ATO prevents the transcription of GLI target genes.

<p>Human osteosarcoma cells were cultured with or without 1 µM ATO. An equivalent volume of vehicle was used as the control. Total RNA collected from osteosarcoma cell lines was examined by real-time polymerase chain reaction (PCR). A comparative Ct (ΔΔCt) analysis was performed to examine fold changes in mRNA expression compared with <i>β-actin</i>. Real-time PCR showed that ATO decreased the transcription of GLI target genes, including <i>PTCH1</i>, <i>GLI1</i>, and <i>GLI2</i>, in 143B, Saos2, HsOs1, and U2OS cells. The experiment was performed in triplicate with similar results (error bars represent mean [SD]) (*P < 0.01, **P < 0.05).</p>