Differential microRNA expression in canine and human osteosarcoma.

Osteosarcoma (OS) is the most common primary malignant bone tumor in dogs and humans. MicroRNAs are short non-coding RNA molecules involved in post transcriptional gene regulation controlling gene expression and playing an important role in tumor cell proliferation and dissemination. miRNAs may be useful biomarkers for OS prognosis evaluation and treatment. We compared miRNA expression in human and canine OS in order to find molecular pathways involved in the development of these neoplasms useful for therapeutic strategies. Using Real Time PCR, we detected lower expression of miR-196a, miR-1 and miR-133b in canine and human OS samples when compared with paired normal bone samples. In vitro studies on OS cells revealed that increasing the levels of miR-196a with precursor molecule, its ectopic expression induced changes in proliferation, apoptosis and migration in a variable way depending on genetic background of OS cells.