193 results on '"Takayuki Hattori"'
Search Results
2. Endogenous Endophthalmitis successfully treated with Intravitreal Povidone-iodine injection: a case report
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Hiroki Tanaka, Hiroyuki Nakashizuka, Yoshinobu Mizuno, and Takayuki Hattori
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Endogenous endophthalmitis ,Intravitreal injection ,Povidone iodine ,Ophthalmology ,RE1-994 - Abstract
Abstract Background The usefulness of povidone-iodine as an alternative to antimicrobial agents, for endophthalmitis, has recently been documented. We report a case of endogenous endophthalmitis successfully treated with intravitreal injection of povidone-iodine. Case presentation An 88-year-old woman underwent small bowel bypass surgery for postoperative ileus following rectal cancer resection. She developed a fever during total parenteral nutrition and was diagnosed with gram-positive cocci bacteremia of central venous catheter origin. The patient was referred to our department with chief complaints of ocular pain, hyperemia and decreased vision in the right eye, which had manifested during the febrile period. The initial examination revealed the visual acuity in her right eye to be finger counting and that in her left eye 0.2. The right eye showed a severe inflammatory reaction in the anterior chamber, fibrin deposition, and hypopyon. The fundus was difficult to visualize. Endogenous endophthalmitis due to bacteria was diagnosed. Surgical treatment was judged to be difficult based on the patient’s poor general condition and mental status, and intravitreal injection of 0.1 ml of 1.25% povidone-iodine was performed on the same day. The inflammation rapidly diminished, and the hypopyon had disappeared 4 days after treatment. The fundus became visible 7 days after treatment and there was no recurrence of endophthalmitis findings. The visual acuity in her right eye recovered to that in the left eye (0.2). Conclusion Intravitreal injection of povidone-iodine is potentially useful and effective as an alternative treatment of antibiotics for endogenous endophthalmitis patients, especially in whom surgical therapy is difficult.
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- 2020
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3. Prospective study of vitrectomy for epiretinal membranes in patients with good best-corrected visual acuity
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Hiroyuki Nakashizuka, Yorihisa Kitagawa, Yu Wakatsuki, Koji Tanaka, Koichi Furuya, Takayuki Hattori, Ryusaburo Mori, and Hiroyuki Shimada
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Epiretinal membrane ,Good visual acuity ,Metamorphopsia ,Aniseikonia ,Vitrectomy ,Ophthalmology ,RE1-994 - Abstract
Abstract Background To evaluate the efficacy of epiretinal membrane removal in patients with good best-corrected visual acuity (BCVA) for improving visual function and quality of life (QOL). Methods This prospective case study compared 37 subjects with preoperative BCVA ≦ 0.046 logMAR (Good group) to 35 patients with 0.10–0.52 logMAR (Moderate group) at 3 and 6 months. Linear mixed-effect models were used for statistical analysis. The primary outcome was the horizontal metamorphopsia score (MH) at 6 months postoperatively (post-6 M), while secondary outcomes were postoperative BCVA, vertical metamorphopsia score (MV), aniseikonia, stereopsis and central foveal thickness. In the Good group, QOL was assessed using the National Eye Institute Visual Functioning Questionnaire-25 (NEI VFQ-25) at 6 and 12 months. Results MH was significantly improved at post-3 M and post-6 M in the both groups but there were no significant differences between the two groups. MV showed no improvement at the final observation in either group. LogMAR BCVA was significantly improved at post-6 M in the Good group, which had significantly better vision than the Moderate group. Preoperative vertical and horizontal aniseikonia scores remained unchanged in the Good group at post-6 M but worsened in the Moderate group. The NEI VFQ-25 score improved in the Good group, reflecting improved general health, general vision, and mental health. Conclusions Early epiretinal surgery for patients with BCVA ≦ 0.046 logMAR was effective for improvement of HM, BCVA, and QOL and prevented worsening of aniseikonia. Trial registration UMIN000021220. Registered 10 September 2015. UMIN Clinical Trials Registry.
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- 2019
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4. An Arabidopsis PTH2 Gene Is Responsible for Gravity Resistance Supporting Plant Growth under Different Gravity Conditions
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Takayuki Hattori, Kouichi Soga, Kazuyuki Wakabayashi, and Takayuki Hoson
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Arabidopsis (Arabidopsis thaliana) ,cell wall ,cortical microtubules ,elongation growth ,gravity resistance ,hypergravity ,Science - Abstract
Terrestrial plants respond to and resist gravitational force. The response is termed “gravity resistance”, and centrifugal hypergravity conditions are efficient for investigating its nature and mechanism. A functional screening of Arabidopsis T-DNA insertion lines for the suppression rate of elongation growth of hypocotyls under hypergravity conditions was performed in this study to identify the genes required for gravity resistance. As a result, we identified PEPTIDYL-tRNA HYDROLASE II (PTH2). In the wild type, elongation growth was suppressed by hypergravity, but this did not happen in the pth2 mutant. Lateral growth, dynamics of cortical microtubules, mechanical properties of cell walls, or cell wall thickness were also not affected by hypergravity in the pth2 mutant. In other words, the pth2 mutant did not show any significant hypergravity responses. However, the gravitropic curvature of hypocotyls of the pth2 mutant was almost equal to that of the wild type, indicating that the PTH2 gene is not required for gravitropism. It is suggested by these results that PTH2 is responsible for the critical processes of gravity resistance in Arabidopsis hypocotyls.
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- 2022
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5. MCA1 and MCA2 Are Involved in the Response to Hypergravity in Arabidopsis Hypocotyls
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Takayuki Hattori, Yasuhiro Otomi, Yohei Nakajima, Kouichi Soga, Kazuyuki Wakabayashi, Hidetoshi Iida, and Takayuki Hoson
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Arabidopsis ,gravity resistance ,hypergravity ,MCA1 ,MCA2 ,mechanosensitive channel ,Botany ,QK1-989 - Abstract
Plants respond to and resist gravitational acceleration, but the mechanism of signal perception in the response is unknown. We studied the role of MCA (mid1-complementing activity) proteins in gravity perception by analyzing the expression of the MCA1 and MCA2 genes, and the growth of hypocotyls of mca mutants, under hypergravity conditions in the dark. An MCA1 promoter::GUS fusion reporter gene construct (MCA1p::GUS) and MCA2p::GUS were expressed almost universally in etiolated seedlings. Under hypergravity conditions, the expression levels of both genes increased compared with that under the 1 g condition, and remained higher, especially in the basal supporting region. On the other hand, mca-null and MCA-overexpressing seedlings showed normal growth under the 1 g condition. Hypergravity suppressed elongation growth of hypocotyls, but this effect was reduced in hypocotyls of mca-null mutants compared with the wild type. In contrast, MCA-overexpressing seedlings were hypersensitive to increased gravity; suppression of elongation growth was detected at a lower gravity level than that in the wild type. These results suggest that MCAs are involved in the perception of gravity signals in plants, and may be responsible for resistance to hypergravity.
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- 2020
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6. Proteasome inhibitors prevent cell death and prolong survival of mice challenged by Shiga toxin
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Takayuki Hattori, Miho Watanabe-Takahashi, Nobumichi Ohoka, Takashi Hamabata, Koichi Furukawa, Kiyotaka Nishikawa, and Mikihiko Naito
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Shiga toxin ,Apoptosis ,Apoptosis inhibitory proteins ,Proteasome ,Proteasome inhibitor ,Biology (General) ,QH301-705.5 - Abstract
Shiga toxin (Stx) causes fatal systemic complications. Stx induces apoptosis, but the mechanism of which is unclear. We report that Stx induced rapid reduction of short‐lived anti‐apoptotic proteins followed by activation of caspase 9 and the progression of apoptosis. Proteasome inhibitors prevented the reduction of anti‐apoptotic proteins, and inhibited caspase activation and apoptosis, suggesting that the reduction of anti‐apoptotic proteins is a prerequisite for Stx‐induced apoptosis. A clinically approved proteasome inhibitor, bortezomib, prolonged the survival of mice challenged by Stx. These results imply that proteasome inhibition may be a novel approach to prevent the fatal effects of Stx.
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- 2015
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7. Influence of foveal glial tissue after macular hole surgery on outer retinal restoration and visual acuity
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Iwasaki, Masanori, Nakashizuka, Hiroyuki, Tanaka, Koji, Wakatsuki, Yu, Onoe, Hajime, Nakagawa, Naoya, Fujimiya, Taishi, Koutari, Sawako, Sakakibara, Takuya, Shoda, Chiho, Hanaguri, Junya, Yokota, Harumasa, Takayuki, Hattori, Mori, Ryusaburo, Shimada, Hiroyuki, Nagaoka, Taiji, and Yamagami, Satoru
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- 2024
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8. Distinct and site-specific phosphorylation of the retinoblastoma protein at serine 612 in differentiated cells.
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Takayuki Hattori, Chiharu Uchida, Hirotaka Takahashi, Naoki Yamamoto, Mikihiko Naito, and Yoichi Taya
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Medicine ,Science - Abstract
The retinoblastoma susceptibility protein (pRB) is a phosphoprotein that regulates cell cycle progression at the G1/S transition. In quiescent and early G1 cells, pRB predominantly exists in the active hypophosphorylated form. The cyclin/cyclin-dependent protein kinase complexes phosphorylate pRB at the late G1 phase to inactivate pRB. This event leads to the dissociation and activation of E2F family transcriptional factors. At least 12 serine/threonine residues in pRB are phosphorylated in vivo. Although there have been many reports describing bulk phosphorylation of pRB, detail research describing the function of each phosphorylation site remains unknown. Besides its G1/S inhibitory function, pRB is involved in differentiation, prevention of cell death and control of tissue fate. To uncover the function of phosphorylation of pRB in various cellular conditions, we have been investigating phosphorylation of each serine/threonine residue in pRB with site-specific phospho-serine/threonine antibodies. Here we demonstrate that pRB is specifically phosphorylated at Ser612 in differentiated cells in a known kinase-independent manner. We also found that pRB phosphorylated at Ser612 still associates with E2F-1 and tightly binds to nuclear structures including chromatin. Moreover, expression of the Ser612Ala mutant pRB failed to induce differentiation. The findings suggest that phosphorylation of Ser612 provides a distinct function that differs from the function of phosphorylation of other serine/threonine residues in pRB.
