Chemotherapy, en bloc resection, and prosthetic bone replacement in the treatment of osteogenic sarcoma

Dynamic Prediction of Overall Survival for Patients with Osteosarcoma: A Retrospective Analysis of the EURAMOS-1 Clinical Trial Data

Current prediction models for patients with ostosarcoma are restricted to predictions from a single, static point in time, such as diagnosis or surgery. These approaches discard information which becomes available during follow-up and may have an impact on patient's prognosis. This study aims at developing a dynamic prediction model providing 5-year overall survival (OS) predictions from different time points during follow-up. The developed model considers relevant baseline prognostic factors, accounting for where appropriate time-varying effects and time-varying intermediate events such as local recurrence (LR) and new metastatic disease (NM). A landmarking approach is applied to 1965 patients with high-grade resectable osteosarcoma from the EURAMOS-1 trial (NCT00143030). Results show that LR and NM negatively affected 5-year OS (HRs: 2.634, 95% CI 1.845-3.761; 8.558, 95% CI 7.367-9.942, respectively). Baseline factors with strong prognostic value (HRs > 2) included poor histological response (≥10% viable tumor), axial tumor location, and the presence of lung metastases. The effect of poor versus good histological response changed over time, becoming non-significant from 3.25 years post-surgery onwards. This time-varying effect, as well as the strong impact of disease-related time-varying variables, show the importance of including updated information collected during follow-up in the model to provide more accurate survival predictions.

A dynamic microRNA profile that tracks a chemotherapy resistance phenotype in osteosarcoma. Implications for novel therapeutics

Osteosarcoma is a rare primary bone tumor for which no significant therapeutic advancement has been made since the late 1980s despite ongoing efforts. Overall, the five-year survival rate remains about 65%, and is much lower in patients with tumors unresponsive to methotrexate, doxorubicin, and cisplatin therapy. Genetic studies have not revealed actionable drug targets, but our group, and others, have reported that epigenomic biomarkers, including regulatory RNAs, may be useful prognostic tools for osteosarcoma. We tested if microRNA (miRNA) transcriptional patterns mark the transition from a chemotherapy sensitive to resistant tumor phenotype. Small RNA sequencing was performed using 14 patient matched pre-chemotherapy biopsy and post-chemotherapy resection high-grade osteosarcoma frozen tumor samples. Independently, small RNA sequencing was performed using 14 patient matched biopsy and resection samples from untreated tumors. Separately, miRNA specific Illumina DASL arrays were used to assay an independent cohort of 65 pre-chemotherapy biopsy and 26 patient matched post-chemotherapy resection formalin fixed paraffin embedded (FFPE) tumor samples. mRNA specific Illumina DASL arrays were used to profile 37 pre-chemotherapy biopsy and five post-chemotherapy resection FFPE samples, all of which were also used for Illumina DASL miRNA profiling. The National Cancer Institute Therapeutically Applicable Research to Generate Effective Treatments dataset, including PCR based miRNA profiling and RNA-seq data for 86 and 93 pre-chemotherapy tumor samples, respectively, was also used. Paired differential expression testing revealed a profile of 17 miRNAs with significantly different transcriptional levels following chemotherapy. Genes targeted by the miRNAs were differentially expressed following chemotherapy, suggesting the miRNAs may regulate transcriptional networks. Finally, an in vitro pharmacogenomic screen using miRNAs and their target transcripts predicted response to a set of candidate small molecule therapeutics which potentially reverse the chemotherapy resistance phenotype and synergize with chemotherapy in otherwise treatment resistant tumors. Importantly, these novel therapeutic targets are distinct from targets identified by a similar pharmacogenomic analysis of previously published prognostic miRNA profiles from pre chemotherapy biopsy specimens.

Extended distal femur resection: Megaprosthesis with telescopic bone allograft augmentation versus total femur prosthesis

BACKGROUND AND OBJECTIVE

Oncological distal femur resections can leave a proximal femur too short to host a stem. Reconstructive techniques are then challenging. The purpose of the study is to compare implant survival, complication rate and MSTS of two different options.

METHODS

We retrospectively divided 33 patients with primary bone tumours of distal femur in Group 1 (16 patients reconstructed with knee megaprosthesis with proximal bone augmentation, APC) and Group 2 (17 patients reconstructed with total femur prosthesis, TFP). Less than 12 cm of remaining proximal femur were planned for all resections.

RESULTS

MSTS score at 2 years is 25 ± 5 for Group 1 and 19 ± 7 for Group 2 (confidence interval [C.I.] 95%, p = 0.02). At 5 years it is 27 ± 2 for Group 1 and 22 ± 6 for Group 2 (C.I. 95%, p = 0.047). Failure and complication rates are lower for Group 1, but no statistical significance was reached. In APC reconstruction, union at the host-allograft junction was achieved in 16 out of 16 patients using the telescopic bone augmentation technique.

CONCLUSIONS

APC provides higher functional results compared to TFP after extended distal femur resection. In APC reconstruction, telescopic augmentation is excellent for achieving union at the host-allograft junction.

A Bibliometric Analysis of the 500 Most Cited Papers in Orthopaedic Oncology

BACKGROUND

Despite notable progress over time, broad insight into the scientific landscape of orthopaedic oncology is lacking. We conducted a bibliometric analysis of the 500 most cited papers in the field.

METHODS

We searched the Science Citation Index Expanded database of the Web of Science Core Collection to find the 500 most cited articles in the field.

RESULTS

Citation count ranged from 81 to 1,808. Articles were published from 1965 to 2018. Over half of all articles were published in the United States (53.6%). The 2000s was the most productive decade with 170 (34%) articles. All articles were written in English and were published across 29 journals. Female participation as first authors significantly increased from the 1960s to the 2010s (0% vs 14.6%, P = 0.0434). Similarly, female involvement as senior authors grew from the 1960s to the 2010s (0% vs 12.2%, P = 0.0607). Primary bone sarcomas were the most cited topic among articles from the 1970s to the 1980s. From studies produced in the 1990s up until the 2010s, reconstruction procedures were the most cited topic.

CONCLUSION

Trends over the years have resulted in an emphasis on a surgical technique. Notable progress has been made regarding gender diversity, yet disparities still exist.

ITGB3 promotes cisplatin resistance in osteosarcoma tumors

OBJECTIVE

Osteosarcoma is the most malignant and common primary bone tumor with a high rate of recurrence that mainly occurs in children and young adults. Therefore, it is vital to facilitate the development of novel effective therapeutic means and improve the overall prognosis of osteosarcoma patients via a deeper understanding of the mechanisms of chemoresistance in osteosarcoma progression.

METHODS

In this research, the relationship between ITGB3 and the clinical characteristics of patients was detected through analysis of publicly available clinical datasets. The expression of ITGB3 was analysis in collected human osteosarcoma tissues. In addition, the potential functions of ITGB3 in the cisplatin resistance of osteosarcoma cells were investigated in vitro and in tumor xenotransplantation. Finally, the molecular mechanism of ITGB3 in the progression and recurrence of osteosarcoma were explored via transcriptome analysis.

