Glioblastoma research on zebrafish xenograft models: a systematic review.

Glioblastoma (GBM) constitutes the most common primary brain tumor in adults. The challenges in GBM therapeutics have shed light on zebrafish used as a promising animal model for preclinical GBM xenograft studies without a standardized methodology. This systematic review aims to summarize the advances in zebrafish GBM xenografting, compare research protocols to pinpoint advantages and underlying limitations, and designate the predominant xenografting parameters. Based on the PRISMA checklist, we systematically searched PubMed, Scopus, and ZFIN using the keywords "glioblastoma," "xenotransplantation," and "zebrafish" for papers published from 2005 to 2022, available in English. 46 articles meeting the review criteria were examined for the zebrafish strain, cancer cell line, cell labeling technique, injected cell number, time and site of injection, and maintenance temperature. Our review designated that AB wild-type zebrafish, Casper transparent mutants, transgenic Tg(fli1:EGFP), or crossbreeding of these predominate among the zebrafish strains. Orthotopic transplantation is more commonly employed. A number of 50-100 cells injected at 48 h post-fertilization in high density and low infusion volume is considered as an effective xenografting approach. U87 cells are used for GBM angiogenesis studies, U251 for GBM proliferation studies, and patient-derived xenograft (PDX) to achieve clinical relevance. Gradual acclimatization to 32-33 °C can partly address the temperature differential between the zebrafish and the GBM cells. Zebrafish xenograft models constitute valuable tools for preclinical studies with clinical relevance regarding PDX. The GBM xenografting research requires modification based on the objective of each research team. Automation and further optimization of the protocol parameters could scale up the anticancer drug trials.

Performance of collagen-based matrices from Nile tilapia skin: A pilot proteomic study in a murine model of wound healing.

Full-thickness cutaneous trauma, due to the lack of dermis, leads to difficulty in epithelialization by keratinocytes, developing a fibrotic scar, with less elasticity than the original skin, which may have disorders in predisposed individuals, resulting in hypertrophic scar and keloids. Biomedical materials have excellent characteristics, such as good biocompatibility and low immunogenicity, which can temporarily replace traditional materials used as primary dressings. In this work, we developed two dermal matrices based on Nile tilapia collagen, with (M_GAG) and without (M) glycosaminoglycans, using a sugarcane polymer membrane as a matrix support. To assess the molecular mechanisms driving wound healing, we performed qualitative proteomic analysis on the wound bed in an in vivo study involving immunocompetent murine models at 14 and 21 days post-full-thickness skin injury. Gene Ontology and Pathway analysis revealed that both skins were markedly represented by modulation of the immune system, emphasizing controlling the acute inflammation response at 14 and 21 days post-injury. Furthermore, both groups showed significant enrichment of pathways related to RNA and protein metabolism, suggesting an increase in protein synthesis required for tissue repair and proper wound closure. Other pathways, such as keratinization and vitamin D3 metabolism, were also enriched in the groups treated with M matrix. Finally, both matrices improved wound healing in a full post-thick skin lesion. However, our preliminary molecular data reveals that the collagen-mediated healing matrix lacking glycosaminoglycan (M) exhibited a phenotype more favorable to tissue repair, making it more suitable for use before skin grafts.

A Comparative Study of HA/DBM Compounds Derived from Bovine and Porcine for Bone Regeneration.

This comparative study investigated the tissue regeneration and inflammatory response induced by xenografts comprised of hydroxyapatite (HA) and demineralized bone matrix (DBM) extracted from porcine (P) and bovine (B) sources. First, extraction of HA and DBM was independently conducted, followed by chemical and morphological characterization. Second, mixtures of HA/DBM were prepared in 50/50 and 60/40 concentrations, and the chemical, morphological, and mechanical properties were evaluated. A rat calvarial defect model was used to evaluate the tissue regeneration and inflammatory responses at 3 and 6 months. The commercial allograft DBM Puros® was used as a clinical reference. Different variables related to tissue regeneration were evaluated, including tissue thickness regeneration (%), amount of regenerated bone area (%), and amount of regenerated collagen area (%). The inflammatory response was evaluated by quantifying the blood vessel area. Overall, tissue regeneration from porcine grafts was superior to bovine. After 3 months of implantation, the tissue thickness regeneration in the 50/50P compound and the commercial DBM was significantly higher (~99%) than in the bovine materials (~23%). The 50/50P and DBM produced higher tissue regeneration than the naturally healed controls. Similar trends were observed for the regenerated bone and collagen areas. The blood vessel area was correlated with tissue regeneration in the first 3 months of evaluation. After 6 months of implantation, HA/DBM compounds showed less regenerated collagen than the DBM-only xenografts. In addition, all animal-derived xenografts improved tissue regeneration compared with the naturally healed defects. No clinical complications associated with any implanted compound were noted.