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- 2014
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9. A COMPARATIVE STUDY OF MEDIUM-SIZED MACULAR HOLE SURGERY WITH INVERTED INTERNAL LIMITING MEMBRANE FLAP TECHNIQUE VERSUS CONVENTIONAL PEELING
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Iwasaki, Masanori, Nakashizuka, Hiroyuki, Tanaka, Koji, Wakatsuki, Yu, Onoe, Hajime, Sakakibara, Takuya, Nakagawa, Naoya, Fujimiya, Taishi, Koutari, Sawako, Kitagawa, Yorihisa, Takayuki, Hattori, Mori, Ryusaburo, and Shimada, Hiroyuki
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- 2024
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10. Rolling Guidance Filter as a Clustering Algorithm.
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Takayuki Hattori, Kohei Inoue, and Kenji Hara
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- 2021
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11. Generation of swirl flow by needle vibration for micro manipulation.
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Takayuki Hattori, Kazuto Kamiyama, Masaru Kojima, Mitsuhiro Horade, Yasushi Mae, and Tatsuo Arai
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- 2015
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12. Supplementary Figure 1 from Degradation of Tob1 Mediated by SCFSkp2-Dependent Ubiquitination
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Masatoshi Kitagawa, Hiroyuki Konno, Tadashi Yamamoto, Keiichi I. Nakayama, Shigetsugu Hatakeyama, Toshiaki Oda, Hirotoshi Kikuchi, Takayuki Hattori, Chiharu Uchida, Toru Suzuki, Kyoko Kitagawa, and Yoshihiro Hiramatsu
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Supplementary Figure 1 from Degradation of Tob1 Mediated by SCFSkp2-Dependent Ubiquitination
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- 2023
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13. Data from Pirh2 Promotes Ubiquitin-Dependent Degradation of the Cyclin-Dependent Kinase Inhibitor p27Kip1
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Masatoshi Kitagawa, Chiharu Uchida, Toshiaki Oda, Kyoko Kitagawa, Hirotoshi Kikuchi, Kenji Abe, Tomoyasu Isobe, and Takayuki Hattori
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The cyclin-dependent kinase inhibitor p27Kip1 is degraded in late G1 phase by the ubiquitin-proteasome pathway, allowing cells to enter S phase. Due to accelerated degradation of p27Kip1, various human cancers express low levels of p27Kip1 associated with poor prognosis. S-phase kinase–associated protein 2, the F-box protein component of an SCF ubiquitin ligase complex, is implicated in degradation of p27Kip1 during S-G2 phases. Recently, Kip1 ubiquitination–promoting complex has been reported as another ubiquitin ligase that targets cytoplasmic p27Kip1 exported from the nucleus in G0-G1 phases. Here, we identified a RING-H2–type ubiquitin ligase, Pirh2, as a p27Kip1-interacting protein. Endogenous Pirh2 physically interacted with endogenous p27Kip1 in mammalian cells. Pirh2 directly ubiquitinated p27Kip1 in an intact RING finger domain-dependent manner in vivo, as well as in vitro. Ablation of endogenous Pirh2 by small interfering RNA increased the steady-state level of p27Kip1 and decelerated p27Kip1 turnover. Depletion of Pirh2 induced accumulation of p27Kip1 in both the nucleus and cytoplasm. Pirh2 expression was induced from late G1-S phase, whereas p27Kip1 was decreased in synchronization with accumulation of Pirh2. Furthermore, reduction of Pirh2 resulted in an impairment of p27Kip1 degradation and an inhibition of cell cycle progression at G1-S transition in a p53-independent manner. Overall, the results indicate that Pirh2 acts as a negative regulator of p27Kip1 function by promoting ubiquitin-dependent proteasomal degradation. [Cancer Res 2007;67(22):10789–95]
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- 2023
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14. Supplementary Figures 1-6 from Up-regulation of GPR48 Induced by Down-regulation of p27Kip1 Enhances Carcinoma Cell Invasiveness and Metastasis
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Masatoshi Kitagawa, Hiroyuki Konno, Tatsuo Tanaka, Keiichi I. Nakayama, Keiko Nakayama, Toshiaki Oda, Takayuki Hattori, Chiharu Uchida, Mai Shimada, Tomoyasu Isobe, Hirotoshi Kikuchi, Yoshihiro Hiramatsu, Kyoko Kitagawa, and Yun Gao
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Supplementary Figures 1-6 from Up-regulation of GPR48 Induced by Down-regulation of p27Kip1 Enhances Carcinoma Cell Invasiveness and Metastasis
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- 2023
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15. Supplementary Figure 1 from Pirh2 Promotes Ubiquitin-Dependent Degradation of the Cyclin-Dependent Kinase Inhibitor p27Kip1
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Masatoshi Kitagawa, Chiharu Uchida, Toshiaki Oda, Kyoko Kitagawa, Hirotoshi Kikuchi, Kenji Abe, Tomoyasu Isobe, and Takayuki Hattori
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Supplementary Figure 1 from Pirh2 Promotes Ubiquitin-Dependent Degradation of the Cyclin-Dependent Kinase Inhibitor p27Kip1
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- 2023
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16. Data from Degradation of Tob1 Mediated by SCFSkp2-Dependent Ubiquitination
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Masatoshi Kitagawa, Hiroyuki Konno, Tadashi Yamamoto, Keiichi I. Nakayama, Shigetsugu Hatakeyama, Toshiaki Oda, Hirotoshi Kikuchi, Takayuki Hattori, Chiharu Uchida, Toru Suzuki, Kyoko Kitagawa, and Yoshihiro Hiramatsu
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Tob1, a member of the Tob/BTG family, is involved in the control of G1-S progression by suppressing cyclin D1 expression and acts as a tumor suppressor gene. Tob1 was reported to have a quick turnover through the ubiquitin-proteasome pathway, but proteins involved in this process are still unknown. We showed that Skp2, a substrate-targeting subunit of the SCF (Skp1/Cul1/F-box protein) ubiquitin ligase complex, was involved in ubiquitin-dependent degradation of Tob1. Skp2 interacted with Tob1 and facilitated ubiquitination of Tob1 in intact cells as well as in vitro. Skp2 mutants without the F-box or leucine rich repeat were not able to bind to Tob1 and did not enhance ubiquitination of Tob1. Tob1 was stabilized in both Skp2−/− mouse fibroblasts and Skp2 knockdown HeLa cells. Moreover, cyclin D1 expression was suppressed in Skp2 knockdown HeLa cells. These data suggest that Tob1 is a novel target for degradation by the SCF-Skp2 ubiquitin ligase. (Cancer Res 2006; 66(17): 8477-83)
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- 2023
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17. Data from Up-regulation of GPR48 Induced by Down-regulation of p27Kip1 Enhances Carcinoma Cell Invasiveness and Metastasis
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Masatoshi Kitagawa, Hiroyuki Konno, Tatsuo Tanaka, Keiichi I. Nakayama, Keiko Nakayama, Toshiaki Oda, Takayuki Hattori, Chiharu Uchida, Mai Shimada, Tomoyasu Isobe, Hirotoshi Kikuchi, Yoshihiro Hiramatsu, Kyoko Kitagawa, and Yun Gao
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A reduced expression level of the cyclin-dependent kinase inhibitor p27Kip1 is associated with increased tumor malignancy and poor prognosis in individuals with various types of cancer. To investigate the basis for this relation, we applied microarray analysis to screen for genes differentially expressed between p27+/− and parental (p27+/+) HCT116 human colon carcinoma cells. Expression of the gene for G protein–coupled receptor 48 (GPR48) was increased in the p27+/− cells. Forced expression of GPR48 increased both in vitro invasive activity and lung metastasis potency of HCT116 cells. In contrast, depletion of endogenous GPR48 by RNA interference reduced the invasive potential of HeLa and Lewis lung carcinoma cells not only in vitro but also in vivo. Moreover, GPR48 expression was significantly associated with lymph node metastasis and inversely correlated with p27 expression in human colon carcinomas. GPR48 may thus play an important role in invasiveness and metastasis of carcinoma and might therefore represent a potential prognostic marker or therapeutic target. (Cancer Res 2006; 66(24): 11623-31)
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- 2023
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18. Supplementary Figure 2 from Degradation of Tob1 Mediated by SCFSkp2-Dependent Ubiquitination
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Masatoshi Kitagawa, Hiroyuki Konno, Tadashi Yamamoto, Keiichi I. Nakayama, Shigetsugu Hatakeyama, Toshiaki Oda, Hirotoshi Kikuchi, Takayuki Hattori, Chiharu Uchida, Toru Suzuki, Kyoko Kitagawa, and Yoshihiro Hiramatsu
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Supplementary Figure 2 from Degradation of Tob1 Mediated by SCFSkp2-Dependent Ubiquitination
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- 2023
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19. Dynamic releasing of biological cells at high speed using parallel mechanism to control adhesion forces.
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Ebubekir Avci, Hiroyuki Yabugaki, Takayuki Hattori, Kazuto Kamiyama, Masaru Kojima, Yasushi Mae, and Tatsuo Arai
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- 2014
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20. Rolling Guidance Filter as a Clustering Algorithm
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Kohei Inoue, Takayuki Hattori, and Kenji Hara
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Artificial Intelligence ,Hardware and Architecture ,Filter (video) ,Computer science ,Computer Vision and Pattern Recognition ,Astrophysics::Cosmology and Extragalactic Astrophysics ,edge preserving smoothing ,rolling guidance filter ,Electrical and Electronic Engineering ,Cluster analysis ,Algorithm ,Software ,clustering - Abstract
We propose a generalization of the rolling guidance filter (RGF) to a similarity-based clustering (SBC) algorithm which can handle general vector data. The proposed RGF-based SBC algorithm makes the similarities between data clearer than the original similarity values computed from the original data. On the basis of the similarity values, we assign cluster labels to data by an SBC algorithm. Experimental results show that the proposed algorithm achieves better clustering result than the result by the naive application of the SBC algorithm to the original similarity values. Additionally, we study the convergence of a unimodal vector dataset to its mean vector.
