High VEGF with rapid growth and early metastasis in a mouse osteosarcoma model

Correlation of High-Grade Osteosarcoma Response to Chemotherapy with Enhanced Tissue Immunological Response: Analysis of CD95R, IFN-γ, Catalase, Hsp70, and VEGF

High-grade osteosarcoma, a primary malignant bone tumour, is experiencing a global increase in reported incidence with varied prevalence. Despite advances in management, which include surgery and neoadjuvant chemotherapy often an unsatisfactory outcome is found due to poor or heterogeneous response to chemotherapy. Our study delved into chemotherapy responses in osteosarcoma patients and associated molecular expressions, focusing on CD95 receptor (CD95R), interferon (IFN)-γ, catalase, heat-shock protein (Hsp)70, and vascular endothelial growth factor (VEGF). Employing immunohistochemistry and Huvos grading of post-chemo specimens, we analysed formalin-fixed paraffin-embedded (FFPE) osteosarcoma tissue of resected post-chemotherapy specimens from Dr. Soetomo General Academic Hospital in Surabaya, Indonesia (DSGAH), spanning from 2016 to 2020. Results revealed varied responses (poor 40.38%, moderate 48.08%, good 11.54%) and distinct patterns in CD95R, IFN-γ, catalase, Hsp70, and VEGF expression. Significant differences among response groups were observed in CD95R and IFN-γ expression in tumour-infiltrating lymphocytes. The trend of diminishing CD95R expression from poor to good responses, accompanied by an increase in IFN-γ, implied a reduction in the count of viable osteosarcoma cells with the progression of Huvos grading. Catalase expression in osteosarcoma cells was consistently elevated in the poor response group, while Hsp70 expression was highest. VEGF expression in macrophages was significantly higher in the good response group. In conclusion, this study enhances our understanding of immune-chemotherapy interactions in osteosarcoma and identifies potential biomarkers for targeted interventions.

Promise and Challenges of T Cell Immunotherapy for Osteosarcoma

The cure rate for metastatic or relapsed osteosarcoma has not substantially improved over the past decades despite the exploitation of multimodal treatment approaches, allowing long-term survival in less than 30% of cases. Patients with osteosarcoma often develop resistance to chemotherapeutic agents, where personalized targeted therapies should offer new hope. T cell immunotherapy as a complementary or alternative treatment modality is advancing rapidly in general, but its potential against osteosarcoma remains largely unexplored. Strategies incorporating immune checkpoint inhibitors (ICIs), chimeric antigen receptor (CAR) modified T cells, and T cell engaging bispecific antibodies (BsAbs) are being explored to tackle relapsed or refractory osteosarcoma. However, osteosarcoma is an inherently heterogeneous tumor, both at the intra- and inter-tumor level, with no identical driver mutations. It has a pro-tumoral microenvironment, where bone cells, stromal cells, neovasculature, suppressive immune cells, and a mineralized extracellular matrix (ECM) combine to derail T cell infiltration and its anti-tumor function. To realize the potential of T cell immunotherapy in osteosarcoma, an integrated approach targeting this complex ecosystem needs smart planning and execution. Herein, we review the current status of T cell immunotherapies for osteosarcoma, summarize the challenges encountered, and explore combination strategies to overcome these hurdles, with the ultimate goal of curing osteosarcoma with less acute and long-term side effects.

Cracking the code: Deciphering the role of the tumor microenvironment in osteosarcoma metastasis

Osteosarcoma (OS) is the most common malignant bone tumor in children and adolescents. It is characterized by a rapid progression, poor prognosis, and early pulmonary metastasis. Over the past 30 years, approximately 85% of patients with osteosarcoma have experienced metastasis. The five-year survival of patients with lung metastasis during the early stages of treatment is less than 20%. The tumor microenvironment (TME) not only provides conditions for tumor cell growth but also releases a variety of substances that can promote the metastasis of tumor cells to other tissues and organs. Currently, there is limited research on the role of the TME in osteosarcoma metastasis. Therefore, to explore methods for regulating osteosarcoma metastasis, further investigations must be conducted from the perspective of the TME. This will help to identify new potential biomarkers for predicting osteosarcoma metastasis and assist in the discovery of new drugs that target regulatory mechanisms for clinical diagnosis and treatment. This paper reviews the research progress on the mechanism of osteosarcoma metastasis based on TME theory, which will provide guidance for the clinical treatment of osteosarcoma.

