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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 Effects of a checkpoint kinase inhibitor, AZD7762, on tumor suppression and bone remodeling(Spandidos Publications, 2018-09) Wang, Luqi; Wang, Yue; Chen, Andy; Jalali, Aydin; Liu, Shengzhi; Guo, Yunxia; Na, Sungsoo; Nakshatri, Harikrishna; Li, Bai-Yan; Yokota, Hiroki; Biomedical Engineering, School of Engineering and TechnologyChemotherapy for suppressing tumor growth and metastasis tends to induce various effects on other organs. Using AZD7762, an inhibitor of checkpoint kinase (Chk) 1 and 2, the present study examined its effect on mammary tumor cells in addition to bone cells (osteoclasts, osteoblasts and osteocytes), using monolayer cell cultures and three-dimensional (3D) cell spheroids. The results revealed that AZD7762 blocked the proliferation of 4T1.2 mammary tumor cells and suppressed the development of RAW264.7 pre-osteoclast cells by downregulating nuclear factor of activated T cells cytoplasmic 1. AZD7762 also promoted the mineralization of MC3T3 osteoblast-like cells and 3D bio-printed bone constructs of MLO-A5 osteocyte spheroids. While a Chk1 inhibitor, PD407824, suppressed the proliferation of tumor cells and the differentiation of pre-osteoclasts, its effect on gene expression in osteoblasts was markedly different compared with AZD7762. Western blotting indicated that the stimulating effect of AZD7762 on osteoblast development was associated with the inhibition of Chk2 and the downregulation of cellular tumor antigen p53. The results of the present study indicated that in addition to acting as a tumor suppressor, AZD7762 may prevent bone loss by inhibiting osteoclastogenesis and stimulating osteoblast mineralization.Item Effects of salubrinal on development of osteoclasts and osteoblasts from bone marrow-derived cells(Springer Nature, 2013-07-01) Yokota, Hiroki; Hamamura, Kazunori; Chen, Andy; Dodge, Todd R.; Tanjung, Nancy; Abedinpoor, Aysan; Zhang, Ping; Anatomy, Cell Biology and Physiology, School of MedicineBackground: Osteoporosis is a skeletal disease leading to an increased risk of bone fracture. Using a mouse osteoporosis model induced by administration of a receptor activator of nuclear factor kappa-B ligand (RANKL), salubrinal was recently reported as a potential therapeutic agent. To evaluate the role of salubrinal in cellular fates as well as migratory and adhesive functions of osteoclast/osteoblast precursors, we examined the development of primary bone marrow-derived cells in the presence and absence of salubrinal. We addressed a question: are salubrinal's actions more potent to the cells isolated from the osteoporotic mice than those isolated from the control mice? Methods: Using the RANKL-injected and control mice, bone marrow-derived cells were harvested. Osteoclastogenesis was induced by macrophage-colony stimulating factor and RANKL, while osteoblastogenesis was driven by dexamethasone, ascorbic acid, and β-glycerophosphate. Results: The results revealed that salubrinal suppressed the numbers of colony forming-unit (CFU)-granulocyte/macrophages and CFU-macrophages, as well as formation of mature osteoclasts in a dosage-dependent manner. Salubrinal also suppressed migration and adhesion of pre-osteoclasts and increased the number of CFU-osteoblasts. Salubrinal was more effective in exerting its effects in the cells isolated from the RANKL-injected mice than the control. Consistent with cellular fates and functions, salubrinal reduced the expression of nuclear factor of activated T cells c1 (NFATc1) as well as tartrate-resistant acid phosphatase. Conclusions: The results support the notion that salubrinal exhibits significant inhibition of osteoclastogenesis as well as stimulation of osteoblastogenesis in bone marrow-derived cells, and its efficacy is enhanced in the cells harvested from the osteoporotic bone samples.Item Electrical Stimulation Generates Induced Tumor-Suppressing Cells, Offering a Potential Option for Combatting Breast Cancer and Bone Metastasis(MDPI, 