Current state of clinical trials on xenograft.

BACKGROUND: Xenotransplantation is a worth investing branch of science, since it aims to fulfil the demand on human cells, tissues and organs. Despite decades of consistent work in preclinical assessments, clinical trials on xenotransplantation are far from reaching the targeted goal. Our study aims to track the characteristics, assess the content and summarize the plan of each trial on skin, beta-island, bone marrow, aortic valve and kidney xenografts, leading to a clear sorting of efforts made in this field. METHODS: In December 2022, we searched clinicaltrial.gov for interventional clinical trials related to xenograft of skin, pancreas, bone marrow, aortic valve and kidney. A total of 14 clinical trials are included in this study. Characteristics on each trial were gathered. Linked publications were searched using Medline/PubMed and Embase/Scopus. Content of trials was reviewed and summarized. RESULTS: Only 14 clinical trials met our study's criteria. The majority were completed, and most of the trials' enrolment was between 11 and 50 participants. Nine trials used a xenograft of porcine origin. Six trials targeted skin xenotransplantation, four targeted ß-cells, two targeted bone marrow and one trial targeted each of the kidney and aortic valve. The average length of trials was 3.38 years. Four trials were conducted in the United States and two trials in each of Brazil, Argentina and Sweden. Of all the included trials, none had any results provided and only three had published work. Phases I, III, and IV had only one trial each. A total of 501 participants were enrolled in these trials. CONCLUSION: This study sheds the light on the current state of clinical trials on xenograft. Characteristically, trials on this field are of low number, low enrolment, short duration, few related publications and no published results. Porcine organs are the most used in these trials, and skin is the most studied organ. An extension of the literature is highly needed due to the variety of conflicts mentioned. Overall, this study sheds the light on the necessity of managing research efforts, leading to the initiation of more trials targeting the field of xenotransplantation.

The expression of matrix metalloproteinase-13 (MMP-13) on xenograft and PRF in bone regeneration / Efeito da combinação de xenoenxerto e PRP na expressão de metaloproteinase de matriz -13 (MMP-13) durante regeneração óssea

Objective: inflammation may play a role in bone loss by altering the boné remodelling process, favouring bone resorption by osteoclasts over bone synthesis by osteoblasts. Matrix metalloproteinase 13 (MMP-13) has the ability to activate osteoclasts, leading to bone resorption. Regenerative treatments have been widely used in periodontology. When combined with Platelet-rich fibrin (PRF), xenografts will give better results in bone regeneration. The aim of this study was to evaluate the effect of xenograft combined with PRF on MMP-13 expression in a bone defect using an experimentally created bone defect. Material and Methods: eighteen New Zealand rabbits were assigned to three groups. Each group consisted of six New Zealand rabbits. A critical bone defect with a diameter size of 5 mm was created in the right tibia of each rabbit in group 1 (application: xenograft), group 2 (application: PRF), and group 3 (application: xenograft and PRF). The PRF was produced from 5 ml of blood taken from each rabbit's ears. After 30 days, the rabbits were euthanized. The tissue samples were evaluated by immunohistochemical staining. Results: group 3 showed the lowest mean expression of MMP-13 (4.50) compared to group 1 (20.50) and group 2 (11.70). Group 3 showed a significant difference in the MMP-13 expression compared to group 1 and group 2 (P = 0.000) (P < 0.05). Conclusion: this research showed that the combination of xenograft and PRF had the lowest expression of MMP-13. The application of a xenograft and PRF has better osteogenesis ability in bone regeneration.(AU)

