scholarly journals Bone formation around unstable implants is enhanced by a WNT protein therapeutic in a preclinical in vivo model

2020 ◽  
Vol 31 (11) ◽  
pp. 1125-1137
Author(s):  
Benjamin R. Coyac ◽  
Brian Leahy ◽  
Zhijun Li ◽  
Giuseppe Salvi ◽  
Xing Yin ◽  
...  
Keyword(s):  
Bone Formation ◽  
In Vivo Model ◽  
Protein Therapeutic

Nanoparticle Design For Bone-Specific Chemotherapy and Microenvironmental Targeting In Multiple Myeloma

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 881-881 ◽  
Author(s):  
Michaela R Reagan ◽  
Archana Swami ◽  
Pamela A Basto ◽  
Yuji Mishima ◽  
Jinhe Liu ◽  
...  
Keyword(s):  
Bone Formation ◽  
Tumor Growth ◽  
Board Of Directors ◽  
Bone Cells ◽  
Release Kinetics ◽  
In Vivo Model ◽  
Advisory Committees ◽  
Pre Treatment

Abstract Introduction The bone marrow (BM) niche is known to exert a protective effect on lymphoid tumors, such as multiple myeloma (MM), where mesenchymal stem cell interactions with clonal plasma cells increase tumor proliferation and survival. However, certain cells within the BM milieu, such as mature osteoblasts and osteocytes, have demonstrated the potential to inhibit tumor growth; utilizing these cells presents a promising new anti-cancer approach. Hence, designing better methods of bone-specific delivery for both direct cancer cell treatment and indirect treatment through the modulation of bone cells may result in a potent, two-pronged anti-cancer strategy. Our work aimed to develop a novel system to target both MM and bone cells to induce greater osteogenesis and hamper tumor growth. Methods PEG–PLGA nanoparticles (NPs) coupled to alendronate (“bone-targeted”) or alone (“non-targeted”) were formulated and loaded with bortezomib (“BTZ-NPs”) or left empty (“BTZ-free”). NPs were characterized for their physiochemical properties, including size (using dynamic light scattering; surface charges (Zeta potential); and bone affinity (using hydroxyapatite binding). NPs were engineered with different formulation methods and those with the optimal physiochemical characteristics and drug encapsulation efficiency were used for further studies. BTZ release kinetics were analyzed using HPLC. Anti-MM effects were assessed in vitro using MTT, bioluminescence (BLI) and Annexin V/PI apoptosis flow cytometry analysis on MM1S cells. In vivo, efficacy was measured by mouse weight, BLI and survival after i.v. cancer cell injections in mice. Cellular uptake was assessed in vitro by flow cytometry and in vivo biodistribution was assessed using fluorescent whole body and fixed section imaging. Bone specificity was assessed in vitro by co-culture of bone-targeted and non-targeted NPs with bone chips or hydroxyapatite using fluorescence and TEM imaging. In an in vivo model of myeloma treatment, female