Effects of endostar combined multidrug chemotherapy in osteosarcoma

Angiogenesis is closely related to tumor development and metastasis. Osteosarcoma is an angiogenesis-dependent tumor, and studies have shown that chemotherapy often induces angiogenesis. Endostatin is a broad spectrum angiogenesis inhibitor and, while pre-clinical trials have shown that the combination of endostatin with chemotherapy can enhance anti-tumor effects, this effect has not yet been shown in clinical trials. Here, we aimed to evaluate the clinical efficacy of endostar (ES, human recombinant endostatin) combined with chemotherapy in the treatment of osteosarcoma patients. A total of 116 newly diagnosed patients with osteosarcoma were enrolled in this study. All patients received 4cycles of chemotherapy with (54 cases) or without (62 cases) ES. ES was administered intravenously at a dose of 15mg/day for 2weeks during each cycle of chemotherapy. The tumors were removed by surgery after 2cycles of chemotherapy treatment, and their histologic response to chemotherapy was evaluated. Immunohistochemistry was used to measure VEGF and CD 31 expression. Chemotherapy increased VEGF expression and the presence of microvessels in osteosarcoma tissues compared with pre-chemotherapy. No significant difference was observed in the histologic response between the ES treatment and non-treatment groups. However, ES treatment significantly inhibited the chemotherapy-induced VEGF expression and presence of microvessels. The ES treatment did not affect the overall survival rate but did increase the event-free survival rate and decreased the occurrence of metastases. In conclusion, our results indicate that antiangiogenic therapy using ES has the potential to prevent the progression of metastases.

Low-grade central osteosarcoma of distal femur, resembling fibrous dysplasia

We report a case of a 32 year-old male, admitted for a lytic lesion of the distal femur. One month after the first X-ray, clinical and imaging deterioration was evident. Open biopsy revealed fibrous dysplasia. Three months later, the lytic lesion had spread to the whole distal third of the femur reaching the articular cartilage. The malignant clinical and imaging features necessitated excision of the lesion and reconstruction with a custom-made total knee arthroplasty. Intra-operatively, no obvious soft tissue infiltration was evident. Nevertheless, an excision of the distal 15.5 cm of the femur including 3.0 cm of the surrounding muscles was finally performed. The histological examination of the excised specimen revealed central low-grade osteosarcoma. Based on the morphological features of the excised tumor, allied to the clinical findings, the diagnosis of low-grade central osteosarcoma was finally made although characters of a fibrous dysplasia were apparent. Central low-grade osteosarcoma is a rare, well-differentiated sub-type of osteosarcoma, with clinical, imaging, and histological features similar to benign tumours. Thus, initial misdiagnosis is usual with the condition commonly mistaken for fibrous dysplasia. Central low-grade osteosarcoma is usually treated with surgery alone, with rare cases of distal metastases. However, regional recurrence is quite frequent after close margin excision.

Rational design of gold nanoparticles functionalized with carboranes for application in Boron Neutron Capture Therapy

In this paper we propose a bottom-up approach to obtain new boron carriers built with ortho-carborane functionalized gold nanoparticles (GNPs) for applications in Boron Neutron Capture Therapy. The interaction between carboranes and the gold surface was assured by one or two SH-groups directly linked to the boron atoms of the B10C2 cage. This allowed obtaining stable, nontoxic systems, though optimal biological performance was hampered by low solubility in aqueous media. To improve cell uptake, the hydrophilic character of carborane functionalized GNPs was enhanced by further coverage with an appropriately tailored diblock copolymer (PEO-b-PCL). This polymer also contained pendant carboranes to provide anchoring to the pre-functionalized GNPs. In vitro tests, carried out on osteosarcoma cells, showed that the final vectors possessed excellent biocompatibility joint to the capacity of concentrating boron atoms in the target, which is encouraging evidenced to pursue applications in vivo.

Surface proteomic analysis of differentiated versus stem-like osteosarcoma human cells

Cancer stem cell characterization represents a breakthrough in cancer research. Despite evidence showing the existence and the role of cancer stem cells in osteosarcoma (OS) onset and progression, little is known about their specific surface phenotype. To address this issue, we carried out a cytometric analysis with an antibody-array comprising 245 membrane proteins comparing the stem and differentiated OS cells. As experimental model, we chose the stem-like cell line 3aminobenzamide-OS and its parental, differentiated, cell line MG63. We identified 50 differentially expressed, 23 homogeneously expressed, and 172 not expressed proteins in the two cell line models, thus defining a surface protein signature specific for each of them. Furthermore, we selected ERK1/2 (p44/42 mitogen-activated protein kinases) as a potential pathway correlated with processes that characterize tumorigenic potential and stemness of 3aminobenzamide-OS cells.

Mitochondrial dysfunction and permeability transition in osteosarcoma cells showing the Warburg effect

Metabolic reprogramming in cancer is manifested by persistent aerobic glycolysis and suppression of mitochondrial function and is known as the Warburg effect. The Warburg effect contributes to cancer progression and is considered to be a promising therapeutic target. Understanding the mechanisms used by cancer cells to suppress their mitochondria may lead to development of new approaches to reverse metabolic reprogramming. We have evaluated mitochondrial function and morphology in poorly respiring LM7 and 143B osteosarcoma (OS) cell lines showing the Warburg effect in comparison with actively respiring Saos2 and HOS OS cells and noncancerous osteoblastic hFOB cells. In LM7 and 143B cells, we detected markers of the mitochondrial permeability transition (MPT), such as mitochondrial swelling, depolarization, and membrane permeabilization. In addition, we detected mitochondrial swelling in human OS xenografts in mice and archival human OS specimens using electron microscopy. The MPT inhibitor sanglifehrin A reversed MPT markers and increased respiration in LM7 and 143B cells. Our data suggest that the MPT may play a role in suppression of mitochondrial function, contributing to the Warburg effect in cancer.

Antibacterial Activity of Elephant Garlic and Its Effect against U2OS Human Osteosarcoma Cells

OBJECTIVE(S)

The present study was designed to investigate the antibacterial function and pharmacological effect of elephant garlic (Allium ampeloprasum var. ampeloprasum) on U2OS human osteosarcoma cells.

MATERIALS AND METHODS

Seven kinds of bacteria were reconstituted, inoculated and tested in this research to evaluate elephant garlic antibacterial activity. By the means of FACS analysis, cell proliferation assay, confocal laser scanning microscopy and Transwell migration assays, the effect of elephant garlic against U2OS human osteosarcoma cells was unveiled. Rerults: The antimicrobial activity of elephant garlic was stronger than ampicillin when used against Escherichia coli, Bacillus subtilis, Bacillus thuringiensis, Staphylococcus actinomycetes, and gray actinomycetes. Even at a very low concentration (12.5%), elephant garlic still had an antibacterial effect on common bacteria E. coli and S. aureus. The G0/G1 ratio of elephant garlic treated group cells increased while S phase decreased. Elephant garlic extract inhibited the growth of human osteosarcoma cells, U2OS, through preventing the transition from G1 phase to S phase. It reduced osteosarcoma cell, U2OS, invasion ability and significantly increased the proportion of apoptosis. It significantly affected the cytoskeleton generation.

CONCLUSION

Elephant garlic exhibits antibacterial property and has an inhibitory effect on osteosarcoma cells (U2OS) proliferation and cell activity, suggesting the mechanism of its anticancer effects on U2OS human osteosarcoma cells.

A causal role for circulating miR-34b in osteosarcoma

PURPOSE

To investigate the associations between plasma miR-34b/c expression levels and osteosarcoma (OS).