DEPDC1 as a crucial factor in the progression of human osteosarcoma

OBJECTIVE

Novel therapeutic strategies are emerging with the increased understanding of the underlying mechanisms of human osteosarcoma. This current study tends to decipher the potentially critical role of DEP domain-containing 1 (DEPDC1), a tumor-related gene, during the progression of osteosarcoma.

METHODS

Bioinformatics analysis of 25,035 genes from the National Center for Biotechnology Information (NCBI) databases was performed to screen differentially expressed genes between osteosarcoma and normal control groups, complemented by the examination of 85 clinical osteosarcoma specimens. Furthermore, the manipulation of DEPDC1 expression levels by using silencing RNA (siRNA) or lentiviral vector intervention on human osteosarcoma cells was performed to reveal its role and interactions in in vitro and in vivo settings.

RESULTS

Gene expression profile analysis and immunohistochemical (IHC) examination suggested that DEPDC1 is highly expressed in human osteosarcoma cells and tumor tissue. The silencing of DEPDC1 arrested osteosarcoma cell proliferation, promoted apoptosis, and ceased tumor metastasis. Studies involving clinical human osteosarcoma cases exhibited a strong correlation of DEPDC1 over-expressed osteosarcoma specimens with a reduced patient survival rate.

CONCLUSIONS

Collectively, this study demonstrated that DEPDC1 is a critical driver in the promotion of osteosarcoma progression and results in poor patient prognosis. Genetically targeting or pharmacologically inhibiting DEPDC1 may serve as a promising strategy for treating human osteosarcoma.

Current research progress in targeted anti-angiogenesis therapy for osteosarcoma

Osteosarcoma (OS) is the most common primary malignant bone tumour with a peak in incidence during adolescence. Delayed patient presentation and diagnosis is common with approximately 15% of OS patients presenting with metastatic disease at initial diagnosis. With the introduction of neoadjuvant chemotherapy in the 1970s, disease prognosis improved from 17% to 60%-70% 5-year survival, but outcomes have not significantly improved since then. Novel and innovative therapeutic strategies are urgently needed as an adjunct to conventional treatment modalities to improve outcomes for OS patients. Angiogenesis is crucial for tumour growth, metastasis and invasion, and its prevention will ultimately inhibit tumour growth and metastasis. Dysregulation of angiogenesis in bone microenvironment involving osteoblasts and osteoclasts might contribute to OS development. This review summarizes existing knowledge regarding pre-clinical and developmental research of targeted anti-angiogenic therapy for OS with the aim of highlighting the limitations associated with this application. Targeted anti-angiogenic therapies include monoclonal antibody to VEGF (bevacizumab), tyrosine kinase inhibitors (Sorafenib, Apatinib, Pazopanib and Regorafenib) and human recombinant endostatin (Endostar). However, considering the safety and efficacy of these targeted anti-angiogenesis therapies in clinical trials cannot be guaranteed at this point, further research is needed to completely understand and characterize targeted anti-angiogenesis therapy in OS.

