An mTOR and VEGFR inhibitor combination arrests a doxorubicin resistant lung metastatic osteosarcoma in a PDOX mouse model

Recent advances and future directions on small molecule VEGFR inhibitors in oncological conditions

"A journey of mixed emotions" is a quote that best describes the progress chart of vascular endothelial growth factor receptor (VEGFR) inhibitors as cancer therapeutics in the last decade. Exhilarated with the Food and Drug Administration (FDA) approvals of numerous VEGFR inhibitors coupled with the annoyance of encountering the complications associated with their use, drug discovery enthusiasts are on their toes with an unswerving determination to enhance the rate of translation of VEGFR inhibitors from preclinical to clinical stage. The recently crafted armory of VEGFR inhibitors is a testament to their growing dominance over other antiangiogenic therapies for cancer treatment. This review perspicuously underscores the earnest attempts of the researchers to extract the antiproliferative potential of VEGFR inhibitors through the design of mechanistically diverse structural assemblages. Moreover, this review encompasses sections on structural/molecular properties and physiological functions of VEGFR, FDA-approved VEGFR inhibitors, and hurdles restricting the activity range/clinical applicability of VEGFR targeting antitumor agents. In addition, tactics to overcome the limitations of VEGFR inhibitors are discussed. A clear-cut viewpoint transmitted through this compilation can provide practical directions to push the cart of VEGFR inhibitors to advanced-stage clinical investigations in diverse malignancies.

Amicis Omnia Sunt Communia: NF-κB Inhibition as an Alternative to Overcome Osteosarcoma Heterogeneity

Tumor heterogeneity poses a significant challenge in osteosarcoma (OS) treatment. In this regard, the "omics" era has constantly expanded our understanding of biomarkers and altered signaling pathways (i.e., PI3K/AKT/mTOR, WNT/β-catenin, NOTCH, SHH/GLI, among others) involved in OS pathophysiology. Despite different players and complexities, many commonalities have been described, among which the nuclear factor kappa B (NF-κB) stands out. Its altered activation is pervasive in cancer, with pleiotropic action on many disease-relevant traits. Thus, in the scope of this article, we highlight the evidence of NF-κB dysregulation in OS and its integration with other cancer-related pathways while we summarize the repertoire of compounds that have been described to interfere with its action. In silico strategies were used to demonstrate that NF-κB is closely coordinated with other commonly dysregulated signaling pathways not only by functionally interacting with several of their members but also by actively participating in the regulation of their transcription. While existing inhibitors lack selectivity or act indirectly, the therapeutic potential of targeting NF-κB is indisputable, first for its multifunctionality on most cancer hallmarks, and secondly, because, as a common downstream effector of the many dysregulated pathways influencing OS aggressiveness, it turns complex regulatory networks into a simpler picture underneath molecular heterogeneity.

Activity of pazopanib in EWSR1-NFATC2 translocation-associated bone sarcoma

Pazopanib is a multi-kinase inhibitor that is currently approved for treatment of advanced renal cell carcinoma and chemotherapy-refractory soft tissue sarcoma. In this case report, we discuss the case of a patient with a EWSR1-NFATC2 fusion positive bone sarcoma who had exceptional tumor control through using pazopanib and surgery for an overall duration exceeding 5 years. We also review the literature on EWSR1-NFATC2 translocation-associated sarcomas and use of pazopanib in bone sarcomas.

Targeting signaling pathways in osteosarcoma: Mechanisms and clinical studies

Osteosarcoma (OS) is a highly prevalent bone malignancy among adolescents, accounting for 40% of all primary malignant bone tumors. Neoadjuvant chemotherapy combined with limb-preserving surgery has effectively reduced patient disability and mortality, but pulmonary metastases and OS cells' resistance to chemotherapeutic agents are pressing challenges in the clinical management of OS. There has been an urgent need to identify new biomarkers for OS to develop specific targeted therapies. Recently, the continued advancements in genomic analysis have contributed to the identification of clinically significant molecular biomarkers for diagnosing OS, acting as therapeutic targets, and predicting prognosis. Additionally, the contemporary molecular classifications have revealed that the signaling pathways, including Wnt/β-catenin, PI3K/AKT/mTOR, JAK/STAT3, Hippo, Notch, PD-1/PD-L1, MAPK, and NF-κB, have an integral role in OS onset, progression, metastasis, and treatment response. These molecular classifications and biological markers have created new avenues for more accurate OS diagnosis and relevant treatment. We herein present a review of the recent findings for the modulatory role of signaling pathways as possible biological markers and treatment targets for OS. This review also discusses current OS therapeutic approaches, including signaling pathway-based therapies developed over the past decade. Additionally, the review covers the signaling targets involved in the curative effects of traditional Chinese medicines in the context of expression regulation of relevant genes and proteins through the signaling pathways to inhibit OS cell growth. These findings are expected to provide directions for integrating genomic, molecular, and clinical profiles to enhance OS diagnosis and treatment.

Current Status and Prospects of Targeted Therapy for Osteosarcoma

Osteosarcoma (OS) is a highly malignant tumor occurring in bone tissue with a high propensity to metastasize, and its underlying mechanisms remain largely elusive. The OS prognosis is poor, and improving the survival of OS patients remains a challenge. Current treatment methods such as surgical approaches, chemotherapeutic drugs, and immunotherapeutic drugs remain ineffective. As research progresses, targeted therapy is gradually becoming irreplaceable. In this review, several treatment modalities for osteosarcoma, such as surgery, chemotherapy, and immunotherapy, are briefly described, followed by a discussion of targeted therapy, the important targets, and new technologies for osteosarcoma treatment.

