Figure 1.

XB130 controls cell cycle progression and survival of WRO thyroid cancer cells. A: XB130 siRNA effectively reduced XB130 protein levels in WRO cells 48 hours after transfection. B: Down-regulation of XB130 inhibited G₁-S phase progression of WRO cells. Cells transfected with control or XB130 siRNA were stained with propidium iodide (PI) and analyzed by flow cytometry. Mean ± SEM n = 6. *P < 0.05 (compared with control siRNA). C: Reduced Ki-67 and PCNA levels in XB130 siRNA treated cells. D: Down-regulation of XB130 enhanced spontaneous and induced cell death. Cells transfected with control or XB130 siRNA were treated with staurosporine (STS, 200 nmol/L) or with Fas antibody (FasAb, clone CH11, 100 ng/ml) for 24 hours. Apoptosis was determined by flow cytometry using PI/annexin V double staining. n = 6. Mean ± SEM *P < 0.05 (compared with control siRNA).