Nod/SCID beige mice were injected i.v. with 4 × 106 Luc+/GFP+ MM1S cells and, at day 21, treated with a) BTZ, b) BTZ-bone-targeted NPs, c) BTZ-non-targeted NPs or d) BTZ-free bone-targeted NPs. Using an in vivo model of pre-treatment for cancer prevention, mice were pre-treated with i.p. injections of BTZ-bone-targeted NPs and appropriate controls thrice weekly for 3 weeks. They were then injected i.v. with Luc+/GFP+ 5TGM1 or MM1S cells and monitored for BLI and survival. Static and dynamic bone histomorphometry and μCT were used to assess effects of pre-treatment on bone formation and osteolysis prevention. Results Our biodegradable, NPs had uniform size distribution within the range of 100 to 200 nm based on the type of formulation, with a zeta potential of ±5mV. Bone- targeted NPs showed high affinity towards bone mineral in vitro and better skeletal accumulation in vivo compared to non-targeted NPs. NPs were easily up-taken by cells in vitro, and BTZ release kinetics showed a burst followed by a sustained-release pattern over 60 hrs. BTZ-NPs induced apoptosis in MM cells in vitro. Importantly, BTZ-bone-targeted-NP pre-treated mice showed significantly less tumor burden (BLI) and longer survival than free drug or drug-free bone-targeted NPs, thus demonstrating a tumor-inhibiting effect unique to the BTZ-bone-targeted-NPs. Pre-treatment with BTZ increased bone formation in tibias and femurs, as measured by μCT of bone volume/total volume, and trabecular thickness and number, suggesting that increased bone volume may inhibit MM. In a second mouse model, both BTZ-bone-targeted NPs and BTZ-free NPs were equally able to reduce tumor growth in vivo when given after tumor formation. Conclusion Bone-targeted nanoparticles hold great potential for clinical applications in delivering chemotherapies to bone marrow niches, reducing off-target effects, increasing local drug concentrations, and lengthening the therapeutic window. BTZ-bone-targeted NPs are able to slow tumor growth and increase survival in mice when used as a pre-treatment. This may result, at least in part, from BTZ-induced increased bone formation. These findings indicate that BTZ-bone-targeted NPs exert a chemopreventive effect in MM in vivo, thus suggesting their potential use in the clinical setting. Disclosures: Basto: BIND Therapeutics: Patent licensed by BIND, Patent licensed by BIND Patents & Royalties. Farokhzad:BIND Therapeutics: Employment, Equity Ownership; Selecta Biosciences: Employment, Equity Ownership. Ghobrial:Onyx: Membership on an entity’s Board of Directors or advisory committees; BMS: Membership on an entity’s Board of Directors or advisory committees; BMS: Research Funding; Sanofi: Research Funding; Novartis: Membership on an entity’s Board of Directors or advisory committees.