RESULTS

ITGB3 was identified as a potential regulator of tumorigenicity and cisplatin resistance in relapsed osteosarcoma. Furthermore, the decreased osteosarcoma cell proliferation and migration ability in ITGB3 knockout osteosarcoma cells were related to increased apoptosis and slowing cell cycle progression. In addition, ITGB3 had a positive correlation with cisplatin resistance in cells and tumor xenografts in mice. Accordingly, ITGB3 performed the functions of proliferation and cisplatin resistance in osteosarcoma through the MAPK and VEGF signaling pathways.

CONCLUSION

Our results will contribute to a better understanding of the function and mechanism of ITGB3 in osteosarcoma cisplatin resistance and provide a novel therapeutic target to decrease cisplatin resistance and tumor recurrence in osteosarcoma patients.

Accumulation of blood chromium and cobalt in the participants with metal objects: findings from the 2015 to 2018 National Health and Nutrition Examination Survey (NHANES)

BACKGROUND

Chromium (Cr) and cobalt (Co) are the essential elements for producing metal implants, but might have potential health issues. The research on the correlation between metal implants and blood Cr and Co on a large population is still limited.

METHODS

National Health and Nutrition Examination Survey (NHANES) is a program of studies designed to assess the health status of Americans began in the early 1960s. The study was based on the NHANES database from two data collection years (2015-2016 and 2017-2018). The exposure variable of this study was whether the participants had metal objects in the body or not. The outcome variables were blood concentrations of Cr and Co. Age, body mass index, sex, race/ethnicity, income to poverty ratio, tap water behavior, shellfish/fish/tuna/salmon eating habits, level of education, smoking behavior, marital status, blood hemoglobin, and data collection years were included as confounding variables.

RESULTS

A total of 4412 participants, aged 40 years or older, were included in this analysis, consisting of the without metal objects group (n = 3150) and the metal objects group (n = 1262). Metal objects was positively correlated to the accumulation of blood Cr (β = 0.072, 95% CI: 0.043-0.102, p < 0.001) and blood Co (β = 0.079, 95% CI: 0.049-0.109, p < 0.001). However, the positive correlation of metal objects with blood Cr was only presented in women (β = 0.112, 95% CI: 0.074-0.151, p < 0.001), but not in men. Meanwhile, the positive relationship between metal objects and blood Cr/Co was not observed in the Asian subgroup.

CONCLUSIONS

Blood Cr and Co concentrations were statistically higher in people with metal objects, but with race and sex differences.

LEVEL OF EVIDENCE

Level IV, cross-sectional study.

Osteosarcoma

Osteosarcoma is the most common primary malignant tumour of the bone. Osteosarcoma incidence is bimodal, peaking at 18 and 60 years of age, and is slightly more common in males. The key pathophysiological mechanism involves several possible genetic drivers of disease linked to bone formation, causing malignant progression and metastasis. While there have been significant improvements in the outcome of patients with localized disease, with event-free survival outcomes exceeding 60%, in patients with metastatic disease, event-free survival outcomes remain poor at less than 30%. The suspicion of osteosarcoma based on radiographs still requires pathological evaluation of a bone biopsy specimen for definitive diagnosis and CT imaging of the chest should be performed to identify lung nodules. So far, population-based screening and surveillance strategies have not been implemented due to the rarity of osteosarcoma and the lack of reliable markers. Current screening focuses only on groups at high risk such as patients with genetic cancer predisposition syndromes. Management of osteosarcoma requires a multidisciplinary team of paediatric and medical oncologists, orthopaedic and general surgeons, pathologists, radiologists and specialist nurses. Survivors of osteosarcoma require specialized medical follow-up, as curative treatment consisting of chemotherapy and surgery has long-term adverse effects, which also affect the quality of life of patients. The development of osteosarcoma model systems and related research as well as the evaluation of new treatment approaches are ongoing to improve disease outcomes, especially for patients with metastases.

Disease progression in osteosarcoma: a multistate model for the EURAMOS-1 (European and American Osteosarcoma Study) randomised clinical trial

OBJECTIVES

Investigating the effect of prognostic factors in a multistate framework on survival in a large population of patients with osteosarcoma. Of interest is how prognostic factors affect different disease stages after surgery, with stages of local recurrence (LR), new metastatic disease (NM), LR+NM, secondary malignancy, a second NM, and death.

DESIGN

An open-label, international, phase 3 randomised controlled trial.

SETTING

325 sites in 17 countries.

PARTICIPANTS

The subset of 1631 metastases-free patients from 1965 patients with high-grade resectable osteosarcoma, from the European and American Osteosarcoma Study.

MAIN OUTCOME MEASURES

The effect of prognostic factors on different disease stages, expressed as HRs; predictions of disease progression on an individual patient basis, according to patient-specific characteristics and history of intermediate events.

RESULTS

Of 1631 patients, 526 experienced an intermediate event, and 305 died by the end of follow-up. An axial tumour site substantially increased the risk of LR after surgery (HR=10.84, 95% CI 8.46 to 13.86) and death after LR (HR=11.54, 95% CI 6.11 to 21.8). A poor histological increased the risk of NM (HR=5.81, 95% CI 5.31 to 6.36), which sharply declined after 3 years since surgery. Young patients (<12 years) had a lower intermediate event risk (eg, for LR: HR=0.66, 95% CI 0.51 to 0.86), when compared with adolescents (12-18 years), but had an increased risk of subsequent death, while patients aged >18 had a decreased risk of death after event (eg, for death after LR: HR=2.40, 95% CI 1.52 to 3.90; HR=0.35, 95% CI 0.21 to 0.56, respectively).

CONCLUSIONS

Our findings suggest that patients with axial tumours should be monitored for LR and patients with poor histological response for NM, and that for young patients (<12) with an LR additional treatment options should be investigated.

TRIAL REGISTRATION NUMBER

NCT00134030.

Pediatric Osteosarcoma: Pearls and Pitfalls

Osteosarcoma is a malignant bone tumor most commonly presenting in children. It has a bimodal distribution with a peak incidence occurring during the ages of 10-14 years old and in adults greater than age 65. The first peak of osteosarcoma correlates with the increased proliferation of bone during the pubertal growth period. Osteosarcoma most frequently presents with localized bone pain, swelling, and an antalgic gait. The patient may attribute symptoms to trauma or strenuous exercise, causing the patient to be managed conservatively. In these cases, the pain persists and eventually leads to further evaluation. The most common type of osteosarcoma is the conventional high-grade osteosarcoma. For conventional osteosarcoma, the diagnosis is typically made or strongly suggested based upon the initial radiographic appearance. Other types of osteosarcomas include low grade central, telangiectatic, small-cell, surface and intracortical. Consequently, it is important for radiologists to be aware of these subtypes and the imaging features that differentiate them from other etiologies to prevent a delay in treatment.

