| フルテキストURL | PlosOne_2016_e0162394.PDF |
|---|---|
| 著者 | Arai, Kazuya| Eguchi, Takanori| Rahman, M. Mamunur| Sakamoto, Ruriko| Masuda, Norio| Nakatsura, Tetsuya| Calderwood, Stuart K.| Kozaki, Ken-ichi| Itoh, Manabu| |
| 抄録 | Epithelial-mesenchymal transition (EMT) is a crucial pathological event in cancer, particularly in tumor cell budding and metastasis. Therefore, control of EMT can represent a novel therapeutic strategy in cancer. Here, we introduce an innovative three-dimensional (3D) high-throughput screening (HTS) system that leads to an identification of EMT inhibitors. For the establishment of the novel 3D-HTS system, we chose NanoCulture Plates (NCP) that provided a gel-free micro-patterned scaffold for cells and were independent of other spheroid formation systems using soft-agar. In the NCP-based 3D cell culture system, A549 lung cancer cells migrated, gathered, and then formed multiple spheroids within 7 days. Live cell imaging experiments showed that an established EMT-inducer TGF-β promoted peripheral cells around the core of spheroids to acquire mesenchymal spindle shapes, loss of intercellular adhesion, and migration from the spheroids. Along with such morphological change, EMT-related gene expression signatures were altered, particularly alteration of mRNA levels of ECAD/CDH1, NCAD/CDH2, VIM and ZEB1/TCF8. These EMT-related phenotypic changes were blocked by SB431542, a TGF-βreceptor I (TGFβR1) inhibitor. Inside of the spheroids were highly hypoxic; in contrast, spheroid-derived peripheral migrating cells were normoxic, revealed by visualization and quantification using Hypoxia Probe. Thus, TGF-β-triggered EMT caused spheroid hypoplasia and loss of hypoxia. Spheroid EMT inhibitory (SEMTIN) activity of SB431542 was calculated from fluorescence intensities of the Hypoxia Probe, and then was utilized in a drug screening of EMT-inhibitory small molecule compounds. In a pilot screening, 9 of 1,330 compounds were above the thresholds of the SEMTIN activity and cell viability. Finally, two compounds SB-525334 and SU9516 showed SEMTIN activities in a dose dependent manner. SB-525334 was a known TGFβR1 inhibitor. SU9516 was a cyclin-dependent kinase 2 (CDK2) inhibitor, which we showed also had an EMT-inhibitory activity. The half maximal inhibitory concentration (IC50) of SB-525334 and SU9516 were 0.31 μM and 1.21 μM, respectively, while IC50 of SB431542 was 2.38 μM. Taken together, it was shown that this 3D NCP-based HTS system was useful for screening of EMT-regulatory drugs. |
| 発行日 | 2016-09-13 |
| 出版物タイトル | PLoS One |
| 巻 | 11巻 |
| 号 | 9号 |
| 出版者 | Public Library of Science |
| 開始ページ | e0162394 |
| ISSN | 1932-6203 |
| 資料タイプ | 学術雑誌論文 |
| 言語 | English |
| OAI-PMH Set | 岡山大学 |
| 著作権者 | https://creativecommons.org/licenses/by-nc-nd/4.0/deed.ja |
| 論文のバージョン | publisher |
| PubMed ID | 27622654 |
| DOI | 10.1371/journal.pone.0162394 |
| Web of Sience KeyUT | 000383681000029 |
| 関連URL | isVersionOf https://doi.org/10.1371/journal.pone.0162394 |
| フルテキストURL | K0005600_other1.pdf |
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| 著者 | Takeda, Tatsuaki| Yamamoto, Hiromasa| Kanzaki, Hirotaka| Suzawa, Ken| Yoshioka, Takahiro| Tomida, Shuta| Cui, Xiaojiang| Murali, Ramachandran| Namba, Kei| Sato, Hiroki| Torigoe, Hidejiro| Watanabe, Mototsugu| Shien, Kazuhiko| Soh, Junichi| Asano, Hiroaki| Tsukuda, Kazunori| Kitamura, Yoshihisa| Miyoshi, Shinichiro| Sendo, Toshiaki| Toyooka, Shinichi| |