A Novel Orthotopic Implantation Technique for Osteosarcoma Produces Spontaneous Metastases and Illustrates Dose-Dependent Efficacy of B7-H3-CAR T Cells

The outcome for metastatic pediatric osteosarcoma (OS) remains poor. Thus, there is an urgent need to develop novel therapies, and immunotherapy with CAR T cells has the potential to meet this challenge. However, there is a lack of preclinical models that mimic salient features of human disease including reliable development of metastatic disease post orthotopic OS cell injection. To overcome this roadblock, and also enable real-time imaging of metastatic disease, we took advantage of LM7 OS cells expressing firefly luciferase (LM7.ffLuc). LM7.ffLuc were implanted in a collagen mesh into the tibia of mice, and mice reliably developed orthotopic tumors and lung metastases as judged by bioluminescence imaging and histopathological analysis. Intratibial implantation also enabled surgical removal by lower leg amputation and monitoring for metastases development post-surgery. We then used this model to evaluate the antitumor activity of CAR T cells targeting B7-H3, an antigen that is expressed in a broad range of solid tumors including OS. B7-H3-CAR T cells had potent antitumor activity in a dose-dependent manner and inhibited the development of pulmonary metastases resulting in a significant survival advantage. In contrast T cells expressing an inactive B7-H3-CAR had no antitumor activity. Using unmodified LM7 cells also enabled us to demonstrate that B7-H3-CAR T cells traffic to orthotopic tumor sites. Hence, we have developed an orthotopic, spontaneously metastasizing OS model. This model may improve our ability not only to predict the safety and efficacy of current and next generation CAR T cell therapies but also other treatment modalities for metastatic OS.

Determination of VEGF165 using impedimetric aptasensor based on cyclohexanehexone-melem covalent-organic framework

A porous nanostructured covalent-organic framework (COF) has been prepared via condensation polymerization between the two building blocks of melem and hexaketocyclohexane octahydrate (represented as M-HO-COF). Basic characterizations revealed that the M-HO-COF network was composed of C=N and highly conjugated aromatic moieties, along with a high surface area, large pore size, remarkable electrochemical activity, and strong bioaffinity toward aptamer strands. Given that the vascular endothelial growth factor 165 (VEGF₁₆₅)-targeted aptamer was stably anchored over M-HO-COF via weak intermolecular forces, the prepared M-HO-COF network exhibited great potential as a sensitive and selective platform for the impedimetric VEGF₁₆₅ aptasensor. Consequently, the M-HO-COF-based aptasensor displayed an ultralow limit of detection of 0.18 fg mL^-1 within a wide range of VEGF₁₆₅ concentrations from 1 fg mL^-1 to 10 ng mL^-1. Considering its strong fluorescence performance, excellent biocompatibility, and small nanosheet-like structure, the obtained COF-based aptasensor showed a superior sensing performance and regeneration capability after 7 regeneration cycles for the detection of osteosarcoma cells (K7M2 cells), which overexpressed with VEGF₁₆₅, with a low limit of detection of 49 cells mL^-1. For real f human serum samples, the obtained COF-based aptasensor exhibits acceptable mean apparent recoveries of 97.41% with a relative standard deviation of 4.60%. Furthermore, the proposed bifunctional aptasensor for the detection VEGF₁₆₅ and K7M2 cells exhibited good stability, appropriate selectivity toward other biomarkers or normal cells, acceptable reproducibility, and applicability. A bifunctional sensing system was constructed for detecting osteosarcoma cells (K7M2 cells) and VEGF₁₆₅ based on the a porous nanostructured covalent-organic framework (M-HO-COF) via condensation polymerization between melem and hexaketocyclohexane octahydrate. The M-HO-COF-based aptasensor displayed ultralow detection limit of 0.18 fg mL^-1 toward VEGF₁₆₅ and 49 cell mL^-1 for K7M2 cells with high selectivity, acceptable reproducibility, and good stability.