SUBJECTS AND METHODS

A case-control study was conducted in 133 patients with OS and 133 controls. MiR-34b/c levels were detected by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) assays. Genotyping of SNP rs4938723 was done using the TaqMan assay. The causal association was examined by mendelian randomization analysis.

RESULTS

Plasma miR-34b level was significantly lower in OS patients than in controls (P = 0.001). Expression levels of miR-34b in OS tissues decreased (P = 3.22 × 10(-4)) and was significantly related with its expression in plasma (r = 0.21, P = 0.004). Compared with wild-type TT genotype, the variant genotypes of rs4938723 TC/CC were significantly associated with increased OS risk (TC vs. TT: OR, 1.97 [95% CI: 1.40-2.55], P = 0.021; CC vs. TT: OR, 2.76 [95% CI: 2.00-3.53], P = 0.009; TC + CC vs. TT: OR, 2.16 [95% CI: 1.61-2.70], P = 0.006), consistent with its decreased effect on plasma miR-34b (TC vs. TT: -0.32 (-0.43, -0.21), P < 0.001; CC vs. TT: -0.70 (-0.84, -0.56), P < 0.001; TC + CC vs. TT: -0.42 (-0.53, -0.32), P < 0.001). Adjustment for miR-34b completely abolished the association between SNP rs4938723 and OS risk (P > 0.05). In addition, plasma expression levels of miR-34b were significantly decreased in the metastatic patients compared with that in the non-metastatic ones (P = 0.004).

CONCLUSION

Plasma miR-34b was causally associated with OS risk and related with its metastatic status, suggesting that plasma miR-34b might be a novel biomarker and a potential treatment target for OS.

TGF-β-induced expression of IGFBP-3 regulates IGF1R signaling in human osteosarcoma cells

Signaling pathways initiated by transforming growth factor-β (TGF-β) and insulin-like growth factors (IGFs) are important in osteosarcoma cell growth. We have investigated a role for endogenous IGF binding protein-3 (IGFBP-3) in mediating cross-talk between TGF-β receptor and type I IGF receptor (IGF1R) signaling pathways in MG-63 osteosarcoma cells. TGF-β1 indirectly activated the Ras/Raf/MAPK pathway and induced the expression of IGFBP-3, an important regulator of IGF1R activity. IGFBP-3 attenuated TGF-β1 activation of ERK1/2 and Akt in MG-63 cells, and inhibited TGF-β1-induced cell cycle progression and proliferation. This effect of IGFBP-3 was blocked by inhibiting IGF1R signaling. TGF-β1 phosphorylated Smad2 on the non-receptor substrate sites (Ser245/250/255). Blocking the TGF-β1-induced expression of IGFBP-3 enhanced pSmad2(Ser245/250/255) and increased its nuclear accumulation. These results suggest an important role for TGF-β1 in osteosarcoma cell growth, with the induction of IGFBP-3 by TGF-β1 serving in a negative-feedback loop to control cell growth by preventing activation of the IGF1R.

Functional epigenetic approach identifies frequently methylated genes in Ewing sarcoma

Using a candidate gene approach we recently identified frequent methylation of the RASSF2 gene associated with poor overall survival in Ewing sarcoma (ES). To identify effective biomarkers in ES on a genome-wide scale, we used a functionally proven epigenetic approach, in which gene expression was induced in ES cell lines by treatment with a demethylating agent followed by hybridization onto high density gene expression microarrays. After following a strict selection criterion, 34 genes were selected for expression and methylation analysis in ES cell lines and primary ES. Eight genes (CTHRC1, DNAJA4, ECHDC2, NEFH, NPTX2, PHF11, RARRES2, TSGA14) showed methylation frequencies of>20% in ES tumors (range 24-71%), these genes were expressed in human bone marrow derived mesenchymal stem cells (hBMSC) and hypermethylation was associated with transcriptional silencing. Methylation of NPTX2 or PHF11 was associated with poorer prognosis in ES. In addition, six of the above genes also showed methylation frequency of>20% (range 36-50%) in osteosarcomas. Identification of these genes may provide insights into bone cancer tumorigenesis and development of epigenetic biomarkers for prognosis and detection of these rare tumor types.

Dual effect of capsaicin on cell death in human osteosarcoma G292 cells

Thirty percent of osteosarcoma patients die within 5 years. New agents that induce apoptosis of osteosarcoma cells might be therapeutically useful. Here, we characterized the apoptotic mechanism induced by capsaicin in G292 osteosarcoma cells. Our results show that capsaicin induces an increase in the cytosolic Ca(2+) concentration which is independent of the extracellular Ca(2+) concentration and depletes intracellular Ca(2+) stores, suggesting the presence of endoplasmic reticulum transient receptor potential vanilloid receptor type 1. Capsaicin also activates the mitochondrial caspase 3-dependent death cascade. Rapamycin, an inhibitor of mammalian target of rapamycin, evokes autophagy, as do capsaicin or thapsigargin, a sarco(endo)plasmic reticulum Ca(2+) ATPase inhibitor that causes Ca(2+) store depletion. Capsaicin-induced cell death is completely inhibited by co-treatment with the pan-caspase inhibitor Z-VAD-fmk and increased by the autophagy inhibitor 3-methyladenine, suggesting the existence of an autophagy-dependent anti-apoptotic mechanism. Capsaicin also induces ERK phosphorylation, which acts as a downstream effector of autophagy. 3-Methyladenine or PD98059, an ERK kinase inhibitor, restores capsaicin-induced cell death in the presence of Z-VAD-fmk, suggesting that inhibition of autophagy activates a second cell death pathway that is caspase-independent. Taken together, our data show that capsaicin causes Ca(2+) depletion of intracellular Ca(2+) stores and simultaneously activates the mitochondrial caspase-dependent death cascade and autophagy-dependent ERK activation and that the latter counteracts a second death signaling pathway that is caspase-independent.

Downregulation of MCT1 inhibits tumor growth, metastasis and enhances chemotherapeutic efficacy in osteosarcoma through regulation of the NF-κB pathway

Monocarboxylate transporter isoform 1 (MCT1) is an important member of the proton-linked MCT family and has been reported in an array of human cancer cell lines and primary human tumors. MCT1 expression is associated with developing a new therapeutic approach for cancer. In this study, we initially showed that MCT1 is expressed in a variety of human osteosarcoma cell lines. Moreover, we evaluated the therapeutic response of targeting MCT1 using shRNA or MCT1 inhibitor. Inhibiting MCT1 delayed tumor growth in vitro and in vivo, including in an orthotopic model of osteosarcoma. Targeting MCT1 greatly enhanced the sensitivity of human osteosarcoma cells to the chemotherapeutic drugs adriamycin (ADM). In addition, we observed that MCT1 knockdown significantly suppressed the metastatic activity of osteosarcoma, including wound healing, invasion and migration. Further mechanistic studies revealed that the antitumor effects of targeting MCT1 might be related to the NF-κB pathway. Immunochemistry assay showed that MCT1 was an independent positive prognostic marker in osteosarcoma patients. In conclusion, our data, for the first time, demonstrate that MCT1 inhibition has antitumor potential which is associated with the NF-κB pathway, and high MCT1 expression predicates poor overall survival in patients with osteosarcoma.

MicroRNA-133a, downregulated in osteosarcoma, suppresses proliferation and promotes apoptosis by targeting Bcl-xL and Mcl-1

Deregulated microRNAs and their roles in cancer development have attracted much attention. Although miR-133a has been shown to be important in osteogenesis, its roles in osteosarcoma carcinogenesis and progression remain unknown. Hence, we focused on the expression and mechanisms of miR-133a in osteosarcoma development in this study. We found that miR-133a was downregulated in osteosarcoma cell lines and primary human osteosarcoma tissues, and its decrease was significantly correlated with tumor progression and prognosis of the patients. Functional studies revealed that restoration of miR-133a could reduce cell proliferation, promote cell apoptosis, and suppress tumorigenicity in osteosarcoma cell lines. Furthermore, bioinformatic prediction and experimental validation were applied to identify target genes of miR-133a, and the results revealed that the anti-tumor effect of miR-133a was probably due to targeting and repressing of Bcl-xL and Mcl-1 expression. Taken together, our data elucidate the roles of miR-133a in osteosarcoma pathogenesis and implicate its potential in cancer therapy.