Objetivo: inflamação pode interferir na perda óssea através de alterações no processo de remodelação, favorecendo a reabsorção óssea pelos osteoclastos ao invés da síntese pelos osteoblastos. A metaloproteinases de matriz 13 (MMP-13) ativa osteoclastos causando reabsorção óssea. Tratamentos regenerativos têm sido amplamente usados na periodontia. Quando combinamos Plasma rico em plaquetas (PRP) e xenoenxerto levam a melhores resultados de regeneração óssea. O objetivo deste estudo foi avaliar os efeitos de xenoenxerto combinado com PRP na expressão de MMP-13 em defeitos ósseos experimentais. Material e Métodos: dezoitos coelhos Nova Zelândia foram distribuídos em 3 grupos de 6 coelhos cada. Um defeito ósseo de 5 mm de diâmetro foi feito na tíbia direita dos animais do grupo 1 (xenoenxerto), grupo 2 (PRP) e grupo 3 (Xenoenxerto+PRP). O PRP foi obtido pela coleta de 5mL de sangue das orelhas dos coelhos. Após 30 dias, os coelhos foram eutanasiados. As amostras foram submetidas a coloração imuno-histoquímica. Resultados: o grupo 3 apresentou a menor expressão de MMP-13 (4.50) quando comparado ao grupo 1 (20.50) e ao grupo 2 (11.70). O grupo 3 mostrou diferença estatística significante em relação a expressão de MMP-13 quando comparado aos grupos 1 e 2 (p=0.000) (p< 0.05). Conclusão: esta pesquisa mostra que a combinação de xenoenxerto e PRP teve a menor expressão de MMP-13. A combinação de xenoenxerto e PRP têm maior habilidade de osteogênese na regeneração óssea (AU)

Osteocalcin and Runx2 Expression in Anterior Maxillary Reconstructions Using Bone Xenografts Associated to Bone Marrow Aspirate Concentrate.

Background: It is known that a large number of mediators involved in osteogenesis can influence bone development and repair; however, whether these mediators could be used as markers of bone maturity has yet to be determined. Aim: To evaluate the expression of osteocalcin (OC) and Runt-related transcription factor 2 (Runx2) in bone biopsies obtained during the reconstruction of atrophic anterior maxillae using particulate bone xenografts with or without association of autogenous bone marrow aspirate concentrate (BMAC). Materials and Methods: Ten patients were distributed into two groups (n = 5), according to the type of grafting material used: Control group (CG), particulate bone xenograft alone, and test group (TG), particulate bone xenograft combined with BMAC. A bone specimen was removed from the graft area 4 months after grafting, before implant placement. The specimens were processed and submitted to immunohistochemical analysis for detection of OC and Runx2. Histomorphometry was used to ascertain the percentage of stained areas in both groups. The Wilcoxon Mann-Whitney U-Test was used in the statistical analysis (P < 0.05). Results: The immunohistochemical analysis revealed a significantly higher OC expression in the TG than in the CG, namely 27.40 ± 1.34% and 11.40 ± 2.70%, respectively (P < 0.05), and a significantly higher Runx2 expression in the TG than in the CG, namely 2.80 ± 0.84% and 0.40 ± 0.55%, respectively (P < 0.05). Conclusion: The OC and Runx2 expression levels were higher when BMAC was associated with the bone xenograft than when it was not.

Laddec® versus Bio-Oss®: The effect on the healing of critical-sized defect - Calvaria rabbit model.

The aim of this study was to evaluate the in vivo performance of two different deproteinized bovine bone (DBB) grafting materials: DBBB (Bio-Oss®) and DBBL (Laddec®), for the regeneration of critically sized (8 mm) defects in rabbit's calvaria. Three round-shaped defects were surgically created in the calvaria of 13 New Zealand White rabbits proximal to the coronal suture in the parietal bone. Two of the defects were filled with one of the grafting materials while a third was left empty to serve as a negative control. Bone regeneration properties were evaluated at 4- and 8-weeks after implantation by means of histological and histomorphometrical analyses. Statistical analyses were performed through a mixed model analysis with fixed factors of time and material. Histological evaluation of the control group evidenced a lack of bridging bone formation across the defect sites at both evaluation time points. For the experimental groups, new bone formation was observed around the defect periphery and to progress radially inwards to the center of the defect site, regardless of the grafting material. Histomorphometric analyses at 4 weeks demonstrated higher amount of bone formation through the defect for DBBB group. However, at 8 weeks, DBBL and DBBB demonstrated osteoconductivity and low resorption rates with evidence of statistically similar bone regeneration through the complete boney defect. Finally, DBBB presented lower soft tissue migration within the defect when compared to DBBL at both evaluation time points. DBBB and DBBL presented similar bone regeneration performance and slow resorption rates. Although both materials promoted bone regeneration through the complete defect, DBBB presented lower soft tissue migration within the defects at 4- and 8-weeks.

