• Bulletin of the Korean Chemical Society
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• 제34권3호
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• pp.735-742
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• 2013

Peptide nucleic acids (PNAs) that bind to complementary nucleic acid sequences with extraordinarily high affinity and sequence specificity can be used as antisense oligonucleotides against microRNAs, namely antagomir PNAs. However, methods for efficient cellular delivery must be developed for effective use of PNAs as therapeutic agents. Here, we demonstrate that antagomir PNAs can be delivered to hepatic cells by complementary DNA oligonucleotide and cationic liposomes containing galactosylated ceramide and a novel cationic lipid, DMKE (O,O'-dimyristyl-N-lysyl glutamate), through glycoprotein-mediated endocytosis. An antagomir PNA was designed to target miR-122, which is required for translation of the hepatitis C virus (HCV) genome in hepatocytes, and was hybridized to a DNA oligonucleotide for complexation with cationic liposome. The PNA-DNA hybrid molecules were efficiently internalized into hepatic cells by complexing with the galactosylated cationic liposome in vitro. Galactosylation of liposome significantly enhanced both lipoplex cell binding and PNA delivery to the hepatic cells. After 4-h incubation with galactosylated lipoplexes, PNAs were efficiently delivered into hepatic cells and HCV genome translation was suppressed more than 70% through sequestration of miR-122 in cytoplasm. PNAs were readily released from the PNA-DNA hybrid in the low pH environment of the endosome. The present study indicates that transfection of PNA-DNA hybrid molecules using galactosylated cationic liposomes can be used as an efficient non-viral carrier for antagomir PNAs targeted to hepatocytes.

• Asian Pacific Journal of Cancer Prevention
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• 제15권2호
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• pp.629-635
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• 2014

Background: Acute myeloid leukemia (AML) is a fatal hematological malignancy which is resistant to a variety of chemotherapy drugs. Myeloid cell leukemia-1 (Mcl-1), a death-inhibiting protein that regulates apoptosis, has been shown to be overexpressed in numerous malignancies. In addition, it has been demonstrated that the expression level of the Mcl-1 gene increases at the time of leukemic relapse following chemotherapy. The aim of this study was to target Mcl-1 by small interference RNA (siRNA) and analyze its effects on survival and chemosensitivity of acute myeloid leukemia cell line HL-60. Materials and Methods: siRNA transfection was performed with a liposome approach. The expression levels of mRNA and protein were measured by real-time quantitative PCR and Western blot analysis, respectively. Trypan blue assays were performed to evaluate tumor cell growth after siRNA transfection. The cytotoxic effects of Mcl-1 siRNA (siMcl-1) and etoposide were determined using MTT assay on their own and in combination. Apoptosis was quantified using a DNA-histone ELISA assay. Results: Transfection with siMcl-1 significantly suppressed the expression of Mcl-1 mRNA and protein in a time-dependent manner, resulting in strong growth inhibition and spontaneous apoptosis. Surprisingly, pretreatment with siMcl-1 synergistically enhanced the cytotoxic effect of etoposide. Furthermore, Mcl-1 down-regulation significantly increased apoptosis sensitivity to etoposide. No significant biological effects were observed with negative control siRNA treatment. Conclusions: Our results suggest that specific suppression of Mcl-1 by siRNA can effectively induce apoptosis and overcome chemoresistance of leukemic cells. Therefore, siMcl-1 may be a potent adjuvant in leukemia chemotherapy.