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- 2021
21. Control of Navigable Panoramic Imagery with Information Furniture: Chair-Driven 2.5 with Automatic Window Dilation.
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Michael Cohen 0002, Kunihiro Doi, Takayuki Hattori, and Yorinobu Mine
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- 2007
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22. An Arabidopsis
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Takayuki, Hattori, Kouichi, Soga, Kazuyuki, Wakabayashi, and Takayuki, Hoson
- Abstract
Terrestrial plants respond to and resist gravitational force. The response is termed "gravity resistance", and centrifugal hypergravity conditions are efficient for investigating its nature and mechanism. A functional screening of Arabidopsis T-DNA insertion lines for the suppression rate of elongation growth of hypocotyls under hypergravity conditions was performed in this study to identify the genes required for gravity resistance. As a result, we identified
- Published
- 2022
23. Intraocular lens implantation and vitrectomy using 0.025% povidone-iodine in irrigation solution for bleb-related endophthalmitis
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Hiroyuki Nakashizuka, Yorihisa Kitagawa, Hiroyuki Shimada, Takayuki Hattori, and Yoshio Yamazaki
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medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,chemistry.chemical_element ,Vitrectomy ,Intraocular lens ,Iodine ,Letter To The Editor ,Ophthalmology ,chemistry ,lcsh:Ophthalmology ,lcsh:RE1-994 ,Medicine ,business ,Bleb related endophthalmitis - Published
- 2020
24. Difficulty in distinguishing radiation-induced prostate sarcoma from radiation mucositis in a patient with persistent urinary retention and hematuria after prostate cancer radiotherapy
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T. Imagumbai, Daisuke Yamashita, Yasuhiro Kosaka, Masaki Kokubo, Mutsushi Kawakita, Kengo Ogura, Takashi Ogata, Takayuki Hattori, and Shinya Hiraoka
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medicine.medical_specialty ,Prostate biopsy ,medicine.diagnostic_test ,Urinary retention ,business.industry ,medicine.medical_treatment ,Case Report ,Cystoscopy ,medicine.disease ,Radiation therapy ,Prostate Sarcoma ,Prostate cancer ,medicine ,Mucositis ,Radiology ,medicine.symptom ,business ,Transurethral resection of the prostate - Abstract
Urinary retention and hematuria owing to radiation-induced mucositis are occasional late adverse events in patients with prostate cancer. Moreover, radiation-induced secondary malignancies are late adverse events, although they are extremely rare. Herein, we describe a case of radiation-induced secondary malignancy of the prostate that was initially difficult to distinguish from radiation mucositis. A 74-year-old man with prostate cancer underwent brachytherapy and external beam radiotherapy 9 years ago. Twenty-eight months after irradiation, he presented with urinary retention and hematuria owing to radiation mucositis and underwent transurethral resection of the prostate. At 89 months after irradiation, the patient again showed urinary retention and hematuria. The cause of urinary retention and hematuria could not be identified on cystoscopy. Despite receiving medications, the patient’s symptoms did not improve. Therefore, transurethral fulguration was performed, and prostate biopsy revealed spindle cell sarcoma. A diagnosis of radiation-induced undifferentiated pleomorphic/spindle cell sarcoma was made, and the patient underwent total cystectomy and construction of the ileal conduit. Two weeks after the surgery, computed tomography revealed peritoneal dissemination. The patient died 5 weeks after the surgery. The case findings indicate that clinicians should consider the possibility of radiation-induced secondary malignancy; moreover, thorough pathological examination of the prostate with CT and MRI is important to distinguish RISM from radiation mucositis even if no tumors are found on cystoscopy.
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- 2020
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25. Kynurenine plays an immunosuppressive role in 2,4,6-trinitrobenzene sulfate-induced colitis in mice
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Kentaro Nakamoto, Yasuko Yamamoto, Hiroyuki Tomita, Masato Hoshi, Tatsuya Ando, Hiroyuki Tezuka, Kuniaki Saito, Akira Hara, Chieko Tashita, Takayuki Hattori, and Akihiro Hirata
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CD4-Positive T-Lymphocytes ,Male ,Colon ,Regulatory T cell ,T cell ,Inflammatory bowel disease ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,Kynurenine 3-monooxygenase ,0302 clinical medicine ,Immune system ,Inflammatory bowie diseases ,medicine ,Animals ,Homeostasis ,Colitis ,Kynurenine ,Sulfates ,Chemistry ,Tryptophan ,Gastroenterology ,FOXP3 ,General Medicine ,Basic Study ,medicine.disease ,Ulcerative colitis ,digestive system diseases ,Mice, Inbred C57BL ,Disease Models, Animal ,medicine.anatomical_structure ,Trinitrobenzenes ,030220 oncology & carcinogenesis ,Immunology ,030211 gastroenterology & hepatology ,Immunosuppressive Agents - Abstract
Background Inflammatory bowel disease, such as Crohn's disease and ulcerative colitis, is characterized by chronic intestinal inflammation leading to intestinal mucosal damage. Inflammatory bowel disease causes dysregulation of mucosal T cell responses, especially the responses of CD4+ T cells. Previously, we demonstrated that indoleamine-2,3-dioxygenase plays an immunosuppressive role in 2,4,6-trinitrobenzene sulfate (TNBS)-induced colitis. Although indoleamine-2,3-dioxygenase exerts immunosuppressive effects by altering the local concentration of tryptophan (Trp) and immunomodulatory Trp metabolites, the specific changes in immune regulation during colitis caused by Trp metabolites and its related enzymes remain unclear. Aim To investigate role of kynurenine 3-monooxygenase (KMO) in TNBS-induced colitis and involvement of Trp metabolites in maintenance of intestinal homeostasis. Methods Colitis was induced in eight-week-old male KMO+/+ or KMO-/- mice of C57BL/6N background using TNBS. Three days later, the colon was used for hematoxylin-eosin staining for histological grading, immunohistochemical or immunofluorescence staining for KMO, cytokines, and immune cells. Inflammatory and anti-inflammatory cytokines were measured using quantitative RT-PCR, and kynurenine (Kyn) pathway metabolites were measured by high-performance liquid chromatography. The cell proportions of colonic lamina propria and mesenteric lymph nodes were analyzed by flow cytometry. Results KMO expression levels in the colonic mononuclear phagocytes, including dendritic cells and macrophages increased upon TNBS induction. Notably, KMO deficiency reduced TNBS-induced colitis, resulting in an increased frequency of Foxp3+ regulatory T cells and increased mRNA and protein levels of anti-inflammatory cytokines, including transforming growth factor-β and interleukin-10. Conclusion Absence of KMO reduced TNBS-induced colitis via generation of Foxp3+ regulatory T cells by producing Kyn. Thus, Kyn may play a therapeutic role in colon protection during colitis.
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- 2020
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26. No increase in incidence of post-intravitreal injection endophthalmitis without topical antibiotics: a prospective study
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Koji Tanaka, Yuko Okubo, Hiroyuki Nakashizuka, Hiroyuki Shimada, Ryusaburo Mori, and Takayuki Hattori
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Vascular Endothelial Growth Factor A ,medicine.medical_specialty ,Administration, Topical ,Topical antibiotics ,Infectious endophthalmitis ,Angiogenesis Inhibitors ,Eye Infections, Bacterial ,03 medical and health sciences ,0302 clinical medicine ,Endophthalmitis ,Japan ,Retinal Diseases ,medicine ,Humans ,Prospective Studies ,Stage (cooking) ,Prospective cohort study ,business.industry ,Incidence ,Incidence (epidemiology) ,General Medicine ,University hospital ,medicine.disease ,Anti-Bacterial Agents ,Surgery ,Ophthalmology ,Intravitreal Injections ,030221 ophthalmology & optometry ,Conjunctival sac ,business ,030217 neurology & neurosurgery ,Follow-Up Studies - Abstract
In our previous report, intravitreal injection using 0.25% povidone-iodine to irrigate the conjunctival sac together with pre- and post-injection topical antibiotics achieved an incidence of post-injection endophthalmitis significantly lower than other reports. In this study, we examined whether similarly low incidence is achieved without using any topical antibiotics. Prospective cohort study. We evaluated intravitreal injections of anti-vascular endothelial growth factor agents conducted by vitreoretinal specialists at the outpatient injection room of a single university hospital. This study had two protocols. First stage: We performed more than 3000 injections with pre-injection but without post-injection topical antibiotics. Final stage: After confirming no case of endophthalmitis in the first stage, we performed more than 12,500 injections without either pre- or post-injection topical antibiotics. In both protocols, we used 0.25% povidone-iodine to sterilize the conjunctival sac both before and after injection. First stage was performed between April 2015 and January 2016. No case of suspected or proven infectious endophthalmitis occurred in 6039 injections [95% confidence interval (CI) 0–0.000497%]. Final stage was performed between February 2016 and November 2017. No case of suspected or proven infectious endophthalmitis occurred in 12,523 injections (95% CI 0–0.00024%). This result was comparable to our previous study using both pre- and post-injection topical antibiotics (0/15,144 injections, 95% CI 0–0.000198%). Using conjunctival sac irrigation with 0.25% povidone-iodine before and after intravitreal injection, the incidence of endophthalmitis remains low even when the use of pre- or post-injection topical antibiotics is discontinued.
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- 2019
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27. Long-Term Outcomes of Endovascular Stenting for Blunt Renal Artery Injuries with Stenosis: A Report of Five Consecutive Cases
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Yoshiaki Ichinose, Nobuaki Kiriu, Kohei Morimoto, Yuichi Koido, Takayuki Hattori, Junichi Inoue, Hiroshi Kato, Hiroyuki Yokota, and Ichiro Okada
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Adult ,Male ,medicine.medical_specialty ,Time Factors ,medicine.medical_treatment ,Renal function ,Renal Artery Obstruction ,Wounds, Nonpenetrating ,urologic and male genital diseases ,Renovascular hypertension ,Young Adult ,03 medical and health sciences ,Renal Artery ,0302 clinical medicine ,medicine.artery ,medicine ,Humans ,Renal artery ,Aged ,Retrospective Studies ,Arterial dissection ,business.industry ,Endovascular Procedures ,Accidents, Traffic ,General Medicine ,Middle Aged ,Revised Trauma Score ,medicine.disease ,Surgery ,Stenosis ,Hypertension, Renovascular ,Treatment Outcome ,030220 oncology & carcinogenesis ,Injury Severity Score ,Accidental Falls ,Female ,Stents ,030211 gastroenterology & hepatology ,Hemodialysis ,business - Abstract
Background Renal artery stenting is performed for renal artery injuries to preserve renal function and prevent renovascular hypertension. However, its indications are controversial and its long-term prognosis remains unknown. Here, we evaluate the characteristics and long-term outcomes of renal artery stenting for blunt renal artery injuries at our institution. Methods We retrospectively reviewed patients with blunt renal artery injuries who had been treated with stenting over a 12-year period at our institution. Five patients (three men and two women) were included. Results Trauma resulted from falls in three patients and motor vehicle accidents in two. All patients had experienced multiple injuries (median injury severity score, 24 [range, 16-48]; median revised trauma score, 5.9672 [4.0936-7.8408]; and median probability of survival, 0.689 [0.533-0.980]). All renal artery injuries involved stenosis because of traumatic arterial dissection or intimal tear; no cases of total occlusion were observed. No complications due to the intervention itself were observed. Although two patients developed reversible acute renal failure, none required long-term hemodialysis. One patient with renovascular hypertension was treated with antihypertensive agents for a month and subsequently became normotensive without further medication. All patients underwent postoperative computed tomography, which revealed no stent occlusion or renal atrophy. Renal scintigraphy for three patients demonstrated preserved differential renal function. All five patients survived. Conclusions Renal artery stenting for hemodynamically stable blunt renal artery injuries with stenosis is suggested to be safe and helps in avoiding long-term hemodialysis and renovascular hypertension.
