Vascular pattern in enchondroma and chondrosarcoma: clinical and immunohistologic study

IMP3, CDK4, MDM2 and β-catenin expression in Enchondroma and Central Chondrosarcoma: Diagnostic and prognostic utility

INTRODUCTION

The role of IMP3, CDK4, MDM2 and β-catenin proteins in Enchondroma and Central Chondrosarcoma is not totally understood. The aim of this study is to evaluate the immunoexpression of these proteins, associating histological grade, clinical data and prognosis to these tumors.

METHODS

This is a retrospective-analytical study of 32 Enchondroma and 70 Central Chondrosarcoma.

RESULTS

IMP3, CDK4, MDM2 and β-catenin expression was observed in 22.82 %, 13.82 %, 17.17 % and in 8.8 % of cases, respectively. All Enchondromas positive for these immunomarkers were located in short tubular bones. The positivity for these antibodies is directly proportional to Chondrosarcoma's histological grade increase. No difference was found between Enchondroma and Chondrosarcoma, Grade 1 for IMP3, CDK4 and ß-catenin positivity. Significant metastasis outcome was observed for IMP3, CDK4, MDM2 and death for MDM2 expression.

CONCLUSION

IMP3, CDK4, MDM2 and β-catenin expression in Enchondromas of short bones phenotypically characterizes these tumors. Their expression has not proven to be useful either as diagnostic markers of these neoplasms or in distinguishing between Enchondroma and Chondrosarcoma, Grade 1. The significant immunoexpression of IMP3, CDK4 and MDM2 in metastatic Chondrosarcoma and the lower survival in those with positivity for MDM2 suggest a possible association of these proteins with tumor aggressiveness.

Additive Manufacturing of Iron Carbide Incorporated Bioactive Glass Scaffolds for Bone Tissue Engineering and Drug Delivery Applications

In this study, we have synthesized a bioactive glass with composition 45SiO2-20Na2O-23CaO-6P2O5-2.5B2O3-1ZnO-2MgO-0.5CaF2 (wt %). Further, it has been incorporated with 0.4 wt % iron carbide nanoparticles to prepare magnetic bioactive glass (MBG) with good heat generation capability for potential applications in magnetic field-assisted hyperthermia. The MBG scaffolds have been fabricated using extrusion-based additive manufacturing by mixing MBG powder with 25% Pluronic F-127 solution as the binder. The saturation magnetization of iron carbide nanoparticles in the bioactive glass matrix has been found to be 80 emu/g. The morphological analysis (pore size distribution, porosity, open pore network modeling, tortuosity, and pore interconnectivity) was done using an in-house developed methodology that revealed the suitability of the scaffolds for bone tissue engineering. The compressive strength (14.3 ± 1.6 MPa) of the MBG scaffold was within the range of trabecular bone. The in vitro test using simulated body fluid (SBF) showed the formation of apatite indicating the bioactive nature of scaffolds. Further, the drug delivery behaviors of uncoated and polycaprolactone (PCL) coated MBG scaffolds have been evaluated by loading an anticancer drug (Mitomycin C) onto the scaffolds. While the uncoated scaffold demonstrated the drug's burst release for the initial 80 h, the PCL-coated scaffold showed the gradual release of the drug. These results demonstrate the potential of the proposed MBG for bone tissue engineering and drug delivery applications.

Role of immunotherapy in chondrosarcoma: A case report and review of the literature

Chondrosarcomas (CSs) consist of a heterogenous group of primary bone cancers arising from malignant cells which produce cartilaginous matrix. As the second most common primary bone cancer, CS are often resistant to systemic chemotherapy due to poor vascularization, slow proliferation, and expression of multidrug-resistant pumps. Immune checkpoint inhibitors have transformed the field of oncology and are now designated as frontline therapy for many solid tumor cancers. Several studies have demonstrated increased expression of programed cell death 1 (PD-1) and PD-L1 in CS tissue in vitro, which has led to the development of multiple clinical trials for immunotherapy in patients with aggressive CS. In this review, we highlight the ongoing investigation into the role for immunotherapy in CS. We also report the case of a 44-year-old female with a history of stage IV primary CS of the right shoulder who underwent radical resection with recurrence and demonstrated a spectacular sustained response to pembrolizumab at our center. Our review highlights the need for further studies investigating the role of immunotherapy in the treatment of aggressive bone sarcomas that are resistant to standard surgical resection, chemotherapy, and radiation treatment.

