Browsing by Author "Yokota, Hiroki"
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Item Anticancer Peptides Derived from Aldolase A and Induced Tumor-Suppressing Cells Inhibit Pancreatic Ductal Adenocarcinoma Cells(MDPI, 2023-10-11) Cui, Changpeng; Huo, Qingji; Xiong, Xue; Li, Kexin; Fishel, Melissa L.; Li, Baiyan; Yokota, Hiroki; Biomedical Engineering, School of Engineering and TechnologyPDAC (pancreatic ductal adenocarcinoma) is a highly aggressive malignant tumor. We have previously developed induced tumor-suppressing cells (iTSCs) that secrete a group of tumor-suppressing proteins. Here, we examined a unique procedure to identify anticancer peptides (ACPs), using trypsin-digested iTSCs-derived protein fragments. Among the 10 ACP candidates, P04 (IGEHTPSALAIMENANVLAR) presented the most efficient anti-PDAC activities. P04 was derived from aldolase A (ALDOA), a glycolytic enzyme. Extracellular ALDOA, as well as P04, was predicted to interact with epidermal growth factor receptor (EGFR), and P04 downregulated oncoproteins such as Snail and Src. Importantly, P04 has no inhibitory effect on mesenchymal stem cells (MSCs). We also generated iTSCs by overexpressing ALDOA in MSCs and peripheral blood mononuclear cells (PBMCs). iTSC-derived conditioned medium (CM) inhibited the progression of PDAC cells as well as PDAC tissue fragments. The inhibitory effect of P04 was additive to that of CM and chemotherapeutic drugs such as 5-Flu and gemcitabine. Notably, applying mechanical vibration to PBMCs elevated ALDOA and converted PBMCs into iTSCs. Collectively, this study presented a unique procedure for selecting anticancer P04 from ALDOA in an iTSCs-derived proteome for the treatment of PDAC.Item Anticancer peptides from induced tumor-suppressing cells for inhibiting osteosarcoma cells(e-Century, 2023-09-15) Cui, Chang-Peng; Huo, Qing-Ji; Xiong, Xue; Li, Ke-Xin; Ma, Peng; Qiang, Gui-Fen; Pandya, Pankita H.; Saadatzadeh, Mohammad R.; Vishehsaraei, Khadijeh Bijangi; Kacena, Melissa A.; Aryal, Uma K.; Pollok, Karen E.; Li, Bai-Yan; Yokota, Hiroki; Biomedical Engineering, School of Engineering and TechnologyOsteosarcoma (OS) is the most frequent primary bone cancer, which is mainly suffered by children and young adults. While the current surgical treatment combined with chemotherapy is effective for the early stage of OS, advanced OS preferentially metastasizes to the lung and is difficult to treat. Here, we examined the efficacy of ten anti-OS peptide candidates from a trypsin-digested conditioned medium that was derived from the secretome of induced tumor-suppressing cells (iTSCs). Using OS cell lines, the antitumor capabilities of the peptide candidates were evaluated by assaying the alterations in metabolic activities, proliferation, motility, and invasion of OS cells. Among ten candidates, peptide P05 (ADDGRPFPQVIK), a fragment of aldolase A (ALDOA), presented the most potent OS-suppressing capabilities. Its efficacy was additive with standard-of-care chemotherapeutic agents such as cisplatin and doxorubicin, and it downregulated oncoproteins such as epidermal growth factor receptor (EGFR), Snail, and Src in OS cells. Interestingly, P05 did not present inhibitory effects on non-OS skeletal cells such as mesenchymal stem cells and osteoblast cells. Collectively, this study demonstrated that iTSC-derived secretomes may provide a source for identifying anticancer peptides, and P05 may warrant further evaluations for the treatment of OS.Item Application of pulse width modulation to a Western blotting device(2016) TruongVo, ThucNhi; Yokota, HirokiOne of the critical steps in a current Western blot technique is a blotting process, which in general requires one electrophoretic gel for every protein species to be analyzed. In most cases, multiple protein species are analyzed simultaneously and thus it is necessary for a scientist to run multiple gels. In order to make it possible to analyze multiple protein species from a single gel, a novel blotting device, BlotMan, was employed in this study. Designed by Dr. Chien’s group (YC Bioelectric), BlotMan uses pulse width modulation (PWM) for applying a protein size-dependent voltage during a blotting process. In this study, the differential average voltage profile, depending on protein size (e.g. 17 kDa to 140 kDa), was built and enabled BlotMan to transfer all protein species in equal efficiency regardless of the protein size. Furthermore, Blot- Man consists of a user-friendly, custom-made interface box, which can be remotely controlled by a smart phone. BlotMan’s capability was evaluated using standard protein markers, as well as protein samples that were isolated from chondrosarcoma cells (SW1353) and breast cancer cells (MDA-MB-213). The experimental results revealed that BlotMan was capable of generating 5 blotting membranes from a single gel simultaneously. Protein species such as c-Src, eukaryotic translation initiation factor 2 alpha (eIF2α) and its phosphorylated form (p-eIF2α), lamin B, and β-actin were successfully detected. It is also demonstrated that compared to a regular constant voltage, PWM signals improved transfer efficiency and a signal-to-noise ratio. In conclusion, this study demonstrated that BlotMan was able to facilitate Western blotting analysis by generating multiple blotting membranes from a single gel with an improved signal-to-noise ratio. Further analysis is recommended for understanding the mechanism of PWMts action on transfer efficiency and noise reduction.Item Application of Salubrinal for Bone Fracture Healing(Office of the Vice Chancellor for Research, 2014-04-11) Yokota, Hiroki; Lin, Chien-ChiThe long-term objective of this project is to commercialize a novel synthetic chemical agent, salubrinal, for treatment of bone growth and fracture healing. Bone morphogenetic proteins (BMPs) are clinically administered as growth stimulators for bone fracture healing. However, BMPs are not only expensive, but also stimulate ectopic bone formation and potentially induce cancer. A synthetic chemical agent that permits facile storage and administration could reduce costs, and provide longer shelf-life, and better bone healing outcomes. Currently, no synthetic chemical agents as a stimulator of fracture healing are clinically available. The research team recently identified “salubrinal,” a synthetic chemical agent, as a potential therapeutic stimulator of bone growth and fracture healing. An invention disclosure and a U.S. patent were filed. In this FORCES project, we are examining efficacy of salubrinal using a mouse model of closed tibia fracture. The results strongly indicate that salubrinal can accelerate bone fracture healing.Item Artificial ants deposit pheromone to search for regulatory DNA elements(BioMed Central, 2006-08-30) Liu, Yunlong; Yokota, Hiroki; Medicine, School of MedicineBackground Identification of transcription-factor binding motifs (DNA sequences) can be formulated as a combinatorial problem, where an efficient algorithm is indispensable to predict the role of multiple binding motifs. An ant algorithm is a biology-inspired computational technique, through which a combinatorial problem is solved by mimicking the behavior of social insects such as ants. We developed a unique version of ant algorithms to select a set of binding motifs by considering a potential contribution of each of all random DNA sequences of 4- to 7-bp in length. Results Human chondrogenesis was used as a model system. The results revealed that the ant algorithm was able to identify biologically known binding motifs in chondrogenesis such as AP-1, NFκB, and sox9. Some of the predicted motifs were identical to those previously derived with the genetic algorithm. Unlike the genetic algorithm, however, the ant algorithm was able to evaluate a contribution of individual binding motifs as a spectrum of distributed information and predict core consensus motifs from a wider DNA pool. Conclusion The ant algorithm offers an efficient, reproducible procedure to predict a role of individual transcription-factor binding motifs using a unique definition of artificial ants.Item Attraction and Compaction of Migratory Breast Cancer Cells by Bone Matrix Proteins through Tumor-Osteocyte Interactions(Nature Publishing Group, 2018-04-03) Chen, Andy; Wang, Luqi; Liu, Shengzhi; Wang, Yue; Liu, Yunlong; Wang, Mu; Nakshatri, Harikrishna; Li, Bai-Yan; Yokota, Hiroki; Biomedical Engineering, School of Engineering and TechnologyBone is a frequent site of metastasis from breast cancer. To understand the potential role of osteocytes in bone metastasis, we investigated tumor-osteocyte interactions using two cell lines derived from the MDA-MB-231 breast cancer cells, primary breast cancer cells, and MLO-A5/MLO-Y4 osteocyte cells. When three-dimensional (3D) tumor spheroids were grown with osteocyte spheroids, tumor spheroids fused with osteocyte spheroids and shrank. This size reduction was also observed when tumor spheroids were exposed to conditioned medium isolated from osteocyte cells. Mass spectrometry-based analysis predicted that several bone matrix proteins (e.g., collagen, biglycan) in conditioned medium could be responsible for tumor shrinkage. The osteocyte-driven shrinkage was mimicked by type I collagen, the most abundant organic component in bone, but not by hydroxyapatite, a major inorganic component in bone. RNA and protein expression analysis revealed that tumor-osteocyte interactions