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- 2019
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28. Plan comparison of prostate stereotactic radiotherapy in spacer implant patients
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Keiji Kitatani, Shuichirou Miyazaki, Hiroshi Mayahara, Kazufusa Mizonobe, Tomonori Yabuuchi, Yuichirou Shiota, Hiroaki Akasaka, Risako Sakamoto, Aya Harada, Yuya Oki, Takayuki Hattori, and Kazuyuki Uehara
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Male ,medicine.medical_treatment ,hydrogel spacer ,Radiosurgery ,plan comparison ,Tomotherapy ,Stereotactic radiotherapy ,Prostate cancer ,Cyberknife ,Prostate ,Medicine ,Dosimetry ,Humans ,Radiation Oncology Physics ,Radiology, Nuclear Medicine and imaging ,Instrumentation ,Retrospective Studies ,Radiation ,SBRT ,business.industry ,Radiotherapy Planning, Computer-Assisted ,Truebeam ,Radiotherapy Dosage ,medicine.disease ,prostate cancer ,medicine.anatomical_structure ,Implant ,Radiotherapy, Intensity-Modulated ,business ,Nuclear medicine - Abstract
In prostate stereotactic body radiation therapy (SBRT), hydrogel spacers are increasingly used. This study aimed to perform a dosimetry comparison of treatment plans using CyberKnife (CK), commonly used for prostate SBRT, Helical TomoTherapy (HT), and TrueBeam (TB) in patients with hydrogel spacer implantations. The data of 20 patients who received hydrogel spacer implantation for prostate SBRT were retrospectively analyzed. The prescription dose was 36.25 Gy in five fractions to 95% of the planning target volume (PTV; D95). The conformity index (CI), gradient index (GI), homogeneity index (HI), and dose‐volume histogram (DVH) were analyzed for the three modalities, using the same PTV margins. The monitor unit (MU) and the beam‐on‐time (BOT) values were subsequently compared. The CI of TB (0.93 ± 0.02) was significantly superior to those of CK (0.82 ± 0.03, p
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- 2021
29. Design and synthesis of cell-permeable fluorescent nitrilotriacetic acid derivatives
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Masaaki Kurihara, Hideshi Inoue, Mikihiko Naito, Genichiro Tsuji, Takayuki Hattori, Wataru Hakamata, Takuji Shoda, Yosuke Demizu, and Masashi Kato
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Boron Compounds ,Nitrilotriacetic Acid ,Cell Membrane Permeability ,Clinical Biochemistry ,Pharmaceutical Science ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Fluorescence ,Cell Line ,Green fluorescent protein ,Cell membrane ,chemistry.chemical_compound ,Drug Discovery ,Fluorescence microscope ,medicine ,Humans ,Molecular Biology ,Fluorescent Dyes ,010405 organic chemistry ,Chemistry ,Hydrolysis ,Organic Chemistry ,Nitrilotriacetic acid ,0104 chemical sciences ,medicine.anatomical_structure ,Membrane ,Microscopy, Fluorescence ,Biophysics ,Molecular Medicine ,Intracellular ,Conjugate - Abstract
Fluorescence labeling of the target molecules using a small molecule-based probe is superior than a method using genetically expressed green fluorescence protein (GFP) in terms of convenience in its preparation and functionalization. Fluorophore-nitrilotriacetic acid (NTA) conjugates with several ester protecting groups were synthesized and evaluated for their cell membrane permeability by fluorescence microscopy analysis. One of the derivatives, acetoxymethyl (AM)-protected NTA conjugate is hydrolyzed, resulting in intracellular accumulation, thus providing localized fluorescence intensity in cells. This modification is expected as an effective method for converting a non-cell membrane permeable NTA-BODIPY conjugates to a cell membrane permeable derivatives.
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- 2018
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30. Acquired Resistance to Shiga Toxin-Induced Apoptosis by Loss of CD77 Expression in Human Myelogenous Leukemia Cell Line, THP-1
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Takayuki Hattori, Miho Watanabe-Takahashi, Mikihiko Naito, and Kiyotaka Nishikawa
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0301 basic medicine ,THP-1 Cells ,Pharmaceutical Science ,Apoptosis ,Biology ,Shiga Toxin 1 ,Shiga Toxin 2 ,Virulence factor ,03 medical and health sciences ,Myelogenous ,Downregulation and upregulation ,hemic and lymphatic diseases ,medicine ,Humans ,THP1 cell line ,Etoposide ,Pharmacology ,Trihexosylceramides ,Shiga toxin ,General Medicine ,Galactosyltransferases ,medicine.disease ,Antineoplastic Agents, Phytogenic ,Leukemia ,030104 developmental biology ,Leukemia, Myeloid ,Toxicity ,Cancer research ,biology.protein - Abstract
Shiga toxin (Stx) is a main virulence factor of Enterohemorrhagic Escherichia coli (EHEC) that causes diarrhea and hemorrhagic colitis and occasionally fatal systemic complications. Stx induces rapid apoptotic cell death in some cells, such as human myelogenous leukemia THP-1 cells expressing CD77, a receptor for Stx internalization, and the induction of apoptotic cell death is thought to be crucial for the fatal systemic complications. Therefore, in order to suppress the fatal toxicity, it is important to understand the mechanism how cells can escape from apoptotic cell death in the presence of Stx. In this study, we isolated resistant clones to Stx-induced apoptosis from highly sensitive THP-1 cells by continuous exposure with lethal dose of Stx. All of the ten resistant clones lost the expression of CD77 as a consequence of the reduction in CD77 synthase mRNA expression. These results suggest that downregulation of CD77 or CD77 synthase expression could be a novel approach to suppress the fatal toxicity of Stx in EHEC infected patient.
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- 2018
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31. Pharmacological difference between degrader and inhibitor against oncogenic BCR-ABL kinase
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Osamu Ujikawa, Takayuki Hattori, Nobumichi Ohoka, Nobuo Cho, Naoki Miyamoto, Norihito Shibata, Hiroshi Nara, Kenichiro Shimokawa, Katsunori Nagai, Tomoya Sameshima, and Mikihiko Naito
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0301 basic medicine ,musculoskeletal diseases ,Ubiquitin-Protein Ligases ,Dasatinib ,Fusion Proteins, bcr-abl ,lcsh:Medicine ,Antineoplastic Agents ,Ligands ,Article ,03 medical and health sciences ,chemistry.chemical_compound ,Cell Line, Tumor ,Leukemia, Myelogenous, Chronic, BCR-ABL Positive ,hemic and lymphatic diseases ,medicine ,Humans ,Kinase activity ,Protein kinase A ,lcsh:Science ,Protein Kinase Inhibitors ,neoplasms ,Cell Proliferation ,Multidisciplinary ,ABL ,Kinase ,Cell growth ,lcsh:R ,medicine.disease ,body regions ,030104 developmental biology ,Cross-Linking Reagents ,chemistry ,Drug Design ,Proteolysis ,Cancer research ,lcsh:Q ,Growth inhibition ,Chronic myelogenous leukemia ,medicine.drug - Abstract
Chronic myelogenous leukemia (CML) is characterized by the oncogenic fusion protein, BCR-ABL protein kinase, against which clinically useful inhibitors have been developed. An alternative approach to treat CML is to degrade the BCR-ABL protein. Recently, potent degraders against BCR-ABL have been developed by conjugating dasatinib to ligands for E3 ubiquitin ligases. Since the degraders contain the dasatinib moiety, they also inhibit BCR-ABL kinase activity, which complicates our understanding of the impact of BCR-ABL degradation by degraders in CML growth inhibition. To address this issue, we chose DAS-IAP, as a potent BCR-ABL degrader, and developed a structurally related inactive degrader, DAS-meIAP, which inhibits kinase activity but does not degrade the BCR-ABL protein. DAS-IAP showed slightly weaker activity than DAS-meIAP in inhibiting cell growth when CML cells were treated for 48 h. However, DAS-IAP showed sustained growth inhibition even when the drug was removed after short-term treatment, whereas CML cell growth rapidly resumed following removal of DAS-meIAP and dasatinib. Consistently, suppression of BCR-ABL levels and downstream kinase signaling were maintained after DAS-IAP removal, whereas kinase signaling rapidly recovered following removal of DAS-meIAP and dasatinib. These results indicate that BCR-ABL degrader shows more sustained inhibition of CML cell growth than ABL kinase inhibitor.
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- 2018
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32. Derivatization of inhibitor of apoptosis protein (IAP) ligands yields improved inducers of estrogen receptor α degradation
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Osamu Ujikawa, Yoko Morita, Kenichiro Shimokawa, Takayuki Hattori, Masahiro Ito, Tomoya Sameshima, Keiichiro Okuhira, Katsunori Nagai, Ikuo Fujimori, Yasuhiro Imaeda, Hiroshi Nara, Ryokichi Koyama, Mikihiko Naito, Youji Hayase, Nobuo Cho, Nobumichi Ohoka, Norihito Shibata, and Osamu Sano
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0301 basic medicine ,Down-Regulation ,Estrogen receptor ,Antineoplastic Agents ,X-Linked Inhibitor of Apoptosis Protein ,Ligands ,Inhibitor of apoptosis ,Biochemistry ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Ubiquitin ,Animals ,Humans ,Molecular Biology ,biology ,Ligand ,Chemistry ,Estrogen Receptor alpha ,Ubiquitination ,Cell Biology ,Xenograft Model Antitumor Assays ,Cell biology ,XIAP ,Thiazoles ,030104 developmental biology ,Proteasome ,Protein Synthesis and Degradation ,Apoptosis ,030220 oncology & carcinogenesis ,Proteolysis ,Cancer cell ,MCF-7 Cells ,biology.protein ,Protein Binding - Abstract
Aberrant expression of proteins often underlies many diseases, including cancer. A recently developed approach in drug development is small molecule-mediated, selective degradation of dysregulated proteins. We have devised a protein-knockdown system that utilizes chimeric molecules termed specific and nongenetic IAP-dependent protein erasers (SNIPERs) to induce ubiquitylation and proteasomal degradation of various target proteins. SNIPER(ER)-87 consists of an inhibitor of apoptosis protein (IAP) ligand LCL161 derivative that is conjugated to the estrogen receptor α (ERα) ligand 4-hydroxytamoxifen by a PEG linker, and we have previously reported that this SNIPER efficiently degrades the ERα protein. Here, we report that derivatization of the IAP ligand module yields SNIPER(ER)s with superior protein-knockdown activity. These improved SNIPER(ER)s exhibited higher binding affinities to IAPs and induced more potent degradation of ERα than does SNIPER(ER)-87. Further, they induced simultaneous degradation of cellular inhibitor of apoptosis protein 1 (cIAP1) and delayed degradation of X-linked IAP (XIAP). Notably, these reengineered SNIPER(ER)s efficiently induced apoptosis in MCF-7 human breast cancer cells that require IAPs for continued cellular survival. We found that one of these molecules, SNIPER(ER)-110, inhibits the growth of MCF-7 tumor xenografts in mice more potently than the previously characterized SNIPER(ER)-87. Mechanistic analysis revealed that our novel SNIPER(ER)s preferentially recruit XIAP, rather than cIAP1, to degrade ERα. Our results suggest that derivatized IAP ligands could facilitate further development of SNIPERs with potent protein-knockdown and cytocidal activities against cancer cells requiring IAPs for survival.
