency in the two-layer soft agar were clearly inhibited. CONCLUSION: NHE1 antisense gene significantly restrains the malignant behavior of human gastric carcinoma cells, suppresses cell growth and induces cell apoptosis, and partially reverses the malignant phenotypes of SGC-7901 . These results suggest a potential role for human tumor gene therapy.

Inhibiting effect of antisense oligonucleotides phosphorthioate on gene expression of TIMP-1 in rat liver fibrosis

AIM: To observe the inhibition of antisense oligonucleotides (asON) phosphorthioate to the tissue inhibitors metalloproteinase-1 (TIMP-1) gene and protein expression in the liver tissue of immunologically induced hepatic fibrosis rats. The possibility of reversing hepatic fibrosis through gene therapy was observed. METHODS: Human serum albumin (HSA) was used to attack rats, as hepatic fibrosis model, in which asONs were used to block the gene and protein expressing TIMP-1. According to the analysis of modulator, structure protein, coding series of TIMP-1 genome, we designed four different asONs. These asONs were injected into the hepatic fibrosis models through coccygeal vein. The results was observed by RT-PCR for measuring TIMP-1 mRNA expression, immunohistochemistry and in situ hybridization for collagen I, II, special staining of collagen fiber, and electron microscopic examination. RESULTS: Hepatic fibrosis could last within 363 days in our modified model. The expressing level of TIMP-1 was high during hepatic fibrosis process. It has been proved by the immunohistochemical and the electron microscopic examination that the asON phosphorthioate of TIMP-1 could exactly express in vivo. The effect of colchicine was demonstrated to inhibit the expressing level of mRNA and the content of collagen I, III in the liver of experimental hepatic fibrosis rats. However, the electron microscopy research and the pathologic grading of hepatic fibrosis showed that there was no significant difference between the treatment group and the model group (P】 0.05). CONCLUSION: The experimental rat model of hepatic fibrosis is one of the preferable models to estimate the curative effect of anti-hepatic fibrosis drugs. The asON phosphorthioate of TIMP-1 could block the gene and protein expression of TIMP-1 in the liver of experimental hepatic fibrosis rats at the mRNA level. It is possible to reverse hepatic fibrosis, and it is expected to study a new drug of antihepatic fibrosis on the genetic level. Colchicine has very limited therapeutic effect on hepatic fibrosis, furthermore, its toxicity and side effects are obvious.

Effect of VEGF-targeted antisense gene therapy on retinoblastoma cell line SO-RB50 in vitro and in vivo

AIM: To evaluate the possibility of generation 4 polyamidoamine (G4PAMAM) dendrimers acting as the delivery system of vascular endothelial growth factor (VEGF) antisense oligodeoxynucleotides (VEGFASODN), and to investigate the anti-tumor effect of G4PAMAM/VEGFASODN complex on the cultured cells and the mouse tumor xenograft model. METHODS: The transfection efficiency was assessed by Row cytometry (FCM). Thiazolyl tetrazolium (MU) assay was performed to determine the relative growth rate (RGR) of the cells after transfection. Then a mouse tumor xenograft model of human retinoblastoma was established. Different interventions were given to the mice by intratumoral injection and the tumor growth was monitored. The expression of VEGF mRNA was detected by reverse transcription PCR (RT-PCR), the expression of VEGF protein was determined by western blot analysis, and the microvessel density (MVD) was measured by immunohistochemistry (IHC) staining. RESULTS: G4PAMAM/VEGFASODN exhibited a high transfection rate in vitro, and the transfection rates of different doses of G4PAMAM/VEGFASODN groups increased with higher doses. This effect was accompanied by a dose-depended reduction in cell viability. The tumor growth in the tumor-bearing athymic mice was significantly inhibited in the G4PAMAM/VEGFASODN group. The expressions of VEGF mRNA and protein were obviously inhibited in the G4PAMAM/VEGFASODN group (p<0.05), and the MVD of the G4PAMAM/VEGFASODN group was lower than that of the other groups(p<0.05). CONCLUSION: VEGFASODN can be delivered into the cultured and transplanted retinoblastoma cells efficiently by G4PAMAM, suppress the expressions of VEGF mRNA and protein, and reduce the MVD of tumor tissues. The G4PAMAM/VEGFASODN complex has antitumor properties vitro and in vivo.