Growth arrest-specific 5 lncRNA as a valuable biomarker of chemoresistance in osteosarcoma

Osteosarcoma is the most common primary malignant bone tumour in children and teenagers, and it is characterised by drug resistance and high metastatic potential. Increasing studies have highlighted the critical roles of long noncoding RNAs (lncRNAs) as oncogenes or tumour suppressors as well as new biomarkers and therapeutic targets in osteosarcoma. The growth arrestspecific 5 (GAS5) lncRNA can function as a tumour suppressor in several cancers. The present study aimed to validate GAS5 and other chemoresistanceassociated lncRNAs as biomarkers in a cohort of primary osteosarcoma samples, to obtain predictive information on resistance or sensitivity to treatment. The GAS5 and a panel of lncRNAs related to chemoresistance [SNGH1, FOXD2-AS1, deleted in lymphocytic leukemia (DLEU2) and LINC00963] were evaluated in a cohort of osteosarcoma patients enrolled at the Careggi University Hospital. Total RNA was extracted from formalin-fixed paraffin-embedded (FFPE) tissue sections and the expression levels of the lncRNAs were quantified by qPCR. A bioinformatic analysis on deposited RNA-seq data was performed to validate the qPCR results. Clustering analysis shows that GAS5 could be linked to the expression of isoforms 02 and 04 of the lncRNA DLEU2, whereas the DLEU2 isoform 08 is linked to the lncRNA LINC00963. We found that GAS5 is significantly increased in patients with a good prognosis and is expressed differently between chemosensitive and chemoresistant osteosarcoma patients. However, the results obtained are not concordant with the in-silico analysis performed on the TARGET osteosarcoma dataset. In the future, we would enlarge the case series, including different disease settings.

Shape-memory balloon offering simultaneous thermo/chemotherapies to improve anti-osteosarcoma efficacy

This paper proposes a shape-memory balloon (SMB) to improve bone cement injection efficiency and postoperative thermo/chemotherapy for bone tumors. The SMB consists of biodegradable poly(ε-caprolactone) (PCL), an anticancer drug (doxorubicin, DOX), and heat-generating magnetic nanoparticles (MNPs). The balloon shape is fabricated in a mold by crosslinking PCL macromonomers with DOX and MNPs. The mechanical properties and shape-transition temperature (approximately 40 °C) of the SMB are modulated by adjusting the molecular weight of PCL and the crosslinking density. This allows safe inflation at the affected site with a 400% expansion rate by simple blow molding. The expanded shape is temporarily memorized at 37 °C, and the computed tomography image shows that the bone cement is successfully injected without extra pressure or leakage. The SMB releases DOX for over 4 weeks, allowing a prolonged effect at the local site. The local dosing is constant as the medication is continuously released, demonstrating an ON-OFF switchable heating/cooling response to alternating magnetic field irradiation. In vitro cytotoxic studies have demonstrated that heat generation/drug release and only drug release from the balloon kill approximately 99% and 60% of human osteosarcoma cells, respectively. The proposed SMB is promising in postoperative local thermo/chemotherapy for bone tumors.

Development of a Nomogram for Predicting the Efficacy of Preoperative Chemotherapy in Osteosarcoma

Background

Due to the obvious heterogeneity of osteosarcoma, many patients are not sensitive to neoadjuvant chemotherapy. In this study, the clinical characteristics and auxiliary examinations of patients with osteosarcoma were used to predict the effect of preoperative chemotherapy, so as to guide the clinical adjustment of the treatment plan to improve the prognosis of patients.

Methods

In this study, 90 patients with pathologically confirmed osteosarcoma were included, and they were randomly divided into training cohort (n=45) and validation cohort (n=45). A prediction model of preoperative chemotherapy efficacy for osteosarcoma was established by multivariate logistic regression analysis, and a nomogram was used as the visualization of the model. The ROC curve and C-index were used to evaluate the accuracy of the nomogram. Decision curve analysis (DCA) was used to evaluate the net benefit of the nomogram in predicting the efficacy of neoadjuvant chemotherapy under different threshold probabilities.

Results

In the study, the age, gender, location, tumor volume, metastasis at the first visit, MSTS staging, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) were used in the multivariate logistic regression analysis and the construction of the nomogram. The AUC and C-index of the training cohort were 0.793 (95% CI: 0.632, 0.954) and 0.881 (95% CI: 0.776, 0.986), respectively. The AUC and C-index in the validation cohort were 0.791 (95% CI: 0.644, 0.938) and 0.813 (95% CI: 0.679, 0.947), respectively, which were close to the training cohort. DCA showed that the model had good clinical application value.

Conclusion

Based on the clinical characteristics of patients and auxiliary examinations, the nomogram can be good used to predict the efficacy of preoperative chemotherapy for osteosarcoma.

Distal femoral replacement - Cemented or cementless? Current concepts and review of the literature

Distal femoral endoprosthetic replacement has been successfully used to reconstruct distal femoral defects after tumor resection for over four decades. Despite continued advances, aseptic loosening continues to be the most common failure mode after infection. Debate still exists about a variety of design features and the optimal fixation method remains controversial. To date, no large-scale study or meta-analysis has demonstrated the superiority of one fixation technique over another. While the classic dichotomy of cemented versus cementless stems is well-known, the contemporary surgeon needs to fully understand the optimal clinical setting for each type of fixation technique and additional strategies to maximize implant stability. In clinical practice, the choice of fixation must be tailored to the individual patient. The surgeon must consider whether the operation is being performed for primary sarcoma or metastatic carcinoma, the presence of distant metastases, age, comorbidities, and whether radiotherapy has been previously given or will be required at the site of fixation. The best strategy for each patient optimizes tumor control and appropriately weighs risks of fixation failure versus the expected patient survival. This review will explore cemented and uncemented distal femoral replacement and highlight modern concepts to optimize each technique.

Update on Osteosarcoma

PURPOSE OF REVIEW

Osteosarcoma (OSA) is the most common primary tumor of bone, mainly affecting children and adolescents. Here we discuss recent advances in surgical and systemic therapies, and highlight potentially new modalities in preclinical evaluation and prognostication.

RECENT FINDINGS

The advent of neoadjuvant and adjuvant chemotherapy has markedly improved the disease-free recurrence and overall survival of OSA. However, treatment efficacy has been stagnant since the 1980s. This plateau has prompted preclinical and clinical research into in precision surgery, inhaled chemotherapy to increase pulmonary drug concentration without systemic side effects, and novel immunomodulators intended to block molecular pathways associated with OSA proliferation and metastasis. With the advent of novel surgical techniques and new forms and vectors for chemotherapy, it is hoped that OSA treatment outcomes will exceed their currently sustained plateau in the near future.

Willingness of patients with sarcoma to participate in cancer surveillance research: a cross-sectional patient survey

OBJECTIVES

To determine the proportion of patients with extremity sarcoma who would be willing to participate in a clinical trial in which they would be randomised to one of four different postoperative sarcoma surveillance regimens. Additionally, we assessed patients' perspectives on the burden of cancer care, factors that influence comfort with randomisation and the importance of cancer research.

DESIGN

Prospective, cross-sectional patient survey.

SETTING

Outpatient sarcoma clinics in Canada, the USA and Spain between May 2017 and April 2020. Survey data were entered into a study-specific database.

PARTICIPANTS

Patients with extremity sarcoma who had completed definitive treatment from seven clinics across Canada, the USA and Spain.

MAIN OUTCOME MEASURES

The proportion of patients with extremity sarcoma who would be willing to participate in a randomised controlled trial (RCT) that evaluates varying postoperative cancer surveillance regimens.