Conversion of fused knee following distal femur tumor surgery to total knee arthroplasty

Conversion of knee arthrodesis to total knee arthroplasty is a difficult procedure accompanied by many complications due to soft tissue and extensor mechanism contracture and bone defects. We report two cases of distal femur osteosarcoma that had been undergone wide resection arthrodesis initially. Arthrodesis was converted to total knee arthroplasty with hinged prosthesis after many years. We describe patients' history and outline their surgical therapy and prognosis. To the best of the authors' knowledge, few cases have been previously reported in the literature.

A clinically relevant mouse model of canine osteosarcoma with spontaneous metastasis

BACKGROUND/AIM

Many patients with osteosarcoma (OS) will succumb to distant metastasis, often involving the lungs. Effective therapies for treating lung metastases depend on the availability of a clinically relevant pre-clinical model.

MATERIALS AND METHODS

Mice were surgically implanted with OS tumor fragments. The time course of primary tumor growth and subsequent spread to the lung were determined.

RESULTS

Following development of a lytic and proliferative primary bone lesion, tumor metastasized to the lung in the majority of mice. There was no evidence of tumor at three weeks, but 10 out of 11 mice ultimately developed secondary OS in the lung within 12 weeks.

CONCLUSION

Implantation of OS tumor fragments leads to the development of primary bone tumors and secondary lung metastases, recapitulating the clinical behavior of OS. This model offers an advantage over cell suspension injection models by precluding initial seeding of the lung with tumor cells.

Osteosarcoma of the maxilla: a rare case with unusual clinical presentation

Osteosarcoma (OS) is a malignant mesenchymal tumor, which rarely occurs in the maxilla. Although variable histologic and radiographic features of OS have been reported previously, in the majority of the cases painful swelling of the jaw is mentioned as the first clinical presentation. Furthermore, early diagnosis and wide surgical resection of the tumor are the most important determinant factors of prognosis. Therefore, the unusual clinical presentations of OS should be considered meticulously to expedite the diagnosis process. We describe a case of OS of the maxilla with extremely unusual presenta-tion in a 42-year-old female, that was initially designated as “epulis fissuratum”. Here, we highlight the importance of com-bining the clinical, radiographic and histopathologic examination to obtain a definitive diagnosis and also the significance ofearly effective surgical intervention in evaluation of pathologic lesions.

Role of surgical margin on local recurrence in high risk extremity osteosarcoma: a case-controlled study

BACKGROUND

The relationship between surgical margin and local recurrence (LR) in osteosarcoma patients with poor responses to chemotherapy is unclear. Moreover, the incidences of LR according to three different resection planes (bone, soft tissue, and perineurovascular) are not commonly known.

METHODS

We evaluated the incidence of LR in three areas. To assess whether there is a role of surgical margin on LR in patients resistant to preoperative chemotherapy, we designed a case (35 patients with LR) and control (70 patients without LR) study. Controls were matched for age, location, initial tumor volume, and tumor volume change during preoperative chemotherapy.

RESULTS

LR occurred at the soft tissues in 18 cases (51.4%), at the perineurovascular tissues in 11 cases (31.4%), and at the bones in six cases (17.2%). The proportion of inadequate perineurovascular margin was higher in the case group than in the control group (p = 0.01). Within case-control group (105 patients), a correlation between each margin status and LR at corresponding area was found in the bone (p < 0.001) and perineurovascular area (p = 0.001).

CONCLUSIONS

LR is most common in soft tissues. In patients showing similar unfavorable responses to chemotherapy, the losses of perineurovascular fat plane on preoperative magnetic resonance imaging may be a valuable finding in predicting LR.

Proteomics study of open biopsy samples identifies peroxiredoxin 2 as a predictive biomarker of response to induction chemotherapy in osteosarcoma

We attempted to identify biomarkers that would predict responsiveness of osteosarcoma (OS) to induction chemotherapy. Tumor tissues obtained by open biopsy before induction chemotherapy were investigated. On the basis of histological observations at the time of surgery and the Huvos grading system, 7 patients were classified as good responders and the other 6 as poor responders. Protein expression profiling was performed by two-dimensional difference gel electrophoresis. Among 3494 protein spots observed, the intensity of 33 spots was found to differ significantly between the two patient groups. The proteins for these 33 protein spots were identified by mass spectrometry. The higher expression of peroxiredoxin 2 (PRDX2) in poor responders was confirmed by Western blotting. Gene silencing assay demonstrated that reduced expression of PRDX2 was associated with increased sensitivity of OS cells to chemotherapeutic drugs such as methotrexate, doxorubicin and cisplatin. Moreover, siRNA-induced silencing of PRDX2 resulted in a decrease of cell proliferation, invasion and migration. These findings indicated that PRDX2 would be a candidate biomarker of response to induction chemotherapy. Measurement of PRDX2 in open biopsy samples before treatment may contribute to risk stratification therapy for OS.

BIOLOGICAL SIGNIFICANCE

The response of osteosarcoma patients to induction chemotherapy is critical because the prognosis of responders is quite favorable, whereas that of non-responders is poor. Although there are many therapeutic options for osteosarcoma, no parameter for predicting the response to induction chemotherapy has been available. We conducted a proteomics study aimed at developing a biomarker that would predict the response of osteosarcoma to induction chemotherapy. Using open biopsy samples obtained before chemotherapy, we conducted 2D-DIGE with our originally devised large-format electrophoresis apparatus and identified peroxiredoxin 2 (PRDX2) as a novel predictive biomarker. The diagnostic performance of PRDX2 was confirmed by ROC analysis, and its functional properties were investigated in a series of in vitro functional assays. Our findings indicate the possible application of PRDX2 as a predictive biomarker in patients with osteosarcoma.

A case of intradural osteosarcoma of the spine

BACKGROUND CONTEXT

Intradural-extramedullary spinal tumors and extradural osteosarcomas are both rare entities. Only one case of primary intradural-extramedullary osteosarcoma of the spine has been previously reported. This is the second reported case.

PURPOSE

To describe a case of primary intradural-extramedullary osteosarcoma of the spine associated with rapid clinical deterioration.

STUDY DESIGN

Case report of a 70-year-old woman who presented with a constellation of neurologic symptoms.

METHODS

Review of patient files, radiographic studies, surgical images, histopathology, and relevant literature.

RESULTS

The patient underwent tumor debulking but exhibited rapid, postsurgical, functional deterioration and died within 6 weeks. This case and the only previous case of its kind both occurred in individuals with a remote history of iophendylate (Myodil) myelogram.

CONCLUSIONS

Primary intradural-extramedullary extraosseous osteosarcoma of the spine is an exceedingly rare entity with no established management approach. Iophendylate myelography may be implicated in the etiology of this tumor type.

Adverse impact of regional lymph node involvement in osteosarcoma

BACKGROUND

Metastatic dissemination in osteosarcoma occurs haematogenously, though regional lymph node involvement is rarely reported. We investigated incidence, patient characteristics and survival for patients with osteosarcoma and regional lymph node involvement at diagnosis.