Combination of anginex gene therapy and radiation decelerates the growth and pulmonary metastasis of human osteosarcoma xenografts

Investigate whether rAAV-anginex gene therapy combined with radiotherapy could decrease growth and pulmonary metastasis of osteosarcoma in mice and examine the mechanisms involved in this therapeutic strategy. During in vitro experiment, multiple treatment regimes (rAAV-eGFP, radiotherapy, rAAV-anginex, combination therapy) were applied to determine effects on proliferation of endothelial cells (ECs) and G-292 osteosarcoma cells. During in vivo analysis, the same multiple treatment regimes were applied to osteosarcoma tumor-bearing mice. Use microcomputed tomography to evaluate tumor size. Eight weeks after tumor cell inoculation, immunohistochemistry was used to assess the therapeutic efficacy according to microvessel density (MVD), proliferating cell nuclear antigen (PCNA), and terminal-deoxynucleotidyl transferase-mediated nick-end labeling (TUNEL) assays. Metastasis of lungs was also evaluated by measuring number of metastatic nodules and wet weight of metastases. The proliferation of ECs and the tumor volumes in combination therapy group were inhibited more effectively than the other three groups at end point (P < 0.05). Cell clone assay showed anginex had radiosensitization effect on ECs. Immunohistochemistry showed tumors from mice treated with combination therapy exhibited the lowest MVD and proliferation rate, with highest apoptosis rate, as confirmed by IHC staining for CD34 and PCNA and TUNEL assays (P < 0.05). Combination therapy also induced the fewest metastatic nodules and lowest wet weights of the lungs (P < 0.05). rAAV-anginex combined with radiotherapy induced apoptosis of osteosarcoma cells and inhibited tumor growth and pulmonary metastasis on the experimental osteosarcoma models. We conclude that the primary mechanism of this process may be due to sensitizing effect of anginex to radiotherapy.

Celecoxib attenuates cachectic events in mice by modulating the expression of vascular endothelial growth factor

Chronic inflammation is one of the main symptoms of cancer cachexia, and cyclooxygenase 2 inhibitors, such as celecoxib, may be beneficial in counteracting the major symptoms of this syndrome. In the current study, celecoxib was orally administered to BALB/c male mice with colon 26 adenocarcinoma. Tumor growth, survival rate, body weight and food intake of the mice with cancer cachexia were recorded during the experiments. The host inflammatory response was assessed by morphological observations and hematoxylin-eosin staining. The serum levels of vascular endothelial growth factor (VEGF), granulocyte-macrophage colony-stimulating factor, interleukin-6 and tumor necrosis factor-α in mice with cancer cachexia were measured by ELISA. Celecoxib administration attenuated the decline in body weight and food intake of mice with cancer cachexia, and improved the survival rate of cachectic mice. Erythrocyte counts and hemoglobin concentration significantly increased in cachectic mice receiving celecoxib compared with control cachectic mice. Notably, celecoxib administration significantly reduced the serum level of VEGF in mice with colon 26 adenocarcinoma, and the cachectic events were also relieved by treatment with a VEGF antibody. The cyclooxygenase 2 inhibitor celecoxib produced positive therapeutic effects in mice with cancer cachexia. This function was regulated at least partly by downregulation of serum levels of VEGF.

HIF-1 alpha overexpression correlates with poor overall survival and disease-free survival in gastric cancer patients post-gastrectomy

Background

Overall, gastric cancer prognosis remains poor. Detailed characterization of molecular markers that govern gastric cancer pathogenesis is warranted to establish innovative therapeutic options. HIF-1α overexpression has been linked to poor gastric cancer prognosis. However, though researched for years, the prognostic role of HIF-1α in gastric cancer is still controversial. Hence, the objective of the present study was to analyze the prognostic values of HIF-1α, TGF-β, VEGF and pERK1/2 in gastric cancer patients following gastrectomy.

Methods

This study included 446 patients with confirmed gastric cancer who underwent gastrectomy in a single Chinese Cancer Center between 2005 and 2006. Clinicopathologic features, as well as immunohistochemical analysis of TGF-β, HIF-1α, VEGF and pERK1/2 were determined. Long-term survival of these patients was analyzed using univariate and multivariate analyses.

