(A–C) Representative images showing the tumour size and weight in the nude mice under FTY720 treatment; scale bar = 10 mm. (D) Representative HE and IHC staining showing the changes in Ki-67 and IL-6 expression after FTY720 treatment; scale bar = 50 μm. All data are shown as the mean ± S.D. (three independent experiments). *P < 0.05; **P < 0.01; ***P < 0.001.