Anti-aging Effects of Alu Antisense RNA on Human Fibroblast Senescence Through the MEK-ERK Pathway Mediated by KIF15

Objective:To investigate whether human short interspersed nuclear element antisense RNA(Alu antisense RNA;Alu asRNA)could delay human fibroblast senescence and explore the underlying mechanisms.Methods:We transfected Alu asRNA into senescent human fibroblasts and used cell counting kit-8(CCK-8),reactive oxygen species(ROS),and senescence-associated beta-galactosidase(SA-β-gal)staining methods to analyze the anti-aging effects of Alu asRNA on the fibroblasts.We also used an RNA-sequencing(RNA-seq)method to investigate the Alu asRNA-specific mechanisms of anti-aging.We examined the effects of KIF15 on the anti-aging role induced by Alu asRNA.We also investigated the mechanisms underlying a KIF15-induced proliferation of senescent human fibroblasts.Results:The CCK-8,ROS and SA-β-gal results showed that Alu asRNA could delay fibroblast aging.RNA-seq showed 183 differentially expressed genes(DEGs)in Alu asRNA transfected fibroblasts compared with fibroblasts transfected with the calcium phosphate transfection(CPT)reagent.The KEGG analysis showed that the cell cycle pathway was significantly enriched in the DEGs in fibroblasts transfected with Alu asRNA compared with fibroblasts transfected with the CPT reagent.Notably,Alu asRNA promoted the KIF15 expression and activated the MEK-ERK signaling pathway.Conclusion:Our results suggest that Alu asRNA could promote senescent fibroblast proliferation via activation of the KIF15-mediated MEK-ERK signaling pathway.

Effect of the Antisense BcMF12 Driven by the BcA9 Promoter on Gene Silencing in Brassica campestris L.ssp.chinensis

The study analyzed the silencing of BcMF12 gene regulated by BcA9 promoter in the transgenic pakchoi and confirmed the effect of antisense BcMF12 gene on the pollen development. A conserved BcMF12 gene fragment was amplified from the cDNA of flower buds in pakchoi （Brassica campestris L. ssp. chinensis, syn. B. rapa L. ssp. chinensis） and was fused to the anther specific BcA9 promoter. The plant antisense expression vector was constructed and then introduced into pakchoi via Agrobacterium-mediated transformation. The transgenic plants were screened by antibiotics and molecular analysis. PCR and Southern blot revealed that the antisense BcMF12-GUS fusion gene regulated by BcA9 promoter was integrated into transgenic plants. Northern blot suggested that the expression of BcMF12 gene was down-regulated significantly. The pollen germination rate of transgenic plants with antisense BcMF12 gene decreased as compared with that of the control plants. The expression of the gene BcMF12 related to the pollen development was inhibited by the antisense BcMF12 driven by BcA9 promoter, which consequently affected the pollen development in pakchoi.

Altered Oncogene Activity Contributes to Compensation for Antisense Suppression of Bcl-2 and Tumor Resistance

Antisense oligonucleotides (oligos) have targeted growth regulatory proteins in prostate cancer models. To identify compensatory alterations in the expression of non-targeted genes we evaluate mono- and bispecific oligos targeting and equally suppressing the expression of the apoptosis inhibitory protein bcl-2. Bcl-2 is chosen because oligos directed towards it have entered clinical trials to restore apoptosis in cancer patients. Treated LNCaP cells compensate for the diminished bcl-2 by suppressing caspase-3 (an apoptosis promoter) while enhancing expression of AKT-1 (another apoptosis inhibitor), androgen receptor (AR) and its (p300 and IL-6) coactivators. Additional proteins are enhanced including PD-1, its ligand PD-L1 (immune checkpoint blockade markers) and fas-ligand, which activate apoptosis through the signal transduction, along with suppressor protein p53, polymerase transcription mediator MED-12 and signal transducer STAT-3. These alterations in expression may contribute to a greatly enhanced expression of the proliferation marker KI-67. This suggests that therapeutic approaches to restore apoptosis through suppression of bcl-2 lead to an altered expression in non-targeted genes involving apoptosis, androgen sensitivity, transcriptional activity and immune responsiveness, leads to an increase in proliferation (and a more androgen driven aggressive phenotype). In this study we evaluate the expression of two oncogenes (v-myc and K-ras) and find a large and significant enhancement of v-myc activity, which is produced by oligos targeting bcl-2 at the 5’ position. For K-ras, although significant suppression is produced by the bispecific targeting bcl-2 at the 3’ position, the percent change is relatively small compared with other compensatory alterations we have measured, and much less than in v-myc. Therefore, for the two oncogenes being evaluated, only increased v-myc activity is probably large enough to contribute to increased tumor aggressiveness in compensation for bcl-2 suppression.