METHODS

We identified 2748 cases of high-grade osteosarcoma with available information regarding regional lymph node involvement in the Surveillance Epidemiology and End Results database from 1973 to 2009. Demographics were compared using chi-squared tests or t-tests. Overall survival was estimated using Kaplan-Meier method and compared with log-rank tests. Multivariate analysis of overall survival was performed using Cox proportional hazards methods.

RESULTS

There were 74 patients (2.7%) with regional lymph node involvement at diagnosis of whom 19 (0.7%) were pathologically confirmed. Patients with regional node involvement were more likely to have extraskeletal tumours, distant metastases, tumours arising outside the lower extremity (p<0.0001 for all comparisons) and larger tumours (p=0.033). Five-year overall survival in those with and without regional node involvement was 10.9% (95% confidence interval (CI) 4.6-20.4) and 54.3% (95% CI 52.2-56.4; p<0.0001). In multivariate analysis, regional node involvement remained predictive of inferior survival after controlling for differences in metastatic status, age, tumour site and extraskeletal origin (hazard ratio 2.05, 95% CI 1.57-2.67; p<0.0001). Similar survival results were found when the analysis was restricted to patients with pathologically confirmed positive or negative regional lymph nodes.

CONCLUSION

This analysis confirms that regional node involvement is a significant adverse prognostic factor that is independent of metastatic status, extraskeletal origin, age and tumour site.

Role of positron emission tomography/computed tomography in bone malignancies

This article presents an overview of positron emission tomography combined with computed tomography (PET/CT) imaging of bone tumors for the practicing radiologist. The clinical roles and utility of (18)F-labeled fluorodeoxyglucose PET/CT in patients with primary bone tumors, osseous metastases, and multiple myeloma are reviewed. The clinical and research data supporting the utility of PET/CT in the evaluation of skeletal malignancies continues to grow.

The β5/focal adhesion kinase/glycogen synthase kinase 3β integrin pathway in high-grade osteosarcoma: a protein expression profile predictive of response to neoadjuvant chemotherapy

To date, chemosensitivity to neoadjuvant chemotherapy of patients with high-grade osteosarcoma is evaluated on surgical resection by evaluation of the percentage of necrotic cells. As yet, no predictive profile of response to chemotherapy has been used in clinical practice. Because we have previously shown that the integrin pathway controls genotoxic-induced cell death and hypoxia, we hypothesized that in primary biopsies, expression of proteins involved in this pathway could be associated with sensitivity to neoadjuvant chemotherapy in high-grade osteosarcoma. We studied β1, β3, and β5 integrin expression and integrin-linked kinase, focal adhesion kinase (FAK), glycogen synthase kinase 3β (GSK3β), Rho B, angiopoietin-2, β-catenin, and ezrin expression by immunohistochemistry in 36 biopsies of osteosarcomas obtained before treatment. All patients received a chemotherapy regimen in the neoadjuvant setting. An immunoreactive score was assessed, combining the percentage of positive tumor cells and staining intensity. We evaluated the correlation of the biomarkers with response to chemotherapy, metastasis-free survival, and overall survival. A combination of 3 biomarkers (β5 integrin, FAK, and GSK3β) discriminated good and poor responders to chemotherapy, with the highest area under the curve (89.9%; 95% confidence interval, 77.4-1.00) and a diagnostic accuracy of 90.3%. Moreover, high expression of ezrin was associated with an increased risk of metastasis (hazard ratio, 3.93; 95% confidence interval, 1.19-12.9; P = .024). We report a protein expression profile in high-grade osteosarcoma associating β5 integrin, FAK, and GSK3β that significantly correlates with poor response to neoadjuvant chemotherapy. This biomarker profile could help select patients for whom an alternative protocol using inhibitors of this pathway can be proposed.

The metastatic behavior of osteosarcoma by gene expression and cytogenetic analyses

Osteosarcoma is a malignant bone tumor with high metastatic potential. Metastasis at diagnosis is the most significant prognostic factor in predicting the clinical outcome of osteosarcoma. We compared the gene expression of metastases that were present at the time of initial diagnosis to those developed later in the course of the disease. We used quantitative real-time polymerase chain reaction to evaluate the gene expression of MDM2, CXCR4, RANKL, RB1, and OSTERIX in 98 samples of osteosarcoma taken from 47 patients (74 metastases and 24 primary tumors) and 30 nonmalignant lung tissues surrounding osteosarcoma metastases. In addition, we investigated the copy number changes of RB1 and MDM2 genes in 12 primary cultures of pulmonary metastases of osteosarcoma, using interphase fluorescence in situ hybridization. Metastases from metastatic patients at diagnosis were characterized by low expression of RB1 and RANKL (P = .0009 and P = .0109, respectively) and overexpression of CXCR4 and MDM2 (P = .0389 and P = .0325, respectively). The loss of RANKL and gain of CXCR4 could also be detected in the primary tumors of metastatic patients at diagnosis (P = .0121 and P = .0264, respectively). Thus, some early genetic events such as the loss of RANKL and the gain of CXCR4 expressions probably facilitate the metastatic progression concomitant with the primary tumor establishment, supporting the role of the CXCR4 receptor in directing osteosarcoma metastases to the lung. On the other hand, late events such as the loss of RB1 and gain of MDM2, crucial regulators of cell cycle, appear to be related to the final mechanisms contributing to the metastatic establishment of osteosarcoma.

Epirubicin-mediated expression of miR-302b is involved in osteosarcoma apoptosis and cell cycle regulation

Epirubicin is widely used in osteosarcoma chemotherapy. Growing evidence indicates that the microRNA (miRNA) expression levels which are induced by chemotherapeutic agents play an important role in osteosarcoma development and progression. In this study we investigate the alterations of miRNA expression in the osteosarcoma cells after epirubicin treatment and whether miRNAs can enhance its anti-osteosarcoma effect. After epirubicin exposure, microarray shows 40 miRNAs are differentially expressed in osteosarcoma cells including 24 down-regulated miRNAs. Notably, miR-302b, which is stably low-expressed in osteosarcoma, could be induced by the epirubicin. Furthermore, we find that miR-302b can inhibit the osteosarcoma cell proliferation, promote cell apoptosis and cell cycle arrest MiR-302b can activate caspase-3 and regulate the Akt/pAkt, Bcl-2, Bim expression to increase the cell apoptosis. Meanwhile, miR-302b also attenuates cyclin D1 and CDKs expression to induce cell cycle arrest. Therefore, our results suggest miR-302b can play an essential role in osteosarcoma treatment as a potential tumor suppressor.

Sprouty2 but not Sprouty4 is a potent inhibitor of cell proliferation and migration of osteosarcoma cells

As negative regulators of receptor tyrosine kinase-mediated signalling, Sprouty proteins fulfil important roles during carcinogenesis. In this report, we demonstrate that Sprouty2 protein expression inhibits cell proliferation and migration in osteosarcoma-derived cells. Although earlier reports describe a tumour-promoting function, these results indicate that Sprouty proteins also have the potential to function as tumour suppressors in sarcoma. In contrast to Sprouty2, Sprouty4 expression failed to interfere with proliferation and migration of the osteosarcoma-derived cells, possibly due to a less pronounced interference with mitogen-activated protein kinase activity. Sequences within the NH2-terminus are responsible for the specific inhibitory function of Sprouty2 protein.