Preclinical Efficacy of the Investigational Orally Bioavailable Proteasome Inhibitor MLN9708 in Myeloma Bone Disease

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 4014-4014
Author(s):  
Antonio Garcia-Gomez ◽  
Dalia Quwaider ◽  
Enrique M Ocio ◽  
Laura San-Segundo ◽  
Teresa Paíno ◽  
...  
Keyword(s):  
Mouse Model ◽  
Bone Formation ◽  
Proteasome Inhibitor ◽  
Serum Levels ◽  
In Vivo Model ◽  
Healthy Donors ◽  
And Function ◽  
Rpmi 8226

Abstract Abstract 4014 Introduction: Bone destruction, a hallmark of multiple myeloma (MM), arises as a consequence of the interactions between MM cells and the bone marrow microenvironment, which lead to an increase in the bone-resorptive activity and number of osteoclasts (OC) and a reduction of the bone-forming activity and differentiation of osteoblasts (OB). MLN9708, which hydrolyzes to pharmacologically active MLN2238 in aqueous solution, is an investigational proteasome inhibitor (PI) with demonstrated preclinical anti-myeloma activity. However, it is currently not known whether MLN9708, may have a beneficial effect on myeloma-associated bone disease. Here, we have conducted in vitro and in vivo studies to evaluate its ability to promote osteogenic differentiation and to inhibit OC formation and function in the myeloma setting. Patient samples, material and methods: The human MM cell lines RPMI-8226 and MM.1S (or RPMI-8226-luc and MM.1S-luc) together with the mesenchymal stem hMSC-TERT cell line were employed. Also, MSCs from BM samples of healthy donors and MM patients were used in OB differentiation studies, whereas PBMCs from healthy volunteers were used to generate OCs. NOD.SCID.IL2Rγ−/− mice were used in the in vivo model of disseminated human MM. MLN2238 and bortezomib (Velcade) were provided by Millennium Pharmaceuticals, Inc. OB differentiation from MSCs and OB function were investigated by measurement of ALP activity, quantitative mineralization, luciferase reporter assays, siRNA gene silencing and real time RT-PCR. The effect of the new PI on OC formation was assessed by enumeration of multinucleated (≥3) TRAP-positive cells. Measurement of resorbed area, immunofluorescence and flow cytometry were used to further investigate the effect of MLN2238 on OC function. In our in vivo model, bioluminescence imaging, micro-CT analysis and serum levels of Igλ and bone markers were determined. Results: Physiologic concentrations of MLN2238 were able to stimulate the osteogenic differentiation of MSCs from both myeloma patients and healthy donors in vitro to an extent comparable to bortezomib; this was assessed by increased levels of ALP activity, higher expression of bone formation markers (Runx2, osterix, osteopontin and osteocalcin) and augmented matrix mineralization. The enhanced OB formation and function induced by MLN2238 was at least partly due to induction of T-cell factor 4 (TCF4) transcriptional activity, as well as to activation of the unfolded protein response. A similar range of MLN2238 doses also markedly inhibited OC formation and resorption from human progenitors. Similarly to that described with bortezomib, MLN2238 treatment of human pre-OCs prevented RANKL-induced NF-κB activation, disrupted the integrity of the F-actin ring and also reduced the expression of the αVβ3 integrin, thus contributing to inhibition of OC function. MLN2238 was also able to overcome the growth advantage conferred to MM.1S-luc cells by co-culture with MSCs or OCs. Oral administration of MLN2238 in a mouse model of disseminated human MM decreased human RPMI-8226-luc tumor burden as assessed by diminished bioluminescence signal and decreased serum levels of Igλ secreted by RPMI-8226-luc cells. In addition, MLN2238 prevented tumor-associated bone loss with significant increases in femoral trabecular bone parameters as compared to vehicle control animals. Serum markers of bone turnover showed that MLN2238 inhibited bone resorption (decreased levels of CTX) while enhancing bone formation (increased levels of P1NP). Conclusion: MLN2238 in vitro was capable of promoting osteoblastogenesis and OB activity as well as of inhibiting OC formation and function to an extent similar to bortezomib. In a disseminated human MM mouse model, orally administered MLN2238 showed anti-resorptive and bone-anabolic effects in addition to its anti-tumor properties. Given the thus far available data on the preclinical safety and favorable pharmacologic properties of MLN2238, it is conceivable that MLN9708, the clinical formulation of this proteasome inhibitor, may also achieve bone benefits in myeloma patients. Disclosures: Berger: Millennium Pharmaceuticals, Inc.: Employment. San-Miguel:Millennium Pharmaceuticals, Inc.: Consultancy.

scholarly journals Osteogenic Cell Behavior on Titanium Surfaces in Hard Tissue

2019 ◽  
Vol 8 (5) ◽  
pp. 604 ◽  
Author(s):  
Jung-Yoo Choi ◽  
Tomas Albrektsson ◽  
Young-Jun Jeon ◽  
In-Sung Luke Yeo
Keyword(s):  
Electron Microscopy ◽  
Bone Formation ◽  
Dental Implants ◽  
Electron Microscopic Level ◽  
In Vivo Model ◽  
Electron Microscopic ◽  
Implant Surface ◽  
Cell Responses ◽  
Surrounding Bone