• Asian Pacific Journal of Cancer Prevention
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• 제13권6호
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• pp.2837-2840
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• 2012

We investigated whether IFN-${\beta}$ inhibits the growth of human malignant glioma and induces glioma cell apoptosis using the human IFN-${\beta}$ gene transfected into glioma cells. A eukaryonic expression vector ($pSV2IFN{\beta}$) for IFN-${\beta}$ was transfected into the glioma cell line SHG44 using liposome transfection. Stable transfection and IFN-${\beta}$ expression were confirmed using an enzyme-linked immunosorbent assay (ELISA). Cell apoptosis was also assessed by Hoechst staining and electron microscopy. In vivo experiments were used to establish a SHG44 glioma model in nude mice. Liposomes containing the human IFN-${\beta}$ gene were injected into the SHG44 glioma of nude mice to observe glioma growth and calculate tumor size. Fas expression was evaluated using immunohistochemistry. The IFN-${\beta}$ gene was successfully transfected and expressed in the SHG44 glioma cells in vitro. A significant difference in the number of apoptotic cells was observed between transfected and non-transfected cells. Glioma growth in nude mice was inhibited in vivo, with significant induction of apoptosis. Fas expression was also elevated. The IFN-${\beta}$ gene induces apoptosis in glioma cells, possibly through upregulation of Fas. The IFN-${\beta}$ gene modulation in the Fas pathway and apoptosis in glioma cells may be important for the treatment of gliomas.

• Asian-Australasian Journal of Animal Sciences
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• 제15권10호
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• pp.1412-1421
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• 2002

To examine the feasibility of using a sperm vector system for gene transfer, we have investigated the binding and the uptaking of foreign DNA into the sperm nucleus by PCR, in situ hybridization and LSC. We have also examined the transportation of exogenous DNA into oocytes by immunofluorescene via PCR. Sperm cells were incubated with DNA/liposome complexes (1:4 ratio) in fertilization medium with BSA or without BSA. In situ hybridization demonstrated that the transfection rate of sperm cells with and without BSA was 41 and 68% respectively, when the cells were treated with liposome/DNA complexes and 13% for DNA alone. LSC analysis showed that the binding of exogenous DNA was greatly reduced by DNase I treatment which digests DNA bound onto spermatozoa, suggesting that some of the DNA was internalized into the sperm membrane. To find out whether transfected DNA was internalized into sperm intracytomembrane, sperm DNA was amplified by inverse PCR. No PCR products were detected from sperm cells, indicating that the foreign DNA was simply bound onto the sperm membrane. To investigate transfer rates of exogenous DNA into oocytes via sperm cells, we used immunofluorescene method to follow the distribution of foreign DNA via spermatozoa: a few exogenous DNA was located in the cytoplasm of early embryos (13/60, 21.7% for DNA+/liposome+/BSA) and was not located in the pronucleus and/or nucleus. These results suggest that most of the transfected sperm cells could carry the foreign DNA into the egg by in vitro fertilization, but that the transferred DNA is degraded in the developing embryos without stable integration into the zygote genome. Therefore, we have directly injected with transfected sperm cell into oocyte cytoplasm and observed that some of the exogenous DNA was detected in preimplantation embryonic cytoplasm and expressed at preimplantation stages, suggesting that exogenous DNA in early zygote has their integrity. In this study, we have not identified a noble mechanism that interfering transportation of foreign DNA into zygote genome via spermatozoa. Our data, however, demonstrated that inverse PCR and immunofluorescene methods would be used as a new tool for follow-up of gene distribution in oocyte via sperm cells.

• Reproductive and Developmental Biology
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• 제28권1호
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• pp.71-76
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• 2004

Gene delivery is one of the keen interests in animal industry as well as research on gene functions. Some of the in vivo gene delivery techniques have been successively used in various tissues for the gene therapy and transgenesis. Despite intensive efforts, it still remains to overcome problems of limited local and regional administration and low transgene expression. To improve the efficiency of gene delivery, a new procedure was tested. We injected exogenous DNA containing LacZ into the female or male gonads and then pulsed electric field. Electroporated gonads showed positive X-gal staining in many seminiferous tubules of the porcine fetal gonads. Exogenously introduced LacZ genes were also expressed in female porcine gonad. In addition, we demonstrated efficient gene delivery in gonad of adult mouse. Furthermore, we succeed to generate genetically modified germline cells showing GFP and positive X-gal signals. The results suggest that the newly developed gene delivery is an effective way of in vivo transfection in mammals. The developed gene delivery procedure should be useful in producing transgenic animals when combined with primary cell culture and nuclear transplantation.