RESULTS

One hundred thirty complete surveys were obtained. Respondents reported a wide range of burdens related to clinical care and surveillance. The majority of patients (85.5%) responded that they would agree to participate in a cancer surveillance RCT if eligible. The most common reason to participate was that they wanted to help future patients. Those that would decline to participate most commonly reported that participating in research would be too much of a burden for them at a time when they are already feeling overwhelmed. However, most patients agreed that cancer research will help doctors better understand and treat cancer.

CONCLUSIONS

These results demonstrate that most participants would be willing to participate in an RCT that evaluates varying postoperative cancer surveillance regimens. Participants' motivation for trial participation included altruistic reasons to help future patients and deterrents to trial participation included the overwhelming burden of a cancer diagnosis. These results will help inform the development of patient-centred RCT protocols in sarcoma surveillance research.

LEVEL OF EVIDENCE

V.

Recent Insights into Therapy Resistance in Osteosarcoma

Osteosarcoma, the most common bone malignancy of childhood, has been a challenge to treat and cure. Standard chemotherapy regimens work well for many patients, but there remain minimal options for patients with progressive or resistant disease, as clinical trials over recent decades have failed to significantly improve survival. A better understanding of therapy resistance is necessary to improve current treatments and design new strategies for future treatment options. In this review, we discuss known mechanisms and recent scientific advancements regarding osteosarcoma and its patterns of resistance against chemotherapy, radiation, and other newly-introduced therapeutics.

The YAP/TEAD Axis as a New Therapeutic Target in Osteosarcoma: Effect of Verteporfin and CA3 on Primary Tumor Growth

Although some studies suggested that disruption of the Hippo signaling pathway is associated with osteosarcoma progression, the molecular mechanisms by which YAP regulates primary tumor growth is not fully clarified. In addition, the validation of YAP as a therapeutic target through the use of inhibitors in a preclinical model must be demonstrated. RNA-seq analysis and Kaplan-Meier assays identified a YAP signature in osteosarcoma patients and a correlation with patients' outcomes. Molecular and cellular analysis (RNAseq, PLA, immunoprecipitation, promoter/specific gene, proliferation, cell cycle assays) using overexpression of mutated forms of YAP able or unable to interact with TEAD, indicate that TEAD is crucial for YAP-driven cell proliferation and in vivo tumor growth. In addition, in vivo experiments using an orthotopic mice model of osteosarcoma show that two YAP/TEAD inhibitors, verteporfin and CA3, reduce primary tumor growth. In this context, in vitro experiments demonstrate that these inhibitors decrease YAP expression, YAP/TEAD transcriptional activity and cell viability mainly by their ability to induce cell apoptosis. We thus demonstrate that the YAP/TEAD signaling axis is a central actor in mediating primary tumor growth of osteosarcoma, and that the use of YAP inhibitors may be a promising therapeutic strategy against osteosarcoma tumor growth.

Sarcoma treatment in the era of molecular medicine

Sarcomas are heterogeneous and clinically challenging soft tissue and bone cancers. Although constituting only 1% of all human malignancies, sarcomas represent the second most common type of solid tumors in children and adolescents and comprise an important group of secondary malignancies. More than 100 histological subtypes have been characterized to date, and many more are being discovered due to molecular profiling. Owing to their mostly aggressive biological behavior, relative rarity, and occurrence at virtually every anatomical site, many sarcoma subtypes are in particular difficult-to-treat categories. Current multimodal treatment concepts combine surgery, polychemotherapy (with/without local hyperthermia), irradiation, immunotherapy, and/or targeted therapeutics. Recent scientific advancements have enabled a more precise molecular characterization of sarcoma subtypes and revealed novel therapeutic targets and prognostic/predictive biomarkers. This review aims at providing a comprehensive overview of the latest advances in the molecular biology of sarcomas and their effects on clinical oncology; it is meant for a broad readership ranging from novices to experts in the field of sarcoma.

A systematic review of radiomics in osteosarcoma: utilizing radiomics quality score as a tool promoting clinical translation

OBJECTIVES

To assess the methodological quality and risk of bias in radiomics studies investigating diagnosis, therapy response, and survival of patients with osteosarcoma.

METHODS

In this systematic review, literatures on radiomics in osteosarcoma were included and assessed for methodological quality through the radiomics quality score (RQS). The risk of bias and concern of application was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool. A meta-analysis of studies focusing on predicting osteosarcoma response to neoadjuvant chemotherapy was performed.

RESULTS

Twelve radiomics studies exploring osteosarcoma were identified, and five were included in meta-analysis. The RQS reached an average of 20.4% (6.92 of 36) with good inter-rater agreement (ICC 0.95, 95% CI 0.85-0.99). Four studies validated results with an internal dataset, none of which used external dataset; one study was prospectively designed, and another one shared part of the dataset. The risk of bias and concern of application were mainly related to index test aspect. The meta-analysis showed a diagnostic odds ratio of 43.68 (95%CI 13.5-141.31) for predicting response to neoadjuvant chemotherapy with high heterogeneity and low methodological quality.

CONCLUSIONS

The overall scientific quality of included studies is insufficient; however, radiomics remains a promising technology for predicting treatment response, which might guide therapeutic decision-making and related to prognosis. Improvements in study design, validation, and open science needs to be made to demonstrate the generalizability of findings and to achieve clinical applications. Widespread application of RQS, pre-trained RQS scoring procedure, and modification of RQS in response to clinical needs are necessary.

KEY POINTS

• Limited radiomics studies were established in osteosarcoma with mean RQS of 20.4%, commonly due to unvalidated results, retrospective study design, and absence of open science. • Meta-analysis of radiomics studies predicting osteosarcoma response to neoadjuvant chemotherapy showed high diagnostic odds ratio 43.68, while high heterogeneity and low methodological quality were the main concerns. • A previously trained data extraction instrument allowed reaching moderate inter-rater agreement in RQS applications, while RQS still needs improvement to become a wide adaptive tool in reviews of radiomics studies, in routine self-check before manuscript submitting and in study design.

Treatment of malignant bone tumor: limb salvage surgery using metallic tumor prosthesis

Recently, most bone cancers have shown a dismal prognosis even though they were managed with amputation. In the 1970s, anticancer drugs began to be used for bone tumor treatment as adjuvant agents, with the hope of survival improvement, while keeping the limb preserved. The 5-year survival of osteosarcoma patients increased up to 70% with anticancer chemotherapy and limb-salvage surgery. Limb salvage surgery includes all surgical procedures performed to accomplish resection of a malignant bone tumor and reconstruction of the skeletal system with an acceptable oncological and functional outcome. Currently, surgeons can choose a variety of reconstruction methods, including osteoarticular allograft, allograft-prosthesis composite, and metallic tumor endoprosthesis. However, complication rates are still high. The advancement of implant technology, adjuvant chemotherapy, and radiologic imaging modality has contributed to the evolution of limb salvage surgery. Nevertheless, there are still many barriers that have yet to be addressed to move further.