Immunotherapy of Malignant Tumors Using Antisense Anti-IGF-I Approach: Case of Glioblastoma

The review article describes the criteria established for methodology of antisense anti IGF-I therapy of malignant tumors, particularly of glioblastoma. The cancer patients, after classical therapy of surgery, radiotherapy and chemotherapy, have undergone the injection of genetically modified autologous malignant cells—transfected by IGF-I antisense/triple helix expression vectors. For all cancer patients supervised for up to 19 months, the period corresponding to minimum survival of glioblastoma patients, the following common immune criteria for “anti IGF-I” strategy were admitted: 1) characteristics of cell “vaccines”—absence of IGF-I and expression of MHC-I in cloned transfected cells;2) the peripheral blood lymphocytes, PBL cells, removed after every of two successive vaccinations, demonstrate an increasing level of CD8+ and CD8+28+ molecules (with a switch from CD8+11b+ to CD8+11b-).

The effects of antisense PTEN gene transfection on the growth and invasion of glioma cells

Objective:To study the effects of antisense PTEN gene on the growth and invasion of glioma cells. Methods:A pcDNA3. 1/Hygro (-) recombinant plasmid containing antisense PTEN gene fragment was constructed. Glioma cells of primary culture were transfected with antisense PTEN gene vector and stably transfected clones were selected. Then, the different growth and invasion abilities and the different MMP9 mRNA expressions of three kinds of cells were observed, including the transfected cells, untransfected cells and the cells transfected with empty vector. Results :The abilities of growth and invasion of the transfected cells and the expressions of MMP9 mRNA were obviously enhanced. Conclusion: Antisense PTEN gene could have a negative impact on the growth and invasion of primary culture glioma cells.

Effect of antisense DNMT3b gene eukaryotic expression plasmid on expression of the DNMT3b gene in human biliary tract carcinoma cells

BACKGROUND: Hypermethylation of the promoter region is one of the major mechanisms of tumor suppressor gene inactivation. DNA methyltransferase 3b (DNMT3b), an enzyme that participates in the establishment of de novo methylation patterns, is highly expressed in many tumor cells and tissues, and it is closely associated with hypermethylation of the promoter of tumor suppressor genes. The aim of this study was to explore the effect of transfection with antisense DNMT3b gene eukaryotic expression plasmid on the expression of the DNMT3b gene in human biliary tract carcinoma cell. METHODS: The constructed antisense DNMT3b gene eukaryotic expression plasmid was transfected into the human biliary tract carcinoma cell line QBC-939 with lipofectamine transfection reagent, and positive cell clones were formed using G418 selection after transfection. The constructed recombinant plasmid was transfected into QBC-939 cells successfully and was confirmed by amplification of the exogenous neo^R gene with the polymerase chain reaction method. The expression of DNMT3b gene mRNA and protein was detected by semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) and flow cytometry respectively. RESULTS: Following transfection, the mRNA level of the DNMT3b gene decreased from 0.956±0.053 to 0.209±0.023, and the protein level of the DNMT3b gene also decreased from (75.38±3.22)% to (29.87±3.46)%. Very significant differences were observed both at the transcription and posttranscription levels in the expression of the DNMT3b gene between the non-tranfection group and the antisense DN- MT3b gene eukaryotic expression plasmid transfection group (P<0.01). CONCLUSIONS: Transfection with the antisense DNMT3b gene eukaryotic expression plasmid can significantly reduce the expression level of the DNMT3b gene in the human biliary tract carcinoma cell line QBC-939. This study may provide a valid method to investigate the function of the DNMT3b gene and its role in biliary tract carcinoma.