2025-01-25) Cui, Changpeng; Xu, Yinzhi; Xiong, Xue; Aryal, Uma K.; Chen, Andy; Chien, Stanley; You, Lidan; Li, Baiyan; Yokota, Hiroki; Medical and Molecular Genetics, School of MedicineTreating advanced metastatic cancer, particularly with bone metastasis, remains a significant challenge. In previous studies, induced tumor-suppressing (iTS) cells were successfully generated through genetic, chemical, and mechanical interventions. This study investigates the potential of electrical stimulation to generate iTS cells. Using a custom electrical stimulator with platinum electrodes, mesenchymal stem cells (MSCs) and Jurkat T cells were stimulated under optimized conditions (50 mV/cm, 10-100 Hz, 1 h). Conditioned medium (CM) from electrically stimulated cells demonstrated tumor-suppressing capabilities, inhibiting tumor cell migration, 3D spheroid growth, and cancer tissue fragment viability. Additionally, the CM reduced osteoclast maturation while promoting osteoblast differentiation. Proteomic analysis revealed enrichment of tumor-suppressing proteins, including histone H4, in the CM. Functional studies identified Piezo1 as a key mediator, as its knockdown significantly impaired the tumor-suppressive effects. Mechanistically, the process was distinct from other methods, such as mechanical vibration, with SUN1 inhibition showing no effect on iTS cell generation by electrical stimulation. These findings demonstrate the efficacy of electrical stimulation in enhancing the antitumor capabilities of MSCs and T cells, offering a novel approach to cancer therapy. Further exploration of this strategy could provide valuable insights into developing new treatments for metastatic cancer.Item Enhancement of osteoblastogenesis and suppression of osteoclastogenesis by inhibition of de-phosphorylation of eukaryotic translation initiation factor 2 alpha(Smart Science and Technology, LLC, 2015) Hamamura, Kazunori; Chen, Andy; Yokota, Hiroki; Department of Anatomy and Cell Biology, IU School of MedicineThe phosphorylation of eukaryotic translation initiation factor 2 alpha (eIF2α) is activated in response to various stresses such as viral infection, nutrient deprivation, and stress to the endoplasmic reticulum. Severe stress to the endoplasmic reticulum, for instance, induces an apoptotic pathway, while mild stress, on the contrary, leads to a pro-survival pathway. Little has been known about the elaborate role of eIF2α phosphorylation in the development of bone-forming osteoblasts and bone-resorbing osteoclasts. Using salubrinal and guanabenz as inhibitors of the de-phosphorylation of eIF2α, we have recently reported that the phosphorylation of eIF2α significantly alters fates of both osteoblasts and osteoclasts. Based on our recent findings, we review in this research highlight the potential mechanisms of the enhancement of osteoblastogenesis and the suppression of osteoclastogenesis through the elevated level of phosphorylated eIF2α.Item Enhancing anti-tumor potential: low-intensity vibration suppresses osteosarcoma progression and augments MSCs' tumor-suppressive abilities(Ivyspring, 2024-01-27) Xiong, Xue; Huo, Qingji; Li, Kexin; Cui, Changpeng; Chang, Chunyi; Park, Charles; Ku, BonHeon; Hong, Chin-Suk; Lim, HeeChang; Pandya, Pankita H.; Saadatzadeh, M. Reza; Bijangi-Vishehsaraei, Khadijeh; Lin, Chien-Chi; Kacena, Melissa A.; Pollok, Karen E.; Chen, Andy; Liu, Jing; Thompson, William R.; Li, Xue-Lian; Li, Bai-Yan; Yokota, Hiroki; Anatomy, Cell Biology and Physiology, School of MedicineRationale: Osteosarcoma (OS), a common malignant bone tumor, calls for the investigation of novel treatment strategies. Low-intensity vibration (LIV) presents itself as a promising option, given its potential to enhance bone health and decrease cancer susceptibility. This research delves into the effects of LIV on OS cells and mesenchymal stem cells (MSCs), with a primary focus on generating induced tumor-suppressing cells (iTSCs) and tumor-suppressive conditioned medium (CM). Methods: To ascertain the influence of vibration frequency, we