Adjuvant and neoadjuvant combination chemotherapy for osteogenic sarcoma

Discovery of potent thiazolidin-4-one sulfone derivatives for inhibition of proliferation of osteosarcoma in vitro and in vivo

Chemotherapy combining with surgical treatment has been the main strategy for osteosarcoma treatment in clinical. Due to unclear pathogenesis and unidentified drug targets, significant progress has not been made in the development of targeted drugs for osteosarcoma during the past 50 years. Our previous discovery reported compound R-8i with a high potency for the treatment of osteosarcoma by phenotypic screening. However, both the metabolic stability and bioavailability of R-8i are poor (T1/2 = 5.36 min, mouse liver microsome; and bioavailability in vivo F = 52.1 %, intraperitoneal administration) which limits it use for further drug development. Here, we described an extensive structure-activity relationship study of thiazolidine-4-one sulfone inhibitors from R-8i, which led to the discovery of compound 68. Compound 68 had a potent cellular activity with an IC50 value of 0.217 μM, much higher half-life (T1/2 = 73.8 min, mouse liver microsome) and an excellent pharmacokinetic profile (in vivo bioavailability F = 115 %, intraperitoneal administration). Compound 68 also showed good antitumor effects and low toxicity in a xenograft model (44.6 % inhibition osteosarcoma growth in BALB/c mice). These results suggest that compound 68 is a potential drug candidate for the treatment of osteosarcoma.

A Natural Organic Compound "Decursin" Has Both Antitumor and Renal Protective Effects: Treatment for Osteosarcoma

Osteosarcoma is a rare malignant tumor that commonly occurs in children. Anticancer drugs, for example, cisplatin, aid in postsurgery recovery but induce side effects such as renal damage, affecting the life prognosis of patients. Decursin which is one of the bioactive components has been reported for its anti-inflammatory, antioxidant, and antitumor effects, but the effect on osteosarcoma is unexplained. In this study, the research theme was to examine the sensitizing effect of decursin and its influence on cisplatin-induced nephrotoxicity. The cell viability and half maximal inhibitory concentration (IC50), apoptosis induction, and effect on cell cycle and Akt pathways were examined. In vivo, we examine the effects of decursin on tumors and mice bodies. Additionally, the effects of the cisplatin-decursin combination were evaluated in vitro and in vivo. Decursin suppressed cell viability and induced apoptosis via the cell cycle. Decursin also inhibited the Akt pathway by suppressing the phosphorylation of Akt. It enhanced apoptosis induction and lowered cell viability in combination with cisplatin. The increasing tumor volume was suppressed in the decursin-administrated group with further suppression in combination with cisplatin compared to sole cisplatin administration. The decrease in renal function and renal epithelial cell damage caused by cisplatin was improved by the combinatorial treatment with decursin. Therefore, decursin demonstrated an antitumor effect on the osteosarcoma cells and a renal protective effect in combination with cisplatin. Therefore, decursin is a prospective therapeutic agent against osteosarcoma.

Ewing's sarcoma of proximal femur: case report of extreme osteotomy with 3D-printed prosthesis for the reconstruction

Background: Resection and reconstruction of malignant bone tumors at the proximal femur in adolescent patients has remained a clinical challenge. Considering the growth and development requirements of adolescents, there is no unified standard for the reconstruction of bone defects at the proximal femur. Here, we report a case of 3D-printed titanium alloy customized prosthesis for the construction of proximal femoral bone defects in an adolescent patient with Ewing's sarcoma of the proximal femur. Case presentation: A 7-year-old female patient presented to a local hospital with left hip pain, and was diagnosed with Ewing's sarcoma on the proximal left femur. The patient received two courses of neoadjuvant chemotherapy before surgery according to the standard protocol. Considering growth and development problems associated with adolescents, we adopted a customized 3D-printed prosthesis of proximal femur for preservation of the femoral head and part of the femoral neck in the affected limb. Clinical outcomes, recorded after 12 months of follow-up, revealed excellent functional recovery and satisfactory functional scores of the affected limb, with no immediate complications. Conclusion: 3D-printed prosthesis is a feasible method for preserving femoral head and reconstruction of bone defects in adolescents' proximal femur.

Functional role of MicroRNA/PI3K/AKT axis in osteosarcoma

Osteosarcoma (OS) is a primary malignant bone tumor that occurs in children and adolescents, and the PI3K/AKT pathway is overactivated in most OS patients. MicroRNAs (miRNAs) are highly conserved endogenous non-protein-coding RNAs that can regulate gene expression by repressing mRNA translation or degrading mRNA. MiRNAs are enriched in the PI3K/AKT pathway, and aberrant PI3K/AKT pathway activation is involved in the development of osteosarcoma. There is increasing evidence that miRNAs can regulate the biological functions of cells by regulating the PI3K/AKT pathway. MiRNA/PI3K/AKT axis can regulate the expression of osteosarcoma-related genes and then regulate cancer progression. MiRNA expression associated with PI3K/AKT pathway is also clearly associated with many clinical features. In addition, PI3K/AKT pathway-associated miRNAs are potential biomarkers for osteosarcoma diagnosis, treatment and prognostic assessment. This article reviews recent research advances on the role and clinical application of PI3K/AKT pathway and miRNA/PI3K/AKT axis in the development of osteosarcoma.

Incidence, survival, and associated factors estimation in osteosarcoma patients with lung metastasis: a single-center experience of 11 years in Tianjin, China

BACKGROUND

Osteosarcoma is the most common primary malignant bone tumor. The current study was conducted to describe the general condition of patients with primary osteosarcoma in a single cancer center in Tianjin, China and to investigate the associated factors in osteosarcoma patients with lung metastasis.

METHODS

From February 2009 to October 2020, patients from Tianjin Medical University Cancer Institute and Hospital, China were retrospectively analyzed. The Kaplan-Meier method was used to evaluate the overall survival of osteosarcoma patients. The Cox proportional hazard regression analysis was performed to analyze the prognostic factors of all osteosarcoma patients and those patients with lung metastasis, respectively. Furthermore, risk factors for developing lung metastasis were identified in synchronous lung metastasis (SLM) and metachronous lung metastasis (MLM) patients.

RESULTS

A total of 203 patients were involved and 150 patients were successfully followed up for survival status. The 5-year survival rate of osteosarcoma was 70.0% and the survival months for patients with SLM and MLM were 33.3 ± 12.6 and 45.8 ± 7.4 months, respectively. The presence of lung metastasis was one of the independent prognostic factors for prognosis of osteosarcoma. In patients with lung metastasis, twenty-one (10.3%) showed lung metastasis at the diagnosis of osteosarcoma and 67 (33%) were diagnosed with lung metastases during the later course. T3 stage (OR = 11.415, 95%CI 1.362-95.677, P = 0.025) and bone metastasis (OR = 6.437, 95%CI 1.69-24.51, P = 0.006) were risk factors of SLM occurrence. Bone metastasis (OR = 1.842, 95%CI 1.053-3.224, P = 0.032), good necrosis (≥ 90%, OR = 0.032, 95%CI 0.050-0.412, P < 0.001), elevated Ki-67 (OR = 2.958, 95%CI 1.098-7.969, P = 0.032) and elevated LDH (OR = 1.791, 95%CI 1.020-3.146, P = 0.043) were proved to be independent risk factors for developing MLM.

CONCLUSION

The overall survival, prognostic factors and risk factors for lung metastasis in this single center provided insight about osteosarcoma management.

Imatinib-Functionalized Galactose Hydrogels Loaded with Nanohydroxyapatite as a Drug Delivery System for Osteosarcoma: In Vitro Studies

This study reports an impact of structure (XRPD, FT-IR) and surface morphology (SEM-EDS) of imatinib-functionalized galactose hydrogels, loaded and unloaded with nHAp, on osteosarcoma cell (Saos-2 and U-2OS) viability, levels of free oxygen radicals, and nitric oxide, levels of BCL-2, p53, and caspase 3 and 9, as well as glycoprotein-P activity. It was investigated how the rough surface of the crystalline hydroxyapatite-modified hydrogel affected amorphous imatinib (IM) release. The imatinib drug effect on cell cultures has been demonstrated in different forms of administration-directly to the culture or the hydrogels. Administration of IM and hydrogel composites could be expected to reduce the risk of multidrug resistance development by inhibiting P_gp.