In Vivo Models to Evaluate Antitumor Drugs Effect on Vasculogenic Mimicry.

The vasculogenic mimicry (VM) in vivo evaluation is challenging, and new models have been proposed to evaluate antitumor effect of different compounds using in vivo models. However, there is no gold standard in vivo models established for VM evaluation. As occurs for other in vivo tumor analysis, the use of immunodeficient mouse model and cell line with in vivo tumorigenicity and ability to induce vasculogenic mimicry is the most used model.

A Retrospective Observational Cohort Study of Periprosthetic Hip Infection Treated by one-stage Method Including Cases With Bone Graft Reconstruction.

Purpose: Prosthetic joint infection (PJI) is a devastating complication that can affect hip arthroplasty. Its treatment is extremely difficult, and issues regarding the optimal treatment remain unanswered. This study intended to show the effectiveness of the one-stage treatment of PJI. Materials and Methods: A retrospective observational cohort study performed from July 2014- August 2018. All patients with suspected PJI were included. Major and minor criteria developed by the International Consensus on Periprosthetic Joint Infection (ICPJI) was used to define infection. Laboratory tests and image exams were performed, and all patients were followed for at least 2 years. Outcomes: Success rate (2018 ICPJI definition to success) in treatment of PJI using one-stage revision method. Clinical and functional outcomes defined by Harris Hip Score (HHS). Results: Thirty-one patients were screened and 18 analyzed. 69.85 ± 9.76 years was the mean age. Mean follow-up time was 63.84 ± 18.55 months. Ten patients had acetabular defects and required bone graft reconstruction. Sixteen patients were classified as Tier 1, 1 as Tier 3D, and as 1 Tier 3E. Almost 90% of patients submitted to one-stage revision with acetabulum graft reconstruction were free of infection. The overall infection survival rate was 78.31±6.34 months. Candida albicans and sinus tract were statistically significant in univariate Cox's analysis. The predictor of one-stage revision surgery failure that remained final Cox's regression model was C. albicans (hazard ratio [HR]: 4.47). Conclusion: Treatment through one-stage revision surgery associated with 6 months of antimicrobial is a viable option with acceptable results even when bone graft reconstruction is necessary. C. albicans was a strong predictor of failure in this cohort.

Hematological Changes after Caprine Demineralized Bone Matrix Implantation in Ulnar Critical Defect of Rabbit Model / Alterações hematológicas após implante de matriz óssea desmineralizada caprina em modelo de defeito ulnar crítico em coelhos

Abstract Objective Several animal models have been used in fracture healing and bone graft studies, but hematological responses are seldom reported. Therefore, the present study reported the hematological changes observed in rabbits that underwent xenografting of caprine demineralized bone matrix (CDBM). Method Twenty-four (24) male rabbits (2.5 0.5kg) were acquired for the purpose of this study and were randomly assigned to three groups: autologous bone graft (ABG), unfilled (NC), and caprine demineralized bone matrix (CDBM). Blood samples were collected through cardiac puncture under xylazine-ketamine anesthesia on day 0 (baseline), and on days 28 and 56 postsurgery and were analyzed manually within 2hours of collection. Statistical analysis was performed using a two-way analysis of variance (ANOVA) with repeated measures, and a p-value< 0.05 was considered significant. Result There was an overall significant difference in the values of total white blood cell count (p» 0.0043), neutrophil count (p< 0.0001), monocyte count (p» 0.0184), red blood cell count (p» 0.003), hemoglobin concentration (p< 0.0001) and packed cell volume (p< 0.0001) across the days and the treatment groups. There was, however, no overall significant difference in lymphocyte count (p» 0.4923), basophil count (p» 0.4183), and eosinophil count (0.4806) within days. Conclusion Response to CDBM grafting in rabbits could, therefore, be said to be characterized by marked leukocytosis with neutrophilia, lymphocytosis, and monocytosis by day 28 of postgrafting. This could form the basis with which hematology can be used to monitor body response of bone graft animal models.