employed numerical simulations and conducted experiments to determine the most effective LIV conditions. Subsequently, we generated iTSCs and CM through LIV exposure and assessed the impact of CM on OS cells. We also explored the underlying mechanisms of the tumor-suppressive effects of LIV-treated MSC CM, with a specific focus on vinculin (VCL). We employed cytokine array, RNA sequencing, and Western blot techniques to investigate alterations in cytokine profiles, transcriptomes, and tumor suppressor proteins. Results: Numerical simulations validated LIV frequencies within the 10-100 Hz range. LIV induced notable morphological changes in OS cells and MSCs, confirming its dual role in inhibiting OS cell progression and promoting MSC conversion into iTSCs. Upregulated VCL expression enhanced MSC responsiveness to LIV, significantly bolstering CM's efficacy. Notably, we identified tumor suppressor proteins in LIV-treated CM, including procollagen C endopeptidase enhancer (PCOLCE), histone H4 (H4), peptidylprolyl isomerase B (PPIB), and aldolase A (ALDOA). Consistently, cytokine levels decreased significantly in LIV-treated mouse femurs, and oncogenic transcript levels were downregulated in LIV-treated OS cells. Moreover, our study demonstrated that combining LIV-treated MSC CM with chemotherapy drugs yielded additive anti-tumor effects. Conclusions: LIV effectively impeded the progression of OS cells and facilitated the transformation of MSCs into iTSCs. Notably, iTSC-derived CM demonstrated robust anti-tumor properties and the augmentation of MSC responsiveness to LIV via VCL. Furthermore, the enrichment of tumor suppressor proteins within LIV-treated MSC CM and the reduction of cytokines within LIV-treated isolated bone underscore the pivotal tumor-suppressive role of LIV within the bone tumor microenvironment.Item Enhancing anti-tumor potential: low-intensity vibration suppresses osteosarcoma progression and augments MSCs' tumor-suppressive abilities(2024) Xiong, Xue; Huo, Qingji; Li, Kexin; Cui, Changpeng; Chang, Chunyi; Park, Charles; Ku, BonHeon; Hong, Chin-Suk; Lim, HeeChang; Pandya, Pankita H.; Saadatzadeh, M. Reza; Bijangi-Vishehsaraei, Khadijeh; Lin, Chien-Chi; Kacena, Melissa A.; Pollok, Karen E.; Chen, Andy; Liu, Jing; Thompson, William R.; Li, Xue-Lian; Li, Bai-Yan; Yokota, Hiroki; Health Sciences, School of Health and Human SciencesRationale: Osteosarcoma (OS), a common malignant bone tumor, calls for the investigation of novel treatment strategies. Low-intensity vibration (LIV) presents itself as a promising option, given its potential to enhance bone health and decrease cancer susceptibility. This research delves into the effects of LIV on OS cells and mesenchymal stem cells (MSCs), with a primary focus on generating induced tumor-suppressing cells (iTSCs) and tumor-suppressive conditioned medium (CM). Methods: To ascertain the influence of vibration frequency, we employed numerical simulations and conducted experiments to determine the most effective LIV conditions. Subsequently, we generated iTSCs and CM through LIV exposure and assessed the impact of CM on OS cells. We also explored the underlying mechanisms of the tumor-suppressive effects of LIV-treated MSC CM, with a specific focus on vinculin (VCL). We employed cytokine array, RNA sequencing, and Western blot techniques to investigate alterations in cytokine profiles, transcriptomes, and tumor suppressor proteins. Results: Numerical simulations validated LIV frequencies within the 10-100 Hz range. LIV induced notable morphological changes in OS cells and MSCs, confirming its dual role in inhibiting OS cell progression and promoting MSC conversion into iTSCs. Upregulated VCL expression enhanced MSC responsiveness to LIV, significantly bolstering CM's efficacy. Notably, we identified tumor suppressor proteins in LIV-treated CM, including procollagen C endopeptidase enhancer (PCOLCE), histone H4 (H4), peptidylprolyl isomerase B (PPIB), and aldolase A (ALDOA). Consistently, cytokine levels decreased significantly in LIV-treated mouse