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- 2018
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33. Wet laboratory training using porcine eyes with eyelids
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Hiroyuki Nakashizuka, Ari Shinojima, Yumiko Machida, Hiroyuki Shimada, Mitsuko Yuzawa, Takayuki Hattori, Yuko Okubo, and Yu Wakatsuki
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Male ,medicine.medical_specialty ,genetic structures ,Swine ,medicine.medical_treatment ,Cataract Extraction ,Vitreoretinal Surgery ,Eye Enucleation ,03 medical and health sciences ,0302 clinical medicine ,Ophthalmology ,medicine ,Animals ,Humans ,Aged ,business.industry ,Eyelids ,General Medicine ,Cataract surgery ,eye diseases ,medicine.anatomical_structure ,Education, Medical, Graduate ,030221 ophthalmology & optometry ,Female ,sense organs ,Eyelid ,business ,030217 neurology & neurosurgery - Abstract
Objective This study aimed to evaluate the usefulness of a new wet laboratory (wet lab) system using porcine eyes with eyelids. Design Teaching device trial. Participants Porcine eyes with orbital tissues and eyelids. Methods Twenty porcine eyes with orbital tissues and eyelids were enucleated from pigs butchered at age 6 months. These eyes were positioned in the eye sockets of a model head and stabilized with a pin. Eye draping, dressing with tape, and speculum placement were conducted. The vertical and horizontal widths of the palpebra under the speculum setting were compared with those of 55 patients who underwent cataract surgery. The rotation and torsion of the porcine eye in the new wet lab system were also compared with those of a conventional wet lab system. For comparison with actual cataract surgery, 5 ophthalmologists, including residents, were asked to respond to a questionnaire survey. Results The horizontal widths of the palpebra under the speculum setting were 27.5 ± 3.1 mm in porcine eyes and 28.6 ± 5.1 mm in human eyes, and the vertical widths were 16.9 ± 1.3 mm and 16.1 ± 1.5 mm (p = 0.53, 0.05). The amounts of rotation and torsion were significantly greater with the new wet lab system. Ophthalmologists evaluated the new wet lab system as being more realistic than the conventional system, in terms of both natural eye movement and restriction of the surgical field by the eyelid and the speculum. Conclusions Wet lab training using porcine eyes with eyelids is more practical than older systems as it reproduces an ocular surgical field very similar to that of humans.
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- 2017
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34. Development of a Small Hybrid Molecule That Mediates Degradation of His-Tag Fused Proteins
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Mikihiko Naito, Koyo Okitsu, Takashi Misawa, Takuji Shoda, Yosuke Demizu, Masaaki Kurihara, and Takayuki Hattori
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Nitrilotriacetic Acid ,0301 basic medicine ,Leupeptins ,Receptors, Retinoic Acid ,Recombinant Fusion Proteins ,Ubiquitin-Protein Ligases ,Biotin ,Smad2 Protein ,Computational biology ,Cell Line ,Maleimides ,03 medical and health sciences ,Drug Discovery ,Organometallic Compounds ,Humans ,Molecule ,Histidine ,Cysteine ,Chemistry ,Ligand ,A protein ,Small molecule ,Combinatorial chemistry ,030104 developmental biology ,Proteolysis ,Molecular Medicine ,Degradation (geology) ,Target protein ,Proteasome Inhibitors ,Function (biology) - Abstract
In recent years, the induction of target-protein degradation via the ubiquitin-proteasome system (UPS) mediated by small molecules has attracted attention, and this approach has applications in pharmaceutical development. However, this technique requires a ligand for the target protein that can be incorporated into tailor-made molecules, and there are many proteins for which such ligands have not been found. In this study, we developed a protein-knockdown method that recognizes a His-tag fused to a protein of interest. This strategy theoretically allows comprehensive targeting of proteins of interest by a particular molecule recognizing the tag. As expected, our hybrid molecule 10 [SNIPER(CH6)] efficiently degraded His-tagged CRABP-II and Smad2 in cells. This system provides an easy method to determine the susceptibility of proteins of interest to UPS-mediated degradation. Furthermore, we hope that this method will become an efficient tool to analyze the function of the UPS.
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- 2017
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35. SNIPER(TACC3) induces cytoplasmic vacuolization and sensitizes cancer cells to Bortezomib
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Nobumichi Ohoka, Mikihiko Naito, Nobuo Cho, Takayuki Hattori, Hiroshi Nara, Norihito Shibata, and Katsunori Nagai
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0301 basic medicine ,Cytoplasm ,Proteasome Endopeptidase Complex ,Cancer Research ,Programmed cell death ,SNIPER(TACC3) ,Apoptosis ,X-Linked Inhibitor of Apoptosis Protein ,Endoplasmic Reticulum ,Inhibitor of apoptosis ,Bortezomib ,Small Molecule Libraries ,03 medical and health sciences ,XIAP ,Cell Line, Tumor ,Antineoplastic Combined Chemotherapy Protocols ,medicine ,Humans ,cytoplasmic vacuolization ,Cell Death ,Chemistry ,Drug Synergism ,Original Articles ,General Medicine ,Endoplasmic Reticulum Stress ,Drug Discovery and Delivery ,030104 developmental biology ,Oncology ,Vacuolization ,Cancer cell ,MCF-7 Cells ,Unfolded protein response ,Cancer research ,paraptosis ,Original Article ,K562 Cells ,Microtubule-Associated Proteins ,medicine.drug - Abstract
We previously developed a hybrid small molecule SNIPER (Specific and Nongenetic IAP-dependent Protein ERaser) against transforming acidic coiled-coil-3 (TACC3), SNIPER(TACC3), that induces proteasomal degradation of TACC3 protein. In this study, we found that SNIPER(TACC3) induces cytoplasmic vacuolization derived from endoplasmic reticulum (ER) and paraptosis-like cell death selectively in cancer cells. Mechanistic analysis suggests that accumulation of ubiquitylated protein aggregates that requires X-linked inhibitor of apoptosis protein (XIAP) induces ER stress, which results in ER-stress responses involving X-box binding protein-1 (XBP-1) and ER-derived vacuolization in cancer cells. Importantly, inhibition of proteasome enhanced the SNIPER(TACC3)-induced vacuolization, and the combination treatment of SNIPER(TACC3) and bortezomib exhibited a synergistic anticancer activity in several cancer cell lines. The induction of paraptosis-like cell death in cancer cells by SNIPER(TACC3) could be applied to treat cancer cells resistant to undergo apoptosis by overexpression of XIAP.
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- 2017
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36. Reduced anterior chamber contamination by frequent surface irrigation with diluted iodine solutions during cataract surgery
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Mitsuko Yuzawa, Hiroyuki Shimada, Takayuki Hattori, Shinji Arai, and Hiroyuki Nakashizuka
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Male ,0301 basic medicine ,Staphylococcus aureus ,Corneal endothelium ,Visual acuity ,genetic structures ,Anterior Chamber ,medicine.medical_treatment ,chemistry.chemical_element ,Balanced salt solution ,Cataract Extraction ,Iodine ,Eye Infections, Bacterial ,Intraoperative Period ,03 medical and health sciences ,0302 clinical medicine ,Endophthalmitis ,medicine ,Humans ,Surgical Wound Infection ,Prospective Studies ,Therapeutic Irrigation ,Povidone-Iodine ,Surface irrigation ,Aged ,Aged, 80 and over ,business.industry ,General Medicine ,Middle Aged ,Staphylococcal Infections ,Cataract surgery ,Contamination ,medicine.disease ,eye diseases ,Ophthalmology ,Treatment Outcome ,030104 developmental biology ,chemistry ,Anesthesia ,Anti-Infective Agents, Local ,030221 ophthalmology & optometry ,Female ,sense organs ,Ophthalmic Solutions ,medicine.symptom ,business ,Follow-Up Studies - Abstract
Purpose To verify that ocular surface irrigation with 0.025% povidone-iodine (PI) or 0.0025% polyvinyl alcohol-iodine (PAI) during cataract surgery minimizes bacterial contamination of the anterior chamber. Methods The study was a prospective, interventional case series. First, the bactericidal effect of PI or PAI against Staphylococcus aureus was evaluated in vitro. Next, in 400 eyes undergoing cataract surgery, the ocular surface was irrigated every 20 seconds during surgery with balanced salt solution (BSS; 200 eyes) or BSS containing 0.025% PI (100 eyes) or 0.0025% PAI (100 eyes). At the completion of surgery, anterior chamber fluid was cultured bacteriologically. Visual acuity (VA) and corneal endothelial cell density were measured before and 7 days after surgery. Results A marked bactericidal effect was observed when S. aureus was directly exposed for 15 seconds to 0.01% PI or 0.001% PAI diluted in BSS. When the two solutions were stored at room temperature, bactericidal effect did not attenuate after 60 min. The bacterial detection rate at the completion of surgery was significantly reduced in 0.025% PI (0%, 0/100 eyes) or 0.0025% PAI group (0%, 0/100 eyes) compared to BSS group (5%, 10/200 eyes) (p = 0.0340). No differences in postoperative visual acuity and postoperative corneal endothelial cell density were observed between three groups. Conclusion In cataract surgery, irrigation every 20 seconds of the operative field with 0.025% PI or 0.0025% PAI, both of which contain 0.0025% available iodine concentration, achieved a very low bacterial contamination rate in the anterior chamber.