Resumo Objetivo Diversos modelos animais têm sido usados em estudos sobre enxertos ósseos e o tratamento de fraturas, mas as respostas hematológicas são raramente relatadas. Este estudo descreveu as alterações hematológicas observadas em coelhos submetidos a xenoenxertos de matriz óssea desmineralizada caprina (MODC). Métodos Vinte e quatro (24) coelhos machos (2,5 0,5 kg) foram adquiridos para este estudo e divididos aleatoriamente em três grupos: enxerto ósseo autólogo (EOA); controle negativo sem preenchimento (SP) e matriz óssea desmineralizada caprina (MODC). Amostras de sangue foram coletadas por punção cardíaca sob anestesia com xilazina-quetamina no dia 0 (para estabelecimento dos valores basais) e aos dias 28 e 56 após a cirurgia; essas amostras foram submetidas à análise manual em até 2 horas após a coleta. A análise estatística foi composta por análise de variância (ANOVA) de dois fatores com medidas repetidas, e o valor de p< 0,05 foi considerado significativo. Resultados Houve uma diferença geral significativa nos números de leucócitos totais (p» 0,0043), neutrófilos (p< 0,0001), monócitos (p» 0,0184) e hemácias (p» 0,003), na concentração de hemoglobina (p< 0,0001) e no hematócrito (p< 0,0001) ao longo dos dias e entre os grupos de tratamento. No entanto, não houve diferença global significativa no número de linfócitos (p» 0,4923), basófilos (p» 0,4183) e eosinófilos (p» 0,4806) entre os dias. Conclusão A resposta ao enxerto de MODC em coelhos é, portanto, caracterizada por leucocitose intensa com neutrofilia, linfocitose e monocitose no 28° dia após o procedimento. Esses dados podem basear a utilização da hematologia no monitoramento da resposta corporal em modelos animais de enxerto ósseo.

Repair of ovine peripheral nerve injuries with xenogeneic human acellular sciatic nerves prerecellularized with allogeneic Schwann-like cells-an innovative and promising approach.

INTRODUCTION: The iatrogenic effects of repairing peripheral nerve injuries (PNIs) with autografts (AGTs) encouraged the present study to involve a new approach consisting of grafting xenogeneic prerecellularized allogeneic cells instead of AGTs. METHODS: We compared sheep's AGT regenerative and functional capacity with decellularized human nerves prerecellularized with allogeneic Schwann-like cell xenografts (onwards called xenografts). Mesenchymal stem cells were isolated from ovine adipose tissue and induced in vitro to differentiate into Schwann-like cells (SLCs). Xenografts were grafted in ovine sciatic nerves. Left sciatic nerves (20 mm) were excised from 10 sheep. Then, five sheep were grafted with 20 mm xenografts, and five were reimplanted with their nerve segment rotated 180° (AGT). RESULTS: All sheep treated with xenografts or AGT progressively recovered the strength, movement, and coordination of their intervened limb, which was still partial when the study was finished at sixth month postsurgery. At this time, numerous intrafascicular axons were observed in the distal and proximal graft extremes of both xenografts or AGTs, and submaximal nerve electrical conduction was observed. The xenografts and AGT-affected muscles appeared partially stunted. CONCLUSIONS: Xenografts and AGT were equally efficacious in starting PNI repair and justified further studies using longer observation times. The hallmarks from this study are that human xenogeneic acellular scaffolds were recellularized with allogenic SCL and were not rejected by the nonhuman receptors but were also as functional as AGT within a relatively short time postsurgery. Thus, this innovative approach promises to be more practical and accessible than AGT or allogenic allografts and safer than AGT for PNI repair.

Antitumor effect of isoquercetin on tissue vasohibin expression and colon cancer vasculature.

Tumor cells trigger angiogenesis through the expression of angiogenic factors. Vasohibins (VASHs) are a family of peptides that regulate angiogenesis. Flavonoids have antiproliferative antitumor properties; however, few studies have highlighted their antiangiogenic potential. This study evaluated the flavonoid isoquercetin (Q3G) as an antitumor compound related to colon cancer vascularization and regulation of VASH1 and 2. Mice bearing xenogeneic colon cancer (n = 15) were divided into 3 groups: Q3G-treated (gavage, daily over a week), bevacizumab-treated (intraperitoneal, single dose), or untreated animals. Tumor growth, histological characteristics, blood vessel volume, and VASH1 and 2 expressions were analyzed. Q3G impaired tumor growth and vascularization, upregulated VASH1, and downregulated VASH2 in comparison to untreated animals. Mice treated with Q3G showed approximately 65% fewer blood vessels than untreated animals and 50% fewer blood vessels than mice treated with bevacizumab. Thus, we show that Q3G has antitumor activity, impairs vascularization, and differentially modulates VASH1 and 2 expressions in colon cancer.