Synergistic apoptotic effect of crocin and cisplatin on osteosarcoma cells via caspase induced apoptosis

Crocin is well-known traditional Chinese medicine which is extracted from saffron. However, its role in osteosarcoma has not been well understood. Therefore, we used crocin and cisplatin individually or jointly on MG63 and OS732 cells so as to explore whether crocin could induce cellular apoptosis and suppress the ability of invasion of osteosarcoma cells. Cell survival rates, changes of cellular shape, cell apoptosis and cell invasion were analyzed, respectively, by 3-(4,5)-dimethylthiahiazo (-z-y1)-2,5-di- phenytetrazoliumromide (MTT) assay, inverted phase contrast microscope and fluorescence microscope, flow cytometry, and Transwell invasion chamber methods. The expressions of caspase-3 and caspase-8 were detected by Western blot. The survival rate of combined application was significantly lower than that of the individual application. Apoptosis-inducing effect of combined application was much stronger than that of individual application. The invasion ability of MG63 and OS732 cells was restrained significantly in the combined group compared with the individual group and control group. Combined group has the effect of up-regulating the expressions of cleaved-caspase-3 and caspase-8. The results suggested that combination of crocin and cisplatin has a strong killing effect on osteosarcoma cells and suppresses the ability of invasion of MG63 and OS732 cells which might be related to up-regulate the expression of caspase-3 and caspase-8.

Immunohistochemical expression of vegf and her-2 proteins in osteosarcoma biopsies

OBJECTIVES:

To identify the prevalence of erbB-2 and vascular endothelial growth factor (VEGF) in osteosarcoma biopsies and to correlate them with possible prognosis factors.

METHODS:

Retrospective study conducted at the Hospital do Câncer de Barretos-SP including 27 osteosarcoma biopsies immunohistochemically stained for VEGF and erbB-2. The pathological characteristics were collected from medical records of patients to correlate with markers.

RESULTS:

In 27 biopsies, four overexpressed VEGF and three overexpressed erbB-2. Two thirds of patients had no metastases. Almost all patients with overexpression of VEGF showed metastases. Overexpression of erbB-2 was inversely related to the presence of metastases. There was no significant association between markers and prognosis.

CONCLUSION:

We identified a low prevalence of erbB-2 and VEGF in the sample. There was no significant association between overexpression of markers and pathological features. A larger sample and a longer follow-up, in addition to using new laboratory techniques can determine the real expression of VEGF and erbB-2 and its role in osteosarcoma. Level of Evidence III, Case-Control Study.

Selaginella tamariscina (Beauv.) possesses antimetastatic effects on human osteosarcoma cells by decreasing MMP-2 and MMP-9 secretions via p38 and Akt signaling pathways

Selaginella tamariscina is a traditional medicinal plant for treatment of some advanced cancers in the Orient. However, the effect of S. tamariscina on metastasis of osteosarcoma and the underlying mechanism remain unclear. We tested the hypothesis that S. tamariscina suppresses cellular motility, invasion and migration and also investigated its signaling pathways. This study demonstrates that S. tamariscina, at a range of concentrations (from 0 to 50 μg/mL), concentration-dependently inhibited the migration/invasion capacities of three osteosarcoma cell lines without cytotoxic effects. Zymographic and western blot analyses revealed that S. tamariscina inhibited the matrix metalloproteinase (MMP)-2 and MMP-9 enzyme activity, as well as protein expression. Western blot analysis also showed that S. tamariscina inhibits phosphorylation of p38 and Akt. Furthermore, SB203580 (p38 inhibitor) and LY294002 (PI3K inhibitor) showed the similar effects as S. tamariscina in U2OS cells. In conclusion, S. tamariscina possesses an antimetastatic activity in osteosarcoma cells by down-regulating MMP-2 and MMP-9 secretions and increasing TIMP-1 and TIMP-2 expressions through p38 and Akt-dependent pathways. S. tamariscina may be a powerful candidate to develop a preventive agent for osteosarcoma metastasis.

Postradiation osteosarcoma in an older prostate cancer survivor: case study and literature review with emphasis on geriatric principles

The aging population and the increasing number of cancer survivors will likely be associated with more second primary malignancies due to prior cancer treatment. Since the incidence of most cancers increases with age, these treatment-associated second malignancies will likely disproportionately impact older adults. Here, we present the case of a 78-year-old man with a history of localized prostate cancer treated with external beam radiation therapy 11 years prior, who developed osteosarcoma of the ilium. Geriatric screening showed a fit older male with few comorbidities, functional independence and no other geriatric syndromes. Given the patient's preference for a limb-sparing operation, neoadjuvant chemotherapy was undertaken. With the paucity of clinical trial data on osteosarcoma in older adults, the patient was given a regimen of carboplatin (substituted for cisplatin), doxorubicin and methotrexate. Unfortunately, he developed methotrexate-induced acute kidney injury. Chemotherapy was discontinued, and he proceeded to hemipelvectomy. His postoperative course was marked by numerous complications, including delirium, depression and recurrent hospitalizations. He ultimately developed a local recurrence and elected for hospice care. This case highlights the challenges of managing older adults with treatment-associated malignancies. Clinicians face a lack of clinical trial data from which to extrapolate limitations of therapeutic options because of prior therapy and a limited ability to precisely predict which elders will experience adverse outcomes. Better approaches are needed to help older patients make decisions which fulfill their goals of care and to improve the care of older adults with treatment-associated malignancies.

Reoxygenation using a novel CO2 therapy decreases the metastatic potential of osteosarcoma cells

Osteosarcoma is the most common primary solid malignant bone tumor. Despite substantial improvements in surgery and chemotherapy, metastasis remains a major cause of fatal outcomes, and the molecular mechanisms of metastasis are still poorly understood. Hypoxia, which is common in malignant tumors including osteosarcoma, increases expressions of hypoxia inducible factor (HIF)-1α, matrix metalloproteinase (MMP)-2 and MMP-9, and can induce invasiveness. As we previously showed a novel transcutaneous CO2 application to decrease HIF-1α expression and induce apoptosis in malignant fibrous histiocytoma, we hypothesize that transcutaneous CO2 application could suppress metastatic potential of osteosarcoma by improving hypoxic conditions. Here, we examined the effects of transcutaneous CO2 application on apoptosis, and development of pulmonary metastasis using a highly metastatic osteosarcoma cell line, LM8. Transcutaneous CO2 application significantly decreased tumor growth and pulmonary metastasis in LM8 cells. Apoptotic activity increased, and intratumoral hypoxia was improved with decreased expressions of HIF-1α, MMP-2 and MMP-9, significantly, in the CO2-treated tumors. In conclusion, we found that transcutaneous CO2 application can induce tumor cell apoptosis and might suppress pulmonary metastasis by improvement of hypoxic conditions with decreased expressions of HIF-1α and MMPs in highly metastatic osteosarcoma cell. These findings strongly indicate that this novel transcutaneous CO2 therapy could be a therapeutic breakthrough for osteosarcoma patients.

MicroRNA-34c inversely couples the biological functions of the runt-related transcription factor RUNX2 and the tumor suppressor p53 in osteosarcoma

Osteosarcoma (OS) is a primary bone tumor that is most prevalent during adolescence. RUNX2, which stimulates differentiation and suppresses proliferation of osteoblasts, is deregulated in OS. Here, we define pathological roles of RUNX2 in the etiology of OS and mechanisms by which RUNX2 expression is stimulated. RUNX2 is often highly expressed in human OS biopsies and cell lines. Small interference RNA-mediated depletion of RUNX2 inhibits growth of U2OS OS cells. RUNX2 levels are inversely linked to loss of p53 (which predisposes to OS) in distinct OS cell lines and osteoblasts. RUNX2 protein levels decrease upon stabilization of p53 with the MDM2 inhibitor Nutlin-3. Elevated RUNX2 protein expression is post-transcriptionally regulated and directly linked to diminished expression of several validated RUNX2 targeting microRNAs in human OS cells compared with mesenchymal progenitor cells. The p53-dependent miR-34c is the most significantly down-regulated RUNX2 targeting microRNAs in OS. Exogenous supplementation of miR-34c markedly decreases RUNX2 protein levels, whereas 3'-UTR reporter assays establish RUNX2 as a direct target of miR-34c in OS cells. Importantly, Nutlin-3-mediated stabilization of p53 increases expression of miR-34c and decreases RUNX2. Thus, a novel p53-miR-34c-RUNX2 network controls cell growth of osseous cells and is compromised in OS.