downregulated Snail, a transcription factor involved in epithelial-to-mesenchymal transition (EMT). An agarose bead assay showed that bone matrix proteins act as a tumor attractant. Collectively, the study herein demonstrates that osteocytes attract and compact migratory breast cancer cells through bone matrix proteins, suppress tumor migration, by Snail downregulation, and promote subsequent metastatic colonization.Item Author Correction: Inhibitory effects of dopamine receptor D1 agonist on mammary tumor and bone metastasis(Springer Nature, 2022-11-03) Minami, Kazumasa; Liu, Shengzhi; Liu, Yang; Chen, Andy; Wan, Qiaoqiao; Na, Sungsoo; Li, Bai‑Yan; Matsuura, Nariaki; Koizumi, Masahiko; Yin, Yukun; Gan, Liangying; Xu, Aihua; Li, Jiliang; Nakshatri, Harikrishna; Yokota, Hiroki; Biomedical Engineering, School of Engineering and TechnologyThis corrects the article "Inhibitory Effects of Dopamine Receptor D1 Agonist on Mammary Tumor and Bone Metastasis" in volume 7, 45686. doi: 10.1038/srep45686Item Biomechanics and Biomaterials Research Center(Office of the Vice Chancellor for Research, 2013-04-05) Yokota, Hiroki; Xie, DongThe Biomechanics and Biomaterials Research Center (BBRC) was founded in 1991 and reactivated in the current form in 2012. Through a collaborative effort from School of Engineering and Technology, School of Dentistry, School of Medicine, School of Science, and School of Health and Rehabilitation Sciences, the Center is to strengthen a national presence in the emerging areas of Mechanobiology, Tissue Engineering, and Biomaterials. The main aim of BBRC is to enhance our competitiveness for research grants by fostering new research collaborations among established investigators as well as new investigators. In particular, we coordinate efforts to obtain multi-PI research grants from federal agencies including NIH, NSF, NASA, and DOD, as well as center grants, and training programs. Funds at BBRC are used to seed pilot projects, support students, provide shared equipment, and invite seminar speakers for developing multidisciplinary and multi-school research programs. The following pilot projects were funded (95K in total) in 2013. • Development of NIAMS P30 • Development of novel oral stable dental resin composite • FRET-based analysis of mechanotransduction of joint cells • Stat3 and mitochondrial activity in mechanotransduction • Synthetic niche for in vitro culture of pancreatic cancer cells • Mechanical stimulation, fracture resistance and fracture healing in bone • Integration of spatial and temporal respiratory motion in adaptive proton therapy deliveryItem Bone disease in the field of CKD-MBD(2016) Yajima, Aiji; Tsuchiya, Ken; Yokota, Hiroki; Nitta, Kosaku; Anatomy and Cell Biology, School of MedicineThe pathophysiology and treatment for renal bone disease have made remakable progress. Moreover, osteocyte reseach has made tremendous progress. In the clinical aspect, (1) hyperphosphatemia, (2) hyperparathyroid and hypoparathyroid bone disease in patients with chronic kidney disease, (3) increased serum level of fibroblast growth factor 23 (FGF-23) and(4) reduced level of Klotho should be taken into consideration when analyzing these conditions. On the other hand, hyperphosphatemia must be successfully treated. Hyperparathyroid bone disease has been successfully treated with vitamin D sterol, cinacalcet hydrochloride and parathyroidectomy, however, the treatment of hypoparathyroidism inpatient with diabetes or non-diabetes met with high hurdles. We must treat these patients in thinking about osteocytic perilacunar/canalicular system.Item A Brief Review of Bone Adaptation to Unloading.(Elsevier, 2008) Zhang, Ping; Hamamura, Kazunori; Yokota, Hiroki; Department of Biomedical Engineering, School of Engineering and TechnologyWeight-bearing bone is constantly adapting its structure and function to mechanical environments. Loading through routine exercises stimulates bone formation and prevents bone loss, but unloading through bed rest and cast immobilization as well as exposure to weightlessness during spaceflight reduces its mass and strength. In order to elucidate the mechanism underlying unloading-driven bone adaptation, ground-based in vitro and in vivo analyses have been conducted using rotating cell culturing and hindlimb suspension. Focusing on gene expression studies in osteoblasts and hindlimb suspension studies, this minireview introduces our recent understanding on bone homeostasis under weightlessness in space. Most of the existing data indicate that unloading has the opposite effects to loading through common signaling pathways. However, a question remains as to whether any pathway unique to unloading (and not to loading) may exist.