femurs, and oncogenic transcript levels were downregulated in LIV-treated OS cells. Moreover, our study demonstrated that combining LIV-treated MSC CM with chemotherapy drugs yielded additive anti-tumor effects. Conclusions: LIV effectively impeded the progression of OS cells and facilitated the transformation of MSCs into iTSCs. Notably, iTSC-derived CM demonstrated robust anti-tumor properties and the augmentation of MSC responsiveness to LIV via VCL. Furthermore, the enrichment of tumor suppressor proteins within LIV-treated MSC CM and the reduction of cytokines within LIV-treated isolated bone underscore the pivotal tumor-suppressive role of LIV within the bone tumor microenvironment.Item Finite Element Analysis of the Mouse Distal Femur with Tumor Burden in Response to Knee Loading(Medip Academy, 2018) Jiang, Feifei; Liu, Shengzhi; Chen, Andy; Li, Bai-Yan; Robling, Alexander G.; Chen, Jie; Yokota, Hiroki; Mechanical and Energy Engineering, School of Engineering and TechnologyBreast cancer-associated bone metastasis induces bone loss, followed by an increased risk of bone fracture. To develop a strategy for preventing tumor growth and protecting bone, an understanding of the mechanical properties of bone under tumor burden is indispensable. Using a mouse model of mammary tumor, we conducted finite element analysis (FEA) of two bone samples from the distal femur. One sample was from a placebo-treated mouse, and the other was from a mouse treated with the investigational drug candidate, PD407824, an inhibitor of checkpoint kinases. Mechanical testing and microCT images revealed that bone strength is improved by administration of PD407824. In response to loading to the knee, FEA predicted that the peaks of von Mises stress, an indicator of fracture yielding, as well as the third principal compressive stress, were higher in the placebo-treated femur than the drug-treated femur. Higher peak stresses in trabecular segments were observed in the lateral condyle, a critical region for integrity of the knee joint. Collectively, this FE study supports the notion that mechanical weakening of the femur was observed in the tumor-invaded trabecular bone, and chemical agents such as PD407824 may potentially assist in preventing bone loss and bone fracture.Item Finite Element Analysis of the Mouse Proximal Ulna in Response to Elbow Loading(Springer, 2018) Jiang, Feifei; Jalali, Aydin; Deguchi, Chie; Chen, Andy; Liu, Shengzhi; Kondo, Rika; Minami, Kazumasa; Horiuchi, Takashi; Li, Bai-Yan; Robling, Alexander G.; Chen, Jie; Yokota, Hiroki; Mechanical and Energy Engineering, School of Engineering and TechnologyBone is a mechano-sensitive tissue that alters its structure and properties in response to mechanical loading. We have previously shown that application of lateral dynamic loads to a synovial joint, such as the knee and elbow, suppresses degradation of cartilage and prevents bone loss in arthritis and postmenopausal mouse models, respectively. While loading effects on pathophysiology have been reported, mechanical effects on the loaded joint are not fully understood. Because the direction of joint loading is non-axial, not commonly observed in daily activities, strain distributions in the laterally loaded joint are of great interest. Using elbow loading, we herein characterized mechanical responses in the loaded ulna focusing on the distribution of compressive strain. In response to 1-N peak-to-peak loads, which elevate bone mineral density and bone volume in the proximal ulna in vivo, we conducted finite-element analysis and evaluated strain magnitude in three loading conditions. The results revealed that strain of ~ 1000 μstrain (equivalent to 0.1% compression) or above was observed in the limited region near the loading site, indicating that the minimum effective strain for bone formation is smaller with elbow loading than axial loading. Calcein staining indicated that elbow loading increased bone formation in the regions predicted to undergo higher strain.
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