High grade osteosarcoma on a background of trichorhinophalangeal syndrome: A family perspective

Trichorhinophalangeal syndrome (TRPS) is a rare genetic disorder with typical craniofacial and skeletal abnormalities. Three main subtypes have been described. All variations of the condition affect the hair (tricho), nose (rhino) and fingers (phalangeal). The diagnosis is usually made through clinical examination augmented by hand radiographs that reveal characteristic cone-shaped epiphyses Sporadic case reports detailing TRPS have been described in the literature. We describe the first report of high-grade osteosarcoma presenting in two members of the same family with trichorhinophalangeal syndrome (TRPS).

Successful management of early recurrence after surgery for primary rib osteosarcoma in an adult

Primary osteosarcoma is a common malignant bone tumour that principally affects the long bones, but relatively rare in flat bones, in children and adolescents. This study presents a rare case of primary rib osteosarcoma in a 59-year old man. The patient underwent second radical excision of the tumour due to a short time relapse after the first operation. Chest wall reconstruction, neoadjuvant chemotherapy before the second operation and postoperative chemotherapy were also performed. To date, 5 months have passed with no recurrence being observed.

MicroRNA-199b-5p is involved in the Notch signaling pathway in osteosarcoma

MicroRNAs (miRNAs) play important roles in the development, differentiation, and function of different cell types and in the pathogenesis of various human diseases. miRNAs are differentially expressed in normal and cancer cells. The investigation of miRNA expression between healthy subjects and patients with osteosarcoma is crucial for future clinical trials. We performed miRNA microarray analysis on 8 formalin-fixed, paraffin-embedded osteosarcoma tissue samples. We confirmed the results of the microarray analysis using reverse transcription polymerase chain reaction. miRNA profiling of osteosarcoma tissue samples showed that expression of 10 miRNAs had increased 10-fold compared with normal controls. Among the 10 miRNAs, 3 miRNAs (miR-199b-5p, miR-338-3p, and miR-891a) were confirmed to have been up-regulated by reverse transcription polymerase chain reaction. After transfection of 4 osteosarcoma cell lines with miR-199b-5p inhibitor, the expression of Notch pathway components in the transfected cell lines was changed. These results revealed that miR-199b-5p plays a role in Notch signaling in osteosarcoma. Recently, the inhibition of Notch and HES1 signaling has been suggested as a potential therapeutic strategy to prevent metastasis in human osteosarcoma. Taken together with our results, we suggest that miR-199b-5p inhibitor may also be a therapeutic option for osteosarcoma.

Fibrocartilaginous intramedullary bone forming tumor of the distal femur mimicking osteosarcoma

Fibrocartilaginous dysplasia (FCD) has occasionally led to a misdiagnosis and wrong decision which can significantly alter the outcome of the patients. A 9-yr-old boy presented with pain on his left distal thigh for 6 months without any trauma history. Initial radiographs showed moth eaten both osteolytic and osteosclerotic lesions and biopsy findings showed that the lesion revealed many irregular shaped and sclerotic mature and immature bony trabeculae. Initial diagnostic suggestions were varied from the conventional osteosarcoma to low grade central osteosarcoma or benign intramedullary bone forming lesion, but close observation was done. This study demonstrated a case of unusual fibrocartilaginous intramedullary bone forming tumor mimicking osteosarcoma, so that possible misdiagnosis might be made and unnecessary extensive surgical treatment could be performed. In conclusion, the role of orthopaedic oncologist as a decision maker is very important when the diagnosis is uncertain.

Biological characterization of preclinical Bioluminescent Osteosarcoma Orthotopic Mouse (BOOM) model: A multi-modality approach

Osteosarcoma (OS) is a bone malignancy that affects children and adolescents. It is a highly aggressive tumor and typically metastasizes to lungs. Despite aggressive chemotherapy and surgical treatments, the current 5 year survival rate is 60–70%. Clinically relevant models are needed to understand OS pathobiology, metastatic progression from bones to lungs, and ultimately, to develop more efficacious treatment strategies and improve survival rates in OS patients with metastasis. The main goal of this study was to develop and characterize an in vivo OS model that will allow non-invasive tracking of tumor progression in real time, and aid in studying OS pathobiology, and screening of potential therapeutic agents against OS. In this study, we have used a multi-modality approach using bioluminescent imaging, electron microscopy, micro-computed tomography, and histopathology to develop and characterize a preclinical Bioluminescent Osteosarcoma Orthotopic Mouse (BOOM) model, using 143B human OS cell line. The results of this study clearly demonstrate that the BOOM model represents the clinical disease as evidenced by a spectrum of changes associated with tumor establishment, progression and metastasis, and detection of known OS biomarkers in the primary and metastatic tumor tissue. Key novel findings of this study include: (a) multimodality approach for extensive characterization of the BOOM model using 143B human OS cell line; (b) evidence of renal metastasis in OS orthotopic model using 143B cells; (c) evidence of Runx2 expression in the metastatic lung tissue; and (d) evidence of the presence of extracellular membrane vesicles and myofibroblasts in the BOOM model.

Osteosarcoma of mandible

Osteosarcomas are malignant neoplasms of the bone which commonly affect the long bones. The involvement of the jaws are rarely noticed. These neoplasms often shows a typical clinical behaviour as well as varied radiological appearances. Similarly, their histological growth pattern can be quite diverse. Confirmation of the final diagnosis of an osteosarcoma often requires a histopathological examination of the multiple biopsy specimens and vigorous discussion amongst the experts. All these clinical features, radiographic appearances and histological diagnostic difficulties were encountered in a case of osteosarcoma of the mandible in a 29-year old female.

Is (99m)Tc-MIBI scintigraphy a predictor of response to pre-operative neoadjuvant chemotherapy in Osteosarcoma?

OBJECTIVES

Multidrug resistance (MDR), which may be due to the over expression of P-glycoprotein (Pgp) and/or MRP, is a major problem in neoadjuvant chemotherapy of osteosarcoma. The aim of this study was to investigate the role of Tc-99m MIBI scan for predicting the response to pre-operative chemotherapy.

METHODS

Twenty-five patients (12 males and 13 females, aged between 8 and 52y) with osteosarcoma were studied. Before the chemotherapy, planar (99m)Tc-MIBI anterior and posterior images were obtained 10-min [tumor-to-background ratio: (T1/B1)10min] and 3-hr after tracer injection. After completion of chemotherapy, again (99m)Tc-MIBI scan was performed at 10-min after tracer injection. In addition to calculation of decay corrected tumor to background (T/B) ratios, using the 10-min and 3-hr images of the pre-chemotherapy scintigraphy, percent wash-out rate (WR%) of (99m)Tc-MIBI was calculated. Using the 10-min images of the pre- and post-chemotherapy scans, the percent reduction in uptake at the tumor site after treatment (Red%) was also calculated. Then after surgical resection, tumor response was assessed by percentage of necrosis.

RESULTS

All patients showed significant (99m)Tc-MIBI uptake in early images. Only 9 patients showed good response to chemotherapy (necrosis≥90%) while 16 patients were considered as non-responder (necrosis<90%). There was no statistical significant difference between non-responders and responders in (T1/B1)10min.There was a significant negative correlation between WR% and percentage of necrosis (P=0.001). On the other hand, there was a significant correlation between Red% and percentage of necrosis (P<0.001).There was also statistical significant difference in WR% and Red% between non-responders and responders (both P< 0.001).

