• Title, Summary, Keyword: siRNA

검색결과 518건 처리시간 0.036초

Stem-loop RT-qPCR 분석법을 이용한 siRNA 치료제의 생체시료 분석법 검증 및 약물 동태학적 분석 (Validation of Stem-loop RT-qPCR Method on the Pharmacokinetic Analysis of siRNA Therapeutics)

  • 김혜정;김택민;김홍중;정헌순;이승호
    • 생명과학회지
    • /
    • v.29 no.6
    • /
    • pp.653-661
    • /
    • 2019
  • 본 연구는 siRNA 기반 치료제등의 핵산치료제 개발에 있어서 필수적인 약물의 생체내 흡수, 분포, 대사, 배설에 대한 동태의 확인을 위해 stem-loop RT-qPCR 법을 이용하여 보다 더 정확한 시험법을 확립하고자 하였다. siRNA에 특이적인 primer와 probe를 선별하여 siRNA 정량검출 시험법을 최적화하였다. siRNA 표준시료를 이용하여 최적화된 시험법을 적용하였을 때 siRNA 표준시료에 대한 Cp 값(y)간의 선형분석 결과, 기울기 평균 -3.3, 결정계수 $R^2$>0.99으로 확인되어 siRNA 표준시료와 Cp 값 간의 회귀성이 매우 높아 정량 분석이 가능한 시험법임을 확인하였고, 같은 표준시료를 이용한 stem-loop RT-qPCR의 검출한계(LOD)는 10 fM, 최소정량한계(LLOQ)는 100 fM이었다. 확립된 시험법의 신뢰성을 확인하기 위해 시험자를 다르게 하고, 시험법을 3회 반복하여 각각 진행한 결과, siRNA 표준시료에 대한 Cp 값(y)간의 선형분석 결과 기울기와 결정계수 $R^2$의 재현성(slope ${\pm}-3.2$, 결정계수 $R^2$>0.99)을 확인하였고, 표준 곡선으로부터 환산된 siRNA 표준시료의 회수율(recovery ${\pm}20%$)과 완건성이 우수함을 확인하였다. 확립된 stem-loop RT-qPCR을 생체내 존재하는 약물 검증에 적용할 수 있는지 확인하기 위하여 시험동물에 siRNA를 주입 후 시간별 혈액을 채취하여 확립된 시험법으로 시험을 진행하였고 약물 동태학적 분석을 통해 siRNA치료제의 혈액내의 안정성을 확인하였다. 따라서 본연구에서 개발된 stem-loop RT-qPCR 분석법은 정확성, 정밀성 및 민감도가 높은 분석법으로 핵산치료제 개발 연구의 다양한 생체시료 분석 연구에 적용할 수 있을 것으로 기대한다.

siRNA-mediated gene silencing of MexB from the MexA-MexB-OprM efflux pump in Pseudomonas aeruginosa

  • Gong, Feng-Yun;Zhang, Ding-Yu;Zhang, Jiang-Guo;Wang, Li-Li;Zhan, Wei-Li;Qi, Jun-Ying;Song, Jian-Xin
    • BMB Reports
    • /
    • v.47 no.4
    • /
    • pp.203-208
    • /
    • 2014
  • To gain insights into the effect of MexB gene under the short interfering RNA (siRNA), we synthesized 21 bp siRNA duplexes against the MexB gene. RT-PCR was performed to determine whether the siRNA inhibited the expression of MexB mRNA. Changes in antibiotic susceptibility in response to siRNA were measured by the E-test method. The efficacy of siRNAs was determined in a murine model of chronic P. aeruginosa lung infection. MexB-siRNAs inhibited both mRNA expression and the activity of P. aeruginosa in vitro. In vivo, siRNA was effective in reducing the bacterial load in the model of chronic lung infection and the P. aeruginosa-induced pathological changes. MexB-siRNA treatment enhanced the production of inflammatory cytokines in the early infection stage (P < 0.05). Our results suggest that targeting of MexB with siRNA appears to be a novel strategy for treating P. aeruginosa infections.

Inhibition of Cervical Cancer Cell Growth by Gene Silencing of HPV16 E6 Induced by Short-interfering RNA

  • Park, Sang-Muk;Lee, Sun-Kyung;Kim, Yoon-Sik
    • 대한임상검사과학회지
    • /
    • v.43 no.3
    • /
    • pp.89-97
    • /
    • 2011
  • The Human Papilloma Virus (HPV) infection has been strongly associated with pathogenesis of uterine cervix carcinoma. HPV type 16, a causative agent of uterine cervix carcinoma, encodes the E6 and E7 oncogenes, expression of which is pivotal for malignant transformation and maintenance of malignant phenotypes. To develop a gene therapy for HPV-related carcinoma, We investigated the effect of E6 short-interfering RNA (E6 siRNA) on the expression of this oncogene and on the growth of HPV 16-related uterine cervix carcinoma cells. SiHa cells, a uterine cervix carcinoma cell line, which contain a single copy of HPV 16 integrated in the chromosome and express the E6 and E7 oncogenes. Before 24 hr of transfection, cells were seeded and transfected with control plasmid or E6 siRNA-expressing plasmid. The mRNA was analysed by reverse transcriptase polymerase chain reaction (RT-PCR). The cell growth rate was investigated by MTT method. The E6 mRNA level in SiHa cells was decreased in HPV 16 E6 siRNA-expression vector transfected cells and a decrease in the growth of these cells was also observed. From these results. it is evident that E6 siRNA played a role in suppression of growth of SiHa cells and has a fair chance as a candidate for gene specific therapy for HPV related uterine cervix carcinoma.