It is challenging to remove dental implants once they have been inserted into the bone because it is hard to visualize the actual process of bone formation after implant installation, not to mention the cellular events that occur therein. During bone formation, contact osteogenesis occurs on roughened implant surfaces, while distance osteogenesis occurs on smooth implant surfaces. In the literature, there have been many in vitro model studies of bone formation on simulated dental implants using flattened titanium (Ti) discs; however, the purpose of this study was to identify the in vivo cell responses to the implant surfaces on actual, three-dimensional (3D) dental Ti implants and the surrounding bone in contact with such implants at the electron microscopic level using two different types of implant surfaces. In particular, the different parts of the implant structures were scrutinized. In this study, dental implants were installed in rabbit tibiae. The implants and bone were removed on day 10 and, subsequently, assessed using scanning electron microscopy (SEM), immunofluorescence microscopy (IF), transmission electron microscopy (TEM), focused ion-beam (FIB) system with Cs-corrected TEM (Cs-STEM), and confocal laser scanning microscopy (CLSM)—which were used to determine the implant surface characteristics and to identify the cells according to the different structural parts of the turned and roughened implants. The cell attachment pattern was revealed according to the different structural components of each implant surface and bone. Different cell responses to the implant surfaces and the surrounding bone were attained at an electron microscopic level in an in vivo model. These results shed light on cell behavioral patterns that occur during bone regeneration and could be a guide in the use of electron microscopy for 3D dental implants in an in vivo model.

Mechanical stimulation induces pp125FAK and pp60 src activity in an in vivo model of trabecular bone formation

2001 ◽  
Vol 91 (2) ◽  
pp. 912-918 ◽  
Author(s):  
Maria R. Moalli ◽  
Suquing Wang ◽  
Nancy J. Caldwell ◽  
Pravin V. Patil ◽  
Craig R. Maynard
Keyword(s):  
Bone Formation ◽  
Trabecular Bone ◽  
Mechanical Stimulation ◽  
Time Course ◽  
Mechanical Load ◽  
Compressive Load ◽  
In Vivo Model ◽  
Temporal And Spatial ◽  
N Loading

Utilizing an in vivo model of trabecular bone formation, we demonstrated the temporal and spatial activation of pp125FAK in response to specific mechanical load stimuli. Bone chambers equipped with hydraulic actuators were aseptically inserted into each proximal tibial metaphysis of adult, male dogs under general anesthesia. The load stimulus consisted of a trapezoidal waveform, with a maximum compressive load of 17.8 N, loading rate of 89 N/s, at 1 Hz frequency. One chamber was loaded for 2 (120 cycles), 15 (900 cycles), or 30 min (1,800 cycles), whereas the contralateral chamber served as unloaded control. Bone chambers were biopsied at postload time points of 0, 15, and 45 min. Load-induced activation of FAK was rapid, and the duration of activation was dependent on the number of applied load cycles. Mechanical stimulation increased the association of FAK with Src and the time course of complex formation paralleled the temporal activation of FAK. Evaluation of cryosections revealed prominent FAK immunoreactivity among marrow fibroblasts and stromal cells.

Transforming growth factor β1 stimulates bone formation and resorption in an in-vivo model in rabbits

Bone ◽  
1995 ◽  
Vol 17 (4) ◽  
pp. S443-S448 ◽  
Author(s):  
H. Zhou ◽  
P.C. Choong ◽  
S.T. Chou ◽  
V. Kartsogiannis ◽  
T.J. Martin ◽  
...  
Keyword(s):  
Growth Factor ◽  
Bone Formation ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Β1 ◽  
In Vivo Model

A novel in vivo model to study endochondral bone formation; HIF-1α activation and BMP expression

Bone ◽  
2007 ◽  
Vol 40 (2) ◽  
pp. 409-418 ◽  
Author(s):  
Pieter J. Emans ◽  
Frank Spaapen ◽  
Don A.M. Surtel ◽  
Keryn M. Reilly ◽  
Andy Cremers ◽  
...  
Keyword(s):  
Bone Formation ◽  
In Vivo Model ◽  
Endochondral Bone Formation ◽  
Endochondral Bone

Establishment of an in vivo model for KCNJ5 dependent hyperaldosteronism

2015 ◽  
Vol 122 (03) ◽  
Author(s):  
U Lichtenauer ◽  
PL Schmid ◽  
A Oßwald ◽  
I Renner-Müller ◽  
M Reincke ◽  
...  
Keyword(s):  
In Vivo Model
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