MiR-196a expression in human and canine osteosarcomas: A comparative study.

Osteosarcoma (OS) is the most common primary malignant bone tumour in dogs and humans. MicroRNAs are short non-coding RNA molecules involved in post-transcriptional gene expression. Here, we compared the effects of miR-196a deregulation in human and canine OS cells after having observed a more uniform distribution and stronger down-expression in the human specimens. Cell response to miR-196a transfection was different in human and canine OS. A decreased proliferation rate was seen in human MG63 and 143B OS cells, while no appreciable changes occurred in canine DAN cells. Transient decrease of motility was highly remarkable and longer in MG63, concomitant with decreased levels of annexin1, a target of miR-196a promoting cell migration and invasion. In conclusion, the effects of miR-196a over-expression on tumour cell response may be strictly related to species and cell type. Further studies are needed to define the impact of miRNA deregulation on OS development.