Association of circulating tumor cells and IMP3 expression with metastasis of osteosarcoma

Background

Circulating tumor cells (CTCs) have been identified as a prognostic biomarker of tumors such as breast cancer and nasopharyngeal carcinoma, because they are obtained through a simple and noninvasive blood draw or liquid biopsy, but its clinical significance in osteosarcoma is still unclear. In this study, we analyzed the relationship between CTCs and clinicopathological features and discussed whether CTCs could be used as a biomarker for metastasis in osteosarcoma.

Methods

We enrolled 50 osteosarcoma patients with Enneking Stage IIB and Stage III and detected CTCs in 5 ml of peripheral blood samples collected from patients using the Canpatrol^® CTC detection platform. Subsequently, multiplex RNA in situ hybridization (RNA-ISH) based on various molecular markers was performed to identify and classify CTCs. The relationships between clinical pathological features and CTC counts, subtypes (epithelial type, E type; hybrid epithelial/mesenchymal type, H type; mesenchymal type, M type), and insulin-like growth factor mRNA-binding protein 3 (IMP3) expression in CTCs were analyzed.

Results

CTCs were detected in 86% (43/50) of the osteosarcoma patients. The CTC counts, especially the total CTCs and H-type CTCs, signifcantly differed between Enneking Stage IIB and Stage III patients (P < 0.05). No significant differences were observed between the CTC count or type and other clinicopathological features (P > 0.05). There were significant differences in the expression of IMP3 in different types of CTCs, and the IMP3 positive rates in E/H/M type CTCs were 38.4, 65.6, and 62.0%, respectively (P < 0.001). Receiver operating characteristic (ROC) curve analysis showed that IMP3-positive CTC count had the best performance for diagnostic metastasis, with the largest area under the curve of 0.873 and cutoff value of four cells/5ml blood (sensitivity = 87.5%; specificity = 82.4%). Serial CTC monitoring in one patient suggested that total CTCs and H-type CTCs were associated with disease progression.

Conclusion

This study demonstrates that the CTCs, especially the IMP3-positive CTCs and H/M-type CTCs, are related to the metastasis of osteosarcoma.

Extracellular vesicles: A new diagnostic biomarker and targeted drug in osteosarcoma

Osteosarcoma (OS) is a primary bone cancer that is highly prevalent among adolescents and adults below the age of 20 years. The prognostic outcome of metastatic OS or relapse is extremely poor; thus, developing new diagnostic and therapeutic strategies for treating OS is necessary. Extracellular vesicles (EVs) ranging from 30–150 nm in diameter are commonly produced in different cells and are found in various types of body fluids. EVs are rich in biologically active components like proteins, lipids, and nucleic acids. They also strongly affect pathophysiological processes by modulating the intercellular signaling pathways and the exchange of biomolecules. Many studies have found that EVs influence the occurrence, development, and metastasis of osteosarcoma. The regulation of inflammatory communication pathways by EVs affects OS and other bone-related pathological conditions, such as osteoarthritis and rheumatoid arthritis. In this study, we reviewed the latest findings related to diagnosis, prognosis prediction, and the development of treatment strategies for OS from the perspective of EVs.

Construction and validation of a novel apoptosis-associated prognostic signature related to osteosarcoma metastasis and immune infiltration

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Osteosarcoma is one of the most aggressive diseases which often develops metastasis.

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Apoptosis relates to the recurrence and metastasis of osteosarcoma and the related signature could predict the prognosis of patients.

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A novel apoptosis-associated prognosis signature related to osteosarcoma metastasis and immune infiltration has been developed.

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The signature could help to predict the prognosis of osteosarcoma patients and serve as the potential targets for anti-cancer treatment.

Background

Apoptosis played vital roles in the formation and progression of osteosarcoma. However, no studies elucidated the prognostic relationships between apoptosis-associated genes (AAGs) and osteosarcoma.

Methods

The differentially expressed genes associated with osteosarcoma metastasis and apoptosis were identified from GEO and MSigDB databases. The apoptosis-associated prognostic signature was established through univariate and multivariate cox regression analyses. The Kaplan–Meier (KM) survival curve, ROC curve and nomogram were constructed to investigate the predictive value of this signature. CIBERSORT algorithm and ssGSEA were used to explore the relationships between immune infiltration and AAG signature. The above results were validated in another GEO dataset and the expression of AAGs was also validated in osteosarcoma patient samples by immunohistochemistry.

Results

HSPB1 and IER3 were involved in AAG signature. In training and validation datasets, apoptosis-associated risk scores were negatively related to patient survival rates and the AAG signature was regarded as the independent prognostic factor. ROC and calibration curves demonstrated the signature and nomogram were reliable. GSEA revealed the signature related to immune-associated pathways. ssGSEA indicated that one immune cell and three immune functions were significantly dysregulated. The immunohistochemistry analyses of patients’ samples revealed that AAGs were significantly differently expressed between metastasis and non-metastasis osteosarcomas.

Conclusions

The present study identified and validated a novel apoptosis-associated prognostic signature related to osteosarcoma metastasis. It could serve as the potential biomarker and therapeutic targets for osteosarcoma in the future.

Short-term clinical outcomes of Kyocera Modular Limb Salvage System designed cementless stems for the endoprosthetic reconstruction of lower extremities: a Japanese Musculoskeletal Oncology Group multi-institutional study

BACKGROUND

The high rate of aseptic loosening of cemented stems has led to their frequent use in endoprosthetic reconstruction. However, problems, such as stem breakage and stress shielding at the insertion site, remain. The Japanese Musculoskeletal Oncology Group (JMOG) has developed Kyocera Modular Limb Salvage System (KMLS) cementless stems with a unique tapered press-fit and short fixation design. This study aimed to clarify the short-term postoperative outcomes of this prosthesis and validate the stem design.

METHODS

One hundred cases of KMLS cementless stems (51 male patients; median age, 49 years; mean follow-up period, 35 months), with a minimum follow-up of 2 years, for the proximal femur (PF), distal femur (DF), and proximal tibia were prospectively registered for use. Prosthesis survival, complication rates, postoperative functional, and radiographical evaluation were analyzed. Complications or failures after insertion of the KMLS endoprostheses were classified into five types and functional results were analyzed according to the MSTS scoring system at postoperative 1 year. The diaphyseal interface and anchorage were graded by the ISOLS system at postoperative 2 years.

RESULTS

The overall prosthesis survival rates at 2 and 4 years were 88.2 and 79.6%, respectively. The prosthesis-specific survival rate excluding infection and tumor recurrence was 90.2 and 87.9%, respectively. Younger age (p = 0.045) and primary tumor (p = 0.057) were associated with poor prognosis of prosthesis-specific survival excluding infection and tumor recurrence. Complications were observed in 31 patients, 13 patients underwent revision surgery. The mean MSTS functional score at 1 year postoperatively was 68%. Early implant loosening was significantly more common in the DF (p = 0.006) and PF/DF straight stem (p = 0.038). The ISOLS radiographic evaluation at 2 years after surgery revealed good bone remodeling and anchorage in most cases (bone remodeling: 90% / excellent and good, anchorage: 97% / excellent and good).

CONCLUSIONS

Tumor endoprosthesis long-term fixation to the diaphysis of the lower extremity remains challenging. The KMLS cementless stem with a unique tapered press fit design showed good short-term results in maintaining bone stock. To prevent early loosening, a curved stem should be used in PF and DF, but long-term follow-up is necessary.

Natural-like Chalcones with Antitumor Activity on Human MG63 Osteosarcoma Cells

Osteosarcoma (OS) is a malignant disease characterized by poor prognosis due to a high incidence of metastasis and chemoresistance. Recently, Licochalcone A (Lic-A) has been reported as a promising agent against OS. Starting from chalcones selected from a wide in-house library, a new series was designed and synthetized. The antitumor activity of the compounds was tested on the MG63 OS cell line through the innovative Quantitative Phase Imaging technique and MTT assay. To further investigate the biological profile of active derivatives, cell cycle progression and apoptosis induction were evaluated. An earlier and more consistent arrest in the G2-M phase with respect to Lic-A was observed. Moreover, apoptosis was assessed by Annexin V staining as well as by the detection of typical morphological features of apoptotic cells. Among the selected compounds, 1e, 1q, and 1r proved to be the most promising antitumor molecules. This study pointed out that an integrated methodological approach may constitute a valuable platform for the rapid screening of large series of compounds.