Expression of Amphiregulin in Enchondromas and Central Chondrosarcomas

OBJECTIVES

The aim of this study was to evaluate the role of amphiregulin protein, an epidermal growth factor receptor ligand, in cartilaginous tumors.

METHODS

Amphiregulin expression was examined in 31 enchondromas and 67 chondrosarcomas using immunohistochemistry analysis.

RESULTS

Overall, 15 enchondromas (48.40%) and 24 chondrosarcomas (35.82%) were positive for amphiregulin. According to the receiver operating characteristic curve test, no difference in amphiregulin expression was observed between enchondromas and low-grade chondrosarcomas (p=0.0880). Additionally, 39 lesions (16 in short bones, 13 in long bones, and 10 in flat bones) were positive for amphiregulin, exhibiting a higher percentage of positive cells (p=0.0030) and intensity of immunohistochemical expression (p=0.0055) in short bone lesions than in others. Among 25 enchondromas localized in short bones, 15 expressed amphiregulin; however, all 6 cases localized in long bones were negative for this marker (p=0.0177).

CONCLUSIONS

Amphiregulin did not help in distinguishing enchondromas from low-grade chondrosarcomas. The present study is the first to document the expression of this immunohistochemical marker in enchondromas. Furthermore, amphiregulin expression in enchondromas was localized in short bones, indicating a phenotypic distinction from that in long bones. This distinction may contribute to an improved understanding of the pathogenesis of these lesions.

Exosomes in Bone Sarcomas: Key Players in Metastasis

Bone sarcomas are rare cancers which often present with metastatic disease and are still associated with poor survival rates. Studies in the last decade have identified that exosomes, a type of extracellular vesicle released by cells, play an important role in tumour progression and dissemination. Through the transfer of their cargo (RNAs, proteins, and lipids) across cells, they are involved in cellular cross-talk and can induce changes in cellular behaviour. Exosomes have been shown to be important in metastasis organotropism, induction of angiogenesis and vascular permeability, the education of cells towards a pro-metastatic phenotype or the interaction between stromal and tumour cells. Due to the importance exosomes have in disease progression and the high incidence of metastasis in bone sarcomas, recent studies have evaluated the implications of these extracellular vesicles in bone sarcomas. In this review, we discuss the studies that evaluate the role of exosomes in osteosarcoma, Ewing sarcoma, and preliminary data on chondrosarcoma.

An Insight into the Roles of MicroRNAs and Exosomes in Sarcoma

Sarcomas are rare solid tumors, but at least one-third of patients with sarcoma die from tumor-related disease. MicroRNA (miRNA) is a noncoding RNA that regulates gene expression in all cells and plays a key role in the progression of cancers. Recently, it was identified that miRNAs are transferred between cells by enclosure in extracellular vesicles, especially exosomes. The exosome is a 100 nm-sized membraned vesicle that is secreted by many kinds of cells and contains miRNA, mRNA, DNA, and proteins. Cancer uses exosomes to influence not only the tumor microenvironment but also the distant organ to create a premetastatic niche. The progression of sarcoma is also regulated by miRNAs and exosomes. These miRNAs and exosomes can be targeted as biomarkers and treatments. In this review, we summarize the studies of miRNA and exosomes in sarcoma.

Chondrosarcoma: A Rare Misfortune in Aging Human Cartilage? The Role of Stem and Progenitor Cells in Proliferation, Malignant Degeneration and Therapeutic Resistance

Unlike other malignant bone tumors including osteosarcomas and Ewing sarcomas with a peak incidence in adolescents and young adults, conventional and dedifferentiated chondrosarcomas mainly affect people in the 4th to 7th decade of life. To date, the cell type of chondrosarcoma origin is not clearly defined. However, it seems that mesenchymal stem and progenitor cells (MSPC) in the bone marrow facing a pro-proliferative as well as predominantly chondrogenic differentiation milieu, as is implicated in early stage osteoarthritis (OA) at that age, are the source of chondrosarcoma genesis. But how can MSPC become malignant? Indeed, only one person in 1,000,000 will develop a chondrosarcoma, whereas the incidence of OA is a thousandfold higher. This means a rare coincidence of factors allowing escape from senescence and apoptosis together with induction of angiogenesis and migration is needed to generate a chondrosarcoma. At early stages, chondrosarcomas are still assumed to be an intermediate type of tumor which rarely metastasizes. Unfortunately, advanced stages show a pronounced resistance both against chemo- and radiation-therapy and frequently metastasize. In this review, we elucidate signaling pathways involved in the genesis and therapeutic resistance of chondrosarcomas with a focus on MSPC compared to signaling in articular cartilage (AC).