Knowledge atlas and emerging trends on ncRNAs of osteosarcoma: A bibliometric analysis

BACKGROUND

Osteosarcoma is a common bone sarcoma that occurs in childhood and adolescence. Although research on non-coding RNAs (ncRNAs) of osteosarcoma has been developed rapidly in recent years, a specific bibliometric analysis on this topic has not yet been performed. The bibliometric analysis aims to summarize knowledge atlas, research hotspots, and emerging trends and to provide researchers with new perspectives in further studies.

METHODS

All publications regarding ncRNAs of osteosarcoma published from 2000 to 2021 were retrieved from the Web of Science Core Collection. Quantitative indicators including the number of publications and citations, H-index, and journal citation reports were analyzed by using Excel 2019 and R software. VOSviewer and CiteSpace were used to analyze the cooperation among countries/institutions/journals/authors and the co-occurrence of keywords, keywords bursts, and references.

RESULTS

A total of 3206 publications were extracted. A significant growth trend in the annual number of publications over the past 22 years is revealed (R ² = 0.999). The most prolific country and institution were China (2260) and Shanghai Jiao Tong University (134), respectively. Professors Wang W and Liu W contributed the most to this field. The keywords were stratified into six clusters: Cluster 1 (apoptosis and growth), Cluster 2 (cancer and progression), Cluster 3 (microRNAs and downregulation), Cluster 4 (genes and differentiation), Cluster 5 (expression and biological functions), and Cluster 6 (metastasis). The long non-coding RNAs and circular RNAs have been considered as an important research hotspot in the near future.

CONCLUSION

This study offers a scientific perspective on ncRNAs of osteosarcoma and provides researchers with valuable information to understand the knowledge structure and to identify emerging trends in this field.

Targeting autophagy is a promising therapeutic strategy to overcome chemoresistance and reduce metastasis in osteosarcoma

Osteosarcoma (OS) is the most common primary bone malignancy, mainly affecting children and adolescents. Currently, surgical resection combined with adjuvant chemotherapy has been standardized for OS treatment. Despite great advances in chemotherapy for OS, its clinical prognosis remains far from satisfactory; this is due to chemoresistance, which has become a major obstacle to improving OS treatment. Autophagy, a catabolic process through which cells eliminate and recycle their own damaged proteins and organelles to provide energy, can be activated by chemotherapeutic drugs. Accumulating evidence has indicated that autophagy plays the dual role in the regulation of OS chemoresistance by either promoting drug resistance or increasing drug sensitivity. The aim of the present review was to demonstrate thatautophagy has both a cytoprotective and an autophagic cell death function in OS chemoresistance. In addition, methods to detect autophagy, autophagy inducers and inhibitors, as well as autophagy‑mediated metastasis, immunotherapy and clinical prognosis are also discussed.

Role of autophagy in osteosarcoma

Osteosarcoma (OS) is the most common primary bone tumour in children and adolescents. It is a highly aggressive tumor with a tendency to spread to the lungs, which are the most common site of metastasis. Advanced osteosarcoma patients with metastasis share a poor prognosis. Despite the use of chemotherapy to treat OS, the 5-year overall survival rate for patients has remained unchanged at 65–70% for the past 20 years. In addition, the 5-year survival of patients with a metastatic disease is around 20%, highlighting the need for novel therapeutic targets.

Autophagy is an intracellular degradation process which eliminates and recycles damaged proteins and organelles to improve cell lifespan. In the context of cancer, numerous studies have demonstrated that autophagy is used by tumor cells to repress initial steps of carcinogenesis and/or support the survival and growth of established tumors. In osteosarcoma, autophagy appears to be deregulated and could also act both as a pro or anti-tumoral process. In this manuscript, we aim to review these major findings regarding the role of autophagy in osteosarcoma.

p62/SQSTM1 - steering the cell through health and disease

SQSTM1 (also known as p62) is a multifunctional stress-inducible scaffold protein involved in diverse cellular processes. Its functions are tightly regulated through an extensive pattern of post-translational modifications, and include the isolation of cargos degraded by autophagy, induction of the antioxidant response by the Keap1-Nrf2 system, as well as the regulation of endosomal trafficking, apoptosis and inflammation. Accordingly, malfunction of SQSTM1 is associated with a wide range of diseases, including bone and muscle disorders, neurodegenerative and metabolic diseases, and multiple forms of cancer. In this Review, we summarize current knowledge regarding regulation, post-translational modifications and functions of SQSTM1, as well as how they are dysregulated in various pathogenic contexts.

Application of liquid biopsy in bone and soft tissue sarcomas: Present and future

Bone and soft tissue sarcomas account for approximately 1% of adult solid malignancies and 20% of pediatric solid malignancies. Sarcomas are divided into more than 50 subtypes. Each subtype is highly heterogeneous and characterized by significant morphological and phenotypic variability. Currently, sarcoma characterization is based on tissue biopsies. However, primary and invasive tissue biopsies may not accurately reflect the current disease condition following treatment as is may cause marked changes to the tumor cells. Liquid biopsy offers an alternative minimally invasive approach to provide dynamic tumor information, allowing for the application of precision medicine in the treatment of sarcomas. Recently, there have been numerous blood-based tumor components identified by liquid biopsy in sarcomas, including circulating tumor cells, circulating cell-free nucleic acids, tumor-derived exosomes and metabolites in circulation. Here, we summarize the current evolving technologies and then elaborate on emerging novel concepts that may further propel the field of liquid biopsy in sarcomas. We address the applications in the context of our current knowledge about liquid biopsy in sarcomas and highlight the potential of translating these recent advances into the clinic for more effective management strategies for sarcoma patients.