Angiogenesis in patient-derived xenografts of odontogenic myxoma.

Previously, by employing 3D organotypic tissue culture and patient-derived xenograft (PDX) model, oral myxoma response to a MAPK/MEK inhibitor was observed. Gross examination of the tumour fragments obtained after 55 days of PDX grafting revealed increased capsule vascularization. Microscopic analyses showed blood capillaries intermixed with myxoma cells, but the origin of these capillaries, from mice or humans, was not established. This study aimed to investigate whether the endothelial cells observed in the myxoma PDX model are derived from the mouse or from the primary human tumour. Immunohistochemistry was performed on five tumour fragments from the PDX of myxoma after 55 days of implantation in mice. Immunopositivity for antibodies against human (HLA-ABC) and mouse (H2 Db/H2-D1) major histocompatibility complex class I (MHCI) was assessed in the endothelial cells. The endothelial cells in the PDX fragments revealed a membrane staining for the human MHCI protein in the PDX tumour and adjacent connective tissue capsule, indicating that capillaries were derived from the human tumour fragment. Considering the probable human origin of the endothelial cells from capillary blood vessels in the myxoma PDX, we conclude that this PDX model is an interesting model to study myxoma angiogenesis.

Biological Behavior of Xenogenic Scaffolds in Alcohol-Induced Rats: Histomorphometric and Picrosirius Red Staining Analysis.

In this experimental protocol, the objective was to evaluate the biological behavior of two xenogenic scaffolds in alcohol-induced rats through histomorphometric and Picrosirius Red staining analysis of non-critical defects in the tibia of rats submitted or not to alcohol ingestion at 25% v/v. Eighty male rats were randomly divided into four groups (n = 20 each): CG/B (water diet + Bio-Oss® graft, Geistlich Pharma AG, Wolhusen, Switzerland), CG/O (water diet + OrthoGen® graft, Baumer, Mogi Mirim, Brazil), AG/B (25% v/v alcohol diet + Bio-Oss® graft), and AG/O (25% v/v alcohol diet + OrthoGen® graft). After 90 days of liquid diet, the rats were surgically obtained, with a defect in the tibia proximal epiphysis; filled in according to their respective groups; and euthanized at 10, 20, 40 and 60 days. In two initial periods (10 and 20 days), all groups presented biomaterial particles surrounded by disorganized collagen fibrils. Alcoholic animals (AG/B and AG/O) presented, in the cortical and medullary regions, a reactive tissue with inflammatory infiltrate. In 60 days, in the superficial area of the surgical cavities, particles of biomaterials were observed in all groups, with new compact bone tissue around them, without complete closure of the lesion, except in non-alcoholic animals treated with Bio-Oss® xenograft (CG/B), where the new cortical interconnected the edges of the defect. Birefringence transition was observed in the histochemical analysis of collagen fibers by Picrosirius Red, in which all groups in periods of 10 and 20 days showed red-orange birefringence, and from 40 days onwards greenish-yellow birefringence, which demonstrates the characteristic transition from the formation of thin and disorganized collagen fibers initially to more organized and thicker later. In histomorphometric analysis, at 60 days, CG/B had the highest volume density of new bone (32.9 ± 1.15) and AG/O the lowest volume density of new bone (15.32 ± 1.71). It can be concluded that the bone neoformation occurred in the defects that received the two biomaterials, in all periods, but the Bio-Oss® was superior in the results, with its groups CG/B and AG/B displaying greater bone formation (32.9 ± 1.15 and 22.74 ± 1.15, respectively) compared to the OrthoGen® CG/O and AG/O groups (20.66 ± 2.12 and 15.32 ± 1.71, respectively), and that the alcoholic diet interfered negatively in the repair process and in the percentage of new bone formed.

Central giant cell granulomas of the jaws stromal cells harbour mutations and have osteogenic differentiation capacity, in vivo and in vitro.