| 抄録 | BACKGROUND: Overexpression of human epidermal growth factor receptor 2 (HER2) is observed in approximately 15-23% of breast cancers and these cancers are classified as HER2-positive breast cancer. Trastuzumab is the first-line targeted therapeutic drug for HER2-positive breast cancer and has improved patient overall survival. However, acquired resistance to trastuzumab is still a critical issue in breast cancer treatment. We previously established a trastuzumab-resistant breast cancer cell line (named as BT-474-R) from a trastuzumab-sensitive HER2-amplified cell line BT-474. Lapatinib is also a molecular-targeted drug for HER2-positive breast cancer, which acquired the resistance to trastuzumab. Acquired resistance to lapatinib is also an issue to be conquered. METHODS: We established trastuzumab/lapatinib-dual resistant cell line (named as BT-474-RL2) by additionally treating BT-474-R with lapatinib. We analyzed the mechanisms of resistance to trastuzumab and lapatinib. Besides, we analyzed the effect of the detected resistance mechanism in HER2-positive breast cancer patients. RESULTS: Proto-oncogene tyrosine-protein kinase Yes1, which is one of the Src family members, was amplified, overexpressed and activated in BT-474-R and BT-474-RL2. Silencing of Yes1 by siRNA induced both BT-474-R and BT-474-RL2 to restore the sensitivity to trastuzumab and lapatinib. Pharmaceutical inhibition of Yes1 by the Src inhibitor dasatinib was also effective to restore the sensitivity to trastuzumab and lapatinib in the two resistant cell lines. Combination treatment with dasatinib and trastuzumab induced down-regulation of signaling molecules such as HER2 and Akt. Moreover, the combination treatments induced G1-phase cell-cycle arrest and apoptosis. Consistent with cell line data, high expression of Yes1 mRNA was correlated with worse prognosis in patients with HER2-positive breast cancer. CONCLUSION: Yes1 plays an important role in acquired resistance to trastuzumab and lapatinib in HER2-positive breast cancer. Our data suggest that pharmacological inhibition of Yes1 may be an effective strategy to overcome resistance to trastuzumab and lapatinib. |
| 備考 | 学位審査副論文 |
| 発行日 | 2017-02-03 |
| 出版物タイトル | PLoS One |
| 巻 | 12巻 |
| 号 | 2号 |
| 出版者 | Public Library of Science |
| 開始ページ | e0171356 |
| ISSN | 1932-6203 |
| 資料タイプ | 学術雑誌論文 |
| 言語 | English |
| OAI-PMH Set | 岡山大学 |
| 著作権者 | https://creativecommons.org/licenses/by-nc-nd/4.0/deed.ja |
| 論文のバージョン | publisher |
| PubMed ID | 28158234 |
| DOI | 10.1371/journal.pone.0171356 |
| Web of Sience KeyUT | 000396161700064 |
| 関連URL | isVersionOf https://doi.org/10.1371/journal.pone.0171356 isPartOf http://ousar.lib.okayama-u.ac.jp/55525 |
| フルテキストURL | K0005592_other1.pdf |
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| 著者 | Hinamoto, Norikazu| Maeshima, Yohei| Yamasaki, Hiroko| Nasu, Tatsuyo| Saito, Daisuke| Watatani, Hiroyuki| Ujike, Haruyo| Tanabe, Katsuyuki| Masuda, Kana| Arata, Yuka| Sugiyama, Hitoshi| Sato, Yasufumi| Makino, Hirofumi| |
| 抄録 | Vasohibin-1 (VASH1) is a unique endogenous inhibitor of angiogenesis that is induced in endothelial cells by pro-angiogenic factors. We previously reported renoprotective effect of adenoviral delivery of VASH1 in diabetic nephropathy model, and herein investigated the potential protective role of endogenous VASH1 by using VASH1-deficient mice. Streptozotocin-induced type 1 diabetic VASH1 heterozygous knockout mice (VASH1(+/-)) or wild-type diabetic mice were sacrificed 16 weeks after inducing diabetes. In the diabetic VASH1(+/-) mice, albuminuria were significantly exacerbated compared with the diabetic wild-type littermates, in association with the dysregulated distribution of glomerular slit diaphragm related proteins, nephrin and ZO-1, glomerular basement membrane thickening and reduction of slit diaphragm density. Glomerular monocyte/macrophage infiltration and glomerular nuclear translocation of phosphorylated NF-κB p65 were significantly exacerbated in the diabetic VASH1(+/-) mice compared with the diabetic wild-type littermates, accompanied by the augmentation of VEGF-A, M1 macrophage-derived MCP-1 and phosphorylation of IκBα, and the decrease of angiopoietin-1/2 ratio and M2 macrophage-derived Arginase-1. The glomerular CD31(+) endothelial area was also increased in the diabetic VASH1(+/-) mice compared with