An External-Validated Prediction Model to Predict Lung Metastasis among Osteosarcoma: A Multicenter Analysis Based on Machine Learning

Background

Lung metastasis greatly affects medical therapeutic strategies in osteosarcoma. This study aimed to develop and validate a clinical prediction model to predict the risk of lung metastasis among osteosarcoma patients based on machine learning (ML) algorithms.

Methods

We retrospectively collected osteosarcoma patients from the Surveillance Epidemiology and End Results (SEER) database and from four hospitals in China. Six ML algorithms, including logistic regression (LR), gradient boosting machine (GBM), extreme gradient boosting (XGBoost), random forest (RF), decision tree (DT), and multilayer perceptron (MLP), were applied to build predictive models for predicting lung metastasis using patient's demographics, clinical characteristics, and therapeutic variables from the SEER database. The model was internally validated using 10-fold cross-validation to calculate the mean area under the curve (AUC) and the model was externally validated using the Chinese multicenter osteosarcoma data. Relative importance ranking of predictors was plotted to understand the importance of each predictor in different ML algorithms. The correlation heat map of predictors was plotted to understand the correlation of each predictor, selecting the 10-fold cross-validation with the highest AUC value in the external validation ROC curve to build a web calculator.

Results

Of all enrolled patients from the SEER database, 17.73% (194/1094) developed lung metastasis. The multiple logistic regression analysis showed that sex, N stage, T stage, surgery, and bone metastasis were all independent risk factors for lung metastasis. In predicting lung metastasis, the mean AUCs of the six ML algorithms ranged from 0.711 to 0.738 in internal validation and 0.697 to 0.729 in external validation. Among the six ML algorithms, the extreme gradient boosting (XGBoost) model had the highest AUC value with an average internal AUC of 0.738 and an external AUC of 0.729. The best performing ML algorithm model was used to build a web calculator to facilitate clinicians to calculate the risk of lung metastasis for each patient.

Conclusions

The XGBoost model may have the best prediction effect and the online calculator based on this model can help doctors to determine the lung metastasis risk of osteosarcoma patients and help to make individualized medical strategies.

Phase 2 study for nonmetastatic extremity high-grade osteosarcoma in pediatric and adolescent and young adult patients with a risk-adapted strategy based on ABCB1/P-glycoprotein expression: An Italian Sarcoma Group trial (ISG/OS-2)

Background

According to retrospective osteosarcoma series, ABCB1/P‐glycoprotein (Pgp) overexpression predicts for poor outcomes. A prospective trial to assess a risk‐adapted treatment strategy using mifamurtide in Pgp+ patients was performed.

Methods

This was a phase 2, multicenter, uncontrolled trial including patients 40 years old or younger with nonmetastatic extremity high‐grade osteosarcoma stratified according to Pgp expression. All patients received high‐dose methotrexate, doxorubicin, and cisplatin (MAP) preoperatively. In Pgp+ patients, mifamurtide was added postoperatively and combined with MAP for a good histologic response (necrosis ≥ 90%; good responders [GRs]) or with high‐dose ifosfamide (HDIFO) at 3 g/m²/d on days 1 to 5 for a histologic response < 90% (poor responders [PRs]). Pgp– patients received MAP postoperatively. After an amendment, the cumulative dose of methotrexate was increased from 60 to 120 g/m² (from 5 to 10 courses). The primary end point was event‐free survival (EFS). A postamendment analysis was performed.

Results

In all, 279 patients were recruited, and 194 were included in the postamendment analysis: 70 (36%) were Pgp–, and 124 (64%) were Pgp+. The median follow‐up was 51 months. For Pgp+ patients, 5‐year EFS after definitive surgery (null hypothesis, 40%) was 69.8% (90% confidence interval [CI], 62.2%‐76.2%): 59.8% in PRs and 83.7% in GRs. For Pgp– patients, the 5‐year EFS rate was 66.4% (90% CI, 55.6%‐75.1%).

Conclusions

This study showed that adjuvant mifamurtide, combined with HDIFO for a poor response to induction chemotherapy, could improve EFS in Pgp+ patients. Overall, the outcomes compared favorably with previous series. Mifamurtide and HDIFO as salvage chemotherapy are worth further study.

The expression of ABCB1/P‐glycoprotein (Pgp) at diagnosis has been used to stratify patients with high‐grade osteosarcoma. Adjuvant mifamurtide, combined with high‐dose ifosfamide for a poor response to induction chemotherapy, can improve event‐free survival in Pgp+ patients.

Mechanistic Insights of Chelator Complexes with Essential Transition Metals: Antioxidant/Pro-Oxidant Activity and Applications in Medicine

The antioxidant/pro-oxidant activity of drugs and dietary molecules and their role in the maintenance of redox homeostasis, as well as the implications in health and different diseases, have not yet been fully evaluated. In particular, the redox activity and other interactions of drugs with essential redox metal ions, such as iron and copper, need further investigation. These metal ions are ubiquitous in human nutrition but also widely found in dietary supplements and appear to exert major effects on redox homeostasis in health, but also on many diseases of free radical pathology. In this context, the redox mechanistic insights of mainly three prototype groups of drugs, namely alpha-ketohydroxypyridines (alpha-hydroxypyridones), e.g., deferiprone, anthraquinones, e.g., doxorubicin and thiosemicarbazones, e.g., triapine and their metal complexes were examined; details of the mechanisms of their redox activity were reviewed, with emphasis on the biological implications and potential clinical applications, including anticancer activity. Furthermore, the redox properties of these three classes of chelators were compared to those of the iron chelating drugs and also to vitamin C, with an emphasis on their potential clinical interactions and future clinical application prospects in cancer, neurodegenerative and other diseases.

Novel 2-phenyl-3-(Pyridin-2-yl) thiazolidin-4-one derivatives as potent inhibitors for proliferation of osteosarcoma cells in vitro and in vivo

Due to unknown pathogenesis and unidentified drug target, no drug for the treatment of osteosarcoma (OS) has been launched to the market. Herein, thiazolidinone 1a was discovered as a hit compound by phenotypic screening with an in-house patrimonial collection of structural diversity. The following SAR (Structure-Activity Relationship) study affords the final water-soluble lead compound (R)-8i as a potential inhibitor for the proliferation of OS cells by the modulation of solubility of the compounds with remarkable cellular potency (IC₅₀ = 21.9 nM for MNNG/HOS cells) and in vivo efficacy (52.9% inhibition OS growth in mice), as well as pharmacokinetic properties. (R)-8i also significantly suppresses OS cell migration in vitro and showed to be well-tolerated. Our preliminary investigation shows that the effects of (R)-8i are not dependent on p53 and myoferlin (MYOF). These results suggest that (R)-8i might be a potential drug candidate for OS treatment.

Malignant Giant Cell Tumor of Bone With a KRAS G12V Mutation

Malignant giant cell tumor of bone (GCTB) is a rare, aggressive, sarcoma occurring in adolescent and young adults. It is characterized by the presence of multinucleated giant cells and an aggressive clinical course. Because of the rarity of this tumor, no standard therapies have been identified. Current treatment regimens often include osteosarcoma chemotherapy protocols. We present a case of a malignant GCTB with a KRAS G12V mutation. This mutation is a known oncogenic driver that has not previously been reported on patients with malignant GCTB.

A genome-wide expression profile of noncoding RNAs in human osteosarcoma cells as they acquire resistance to cisplatin

BACKGROUND

Recurrence after cisplatin therapy is one of the major hindrances in the management of cancer. This necessitates a deeper understanding of the molecular signatures marking the acquisition of resistance. We therefore modeled the response of osteosarcoma (OS) cells to the first-line chemotherapeutic drug cisplatin. A small population of nondividing cells survived acute cisplatin shock (persisters; OS-P). These cells regained proliferative potential over time re-instating the population again (extended persisters; OS-EP).

RESULT

In this study, we present the expression profile of noncoding RNAs in untreated OS cells (chemo-naive), OS-P, OS-EP and drug-resistant (OS-R) cells derived from the latter. RNA sequencing was carried out, and thereafter, differential expression (log2-fold ± 1.5; p value ≤ 0.05) of microRNAs (miRNAs) was analyzed in each set. The core set of miRNAs that were uniquely or differentially expressed in each group was identified. Interestingly, we observed that most of each group had their own distinctive set of miRNAs. The miRNAs showing an inverse correlation in expression pattern with mRNAs were further selected, and the key pathways regulated by them were delineated for each group. We observed that pathways such as TNF signaling, autophagy and mitophagy were implicated in multiple groups.

