• Asian Pacific Journal of Cancer Prevention
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• 제14권12호
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• pp.7719-7724
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• 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.

• Asian Pacific Journal of Cancer Prevention
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• 제13권8호
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• pp.4007-4011
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• 2012

Purpose: Retinoblastoma-interacting zinc finger gene (RIZ1) is a tumor suppressor gene which is highly inactivated by promoter hypermethylation in patients with liver fluke-related cholangiocarcinoma (CCA). Epigenetic aberration of this gene might withdraw the ability to restrain tumor cell proliferation and migration. We aimed to define the role of RIZ1 on cell proliferation and migration in CCA cell line. Materials and methods: Small interference RNA (siRNA) was used to knock down the expression of RIZ1 in a CCA-derived cell line in which cell proliferation and cell migration were performed. Results: A predominant nuclear localization of RIZ1 was observed. Reduction of RIZ1 by siRNA augmented cell proliferation and migration. Conclusion: The result suggested that RIZ1 might play a role in regulating cell proliferation and migration in CCA. Reduction of RIZ1 expression may aggravate the progression of CCA.

• BMB Reports
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• 제45권1호
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• pp.20-25
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• 2012

The present study aimed to investigate the function of translationally controlled tumor protein (TCTP) in the regulation of Oct4 in mouse embryonic carcinoma P19 cells and mouse J1 embryonic stem (ES) cells. The mRNA level of endogenous TCTP in somatic cells was 2-4 folds higher than that in pluripotent P19 and J1 ES cells. Overexpression of TCTP in mouse pluripotent cells not only reduced the level of Oct4 transcription, but also decreased the pluripotency of stem cells. The N-terminal end of TCTP (amino acids 1-60) played an important role in suppressing the Oct4 promoter. Moreover, overexpression of TCTP in P19 cells suppressed the Oct4 promoter activity in a dose- and a time-dependent manner. In addition, knockdown of TCTP by small interfering RNA increased the expression of Oct4. Our study indicates that TCTP downregulates the Oct4 expression by binding the Sf1 site of Oct4 promoter in mouse pluripotent cells.

• Asian Pacific Journal of Cancer Prevention
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• 제16권9호
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• pp.4065-4069
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• 2015

Background: Epidermal growth factor-like domain multiple 7 (EGFL7), a secreted protein specifically expressed by endothelial cells during embryogenesis, recently was identified as a critical gene in tumor metastasis. Epithelial-mesenchymal transition (EMT) was found to be closely related with tumor progression. Accordingly, it is important to investigate the migration and EMT change after knock-down of EGFL7 gene expression in human pancreatic cancer cells. Materials and Methods: EGFL7 expression was firstly testified in 4 pancreatic cancer cell lines by real-time polymerase chain reaction (Real-time PCR) and western blot, and the highest expression of EGFL7 was found in PANC-1 cell line. Then, PANC-1 cells transfected with small interference RNA (siRNA) of EGFL7 using plasmid vector were named si-PANC-1, while transfected with negative control plasmid vector were called NC-PANC-1. Transwell assay was used to analyze the migration of PANC-1 cells. Real-time PCR and western blotting were used to detect the expression change of EGFL7 gene, EMT markers like E-Cadherin, N-Cadherin, Vimentin, Fibronectin and transcription factors like snail, slug in PANC-1, NCPANC-1, and si-PANC-1 cells, respectively. Results: After successful plasmid transfection, EGFL7 gene were dramatically knock-down by RNA interference in si-PANC-1 group. Meanwhile, migration ability decreased significantly, compared with PANC-1 and NC-PANC-1 group. Meanwhile, the expression of epithelial phenotype marker E-Cadherin increased and that of mesenchymal phenotype markers N-Cadherin, Vimentin, Fibronectin dramatically decreased in si-PANC-1 group, indicating a reversion of EMT. Also, transcription factors snail and slug decreased significantly after RNA interference. Conclusions: Current study suggested that highly-expressed EGFL7 promotes migration of PANC-1 cells and acts through transcription factors snail and slug to induce EMT, and further study is needed to confirm this issue.

• Asian Pacific Journal of Cancer Prevention
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• 제14권11호
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• pp.6305-6309
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• 2013

Background: TIAM2, a Rac guanine nucleotide exchange factor, is closely associated with cell adherence and migration. Here, we aimed to investigate the role of TIAM2 in non-small cell lung cancer (NSCLC) cells. Materials and Methods: A small interference RNA (siRNA) was introduced to silence the expression of TIAM2. Invasion and motility assays were then performed to assess the invasion and motility potential of NSCLC cells. GST-pull down assays were used to detect activation of Rac1. Results: TIAM2 was highly expressed in NSCLC cells. Knockdown of TIAM2 inhibited the invasion and motility, and suppressed activation of Rac1. Further experiments demonstrated that knockdown of TIAM2 could up-regulate the expression of E-cadherin, and down-regulate the expression of MMP-3, Twist and Snail. Conclusions: Our data suggest that TIAM2 can promote invasion and motility of NSCLC cells. Activation of Rac1 and regulation of some EMT/invasion-related genes may be involved in the underlying processes.