the diabetic-wild type littermates. Furthermore, the renal and glomerular hypertrophy, glomerular accumulation of mesangial matrix and type IV collagen and activation of renal TGF-β1/Smad3 signaling, a key mediator of renal fibrosis, were exacerbated in the diabetic VASH1(+/-) mice compared with the diabetic wild-type littermates. In conditionally immortalized mouse podocytes cultured under high glucose condition, transfection of VASH1 small interfering RNA (siRNA) resulted in the reduction of nephrin, angiopoietin-1 and ZO-1, and the augmentation of VEGF-A compared with control siRNA. These results suggest that endogenous VASH1 may regulate the development of diabetic renal alterations, partly via direct effects on podocytes, and thus, a strategy to recover VASH1 might potentially lead to the development of a novel therapeutic approach for diabetic nephropathy. |
| 備考 | 学位審査副論文 |
| 発行日 | 2014-09-25 |
| 出版物タイトル | Plos One |
| 巻 | 9巻 |
| 号 | 9号 |
| 出版者 | Public Library of Science |
| 開始ページ | e107934 |
| ISSN | 1932-6203 |
| 資料タイプ | 学術雑誌論文 |
| 言語 | English |
| OAI-PMH Set | 岡山大学 |
| 著作権者 | https://creativecommons.org/licenses/by-nc-nd/4.0/ |
| 論文のバージョン | publisher |
| PubMed ID | 25255225 |
| DOI | 10.1371/journal.pone.0107934 |
| Web of Sience KeyUT | 000344862300045 |
| 関連URL | isVersionOf https://doi.org/10.1371/journal.pone.0107934 isPartOf http://ousar.lib.okayama-u.ac.jp/55517 |
| フルテキストURL | plosone_7_11_e50082.PDF |
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| 著者 | Kobuchi, Hirotsugu| Moriya, Koko| Ogino, Tetsuya| Fujita, Hirofumi| Inoue, Keiji| Shuin, Taro| Yasuda, Tatsuji| Utsumi, Kozo| Utsumi, Toshihiko| |
| 抄録 | Accumulation of protoporphyrin IX (PpIX) in malignant cells is the basis of 5-aminolevulinic acid (ALA)-mediated photodynamic therapy. We studied the expression of proteins that possibly affect ALA-mediated PpIX accumulation, namely oligopeptide transporter-1 and -2, ferrochelatase and ATP-binding cassette transporter G2 (ABCG2), in several tumor cell lines. Among these proteins, only ABCG2 correlated negatively with ALA-mediated PpIX accumulation. Both a subcellular fractionation study and confocal laser microscopic analysis revealed that ABCG2 was distributed not only in the plasma membrane but also intracellular organelles, including mitochondria. In addition, mitochondrial ABCG2 regulated the content of ALA-mediated PpIX in mitochondria, and Ko143, a specific inhibitor of ABCG2, enhanced mitochondrial PpIX accumulation. To clarify the possible roles of mitochondrial ABCG2, we characterized stably transfected-HEK (ST-HEK) cells overexpressing ABCG2. In these ST-HEK cells, functionally active ABCG2 was detected in mitochondria, and treatment with Ko143 increased ALA-mediated mitochondrial PpIX accumulation. Moreover, the mitochondria isolated from ST-HEK cells exported doxorubicin probably through ABCG2, because the export of doxorubicin was inhibited by Ko143. The susceptibility of ABCG2 distributed in mitochondria to proteinase K, endoglycosidase H and peptide-N-glycosidase F suggested that ABCG2 in mitochondrial fraction is modified by N-glycans and trafficked through the endoplasmic reticulum and Golgi apparatus and finally localizes within the mitochondria. Thus, it was found that ABCG2 distributed in mitochondria is a functional transporter and that the mitochondrial ABCG2 regulates ALA-mediated PpIX level through PpIX export from mitochondria to the cytosol. |
| 発行日 | 2012-11-26 |
| 出版物タイトル | PLoS ONE |
| 巻 | 7巻 |
| 号 | 11号 |
| 出版者 | Public Library of Science |
| 開始ページ | e50082 |
| ISSN | 1932-6203 |
| 資料タイプ | 学術雑誌論文 |
| 言語 | English |
| OAI-PMH Set | 岡山大学 |
| 著作権者 | https://creativecommons.org/licenses/by-nc-nd/4.0/deed.ja |
| 論文のバージョン | publisher |
| PubMed ID | 23189181 |
| DOI | 10.1371/journal.pone.0050082 |
| Web of Sience KeyUT | 000311929800058 |
| 関連URL | https://doi.org/10.1371/journal.pone.0050082 |