CONCLUSION

To the best of our knowledge, this is the first study that provides critical information on the variation in the expression pattern of ncRNAs in osteosarcoma cells and the pathways that they might tightly regulate as cells acquire resistance.

Oncological and Functional Outcomes in Joint-sparing Resections of the Proximal Femur for Malignant Primary Bone Tumors

BACKGROUND

Joint-sparing resections (JSR) of the proximal femur allow for preservation of the proximal femoral growth plate and native hip joint, but whether this offers fewer complications or better function and longevity of the reconstruction remains unknown. In this study, we compared the functional outcomes of pediatric patients with bone sarcomas undergoing JSR of the proximal femur with intercalary allograft (ICA) reconstruction to those undergoing proximal femoral resections (PFR) with allograft-prosthetic composite (APC) reconstructions.

METHODS

We retrospectively reviewed all patients undergoing JSR with ICA reconstruction and PFR with APC reconstructions between 1995 and 2013 at a tertiary pediatric referral center. Primary outcomes included major and minor complications and secondary outcomes included the need for a secondary procedure, presence of local or distant relapse, survival status, and the presence of pain and ambulatory status (limp, assistive device, highest level of function). We assessed differences in outcomes using the Fisher exact and Wilcoxon rank-sum tests.

RESULTS

Eight patients underwent a JSR and ICA reconstruction, while 7 patients underwent a PFR with APC reconstruction. Median patient follow-up was 60.4 months (interquartile range: 36.8 to 112.9) Patients undergoing JSR and ICA reconstruction were younger than patients undergoing PFR with APC reconstruction (7.7 vs. 11.7 y, P=0.043); however, we found no other statistically significant differences in patient demographics. There were no statistically significant differences in primary or secondary outcomes between the study groups; however, patients who underwent JSR with ICA had more major complications (62.5% vs. 42.9%, P=0.29) and a lower rate of minor complications (25% vs. 28.6%, P=0.22).

CONCLUSION

Treatment of proximal femoral bone sarcomas in pediatric and adolescent patients remains a challenging enterprise. JSR with ICA reconstruction in the proximal femur, when feasible, may provide a similar function and risk of intermediate-term major and minor complications when compared with PFR with APC reconstruction. Further long-term studies are required to determine the impact of the native femoral head retention with respect to revision rates.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Selected using bioinformatics and molecular docking analyses, PHA-793887 is effective against osteosarcoma

To identify novel prognostic and therapeutic targets for osteosarcoma patients, we compared the gene expression profiles of osteosarcoma and control tissues from the GSE42352 dataset in the Gene Expression Omnibus. Differentially expressed genes were subjected to Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, Gene Set Enrichment and protein-protein interaction network analyses. Survival curve analyses indicated that osteosarcoma patients with lower mRNA levels of cyclin-dependent kinase 1 (CDK1) and topoisomerase II alpha had better prognoses. Various computer-aided techniques were used to identify potential CDK1 inhibitors for osteosarcoma patients, and PHA-793887 was predicted to be a safe drug with a high binding affinity for CDK1. In vitro, MTT and colony formation assays demonstrated that PHA-793887 reduced the viability and clonogenicity of osteosarcoma cells, while a scratch assay suggested that PHA-793887 impaired the migration of these cells. Flow cytometry experiments revealed that PHA-793887 dose-dependently induced apoptosis in osteosarcoma cells. Western blotting and enzyme-linked immunosorbent assays indicated that CDK1 expression in osteosarcoma cells declined with increasing PHA-793887 concentrations. These results suggest that PHA-793887 could be a promising new treatment for osteosarcoma.

A New Proximal Femur Reconstruction Technique after Bone Tumor Resection in a Very Small Patient: An Exemplificative Case

For patients too young to be fitted with an expandable prosthesis, limb salvage surgery requires other strategies. The main problems are related to the impossibility of implanting an expandable prosthesis to the residual bone growth that is much too big in relation to the bone size, with the precocious implant loosening and/or the residual absence of bone growth, as well as the problem of limb length and shape difference. In this paper, we report a possible reconstruction solution using a composite prosthesis for an Ewing’s sarcoma of the proximal femur in an infant patient. After resection, a femoral stem was cemented into the distal third of a homoplastic humerus; a carbon fiber plate was used to stabilize the bone/homograft interface. At the one-year follow-up, the patient was free of disease and able to walk with only a slight limp. This case report describes a possible solution for very small patients. An adult humerus is of the right size to replace a child’s lower limb segments, and the distal humerus can be shaped, maintaining a cortex stiff enough to support a prosthesis. Very young patients might obtain a faster osteointegration of the graft than adults, due to their higher biological activity and, in this case, the diapasonal shape of the allograft might also have contributed to accelerated fusion. Moreover, the use of a graft to fit the prosthesis avoids loosening issues due to canal widening, hypothetically providing more growing time before system failure and revision surgery. However, although this technique is promising, further studies are necessary to confirm our findings and to verify if this procedure allows easier future prosthesis implantation.

Zoledronic Acid Enhanced the Antitumor Effect of Cisplatin on Orthotopic Osteosarcoma by ROS-PI3K/AKT Signaling and Attenuated Osteolysis

Osteoclasts can interact with osteosarcoma to promote the growth of osteosarcoma. Cisplatin is common in adjuvant chemotherapy of osteosarcoma. However, due to chemoresistance, the efficacy is profoundly limited. Previous studies have found that zoledronic acid (ZA) has osteoclast activation inhibition and antitumor effect. However, the combined effect of ZA and cisplatin on osteosarcoma remains unclear. In vitro, the effects of ZA and cisplatin alone or in combination on 143B cell activity, proliferation, apoptosis, and ROS-PI3K/AKT signaling were detected. At the same time, the effect of ZA and cisplatin on osteoclast formation, survival, and activity was detected by TRAP staining and bone plate absorption test. These were further verified in mice. The results showed that in vitro, compared with the single treatment and control, the combination of ZA and cisplatin could significantly inhibit the activity and proliferation of 143B cells and induced their apoptosis and further promoted the generation of ROS and inhibited the phosphorylation of PI3K and AKT. ROS scavenger and the agonist of the PI3K/AKT pathway could reverse these results. In addition, cisplatin in synergy with ZA could significantly inhibit osteoclast formation and survival to reduce bone plate absorption. In vivo, compared with the single group, the tumor volume and cell proliferation were significantly reduced, apoptosis and necrosis of tumor cells increased, and TRAP⁺ osteoclasts and osteolysis destruction decreased in the combined group. In conclusion, ZA enhanced the antitumor effect of cisplatin on osteosarcoma by ROS-PI3K/AKT signaling, reducing the chemoresistance and osteoclast activation to enhance chemotherapy and inhibit osteolysis. And this present study raised the possibility that combining ZA and cisplatin may represent a novel strategy against osteosarcoma.

Osteosarcoma: a review of current and future therapeutic approaches

Osteosarcoma (OS) is the most common primary bone malignancy that affects children and young adults. OS is characterized by a high degree of malignancy, strong invasiveness, rapid disease progression, and extremely high mortality rate; it is considered as a serious threat to the human health globally. The incidence of OS is common in the metaphysis of long tubular bones, but rare in the spine, pelvis, and sacrum areas; moreover, majority of the OS patients present with only a single lesion. OS has a bimodal distribution pattern, that is, its incidence peaks in the second decade of life and in late adulthood. We examine historical and current literature to present a succinct review of OS. In this review, we have discussed the types, clinical diagnosis, and modern and future treatment methods of OS. The purpose of this article is to inspire new ideas to develop more effective therapeutic options.

Nanotube Active Water Pump Driven by Alternating Hydrophobicity

Water transport must be efficiency controlled for the future sustainability of life. Various water transport systems using carbon nanotubes have been proposed in recent years. Although these systems are more permeable than aquaporins, their water transport is passive. In this study, we successfully demonstrate an active water pump driven by simple hydrophobic interaction through computer simulation. Even in the absence of a pressure- or density-gradient, the proposed pump can actively transport water molecules by alternately switching the hydrophobicity of the pump surface. The water transport rate can be easily controlled by varying the time interval of switching. The pump with optimized switching time exhibits prominent water permeance. The results obtained herein can be applied in various water transport technologies because of the simple mechanics. The proposed water pump has the potential to realize an effective device such as a low-energy artificial purification system.