EXPERIMENTAL STUDY ON THE GENE THERAPY OF MALIGNANT GLIOMA WITH ANTISENSE VEGF RNA

Objective: To study the effect of antisense VEGF RNA on rat C6 gliomas in vivo and find out the feasibility ofantiangiogenesis therapy with antisense VEGF RNA formalignant gliomas. Methods: Parental rat C6 glioma cells and C6 cells transfected with antisense VEGF cDNA were implanted intracerebrally and subcutaneously into SD rats as control and transfected group. Rats bearing cerebral and subcutaneous C6 gliomas were treated with antisenseVEGF cDNA as treated group and sense VEGF cDNA and empty vector as control of treated group. The generalmanifestation, survival time, MRI and histopathologicalchanges of all rats were observed. The volume ofsubcutaneously implanted tumors was determinedregularly. In situ hybridization and immunohistochemicalstaining were used for detection of VEGF gene expression of gliomas while PCNA immunostaining and TUNELmethod for examination of proliferation activity andapoptosis of gliomas, respectively. Results: The survival of the rats in transfected and treated group was prolonged.There were two rats surviving over 90 d in the treatedgroup and their tumors disappeared. The VEGF geneexpression, the number of microvessels and theproliferation activity were decreased and a large amount of apoptotic cells could be found in cerebral and subcutaneous gliomas in treated and transfected groups. Conclusion:VEGF is one of the candidate genes for gene therapy ofmalignant gliomas. Antisense VEGF RNA combined with other therapies should be studied further for enhancing the therapeutic effect of malignant gliomas.

EXPRESSION OF c－myc GENE AND BIOSYNTHESIS OF BIOLOGICAL MACROMOLECULES IN ANTISENSE TRANSFECTANT HL_（60）~R－9

The recombinant plasmid PGC was constructed for transcription unit of c-myc gene with diorientation in vitro, to make RNA probes for detection of c-myc mRNA and antisence RNA expression of tranfectant HL-9,which was obtained from HL60 cells transfected with inducible c-myc antisense RNA expression plasmid. The results from HL-9 cells induced by Cd2+ indicated that expression of c-myc antisense RNA increased with Cd2+ concentration and exposure time, while c-myc mRNA expression progressively reduced. Using immunohistochemical technique no c-myc P62 protein expression was detected. The incorporation of 3H-TdR, 3H-UR and 3H-Leu revealed significant suppression of DNA, RNA and protein biosynthesis. It is suggested that the reversion changes previously reported in malignant Phenotypes of HL-9 cells and the inhibition of macromolecular biosynthesis mentioned above were associated with the blockade of c-myc gene expression by its antisense RNA.

Effect of Antisense MBD1 Gene Eukaryotic Expression Plasmid on Expression of MBD1 Gene in Human Biliary Tract Carcinoma Cells

Hypermethylation of the promoter region is one of the major mechanism of tumor suppressor gene inactivation. In order to provide a research tool for the study on the function of MBD1 gene in DNA methylation and tumorigenesis, antisense MBD1 gene eukaryotic expression plasmid was constructed and transfected into human biliary tract carcinoma cell line QBC-939 to observe its effect on the expression of MBD1 mRNA and protein by using RT-PCR and FCM respectively. Following the transfection, the mRNA level of MBD1 gene decreased from 0. 912±0.022 to 0. 215±0. 017, and the protein level of MBD1 gene also decreased from （80.19±5.05） %to （35.11±4.05） %. There were very significant differences in the expression both at the transcription and post-transcription levels of MBD1 gene between non-tranfection group and the antisense MBD1 gene eukaryotic expression plasmid transfection group （P〈0.01）. It was suggested that transfection with the antisense MBD1 gene eukaryotic expression plasmid can significantly reduce the expression level of MBD1 gene in QBC-939, and this study may provide a valid tool for the investigation of the function of MBD1 gene and its role in biliary tract carcinoma.

Construction of the Antisense Eukaryotic Vector for Proliferating Cell Nuclear Antigen Gene and Its Expression in Bladder Cancer EJ Cell Line

To explore a novel strategy for antisense gene therapy of cancer,the coding sequence of hum an proliferating cell nuclear antigen(PCNA) c DNA was reversely inserted into the eukaryotic vector p L XSN by molecular cloning techniques and transferred into bladder cancer EJcells with li- posome. The PCNA expression in transferred cells was dynamically detected by immunofluo- rescence and RT- PCR techniques. Changes of proliferation activities of cancer cells were assayed by MTT colorim etric and cloning formation m ethods.In the experiment,the antisense eukaryotic vector was successfully constructed and nam ed as p L APSN.After transfection with it for1- 7 days,PCNA protein and m RNA levels in cancer cells were blocked by16 .74 % - 84 .2 1% (P< 0 .0 5 ) and2 3.2 7% - 86 .15 % (P<0 .0 5 ) respectively.The proliferation activities of transferred cells were inhibited by 2 7.91% - 6 2 .0 7% (P<0 .0 1) ,with cloning formation abilities being de- creased by 5 0 .81% (P<0 .0 1) . Itwas concluded that the in vitro proliferation activities of cancer cells could be effectively inhibited by blocking PCNA expression with antisense technique,which could serve as an ideal strategy for gene therapy of bladder cancer.