Guideline for Limb-Salvage Treatment of Osteosarcoma

Osteosarcoma is the most common primary malignant bone tumor, occurring mainly in children and adolescents, and the limbs are the main affected sites. At present, limb‐salvage treatment is considered as an effective basic standard treatment for osteosarcoma of the limb. China has a vast territory, but the development of technology is not balanced,which requires sufficient theoretical coverage, strong technical guidance and the application of limb‐salvage treatment guidelines to the treatment of osteosarcoma. Therefore, to standardize and promote the development of limb‐salvage surgery technology and improve the success rate of limb‐salvage treatment, this guide systematically introduces limb‐salvage techniques for the treatment of patients with limb osteosarcoma through definition of limb‐salvage treatment, surgical methods, efficacy evaluation, postoperative treatment and prevention of complications, rehabilitation guidance, and follow‐up advice.

TH1579, MTH1 inhibitor, delays tumour growth and inhibits metastases development in osteosarcoma model

Background

Osteosarcoma (OS) is the most common primary malignant bone tumour. Unfortunately, no new treatments are approved and over the last 30 years the survival rate remains only 30% at 5 years for poor responders justifying an urgent need of new therapies. The Mutt homolog 1 (MTH1) enzyme prevents incorporation of oxidized nucleotides into DNA and recently developed MTH1 inhibitors may offer therapeutic potential as MTH1 is overexpressed in various cancers.

Methods

The aim of this study was to evaluate the therapeutic benefits of targeting MTH1 with two chemical inhibitors, TH588 and TH1579 on human osteosarcoma cells. Preclinical efficacy of TH1579 was assessed in human osteosarcoma xenograft model on tumour growth and development of pulmonary metastases.

Findings

MTH1 is overexpressed in OS patients and tumour cell lines, compared to mesenchymal stem cells. In vitro, chemical inhibition of MTH1 by TH588 and TH1579 decreases OS cells viability, impairs their cell cycle and increases apoptosis in OS cells. TH1579 was confirmed to bind MTH1 by CETSA in OS model. Moreover, 90 mg/kg of TH1579 reduces in vivo tumour growth by 80.5% compared to non-treated group at day 48. This result was associated with the increase in 8-oxo-dG integration into tumour cells DNA and the increase of apoptosis. Additionally, TH1579 also reduces the number of pulmonary metastases.

Interpretation

All these results strongly provide a pre-clinical proof-of-principle that TH1579 could be a therapeutic option for patients with osteosarcoma.

Funding

This study was supported by La Ligue Contre le Cancer, la SFCE and Enfants Cancers Santé.

Adjuvant and Neoadjuvant Chemotherapy for Osteosarcoma: A Historical Perspective

Osteosarcoma was initially resistant to chemotherapy that worked for Ewing sarcoma and rhabdomyosarcoma as well as other chemotherapeutic agents available in the 1960s. In the early 1970s, responses of osteosarcoma to adriamycin were reported, and at about the same time, so were responses of osteosarcoma to high-dose methotrexate. These agents were introduced into adjuvant therapy due to the dire prognosis associated with apparently localized osteosarcoma. After initial questions regarding the role of chemotherapy delayed its uniform acceptance, there is now general agreement that chemotherapy is primarily responsible for the cure of patients with osteosarcoma when combined with surgical elimination of the primary tumor. Advances with combination chemotherapy later adding cisplatin and ifosfamide have improved ultimate survival. The history of the development of effective chemotherapy combinations at Memorial Sloan Kettering Cancer Center, UT MD Anderson Cancer Center, and the Rizzoli Institute are highlighted, and recent large cooperative group studies are reviewed in the context of those findings.

Reconstructive Science in Orthopedic Oncology

Limb salvage is widely practiced as standard of care in most cases of extremity bone sarcoma. Allograft and endoprosthesis reconstructions are the most widely utilized modalities for the reconstruction of large segment defects, however complication rates remain high. Aseptic loosening and infection remain the most common modes of failure. Implant integration, soft-tissue function, and infection prevention are crucial for implant longevity and function. Macro and micro alterations in implant design are reviewed in this manuscript. Tissue engineering principles using nanoparticles, cell-based, and biological augments have been utilized to develop implant coatings that improve osseointegration and decrease infection. Similar techniques have been used to improve the interaction between soft tissues and implants. Tissue engineered constructs (TEC) used in combination with, or in place of, traditional reconstructive techniques may represent the next major advancement in orthopaedic oncology reconstructive science, although preclinical results have yet to achieve durable translation to the bedside.

HSP90AA1-mediated autophagy promotes drug resistance in osteosarcoma

Background

Osteosarcoma is the most common primary bone tumor in children and adolescents. Unfortunately, osteosarcoma treatments often fail due to the development of chemoresistance, of which the underlying molecular mechanisms still remain unclear. In this study, we demonstrated that HSP90AA1 gene is responsible for drug resistance in osteosarcoma through an autophagy-related mechanism.

Methods

shRNAs were transfected into osteosarcoma cells for knockdown of HSP90AA1 gene. Stable HSP90AA1 overexpressing osteosarcoma cell lines were obtained by lentivirus infection. mRNA and protein expressions of HSP90AA1 in osteosarcoma cells were tested by quantitative real-time PCR and western blot, respectively. Autophagy of osteosarcoma cells was detected by western blot of LC3, transmission electron microscopy and fluorescence microscope. mRFP-GFP-LC3 lentiviral transfection was also performed to detect autophagic flux. NOD/SCID mices were inoculated with MG-63 tumor cells transfected with HSP90AA1 specific shRNA. TUNEL and LC3 staining were performed to detect apoptosis and autophagy of resected tumor tissues.

Results

Doxorubicin, cisplatin, and methotrexate, which are commonly used in chemotherapy, each induced HSP90AA1 upregulation in human osteosarcoma cells. Suppression of HSP90AA1 restored the sensitivity of osteosarcoma cells to chemotherapy both in vivo and in vitro. Mechanism study indicated that autophagy is responsible for the chemoresistance in osteosarcoma cells. HSP90AA1 increased drug resistance by inducing autophagy and inhibiting apoptosis. Suppression of HSP90AA1 diminished autophagic protection in response to chemotherapy in osteosarcoma cells. Moreover, HSP90AA1 promotes autophagy through PI3K/Akt/mTOR pathway and inhibits apoptosis through JNK/P38 pathway.

Conclusion

We showed that chemotherapy agents can induce HSP90AA1 expression in osteosarcoma cells. And HSP90AA1, acting as an important regulator of autophagy, is a critical factor in the development of osteosarcoma chemoresistance both in vitro and in vivo. HSP90AA1 provides a novel therapeutic target for improving osteosarcoma treatment.

Electronic supplementary material

The online version of this article (10.1186/s13046-018-0880-6) contains supplementary material, which is available to authorized users.