Mechanisms of Resistance to Conventional Therapies for Osteosarcoma

Osteosarcoma (OS) is the most common primary bone tumor, mainly occurring in children and adolescents. Current standard therapy includes tumor resection associated with multidrug chemotherapy. However, patient survival has not evolved for the past decades. Since the 1970s, the 5-year survival rate is around 75% for patients with localized OS but dramatically drops to 20% for bad responders to chemotherapy or patients with metastases. Resistance is one of the biological processes at the origin of therapeutic failure. Therefore, it is necessary to better understand and decipher molecular mechanisms of resistance to conventional chemotherapy in order to develop new strategies and to adapt treatments for patients, thus improving the survival rate. This review will describe most of the molecular mechanisms involved in OS chemoresistance, such as a decrease in intracellular accumulation of drugs, inactivation of drugs, improved DNA repair, modulations of signaling pathways, resistance linked to autophagy, disruption in genes expression linked to the cell cycle, or even implication of the micro-environment. We will also give an overview of potential therapeutic strategies to circumvent resistance development.

High Dose Ifosfamide in Relapsed and Unresectable High-Grade Osteosarcoma Patients: A Retrospective Series

Background: The evidence on high-dose ifosfamide (HD-IFO) use in patients with relapsed osteosarcoma is limited. We performed a retrospective study to analyze HD-IFO activity. Methods: Patients with osteosarcoma relapsed after standard treatment [methotrexate, doxorubicin, cisplatin +/- ifosfamide (MAP+/-I)] with measurable disease according to RECIST1.1 were eligible to ifosfamide (3 g/m2/day) continuous infusion (c.i.) days 1-5 q21d. RECIST1.1 overall response rate (ORR) (complete response (CR) + partial response (PR)), progression-free survival at 6-month (6m-PFS), duration of response (DOR), and 2-year overall survival (2y-OS) were assessed. PARP1 expression and gene mutations were tested by immunohistochemistry and next-generation sequencing. Results: 51 patients were included. ORR was 20% (1 CR + 9 PR). Median DOR was 5 months (95%CI 2-7). Median PFS, 6m-PFS, OS, and 2y-OS were 6 months (95%CI 4-9), 51%, 15 months (10-19), and 30%, respectively. A second surgical complete remission (CR2) was achieved in 26 (51%) patients. After multivariate analysis, previous use of ifosfamide (HR 2.007, p = 0.034) and CR2 (HR 0.126, p < 0.001) showed a significant correlation with PFS and OS, respectively. No significant correlation was found between outcomes and PARP1 or gene mutations. Conclusions: HD-IFO should be considered as the standard first-line treatment option in relapsed osteosarcoma and control arm of future trial in this setting.

Tumor-Treating Fields Inhibit the Metastatic Potential of Osteosarcoma Cells

The prognosis of metastatic osteosarcoma (OS) remains poor with a <20% survival rate, particularly in cases of distant (non-lung) metastases. Tumor-treating field (TTF) therapy is a novel electric field-based treatment that causes metaphase arrest and tumor cell death, with the advantage of reduced side effects compared to radiation and chemotherapy. TTF shows promise in glioblastoma and other solid tumors; however, few studies have examined its potential in the treatment of osteosarcoma. Therefore, we explored the mechanism of TTF-induced metastasis inhibition and cell death using in vitro models. TTF (1.5 V/cm, 150 kHz) was applied to U2OS and KHOS/NP OS cell lines. In addition, a 3-dimensional culture system was established using these OS cell lines. Cell migration and invasion (i.e., metastatic potential) were examined using a wound-healing scratch assay and transwell assay, respectively. Western blotting of metastasis- and angiogenesis-related proteins was performed. TTF suppressed the migration of and invasion by OS cells and inhibited the expression of epithelial markers, thereby preventing epithelial-mesenchymal transition (EMT), a hallmark of metastasis. Moreover, TTF prevented angiogenesis in human tumor endothelial cells and downregulated matrix metalloproteinase-2 (MMP2) and vascular endothelial growth factor (VEGF) expression. Therefore, TTF shows potential as an improved treatment for osteosarcoma, warranting further preclinical studies in animal models to support clinical trials.

Ascorbate sensitizes human osteosarcoma cells to the cytostatic effects of cisplatin

Osteosarcoma (OS) is the most common malignant bone tumor and a leading cause of cancer-related deaths in children and adolescents. Current standard treatments for OS are a combination of preoperative chemotherapy, surgical resection, and adjuvant chemotherapy. Cisplatin is used as the standard chemotherapeutic for OS treatment, but it induces various adverse effects, limiting its clinical application. Improving treatment efficacy without increasing the cisplatin dosage is desirable. In the present study, we assessed the combined effect of ascorbate on cisplatin treatment using cultured human OS cells. Co-treatment with ascorbate induced greater suppression of OS cell but not nonmalignant cell proliferation. The chemosensitizing effect of ascorbate on cisplatin treatment was tightly linked to ROS production. Altered cellular redox state due to increased ROS production modified glycolysis and mitochondrial function in OS cells. In addition, OS cell sphere formation was markedly decreased, suggesting that ascorbate increased the treatment efficacy of cisplatin against stem-like cells in the cancer cell population. We also found that enhanced MYC signaling, ribosomal biogenesis, glycolysis, and mitochondrial respiration are key signatures in OS cells with cisplatin resistance. Furthermore, cisplatin resistance was reversed by ascorbate. Taken together, our findings provide a rationale for combining cisplatin with ascorbate in therapeutic strategies against OS.

Midterm Success of a Custom, Non-Fluted, Diaphyseal, Press-Fit Stem Used With a Tumor Megaprosthesis System

BACKGROUND

High rates of aseptic loosening with cemented prostheses have led to increased utilization of uncemented stems in the setting of megaprosthetic reconstruction. Theoretic concerns of rotational instability resulted in early stem designs with de-rotational mechanisms such as flutes or side plates. However, these designs have their own associated complications, and mechanical data suggest they are unnecessary. The purpose of this study is to evaluate outcomes and survivorship of an unfluted diaphyseal press-fit stem in the setting of megaprosthetic reconstruction.

METHODS

Forty-five patients (46 stems), with a minimum 3-year follow-up, underwent reconstruction using 1 of 2 fully porous coated, unfluted, press-fit stems between 2005 and 2013: revision stem with adapter to the megaprosthesis (revision stem), or custom megaprosthesis stem (custom stem). Complications were described using the Henderson classification system, and subanalyses evaluated stem-related failures and survival. Radiographic evaluation of stem fixation was determined via evidence of bone bridging, spot welding, resorption, subsidence, and pedestal formation. Four patients had early stem removal for local recurrence or infection and were thus excluded from the radiographic analyses.

RESULTS

Twenty-eight femoral (15 revision stem, 13 custom stem) and 14 tibial (6 revision stem, 8 custom stem) stems were reviewed. Average follow-up was 81 months (range, 42-140 months). Revision for implant-related complications occurred in 7 of 41 (17%), all in revision stems (3 adapter failures, 4 polyethylene wear). At final follow-up, all stems were retained without evidence of aseptic loosening, although 7 of 41 (17%) exhibited mild stress shielding.

CONCLUSION

A non-fluted, press-fit stem used with a tumor prosthesis provided a stable bone-prosthesis interface at midterm follow-up.

MT2A is an early predictive biomarker of response to chemotherapy and a potential therapeutic target in osteosarcoma

Osteosarcoma is the most prevalent primary bone malignancy in children and young adults. Resistance to chemotherapy remains a key challenge for effective treatment of patients with osteosarcoma. The aim of the present study was to investigate the preventive role of metallothionein-2A (MT2A) in response to cytotoxic effects of chemotherapy. A panel of human and murine osteosarcoma cell lines, modified for MT2A were evaluated for cell viability, and motility (wound healing assay). Cell-derived xenograft models were established in mice. FFPE tumour samples were assessed by IHC. In vitro experiments indicated a positive correlation between half-maximal inhibitory concentration (IC50) for drugs in clinical practice, and MT2A mRNA level. This reinforced our previously reported correlation between MT2A mRNA level in tumour samples at diagnosis and overall survival in patients with osteosarcoma. In addition, MT2A/MT2 silencing using shRNA strategy led to a marked reduction of IC50 values and to enhanced cytotoxic effect of chemotherapy on primary tumour. Our results show that MT2A level could be used as a predictive biomarker of resistance to chemotherapy, and provide with preclinical rational for MT2A targeting as a therapeutic strategy for enhancing anti-tumour treatment of innate chemo-resistant osteosarcoma cells.