Results

HIF-1α overexpression was more frequent in patients with hepatic metastases (71.6% versus 43.0% in those without hepatic metastases, P = 0.000, χ² = 23.086) and more frequent in patients with peritoneum cavity metastasis (62.3% versus 43.0% in those without such metastasis, P = 0.000, χ² = 13.691). In univariate analysis, patients with HIF-1α overexpression had a shorter disease-free survival (DFS) and overall survival (OS) than patients with weak-expression (DFS: NA VS. 16.8 m, P = 0.000, χ² = 74.937; OS: NA VS. 25.5 m, P = 0.000, χ² = 90.594). Importantly, HIF-1α overexpression was a promising prognostic marker for poor survival by multivariate analysis (DFS: HR 2.766, 95%CI 2.136–2.583, P = 0.000; OS: HR 3.529, 95%CI 2.663–4.667, P = 0.000).

Conclusions

HIF-1α overexpression could be considered a useful independent prognostic biomarker in gastric cancer after gastrectomy, and is correlated to both a poor overall survival and disease-free survival in these patients. HIF-1α expression can be used to stratify patients at higher risk for poor prognosis, and is potentially an important therapeutic target in gastric cancer patients.

Expression of Vascular Endothelial Growth Factor correlates with the advance of clinical osteosarcoma

PURPOSE

Osteosarcoma is the most common primary malignancy in orthopaedic surgery. Studies suggest that expression of VEGF and high vascularity within osteosarcoma may correlate with poor prognosis. The purpose of this study was to determine whether there was a correlation of VEGF expression with clinical tumour stage and metastasis.

METHODS

This retrospective case series examined 54 cases of osteosarcoma patients who were treated during a ten-year period. Relevant clinical information included age, gender, tumour location, stage, adjuvant therapy, morbidity, mortality, and tumour subtypes. The clinical information was analysed for correlation of VEGF expression and tumour prognosis. Tumour sections were examined by routine H&E and by immunohistochemistry for VEGF, CD31, and the oncogenes c-myc and c-fos.

RESULTS

There was a significantly positive correlation between VEGF expression and tumour stages among these cases (p < 0.01). The data also suggested a higher cancer recurrence and more frequent cases of remote metastasis in the high-VEGF group compared to the low-VEGF group. VEGF expression also positively associated with c-fos and c-myc expressions in the primary tumour sections.

CONCLUSION

The results of this study highlight the role of VEGF in angiogenesis and tumour burden. Data also suggest the influence of VEGF may associate with the elevations of c-fos and c-myc expression. The development of novel therapies to target the VEGF pathway in osteosarcoma may lead to improved survival.

The role of osteoclasts and tumour-associated macrophages in osteosarcoma metastasis

Osteosarcoma (OS) is the most common primary bone tumour in the paediatric age group. Treatment-refractory pulmonary metastasis continues to be the major complication of OS, reducing the 5-year survival rate for these patients to 10-20%. The mechanisms underlying the metastatic process in OS are still unclear, but undoubtedly, a greater understanding of the factors and interactions involved in its regulation will open new and much needed opportunities for therapeutic intervention. Recent published data have identified a new role for bone-specific macrophages (osteoclasts) and tumour-associated macrophages (TAMs), in OS metastasis. In this review we discuss the contribution of TAMs and osteoclasts in the establishment and maintenance of secondary metastatic lesions, and their novel role in the prevention of metastatic disease in a primary bone cancer such as osteosarcoma.