• Asian Pacific Journal of Cancer Prevention
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• 제16권7호
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• pp.3061-3065
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• 2015

Background: Rac3, a member of the Rac family of small guanosine triphosphatases (GTPases), regulates a variety of cell functions, including the organization of the cytoskeleton, cell migration, and invasion. Overexpression of Rac3 has been reported in several human cancers. However, the role of Rac3 in lung cancer (LC) has not been determined in detail. The purpose of this study was to investigate the effect of silencing of Rac3 expression in human LC cells and the consequences for cell survival. Materials and Methods: Lentivirus small hairpin RNA (shRNA) interference techniques were utilized to knock down the Rac3 gene. Gene and protein expression was quantified by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting. LC cell apoptosis was examined by annexin V-APC /propidium iodide staining. Results: Efficient silencing of Rac3 strongly inhibited A549 cell proliferation and colony formation ability, and significantly decreased tumor growth. Moreover, flow cytometry analysis showed that knockdown of Rac3 led to G2/M phase cell cycle arrest as well as an excess accumulation of cells in the G1 and S phase. Conclusions: Thus, functional analysis using shRNAs revealed a critical role for Rac3 in the tumor growth of LC cells. shRNA silencing of Rac3 could provide an effective strategy to treat LC.

• Asian Pacific Journal of Cancer Prevention
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• 제14권2호
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• pp.685-689
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• 2013

Objective: To study the effects of down-regulation of HDAC6 expression on proliferation, cell cycling and migration of esophageal squamous cell carcinoma (ESCC) cells and related molecular mechanisms. Methods: ESCC cell line EC9706 cells were randomly divided into untreated (with no transfection), control siRNA (transfected with control siRNA) and HDAC6 siRNA (transfected with HDAC6 small interfering RNA) groups. Effects of HDAC6 siRNA interference on expression of HDAC6 mRNA and protein in EC9706 cells were investigated by semi-quantitative RT-PCR, Western blotting and immunocytochemistry methods. Effects of down-regulation of HDAC6 expression on cell proliferation, cell cycle, and cell migration were studied using a CCK-8 kit, flow cytometry and Boyden chambers, respectively. Changes of mRNA and protein expression levels of cell cycle related factor (p21) and cell migration related factor (E-cadherin) were investigated by semi-quantitative RT-PCR and Western blotting methods. Results: After transfection of HDAC6 siRNA, the expression of HDAC6 mRNA and protein in EC9706 cells was significantly downregulated. In the HDAC6 siRNA group, cell proliferation was markedly inhibited, the percentage of cells in G0/G1 phase evidently increased and the percentage of cells in S phase decreased, and the number of migrating cells significantly and obviously decreased. The mRNA and protein expression levels of p21 and E-cadherin in the HDAC6 siRNA group were significantly higher than those in the untreated group and the control siRNA group, respectively. Conclusions: HDAC6 siRNA can effectively downregulate the expression of HDAC6 mRNA and protein in EC9706 cells. Down-regulation of HDAC6 expression can obviously inhibit cell proliferation, arrest cell cycling in the G0/G1 phase and reduce cell migration. The latter two functions may be closely related with the elevation of mRNA and protein expression of p21 and E-cadherin.

• Asian Pacific Journal of Cancer Prevention
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• 제15권12호
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• pp.4773-4780
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• 2014