Primary osteosarcoma in elderly patients: A report of three cases

Osteosarcoma is the most common type of primary malignant bone tumor in children and young adults. However, primary osteosarcoma in elderly patients is rare. The present study reports 3 cases of advanced osteosarcoma in elderly patients. The pathological findings in all 3 cases confirmed the diagnosis of primary osteosarcoma. Notably, each patient received different treatment options. Chemoradiotherapy was recommended in case 1 due to the age of the patient. However, the patient requested to be discharged and was lost to follow-up. Conversely, in case 2, the 62-year-old female patient underwent systemic chemotherapy, but no surgical treatment, and in case 3, the 51-year-old male patient underwent complete tumor resection and received systemic chemotherapy for late tumor recurrence. Early diagnosis of osteosarcoma in elderly patients is difficult, and misdiagnosis or a missed diagnosis is common. In clinical practice, bone tumors in elderly patients should be investigated carefully. Imaging examinations are essential for diagnosis, and biopsy is required for confirmation. However, the efficacy of chemotherapy for elderly patients with primary osteosarcoma remains uncertain. Collectively, due to the small number of reports of osteosarcoma in the elderly population, the 3 cases in the present study raise awareness of this rare condition.

BTF3 Silencing Inhibits the Proliferation of Osteosarcoma Cells

Osteosarcoma (OS) is one of the bone malignancy cancers with poor prognosis in the early stages worldwide. Basic transcription factor 3 (BTF3) is associated with the development of several types of cancer. The present study aimed to evaluate the role of BTF3 in OS. Silencing of BTF3 was achieved by using stable lentivirus transfection of siRNA targeting BTF3 in the human OS cell line Saos-2. Cell viability and colony-forming ability were measured using methyl-thaizolyl-tetrazolium (MTT) and colony formation assays, respectively. Propidium iodide staining and flow cytometry was used to detect the progression of the cell cycle. To evaluate the possible intracellular signaling molecules involved, a PathScan Intracellular Signaling Array Kit was utilized. Lentivirus-BTF3-shRNA (LV-BTF3-shRNA) suppressed expression of BTF3 in Saos-2 cells (inhibition ratio: 89.8%), which significantly inhibited cell proliferation (48.5%), colony formation and enhanced apoptosis to 48.2% compared to 4.5% with lentivirus control shRNA (N-shRNA). Additionally, BTF3 silencing enhanced the percentage of Saos-2 cells in S and G₂/M phases, but significantly reduced cells in the G0/M phase (all P < 0.01). The proteins activated by BTF3 included STAT3, S6 ribosomal protein, HSP27 and SAPK/JNK2, all of which were inhibited by BTF3 silencing, whereas SAPK/JNK1 was upregulated by BTF3 silencing. In the present study, we explored the crucial role of BTF3 in promoting OS cell proliferation as well as laying the foundations for further research to investigate the clinical potential of lentivirus-mediated delivery of BTF3 interruption therapy for the treatment of OS.

Down-regulation of MRPS23 inhibits LPS-induced proliferation and invasion via regulation of the NF-κB signaling pathway in osteosarcoma cells

Mitochondrial ribosomal protein S23 (MRPS23), encoded by a nuclear gene, is a participant in the translation of mitochondrial proteins. Recently, MRPS23 has been reported to be overexpressed in many types of cancers and have a close association with cancer progression. However, the specific roles of MRPS23 in osteosarcoma (OS) remain unknown. In this study, we investigated the expression pattern and biological functions of MRPS23 in OS cells. Our results demonstrated that MRPS23 was up-regulated in OS tissues and cell lines. Down-regulation of MRPS23 significantly inhibited OS cell proliferation and invasion induced by lipopolysaccharide (LPS) in vitro. Furthermore, the in vivo experiments showed that MRPS23 down-regulation markedly suppressed OS cell growth and metastasis induced by LPS. Mechanistically, down-regulation of MRPS23 inhibited the activity of NF-κB signaling pathway in OS cells. In conclusion, these findings indicated that MRPS23 may be a potential therapeutic target for OS treatment.

Mitochondrial ribosomal protein S23 (MRPS23), encoded by a nuclear gene, is a participant in the translation of mitochondrial proteins.

Aurora B kinase as a novel molecular target for inhibition the growth of osteosarcoma

Osteosarcoma is the primary human malignant tumor affecting bone. This cancer most frequently arises in children and adolescents, with a second peak in those over the age of 50. Currently, surgery followed by radiotherapy and chemotherapy are the main treatments, but long-term positive effects are very poor. Aurora B kinase is a serine/threonine kinase that is a key regulator of cell cycle and mitosis. Tissue array analysis revealed that Aurora B kinase is overexpressed in osteosarcoma compared with normal bone tissue. We developed a compound, HOI-07 (i.e., (E)-3-((E)-4-(benzo[d] [1,3]dioxol-5-yl)-2-oxobut-3-en-1-ylidene)indolin-2-one), as a specific Aurora B kinase inhibitor and examined its effectiveness against osteosarcoma cell growth in this study. This compound inhibited Aurora B kinase activity in osteosarcoma and induced apoptosis, caused G2-M phase arrest, and attenuated osteosarcoma anchorage-independent cell growth. Moreover, knocking down the expression of Aurora B effectively reduced the sensitivity of osteosarcoma to HOI-07. Results of a xenograft mouse study indicated that HOI-07 treatment effectively suppressed the growth of 143B and KHOS xenografts, without affecting the body weight of mice. The expression of phosphorylated histone H3 (Ser10) was reduced in mice treated with HOI-07. Overall, we identified HOI-07 as a specific Aurora B kinase inhibitor for osteosarcoma treatment and this compound warrants further investigation.

MicroRNA‑466 inhibits cell proliferation and invasion in osteosarcoma by directly targeting insulin receptor substrate 1

Accumulating evidence has demonstrated that microRNAs (miRNAs) are frequently dysregulated in osteosarcoma (OS), and the aberrant expression of miRNAs is associated with OS initiation and progression. Previous studies demonstrated that miRNA‑466 (miR‑466) is dysregulated, and serves important roles in various types of human cancer. However, the role of miR‑466 in the formation and progression of OS remains unclear. In the present study, the expression level of miR‑466 was identified to be markedly downregulated in OS tissues and cell lines. Additionally, miR‑466 overexpression inhibited the proliferative and invasive abilities of OS cells. In the present study, bioinformatics analyses and luciferase assays were employed to show that miR‑466 was able to directly target the 3'‑untranslated region of insulin receptor substrate 1 (IRS1) gene, negatively regulating the mRNA and the protein expression levels of IRS1 in OS cells. Furthermore, IRS1 was upregulated in OS tissues, and the increased expression level of IRS1 exhibited an inverse correlation with the expression level of miR‑466. Furthermore, IRS1 overexpression was able to partially reverse the suppressive effects of miR‑466 overexpression in OS cells. To the best of the authors' knowledge, the present study is the first to suggest that miR‑466 is downregulated in OS and inhibits the progression of OS by directly targeting IRS1. The present results suggested that miR‑466 may represent a novel potential therapeutic target for the treatment of patients with OS.

Fascin-1 enhances experimental osteosarcoma tumor formation and metastasis and is related to poor patient outcome

Background

Fascin-1, a prominent actin-bundling protein, is found to be upregulated in several human carcinomas. While it is accepted that Fascin-1 expression correlates with poor clinical outcome and decreased survival in various carcinomas, its role in sarcoma such as osteosarcoma (OS) remains unknown. In the present study, we evaluated the prognostic value and biological relevance of Fascin-1 in OS.

Methods

The correlation between Fascin-1 expression and the outcome of OS patients was determined by immunohistochemistry analysis of Fascin-1 expression in a tissue microarray of OS tissue specimens collected during primary tumor resection. To examine the effect of Fascin-1, shRNA and overexpression technology to alter Fascin-1 levels in OS cells were used in cellular assays as well as in intratibial xenograft OS models in SCID mice.

Results

Kaplan-Meier survival analysis of Fascin-1 expression in OS tumor specimens revealed a direct relationship between Fascin-1 expression and poor patient survival. Furthermore, overexpression of Fascin-1 in OS cells significantly increased their migratory capacity as well as the activity of the matrix metalloprotease MMP-9, known to be critical for the execution of metastasis. Finally, using relevant xenograft mouse models, orthotopic intratibial transplantation of two different OS cell lines overexpressing Fascin-1 promoted tumor growth and lung metastasis.