CONCLUSION

Washout rate of (99m)Tc-MIBI in pre-chemotherapy scintigraphy as well as Red% using pre- and post-chemotherapy MIBI scintigraphy are useful methods for predicting response to neoadjuvant chemotherapy.

Beyond Palliation: Therapeutic Applications of 153Samarium-EDTMP

Primary and metastatic malignant bone lesions result in significant pain and disability in oncology patients. Targeted bone-seeking radioisotopes including ¹⁵³Samarium ethylene-diamine-tetramethylene-phosphonic acid (¹⁵³Sm-EDTMP) have been shown to effectively palliate bone pain, often when external beam radiotherapy (EBRT) is not feasible. However, recent evidence also suggests ¹⁵³Sm-EDTMP has cytotoxic activity either alone or in combination with chemotherapy or EBRT. ¹⁵³Sm-EDTMP may be useful as anti-neoplastic therapy apart from pain palliation in a variety of malignancies. For prostate cancer patients, several phase I and II clinical trials have shown that combined ¹⁵³Sm-EDTMP and docetaxel-based chemotherapy can result in >50% decrease in prostate-specific antigen with manageable myelosuppression. In hematologic malignancies, ¹⁵³Sm-EDTMP produced clinical responses when combined with bortezomib in multiple myeloma. ¹⁵³Sm-EDTMP also can be used with myeloablative chemotherapy for marrow conditioning prior to stem cell transplant. In osteosarcoma, ¹⁵³Sm-EDTMP infusion delivers radiation to multiple unresectable lesions simultaneously and provides local cytotoxicity without soft tissue damage that can be combined with chemotherapy or radiation. Prior to routine incorporation of ¹⁵³Sm-EDTMP into therapeutic regimens, we must learn how to ensure optimal delivery to tumors, determine which patients are likely to benefit, improve our ability to assess clinical response in bone lesions and further evaluate the efficacy ¹⁵³Sm-EDTMP in combination with chemotherapy, radiation and novel targeted agents.

Epidermal growth factor receptor: is it a feasible target for the treatment of osteosarcoma?

Purpose

Features of epidermal growth factor receptor (EGFR) expression in osteosarcoma and in vitro efficacies of EGFR inhibitors against osteosarcoma cells were evaluated.

Materials and Methods

Thirty biopsy samples of osteosarcoma patients were retrospectively analyzed for EGFR protein expression by immunohistochemistry. Relationships between EGFR expression and clinicopathologic characteristics and treatment outcomes were evaluated. Four osteosarcoma cell lines were analyzed for EGFR and p-EGFR expression by western blotting. Efficacies of gefitinib and BIBW2992 on osteosarcoma cells were evaluated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Tyrosine kinase domains in exons 18 to 21 were sequenced and gene expression analyses of EGFR and PTEN were performed in four osteosarcoma cell lines.

Results

EGFR protein was expressed in 27 (90%) samples (6 low, 12 intermediate, 9 high) and in three cell lines. Intermediate or high staining for EGFR was related to a tumor volume<150 mL (p<0.001) and histologic subtype other than osteoblastic type (p=0.03). However, EGFR expression was not associated with histologic response to preoperative chemotherapy or survival. Gefitinib and BIBW 2992 did not have any significant inhibitory effect on cell viabilities. DNA sequencing analysis revealed three osteosarcoma cell lines have single base changes at codon 2361 of exon 20 (G to A), without affecting translation results. Furthermore, no mutation was found to be associated with constitutive EGFR activation.

Conclusion

In the present study, gefitinib and BIBW2992 were not effective against osteosarcoma cells. However, as osteosarcoma cells express EGFR, further studies are necessary to explore the potential of other therapeutic agents targeting EGFR.

DACH1 Expresison in Osteosarcoma and Its Relationship with Proliferation and Angiogenesis

The aim of this study was to investigate the expression of DACH1 in osteosarcoma as well as its relationship with cell proliferation and angiogenesis in the tumor. DACH1 expression was detected by immunohistochemical staining in the serial sections of the osteosarcoma. The microvessel density (MVD) was counted by CD34 immunohistochemical staining, and immunohistochemical staining of PCNA staining showed the cell proliferation. The impacts of DACH1 expression on tumor proliferation and angiogenesis were evaluated by statistics. The DACH1 had different expression patterns in different osteosarcoma. Conventional osteosarcoma showed stronger DACH1 staining (conventional vs. parosteal: P = 0.037; conventional vs. periosteal: P = 0.028) and more PCNA-positive tumor cells than parosteal and periosteal osteosarcoma (conventional vs. parosteal: P = 0.041; conventional vs. periosteal: P = 0.045), the difference was significant. In addition, conventional osteosarcoma showed more cytoplasmic staining of DACH1 than parosteal and periosteal (conventional vs. parosteal: P = 0.023; conventional vs. periosteal: P = 0.030). Parosteal and periosteal osteosarcoma showed no significant difference in DACH1 expression and cell proliferation index. On the other hand, DACH1 different expression patterns showed significantly different impacts on angiogenesis. In spite of the different subtypes of osteosarcoma, the MVD showed a significant difference in cytoplasmic and nuclear expression patterns of DACH1 (nuclear expression vs. cytoplasmic expression: 5.72 ± 1.19 vs. 9.65 ± 1.24, P = 0.042). Moreover, in the conventional osteosarcoma, the MVD also showed a significant difference in DACH1 cytoplasmic and nuclear staining (nuclear expression vs. cytoplasmic expression: 5.58 ± 0.71 vs. 13.65 ± 1.30, P = 0.019). However, the DACH1 expression intensity showed no significant different impacts on MVD of all kinds of osteosarcoma. DACH1 had different expression patterns and intensity. Cytoplasmic and nuclear expression of DACH1 might play different roles in cell proliferation and angiogenesis of osteosarcoma. Cytoplasmic DACH1 might promote cell proliferation and be associated with angiogenesis.

Current concepts in surgical treatment of osteosarcoma

Osteosarcoma is the most common malignant primary neoplasm of bone. For an optimal oncological outcome, surgical removal of tumor is an essential component of its multidisciplinary treatment. Limb salvage surgery has long been established as the standard of care for osteosarcoma. While limb-salvaging techniques have acceptable rates of disease control, amputation remains a valid procedure in selected cases. In current orthopedic oncology practice, the focus is on optimizing the balance between preservation of form and function of the limb and adequate oncological clearance at the same time. Improving the functional outcome and longevity of reconstructive procedures also remains a challenge.

Perspectives on cancer stem cells in osteosarcoma

Osteosarcoma is an aggressive pediatric tumor of growing bones that, despite surgery and chemotherapy, is prone to relapse. These mesenchymal tumors are derived from progenitor cells in the osteoblast lineage that have accumulated mutations to escape cell cycle checkpoints leading to excessive proliferation and defects in their ability to differentiate appropriately into mature bone-forming osteoblasts. Like other malignant tumors, osteosarcoma is often heterogeneous, consisting of phenotypically distinct cells with features of different stages of differentiation. The cancer stem cell hypothesis posits that tumors are maintained by stem cells and it is the incomplete eradication of a refractory population of tumor-initiating stem cells that accounts for drug resistance and tumor relapse. In this review we present our current knowledge about the biology of osteosarcoma stem cells from mouse and human tumors, highlighting new insights and unresolved issues in the identification of this elusive population. We focus on factors and pathways that are implicated in maintaining such cells, and differences from paradigms of epithelial cancers. Targeting of the cancer stem cells in osteosarcoma is a promising avenue to explore to develop new therapies for this devastating childhood cancer.