Relationships between levels of CXCR4 and VEGF and blood-borne metastasis and survival in patients with osteosarcoma

The present study was designed to determine whether the expression of chemokine receptor CXCR4 and vascular endothelial growth factor (VEGF) is correlated with the extent of metastasis and the survival of patients with osteosarcoma. Using tissue microarrays, we analyzed the expression of CXCR4 and VEGF in tumor tissues collected from 56 patients with osteosarcoma. A two-year follow-up was performed to evaluate tumor metastatic behavior and the overall survival of the patients. There was a significant correlation between the expression of CXCR4 and the expression of VEGF in tumor tissues of these patients (P = 0.002). Univariate analysis revealed that expression of these proteins was correlated with clinical stage, but not age, gender, or serum alkaline phosphatase levels. The patients with tumors expressing CXCR4 and VEGF had worse overall survival rates compared with the patients with tumors that did not express CXCR4 (P = 0.03) or VEGF (P = 0.04). These data indicate that CXCR4 and VEGF expression is highly correlated with metastatic progression in patients with osteosarcoma and had predictive value for the metastasis and survival of osteosarcoma patients.

Effect of troglitazone on tumor growth and pulmonary metastasis development of the mouse osteosarcoma cell line LM8

Background

Osteosarcoma often develops micrometastases in the lung prior to diagnosis, causing a fatal outcome. Therefore, the prevention of pulmonary metastases is critical for the improvement of the prognosis of patients with osteosarcoma. The purpose of this study was to investigate whether troglitazone (TGZ) is considered as possible therapeutics in the treatment of growth and metastasis of osteosarcoma.

Methods

LM8 cells were treated for 3 days with various concentrations of TGZ. The effect of TGZ on cell proliferation was determined by DNA measurement in the cultures and 5-bromo-2'-deoxyuridine incorporation study. The assay of cell invasion and motility was performed using either the Matrigel-coated cell culture inserts or the uncoated cell culture inserts in the invasion chambers. The effect of TGZ on Akt signaling was assessed by Western blot analysis of Akt and p-Akt. The effects of oral administration of either TGZ (TGZ group) or ethanol (control group) on the growth of primary tumor and the development of pulmonary metastasis were examined in nude mice implanted with LM8 cells on their backs. The expression and activity of matrix metalloproteinase 2 (MMP-2) within the tumor were determined by immunohistochemistry and zymography. The microvessel density (MVD) within the tumor was determined by immunohistochemistry for CD34.

Results

TGZ dose-dependently inhibits cell proliferation. TGZ-treated cells were less invasive and less motile than untreated cells. The activity of MMP-2 secreted by TGZ-treated cells was lower than that secreted by untreated cells. TGZ decreased the level of p-Akt. The primary tumor mass was smaller in the TGZ group than in the control group. The TGZ group had less metastatic tumors in the lung compared with the control group. The expression and activity of MMP-2 within the tumor of the TGZ group were lower than those of the control group. The MVD within the tumor of the TGZ group was lower than that of the control group.

Conclusions

Inhibition of Akt signaling by TGZ may decrease the secretion of MMP-2, resulting in the decrease of invasiveness and motility in LM8 cells. Treatment of tumor-bearing mice with TGZ decreases the expression and activity of MMP-2 within the tumor, and inhibits primary tumor growth and pulmonary metastasis development. TGZ may offer a new approach in chemotherapy for osteosarcoma.

Sorafenib blocks tumour growth, angiogenesis and metastatic potential in preclinical models of osteosarcoma through a mechanism potentially involving the inhibition of ERK1/2, MCL-1 and ezrin pathways

BACKGROUND

Osteosarcoma (OS) is the most common primary bone tumour in children and young adults. Despite improved prognosis, metastatic or relapsed OS remains largely incurable and no significant improvement has been observed in the last 20 years. Therefore, the search for alternative agents in OS is mandatory.