Conclusions

Collectively, our findings demonstrate for the first time that Fascin-1 has considerable potential as a novel prognostic biomarker in OS, and suggest that targeting of Fascin-1 might be a new anti-metastatic strategy in OS patient treatment.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5303-3) contains supplementary material, which is available to authorized users.

Preparation of adriamycin gelatin microsphere-loaded decellularized periosteum that is cytotoxic to human osteosarcoma cells

The purpose of this study was to develop a novel approach to treat bone osteosarcoma using a multipurpose scaffold aiming for local drug delivery. The slowly releasing microspheres was designed to deliver the chemotherapy drug adriamycin (ADM) and a decellularized (D) periosteum scaffold (which is known to be able to promote bone regeneration) was used to carry these microspheres. D-periosteum was obtained by physical and chemical decellularization. Histological results showed that the cellular components were effectively removed. The D-periosteum showed an excellent cytocompatibility and the ability to promote adhesion and growth of fibroblasts. Two kinds of slowly releasing microspheres, adriamycin gelatin microspheres (ADM-GMS) and adriamycin poly (dl-lactide-co-glycolide) gelatin microspheres (ADM-PLGA-GMS), were prepared and anchored to D-periosteum, resulting in two types of drug-releasing regenerative scaffolds. The effectiveness of these two scaffolds in killing human osteosarcoma cells was tested by evaluating cell viability overtime of the cancer cells cultured with the scaffolds. In summary, a gelatin/decellularized periosteum-based biologic scaffold material was designed aiming for local delivery of chemotherapy drugs for osteosarcoma, with the results showing ability of the scaffolds in sustaining release of the cancer drug and in suppressing growth of the cancer cells in vitro.

A Novel Peptide from Vespa ducalis Induces Apoptosis in Osteosarcoma Cells by Activating the p38 MAPK and JNK Signaling Pathways

Osteosarcoma (OS) is a typical bone cancer, and most frequently used cancer treatments for OS are limited due to severe drug-related toxicities. Wasp venoms contain functional components that may offer pharmaceutical components for the treatment of cancers. This study aimed to isolate and characterize a novel peptide (venom anti-cancer peptide 1, VACP1) derived from the wasp venom of Vespa ducalis SMITH. Toxins from Vespa ducalis crude venom were separated by gel filtration and purified by C18 reverse-phase HPLC. As examined by Edman degradation, the amino acid sequence of VACP1 is AQKWLKYWKADKVKGFGRKIKKIWFG. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays revealed that VACP1 inhibited the cell proliferation of MG-63, U-2 OS and Saos-2 cells. Furthermore, annexin V and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) staining revealed that VACP1 could induce the apoptosis of OS cell lines. In addition, VACP1 increased the protein levels of cleaved poly ADP-ribose polymerase (PARP), caspase 3, but decreased B-cell lymphoma 2 (Bcl-2). Apoptotic signaling pathway screening in MG-63 cells via an antibody array revealed that VACP1 activated the p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK) pathways. The present study demonstrates that VACP1 potently suppressed cell proliferation and induced the cell apoptosis of OS cells by inducing the activation of the p38 MAPK and JNK signaling pathways, suggesting that VACP1 is a promising agent for OS therapy.

The multidisciplinary treatment of osteosarcoma of the proximal tibia: a retrospective study

Background

Survival and reconstruction constitute important challenges in multimodal treatment of osteosarcoma of the proximal tibia. The purpose of this study was to assess the efficacy and prognosis of neoadjuvant chemotherapy and custom-designed endoprosthetic arthroplasty.

Methods

A total of 69 patients with osteosarcoma of the proximal tibia were evaluated, including 43 males and 26 females, treated with multidisciplinary limb-salvage remedy from October 2003 to December 2013. They were at least 12 years old (mean, 20 years; range, 12–57 years). The gap between tumor and main artery/nerve was showed in MRI. Mean follow up was 69.5 months (range, 9–144 months). Kaplan-Meier survival curves were generated to assess prognosis and relapse rate. The initial symptoms and disease duration for each patient were recorded. Correlation analyses were performed for the association of various parameters with prognosis. Functional outcomes were evaluated using the Musculoskeletal Tumor Society (MSTS) guidelines after 6 months postoperatively, to analyze the relation between bone excision size and function recovery.

Results

The resection lengths measured intraoperatively ranged from 80 to 230 mm, and contained 3 cm of normal bone around the tumor. A total of 3 courses of preoperative chemotherapy were administered to all cases. At final follow-up, 1 case showed recurrence. Meanwhile, 8 patients (11.6%) died from lung metastasis. Post-operative infection occurred in 3 patients; 1 case was maintained with revision surgery. Two cases underwent amputation. The mean MSTS system score was 21.6.

Conclusions

The multidisciplinary treatment result in an overall positive outcome, with improved function.

MicroRNA‑22 inhibits the proliferation and migration, and increases the cisplatin sensitivity, of osteosarcoma cells

Osteosarcoma (OS) is the major type of primary bone tumor and is associated with a poor prognosis due to chemotherapy resistance. Accumulating evidence indicates that microRNAs (miRNAs/miRs) may influence the tumor progression of OS and cell sensitivity to chemotherapy. In the present study, a total of 7 patients with OS and 7 healthy volunteers were recruited. Reverse transcription-quantitative polymerase chain reaction and ELISA were performed to determine the expression of miRNAs and mRNAs in the serum of participants. Furthermore, the biological function of miR-22 and S100A11 was examined in MG-63 cells using Cell Counting Kit-8 assays, Transwell migration assays and western blot analysis to determine the effects on cell proliferation, migration and protein expression, respectively, while MG-63 cell sensitivity to cisplatin was assessed by measuring cell viability following cisplatin treatment and calculating the half maximal inhibitory concentration (IC₅₀). Additionally, the association between miR-22 and S100 calcium-binding protein A11 (S100A11) was validated using a luciferase reporter assay. The results demonstrated that miR-22 expression was significantly reduced in patients with OS and the MG-63 OS cell line, compared with healthy volunteers and the normal osteoblast hFOB 1.19 cell line, respectively, while the expression of S100A11 was negatively associated with miR-22 levels in the MG-63 cell line. Furthermore, overexpression of miR-22 inhibited the proliferation and migratory ability of MG-63 cells, and increased the sensitivity of MG-63 cells to cisplatin treatment; however, overexpression of S100A11 partially attenuated the alterations in proliferation, migratory ability and chemosensitivity that were induced by miR-22 overexpression. In addition, it was confirmed that S100A11 is a direct target gene of miR-22 in MG-63 cells. In conclusion, to the best of our knowledge, the present study is the first to demonstrate that miR-22 may be a promising therapeutic target and may have potential as part of a combination treatment alongside chemotherapeutic agents for OS.

Comparison of Tumor- and Bone Marrow-Derived Mesenchymal Stromal/Stem Cells from Patients with High-Grade Osteosarcoma

Osteosarcoma (OS) is suspected to originate from dysfunctional mesenchymal stromal/stem cells (MSC). We sought to identify OS-derived cells (OSDC) with potential cancer stem cell (CSC) properties by comparing OSDC to MSC derived from bone marrow of patients. This study included in vitro characterization with sphere forming assays, differentiation assays, cytogenetic analysis, and in vivo investigations of their tumorigenicity and tumor supportive capacities. Primary cell lines were isolated from nine high-grade OS samples. All primary cell lines demonstrated stromal cell characteristics. Compared to MSC, OSDC presented a higher ability to form sphere clones, indicating a potential CSC phenotype, and were more efficient at differentiation towards osteoblasts. None of the OSDC displayed the complex chromosome rearrangements typical of high grade OS and none of them induced tumors in immunodeficient mice. However, two OSDC demonstrated focused genomic abnormalities. Three out of seven, and six out of seven OSDC showed a supportive role on local tumor development, and on metastatic progression to the lungs, respectively, when co-injected with OS cells in nude mice. The observation of OS-associated stromal cells with rare genetic abnormalities and with the capacity to sustain tumor progression may have implications for future tumor treatments.