Background: To investigate the effects of small interference RNA (siRNA) targeting BCR/ABL mRNA on proliferation and apoptosis in the K562 human chronic myeloid leukemia (CML) cell line and to provide a theoretical rationale and experimental evidence for its potential clinical application for anti-CML treatment. Materials and Methods: The gene sequence for BCR/ABL mRNA was found from the GeneBank. The target gene site on the BCR/ABL mRNA were selected according to Max-Planck-Institute (MPI) and rational siRNA design rules, the secondary structure of the candidate targeted mRNA was predicted, the relevant thermodynamic parameters were analyzed, and the targeted gene sequences were compared with BLAST to eliminate any sequences with significant homology. Inhibition of proliferation was evaluated by MTT assay and colony-formation inhibiting test. Apoptosis was determined by flow cytometry (FCM) and the morphology of apoptotic cells was identified by Giemsa-Wright staining. Western blotting was used to analyze the expression of BCR/ABL fusion protein in K562 cells after siRNA treatment. Results: The mRNA local secondary structure calculated by RNA structure software, and the optimal design of specific siRNA were contributed by bioinformatics rules. Five sequences of BCR/ABL siRNAs were designed and synthesized in vitro. Three sequences, siRNA1384, siRNA1276 and siRNA1786, which showed the most effective inhibition of K562 cell growth, were identified among the five candidate siRNAs, with a cell proliferative inhibitory rate nearly 50% after exposure to 12.5nmol/L~50nmol/L siRNA1384 for 24,48 and 72 hours. The 50% inhibitory concentrations ($IC_{50}$) of siRNA1384, siRNA1276 and siRNA1786 for 24hours were 46.6 nmol/L, 59.3 nmol/L and 62.6 nmol/L, respectively, and 65.668 nmol/L, 76.6 nmol/L, 74.4 nmol/L for 72 hours. The colony-formation inhibiting test also indicated that, compared with control, cell growth of siRNA treated group was inhibited. FCM results showed that the rate of cell apoptosis increased 24 hours after transfecting siRNA. The results of annexinV/PI staining indicated that the rate of apoptosis imcreased (1.53%, 15.3%, 64.5%, 57.5% and 21.5%) following treamtne with siRNAs (siRNA34, siRNA372, siRNA1384, siRNA1276 and siRNA1786). Morphological analysis showed td typical morphologic changes of apoptosis such as shrunken, fragmentation nucleus as well as "apoptotic bodies" after K562 cell exposure to siRNA. Western blot analysis showed that BCR/ABL protein was reduced sharply after a single dose of 50nmol/L siRNA transfection. Conclusions: Proliferation of K562 cells was remarkbly inhibited by siRNAs (siRNA1384, siRNA1276 and siRNA1786) in a concentration-dependent manner in vitro, with effective induction of apoptosis at a concentration of 50 nmol/L. One anti-leukemia mechanism in K562 cells appeared that BCR/ABL targeted protein was highly down-regulated. The siRNAs (siRNA1384, siRNA1276 and siRNA1786) may prove valuable in the treatment of CML.

• Biomolecules & Therapeutics
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• 제28권5호
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• pp.405-413
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• 2020

Fibroblast-like synoviocytes (FLS) play a crucial role in initiating rheumatoid arthritis. B-cell activating factor (BAFF) plays a role in FLS survival as well as in B cell maturation and maintenance. Here, we investigated whether tumor necrosis factor (TNF)-α-induced BAFF expression controls FLS migration and whether BAFF expression in FLS could be regulated by KR33426 which is the inhibitor of BAFF binding to BAFF receptors (BAFF-R) by using MH7A synovial cells transfected with the SV40 T antigen. More TNF-α-treated cells migrated compared to the control. TNF-α increased BAFF expression in FLS, significantly. FLS migration was inhibited by the transfection with BAFF-siRNA. KR33426 also inhibited BAFF expression increased by TNF-α treatment in FLS as judged by western blotting, PCR, and transcriptional activity assay. Kinases including JNK, p38 and Erk were activated by TNF-α treatment. While JNK and p38 were inhibited by KR33426 treatment, no changes in Erk were observed. Transcription factors including p65, c-Fos, CREB and SP1 were enhanced by TNF-α treatment. Among them, c-Fos was inhibited by KR33426 treatment. Small interference(si)-RNA of c-fos decreased BAFF transcriptional activity. FLS migration induced by TNF-α was inhibited by the transfection with BAFF-siRNA. KR33426 increased Twist, Snail, Cadherin-11 and N-Cadherin. In contrast, KR33426 decreased E-cadherin and TNF-α-enhanced CCL2. Taken together, our results demonstrate that synovial cell migration via CCL2 expression could be regulated by BAFF expression which is decreased by KR33426 and c-Fos-siRNA. It suggests for the first time that the role of BAFF-siRNA on FLS migration might be matched in the effect of KR33426 on BAFF expression.

• Asian Pacific Journal of Cancer Prevention
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• 제16권9호
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• pp.4133-4136
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• 2015

Background: To analyze multi-source data including publications and patents, and try to draw the whole landscape of the research and development community in the field of gene therapy for breast cancer. Materials and Methods: Publications and patents were collected from the Web of science and databases of the five major patent offices of the world, respectively. Bibliometric methodologies and technology are used to investigate publications/patents, their contents and relationships. Results: A total of 2,043 items published and 947 patents from 1994 to 2013 including "gene therapy for breast cancer" were retrieved. The top five countries in global publication share were USA, China, Germany, Japan and England. On the other hand, USA, Australia, England, South Korea and Japan were the main producers of patents. The universities and enterprises of USA had the highest amount of publication and patents. Adenovirus- and retrovirus-based gene therapies and small interfering RNA (siRNA) interference therapies were the main topics both in publications and patents. Conclusions: The above results show that global research in the field of gene therapy for breast cancer is increasing and the main participants in this field are USA and Canada in North America, China, Japan and South Korea in Asia, and England, Germany, and Italy in Europe. Also, this article demonstrates the usefulness of bibliometrics to address key evaluation questions and define future areas of research.