More severe toxicity of genetic polymorphisms on MTHFR activity in osteosarcoma patients treated with high-dose methotrexate

5,10-Methylenetrahydrofolate reductase (MTHFR), a key enzyme for folate metabolism, catalyses the irreversible conversion of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, which is located at the end of the short arm (1p36.3). Two common non-synonymous variants, the C677T (Ala222Val) and A1298C (Glu429Ala), were mainly described with decreased enzymatic activity and an alteration of intracellular folate distribution. Osteosarcomas are currently treated with high dose of methotrexate (MTX). The decreased enzyme activity of MTHFR theoretically could increase the drug action of MTX and at the same time increase toxic and side effect. Germline variants of C677T and A1298C were studied in 59 osteosarcoma patients, with whom the A1298C is detected with particularly low rate of mutant genotype (N = 1, 0.8%) and could not proceed with statistical calculations. 15 patients were wild type of C677T (CC, 25.4%), 20 were heterozygous mutant genotype (CT, 33.9%) and 24 were homozygous mutant genotype (TT, 40.7%). Patients harboring the TT/CT genotype had the same progression-free survival and tumor necrosis rate in comparison with patients having the CC genotype (P = 0.349 and P = 0.465 respectively). And the C677T polymorphisms had no significant correlation with MTX initial plasma concentration (P = 0.867; r = 0.024) and delayed elimination (P = 0.305; r = −0.136). However patients with mutant genotype of C677T were associated with higher degree of liver toxicity (P = 0.043) and fever reaction of MTX (P = 0.050) while G3/G4 hematologic toxicity were more likely to be noticed with TT than CT/CC (P = 0.095). The study suggests that genetic polymorphism of MTHFR C677T in the MTX metabolic pathway seems to be associated with the trend for more side effects statistically, but has no obvious effect on histologic response and survival.

Osteosarcoma, Chondrosarcoma, and Chordoma

Osteosarcoma (OS), chondrosarcoma, and chordoma are characterized by multiple challenges to the investigator, clinician, and patient. One consequence of their rarity among sarcomas, as well as their biologic and clinical heterogeneity, is that management guidelines are inadequate to inform the range of individual patient-treatment decisions from diagnosis, approaches to surgery, chemotherapy, radiotherapy, treatment of recurrence, palliative care, and quality of survivorship. Of high-grade sarcomas, OSs are among the most curable, with more than two-thirds of patients with localized disease likely to achieve long-term survival. Neoadjuvant chemotherapy comprising cisplatin, doxorubicin, and methotrexate with intercalated surgery is the standard of care for resectable OS in those younger than 40 years. Outcomes for OS presenting with unresectable metastases or recurrent disease, or in those older than 40 years are generally poor. Overall results have improved little for all patients with OS, and new treatments are needed. Surgical resection remains the cornerstone of management for chondrosarcoma and chordoma. However, the application of new biologic insights to therapeutic development indicates that improved treatments may soon be routine for patients with chondrosarcoma and chordoma for whom surgery alone is inadequate. For all these uncommon diseases, patients should be offered specialist expert care delivered by experienced multidisciplinary teams in high-volume centers.

The prognostic value of PCNA expression in patients with osteosarcoma: A meta-analysis of 16 studies

BACKGROUND

Numerous studies have attempted to determine the prognostic role of proliferating cell nuclear antigen (PCNA) expression in patients with osteosarcoma with no consistent conclusion. We performed this meta-analysis to systematically elucidate the association in a more precise manner.The purpose of this meta-analysis is to determine the prognostic role of PCNA in patients with osteosarcoma.

METHODS

A systematic search of relevant studies was performed in 6 electronic databases including PubMed, Embase, Web of Science, Wanfang database, China National Knowledge Internet (CNKI) database, and Chinese Biological Medical (CBM) Database (up to March 1, 2016) with the following keywords: (PCNA OR proliferating cell nuclear antigen) AND (osteosarcoma OR osteogenic tumor). A manual search of references on relevant articles was also conducted by 2 investigators independently. We performed a comprehensive evaluation of the correlation between PCNA expression and overall survival (OS) or disease-free survival (DFS) by calculating relative ratios (RR) and their corresponding 95% confidence intervals (CI) using STATA software. A fixed- or random-effect model was chosen based on the between-study heterogeneity.

RESULTS

In total, 16 studies with 691 osteosarcoma patients were included in this meta-analysis. PCNA overexpression was found in approximately 57.31% of the patients with osteosarcoma. The meta-analysis suggested that PCNA overexpression in osteosarcoma patients is associated with low OS, but not significantly with DFS (RR = 1.82, 95% CI 1.53-2.18, P = .000; RR = 1.15, 95% CI 0.91-1.44, P = 0.234). Sensitivity analysis for OS and DFS showed no significant difference and the pooled RRs were stable when the included studies were removed one by one. Similar results were also obtained for subgroup analysis based on different follow-ups and cutoffs to determine PCNA expression.

CONCLUSION

The findings from this meta-analysis indicate that PCNA overexpression is an effective biomarker for poor prognosis in patients with osteosarcoma for OS. Hence, more large-scale studies are still needed to further warrant this conclusion.

Tumor histopathological response to neoadjuvant chemotherapy in childhood solid malignancies: is it still impressive?

The management of oncological malignancies has significantly improved over the last decades. In modern medicine, new concepts and trends have emerged paving the way for the era of personalized and evidence-based strategies adapted to the patients’ prognostic variables and requirements. Several challenges do exist that are encountered during the management, including the difficulty to assess chemotherapy response with certainty. Having known that neoadjuvant chemotherapy might be the only solution for a proportion of patients with tumors that are unresectable at diagnosis, emergence of strategies that use risk group-directed therapy became an integral part in the management of oncological malignancies. Tumor histopathological change post neoadjuvant chemotherapy is one of the most important predictors of management outcome and is being used in many chemotherapy protocols as an essential determinant of the most suitable postoperative chemotherapy regimen. Bone tumors are the classic models of this approach; however, other childhood solid tumors show significant variations in outcome as a result of tumor histopathological response to neoadjuvant chemotherapy. The aim of this review is therefore to summarize the significance of histopathological responses seen after neoadjuvant chemotherapy in childhood solid tumors. Moreover, it suggests that the effect on tumor histopathology through modifying neoadjuvant chemotherapy and, on the other hand, toxicities from intensifying adjuvant chemotherapy might either necessitate the change of a number of arm groups in different protocol regimens or include newer chemotherapeutic agents adjuvantly for better outcome and lesser toxicities in poor tumor histopathological responders.

Management of Bone Sarcoma

Treatment of bone sarcoma requires careful planning and involvement of an experienced multidisciplinary team. Significant advancements in systemic therapy, radiation, and surgery in recent years have contributed to improved functional and survival outcomes for patients with these difficult tumors, and emerging technologies hold promise for further advancement.

Saurolactam Inhibits Proliferation, Migration, and Invasion of Human Osteosarcoma Cells

Osteosarcoma is a common type of malignant bone tumor with features of osteoid formation or osteolytic lesions of bone. New therapeutic approaches are urgently needed since it lacks response to chemotherapeutic treatments. Saurolactam, a natural compound isolated from the aerial portions of Saururus chinensis, was reported to have an anti-inflammatory activity. Here, we demonstrate that saurolactam shows anti-cancer activity against human osteosarcoma cells. Saurolactam treatment inhibited proliferation of human osteosarcoma cell lines MG-63 and HOS and decreased colony formation in soft agar in a dose-dependent manner. Intraperitoneal administration of saurolactam at 25 mg/kg of body weight for 21 days dramatically inhibited the growth of MG-63 xenografts in nude mice. Flow cytometric analysis indicated that saurolactam treatment (20 μM) led to G1 cell cycle arrest and induced apoptosis in these two cell lines. Western analysis suggested that saurolactam treatment resulted in a reduction of Akt/PKB, phospho-Ser473-Akt, c-Myc, and S-phase kinase-associated protein 2 (Skp2) in MG-63 and HOS osteosarcoma cells. Akt overexpression significantly abolished saurolactam-induced decrease in protein and phosphorylation levels of Akt, c-Myc, and Skp2 protein levels, implying that Akt inactivation was a causal mediator of saurolactam-induced inhibition of c-Myc and Skp2. Moreover, Skp2 overexpression in MG-63 cells partly abolished the growth inhibition induced by saurolactam. Saurolactam treatment repressed migration and invasion ability, and Skp2 overexpression significantly blocked these inhibitory effects of saurolactam in MG-63 Cells. The present study indicates that saurolactam might represent a new promising agent to improve osteosarcoma treatment.

