Inhibition of curcumin on proliferation and invasion in giant cell tumor of bone (GCTB) by targeting STAT3

Objectives: To investigate the effects of curcumin on the proliferation and invasion in cells of giant cell tumor of bone (GCTB) by targeting the signal transducer and activator transcription factor-3 (STAT3), in order to supply treatments and preventions on GCTB with new drugs and relative mechanisms. Methods: GCTB cells were collected from resection tissues of four patients with GCTB. GCTB cells were treated by curcumin. STAT3 was one of the genes influencing invasion of osteolytic tumor, so we silenced STAT3 by small interfering RNA (siRNA) and detected by Western Blot (WB). Cell counting kit-8 (CCK-8) and Transwell system were used for detecting GCTB cell proliferation and invasion. Results: Curcumin (31.5 nM) was treated on GCTB cells for 24 h. There was significant difference before (case 1, 0.685 +/- 0.026; case 2, 0.731 +/- 0.030; case 3, 0.728 +/- 0.019; case 4, 0.634 +/- 0.015) and after (case 1, 0.160 +/- 0.008; case 2, 0.769 +/- 0.014; case 3, 0.743 +/- 0.026; case 4, 0.750 +/- 0.018) curcumin treatment (P<0.01). After silencing STAT3, there was no significance before (case 1, 0.738 +/- 0.021; case 2, 0.769 +/- 0.014; case 3, 0.743 +/- 0.026; case 4, 0.750 +/- 0.018) and after (case 1, 0.704 +/- 0.010; case 2, 0.720 +/- 0.015; case 3, 0.714 +/- 0.022; case 4, 0.729 +/- 0.013) curcumin treatment. Conclusions: Curcumin inhibits the proliferation and invasion in GCTB by targeting STAT3. STAT3 might be the new therapeutic target for treating GCTB metastasis.