RESULTS

We investigated phospho-ERK 1/2, MCL-1, and phospho-Ezrin/Radixin/Moesin (P-ERM) as potential therapeutic targets in OS. Activation of these pathways was shown by immunohistochemistry in about 70% of cases and in all OS cell lines analyzed. Mutational analysis revealed no activating mutations in KRAS whereas BRAF gene was found to be mutated in 4/30 OS samples from patients. Based on these results we tested the multi-kinase inhibitor sorafenib (BAY 43-9006) in preclinical models of OS. Sorafenib inhibited OS cell line proliferation, induced apoptosis and downregulated P-ERK1/2, MCL-1, and P-ERM in a dose-dependent manner. The dephosphorylation of ERM was not due to ERK inhibition. The downregulation of MCL-1 led to an increase in apoptosis in OS cell lines. In chick embryo chorioallantoic membranes, OS supernatants induced angiogenesis, which was blocked by sorafenib and it was also shown that sorafenib reduced VEGF and MMP2 production. In addition, sorafenib treatment dramatically reduced tumour volume of OS xenografts and lung metastasis in SCID mice.

CONCLUSION

In conclusion, ERK1/2, MCL-1 and ERM pathways are shown to be active in OS. Sorafenib is able to inhibit their signal transduction, both in vitro and in vivo, displaying anti-tumoural activity, anti-angiogenic effects, and reducing metastatic colony formation in lungs. These data support the testing of sorafenib as a potential therapeutic option in metastatic or relapsed OS patients unresponsive to standard treatments.

Ketoprofen in topical formulation decreases the matrix metalloproteinase-2 expression and pulmonary metastatic incidence in nude mice with osteosarcoma

The aim of this study was to investigate whether ketoprofen (KP) in topical formulation affected the tumor growth and pulmonary metastasis of LM8 cells, which were inoculated subcutaneously into the back space of male nude mice. At 7 days after inoculation, the tumor was treated topically for 3 weeks with either a KP-containing patch (KP group) or a placebo-containing patch (placebo group). The pulmonary metastatic incidence was 100% in the placebo group and 60% in the KP group. The tumor mass of the KP group without pulmonary metastasis, termed the KP/metastasis(-) group, was smaller than that of the placebo group. Immunohistochemical staining for proliferating cell nuclear antigen (PCNA), terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL), matrix metalloproteinase-2 (MMP-2), and vascular endothelial growth factor (VEGF) was performed. The tumors of the KP/metastasis(-) group contained fewer PCNA-positive cells and many more TUNEL-positive cells in comparison to the placebo group. In the placebo group, MMP-2 and VEGF were extensively expressed within the tumor, whereas in the KP/metastasis(-) group the expression of these two proteins was very low. In conclusion, the topical treatment of osteosarcoma with KP decreased the expression of MMP-2 and VEGF, thus resulting in the suppression of tumor growth and pulmonary metastasis.

Osteoblastic and osteolytic human osteosarcomas can be studied with a new xenograft mouse model producing spontaneous metastases

There is no animal model that reflects the histological and radiographical heterogeneity of osteosarcoma. We assessed seven osteosarcoma cell lines for their potential to develop orthotopic tumors and lung metastasis in SCID mice. Whereas radiologically, 143B developed osteolytic tumors, SaOS-LM7 developed osteoblastic primary tumors. The mineralization status was confirmed by assessing the alkaline phosphatase activity and the microarray expression profile. We herein report a xenograft orthotopic osteosarcoma mouse model to assess osteoblastic and osteolytic lesions, which may contribute in the search for new diagnostic and therapeutic approaches.

Osteoblastic and osteolytic human osteosarcomas can be studied with a new xenograft mouse model producing spontaneous metastases

There is no animal model that reflects the histological and radiographical heterogeneity of osteosarcoma. We assessed seven osteosarcoma cell lines for their potential to develop orthotopic tumors and lung metastasis in SCID mice. Whereas radiologically, 143B developed osteolytic tumors, SaOS-LM7 developed osteoblastic primary tumors. The mineralization status was confirmed by assessing the alkaline phosphatase activity and the microarray expression profile. We herein report a xenograft orthotopic osteosarcoma mouse model to assess osteoblastic and osteolytic lesions, which may contribute in the search for new diagnostic and therapeutic approaches.