Periostin Contributes to Cisplatin Resistance in Human Non-Small Cell Lung Cancer A549 Cells via Activation of Stat3 and Akt and Upregulation of Survivin.

BACKGROUND/AIMS Periostin is upregulated in non-small cell lung cancer (NSCLC). This study was done to explore the function of periostin in the development of cisplatin (CDDP) resistance in NSCLC. METHODS The effects of overexpression or knockdown of periostin on CDDP sensitivity was examined in A549 cells. The involvement of signal transducer and activator of transcription 3 (Stat3) and Akt signaling in the action of periostin was checked. The in vivo effect of periostin silencing on CDDP susceptibility was determined in a mouse xenograft model. RESULTS Periostin was significantly upregulated in CDDP-resistant A549 cells, compared to parental controls. Overexpression of periostin rendered A549 cells more resistant to CDDP-induced apoptosis and enhanced Stat3 and Akt phosphorylation and survivin expression. Periostin-mediated protection against CDDP-induced apoptosis was compromised by downregulation of survivin. Furthermore, knockdown of periostin re-sensitized CDDP-resistant A549 cells to CDDP. After CDDP treatment, greater volume reduction was observed in periostin-silenced xenograft tumors than in control tumors, which was accompanied by reduced levels of phosphorylated Stat3 and survivin in periostin-depleted tumors. CONCLUSION In conclusion, periostin promotes CDDP resistance in NSCLC cells largely through activation of Stat3 and Akt and upregulation of survivin and thus represents a promising target for overcoming CDDP resistance.