• Nuclear Medicine and Molecular Imaging
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• 제41권3호
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• pp.209-217
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• 2007

목적: mdr1유전자를 표적으로 한 short hairpin RNA (shMDR)는 다약재내성을 나타내는 암세포에서 효과적으로 mdr1 유전자의 발현을 억제 할 수 있고 sodium iodide symporter (NIS)는 유전자 치료와 리포터로의 기능을 동시에 나타낼 수 있다. 이 연구에서는 사람 대장암세포(HCT15)에 shMDR과 NIS를 동시에 이입하고 Tc-99m sestamibi와 I-125 섭취를 측정하였고 doxorubicin과 I-131 치료효과도 관찰하였다. 대상 및 방법: 사람 태아 신장 세포주(Human Embryonic Kidney cells; HEK293)에 liposome 시약으로 shMDR을 이입하고 RT-PCR과 western blot으로 분석하였다. shMDR와 NIS 유전자가 발현하는 adenovirus를 만들고 HCT15 세포에 이입 후 48시간에 shMDR에 의한 Pgp의 기능 억제를 확인하기위해 Tc-99m sestamibi 섭취와 doxorubicin 세포독성을 측정하였다. 또한 NIS유전자의 기능을 확인 하기위해 I-125 섭취와 I-131 세포독성도 확인하였다. 결과: shMDR이 이입 된 HEK293 세포에서 mdr1의 mRNA와 Pgp의 발현이 각각 75%, 80% 감소하였다. NIS 유전자가 발현하는 adenovirus를 HCT15 세포에 이입하고 NIS 유전자 발현을 확인 한 결과 대조군에 비해 월등히 높게 발현하였다. Ad-shMDR 300 MOI, Ad-shMDR 300 MOI 와 Ad-NIS 10 MOI를 처리한 경우 Tc-99m sestamibi의 섭취가 대조군보다 1.5배 정도 증가하였다. HCT15 세포에 Ad-NIS 10 MOI를 감염시킨 경우 I-125 섭취가 대조군에 비해 25배 이상 증가였다. 또한 Ad-shMDR와 Ad-NIS를 동시 감염 시켰을 경우 doxorubicin의 세포 독성이 증가하여 나타났고 Ad-NIS 20 MOI를 감염시켰을 때 I-131에 의한 세포독성이 대조군보다 증가하였다. 결론: 세포에 shMDR의 이입으로 mdr1 유전자의 발현이 억제되고 Tc-99m sestamibi의 섭취와 doxorubicin의 세포독성이 증가하였으며 NIS 유전자의 이입으로 I-125의 섭취와 I-131의 세포독성이 증가하였다. 다약제내성세포에 shMDR와 NIS 유전자의 동시 이입은 doxorubicin과 방사성 옥소의 이중치료 효과를 높일 수 있을 것으로 본다.

• 한국가금학회지
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• 제23권2호
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• pp.61-69
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• 1996

Primordial germ cells (PGCs) were manipulated as part of the system to produce transgenic chickens. PGCs were isolated from the germinal crescent of developmental stage 6 to 8 donor emhryos of the Korean Native Ogol Chickens (KNOC). These PGCs were transfected with plasmid DNA containing the lac Z gene by liposome mediated transfection methods. The lac Z gene was transfected and expressed in the PGCs. These transfected PGCs were injected into the germinal crescent of White Leghorn embryos (stage 6 to 8). The injected transfected PGCs migrated via the circulatory system into the future gonad and expression observed in the gonads of 3 day old chick. Of the 47 embryos and 3 day old chickens, one positive PGCs gonad from sacrificed young chickens was detected by appearance of blue cells. Plasmid DNA with the foreign gene was incorporated into the population of germ cells in the gonad. These results demonstrate that PGCs can he transfected and then transferred for colonization into the gonad, and show the potential to ultimately manipulate the genetic material of the chicken gernline.