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- 2017
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37. In Vivo Knockdown of Pathogenic Proteins via Specific and Nongenetic Inhibitor of Apoptosis Protein (IAP)-dependent Protein Erasers (SNIPERs)
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Nobumichi Ohoka, Norihito Shibata, Mikihiko Naito, Kenichiro Shimokawa, Nobuo Cho, Hiroshi Nara, Hirokazu Matsumoto, Osamu Sano, Ryokichi Koyama, Hisashi Fujita, Masahiro Ito, Katsunori Nagai, Yasuhiro Imaeda, Takayuki Hattori, Keiichiro Okuhira, Osamu Ujikawa, and Mika Teratani
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0301 basic medicine ,BRD4 ,Gene knockdown ,Estrogen receptor ,Cell Biology ,Biology ,Inhibitor of apoptosis ,Biochemistry ,Cell biology ,XIAP ,Ubiquitin ligase ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Proteasome ,Ubiquitin ,Protein Synthesis and Degradation ,030220 oncology & carcinogenesis ,biology.protein ,Molecular Biology - Abstract
Many diseases, especially cancers, result from aberrant or overexpression of pathogenic proteins. Specific inhibitors against these proteins have shown remarkable therapeutic effects, but these are limited mainly to enzymes. An alternative approach that may have utility in drug development relies on selective degradation of pathogenic proteins via small chimeric molecules linking an E3 ubiquitin ligase to the targeted protein for proteasomal degradation. To this end, we recently developed a protein knockdown system based on hybrid small molecule SNIPERs (Specific and Nongenetic IAP-dependent Protein Erasers) that recruit inhibitor of the apoptosis protein (IAP) ubiquitin ligases to specifically degrade targeted proteins. Here, we extend our previous study to show a proof of concept of the SNIPER technology in vivo. By incorporating a high affinity IAP ligand, we developed a novel SNIPER against estrogen receptor α (ERα), SNIPER(ER)-87, that has a potent protein knockdown activity. The SNIPER(ER) reduced ERα levels in tumor xenografts and suppressed the growth of ERα-positive breast tumors in mice. Mechanistically, it preferentially recruits X-linked IAP (XIAP) rather than cellular IAP1, to degrade ERα via the ubiquitin-proteasome pathway. With this IAP ligand, potent SNIPERs against other pathogenic proteins, BCR-ABL, bromodomain-containing protein 4 (BRD4), and phosphodiesterase-4 (PDE4) could also be developed. These results indicate that forced ubiquitylation by SNIPERs is a useful method to achieve efficient protein knockdown with potential therapeutic activities and could also be applied to study the role of ubiquitylation in many cellular processes.
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- 2017
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38. Protein Degradation Inducers SNIPERs and Protacs against Oncogenic Proteins
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Norihito Shibata, Nobumichi Ohoka, Takayuki Hattori, and Mikihiko Naito
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Chemistry ,Inducer ,Protein degradation ,Cell biology - Published
- 2019
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39. Development of a Potent Protein Degrader against Oncogenic BCR-ABL Protein
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Nobumichi Ohoka, Mikihiko Naito, Norihito Shibata, and Takayuki Hattori
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Proteasome Endopeptidase Complex ,Fusion Proteins, bcr-abl ,Down-Regulation ,Antineoplastic Agents ,010402 general chemistry ,Inhibitor of apoptosis ,01 natural sciences ,Inhibitor of Apoptosis Proteins ,hemic and lymphatic diseases ,Leukemia, Myelogenous, Chronic, BCR-ABL Positive ,Drug Discovery ,medicine ,Humans ,neoplasms ,Gene knockdown ,biology ,010405 organic chemistry ,Chemistry ,Ubiquitination ,Imatinib ,General Chemistry ,General Medicine ,Oncogenes ,medicine.disease ,Fusion protein ,0104 chemical sciences ,Ubiquitin ligase ,Dasatinib ,Proteasome ,Drug Resistance, Neoplasm ,biology.protein ,Cancer research ,medicine.drug ,Chronic myelogenous leukemia - Abstract
Chromosomal translocation occurs in some cancer cells, resulting in the expression of aberrant oncogenic fusion proteins that include BCR-ABL in chronic myelogenous leukemia (CML). Inhibitors of ABL tyrosine kinase, such as imatinib and dasatinib, exhibit remarkable therapeutic effects, although emergence of drug resistance hampers the therapy during long-term treatment. An alternative approach to treat CML is to downregulate expression of the BCR-ABL protein. Recently, we have devised a protein knockdown system by hybrid molecules named Specific and Nongenetic inhibitor of apoptosis protein [IAP]-dependent Protein Erasers (SNIPER). This system is designed to induce IAP-mediated ubiquitylation and proteasomal degradation of target proteins. In this review, we describe the development of SNIPER against BCR-ABL, and discuss the features and prospect for treatment of CML.
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- 2019
40. Anterior Lens Capsule Transplantation for Acquired Optic Disc Pit Maculopathy
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Hiroyuki Nakashizuka, Takayuki Hattori, Koji Tanaka, Koichi Furuya, Yumiko Machida, Yu Wakatsuki, Hajime Onoe, Yorihisa Kitagawa, and Ryusaburo Mori
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medicine.medical_specialty ,genetic structures ,medicine.medical_treatment ,Optic Disk ,Lens Capsule, Crystalline ,Vitrectomy ,Posterior vitreous detachment ,03 medical and health sciences ,0302 clinical medicine ,Retinal Diseases ,Ophthalmology ,Optic pit ,Optic Nerve Diseases ,medicine ,Humans ,Aged ,Retrospective Studies ,Retina ,business.industry ,medicine.disease ,eye diseases ,Transplantation ,medicine.anatomical_structure ,030221 ophthalmology & optometry ,Maculopathy ,Female ,sense organs ,Tamponade ,business ,Optic disc - Abstract
A patient with acquired optic disc pit (ODP) maculopathy underwent vitrectomy with anterior capsule transplantation to the ODP and gas tamponade. Structural changes were evaluated by enhanced depth imaging optical coherence (OCT) tomography. During vitrectomy, the eye was confirmed to have preexisting posterior vitreous detachment. Postoperative OCT showed complete closure of the optic pit resulting in rapid absorption of subretinal fluid. The authors' observations suggest that the anterior capsule is a useful material for achieving optic pit closure. To the authors' knowledge, this is the first report describing application of the anterior capsule to the treatment of ODP maculopathy. [ Ophthalmic Surg Lasers Imaging Retina. 2019;50:649–652.]
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- 2018
41. Intravitreal Injection of 1.25% Povidone Iodine Followed by Vitrectomy Using 0.025% Povidone Iodine Irrigation for Treating Endophthalmitis
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Hiroyuki Shimada, Kei Shinoda, Takayuki Hattori, Hiroyuki Nakashizuka, Koji Tanaka, and Yorihisa Kitagawa
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medicine.medical_specialty ,genetic structures ,medicine.medical_treatment ,Biomedical Engineering ,vitrectomy ,electroretinogram ,chemistry.chemical_element ,Vitrectomy ,Iodine ,chemistry.chemical_compound ,Endophthalmitis ,Ophthalmology ,medicine ,medicine.diagnostic_test ,povidone iodine ,business.industry ,intravitreal injection ,Retinal ,Perioperative ,Articles ,Functional recovery ,University hospital ,medicine.disease ,eye diseases ,chemistry ,endophthalmitis ,sense organs ,business ,Electroretinography - Abstract
Purpose To investigate the safety and effectiveness of intravitreal injection (IVI) of 1.25% povidone iodine (PI) followed by vitrectomy using 0.025% PI irrigation for treating endophthalmitis. Methods Prospective case series study. Nine eyes of 8 patients with postoperative or endogenous endophthalmitis treated at the Nihon University Hospital between April 2015 and October 2017 were studied. First, IVI of 0.1 mL/1.25%PI was conducted, followed by anterior chamber irrigation and vitrectomy using 0.025%PI irrigation solution. Corneal epithelial damage, anterior chamber inflammation, and vitreous inflammation were assessed and fundus examinations were performed, using a slit-lamp microscope and indirect ophthalmoscopy. A specular microscope, Goldmann perimetry, and electroretinography (ERG) were also used. Results In all but case 7, endophthalmitis resolved rapidly and good visual acuity was maintained. No adverse events were noted. Furthermore, the perioperative ERG showed improvements in the oscillatory potentials amplitudes on ERG and flicker ERG, as well as in the implicit time of the a-wave, suggesting functional recovery in the retinal outer and inner layers after therapy. Conclusions IVI of PI followed by vitrectomy was thought to be a safe and effective treatment for endophthalmitis. Translational relevance We succeeded in proving the clinical safety of IVI of PI followed by vitrectomy with PI irrigation as well as previous experimental reports. PI is available in world widely, therefore this method will be optimal treatment for endophthalmitis.
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- 2018
42. Protein Knockdown Technology: Application of Ubiquitin Ligase to Cancer Therapy
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Nobumichi Ohoka, Mikihiko Naito, Norihito Shibata, and Takayuki Hattori
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0301 basic medicine ,Proteasome Endopeptidase Complex ,Cancer Research ,Receptors, Retinoic Acid ,Ubiquitin-Protein Ligases ,Down-Regulation ,Receptors, Cytoplasmic and Nuclear ,Antineoplastic Agents ,Cell Cycle Proteins ,Ligands ,Inhibitor of Apoptosis Proteins ,03 medical and health sciences ,Ubiquitin ,Downregulation and upregulation ,Leucine ,Neoplasms ,Drug Discovery ,Animals ,Humans ,Molecular Targeted Therapy ,Pharmacology ,Gene knockdown ,biology ,Protein Stability ,Ubiquitination ,Small molecule ,Neoplasm Proteins ,Ubiquitin ligase ,Cell biology ,Cytosol ,030104 developmental biology ,Oncology ,Biochemistry ,Drug Design ,Proteolysis ,Cancer cell ,biology.protein ,Target protein ,Oligopeptides ,Signal Transduction - Abstract
Selective degradation of pathogenic proteins by small molecules in cells is a novel approach for development of therapeutic agents against various diseases, including cancer. We and others have developed a protein knockdown technology with a series of hybrid small compounds, called SNIPERs (Specific and Nongenetic IAP-dependent Protein ERasers); and peptidic chimeric molecules, called PROTACs (proteolysis-targeting chimeric molecules), which induce selective degradation of target proteins via the ubiquitin-proteasome pathway. These compounds include two different ligands connected by a linker; one is a ligand for a ubiquitin ligase and the other is a ligand for the target protein, which are expected to crosslink these proteins in cells. Theoretically, any cytosolic protein can be targeted for degradation by this technology. To date, several SNIPERs and PROTACs against various oncogenic proteins have been developed, which specifically induce polyubiquitylation and proteasomal degradation of the oncogenic proteins, resulting in cell death, growth arrest, or impaired migration of cancer cells. Thus, this protein knockdown technology has a great potential for cancer therapy.
