Basic Science and Translational Treatments

[34] Schneiderman BA, Kliethermes SA, Nystrom LM. Survival in Mesenchymal Chondrosarcoma varies based on age and tumor location: A survival analysis

Osteosarcoma – Diagnosis, Mechanisms, and Translational Developments

[42] Murphey MD, Jelinek JS, Temple HT, Flemming DJ, Gannon FH. Imaging of periosteal osteosarcoma: Radiologicpathologic comparison. Radiology.

2004;233(1):129-138

of the SEER database. Clinical Orthopaedics and Related Research.

[35] Murphey MD, Nomikos GC, Flemming DJ, Gannon FH, Temple HT, Kransdorf MJ. From the archives of AFIP. Imaging of giant cell tumor and giant cell reparative granuloma of bone: Radiologic-pathologic correlation. Radiographics. 2001;21(5):1283-1309

[36] Lim CY, Ong KO. Imaging of musculoskeletal lymphoma. Cancer Imaging. 2013;13(4):448-457

[37] Maruyama D, Watanabe T, Beppu Y, Kobayashi Y, Kim SW, Tanimoto K, et al. Primary bone lymphoma: A new and detailed characterization of 28 patients in a single-institution study. Japanese Journal of Clinical Oncology.

[38] Arceci RJ, Hann IM, Smith OP, Hoffbrand AV. Pediatric Hematology.

review of a single-center cohort. Medicine. 2016;95(21):e3625

[40] Weiss A, Khoury JD, Hoffer FA, Wu J, Billups CA, Heck RK, et al. Telangiectatic osteosarcoma: The St. Jude Children's Research Hospital's experience. Cancer. 2007;109(8):

[41] Donmez FY, Tuzun U, Basaran C, Tunaci M, Bilgic B, Acunas G. MRI findings in parosteal osteosarcoma: Correlation with histopathology.

Diagnostic and Interventional Radiology (Ankara, Turkey). 2008;14(3):142-152

[39] Gianfreda D, Musetti C, Nicastro M, Maritati F, Cobelli R, Corradi D, et al. Erdheim-Chester disease as a mimic of IgG4-related disease: A case report and a

2017;475(3):799-805

2007;37(3):216-223

Wiley; 2006

1627-1637

36

Chapter 3

Abstract

drug resistance

1. Introduction

39

Long Noncoding RNAs in

Christos Valavanis and Gabriela Stanc

osteosarcoma progression, and in therapeutic interventions.

Keywords: lncRNAs, osteosarcoma, pathogenesis, prognosis, metastasis,

Osteosarcoma is a rare malignant tumor and the most frequent primary malignant tumor of the bone affecting most often young people in childhood and adolescence [1–3]. It is of mesenchymal histogenetic origin and is characterized by the production of osteoid and fibrous stroma. It has a tendency to be highly anaplastic with cytological pleomorphism consisting of cells of epithelioid, spindle, ovoid, or giant multinucleated appearance and in most cases a mixture of them [4]. It is genetically unstable and exhibits structural chromosomal alterations [5–8]. It represents different pathological entities based on clinical, radiological, and histopathological features. Depending on histopathological features, osteosarcoma displays different subtypes, the most common among them are osteoblastic osteosarcoma, chondroblastic osteosarcoma, and fibroblastic osteosarcoma. Less frequent are telangiectatic osteosarcoma, small cell osteosarcoma, low-grade osteosarcoma, highgrade osteosarcoma, parosteal osteosarcoma, and periosteal osteosarcoma [4, 9–11].

Osteosarcoma: Mechanisms and

Long noncoding RNAs (lncRNAs) are noncoding transcripts consisting of a diverse class of long RNAs of more than 200 nucleotides in length. Recent studies have shown that lncRNAs are involved in cell signal transduction pathways, cell cycle and cell death regulation, chromatin remodeling, and gene expression regulation at the transcriptional and posttranscriptional levels. They are also involved in the metastatic process of different types of tumors, such as urothelial carcinoma, colon carcinoma, breast carcinoma, lung carcinoma, and hepatocellular carcinoma. In addition, lncRNAs demonstrate precise expression patterns in specific tissues and cells and therefore play important roles in cell differentiation and tissue development. In this chapter, we review the molecular mechanisms of lncRNA cell functions and their involvement in the pathogenesis, progression, and metastasis of osteosarcoma, a rare bone tumor of childhood and adolescence. We also review emerging clinical implications of lncRNA use as potential prognostic biomarkers and therapeutic targets, as well as their putative involvement in drug resistance, in

Potential Clinical Implications

## Chapter 3