• Asian Pacific Journal of Cancer Prevention
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• 제13권6호
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• pp.2799-2806
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• 2012

The aim of this study was to elucidate the role of the integrin-linked kinase (ILK) gene in development of human bladder transitional cell carcinoma (BTCC). Expression of ILK protein and ILK mRNA in 56 cases of human BTCC tissue and in 30 cases of adjacent normal bladder tissue was detected by immunohistochemistry S-P and reverse transcription polymerase chain reaction (RT-PCR), respectively. Four specific miRNA RNAi vectors targeting human ILK were synthesized and transfected into BIU-87 cells by liposome to obtain stable expression cell strains. The influence of ILK on proliferation of BTCC was detected by MTT, FCM on athymic mouse tumorigenesis. The positive rate of ILK protein in BTCC tissue (53.6%) was much higher than adjacent normal bladder tissue (10.0%) (p<0.05). Similarly, expression of ILK mRNA in BTCC tissue ($0.540{\pm}0.083$) was significantly higher than in adjacent normal bladder tissue ($0.492{\pm}0.070$) (p<0.05). MTT showed that the proliferation ability of miRNA-ILK transfected group was clearly decreased (p<0.05), the cell cycle being arrested in G0/G1-S, an tumorigenesis in vivo was also significantly reduced (p<0.05). ILK gene transcription and protein expression may be involved in the development of BTCC, so that ILK might be the new marker for early diagnosis and the new target for gene treatment.

• Nuclear Medicine and Molecular Imaging
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• 제42권5호
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• pp.383-393
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• 2008