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- 2016
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43. RANDOMIZED CONTROLLED STUDY OF INTRAVITREAL BEVACIZUMAB 0.16 MG INJECTED ONE DAY BEFORE SURGERY FOR PROLIFERATIVE DIABETIC RETINOPATHY
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Mitsuko Yuzawa, Ayumu Manabe, Hiroyuki Nakashizuka, Hiroyuki Shimada, and Takayuki Hattori
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Adult ,Male ,Vascular Endothelial Growth Factor A ,medicine.medical_specialty ,genetic structures ,Bevacizumab ,Premedication ,medicine.medical_treatment ,Visual Acuity ,Angiogenesis Inhibitors ,Vitrectomy ,Retinal Neovascularization ,Young Adult ,chemistry.chemical_compound ,Double-Blind Method ,Electrocoagulation ,medicine ,Humans ,Prospective Studies ,Fluorescein Angiography ,Aged ,Aged, 80 and over ,Diabetic Retinopathy ,medicine.diagnostic_test ,business.industry ,General Medicine ,Diabetic retinopathy ,Middle Aged ,medicine.disease ,Fluorescein angiography ,eye diseases ,Surgery ,Vitreous Body ,Vascular endothelial growth factor ,Ophthalmology ,chemistry ,Intravitreal Injections ,Vitreous hemorrhage ,Female ,sense organs ,Vascular endothelial growth factor production ,business ,Tomography, Optical Coherence ,Follow-Up Studies ,medicine.drug - Abstract
Purpose: To investigate the usefulness of 0.16 mg/0.05 mL intravitreal bevacizumab (IVB) injection 1 day before vitrectomy for proliferative diabetic retinopathy. Methods: Sixty-two patients with proliferative diabetic retinopathy (66 eyes) with an indication for primary vitrectomy were randomized to IVB group (34 eyes) or sham control group (32 eyes). Intravitreal bevacizumab group received intravitreal injection of 0.16 mg/0.05 mL bevacizumab, and sham control group received sham injection 1 day before vitrectomy. Vitreous fluid was sampled before vitrectomy was started. Results: Frequency of reoperation due to recurrent vitreous hemorrhage within 4 weeks after surgery was significantly lower (P = 0.033) in IVB group (3.1%, 1/32) than in sham control group (20.6%, 7/34). The number of intraoperative endodiathermy spots (0.63 ± 1.0 vs. 1.3 ± 1.4, P = 0.025) and frequency of postoperative recurrent vitreous hemorrhage (3.1%, 1/32 vs. 23.5%, 8/34, P = 0.017) were significantly lower in IVB group than in sham control group. Vitreous vascular endothelial growth factor concentrations were 1315.3 ± 1153.4 pg/mL in sham control group and 25.0 ± 13.6 pg/mL in IVB group (P Conclusion: Intravitreal injection of 0.16 mg/0.05 mL bevacizumab 1 day before vitrectomy blocked vascular endothelial growth factor production in vitreous and significantly reduced the incidence of reoperation due to early postoperative recurrent vitreous hemorrhage.
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- 2015
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44. VITRECTOMY USING 0.025% POVIDONE–IODINE IN BALANCED SALT SOLUTION PLUS FOR THE TREATMENT OF POSTOPERATIVE ENDOPHTHALMITIS
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Hiroyuki Shimada, Takayuki Hattori, Naomi Kokubo, Hiroyuki Nakashizuka, Mitsuko Yuzawa, and Takayasu Noguchi
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Adult ,Male ,Staphylococcus aureus ,medicine.medical_specialty ,medicine.medical_treatment ,Colony Count, Microbial ,chemistry.chemical_element ,Balanced salt solution ,Vitrectomy ,Microbial Sensitivity Tests ,Experimental laboratory ,Iodine ,medicine.disease_cause ,Eye Infections, Bacterial ,Postoperative endophthalmitis ,Postoperative Complications ,medicine ,Humans ,Therapeutic Irrigation ,Povidone-Iodine ,Aged ,Aged, 80 and over ,Endophthalmitis ,business.industry ,General Medicine ,Middle Aged ,Staphylococcal Infections ,Bactericidal effect ,Combined Modality Therapy ,Glutathione ,Surgery ,Bicarbonates ,Drug Combinations ,Ophthalmology ,chemistry ,Anesthesia ,Anti-Infective Agents, Local ,Female ,business - Abstract
To investigate the bactericidal effect of 0.025% povidone-iodine in Balanced Salt Solution PLUS (0.025% PI-BSS PLUS) and its use in vitrectomy for postoperative endophthalmitis.First, an experimental laboratory model using Staphylococcus aureus was used to evaluate the bactericidal effect of PI-BSS PLUS. Next, in a case series of 4 eyes with postoperative endophthalmitis, vitrectomy using 0.025% PI-BSS PLUS as irrigation solution was conducted, followed by postoperative intravitreal and intravenous antibiotics.In in vitro study, PI at concentrations of 0.01% and above in BSS PLUS exhibited marked bactericidal effect after 15 seconds of exposure. Bactericidal effect of 0.025% PI-BSS PLUS was maintained at room temperature storage for 15 minutes but was attenuated after 30 minutes. Among 4 eyes that underwent vitrectomy using 0.025% PI-BSS PLUS, coagulase-negative Staphylococcus sp. was isolated in 1 eye at the beginning but not at completion of surgery. In all four eyes, endophthalmitis was resolved with no adverse events. Ocular toxicity was not observed.The 0.025% PI-BSS PLUS is bactericidal and nontoxic when used as irrigation solution in vitrectomy. In 4 cases of postoperative endophthalmitis, vitrectomy using 0.025% PI-BSS PLUS followed by postoperative antibiotics resolved endophthalmitis.
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- 2015
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45. Japanese guidelines for the management of acute pancreatitis: Japanese Guidelines 2015
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Takao Itoi, Toshifumi Gabata, Toshihiko Mayumi, Masamichi Yokoe, Shuji Isaji, Morihisa Hirota, Keita Wada, Tadahiro Takada, Masahiko Hirota, Yasutoshi Kimura, Seiki Kiriyama, Takayuki Hattori, Shinju Arata, Satoru Shikata, Masumi Kadoya, Hisato Igarashi, Koichi Hirata, Keisho Kataoka, Masahiro Yoshida, Miho Sekimoto, Naohiro Sata, Nobuya Kitamura, Yoshifumi Takeyama, Kunihiro Shirai, and Kazunori Takeda
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Diagnostic Imaging ,medicine.medical_specialty ,Hepatology ,Abdominal compartment syndrome ,Pancreatitis, Acute Necrotizing ,business.industry ,Disease Management ,Guideline ,medicine.disease ,law.invention ,Japan ,Randomized controlled trial ,law ,Intensive care ,Practice Guidelines as Topic ,Epidemiology ,medicine ,Etiology ,Humans ,Acute pancreatitis ,Pancreatitis ,Surgery ,Intensive care medicine ,business - Abstract
Background Japanese (JPN) guidelines for the management of acute pancreatitis were published in 2006. The severity assessment criteria for acute pancreatitis were later revised by the Japanese Ministry of Health, Labour and Welfare (MHLW) in 2008, leading to their publication as the JPN Guidelines 2010. Following the 2012 revision of the Atlanta Classifications of Acute Pancreatitis, in which the classifications of regional complications of pancreatitis were revised, the development of a minimally invasive method for local complications of pancreatitis spread, and emerging evidence was gathered and revised into the JPN Guidelines. Methods A comprehensive evaluation was carried out on the evidence for epidemiology, diagnosis, severity, treatment, post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis and clinical indicators, based on the concepts of the GRADE system (Grading of Recommendations Assessment, Development and Evaluation). With the graded recommendations, where the evidence was unclear, Meta-Analysis team for JPN Guidelines 2015 conducted an additional new meta-analysis, the results of which were included in the guidelines. Results Thirty-nine questions were prepared in 17 subject areas, for which 43 recommendations were made. The 17 subject areas were: Diagnosis, Diagnostic imaging, Etiology, Severity assessment, Transfer indication, Fluid therapy, Nasogastric tube, Pain control, Antibiotics prophylaxis, Protease inhibitor, Nutritional support, Intensive care, management of Biliary Pancreatitis, management of Abdominal Compartment Syndrome, Interventions for the local complications, Post-ERCP pancreatitis and Clinical Indicator (Pancreatitis Bundles 2015). Meta-analysis was conducted in the following four subject areas based on randomized controlled trials: (1) prophylactic antibiotics use; (2) prophylactic pancreatic stent placement for the prevention of post-ERCP pancreatitis; (3) prophylactic non-steroidal anti-inflammatory drugs (NSAIDs) for the prevention of post-ERCP pancreatitis; and (4) peritoneal lavage. Using the results of the meta-analysis, recommendations were graded to create useful information. In addition, a mobile application was developed, which made it possible to diagnose, assess severity and check pancreatitis bundles. Conclusions The JPN Guidelines 2015 were prepared using the most up-to-date methods, and including the latest recommended medical treatments, and we are confident that this will make them easy for many clinicians to use, and will provide a useful tool in the decision-making process for the treatment of patients, and optimal medical support. The free mobile application and calculator for the JPN Guidelines 2015 is available via http://www.jshbps.jp/en/guideline/jpn-guideline2015.html
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- 2015
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46. Proteasome inhibitors prevent cell death and prolong survival of mice challenged by Shiga toxin
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Kiyotaka Nishikawa, Takayuki Hattori, Nobumichi Ohoka, Mikihiko Naito, Takashi Hamabata, Miho Watanabe-Takahashi, and Koichi Furukawa
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Programmed cell death ,Mcl-1, myeloid cell leukemia 1 ,QH301-705.5 ,Poly ADP ribose polymerase ,Apoptosis inhibitory proteins ,Apoptosis ,Biology ,General Biochemistry, Genetics and Molecular Biology ,ER, endoplasmic reticulum ,PI, propidium iodide ,CHX, cycloheximide ,hemic and lymphatic diseases ,Research article ,medicine ,Proteasome inhibitor ,Biology (General) ,STEC, Shiga toxin-producing Escherichia coli ,c-IAP1, cellular inhibitor of apoptosis protein 1 ,FLIP, FLICE (FADD-like IL-1β-converting enzyme)-inhibitory protein ,Caspase-9 ,Proteasome ,Bortezomib ,Shiga toxin ,BRZ, bortezomib ,Immunology ,biology.protein ,Cancer research ,Stx, Shiga toxin ,PARP, Poly(ADP-ribose) polymerase ,medicine.drug - Abstract
Highlights • Shiga toxin (Stx) rapidly reduces the level of short-lived anti-apoptotic proteins. • Stx induces activation of caspase 9 and apoptosis. • Proteasome inhibitors prevent the reduction of anti-apoptotic proteins. • Proteasome inhibitors suppress Stx-induced apoptosis. • Bortezomib prolongs the survival of mice challenged with a lethal dose of Stx., Shiga toxin (Stx) causes fatal systemic complications. Stx induces apoptosis, but the mechanism of which is unclear. We report that Stx induced rapid reduction of short-lived anti-apoptotic proteins followed by activation of caspase 9 and the progression of apoptosis. Proteasome inhibitors prevented the reduction of anti-apoptotic proteins, and inhibited caspase activation and apoptosis, suggesting that the reduction of anti-apoptotic proteins is a prerequisite for Stx-induced apoptosis. A clinically approved proteasome inhibitor, bortezomib, prolonged the survival of mice challenged by Stx. These results imply that proteasome inhibition may be a novel approach to prevent the fatal effects of Stx.