  • PDF

Inhibition of Hepatitis B Virus Replication by in vitro Synthesized RNA

  • Yang, Yeon-Ju;Heo, Young-Shin;Kim, Jeong-Ki;Kim, Sang-Yong;Ahn, Jeong-Keun
    • Bulletin of the Korean Chemical Society
    • /
    • v.26 no.9
    • /
    • pp.1385-1389
    • /
    • 2005
  • Human hepatitis B virus (HBV) is a pathogen related to the development of liver diseases including chronic hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). However, the efficient methods to suppress HBV replication have not been developed yet. Therefore, we have used RNA interference (RNAi) as a potential tool for the suppression of HBV replication. Here, we designed a 21 nt small intefering dsRNA (siRNA) against hepatitis B virus X (HBx) RNA with 3' overhanging ends derived from T7 promoter. It has been reported that HBV X protein plays an important role in HBV gene expression and viral replication. The suppression of HBx gene expression by the 21 nt siRNA was investigated by Northern blot analysis and chloramphenicol acetyl transferase (CAT) assay. The level of HBx mRNA was decreased by siRNA in a dose-dependent manner. We also found that the 21 nt siRNA inhibited the HBV replication in hepatocellular carcinoma cell.

siRNA-mediated Silencing of Survivin Inhibits Proliferation and Enhances Etoposide Chemosensitivity in Acute Myeloid Leukemia Cells

  • Karami, Hadi;Baradaran, Behzad;Esfahani, Ali;Estiar, Mehrdad Asghari;Naghavi-Behzad, Mohammad;Sakhinia, Masoud;Sakhinia, Ebrahim
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.12
    • /
    • pp.7719-7724
    • /
    • 2013
  • Background: Overexpression of survivin, a known inhibitor of apoptosis, is associated with tumor progression and drug resistance in numerous malignancies, including leukemias. The aim of this study was to investigate the effect of a specific survivin small interference RNA (siRNA) on proliferation and the sensitivity of HL-60 acute myeloid leukemia (AML) cells to the chemotherapeutic drug etoposide. Materials and Methods: The cells were transfected with siRNAs using Lipofectamine $^{TM}2000$ transfection reagent. Relative survivin mRNA and protein levels were measured by quantitative real-time PCR and Western blotting, respectively. Trypan blue exclusion assays were performed to monitor tumor cell proliferation after siRNA transfection. The cytotoxic effects of etoposide and survivin siRNA, alone and in combination, on leukemic cells were determined using MTT assay. Apoptosis was assessed by ELISA cell death assay. Results: Survivin siRNA markedly reduced both mRNA and protein expression levels in a time-dependent manner, leading to distinct inhibition of cell proliferation and increased spontaneous apoptosis. Surprisingly, survivin siRNA synergistically increased the cell toxic effects of etoposide. Moreover, survivin down-regulation significantly enhanced its induction of apoptosis. Conclusions: Our study suggests that down-regulation of survivin by siRNA can trigger apoptosis and overcome drug resistance of leukemia cells. Therefore, survivin siRNA may be an effective adjuvant in AML chemotherapy.

Down-Regulation of Mcl-1 by Small Interference RNA Induces Apoptosis and Sensitizes HL-60 Leukemia Cells to Etoposide

  • Karami, Hadi;Baradaran, Behzad;Esfehani, Ali;Sakhinia, Masoud;Sakhinia, Ebrahim
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.2
    • /
    • pp.629-635
    • /
    • 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.

VEGF siRNA Delivery by a Cancer-Specific Cell-Penetrating Peptide

  • Lee, Young Woong;Hwang, Young Eun;Lee, Ju Young;Sohn, Jung-Hoon;Sung, Bong Hyun;Kim, Sun Chang
    • Journal of Microbiology and Biotechnology
    • /
    • v.28 no.3
    • /
    • pp.367-374
    • /
    • 2018
  • RNA interference provides an effective tool for developing antitumor therapies. Cell-penetrating peptides (CPPs) are delivery vectors widely used to efficiently transport small-interfering RNA (siRNA) to intracellular targets. In this study, we investigated the efficacy of the cancer-specific CPP carrier BR2 to specifically transport siRNA to cancer-target cells. Our results showed that BR2 formed a complex with anti-vascular endothelial growth factor siRNA (siVEGF) that exhibited the appropriate size and surface charge for in vivo treatment. Additionally, the BR2-VEGF siRNA complex exhibited significant serum stability and high levels of gene-silencing effects in vitro. Moreover, the transfection efficiency of the complex into a cancer cell line was higher than that observed in non-cancer cell lines, resulting in downregulated intracellular VEGF levels in HeLa cells and comprehensively improved antitumor efficacy in the absence of significant toxicity. These results indicated that BR2 has significant potential for the safe, efficient, and specific delivery of siRNA for diverse applications.