BACKGROUND: Central giant cell granulomas (CGCG) of the jaws are osteolytic lesions that may behave aggressively and respond poorly to surgery. Microscopically, in addition to giant cells, there is a mononuclear cell population composed of macrophage/monocytic cells and spindle-shaped cells of mesenchymal origin. Seventy two percent of these tumours harbour mutually exclusive TRPV4, KRAS and FGFR1 mutations. We aimed to assess the mutational status of mononuclear and giant cells and the osteogenic potential of stromal cells in vitro and in vivo. METHODS AND RESULTS: We screened CGCG for signature mutations and used laser-capture microdissection to demonstrate that the mutations are restricted to the mononuclear cells. Additionally, we established CGCG primary cell culture and observed that the cells retained the mutations throughout passages. By flow cytometry, we observed predominance of CD14- CD51- CD61- cells, consistent with the expected profile for stromal cells. Considering the mesenchymal origin of stromal cells, we assessed the osteogenic differentiation potential of CGCG cells in culture by cytochemistry (von Kossa and alizarin red staining), alkaline phosphatase (ALP) activity assay and gene expression of osteogenic markers. CGCG cells presented self-capacity to increase ALP levels in a time-dependent manner and under osteogenic induction presented increasing number of calcium deposits, and overall higher expression of osteocalcin, RUNX2, ALPL and osteopontin than cells without osteogenic induction. A patient-derived xenograft model for CGCG was established, and osteoid material deposition was observed. CONCLUSION: Collectively, the results confirm that the signature mutations are restricted to stromal cells in CGCG, and the in vitro and in vivo results support that these cells have the capacity to differentiate into osteoblasts, in line with the bone formation often observed in the stroma of these lesions.

In-depth characterization of a new patient-derived xenograft model for metaplastic breast carcinoma to identify viable biologic targets and patterns of matrix evolution within rare tumor types.

Metaplastic breast carcinoma (MBC) is a rare breast cancer subtype with rapid growth, high rates of metastasis, recurrence and drug resistance, and diverse molecular and histological heterogeneity. Patient-derived xenografts (PDXs) provide a translational tool and physiologically relevant system to evaluate tumor biology of rare subtypes. Here, we provide an in-depth comprehensive characterization of a new PDX model for MBC, TU-BcX-4IC. TU-BcX-4IC is a clinically aggressive tumor exhibiting rapid growth in vivo, spontaneous metastases, and elevated levels of cell-free DNA and circulating tumor cell DNA. Relative chemosensitivity of primary cells derived from TU-BcX-4IC was performed using the National Cancer Institute (NCI) oncology drug set, crystal violet staining, and cytotoxic live/dead immunofluorescence stains in adherent and organoid culture conditions. We employed novel spheroid/organoid incubation methods (Pu·MA system) to demonstrate that TU-BcX-4IC is resistant to paclitaxel. An innovative physiologically relevant system using human adipose tissue was used to evaluate presence of cancer stem cell-like populations ex vivo. Tissue decellularization, cryogenic-scanning electron microscopy imaging and rheometry revealed consistent matrix architecture and stiffness were consistent despite serial transplantation. Matrix-associated gene pathways were essentially unchanged with serial passages, as determined by qPCR and RNA sequencing, suggesting utility of decellularized PDXs for in vitro screens. We determined type V collagen to be present throughout all serial passage of TU-BcX-4IC tumor, suggesting it is required for tumor maintenance and is a potential viable target for MBC. In this study we introduce an innovative and translational model system to study cell-matrix interactions in rare cancer types using higher passage PDX tissue.

A novel second-generation platinum derivative and evaluation of its anti-cancer potential

Abstract Cisplatin is the primary anti-cancer agent for the treatment of most solid tumors. However, platinum-based anti-cancer chemotherapy produces severe side effects due to its poor specificity. There are a broad interest and literature base for a novel mechanism of action on platinum derivatives. Additionally, combining cisplatin with histone deacetylase inhibitors (HDACi) such as 4-hydroxybenzoic acid derivatives showed promising results in treating solid tumors. Here we aimed to conjugate 4-hydroxybenzoic acid with platinum to obtain a novel platinum derivative that can overcome cisplatin resistance. Cis-4-hydroxyphenylplatinum(II)diamine compound was synthesized under mild conditions and characterized. Cytotoxicity assay was performed on SKOV3-Luc and A549-Luc cells. Hemocompatibility and serum protein binding analysis were performed. Treatment potential was evaluated in xenograft tumor models. Biodistribution was tested on tumor-bearing mice via Pt analysis in organs with ICP-MS, ex vivo. In this study, cis-4-hydroxyphenylplatinum (II) diamine was synthesized with a yield of 62%. The MTT assay on A549-Luc and SKOV3-Luc cell lines resulted in IC50 values of 17.82 and 7.81 µM, respectively. While tumor growth was continued in the control group, the tumor volume decreased in the treatment group. All results point to the conclusion that the new compound has the potential to treat solid tumors