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- 2015
47. Targeting the Allosteric Site of Oncoprotein BCR-ABL as an Alternative Strategy for Effective Target Protein Degradation
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Takayuki Hattori, Tomoya Sameshima, Nobuo Cho, Hiroshi Nara, Mikihiko Naito, Naoki Miyamoto, Osamu Ujikawa, Nobumichi Ohoka, Kenichiro Shimokawa, and Norihito Shibata
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0301 basic medicine ,Drug discovery ,Organic Chemistry ,Allosteric regulation ,Chemical biology ,Biology ,Protein degradation ,Biochemistry ,Small molecule ,XIAP ,Ubiquitin ligase ,03 medical and health sciences ,030104 developmental biology ,hemic and lymphatic diseases ,Drug Discovery ,biology.protein ,Target protein - Abstract
Protein degradation technology based on hybrid small molecules is an emerging drug modality that has significant potential in drug discovery and as a unique method of post-translational protein knockdown in the field of chemical biology. Here, we report the first example of a novel and potent protein degradation inducer that binds to an allosteric site of the oncogenic BCR-ABL protein. BCR-ABL allosteric ligands were incorporated into the SNIPER (Specific and Nongenetic inhibitor of apoptosis protein [IAP]-dependent Protein Erasers) platform, and a series of in vitro biological assays of binding affinity, target protein modulation, signal transduction, and growth inhibition were carried out. One of the designed compounds, 6 (SNIPER(ABL)-062), showed desirable binding affinities against ABL1, cIAP1/2, and XIAP and consequently caused potent BCR-ABL degradation.
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- 2017
48. Simple and efficient knockdown of His-tagged proteins by ternary molecules consisting of a His-tag ligand, a ubiquitin ligase ligand, and a cell-penetrating peptide
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Norikazu Yamazaki, Mikihiko Naito, Koyo Okitsu, Takayuki Hattori, Masaaki Kurihara, Yosuke Demizu, Nobumichi Ohoka, Takashi Misawa, and Norihito Shibata
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0301 basic medicine ,Nitrilotriacetic Acid ,Stereochemistry ,Receptors, Retinoic Acid ,Ubiquitin-Protein Ligases ,Clinical Biochemistry ,Pharmaceutical Science ,Peptide ,Cell-Penetrating Peptides ,Protein degradation ,Ligands ,01 natural sciences ,Biochemistry ,Cell Line ,03 medical and health sciences ,Structure-Activity Relationship ,Leucine ,Drug Discovery ,Organometallic Compounds ,Humans ,Histidine ,Molecular Biology ,chemistry.chemical_classification ,biology ,Dose-Response Relationship, Drug ,Molecular Structure ,010405 organic chemistry ,Binding protein ,Organic Chemistry ,Ligand (biochemistry) ,0104 chemical sciences ,Ubiquitin ligase ,030104 developmental biology ,chemistry ,biology.protein ,Cell-penetrating peptide ,Molecular Medicine ,Target protein ,Oligopeptides ,Protein ligand - Abstract
We designed and synthesized hybrid molecules for a protein knockdown method based on the recognition of a His-tag fused to a protein of interest (POI). The synthesized target protein degradation inducers contained three functional moieties: a His-tag ligand (nickel nitrilotriacetic acid [Ni-NTA]), an E3 ligand (bestatin [BS] or MV1), and a carrier peptide (Tat or nonaarginine [R9]). The designed hybrid molecules, BS-Tat-Ni-NTA, MV1-Tat-Ni-NTA, BS-R9-Ni-NTA, and MV1-R9-Ni-NTA, efficiently degraded His-tagged cellular retinoic acid binding protein 2 via the ubiquitin-proteasome system (UPS). This system will become a useful tool for research into selective protein degradation inducers that act via the UPS.
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- 2017
49. Development of Protein Degradation Inducers of Androgen Receptor by Conjugation of Androgen Receptor Ligands and Inhibitor of Apoptosis Protein Ligands
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Osamu Sano, Ryokichi Koyama, Osamu Ujikawa, Yoko Morita, Hiroshi Nara, Nobumichi Ohoka, Norihito Shibata, Mikihiko Naito, Takayuki Hattori, Nobuo Cho, Katsunori Nagai, and Yasuhiro Imaeda
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0301 basic medicine ,Male ,Antineoplastic Agents ,Chemistry Techniques, Synthetic ,Protein degradation ,Inhibitor of apoptosis ,Ligands ,Inhibitor of Apoptosis Proteins ,03 medical and health sciences ,Prostate cancer ,Structure-Activity Relationship ,Ubiquitin ,Cell Line, Tumor ,Drug Discovery ,medicine ,Humans ,Receptor ,Cell Proliferation ,biology ,Chemistry ,Prostatic Neoplasms ,medicine.disease ,Molecular biology ,Cell biology ,Androgen receptor ,030104 developmental biology ,Apoptosis ,A549 Cells ,Receptors, Androgen ,Proteolysis ,biology.protein ,Molecular Medicine ,Drug Screening Assays, Antitumor ,Protein ligand - Abstract
Targeted protein degradation using small molecules is a novel strategy for drug development. We have developed hybrid molecules named specific and nongenetic inhibitor of apoptosis protein [IAP]-dependent protein erasers (SNIPERs) that recruit IAP ubiquitin ligases to degrade target proteins. Here, we show novel SNIPERs capable of inducing proteasomal degradation of the androgen receptor (AR). Through derivatization of the SNIPER(AR) molecule at the AR ligand and IAP ligand and linker, we developed 42a (SNIPER(AR)-51), which shows effective protein knockdown activity against AR. Consistent with the degradation of the AR protein, 42a inhibits AR-mediated gene expression and proliferation of androgen-dependent prostate cancer cells. In addition, 42a efficiently induces caspase activation and apoptosis in prostate cancer cells, which was not observed in the cells treated with AR antagonists. These results suggest that SNIPER(AR)s could be leads for an anticancer drug against prostate cancers that exhibit AR-dependent proliferation.
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- 2017
50. Development of protein degradation inducers of oncogenic BCR-ABL protein by conjugation of ABL kinase inhibitors and IAP ligands
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Kenichiro Shimokawa, Hiroshi Nara, Naoki Miyamoto, Takayuki Hattori, Mikihiko Naito, Tomoya Sameshima, Nobuo Cho, Norihito Shibata, Katsunori Nagai, Yasuhiro Imaeda, and Nobumichi Ohoka
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0301 basic medicine ,Cancer Research ,Cell Survival ,Dasatinib ,Fusion Proteins, bcr-abl ,Down-Regulation ,Protein degradation ,Inhibitor of apoptosis ,Ligands ,Proto-Oncogene Mas ,Inhibitor of Apoptosis Proteins ,03 medical and health sciences ,hemic and lymphatic diseases ,Cell Line, Tumor ,medicine ,Humans ,BCR‐ABL ,Phosphorylation ,neoplasms ,Protein Kinase Inhibitors ,Cell Proliferation ,ABL ,Chemistry ,Ubiquitination ,General Medicine ,Original Articles ,medicine.disease ,Fusion protein ,XIAP ,CRKL ,Gene Expression Regulation, Neoplastic ,Thiazoles ,030104 developmental biology ,Drug Discovery and Delivery ,Oncology ,E3 ubiquitin ligase ,Proteolysis ,Cancer research ,Original Article ,LCL161 ,protein knockdown ,K562 Cells ,Chronic myelogenous leukemia ,medicine.drug ,Protein Binding - Abstract
Chromosomal translocation occurs in some cancer cells, which results in the expression of aberrant oncogenic fusion proteins that include BCR-ABL in chronic myelogenous leukemia (CML). Inhibitors of ABL tyrosine kinase, such as imatinib and dasatinib, exhibit remarkable therapeutic effects, although emergence of drug resistance hampers the therapy during long-term treatment. An alternative approach to treat CML is to downregulate the BCR-ABL protein. We have devised a protein knockdown system by hybrid molecules named Specific and Non-genetic inhibitor of apoptosis protein [IAP]-dependent Protein Erasers (SNIPER), which is designed to induce IAP-mediated ubiquitylation and proteasomal degradation of target proteins, and a couple of SNIPER(ABL) against BCR-ABL protein have been developed recently. In this study, we tested various combinations of ABL inhibitors and IAP ligands, and the linker was optimized for protein knockdown activity of SNIPER(ABL). The resulting SNIPER(ABL)-39, in which dasatinib is conjugated to an IAP ligand LCL161 derivative by polyethylene glycol (PEG) × 3 linker, shows a potent activity to degrade the BCR-ABL protein. Mechanistic analysis suggested that both cellular inhibitor of apoptosis protein 1 (cIAP1) and X-linked inhibitor of apoptosis protein (XIAP) play a role in the degradation of BCR-ABL protein. Consistent with the degradation of BCR-ABL protein, the SNIPER(ABL)-39 inhibited the phosphorylation of signal transducer and activator of transcription 5 (STAT5) and Crk like proto-oncogene (CrkL), and suppressed the growth of BCR-ABL-positive CML cells. These results suggest that SNIPER(ABL)-39 could be a candidate for a degradation-based novel anti-cancer drug against BCR-ABL-positive CML.
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- 2017
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