Pediatric Osteosarcoma: An Updated Review

Osteosarcoma (OS), the most common type of primary malignant bone tumor, is defined by the presence of malignant mesenchymal cells producing osteoid or immature bone. The peak incidence of the most frequent type of OS, i.e., high-grade central OS, occurs in the second decade of life during the adolescent growth spurt. Most patients suffer from the pain and swelling in the involved region and, usually, seek medical attention. Diagnosis is carried out by conventional radiographs, computed tomography, and magnetic resonance image (MRI). In addition, three-phase bone scans, thallium scintigraphy, dynamic MRI, and positron emission spectroscopy are new innovative promising tools. OS can be treated with surgery, radiotherapy, and chemotherapy. There is a clear need for newer effective agents for patients with OS, especially for patients who afflicted with metastatic and recurrence tumor. Monoclonal antibodies directed against OS may prove useful as treatment, either for drug delivery or for radiopharmaceuticals.

Effect of Unplanned Therapy on the Prognosis of Patients with Extremity Osteosarcoma

Unplanned therapy for extremity osteosarcoma can result in erroneous surgical procedures and lack of neoadjuvant chemotherapy before the first operation. Our aim was to compare the prognosis between patients with extremity osteosarcoma who received unplanned therapy and those who received standard treatment. This was a retrospective review of patients with extremity osteosarcoma who received appropriate surgical treatment and neoadjuvant chemotherapy (n = 79) and those who received unplanned therapy (n = 24) between June 2000 and October 2014. Survival rate, local recurrence rate and metastasis rate were compared between the two groups. We found that patients who had unplanned therapy had a higher local recurrence rate (41.7% vs. 21.5%; P = 0.049) and a shorter mean time for recurrence (8.90 vs. 14.59 months; P = 0.018). There was no significant difference between groups in the 5-year survival rate (56.3% vs.67.8%; P = 0.356), metastasis rate (45.8% vs. 30.4%; P = 0.125) and mean time to metastasis (23.18 vs.18.24 months; P = 0.396). Our findings suggest that unplanned therapy for extremity osteosarcoma can result in failure of local control. The use of supplementary interventions after unplanned therapy, such as neoadjuvant chemotherapy and limb salvage surgery, may explain the similar survival and metastasis rates between patients receiving unplanned therapy and those receiving standard treatment.

Noscapine targets EGFRp-Tyr1068 to suppress the proliferation and invasion of MG63 cells

Osteosarcoma, the most common primary malignant bone tumor, usually arises in the metaphysis of long bones. Amplification and mutation of the epidermal growth factor receptor (EGFR) gene represent signature genetic abnormalities encountered in osteosarcoma. Noscapine is a benzylisoquinoline alkaloid derived from the opium poppy Papaver somniferum. Recently several studies have suggested its anti-cancer effect in melanoma, ovarian cancer, gliomas, breast cancer, lung cancer, and colon cancer. However, the underlying molecular mechanism for its anti-cancer effect still remains unclear. In this paper, we found the mechanism of noscapine effectively suppressed proliferation and invasion of MG63 cell line by inhibiting the phosphorylation of EGFR and its downstream pathway.

A note from history: Landmarks in history of cancer, part 7

In the 2 and half decades reviewed (1970-1995), research established that chromosomal translocation, deletion, and DNA amplification are prerequisites to cancerogenesis and that oncogenes, tumor-suppressor genes, growth factors, and cytokines play crucial roles in the pathomechanism of cancer. Human papillomavirus, human immunodeficiency virus, herpes virus, and hepatitis B virus were identified as cancer-causing viruses. Several laboratory tests were developed for the detection of primary and recurrent cancers, and cancer prevention by screening methods was popularized. Sonography, computerized tomography, magnetic resonance imaging, positron emission tomography, excision of sentinel lymph nodes, and immunohistochemical techniques became routine procedures. Clinicopathologic staging and classification of tumors were standardized. Limited surgery, adjuvant and neoadjuvant chemoradiation, and the therapeutic use of monoclonal antibodies, tumor vaccines, and targeted chemotherapy became routine practice. The decline in cancer incidence and mortality demonstrated that cancer prevention and advancement in oncology are pivotal to success in the crusade against cancer. Above all, it was clearly established that the care of patients with cancer can be accomplished best in a multidisciplinary setting involving surgical oncologists, radiologists, radiation therapists, medical oncologists, surgical pathologists, and laboratory scientists. In conclusion, the 25 years from 1970 and 1995 are the high-water mark in clinical oncology, and this is the period when oncology turned from art to science.

Correlation between the expression of vegf and survival in osteosarcoma

Objective:

To present a series of 50 consecutive patients with non-metastatic extremity osteosarcoma, and attempt to correlate expression of the vascular endothelial growth factor (VEGF) protein in biopsy tissue to their prognosis regarding overall survival, disease-free survival and local recurrence.

Methods:

Fifty cases of non-metastatic osteosarcoma of the extremities treated between 1986 and 2006 at Instituto de Ortopedia e Traumatologia da Universidade de São Paulo, São Paulo, Brasil, were evaluated regarding expression of the VEGF protein. There were 19 females and 31 males. The mean age was 16 years old (range 5-28 years old) and the mean follow-up was 60.6 months (range 25-167 months). The variables studied were age, gender, anatomic location, type of surgery, surgical margins, tumor size, post chemotherapy necrosis, local recurrence, pulmonary metastasis and death.

Results:

Thirty-six patients showed VEGF expression on 30% or less cells (low), and the remaining 14 cases had VEGF expression above 30% (high). Among the 36 patients with low VEGF expression, nine developed pulmonary metastasis and four died (11.1%). Among the 14 patients with high VEGF expression, six developed pulmonary metastasis and three died (21.4%).

Conclusion:

There was no statistically significant correlation between the expression of VEGF and any of the variables studied. Level of Evidence IV, Therapeutic Study.

EURAMOS-1, an international randomised study for osteosarcoma: results from pre-randomisation treatment

BACKGROUND

Four international study groups undertook a large study in resectable osteosarcoma, which included two randomised controlled trials, to determine the effect on survival of changing post-operative chemotherapy based on histological response.

PATIENTS AND METHODS

Patients with resectable osteosarcoma aged ≤40 years were treated with the MAP regimen, comprising pre-operatively of two 5-week cycles of cisplatin 120 mg/m(2), doxorubicin 75 mg/m(2), methotrexate 12 g/m(2) × 2 (MAP) and post-operatively two further cycles of MAP and two cycles of just MA. Patients were randomised after surgery. Those with ≥10% viable tumour in the resected specimen received MAP or MAP with ifosfamide and etoposide. Those with <10% viable tumour were allocated to MAP or MAP followed by pegylated interferon. Longitudinal evaluation of quality of life was undertaken.

