Origin and Therapies of Osteosarcoma.

Osteosarcoma (OS) is the most frequent primary bone tumor, mainly affecting children and young adults. Despite therapeutic advances, the 5-year survival rate is 70% but drastically decreases to 20-30% for poor responders to therapies or for patients with metastasis. No real evolution of the survival rates has been observed for four decades, explained by poor knowledge of the origin, difficulties related to diagnosis and the lack of targeted therapies for this pediatric tumor.

Molecular Chaperones in Osteosarcoma: Diagnosis and Therapeutic Issues.

Osteosarcoma (OS) is the most common form of primary bone tumor affecting mainly children and young adults. Despite therapeutic progress, the 5-year survival rate is 70%, but it drops drastically to 30% for poor responders to therapies or for patients with metastases. Identifying new therapeutic targets is thus essential.

TH1579, MTH1 inhibitor, delays tumour growth and inhibits metastases development in osteosarcoma model.

Background: Osteosarcoma (OS) is the most common primary malignant bone tumour. Unfortunately, no new treatments are approved and over the last 30 years the survival rate remains only 30% at 5 years for poor responders justifying an urgent need of new therapies. The Mutt homolog 1 (MTH1) enzyme prevents incorporation of oxidized nucleotides into DNA and recently developed MTH1 inhibitors may offer therapeutic potential as MTH1 is overexpressed in various cancers.

Analysis of mRNA, miRNA, and DNA in Bone Cells by RT-qPCR and In Situ Hybridization.

The aim of this chapter is to describe a method used to evaluate gene expression and microRNAs (miRNAs) in bone cells or tissue using Reverse transcription and quantitative Polymerase Chain Reaction (RT-qPCR), and a method to assess chromogenic in situ hybridization (CISH) on Formalin Fixed Paraffin Embedded (FFPE ) mouse bone tissue to detect both DNA and mRNA transcripts using the double digoxigenin (DIG) locked nucleic acid (LNA™) probes .

Loss of miR-198 and -206 during primary tumor progression enables metastatic dissemination in human osteosarcoma.

The metastatic dissemination is a complex multistep process by which tumor cells from a primary site enter into the systemic circulation to finally spread at distant sites. Even if this mechanism is rare at the tumor level, it remains the major cause of Osteosarcoma-patients' relapse and mortality. MicroRNAs (miRNAs) have recently been described as novel epigenetics' genes' expression regulators actively implicated in cancer progression and dissemination.