Effect of adenoviral vector-mediated rat antisense AT1B gene transfer on neointima proliferation after rat carotid injury

Objective: Angiotensin Ⅱ is a growth-promoting factor for vascular smooth muscle cells in culture andin the intact animal. The biological effects of angiotensin Ⅱ are manifested only by binding to specific receptors oncell membranes. In the study, we observed that the effect of rat antisense AT1B gene transfer mediated by adenoviral vector-on neointimal proliferation following rat carotid injury. Methods: Antisense AT1B gene was transductedinto the carotid by adenoviral vector after carotid bal1oon injury and the restenosis model was established in SD rat.We measured neointima/media area ratio in local artery at day 21 after gene transfer. Results: Rat antisense AT1Bgene was successfully transducted into local carotid after the carotid balloon injury. Neointima/media area ratiowas significantly reduced (47 %, P<0. 01) at day 21 after gene transfer compared with the control group. Conclusion: The results suggest it is possible that antisense AT1B gene transfer as a potential therapeutic approach prevent neointimal hyperplasia.

Inhibitory effects of PIN1 antisense gene on the proliferation of human osteosarcoma cells

Objective： To evaluate the inhibitory effects of PIN1 antiseuse gene on the proliferation of htnnan osteosarcoma cells. Methods： Different doses of antisense PIN1 gene （0,20,50,100,200,250μl） were transfected into osteosarcoma MG-63 cells. The cells and the culture supernatants before and after transfection were collected. The cell growth curve was made using MTT method. The cell growth cycle and apoptosis were detected by FCM. The expression of PIN1 was detected by Western blot. The expression of PIN1 mRNA was detected by reverse transcription polymerase chain reaction （RT-PCR）. Results： MTT and FCM assays indicated that the transfection of antisense PIN1 gene could inhibit profiferation of MG-63 cells and lead to cell apoptosis. Western-blot assays revealed the MG-63 cells transfected with antisense PIN1 gene had weaker expression than those without transfection with antisense PIN1 gene, and the band intensity was negatively related with doses. The cells transfected with different doses of gene （0,20,50,100,200,250μl） had different absobance rate（0.854±0.136,0.866±0.138,0.732±0.154,0.611 ± 0.121, 0. 547 ± 0. 109, 0. 398 ± 0.113, 0. 320 ± 0.151）, with significant difference assessed by F and q test （P〈0.05）. The absorbance rate of PINI mRNA was 0.983±0.125,0.988±0.127, 0.915±0.157, 0.786 ± 0.125,0.608 ± 0.124,0.433 ± 0.130,0.410 ± 0. 158 respectively （ P 〈 0.05）. Conclusion. The expression of PIN1 mRNA in MG-63 cells could be inhibited by antiseuse PIN1 gene, and then the expression of PIN1 was reduced and depressed, and so the proliferation of hmnan osteosarcoma cells MG-63 was inhibited.

Inhibition of α_1(Ⅰ) collagen gene in vitro transcription by antisense oligodeoxynucleotides

Objective and Methods: Excessive accumulation of collagen typeⅠ and type Ⅲ causes the formation of keloids and hypertrophic scars. To understand the mechanism by which antisense oligodeoxynucleotide (Oligo) acts on in vitro transcrption α1 (I) collagen gene, isotopes (α-32pGTP) was incorporated into 2 SP6 in vitro transcription systems. Results and Conclu- sion: Oligo 2 (at the transcription start region) could effectively inhibit in vitro transcription of pGEM3-Col13 and the control (random oligodeoxynucleotides) showed no inhibition. However, oligo 1 (at the transcription start region) obviously inhibited the in vitro transcription of pGEM3-Col14, while Oligo 2, which targeted at the down stream region (about 200 bp) of the promoter showed no significant inhibition effect.