목적: 조직 특이 프로모터를 이용하면 특정 암조직내에서만 원하는 치료유전자를 발현시킬 수 있다. 나트륨 옥소 공동 수송체(sodium iodide symporter: NIS) 유전자는 옥소를 섭취하는 특성을 가져 방사성옥소를 이용한 치료용 유전자로 사용될 수 있다. 광학 영상용 유전자인 luciferase (Luc) 유전자를 세포에 이입하면 비침습적으로 유전자가 이입된 세포의 상태를 평가할 수 있다. 본 연구는 간암 특이성을 나타내는 AFP 프로모터에 의해 발현이 조절되는 NIS유전자와 CMV프로모터에 의해 발현되는 Luc유전자를 간암세포에 이입하여 NIS유전자 이입에 의한 방사성옥소 유전자치료의 효과를 알아보고, 종양사멸 정도를 광학 리포터 유전자 발현으로 알아보고자 하였다. 대상 및 방법: AFP enhancer와 GSTP 프로모터를 연결하여 AFP프로모터를 제작하였으며 이를 NIS유전자와 연결하였다. 또한 CMV 프로모터에 조절 받는 Luc 유전자를 동시에 삽입하여 AFP-NIS-CMV-Luc 유전자 발현 벡터를 생산하였다. 실험 대상 세포주로는 간암세포주인 HepG2와 Huh-7 세포와 사람 대장암세포주인 HCT-15 세포를 이용하였다. AFP-NIS-CMV-Luc 발현벡터를 Liposome을 이용해 실험대상 세포주 내로 이입하였으며, 방사성옥소 섭취율과 방사성옥소의 유출량을 측정하였다. 또한 Luciferase 발현 정도를 luminometer로 측정하였으며, clonogenic assay를 통하여 I-131에 대한 세포주에 따른 사멸효과 차이를 알아보았다. AFP-NIS-CMV-Luc 유전자 이입 세포주를 누드마우스에 대퇴부 피하에 주입하여 I-131 축적여부를 감마카메라 영상을 획득하였다. 결과: AFP-NIS-CMV-Luc 유전자 발현 벡터를 제작하였다. AFP-NIS-CMV-Luc 유전자가 이입된 HepG2와 Huh-7 세포의 방사성옥소 섭취율은 유전자 이입이 되지 않은 대조군 HepG2와 Huh-7 세포에 비하여 높았으며, $KClO_4$를 처리시 옥소 섭취가 저해되었다. 대장암 세포주인 HCT-15세포에 AFP-NIS-CMV-Luc유전자를 이입 시 방사성옥소의 섭취률은 증가되지 않았다. 30분간 방사성옥소를 섭취시킨 AFP-NIS-Luc 유전자가 이입된 HepG2와 Huh-7 세포에서의 방사성옥소의 유출반감기는 약 4분과 6분으로 각각 나타났다. AFP-NIS-CMV-Luc 유전자가 이입된 HepG2, Huh-7세포의 Luc 유전자의 발현은 241, 441 $RLU/2\;{\times}\;10^5$ cells로 나타났으며, 대조군 HepG2와 Huh구세포에서의 Luc 유전자의 발현은 74, $RLU/2\;{\times}\;10^5$ cells로 나타났다. HCT-15 세포는 AFP-NIS-CMV-Luc 유전자 이입에 따라 I-131에 의한 세포 사멸능이 증가되지 않았으나, HepG2 및 Huh-7 세포는 FP-NIS-CMV-Luc 유전자 이 입에 따라 I-131에 의한 세포 사멸능이 증가되었으며, Huh-7세포의 경우 0.5mCi의 I-131을 투여한 경우 모든 세포가 사멸하였다. AFP-NIS-CMV-Luc 유전자가 이입된 Huh-7 세포수가 많을수록 방사성옥소 섭취율이 증가하며 luciferase활성도도 높게 나타났다. AFP-NIS-CMV-Luc 유전자가 이입된 Huh-7 세포를 이식한 누드마우스에 I-131 감마카메라 영상에서 종양이식부위에 방사능 축적을 관찰 할 수 있었다. 결론: AFP프로모터의 의하여 NIS유전자가 발현되며, CMV프로모터에 의한 Luc 유전자가 발현되는 벡터를 제작하였으며, 이 벡터를 이입한 경우 간암세포에서만 I-131의 세포 독성이 증가하는 효과를 나타내었다. 또한 Luc유전자를 이용하여 비침습적인 광학 영상으로 세포사멸 효과를 확인할 수 있었다. 간암특이 프로모터에 조절되는 치료 유전자와 광학리포터 유전자를 한 벡터에 동시에 이입하면 간암 특이 유전자 치료와 그 치료효과를 비침습적으로 평가할 수 있을 것으로 생각된다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권12호
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• pp.6517-6521
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• 2012

To analyze the growth, proliferation, apoptosis, invasiveness and chemotherapy sensitivity of EC9706 cells after K-Ras gene silencing, an expression carrier pSilencer-siK-Ras was constructed, and the EC9706 cell line was transfected using a liposome technique. Six groups were established: Control, siRNA NC (transfected with empty vector pSilencer2.1); Ras siRNA (transfected with pSilencer-siK-Ras2); Paclitaxel; Paclitaxel + siRNA NC; and Ras siRNA + Paclitaxel. After the treatment, RT-PCR, Western blotting, MTT assay, flow cytometry and the Transwell technique were used to assess expression of K-Ras mRNA and protein in EC9706 cells, as well as cell growth, proliferation, apoptosis and invasiveness. The effect of Paclitaxel chemotherapy was also tested. pSilencer-siK-Ras2 effectively down-regulated expression of K-Ras mRNA and protein in EC9706 cells, growth being significantly inhibited. Flow cytometry indicated obvious apoptosis of cells in the experimental group, with arrest in the G1 phase; cell migration ability was also reduced. After pSilencer-siK-Ras2 transfection or the addition of Paclitaxel, EC9706 cells were suppressed to different extents; the suppressive effect was strengthened by combined treatment. The results suggested that RNAi-induced K-Ras gene silencing could enhance chemotherapy sensitivity of esophageal cancer.