Targeting αvβ3 and αvβ5 integrins inhibits pulmonary metastasis in an intratibial xenograft osteosarcoma mouse model

Osteosarcoma is an aggressive bone cancer that has a high propensity for metastasis to the lungs. Patients with metastatic disease face a very poor prognosis. Therefore, novel therapeutics, efficiently suppressing the metastatic process, are urgently needed. Integrins play a pivotal role in tumor cell adhesion, motility and metastasis. Here, we evaluated αvβ3 and αvβ5 integrin inhibition with cilengitide as a novel metastasis-suppressive therapeutic approach in osteosarcoma. Immunohistochemical analysis of αvβ3 and αvβ5 integrins expression in a tissue microarray of tumor specimens collected from osteosarcoma patients revealed that αvβ5 integrin is mainly found on tumor cells, whereas αvβ3 is predominantly expressed by stromal cells. In vitro functional assays demonstrated that cilengitide dose-dependently inhibited de novo adhesion, provoked detachment and inhibited migration of osteosarcoma cell lines. Cilengitide induced a decline in cell viability, blocked the cell cycle in the G1 phase and caused anoikis by activation of the Hippo pathway. In a xenograft orthotopic mouse model cilengitide minimally affected intratibial primary tumor growth but, importantly, suppressed pulmonary metastasis. The data demonstrate that targeting αvβ3 and αvβ5 integrins in osteosarcoma should be considered as a novel therapeutic option for patients with metastatic disease.

Extraskeletal osteosarcoma: A large series treated at a single institution

Purpose: This study is to present a large cohort of extraskeletal osteosarcoma (ESOS) and evaluate prognostic factors and treatment options. Methods: Medical records were reviewed retrospectively for 41 patients with extraskeletal osteosarcoma that was diagnosed by pathology, and treated at our institution between 1960 and 2016. Kaplan-Meier analysis and Cox proportional hazards regression were used to identify variables that affect survival outcomes. Results: 41 patients were identified from 952 osteosarcomas. 32 patients had non-metastatic disease. Prognostic factors were identified by univariate analysis and multi-variate analysis. Surgery (p<0.001), and surgery type (p<0.001) both were shown to significantly affect overall survival (OS). Chemotherapy and radiation therapy (RT) did not show any significant effect on OS, local recurrence, or progression free survival as a whole. However for patients who had incomplete resection with residual tumor RT improved OS (p=0.03). The survival curve for ESOS follows more closely that of non-rhabdomyosarcoma soft tissue sarcomas (NRSTS). Conclusions: ESOS is a very rare tumor. Attempt to achieve wide resection is the treatment of choice. However for patients who are not able to achieve complete resection, RT may improve OS. The behavior of ESOS more closely follows that of NRSTS than osteosarcoma of the bone.

Limb Salvage Versus Amputation in Conventional Appendicular Osteosarcoma: a Systematic Review

The overall survivorship in patients with appendicular osteosarcoma has increased in the past few decades. However, controversies and questions about performing an amputation or a limb salvage procedure still remain. Using three peer-reviewed library databases, a systematic review of the literature was performed to evaluate all studies that have evaluated the outcomes of appendicular osteosarcoma, either with limb salvage or amputation. The mean 5-year overall survivorship was 62% for salvage and 58% for amputation (p > 0.05). At mean 6-year follow-up, the local recurrence rates were 8.2% for salvage and 3.0% for amputation (p > 0.05). Additionally, at mean 6-year follow-up, the rate for metastasis was 33% for salvage and 38% for amputation (p > 0.05). The revision rates were higher with salvage (31 vs. 28%), and there were more complications in the salvage groups (52 vs. 34%; p > 0.05). Despite the heterogeneity of studies available for review, we observed similar survival rates between the two procedures. Although there was no significant statistical difference between rates of recurrence and metastasis, the local recurrence rate and risk of complications were higher for limb salvage as compared to amputation. Cosmetic satisfaction is often higher with limb salvage, whereas long-term expense is higher with amputation. Overall, current literature supports limb salvage procedures when wide surgical margins can be achieved while still retaining a functional limb.

L‑mimosine induces caspase‑9‑mediated apoptosis in human osteosarcoma cells

L-mimosine is a rare plant amino acid extracted from Mimosa or Leucaena spp., and it has been reported to exhibit antitumor activity in a number of types of cancer. However, the underlying mechanisms remain to be clarified. In the present study, the effect of L‑mimosine was investigated in human osteosarcoma cells. A Cell Counting Kit‑8 assay and flow cytometry were used for toxicity detection. Hoechst staining and transmission electron microscopy (TEM), in addition to western blot analysis, were used for the examination of the associated mechanisms. The results of the present study indicated that L‑mimosine significantly inhibited cell proliferation by inducing cellular apoptosis in osteosarcoma cells. The Hoechst staining results and TEM revealed that nuclear damage increased with the concentration increase in L‑mimosine, as did the formation of apoptotic bodies. Additionally, the results of the western blot analysis confirmed that the treatment of cells with L‑mimosine was accompanied by increasing expression of cleaved caspase‑9. L‑mimosine‑induced apoptosis was inhibited by the caspase‑9 inhibitor Z‑LEHD‑FMK. In addition, the extracellular signal‑regulated kinase (ERK) signaling pathway was suppressed following treatment with L‑mimosine. In conclusion, the results of the present study suggested that L‑mimosine induced apoptosis via the mitochondrial apoptotic pathway. The ERK signaling pathway was indicated to be an additional mechanism underlying apoptosis induction. The results provided evidence for the use of L‑mimosine as a promising candidate for osteosarcoma therapy.

Antitumor effects of pristimerin on human osteosarcoma cells in vitro and in vivo

There are very few treatments for musculoskeletal tumors, compared to other cancers; thus, novel therapeutic drugs are needed. Pristimerin (PM) is a triterpene compound isolated from plant extracts that reportedly has antitumor effects on various cancers, such as of the breast and prostate. The purpose of this study was to evaluate the antitumor effects of PM on human osteosarcoma cells. Treatment of the human osteosarcoma cell lines, MNNG and 143B, with PM led to a dose-dependent decrease in cell viability. The effects of PM on apoptosis were evaluated with the Annexin V/propidium iodide assay and analysis of caspases 3, 8, and 9 activities. Western blot analysis showed that PM caused a decrease in the expression of Akt, mTOR, and NF-κB. The volumes and weights of human osteosarcoma xenografts decreased significantly with PM treatment. The results of this study revealed that PM can inhibit human osteosarcoma growth in vitro and in vivo, and may be a novel therapeutic agent for the disease.

Inhibition of autophagy attenuated curcumol-induced apoptosis in MG-63 human osteosarcoma cells via Janus kinase signaling pathway

The present study aimed to investigate whether autophagy was triggered by curcumol and to explore the association between autophagy and apoptosis of MG-63 cells and the underlying mechanism. MG-63 cells were cultured in vitro. An MTT assay was performed to evaluate the proliferation inhibition of the MG-63 osteosarcoma cell line by curcumol. Fluorescein isothiocyanate-Annexin V/propidium iodide staining flow cytometry was performed to analyze the apoptotic rate of cells. The morphological alterations of cell nuclei were evaluated by Hoechst 33258 viable cell staining. The effects of autophagy in cells was investigated by green fluorescent protein (GFP)-light chain 3 (LC3) transfection and using a fluorescence microscope. The expression levels of LC3II, LC3I and cleaved caspase-3 and Janus kinase (JNK) signaling pathway activation were determined by western blot analysis. Cell proliferation was inhibited by curcumol in a dose- and time-dependent manner. Curcumol induced apoptosis by the caspase-dependent signaling pathway in MG-63 cells. The present study demonstrated that curcumol could induce autophagy of MG-63 cells, which was evaluated by transmission electron microscopy. Compared with the curcumol treatment alone group, the GFP-LC3-transfected green fluorescence plasmids and the LC3II/LC3I levels in cells of the curcumol and chloroquine (CQ) treatment group were upregulated, and the apoptotic ratio was downregulated following pretreatment with autophagy inhibitor CQ for 1 h. Furthermore, curcumol treatment induced phosphorylation of the JNK signaling pathway. Of note, pretreatment with the JNK inhibitor, SP600125, decreased the rates of autophagy and apoptosis, suggesting a crucial role served by the JNK signaling pathway in the activation of autophagy by curcumol. Taken together, the results of the present study suggested that activation of the JNK signaling pathway was involved in curcumol-induced autophagy. Curcumol is a novel drug for chemotherapeutic combination therapy. Curcumol demonstrated potential antitumor activities in MG-63 cells and may be used as a novel effective reagent in the treatment of osteosarcoma.