HDAC6 siRNA Inhibits Proliferation and Induces Apoptosis of HeLa Cells and its Related Molecular Mechanism

  • Qin, Hai-Xia;Cui, Hong-Kai;Pan, Ying;Yang, Jun;Ren, Yan-Fang;Hua, Cai-Hong;Hua, Fang-Fang;Qiao, Yu-Huan
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.13 no.7
    • /
    • pp.3367-3371
    • /
    • 2012
  • Objective: To investigate the effects of histone deacetylase 6 (HDAC6) siRNA on cell proliferation and cell apoptosis of the HeLa cervical carcinoma cell line and the molecular mechanisms involved. Methods: Division was into three groups: A, the untreated group; B, the control siRNA group; and C, the HDAC6 siRNA group. Lipofectamine 2000 was used for siRNA transfection, and Western blot analysis was used to determine the protein levels. Cell proliferation and apoptosis were characterized using a CCK-8 assay and flow cytometry, respectively. Results: HDAC6 protein expression in the HDAC6 siRNA-transfection group was significantly lower (P < 0.05) than in the untreated and control siRNA groups. The CCK-8 kit results demonstrated that the proliferation of HeLa cells was clearly inhibited in the HDAC6 siRNA transfection group (P < 0.05). In addition, flow cytometry revealed that the early apoptotic rate ($26.0%{\pm}0.87%$) was significantly elevated (P < 0.05) as compared with the untreated group ($10.6%{\pm}1.19%$) and control siRNA group ($8.61%{\pm}0.98%$). Furthermore, Western blot analysis indicated that bcl-2 protein expression in the HDAC6 siRNA-transfection group was down-regulated, whereas the expression of p21 and bax was up-regulated. Conclusion: HDAC6 plays an essential role in the occurrence and development of cervical carcinoma, and the down-regulation of HDAC6 expression may be useful molecular therapeutic method.

Interference of EGFP RNA in Human NT-2/D1 Cell Lines Using Human U6 Promoter-based siRNA PCR Products

  • Kwak, Young-Don;Sugaya, Kiminobu
    • Biotechnology and Bioprocess Engineering:BBE
    • /
    • v.11 no.3
    • /
    • pp.273-276
    • /
    • 2006
  • RNA interference (RNAi), a process of sequence-specific gene suppression, has been known as a natural gene regulatory mechanism in a wide range of lower organisms. Recently, we have reported that a transfection of human U6 promoter (hU6) driven hairpin small-interference RNA (siRNA) plasmid specifically knocks down the target gene by post-transcriptional gene silencing in mammalian cells. Here we report that transfection of polymerase chain reaction (PCR) products, containing human U6 promoter with hairpin siRNA, knocks down the target gene expression in human teratocarcinoma NT-2/D1 cells. Moreover, we showed 3' end termination sequence, 5 Ts, is not critical elements for knocking down in PCR-based siRNA system. Therefore, the PCR-based siRNA system is a promising tool not only for the screening but also to temporally regulate gene expression in the human progenitor cells.

Recyclable single-stranded DNA template for synthesis of siRNAs

  • Ali, Mussa M.;Obregon, Demian;Agrawal, Krishna C.;Mansour, Mahmoud;Abdel-Mageed, Asim B.
    • BMB Reports
    • /
    • v.43 no.11
    • /
    • pp.732-737
    • /
    • 2010
  • RNA interference is a post-transcriptional silencing mechanism triggered by the bioavailability and/or exogenous introduction of double-stranded RNA (dsRNA) into cells. Here we describe a novel method for the synthesis of siRNA in a single vessel. The method employs in vitro transcription and a single-stranded DNA (ssDNA) template and design, which incorporates upon self-annealing, two promoters, two templates, and three loop regions. Using this method of synthesis we generated efficacious siRNAs designed to silence both exogenous and endogenous genes in mammalian cells. Due to its unique design the single-stranded template is easily amenable to adaptation for attachment to surface platforms for synthesis of siRNAs. A siRNA synthesis platform was generated using a 3' end-biotinylated ssDNA template tethered to a streptavidin coated surface that generates stable siRNAs under multiple cycles of production. Together these data demonstrate a unique and robust method for scalable siRNA synthesis with potential application in RNAi-based array systems.