Opuntia ficus-indica Extract and Isorhamnetin-3-O-Glucosyl-Rhamnoside Diminish Tumor Growth of Colon Cancer Cells Xenografted in Immune-Suppressed Mice through the Activation of Apoptosis Intrinsic Pathway.

This study aimed to evaluate the effects of Opuntia ficus-indica extract (OFI-E) and its glycoside isorhamnetin-3-O-glucosyl-rhamnoside (IGR) on the growth of human colorectal adenocarcinoma cells and in a xenografted-immunosuppressed mice model. The IC50 values of OFI-E and IGR on colon cancer cells (HT-29 RFP) were determinate, as well as their effects on the cell cycle and apoptosis induction. OFI-E and IGR produced an increased in apoptosis induction, ROS production and a G0/G1 cell cycle arrest. In xenografted-inmunosupressed mice, OFI-E and IGR reduced the tumor growth rate, myeloperoxidase activity and total cholesterol levels. OFI-E and IGR reduced the tumor growth through the overexpression of cleaved Caspase-9, Hdac11, and Bai1 proteins. OFI-E reduced the expression of bcl-2. Results demonstrated the chemopreventive effects of OFI-E, and its purified compound IGR, showing their potential as an alternative in the treatment of colorectal cancer.

Histomorphometric, Immunohistochemical and Microtomographic Comparison between Autogenous and Xenogenous Bone Blocks for Mandibular Lateral Augmentation in Rabbits.

BACKGROUND: The volumetric and biological behaviors of equine block grafts compared with autogenous block grafts have not yet been assessed. Hence, the aim of the present study was to compare-by means of histomorphometry, immunohistochemistry and microtomography-the graft incorporation and remodeling processes of autogenous and equine xenogenous bone blocks used for mandibular lateral augmentation in rabbits. METHODS: Autogenous bone grafts harvested from the iliac bony crest and equine block grafts were secured to the lateral aspect of the mandible angle of eighteen rabbits. The healing after 7, 20 and 60 days was assessed in six animals each period. RESULTS: After 60 days, new bone was present 24.2 ± 11.2% and 31.6 ± 13.3% in the autograft and xenograft groups, respectively. A better integration to the recipient sites was observed in the autogenous compared with the xenogenous blocks. CONCLUSIONS: Both xenogenous and autogenous bone blocks presented similar percentages of newly formed bone over time. However, bone volume, the quality of the grafted area and graft incorporation to the recipient sites were superior in the autogenous compared with the equine xenogenous graft sites.

[6]-Gingerol-Derived Semi-Synthetic Compound SSi6 Inhibits Tumor Growth and Metastatic Dissemination in Triple-Negative Breast Cancer Xenograft Models.

Breast cancer metastasis is the most common cause of cancer death in women worldwide. Triple-negative breast cancers (TNBC) form a heterogeneous group of tumors that have higher relapse rates and poorer survival compared to other breast cancer subtypes. Thus, this work reports the antitumor and antimetastatic activities of a [6]-gingerol-derived semi-synthetic compound named SSi6 on MDA-MB-231 TNBC cells using xenograft models. SSi6 did not cause toxic effects in vivo as demonstrated by body weight and hematological and histological evaluations. From the orthotopic xenograft model, we demonstrated that SSi6 slows and inhibits the growth of the primary tumor, as well as prevents metastatic spontaneous progression from lymph nodes to the lungs. Moreover, a second xenograft model with resection of the primary tumor showed that SSi6 also blocks the progression of metastases from the lymph nodes to other visceral organs. Taken together, our results demonstrate that SSi6 is a promising compound to be investigated in other preclinical and clinical models to be applied as a complementary therapy for TNBC.