RESULTS

Recruitment was completed to the largest osteosarcoma study to date in 75 months. Commencing March 2005, 2260 patients were registered from 326 centres across 17 countries. About 1334 of 2260 registered patients (59%) were randomised. Pre-operative chemotherapy was completed according to protocol in 94%. Grade 3-4 neutropenia affected 83% of cycles and 59% were complicated by infection. There were three (0.13%) deaths related to pre-operative chemotherapy. At definitive surgery, 50% of patients had at least 90% necrosis in the resected specimen.

CONCLUSIONS

New models of collaboration are required to successfully conduct trials to improve outcomes of patients with rare cancers; EURAMOS-1 demonstrates achievability. Considerable regulatory, financial and operational challenges must be overcome to develop similar studies in the future. The trial is registered as NCT00134030 and ISRCTN 67613327.

A novel androstenedione derivative induces ROS-mediated autophagy and attenuates drug resistance in osteosarcoma by inhibiting macrophage migration inhibitory factor (MIF)

Osteosarcoma is a common primary bone tumor in children and adolescents. The drug resistance of osteosarcoma leads to high lethality. Macrophage migration inhibitory factor (MIF) is an inflammation-related cytokine implicated in the chemoresistance of breast cancer. In this study, we isolated a novel androstenedione derivative identified as 3,4-dihydroxy-9,10-secoandrosta-1,3,5,7-tetraene-9,17-dione (DSTD). DSTD could inhibit MIF expression in MG-63 and U2OS cells. The inhibition of MIF by DSTD promoted autophagy by inducing Bcl-2 downregulation and the translocation of HMGB1. N-acetyl-L-cysteine (NAC) and 3-methyladenine (3-MA) attenuated DSTD-induced autophagy but promoted cell death, suggesting that DSTD induced ROS-mediated autophagy to rescue cell death. However, in the presence of chemotherapy drugs, DSTD enhanced the chemosensitivity by decreasing the HMGB1 level. Our data suggest MIF inhibition as a therapeutic strategy for overcoming drug resistance in osteosarcoma.

[Chemotherapeutic concepts for bone sarcomas]

BACKGROUND

Osteosarcoma and Ewing sarcoma are the most common chemosensitive sarcomas of the bone.

AIM

Development in chemotherapeutic concepts as well as current and future treatment strategies in osteosarcoma and Ewing sarcoma are presented.

METHODS

A PubMed search for "Osteosarcoma" and "Ewing sarcoma" was performed, and pertinent results were summarized.

RESULTS

In both osteosarcoma and Ewing sarcoma, outcomes achieved with multimodal treatment concepts combining conventional chemotherapy and local treatment have reached a plateau of about 70% for 5-year survival rates.

DISCUSSION

Improved insights into the molecular biology and genetics of the diseases as well as insights into the interactions between sarcoma cells and the micro-environment and the immune system are necessary to identify novel therapeutic targets in bone sarcomas. Because of the rarity of the diseases, multinational cooperation is essential to evaluate novel therapies in prospective randomized trials.

The association of glutathione S-transferase polymorphisms in patients with osteosarcoma: evidence from a meta-analysis

Osteosarcoma is a life-threatening malignancy that often occurs in teenagers. Numerous studies have reported glutathione S-transferase polymorphisms are associated with osteosarcoma, but the results are inconclusive, partially because the sample size in each of published studies is relatively small. Therefore, we performed a meta-analysis of the published studies to estimate the association more accurately. To preciously examine the association between the glutathione S-transferase polymorphisms and osteosarcoma, we undertook a meta-analysis of six case-control studies. The association between the glutathione S-transferase polymorphisms and osteosarcoma risk was assessed by odds ratios together with their 95% confidence intervals using a fixed-effects model or random-effects model. In addition, hazard ratio was used to measure the relationship between glutathione S-transferase polymorphisms and prognosis in patients with osteosarcoma. We found that there was significant association between the polymorphisms in GSTT1 or GSTM3 (AA versus BB) and osteosarcoma risk. In addition, there is no evidence of association on GSTM1, GSTT1, GSTP1 (IIe/IIe versus IIe/Val) or GSTP1 (IIe/IIe versus Val/Val) polymorphisms with prognosis in osteosarcoma. In conclusion, the GSTT1 and GSTM3 polymorphisms might influence osteosarcoma risk.

Imatinib mesylate exerts anti-proliferative effects on osteosarcoma cells and inhibits the tumour growth in immunocompetent murine models

Osteosarcoma is the most common primary malignant bone tumour characterized by osteoid production and/or osteolytic lesions of bone. A lack of response to chemotherapeutic treatments shows the importance of exploring new therapeutic methods. Imatinib mesylate (Gleevec, Novartis Pharma), a tyrosine kinase inhibitor, was originally developed for the treatment of chronic myeloid leukemia. Several studies revealed that imatinib mesylate inhibits osteoclast differentiation through the M-CSFR pathway and activates osteoblast differentiation through PDGFR pathway, two key cells involved in the vicious cycle controlling the tumour development. The present study investigated the in vitro effects of imatinib mesylate on the proliferation, apoptosis, cell cycle, and migration ability of five osteosarcoma cell lines (human: MG-63, HOS; rat: OSRGA; mice: MOS-J, POS-1). Imatinib mesylate was also assessed as a curative and preventive treatment in two syngenic osteosarcoma models: MOS-J (mixed osteoblastic/osteolytic osteosarcoma) and POS-1 (undifferentiated osteosarcoma). Imatinib mesylate exhibited a dose-dependent anti-proliferative effect in all cell lines studied. The drug induced a G0/G1 cell cycle arrest in most cell lines, except for POS-1 and HOS cells that were blocked in the S phase. In addition, imatinib mesylate induced cell death and strongly inhibited osteosarcoma cell migration. In the MOS-J osteosarcoma model, oral administration of imatinib mesylate significantly inhibited the tumour development in both preventive and curative approaches. A phospho-receptor tyrosine kinase array kit revealed that PDGFRα, among 7 other receptors (PDFGFRβ, Axl, RYK, EGFR, EphA2 and 10, IGF1R), appears as one of the main molecular targets for imatinib mesylate. In the light of the present study and the literature, it would be particularly interesting to revisit therapeutic evaluation of imatinib mesylate in osteosarcoma according to the tyrosine-kinase receptor status of patients.

Recent advances in the management of osteosarcoma and forthcoming therapeutic strategies

Osteosarcoma is the most frequent primary bone tumor and occurs mainly in young patients (average age: 18 years). No evolution of the survival rates has been recorded for two decades in response to current treatment, associating often toxic and badly tolerated cures of chemotherapy (given a significant rate of bad responders) with preserving surgery. Among the proposed innovative strategies, immune-based therapy, antiangiogenesis agents, tumor-suppressor or suicide gene therapy, or anticancer drugs not commonly used in osteosarcoma are presented. A further strategy is to target the tumor microenvironment rather than the tumor itself.