Imaging Hallmarks of Sarcoma Progression Via X-ray Computed Tomography: Beholding the Flower of Evil

Simple Summary

Sarcomas represent the largest group of rare solid tumors that arise from mesenchymal stem cells and are a leading cause of cancer death in individuals younger than 20 years of age. There is an immediate need for the development of an algorithm for the early accurate diagnosis of sarcomas due to the high rate of diagnostic inaccuracy, which reaches up to 30%. X-ray computed tomography is a non-invasive imaging technique used to obtain detailed internal images of the human or animal body in clinical practice and preclinical studies. We summarized the main imaging features of soft tissue and bone sarcomas, and noted the development of new molecular markers to reach tumor type-specific imaging. Also, we demonstrated the possibility of the use X-ray computed microtomography for non-destructive 3D visualization of sarcoma progression in preclinical studies. Finding correlations between X-ray computed tomography modalities and the results of the histopathological specimen examination may significantly increase the accuracy of diagnostics, which leads to the initiation of appropriate management in a timely manner and, consequently, to improved outcomes.

Abstract

Sarcomas are a leading cause of cancer death in individuals younger than 20 years of age and represent the largest group of rare solid tumors. To date, more than 100 morphological subtypes of sarcomas have been described, among which epidemiology, clinical features, management, and prognosis differ significantly. Delays and errors in the diagnosis of sarcomas limit the number of effective therapeutic modalities and catastrophically worsen the prognosis. Therefore, the development of an algorithm for the early accurate diagnosis of sarcomas seems to be as important as the development of novel therapeutic advances. This literature review aims to summarize the results of recent investigations regarding the imaging of sarcoma progression based on the use of X-ray computed tomography (CT) in preclinical studies and in current clinical practice through the lens of cancer hallmarks. We attempted to summarize the main CT imaging features of soft-tissue and bone sarcomas. We noted the development of new molecular markers with high specificity to antibodies and chemokines, which are expressed in particular sarcoma subtypes to reach tumor type-specific imaging. We demonstrate the possibility of the use of X-ray computed microtomography (micro-CT) for non-destructive 3D visualization of solid tumors by increasing the visibility of soft tissues with X-ray scattering agents. Based on the results of recent studies, we hypothesize that micro-CT enables the visualization of neovascularization and stroma formation in sarcomas at high-resolution in vivo and ex vivo, including the novel techniques of whole-block and whole-tissue imaging. Finding correlations between CT, PET/CT, and micro-CT imaging features, the results of the histopathological specimen examination and clinical outcomes may significantly increase the accuracy of soft-tissue and bone tumor diagnostics, which leads to the initiation of appropriate histotype-specific management in a timely manner and, consequently, to improved outcomes.

Emerging Roles and Mechanisms of lncRNA FOXD3-AS1 in Human Diseases

Numerous long noncoding RNAs (lncRNAs) have been identified as powerful regulators of human diseases. The lncRNA FOXD3-AS1 is a novel lncRNA that was recently shown to exert imperative roles in the initialization and progression of several diseases. Emerging studies have shown aberrant expression of FOXD3-AS1 and close correlation with pathophysiological traits of numerous diseases, particularly cancers. More importantly, FOXD3-AS1 was also found to ubiquitously impact a range of biological functions. This study aims to summarize the expression, associated clinicopathological features, major functions and molecular mechanisms of FOXD3-AS1 in human diseases and to explore its possible clinical applications.

Multikinase-Inhibitor Screening in Drug-resistant Osteosarcoma Patient-derived Orthotopic Xenograft Mouse Models Identifies the Clinical Potential of Regorafenib

BACKGROUND/AIM

Osteosarcoma is a recalcitrant heterogenous malignancy. The aim of the present study was to compare a series of multikinase inhibitors (MKIs) for efficacy on two drug-resistant osteosarcoma patient-derived orthotopic xenograft (PDOX) models in order to identify a clinical candidate.

MATERIALS AND METHODS

The two osteosarcoma PDOX models were tested for response to the following MKIs: pazopanib, sunitinib, sorafenib, crizotinib, and regorafenib, in comparison to first-line treatment with cisplatinum and an untreated control.

RESULTS

Regorafenib led to regression of osteosarcoma in both PDOXs. Total necrosis was observed pathologically in the regorafenib-treated tumors. Sorafenib arrested growth, without inducing regression, in one osteosarcoma model but not the other, and the other MKIs only slowed tumor growth.

CONCLUSION

The present study demonstrated that regorafenib is much more effective than the other MKIs tested and has clinical potential against recalcitrant osteosarcoma.

Advances in targeted therapy for osteosarcoma based on molecular classification

Osteosarcoma, a highly malignant tumor, is characterized by widespread and recurrent chromosomal and genetic abnormalities. In recent years, a number of elaborated sequencing analyses have made it possible to cluster the osteosarcoma based on the identification of candidate driver genes and develop targeted therapy. Here, we reviewed recent next-generation genome sequencing studies and advances in targeted therapies for osteosarcoma based on molecular classification. First, we stratified osteosarcomas into ten molecular subtypes based on genetic changes. And we analyzed potential targeted therapies for osteosarcoma based on the identified molecular subtypes. Finally, the development of targeted therapies for osteosarcoma investigated in clinical trials were further summarized and discussed. Therefore, we indicated the importance of molecular classification on the targeted therapy for osteosarcoma. And the stratification of patients based on the genetic characteristics of osteosarcoma will help to obtain a better therapeutic response to targeted therapies, bringing us closer to the era of personalized medicine.