Maxillary osteosarcoma masquerading as chondromyxoid fibroma: report of a case

Osteosarcomas are highly malignant bone tumours. Its appearance in craniofacial bones is a rare entity and accounts for only 1% of all head and neck malignancies. We present an uncommon case report of a 42 year old male patient with osteosarcoma of left maxilla, which was successfully excised under general anesthesia. The patient reported to us with a history of pain, swelling, pus discharge and tooth extraction, which led to the differential diagnosis of suppurative osteomyelitis, dentoalveolar abscess, benign odontogenic tumour, an infected cyst etc. Histopathological examination of incisional biopsy was reported as chondromyxoid fibroma which is a rare benign tumour. However the excisional biopsy specimen was reported as osteosarcoma of maxilla. The clinical presentation, diagnostic challenges and its therapeutic approach are addressed. This case serves to emphasize the need to recognize osteosarcoma when it presents in unexpected locations, especially because of its rarity.

The role of imaging for the surgeon in primary malignant bone tumors of the chest wall

Primary malignant chest wall tumors are rare. The most frequent primary malignant tumor of the chest wall is chondrosarcoma, less common are primary bone tumors belonging to the Ewing Family Bone Tumors (EFBT), or even rarer are osteosarcomas. They represent a challenging clinical entities for surgeons as the treatment of choice for these neoplasms is surgical resection, excluding EFBT which are normally treated by a multidisciplinary approach. Positive margins after surgical procedure are the principal risk factor of local recurrence, therefore to perform adequate surgery a correct preoperative staging is mandatory. Imaging techniques are used for diagnosis, to determine anatomic site and extension, to perform a guided biopsy, for local and general staging, to evaluate chemotherapy response, to detect the presence of a recurrence. This article will focus on the role of imaging in guiding this often difficult surgery and the different technical possibilities adopted in our department to restore the mechanics of the thoracic cage after wide resections.

Non surgical treatment of sacral osteosarcoma

Osteosarcoma may rarely originate from the axial bones such as pelvis or vertebrae. In some pelvic and most vertebral primary tumors, resection often is not possible completely. In general, these tumors cannot be resected with negative margins so they need additional radiotherapy and chemotherapy, but results are unfavourable because of poor local control and high incidence of distant metastases. This is a case report of sacral osteosarcoma which was treated successfully with chemotherapy and radiation therapy. The patient is a 14-year-old boy with a large osteosarcoma tumor in the first sacral vertebral body, with extra skeletal extension. The patient took radiotherapy (6000 centigray) plus chemotherapy regimen consisting of doxorubicin and cisplatin. In the last follow up 48 months later, the patient was completely asymptomatic with normal performance and there was not any evidence of local progression or distant metastasis.

Unusual cause of neuropathy: extensive dural spread of primary cervical osteosarcoma

We report a very rare case of a high grade osteosarcoma of the cervical spine in a 62-year-old woman. She presented with a relatively short history of a swelling in the posterior neck and cervical lymphadenopathy. This was associated with hoarseness of the voice, significant weight loss, and right upper arm radicular symptoms initially, progressing to paraplegia. Based on MR and CT imaging of the neck and an excision biopsy of an enlarged right supraclavicular lymph node, the histology revealed a high grade primary osteosarcoma of the cervical spine.

Follow-up of treated osteosarcoma patient

Objective

To evaluate the value of post-treatment follow-up in osteosarcoma patients.

Methods

Data were collected through a clinical record, with socio-demographic and clinical data, and information relating to the medical appointment. Descriptive analysis of the data was carried out. The Chi-squared test was used to associate the independent variables with attendance at scheduled follow-up appointments.

Results

We found a recurrence in 59.6% of cases, of which 58% were lung related; 44% presented clinical complaints and arrived on the scheduled date of the appointment. There was no statistically significant association between the demographic characteristics and early attendance of follow-up visits. 81.3% of the cases who came for the appointment earlier than originally scheduled presented complaints compared to those who did not (p=0.005). Of the cases who presented recurrence, 12.9% attended an appointment late and those who did not present recurrence, 47.6% were late for the appointment (p=0.006).

Conclusion

It is seen that the patients who came for an earlier appointment presented more complaints and were associated with the positive result of the exams carried out. The patients who had recurrence and came for an earlier appointment did not present a statistically significant difference in recurrence-free survival. It was observed that distance was not a predominant factor in late attendance at appointments. Level of Evidence II, Retrospective Study.

C-kit expression in human osteosarcoma and in vitro assays

Biologic agents targeting oncogenes have encourage researchs trying to correlate the role of tyrosine kinase in the pathogenesis of tumours. Osteosarcoma is a high grade aggressive neoplasm with poor survival. Our aim was to investigate c-kit immunoexpression, its prognostic relevance for patients with osteosarcoma, and the effect of imatinib mesylate (STI571) on proliferation and invasion of the human osteosarcoma cell line.A retrospective immunohistochemical study was performed on archival formalin-fixed paraffin-embedded specimens from 52 patients with high-grade primary osteosarcoma of extremities treated at the Pediatric Oncology Institute (IOP, GRAAC) and archived in the Department of Pathology, Federal University of São Paulo. Only pre-chemotherapy specimens were analyzed. Strongly stained cytoplasm and membrane cells were taken as positive. Human osteosarcoma cells from line MG-63 were incubated and the inhibitory effect of imatinib mesylate (STI571) on cell proliferation and invasion was studied. In 24 cases (46.15%), c-kit was expressed by the cells and c-kit-positive tumors exhibited lower necrosis post-chemotherapy. No correlation was found between c-kit expression and overall and disease-free survival. Imatinib mesylate decreased the rates of cell growth of osteosarcoma cells in low doses and invasion in high doses C-kit-positive tumors had worse response to chemotherapy and imatinib mesylate can play a role in blocking or decreasing the rate of growth of osteosarcoma cells, but not the invasive capacity of these neoplastic cells. These data suggested that imatinib mesylate could be a therapeutic target of strategies against osteosarcoma tumors. Further studies are necessary to confirm this indication.

Cutaneous extraskeletal osteosarcoma on the scar of a previous bone graft

Extraskeletal osteosarcoma (ESOS) is a very rare malignant tumor of mesenchymal origin. It is rarer than osseous osteosarcoma and there are very few reports of the skin being a primary site. Most reported cutaneous ESOS were accompanied with metastasis in other organs. A 56-year-old man presented with a painful, 1.5×0.8 cm sized, brown-colored nodule on the right girdle area for 3 months. The histologic findings revealed a tumor that was confined to the dermis without connection to the subcutaneous tissue. In addition, there were large amounts of thin and lace-like bony trabeculae and osteoid with neoplastic cells in a highly pleomorphic sarcomatous stroma.

Spontaneous osteosarcoma of the femur in a non-obese diabetic mouse

An abnormal swelling was identified in the distal portion of the right femur in a 1-year-old non-obese diabetic (NOD) mouse. Grossly, a large mass of the distal femur was observed in the right femur. Lesions were poorly marginated, associated with destruction of the cancellous and cortical elements of the bone, and showed ossification within the soft tissue component. Histologically, the tumor was identified as a poorly differentiated sarcoma. Histopathologic examination of the bone masses revealed invasive proliferation of poorly differentiated neoplastic mesenchymal cells forming streams, bundles, and nests, which resulted in destruction of normal bone. Neoplastic cells exhibited random variation in cellular appearance and arrangement, as well as matrix composition and abundance. Haphazard and often intermingling patterns of osteogenic, chondroblastic, lipoblastic, and angiogenic tissues were present. Larger areas of neoplastic bone and hyaline cartilage contained multiple large areas of hemorrhage and necrosis bordered by neoplastic cells. The mass was diagnosed as an osteosarcoma. To our knowledge, this is the first spontaneous osteosarcoma in an NOD mouse.